* xvasprintf.c: New file.

[official-gcc.git] / gcc / config / s390 / s390.c

/* Subroutines used for code generation on IBM S/390 and zSeries
   Copyright (C) 1999-2014 Free Software Foundation, Inc.
   Contributed by Hartmut Penner (hpenner@de.ibm.com) and
                  Ulrich Weigand (uweigand@de.ibm.com) and
                  Andreas Krebbel (Andreas.Krebbel@de.ibm.com).

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */

#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "rtl.h"
#include "tree.h"
#include "print-tree.h"
#include "stringpool.h"
#include "stor-layout.h"
#include "varasm.h"
#include "calls.h"
#include "tm_p.h"
#include "regs.h"
#include "hard-reg-set.h"
#include "insn-config.h"
#include "conditions.h"
#include "output.h"
#include "insn-attr.h"
#include "flags.h"
#include "except.h"
#include "hashtab.h"
#include "hash-set.h"
#include "vec.h"
#include "machmode.h"
#include "input.h"
#include "function.h"
#include "recog.h"
#include "expr.h"
#include "reload.h"
#include "diagnostic-core.h"
#include "predict.h"
#include "dominance.h"
#include "cfg.h"
#include "cfgrtl.h"
#include "cfganal.h"
#include "lcm.h"
#include "cfgbuild.h"
#include "cfgcleanup.h"
#include "basic-block.h"
#include "ggc.h"
#include "target.h"
#include "target-def.h"
#include "debug.h"
#include "langhooks.h"
#include "insn-codes.h"
#include "optabs.h"
#include "hash-table.h"
#include "tree-ssa-alias.h"
#include "internal-fn.h"
#include "gimple-fold.h"
#include "tree-eh.h"
#include "gimple-expr.h"
#include "is-a.h"
#include "gimple.h"
#include "gimplify.h"
#include "df.h"
#include "params.h"
#include "cfgloop.h"
#include "opts.h"
#include "tree-pass.h"
#include "context.h"
#include "builtins.h"
#include "rtl-iter.h"

/* Define the specific costs for a given cpu.  */

struct processor_costs
{
  /* multiplication */
  const int m;        /* cost of an M instruction.  */
  const int mghi;     /* cost of an MGHI instruction.  */
  const int mh;       /* cost of an MH instruction.  */
  const int mhi;      /* cost of an MHI instruction.  */
  const int ml;       /* cost of an ML instruction.  */
  const int mr;       /* cost of an MR instruction.  */
  const int ms;       /* cost of an MS instruction.  */
  const int msg;      /* cost of an MSG instruction.  */
  const int msgf;     /* cost of an MSGF instruction.  */
  const int msgfr;    /* cost of an MSGFR instruction.  */
  const int msgr;     /* cost of an MSGR instruction.  */
  const int msr;      /* cost of an MSR instruction.  */
  const int mult_df;  /* cost of multiplication in DFmode.  */
  const int mxbr;
  /* square root */
  const int sqxbr;    /* cost of square root in TFmode.  */
  const int sqdbr;    /* cost of square root in DFmode.  */
  const int sqebr;    /* cost of square root in SFmode.  */
  /* multiply and add */
  const int madbr;    /* cost of multiply and add in DFmode.  */
  const int maebr;    /* cost of multiply and add in SFmode.  */
  /* division */
  const int dxbr;
  const int ddbr;
  const int debr;
  const int dlgr;
  const int dlr;
  const int dr;
  const int dsgfr;
  const int dsgr;
};

const struct processor_costs *s390_cost;

static const
struct processor_costs z900_cost =
{
  COSTS_N_INSNS (5),     /* M     */
  COSTS_N_INSNS (10),    /* MGHI  */
  COSTS_N_INSNS (5),     /* MH    */
  COSTS_N_INSNS (4),     /* MHI   */
  COSTS_N_INSNS (5),     /* ML    */
  COSTS_N_INSNS (5),     /* MR    */
  COSTS_N_INSNS (4),     /* MS    */
  COSTS_N_INSNS (15),    /* MSG   */
  COSTS_N_INSNS (7),     /* MSGF  */
  COSTS_N_INSNS (7),     /* MSGFR */
  COSTS_N_INSNS (10),    /* MSGR  */
  COSTS_N_INSNS (4),     /* MSR   */
  COSTS_N_INSNS (7),     /* multiplication in DFmode */
  COSTS_N_INSNS (13),    /* MXBR */
  COSTS_N_INSNS (136),   /* SQXBR */
  COSTS_N_INSNS (44),    /* SQDBR */
  COSTS_N_INSNS (35),    /* SQEBR */
  COSTS_N_INSNS (18),    /* MADBR */
  COSTS_N_INSNS (13),    /* MAEBR */
  COSTS_N_INSNS (134),   /* DXBR */
  COSTS_N_INSNS (30),    /* DDBR */
  COSTS_N_INSNS (27),    /* DEBR */
  COSTS_N_INSNS (220),   /* DLGR */
  COSTS_N_INSNS (34),    /* DLR */
  COSTS_N_INSNS (34),    /* DR */
  COSTS_N_INSNS (32),    /* DSGFR */
  COSTS_N_INSNS (32),    /* DSGR */
};

static const
struct processor_costs z990_cost =
{
  COSTS_N_INSNS (4),     /* M     */
  COSTS_N_INSNS (2),     /* MGHI  */
  COSTS_N_INSNS (2),     /* MH    */
  COSTS_N_INSNS (2),     /* MHI   */
  COSTS_N_INSNS (4),     /* ML    */
  COSTS_N_INSNS (4),     /* MR    */
  COSTS_N_INSNS (5),     /* MS    */
  COSTS_N_INSNS (6),     /* MSG   */
  COSTS_N_INSNS (4),     /* MSGF  */
  COSTS_N_INSNS (4),     /* MSGFR */
  COSTS_N_INSNS (4),     /* MSGR  */
  COSTS_N_INSNS (4),     /* MSR   */
  COSTS_N_INSNS (1),     /* multiplication in DFmode */
  COSTS_N_INSNS (28),    /* MXBR */
  COSTS_N_INSNS (130),   /* SQXBR */
  COSTS_N_INSNS (66),    /* SQDBR */
  COSTS_N_INSNS (38),    /* SQEBR */
  COSTS_N_INSNS (1),     /* MADBR */
  COSTS_N_INSNS (1),     /* MAEBR */
  COSTS_N_INSNS (60),    /* DXBR */
  COSTS_N_INSNS (40),    /* DDBR */
  COSTS_N_INSNS (26),    /* DEBR */
  COSTS_N_INSNS (176),   /* DLGR */
  COSTS_N_INSNS (31),    /* DLR */
  COSTS_N_INSNS (31),    /* DR */
  COSTS_N_INSNS (31),    /* DSGFR */
  COSTS_N_INSNS (31),    /* DSGR */
};

static const
struct processor_costs z9_109_cost =
{
  COSTS_N_INSNS (4),     /* M     */
  COSTS_N_INSNS (2),     /* MGHI  */
  COSTS_N_INSNS (2),     /* MH    */
  COSTS_N_INSNS (2),     /* MHI   */
  COSTS_N_INSNS (4),     /* ML    */
  COSTS_N_INSNS (4),     /* MR    */
  COSTS_N_INSNS (5),     /* MS    */
  COSTS_N_INSNS (6),     /* MSG   */
  COSTS_N_INSNS (4),     /* MSGF  */
  COSTS_N_INSNS (4),     /* MSGFR */
  COSTS_N_INSNS (4),     /* MSGR  */
  COSTS_N_INSNS (4),     /* MSR   */
  COSTS_N_INSNS (1),     /* multiplication in DFmode */
  COSTS_N_INSNS (28),    /* MXBR */
  COSTS_N_INSNS (130),   /* SQXBR */
  COSTS_N_INSNS (66),    /* SQDBR */
  COSTS_N_INSNS (38),    /* SQEBR */
  COSTS_N_INSNS (1),     /* MADBR */
  COSTS_N_INSNS (1),     /* MAEBR */
  COSTS_N_INSNS (60),    /* DXBR */
  COSTS_N_INSNS (40),    /* DDBR */
  COSTS_N_INSNS (26),    /* DEBR */
  COSTS_N_INSNS (30),    /* DLGR */
  COSTS_N_INSNS (23),    /* DLR */
  COSTS_N_INSNS (23),    /* DR */
  COSTS_N_INSNS (24),    /* DSGFR */
  COSTS_N_INSNS (24),    /* DSGR */
};

static const
struct processor_costs z10_cost =
{
  COSTS_N_INSNS (10),    /* M     */
  COSTS_N_INSNS (10),    /* MGHI  */
  COSTS_N_INSNS (10),    /* MH    */
  COSTS_N_INSNS (10),    /* MHI   */
  COSTS_N_INSNS (10),    /* ML    */
  COSTS_N_INSNS (10),    /* MR    */
  COSTS_N_INSNS (10),    /* MS    */
  COSTS_N_INSNS (10),    /* MSG   */
  COSTS_N_INSNS (10),    /* MSGF  */
  COSTS_N_INSNS (10),    /* MSGFR */
  COSTS_N_INSNS (10),    /* MSGR  */
  COSTS_N_INSNS (10),    /* MSR   */
  COSTS_N_INSNS (1) ,    /* multiplication in DFmode */
  COSTS_N_INSNS (50),    /* MXBR */
  COSTS_N_INSNS (120),   /* SQXBR */
  COSTS_N_INSNS (52),    /* SQDBR */
  COSTS_N_INSNS (38),    /* SQEBR */
  COSTS_N_INSNS (1),     /* MADBR */
  COSTS_N_INSNS (1),     /* MAEBR */
  COSTS_N_INSNS (111),   /* DXBR */
  COSTS_N_INSNS (39),    /* DDBR */
  COSTS_N_INSNS (32),    /* DEBR */
  COSTS_N_INSNS (160),   /* DLGR */
  COSTS_N_INSNS (71),    /* DLR */
  COSTS_N_INSNS (71),    /* DR */
  COSTS_N_INSNS (71),    /* DSGFR */
  COSTS_N_INSNS (71),    /* DSGR */
};

static const
struct processor_costs z196_cost =
{
  COSTS_N_INSNS (7),     /* M     */
  COSTS_N_INSNS (5),     /* MGHI  */
  COSTS_N_INSNS (5),     /* MH    */
  COSTS_N_INSNS (5),     /* MHI   */
  COSTS_N_INSNS (7),     /* ML    */
  COSTS_N_INSNS (7),     /* MR    */
  COSTS_N_INSNS (6),     /* MS    */
  COSTS_N_INSNS (8),     /* MSG   */
  COSTS_N_INSNS (6),     /* MSGF  */
  COSTS_N_INSNS (6),     /* MSGFR */
  COSTS_N_INSNS (8),     /* MSGR  */
  COSTS_N_INSNS (6),     /* MSR   */
  COSTS_N_INSNS (1) ,    /* multiplication in DFmode */
  COSTS_N_INSNS (40),    /* MXBR B+40 */
  COSTS_N_INSNS (100),   /* SQXBR B+100 */
  COSTS_N_INSNS (42),    /* SQDBR B+42 */
  COSTS_N_INSNS (28),    /* SQEBR B+28 */
  COSTS_N_INSNS (1),     /* MADBR B */
  COSTS_N_INSNS (1),     /* MAEBR B */
  COSTS_N_INSNS (101),   /* DXBR B+101 */
  COSTS_N_INSNS (29),    /* DDBR */
  COSTS_N_INSNS (22),    /* DEBR */
  COSTS_N_INSNS (160),   /* DLGR cracked */
  COSTS_N_INSNS (160),   /* DLR cracked */
  COSTS_N_INSNS (160),   /* DR expanded */
  COSTS_N_INSNS (160),   /* DSGFR cracked */
  COSTS_N_INSNS (160),   /* DSGR cracked */
};

static const
struct processor_costs zEC12_cost =
{
  COSTS_N_INSNS (7),     /* M     */
  COSTS_N_INSNS (5),     /* MGHI  */
  COSTS_N_INSNS (5),     /* MH    */
  COSTS_N_INSNS (5),     /* MHI   */
  COSTS_N_INSNS (7),     /* ML    */
  COSTS_N_INSNS (7),     /* MR    */
  COSTS_N_INSNS (6),     /* MS    */
  COSTS_N_INSNS (8),     /* MSG   */
  COSTS_N_INSNS (6),     /* MSGF  */
  COSTS_N_INSNS (6),     /* MSGFR */
  COSTS_N_INSNS (8),     /* MSGR  */
  COSTS_N_INSNS (6),     /* MSR   */
  COSTS_N_INSNS (1) ,    /* multiplication in DFmode */
  COSTS_N_INSNS (40),    /* MXBR B+40 */
  COSTS_N_INSNS (100),   /* SQXBR B+100 */
  COSTS_N_INSNS (42),    /* SQDBR B+42 */
  COSTS_N_INSNS (28),    /* SQEBR B+28 */
  COSTS_N_INSNS (1),     /* MADBR B */
  COSTS_N_INSNS (1),     /* MAEBR B */
  COSTS_N_INSNS (131),   /* DXBR B+131 */
  COSTS_N_INSNS (29),    /* DDBR */
  COSTS_N_INSNS (22),    /* DEBR */
  COSTS_N_INSNS (160),   /* DLGR cracked */
  COSTS_N_INSNS (160),   /* DLR cracked */
  COSTS_N_INSNS (160),   /* DR expanded */
  COSTS_N_INSNS (160),   /* DSGFR cracked */
  COSTS_N_INSNS (160),   /* DSGR cracked */
};

extern int reload_completed;

/* Kept up to date using the SCHED_VARIABLE_ISSUE hook.  */
static rtx_insn *last_scheduled_insn;

/* Structure used to hold the components of a S/390 memory
   address.  A legitimate address on S/390 is of the general
   form
          base + index + displacement
   where any of the components is optional.

   base and index are registers of the class ADDR_REGS,
   displacement is an unsigned 12-bit immediate constant.  */

struct s390_address
{
  rtx base;
  rtx indx;
  rtx disp;
  bool pointer;
  bool literal_pool;
};

/* The following structure is embedded in the machine
   specific part of struct function.  */

struct GTY (()) s390_frame_layout
{
  /* Offset within stack frame.  */
  HOST_WIDE_INT gprs_offset;
  HOST_WIDE_INT f0_offset;
  HOST_WIDE_INT f4_offset;
  HOST_WIDE_INT f8_offset;
  HOST_WIDE_INT backchain_offset;

  /* Number of first and last gpr where slots in the register
     save area are reserved for.  */
  int first_save_gpr_slot;
  int last_save_gpr_slot;

  /* Location (FP register number) where GPRs (r0-r15) should
     be saved to.
      0 - does not need to be saved at all
     -1 - stack slot  */
  signed char gpr_save_slots[16];

  /* Number of first and last gpr to be saved, restored.  */
  int first_save_gpr;
  int first_restore_gpr;
  int last_save_gpr;
  int last_restore_gpr;

  /* Bits standing for floating point registers. Set, if the
     respective register has to be saved. Starting with reg 16 (f0)
     at the rightmost bit.
     Bit 15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
     fpr 15 13 11  9 14 12 10  8  7  5  3  1  6  4  2  0
     reg 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16  */
  unsigned int fpr_bitmap;

  /* Number of floating point registers f8-f15 which must be saved.  */
  int high_fprs;

  /* Set if return address needs to be saved.
     This flag is set by s390_return_addr_rtx if it could not use
     the initial value of r14 and therefore depends on r14 saved
     to the stack.  */
  bool save_return_addr_p;

  /* Size of stack frame.  */
  HOST_WIDE_INT frame_size;
};

/* Define the structure for the machine field in struct function.  */

struct GTY(()) machine_function
{
  struct s390_frame_layout frame_layout;

  /* Literal pool base register.  */
  rtx base_reg;

  /* True if we may need to perform branch splitting.  */
  bool split_branches_pending_p;

  bool has_landing_pad_p;

  /* True if the current function may contain a tbegin clobbering
     FPRs.  */
  bool tbegin_p;
};

/* Few accessor macros for struct cfun->machine->s390_frame_layout.  */

#define cfun_frame_layout (cfun->machine->frame_layout)
#define cfun_save_high_fprs_p (!!cfun_frame_layout.high_fprs)
#define cfun_save_arg_fprs_p (!!(TARGET_64BIT                           \
                                 ? cfun_frame_layout.fpr_bitmap & 0x0f  \
                                 : cfun_frame_layout.fpr_bitmap & 0x03))
#define cfun_gprs_save_area_size ((cfun_frame_layout.last_save_gpr_slot - \
  cfun_frame_layout.first_save_gpr_slot + 1) * UNITS_PER_LONG)
#define cfun_set_fpr_save(REGNO) (cfun->machine->frame_layout.fpr_bitmap |=    \
  (1 << (REGNO - FPR0_REGNUM)))
#define cfun_fpr_save_p(REGNO) (!!(cfun->machine->frame_layout.fpr_bitmap &    \
  (1 << (REGNO - FPR0_REGNUM))))
#define cfun_gpr_save_slot(REGNO) \
  cfun->machine->frame_layout.gpr_save_slots[REGNO]

/* Number of GPRs and FPRs used for argument passing.  */
#define GP_ARG_NUM_REG 5
#define FP_ARG_NUM_REG (TARGET_64BIT? 4 : 2)

/* A couple of shortcuts.  */
#define CONST_OK_FOR_J(x) \
        CONST_OK_FOR_CONSTRAINT_P((x), 'J', "J")
#define CONST_OK_FOR_K(x) \
        CONST_OK_FOR_CONSTRAINT_P((x), 'K', "K")
#define CONST_OK_FOR_Os(x) \
        CONST_OK_FOR_CONSTRAINT_P((x), 'O', "Os")
#define CONST_OK_FOR_Op(x) \
        CONST_OK_FOR_CONSTRAINT_P((x), 'O', "Op")
#define CONST_OK_FOR_On(x) \
        CONST_OK_FOR_CONSTRAINT_P((x), 'O', "On")

#define REGNO_PAIR_OK(REGNO, MODE)                               \
  (HARD_REGNO_NREGS ((REGNO), (MODE)) == 1 || !((REGNO) & 1))

/* That's the read ahead of the dynamic branch prediction unit in
   bytes on a z10 (or higher) CPU.  */
#define PREDICT_DISTANCE (TARGET_Z10 ? 384 : 2048)

static const int s390_hotpatch_trampoline_halfwords_default = 12;
static const int s390_hotpatch_trampoline_halfwords_max = 1000000;
static int s390_hotpatch_trampoline_halfwords = -1;

/* Return the argument of the given hotpatch attribute or the default value if
   no argument is present.  */

static inline int
get_hotpatch_attribute (tree hotpatch_attr)
{
  const_tree args;

  args = TREE_VALUE (hotpatch_attr);

  return (args) ?
    TREE_INT_CST_LOW (TREE_VALUE (args)):
    s390_hotpatch_trampoline_halfwords_default;
}

/* Check whether the hotpatch attribute is applied to a function and, if it has
   an argument, the argument is valid.  */

static tree
s390_handle_hotpatch_attribute (tree *node, tree name, tree args,
                                int flags ATTRIBUTE_UNUSED, bool *no_add_attrs)
{
  if (TREE_CODE (*node) != FUNCTION_DECL)
    {
      warning (OPT_Wattributes, "%qE attribute only applies to functions",
               name);
      *no_add_attrs = true;
    }
  else if (args)
    {
      tree expr = TREE_VALUE (args);

      if (TREE_CODE (expr) != INTEGER_CST
          || !INTEGRAL_TYPE_P (TREE_TYPE (expr))
          || wi::gtu_p (expr, s390_hotpatch_trampoline_halfwords_max))
        {
          error ("requested %qE attribute is not a non-negative integer"
                 " constant or too large (max. %d)", name,
                 s390_hotpatch_trampoline_halfwords_max);
          *no_add_attrs = true;
        }
    }

  return NULL_TREE;
}

static const struct attribute_spec s390_attribute_table[] = {
  { "hotpatch", 0, 1, true, false, false, s390_handle_hotpatch_attribute, false
  },
  /* End element.  */
  { NULL,        0, 0, false, false, false, NULL, false }
};

/* Return the alignment for LABEL.  We default to the -falign-labels
   value except for the literal pool base label.  */
int
s390_label_align (rtx label)
{
  rtx_insn *prev_insn = prev_active_insn (label);
  rtx set, src;

  if (prev_insn == NULL_RTX)
    goto old;

  set = single_set (prev_insn);

  if (set == NULL_RTX)
    goto old;

  src = SET_SRC (set);

  /* Don't align literal pool base labels.  */
  if (GET_CODE (src) == UNSPEC
      && XINT (src, 1) == UNSPEC_MAIN_BASE)
    return 0;

 old:
  return align_labels_log;
}

static machine_mode
s390_libgcc_cmp_return_mode (void)
{
  return TARGET_64BIT ? DImode : SImode;
}

static machine_mode
s390_libgcc_shift_count_mode (void)
{
  return TARGET_64BIT ? DImode : SImode;
}

static machine_mode
s390_unwind_word_mode (void)
{
  return TARGET_64BIT ? DImode : SImode;
}

/* Return true if the back end supports mode MODE.  */
static bool
s390_scalar_mode_supported_p (machine_mode mode)
{
  /* In contrast to the default implementation reject TImode constants on 31bit
     TARGET_ZARCH for ABI compliance.  */
  if (!TARGET_64BIT && TARGET_ZARCH && mode == TImode)
    return false;

  if (DECIMAL_FLOAT_MODE_P (mode))
    return default_decimal_float_supported_p ();

  return default_scalar_mode_supported_p (mode);
}

/* Set the has_landing_pad_p flag in struct machine_function to VALUE.  */

void
s390_set_has_landing_pad_p (bool value)
{
  cfun->machine->has_landing_pad_p = value;
}

/* If two condition code modes are compatible, return a condition code
   mode which is compatible with both.  Otherwise, return
   VOIDmode.  */

static machine_mode
s390_cc_modes_compatible (machine_mode m1, machine_mode m2)
{
  if (m1 == m2)
    return m1;

  switch (m1)
    {
    case CCZmode:
      if (m2 == CCUmode || m2 == CCTmode || m2 == CCZ1mode
          || m2 == CCSmode || m2 == CCSRmode || m2 == CCURmode)
        return m2;
      return VOIDmode;

    case CCSmode:
    case CCUmode:
    case CCTmode:
    case CCSRmode:
    case CCURmode:
    case CCZ1mode:
      if (m2 == CCZmode)
        return m1;

      return VOIDmode;

    default:
      return VOIDmode;
    }
  return VOIDmode;
}

/* Return true if SET either doesn't set the CC register, or else
   the source and destination have matching CC modes and that
   CC mode is at least as constrained as REQ_MODE.  */

static bool
s390_match_ccmode_set (rtx set, machine_mode req_mode)
{
  machine_mode set_mode;

  gcc_assert (GET_CODE (set) == SET);

  if (GET_CODE (SET_DEST (set)) != REG || !CC_REGNO_P (REGNO (SET_DEST (set))))
    return 1;

  set_mode = GET_MODE (SET_DEST (set));
  switch (set_mode)
    {
    case CCSmode:
    case CCSRmode:
    case CCUmode:
    case CCURmode:
    case CCLmode:
    case CCL1mode:
    case CCL2mode:
    case CCL3mode:
    case CCT1mode:
    case CCT2mode:
    case CCT3mode:
      if (req_mode != set_mode)
        return 0;
      break;

    case CCZmode:
      if (req_mode != CCSmode && req_mode != CCUmode && req_mode != CCTmode
          && req_mode != CCSRmode && req_mode != CCURmode)
        return 0;
      break;

    case CCAPmode:
    case CCANmode:
      if (req_mode != CCAmode)
        return 0;
      break;

    default:
      gcc_unreachable ();
    }

  return (GET_MODE (SET_SRC (set)) == set_mode);
}

/* Return true if every SET in INSN that sets the CC register
   has source and destination with matching CC modes and that
   CC mode is at least as constrained as REQ_MODE.
   If REQ_MODE is VOIDmode, always return false.  */

bool
s390_match_ccmode (rtx_insn *insn, machine_mode req_mode)
{
  int i;

  /* s390_tm_ccmode returns VOIDmode to indicate failure.  */
  if (req_mode == VOIDmode)
    return false;

  if (GET_CODE (PATTERN (insn)) == SET)
    return s390_match_ccmode_set (PATTERN (insn), req_mode);

  if (GET_CODE (PATTERN (insn)) == PARALLEL)
      for (i = 0; i < XVECLEN (PATTERN (insn), 0); i++)
        {
          rtx set = XVECEXP (PATTERN (insn), 0, i);
          if (GET_CODE (set) == SET)
            if (!s390_match_ccmode_set (set, req_mode))
              return false;
        }

  return true;
}

/* If a test-under-mask instruction can be used to implement
   (compare (and ... OP1) OP2), return the CC mode required
   to do that.  Otherwise, return VOIDmode.
   MIXED is true if the instruction can distinguish between
   CC1 and CC2 for mixed selected bits (TMxx), it is false
   if the instruction cannot (TM).  */

machine_mode
s390_tm_ccmode (rtx op1, rtx op2, bool mixed)
{
  int bit0, bit1;

  /* ??? Fixme: should work on CONST_DOUBLE as well.  */
  if (GET_CODE (op1) != CONST_INT || GET_CODE (op2) != CONST_INT)
    return VOIDmode;

  /* Selected bits all zero: CC0.
     e.g.: int a; if ((a & (16 + 128)) == 0) */
  if (INTVAL (op2) == 0)
    return CCTmode;

  /* Selected bits all one: CC3.
     e.g.: int a; if ((a & (16 + 128)) == 16 + 128) */
  if (INTVAL (op2) == INTVAL (op1))
    return CCT3mode;

  /* Exactly two bits selected, mixed zeroes and ones: CC1 or CC2. e.g.:
     int a;
     if ((a & (16 + 128)) == 16)         -> CCT1
     if ((a & (16 + 128)) == 128)        -> CCT2  */
  if (mixed)
    {
      bit1 = exact_log2 (INTVAL (op2));
      bit0 = exact_log2 (INTVAL (op1) ^ INTVAL (op2));
      if (bit0 != -1 && bit1 != -1)
        return bit0 > bit1 ? CCT1mode : CCT2mode;
    }

  return VOIDmode;
}

/* Given a comparison code OP (EQ, NE, etc.) and the operands
   OP0 and OP1 of a COMPARE, return the mode to be used for the
   comparison.  */

machine_mode
s390_select_ccmode (enum rtx_code code, rtx op0, rtx op1)
{
  switch (code)
    {
      case EQ:
      case NE:
        if ((GET_CODE (op0) == NEG || GET_CODE (op0) == ABS)
            && GET_MODE_CLASS (GET_MODE (op0)) == MODE_INT)
          return CCAPmode;
        if (GET_CODE (op0) == PLUS && GET_CODE (XEXP (op0, 1)) == CONST_INT
            && CONST_OK_FOR_K (INTVAL (XEXP (op0, 1))))
          return CCAPmode;
        if ((GET_CODE (op0) == PLUS || GET_CODE (op0) == MINUS
             || GET_CODE (op1) == NEG)
            && GET_MODE_CLASS (GET_MODE (op0)) == MODE_INT)
          return CCLmode;

        if (GET_CODE (op0) == AND)
          {
            /* Check whether we can potentially do it via TM.  */
            machine_mode ccmode;
            ccmode = s390_tm_ccmode (XEXP (op0, 1), op1, 1);
            if (ccmode != VOIDmode)
              {
                /* Relax CCTmode to CCZmode to allow fall-back to AND
                   if that turns out to be beneficial.  */
                return ccmode == CCTmode ? CCZmode : ccmode;
              }
          }

        if (register_operand (op0, HImode)
            && GET_CODE (op1) == CONST_INT
            && (INTVAL (op1) == -1 || INTVAL (op1) == 65535))
          return CCT3mode;
        if (register_operand (op0, QImode)
            && GET_CODE (op1) == CONST_INT
            && (INTVAL (op1) == -1 || INTVAL (op1) == 255))
          return CCT3mode;

        return CCZmode;

      case LE:
      case LT:
      case GE:
      case GT:
        /* The only overflow condition of NEG and ABS happens when
           -INT_MAX is used as parameter, which stays negative. So
           we have an overflow from a positive value to a negative.
           Using CCAP mode the resulting cc can be used for comparisons.  */
        if ((GET_CODE (op0) == NEG || GET_CODE (op0) == ABS)
            && GET_MODE_CLASS (GET_MODE (op0)) == MODE_INT)
          return CCAPmode;

        /* If constants are involved in an add instruction it is possible to use
           the resulting cc for comparisons with zero. Knowing the sign of the
           constant the overflow behavior gets predictable. e.g.:
             int a, b; if ((b = a + c) > 0)
           with c as a constant value: c < 0 -> CCAN and c >= 0 -> CCAP  */
        if (GET_CODE (op0) == PLUS && GET_CODE (XEXP (op0, 1)) == CONST_INT
            && (CONST_OK_FOR_K (INTVAL (XEXP (op0, 1)))
                || (CONST_OK_FOR_CONSTRAINT_P (INTVAL (XEXP (op0, 1)), 'O', "Os")
                    /* Avoid INT32_MIN on 32 bit.  */
                    && (!TARGET_ZARCH || INTVAL (XEXP (op0, 1)) != -0x7fffffff - 1))))
          {
            if (INTVAL (XEXP((op0), 1)) < 0)
              return CCANmode;
            else
              return CCAPmode;
          }
        /* Fall through.  */
      case UNORDERED:
      case ORDERED:
      case UNEQ:
      case UNLE:
      case UNLT:
      case UNGE:
      case UNGT:
      case LTGT:
        if ((GET_CODE (op0) == SIGN_EXTEND || GET_CODE (op0) == ZERO_EXTEND)
            && GET_CODE (op1) != CONST_INT)
          return CCSRmode;
        return CCSmode;

      case LTU:
      case GEU:
        if (GET_CODE (op0) == PLUS
            && GET_MODE_CLASS (GET_MODE (op0)) == MODE_INT)
          return CCL1mode;

        if ((GET_CODE (op0) == SIGN_EXTEND || GET_CODE (op0) == ZERO_EXTEND)
            && GET_CODE (op1) != CONST_INT)
          return CCURmode;
        return CCUmode;

      case LEU:
      case GTU:
        if (GET_CODE (op0) == MINUS
            && GET_MODE_CLASS (GET_MODE (op0)) == MODE_INT)
          return CCL2mode;

        if ((GET_CODE (op0) == SIGN_EXTEND || GET_CODE (op0) == ZERO_EXTEND)
            && GET_CODE (op1) != CONST_INT)
          return CCURmode;
        return CCUmode;

      default:
        gcc_unreachable ();
    }
}

/* Replace the comparison OP0 CODE OP1 by a semantically equivalent one
   that we can implement more efficiently.  */

static void
s390_canonicalize_comparison (int *code, rtx *op0, rtx *op1,
                              bool op0_preserve_value)
{
  if (op0_preserve_value)
    return;

  /* Convert ZERO_EXTRACT back to AND to enable TM patterns.  */
  if ((*code == EQ || *code == NE)
      && *op1 == const0_rtx
      && GET_CODE (*op0) == ZERO_EXTRACT
      && GET_CODE (XEXP (*op0, 1)) == CONST_INT
      && GET_CODE (XEXP (*op0, 2)) == CONST_INT
      && SCALAR_INT_MODE_P (GET_MODE (XEXP (*op0, 0))))
    {
      rtx inner = XEXP (*op0, 0);
      HOST_WIDE_INT modesize = GET_MODE_BITSIZE (GET_MODE (inner));
      HOST_WIDE_INT len = INTVAL (XEXP (*op0, 1));
      HOST_WIDE_INT pos = INTVAL (XEXP (*op0, 2));

      if (len > 0 && len < modesize
          && pos >= 0 && pos + len <= modesize
          && modesize <= HOST_BITS_PER_WIDE_INT)
        {
          unsigned HOST_WIDE_INT block;
          block = ((unsigned HOST_WIDE_INT) 1 << len) - 1;
          block <<= modesize - pos - len;

          *op0 = gen_rtx_AND (GET_MODE (inner), inner,
                              gen_int_mode (block, GET_MODE (inner)));
        }
    }

  /* Narrow AND of memory against immediate to enable TM.  */
  if ((*code == EQ || *code == NE)
      && *op1 == const0_rtx
      && GET_CODE (*op0) == AND
      && GET_CODE (XEXP (*op0, 1)) == CONST_INT
      && SCALAR_INT_MODE_P (GET_MODE (XEXP (*op0, 0))))
    {
      rtx inner = XEXP (*op0, 0);
      rtx mask = XEXP (*op0, 1);

      /* Ignore paradoxical SUBREGs if all extra bits are masked out.  */
      if (GET_CODE (inner) == SUBREG
          && SCALAR_INT_MODE_P (GET_MODE (SUBREG_REG (inner)))
          && (GET_MODE_SIZE (GET_MODE (inner))
              >= GET_MODE_SIZE (GET_MODE (SUBREG_REG (inner))))
          && ((INTVAL (mask)
               & GET_MODE_MASK (GET_MODE (inner))
               & ~GET_MODE_MASK (GET_MODE (SUBREG_REG (inner))))
              == 0))
        inner = SUBREG_REG (inner);

      /* Do not change volatile MEMs.  */
      if (MEM_P (inner) && !MEM_VOLATILE_P (inner))
        {
          int part = s390_single_part (XEXP (*op0, 1),
                                       GET_MODE (inner), QImode, 0);
          if (part >= 0)
            {
              mask = gen_int_mode (s390_extract_part (mask, QImode, 0), QImode);
              inner = adjust_address_nv (inner, QImode, part);
              *op0 = gen_rtx_AND (QImode, inner, mask);
            }
        }
    }

  /* Narrow comparisons against 0xffff to HImode if possible.  */
  if ((*code == EQ || *code == NE)
      && GET_CODE (*op1) == CONST_INT
      && INTVAL (*op1) == 0xffff
      && SCALAR_INT_MODE_P (GET_MODE (*op0))
      && (nonzero_bits (*op0, GET_MODE (*op0))
          & ~(unsigned HOST_WIDE_INT) 0xffff) == 0)
    {
      *op0 = gen_lowpart (HImode, *op0);
      *op1 = constm1_rtx;
    }

  /* Remove redundant UNSPEC_STRCMPCC_TO_INT conversions if possible.  */
  if (GET_CODE (*op0) == UNSPEC
      && XINT (*op0, 1) == UNSPEC_STRCMPCC_TO_INT
      && XVECLEN (*op0, 0) == 1
      && GET_MODE (XVECEXP (*op0, 0, 0)) == CCUmode
      && GET_CODE (XVECEXP (*op0, 0, 0)) == REG
      && REGNO (XVECEXP (*op0, 0, 0)) == CC_REGNUM
      && *op1 == const0_rtx)
    {
      enum rtx_code new_code = UNKNOWN;
      switch (*code)
        {
          case EQ: new_code = EQ;  break;
          case NE: new_code = NE;  break;
          case LT: new_code = GTU; break;
          case GT: new_code = LTU; break;
          case LE: new_code = GEU; break;
          case GE: new_code = LEU; break;
          default: break;
        }

      if (new_code != UNKNOWN)
        {
          *op0 = XVECEXP (*op0, 0, 0);
          *code = new_code;
        }
    }

  /* Remove redundant UNSPEC_CC_TO_INT conversions if possible.  */
  if (GET_CODE (*op0) == UNSPEC
      && XINT (*op0, 1) == UNSPEC_CC_TO_INT
      && XVECLEN (*op0, 0) == 1
      && GET_CODE (XVECEXP (*op0, 0, 0)) == REG
      && REGNO (XVECEXP (*op0, 0, 0)) == CC_REGNUM
      && CONST_INT_P (*op1))
    {
      enum rtx_code new_code = UNKNOWN;
      switch (GET_MODE (XVECEXP (*op0, 0, 0)))
        {
        case CCZmode:
        case CCRAWmode:
          switch (*code)
            {
            case EQ: new_code = EQ;  break;
            case NE: new_code = NE;  break;
            default: break;
            }
          break;
        default: break;
        }

      if (new_code != UNKNOWN)
        {
          /* For CCRAWmode put the required cc mask into the second
             operand.  */
        if (GET_MODE (XVECEXP (*op0, 0, 0)) == CCRAWmode
            && INTVAL (*op1) >= 0 && INTVAL (*op1) <= 3)
            *op1 = gen_rtx_CONST_INT (VOIDmode, 1 << (3 - INTVAL (*op1)));
          *op0 = XVECEXP (*op0, 0, 0);
          *code = new_code;
        }
    }

  /* Simplify cascaded EQ, NE with const0_rtx.  */
  if ((*code == NE || *code == EQ)
      && (GET_CODE (*op0) == EQ || GET_CODE (*op0) == NE)
      && GET_MODE (*op0) == SImode
      && GET_MODE (XEXP (*op0, 0)) == CCZ1mode
      && REG_P (XEXP (*op0, 0))
      && XEXP (*op0, 1) == const0_rtx
      && *op1 == const0_rtx)
    {
      if ((*code == EQ && GET_CODE (*op0) == NE)
          || (*code == NE && GET_CODE (*op0) == EQ))
        *code = EQ;
      else
        *code = NE;
      *op0 = XEXP (*op0, 0);
    }

  /* Prefer register over memory as first operand.  */
  if (MEM_P (*op0) && REG_P (*op1))
    {
      rtx tem = *op0; *op0 = *op1; *op1 = tem;
      *code = (int)swap_condition ((enum rtx_code)*code);
    }
}

/* Emit a compare instruction suitable to implement the comparison
   OP0 CODE OP1.  Return the correct condition RTL to be placed in
   the IF_THEN_ELSE of the conditional branch testing the result.  */

rtx
s390_emit_compare (enum rtx_code code, rtx op0, rtx op1)
{
  machine_mode mode = s390_select_ccmode (code, op0, op1);
  rtx cc;

  /* Do not output a redundant compare instruction if a compare_and_swap
     pattern already computed the result and the machine modes are compatible.  */
  if (GET_MODE_CLASS (GET_MODE (op0)) == MODE_CC)
    {
      gcc_assert (s390_cc_modes_compatible (GET_MODE (op0), mode)
                  == GET_MODE (op0));
      cc = op0;
    }
  else
    {
      cc = gen_rtx_REG (mode, CC_REGNUM);
      emit_insn (gen_rtx_SET (VOIDmode, cc, gen_rtx_COMPARE (mode, op0, op1)));
    }

  return gen_rtx_fmt_ee (code, VOIDmode, cc, const0_rtx);
}

/* Emit a SImode compare and swap instruction setting MEM to NEW_RTX if OLD
   matches CMP.
   Return the correct condition RTL to be placed in the IF_THEN_ELSE of the
   conditional branch testing the result.  */

static rtx
s390_emit_compare_and_swap (enum rtx_code code, rtx old, rtx mem,
                            rtx cmp, rtx new_rtx)
{
  emit_insn (gen_atomic_compare_and_swapsi_internal (old, mem, cmp, new_rtx));
  return s390_emit_compare (code, gen_rtx_REG (CCZ1mode, CC_REGNUM),
                            const0_rtx);
}

/* Emit a jump instruction to TARGET and return it.  If COND is
   NULL_RTX, emit an unconditional jump, else a conditional jump under
   condition COND.  */

rtx_insn *
s390_emit_jump (rtx target, rtx cond)
{
  rtx insn;

  target = gen_rtx_LABEL_REF (VOIDmode, target);
  if (cond)
    target = gen_rtx_IF_THEN_ELSE (VOIDmode, cond, target, pc_rtx);

  insn = gen_rtx_SET (VOIDmode, pc_rtx, target);
  return emit_jump_insn (insn);
}

/* Return branch condition mask to implement a branch
   specified by CODE.  Return -1 for invalid comparisons.  */

int
s390_branch_condition_mask (rtx code)
{
  const int CC0 = 1 << 3;
  const int CC1 = 1 << 2;
  const int CC2 = 1 << 1;
  const int CC3 = 1 << 0;

  gcc_assert (GET_CODE (XEXP (code, 0)) == REG);
  gcc_assert (REGNO (XEXP (code, 0)) == CC_REGNUM);
  gcc_assert (XEXP (code, 1) == const0_rtx
              || (GET_MODE (XEXP (code, 0)) == CCRAWmode
                  && CONST_INT_P (XEXP (code, 1))));


  switch (GET_MODE (XEXP (code, 0)))
    {
    case CCZmode:
    case CCZ1mode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC0;
        case NE:        return CC1 | CC2 | CC3;
        default:        return -1;
        }
      break;

    case CCT1mode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC1;
        case NE:        return CC0 | CC2 | CC3;
        default:        return -1;
        }
      break;

    case CCT2mode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC2;
        case NE:        return CC0 | CC1 | CC3;
        default:        return -1;
        }
      break;

    case CCT3mode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC3;
        case NE:        return CC0 | CC1 | CC2;
        default:        return -1;
        }
      break;

    case CCLmode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC0 | CC2;
        case NE:        return CC1 | CC3;
        default:        return -1;
        }
      break;

    case CCL1mode:
      switch (GET_CODE (code))
        {
        case LTU:       return CC2 | CC3;  /* carry */
        case GEU:       return CC0 | CC1;  /* no carry */
        default:        return -1;
        }
      break;

    case CCL2mode:
      switch (GET_CODE (code))
        {
        case GTU:       return CC0 | CC1;  /* borrow */
        case LEU:       return CC2 | CC3;  /* no borrow */
        default:        return -1;
        }
      break;

    case CCL3mode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC0 | CC2;
        case NE:        return CC1 | CC3;
        case LTU:       return CC1;
        case GTU:       return CC3;
        case LEU:       return CC1 | CC2;
        case GEU:       return CC2 | CC3;
        default:        return -1;
        }

    case CCUmode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC0;
        case NE:        return CC1 | CC2 | CC3;
        case LTU:       return CC1;
        case GTU:       return CC2;
        case LEU:       return CC0 | CC1;
        case GEU:       return CC0 | CC2;
        default:        return -1;
        }
      break;

    case CCURmode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC0;
        case NE:        return CC2 | CC1 | CC3;
        case LTU:       return CC2;
        case GTU:       return CC1;
        case LEU:       return CC0 | CC2;
        case GEU:       return CC0 | CC1;
        default:        return -1;
        }
      break;

    case CCAPmode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC0;
        case NE:        return CC1 | CC2 | CC3;
        case LT:        return CC1 | CC3;
        case GT:        return CC2;
        case LE:        return CC0 | CC1 | CC3;
        case GE:        return CC0 | CC2;
        default:        return -1;
        }
      break;

    case CCANmode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC0;
        case NE:        return CC1 | CC2 | CC3;
        case LT:        return CC1;
        case GT:        return CC2 | CC3;
        case LE:        return CC0 | CC1;
        case GE:        return CC0 | CC2 | CC3;
        default:        return -1;
        }
      break;

    case CCSmode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC0;
        case NE:        return CC1 | CC2 | CC3;
        case LT:        return CC1;
        case GT:        return CC2;
        case LE:        return CC0 | CC1;
        case GE:        return CC0 | CC2;
        case UNORDERED: return CC3;
        case ORDERED:   return CC0 | CC1 | CC2;
        case UNEQ:      return CC0 | CC3;
        case UNLT:      return CC1 | CC3;
        case UNGT:      return CC2 | CC3;
        case UNLE:      return CC0 | CC1 | CC3;
        case UNGE:      return CC0 | CC2 | CC3;
        case LTGT:      return CC1 | CC2;
        default:        return -1;
        }
      break;

    case CCSRmode:
      switch (GET_CODE (code))
        {
        case EQ:        return CC0;
        case NE:        return CC2 | CC1 | CC3;
        case LT:        return CC2;
        case GT:        return CC1;
        case LE:        return CC0 | CC2;
        case GE:        return CC0 | CC1;
        case UNORDERED: return CC3;
        case ORDERED:   return CC0 | CC2 | CC1;
        case UNEQ:      return CC0 | CC3;
        case UNLT:      return CC2 | CC3;
        case UNGT:      return CC1 | CC3;
        case UNLE:      return CC0 | CC2 | CC3;
        case UNGE:      return CC0 | CC1 | CC3;
        case LTGT:      return CC2 | CC1;
        default:        return -1;
        }
      break;

    case CCRAWmode:
      switch (GET_CODE (code))
        {
        case EQ:
          return INTVAL (XEXP (code, 1));
        case NE:
          return (INTVAL (XEXP (code, 1))) ^ 0xf;
        default:
          gcc_unreachable ();
        }

    default:
      return -1;
    }
}


/* Return branch condition mask to implement a compare and branch
   specified by CODE.  Return -1 for invalid comparisons.  */

int
s390_compare_and_branch_condition_mask (rtx code)
{
  const int CC0 = 1 << 3;
  const int CC1 = 1 << 2;
  const int CC2 = 1 << 1;

  switch (GET_CODE (code))
    {
    case EQ:
      return CC0;
    case NE:
      return CC1 | CC2;
    case LT:
    case LTU:
      return CC1;
    case GT:
    case GTU:
      return CC2;
    case LE:
    case LEU:
      return CC0 | CC1;
    case GE:
    case GEU:
      return CC0 | CC2;
    default:
      gcc_unreachable ();
    }
  return -1;
}

/* If INV is false, return assembler mnemonic string to implement
   a branch specified by CODE.  If INV is true, return mnemonic
   for the corresponding inverted branch.  */

static const char *
s390_branch_condition_mnemonic (rtx code, int inv)
{
  int mask;

  static const char *const mnemonic[16] =
    {
      NULL, "o", "h", "nle",
      "l", "nhe", "lh", "ne",
      "e", "nlh", "he", "nl",
      "le", "nh", "no", NULL
    };

  if (GET_CODE (XEXP (code, 0)) == REG
      && REGNO (XEXP (code, 0)) == CC_REGNUM
      && (XEXP (code, 1) == const0_rtx
          || (GET_MODE (XEXP (code, 0)) == CCRAWmode
              && CONST_INT_P (XEXP (code, 1)))))
    mask = s390_branch_condition_mask (code);
  else
    mask = s390_compare_and_branch_condition_mask (code);

  gcc_assert (mask >= 0);

  if (inv)
    mask ^= 15;

  gcc_assert (mask >= 1 && mask <= 14);

  return mnemonic[mask];
}

/* Return the part of op which has a value different from def.
   The size of the part is determined by mode.
   Use this function only if you already know that op really
   contains such a part.  */

unsigned HOST_WIDE_INT
s390_extract_part (rtx op, machine_mode mode, int def)
{
  unsigned HOST_WIDE_INT value = 0;
  int max_parts = HOST_BITS_PER_WIDE_INT / GET_MODE_BITSIZE (mode);
  int part_bits = GET_MODE_BITSIZE (mode);
  unsigned HOST_WIDE_INT part_mask
    = ((unsigned HOST_WIDE_INT)1 << part_bits) - 1;
  int i;

  for (i = 0; i < max_parts; i++)
    {
      if (i == 0)
        value = (unsigned HOST_WIDE_INT) INTVAL (op);
      else
        value >>= part_bits;

      if ((value & part_mask) != (def & part_mask))
        return value & part_mask;
    }

  gcc_unreachable ();
}

/* If OP is an integer constant of mode MODE with exactly one
   part of mode PART_MODE unequal to DEF, return the number of that
   part. Otherwise, return -1.  */

int
s390_single_part (rtx op,
                  machine_mode mode,
                  machine_mode part_mode,
                  int def)
{
  unsigned HOST_WIDE_INT value = 0;
  int n_parts = GET_MODE_SIZE (mode) / GET_MODE_SIZE (part_mode);
  unsigned HOST_WIDE_INT part_mask
    = ((unsigned HOST_WIDE_INT)1 << GET_MODE_BITSIZE (part_mode)) - 1;
  int i, part = -1;

  if (GET_CODE (op) != CONST_INT)
    return -1;

  for (i = 0; i < n_parts; i++)
    {
      if (i == 0)
        value = (unsigned HOST_WIDE_INT) INTVAL (op);
      else
        value >>= GET_MODE_BITSIZE (part_mode);

      if ((value & part_mask) != (def & part_mask))
        {
          if (part != -1)
            return -1;
          else
            part = i;
        }
    }
  return part == -1 ? -1 : n_parts - 1 - part;
}

/* Return true if IN contains a contiguous bitfield in the lower SIZE
   bits and no other bits are set in IN.  POS and LENGTH can be used
   to obtain the start position and the length of the bitfield.

   POS gives the position of the first bit of the bitfield counting
   from the lowest order bit starting with zero.  In order to use this
   value for S/390 instructions this has to be converted to "bits big
   endian" style.  */

bool
s390_contiguous_bitmask_p (unsigned HOST_WIDE_INT in, int size,
                           int *pos, int *length)
{
  int tmp_pos = 0;
  int tmp_length = 0;
  int i;
  unsigned HOST_WIDE_INT mask = 1ULL;
  bool contiguous = false;

  for (i = 0; i < size; mask <<= 1, i++)
    {
      if (contiguous)
        {
          if (mask & in)
            tmp_length++;
          else
            break;
        }
      else
        {
          if (mask & in)
            {
              contiguous = true;
              tmp_length++;
            }
          else
            tmp_pos++;
        }
    }

  if (!tmp_length)
    return false;

  /* Calculate a mask for all bits beyond the contiguous bits.  */
  mask = (-1LL & ~(((1ULL << (tmp_length + tmp_pos - 1)) << 1) - 1));

  if (mask & in)
    return false;

  if (tmp_length + tmp_pos - 1 > size)
    return false;

  if (length)
    *length = tmp_length;

  if (pos)
    *pos = tmp_pos;

  return true;
}

/* Check whether a rotate of ROTL followed by an AND of CONTIG is
   equivalent to a shift followed by the AND.  In particular, CONTIG
   should not overlap the (rotated) bit 0/bit 63 gap.  Negative values
   for ROTL indicate a rotate to the right.  */

bool
s390_extzv_shift_ok (int bitsize, int rotl, unsigned HOST_WIDE_INT contig)
{
  int pos, len;
  bool ok;

  ok = s390_contiguous_bitmask_p (contig, bitsize, &pos, &len);
  gcc_assert (ok);

  return ((rotl >= 0 && rotl <= pos)
          || (rotl < 0 && -rotl <= bitsize - len - pos));
}

/* Check whether we can (and want to) split a double-word
   move in mode MODE from SRC to DST into two single-word
   moves, moving the subword FIRST_SUBWORD first.  */

bool
s390_split_ok_p (rtx dst, rtx src, machine_mode mode, int first_subword)
{
  /* Floating point registers cannot be split.  */
  if (FP_REG_P (src) || FP_REG_P (dst))
    return false;

  /* We don't need to split if operands are directly accessible.  */
  if (s_operand (src, mode) || s_operand (dst, mode))
    return false;

  /* Non-offsettable memory references cannot be split.  */
  if ((GET_CODE (src) == MEM && !offsettable_memref_p (src))
      || (GET_CODE (dst) == MEM && !offsettable_memref_p (dst)))
    return false;

  /* Moving the first subword must not clobber a register
     needed to move the second subword.  */
  if (register_operand (dst, mode))
    {
      rtx subreg = operand_subword (dst, first_subword, 0, mode);
      if (reg_overlap_mentioned_p (subreg, src))
        return false;
    }

  return true;
}

/* Return true if it can be proven that [MEM1, MEM1 + SIZE]
   and [MEM2, MEM2 + SIZE] do overlap and false
   otherwise.  */

bool
s390_overlap_p (rtx mem1, rtx mem2, HOST_WIDE_INT size)
{
  rtx addr1, addr2, addr_delta;
  HOST_WIDE_INT delta;

  if (GET_CODE (mem1) != MEM || GET_CODE (mem2) != MEM)
    return true;

  if (size == 0)
    return false;

  addr1 = XEXP (mem1, 0);
  addr2 = XEXP (mem2, 0);

  addr_delta = simplify_binary_operation (MINUS, Pmode, addr2, addr1);

  /* This overlapping check is used by peepholes merging memory block operations.
     Overlapping operations would otherwise be recognized by the S/390 hardware
     and would fall back to a slower implementation. Allowing overlapping
     operations would lead to slow code but not to wrong code. Therefore we are
     somewhat optimistic if we cannot prove that the memory blocks are
     overlapping.
     That's why we return false here although this may accept operations on
     overlapping memory areas.  */
  if (!addr_delta || GET_CODE (addr_delta) != CONST_INT)
    return false;

  delta = INTVAL (addr_delta);

  if (delta == 0
      || (delta > 0 && delta < size)
      || (delta < 0 && -delta < size))
    return true;

  return false;
}

/* Check whether the address of memory reference MEM2 equals exactly
   the address of memory reference MEM1 plus DELTA.  Return true if
   we can prove this to be the case, false otherwise.  */

bool
s390_offset_p (rtx mem1, rtx mem2, rtx delta)
{
  rtx addr1, addr2, addr_delta;

  if (GET_CODE (mem1) != MEM || GET_CODE (mem2) != MEM)
    return false;

  addr1 = XEXP (mem1, 0);
  addr2 = XEXP (mem2, 0);

  addr_delta = simplify_binary_operation (MINUS, Pmode, addr2, addr1);
  if (!addr_delta || !rtx_equal_p (addr_delta, delta))
    return false;

  return true;
}

/* Expand logical operator CODE in mode MODE with operands OPERANDS.  */

void
s390_expand_logical_operator (enum rtx_code code, machine_mode mode,
                              rtx *operands)
{
  machine_mode wmode = mode;
  rtx dst = operands[0];
  rtx src1 = operands[1];
  rtx src2 = operands[2];
  rtx op, clob, tem;

  /* If we cannot handle the operation directly, use a temp register.  */
  if (!s390_logical_operator_ok_p (operands))
    dst = gen_reg_rtx (mode);

  /* QImode and HImode patterns make sense only if we have a destination
     in memory.  Otherwise perform the operation in SImode.  */
  if ((mode == QImode || mode == HImode) && GET_CODE (dst) != MEM)
    wmode = SImode;

  /* Widen operands if required.  */
  if (mode != wmode)
    {
      if (GET_CODE (dst) == SUBREG
          && (tem = simplify_subreg (wmode, dst, mode, 0)) != 0)
        dst = tem;
      else if (REG_P (dst))
        dst = gen_rtx_SUBREG (wmode, dst, 0);
      else
        dst = gen_reg_rtx (wmode);

      if (GET_CODE (src1) == SUBREG
          && (tem = simplify_subreg (wmode, src1, mode, 0)) != 0)
        src1 = tem;
      else if (GET_MODE (src1) != VOIDmode)
        src1 = gen_rtx_SUBREG (wmode, force_reg (mode, src1), 0);

      if (GET_CODE (src2) == SUBREG
          && (tem = simplify_subreg (wmode, src2, mode, 0)) != 0)
        src2 = tem;
      else if (GET_MODE (src2) != VOIDmode)
        src2 = gen_rtx_SUBREG (wmode, force_reg (mode, src2), 0);
    }

  /* Emit the instruction.  */
  op = gen_rtx_SET (VOIDmode, dst, gen_rtx_fmt_ee (code, wmode, src1, src2));
  clob = gen_rtx_CLOBBER (VOIDmode, gen_rtx_REG (CCmode, CC_REGNUM));
  emit_insn (gen_rtx_PARALLEL (VOIDmode, gen_rtvec (2, op, clob)));

  /* Fix up the destination if needed.  */
  if (dst != operands[0])
    emit_move_insn (operands[0], gen_lowpart (mode, dst));
}

/* Check whether OPERANDS are OK for a logical operation (AND, IOR, XOR).  */

bool
s390_logical_operator_ok_p (rtx *operands)
{
  /* If the destination operand is in memory, it needs to coincide
     with one of the source operands.  After reload, it has to be
     the first source operand.  */
  if (GET_CODE (operands[0]) == MEM)
    return rtx_equal_p (operands[0], operands[1])
           || (!reload_completed && rtx_equal_p (operands[0], operands[2]));

  return true;
}

/* Narrow logical operation CODE of memory operand MEMOP with immediate
   operand IMMOP to switch from SS to SI type instructions.  */

void
s390_narrow_logical_operator (enum rtx_code code, rtx *memop, rtx *immop)
{
  int def = code == AND ? -1 : 0;
  HOST_WIDE_INT mask;
  int part;

  gcc_assert (GET_CODE (*memop) == MEM);
  gcc_assert (!MEM_VOLATILE_P (*memop));

  mask = s390_extract_part (*immop, QImode, def);
  part = s390_single_part (*immop, GET_MODE (*memop), QImode, def);
  gcc_assert (part >= 0);

  *memop = adjust_address (*memop, QImode, part);
  *immop = gen_int_mode (mask, QImode);
}


/* How to allocate a 'struct machine_function'.  */

static struct machine_function *
s390_init_machine_status (void)
{
  return ggc_cleared_alloc<machine_function> ();
}

/* Map for smallest class containing reg regno.  */

const enum reg_class regclass_map[FIRST_PSEUDO_REGISTER] =
{ GENERAL_REGS, ADDR_REGS, ADDR_REGS, ADDR_REGS,
  ADDR_REGS,    ADDR_REGS, ADDR_REGS, ADDR_REGS,
  ADDR_REGS,    ADDR_REGS, ADDR_REGS, ADDR_REGS,
  ADDR_REGS,    ADDR_REGS, ADDR_REGS, ADDR_REGS,
  FP_REGS,      FP_REGS,   FP_REGS,   FP_REGS,
  FP_REGS,      FP_REGS,   FP_REGS,   FP_REGS,
  FP_REGS,      FP_REGS,   FP_REGS,   FP_REGS,
  FP_REGS,      FP_REGS,   FP_REGS,   FP_REGS,
  ADDR_REGS,    CC_REGS,   ADDR_REGS, ADDR_REGS,
  ACCESS_REGS,  ACCESS_REGS
};

/* Return attribute type of insn.  */

static enum attr_type
s390_safe_attr_type (rtx_insn *insn)
{
  if (recog_memoized (insn) >= 0)
    return get_attr_type (insn);
  else
    return TYPE_NONE;
}

/* Return true if DISP is a valid short displacement.  */

static bool
s390_short_displacement (rtx disp)
{
  /* No displacement is OK.  */
  if (!disp)
    return true;

  /* Without the long displacement facility we don't need to
     distingiush between long and short displacement.  */
  if (!TARGET_LONG_DISPLACEMENT)
    return true;

  /* Integer displacement in range.  */
  if (GET_CODE (disp) == CONST_INT)
    return INTVAL (disp) >= 0 && INTVAL (disp) < 4096;

  /* GOT offset is not OK, the GOT can be large.  */
  if (GET_CODE (disp) == CONST
      && GET_CODE (XEXP (disp, 0)) == UNSPEC
      && (XINT (XEXP (disp, 0), 1) == UNSPEC_GOT
          || XINT (XEXP (disp, 0), 1) == UNSPEC_GOTNTPOFF))
    return false;

  /* All other symbolic constants are literal pool references,
     which are OK as the literal pool must be small.  */
  if (GET_CODE (disp) == CONST)
    return true;

  return false;
}

/* Decompose a RTL expression ADDR for a memory address into
   its components, returned in OUT.

   Returns false if ADDR is not a valid memory address, true
   otherwise.  If OUT is NULL, don't return the components,
   but check for validity only.

   Note: Only addresses in canonical form are recognized.
   LEGITIMIZE_ADDRESS should convert non-canonical forms to the
   canonical form so that they will be recognized.  */

static int
s390_decompose_address (rtx addr, struct s390_address *out)
{
  HOST_WIDE_INT offset = 0;
  rtx base = NULL_RTX;
  rtx indx = NULL_RTX;
  rtx disp = NULL_RTX;
  rtx orig_disp;
  bool pointer = false;
  bool base_ptr = false;
  bool indx_ptr = false;
  bool literal_pool = false;

  /* We may need to substitute the literal pool base register into the address
     below.  However, at this point we do not know which register is going to
     be used as base, so we substitute the arg pointer register.  This is going
     to be treated as holding a pointer below -- it shouldn't be used for any
     other purpose.  */
  rtx fake_pool_base = gen_rtx_REG (Pmode, ARG_POINTER_REGNUM);

  /* Decompose address into base + index + displacement.  */

  if (GET_CODE (addr) == REG || GET_CODE (addr) == UNSPEC)
    base = addr;

  else if (GET_CODE (addr) == PLUS)
    {
      rtx op0 = XEXP (addr, 0);
      rtx op1 = XEXP (addr, 1);
      enum rtx_code code0 = GET_CODE (op0);
      enum rtx_code code1 = GET_CODE (op1);

      if (code0 == REG || code0 == UNSPEC)
        {
          if (code1 == REG || code1 == UNSPEC)
            {
              indx = op0;       /* index + base */
              base = op1;
            }

          else
            {
              base = op0;       /* base + displacement */
              disp = op1;
            }
        }

      else if (code0 == PLUS)
        {
          indx = XEXP (op0, 0); /* index + base + disp */
          base = XEXP (op0, 1);
          disp = op1;
        }

      else
        {
          return false;
        }
    }

  else
    disp = addr;                /* displacement */

  /* Extract integer part of displacement.  */
  orig_disp = disp;
  if (disp)
    {
      if (GET_CODE (disp) == CONST_INT)
        {
          offset = INTVAL (disp);
          disp = NULL_RTX;
        }
      else if (GET_CODE (disp) == CONST
               && GET_CODE (XEXP (disp, 0)) == PLUS
               && GET_CODE (XEXP (XEXP (disp, 0), 1)) == CONST_INT)
        {
          offset = INTVAL (XEXP (XEXP (disp, 0), 1));
          disp = XEXP (XEXP (disp, 0), 0);
        }
    }

  /* Strip off CONST here to avoid special case tests later.  */
  if (disp && GET_CODE (disp) == CONST)
    disp = XEXP (disp, 0);

  /* We can convert literal pool addresses to
     displacements by basing them off the base register.  */
  if (disp && GET_CODE (disp) == SYMBOL_REF && CONSTANT_POOL_ADDRESS_P (disp))
    {
      /* Either base or index must be free to hold the base register.  */
      if (!base)
        base = fake_pool_base, literal_pool = true;
      else if (!indx)
        indx = fake_pool_base, literal_pool = true;
      else
        return false;

      /* Mark up the displacement.  */
      disp = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, disp),
                             UNSPEC_LTREL_OFFSET);
    }

  /* Validate base register.  */
  if (base)
    {
      if (GET_CODE (base) == UNSPEC)
        switch (XINT (base, 1))
          {
          case UNSPEC_LTREF:
            if (!disp)
              disp = gen_rtx_UNSPEC (Pmode,
                                     gen_rtvec (1, XVECEXP (base, 0, 0)),
                                     UNSPEC_LTREL_OFFSET);
            else
              return false;

            base = XVECEXP (base, 0, 1);
            break;

          case UNSPEC_LTREL_BASE:
            if (XVECLEN (base, 0) == 1)
              base = fake_pool_base, literal_pool = true;
            else
              base = XVECEXP (base, 0, 1);
            break;

          default:
            return false;
          }

      if (!REG_P (base)
          || (GET_MODE (base) != SImode
              && GET_MODE (base) != Pmode))
        return false;

      if (REGNO (base) == STACK_POINTER_REGNUM
          || REGNO (base) == FRAME_POINTER_REGNUM
          || ((reload_completed || reload_in_progress)
              && frame_pointer_needed
              && REGNO (base) == HARD_FRAME_POINTER_REGNUM)
          || REGNO (base) == ARG_POINTER_REGNUM
          || (flag_pic
              && REGNO (base) == PIC_OFFSET_TABLE_REGNUM))
        pointer = base_ptr = true;

      if ((reload_completed || reload_in_progress)
          && base == cfun->machine->base_reg)
        pointer = base_ptr = literal_pool = true;
    }

  /* Validate index register.  */
  if (indx)
    {
      if (GET_CODE (indx) == UNSPEC)
        switch (XINT (indx, 1))
          {
          case UNSPEC_LTREF:
            if (!disp)
              disp = gen_rtx_UNSPEC (Pmode,
                                     gen_rtvec (1, XVECEXP (indx, 0, 0)),
                                     UNSPEC_LTREL_OFFSET);
            else
              return false;

            indx = XVECEXP (indx, 0, 1);
            break;

          case UNSPEC_LTREL_BASE:
            if (XVECLEN (indx, 0) == 1)
              indx = fake_pool_base, literal_pool = true;
            else
              indx = XVECEXP (indx, 0, 1);
            break;

          default:
            return false;
          }

      if (!REG_P (indx)
          || (GET_MODE (indx) != SImode
              && GET_MODE (indx) != Pmode))
        return false;

      if (REGNO (indx) == STACK_POINTER_REGNUM
          || REGNO (indx) == FRAME_POINTER_REGNUM
          || ((reload_completed || reload_in_progress)
              && frame_pointer_needed
              && REGNO (indx) == HARD_FRAME_POINTER_REGNUM)
          || REGNO (indx) == ARG_POINTER_REGNUM
          || (flag_pic
              && REGNO (indx) == PIC_OFFSET_TABLE_REGNUM))
        pointer = indx_ptr = true;

      if ((reload_completed || reload_in_progress)
          && indx == cfun->machine->base_reg)
        pointer = indx_ptr = literal_pool = true;
    }

  /* Prefer to use pointer as base, not index.  */
  if (base && indx && !base_ptr
      && (indx_ptr || (!REG_POINTER (base) && REG_POINTER (indx))))
    {
      rtx tmp = base;
      base = indx;
      indx = tmp;
    }

  /* Validate displacement.  */
  if (!disp)
    {
      /* If virtual registers are involved, the displacement will change later
         anyway as the virtual registers get eliminated.  This could make a
         valid displacement invalid, but it is more likely to make an invalid
         displacement valid, because we sometimes access the register save area
         via negative offsets to one of those registers.
         Thus we don't check the displacement for validity here.  If after
         elimination the displacement turns out to be invalid after all,
         this is fixed up by reload in any case.  */
      /* LRA maintains always displacements up to date and we need to
         know the displacement is right during all LRA not only at the
         final elimination.  */
      if (lra_in_progress
          || (base != arg_pointer_rtx
              && indx != arg_pointer_rtx
              && base != return_address_pointer_rtx
              && indx != return_address_pointer_rtx
              && base != frame_pointer_rtx
              && indx != frame_pointer_rtx
              && base != virtual_stack_vars_rtx
              && indx != virtual_stack_vars_rtx))
        if (!DISP_IN_RANGE (offset))
          return false;
    }
  else
    {
      /* All the special cases are pointers.  */
      pointer = true;

      /* In the small-PIC case, the linker converts @GOT
         and @GOTNTPOFF offsets to possible displacements.  */
      if (GET_CODE (disp) == UNSPEC
          && (XINT (disp, 1) == UNSPEC_GOT
              || XINT (disp, 1) == UNSPEC_GOTNTPOFF)
          && flag_pic == 1)
        {
          ;
        }

      /* Accept pool label offsets.  */
      else if (GET_CODE (disp) == UNSPEC
               && XINT (disp, 1) == UNSPEC_POOL_OFFSET)
        ;

      /* Accept literal pool references.  */
      else if (GET_CODE (disp) == UNSPEC
               && XINT (disp, 1) == UNSPEC_LTREL_OFFSET)
        {
          /* In case CSE pulled a non literal pool reference out of
             the pool we have to reject the address.  This is
             especially important when loading the GOT pointer on non
             zarch CPUs.  In this case the literal pool contains an lt
             relative offset to the _GLOBAL_OFFSET_TABLE_ label which
             will most likely exceed the displacement.  */
          if (GET_CODE (XVECEXP (disp, 0, 0)) != SYMBOL_REF
              || !CONSTANT_POOL_ADDRESS_P (XVECEXP (disp, 0, 0)))
            return false;

          orig_disp = gen_rtx_CONST (Pmode, disp);
          if (offset)
            {
              /* If we have an offset, make sure it does not
                 exceed the size of the constant pool entry.  */
              rtx sym = XVECEXP (disp, 0, 0);
              if (offset >= GET_MODE_SIZE (get_pool_mode (sym)))
                return false;

              orig_disp = plus_constant (Pmode, orig_disp, offset);
            }
        }

      else
        return false;
    }

  if (!base && !indx)
    pointer = true;

  if (out)
    {
      out->base = base;
      out->indx = indx;
      out->disp = orig_disp;
      out->pointer = pointer;
      out->literal_pool = literal_pool;
    }

  return true;
}

/* Decompose a RTL expression OP for a shift count into its components,
   and return the base register in BASE and the offset in OFFSET.

   Return true if OP is a valid shift count, false if not.  */

bool
s390_decompose_shift_count (rtx op, rtx *base, HOST_WIDE_INT *offset)
{
  HOST_WIDE_INT off = 0;

  /* We can have an integer constant, an address register,
     or a sum of the two.  */
  if (GET_CODE (op) == CONST_INT)
    {
      off = INTVAL (op);
      op = NULL_RTX;
    }
  if (op && GET_CODE (op) == PLUS && GET_CODE (XEXP (op, 1)) == CONST_INT)
    {
      off = INTVAL (XEXP (op, 1));
      op = XEXP (op, 0);
    }
  while (op && GET_CODE (op) == SUBREG)
    op = SUBREG_REG (op);

  if (op && GET_CODE (op) != REG)
    return false;

  if (offset)
    *offset = off;
  if (base)
    *base = op;

   return true;
}


/* Return true if CODE is a valid address without index.  */

bool
s390_legitimate_address_without_index_p (rtx op)
{
  struct s390_address addr;

  if (!s390_decompose_address (XEXP (op, 0), &addr))
    return false;
  if (addr.indx)
    return false;

  return true;
}


/* Return TRUE if ADDR is an operand valid for a load/store relative
   instruction.  Be aware that the alignment of the operand needs to
   be checked separately.
   Valid addresses are single references or a sum of a reference and a
   constant integer. Return these parts in SYMREF and ADDEND.  You can
   pass NULL in REF and/or ADDEND if you are not interested in these
   values.  Literal pool references are *not* considered symbol
   references.  */

static bool
s390_loadrelative_operand_p (rtx addr, rtx *symref, HOST_WIDE_INT *addend)
{
  HOST_WIDE_INT tmpaddend = 0;

  if (GET_CODE (addr) == CONST)
    addr = XEXP (addr, 0);

  if (GET_CODE (addr) == PLUS)
    {
      if (!CONST_INT_P (XEXP (addr, 1)))
        return false;

      tmpaddend = INTVAL (XEXP (addr, 1));
      addr = XEXP (addr, 0);
    }

  if ((GET_CODE (addr) == SYMBOL_REF && !CONSTANT_POOL_ADDRESS_P (addr))
      || (GET_CODE (addr) == UNSPEC
          && (XINT (addr, 1) == UNSPEC_GOTENT
              || (TARGET_CPU_ZARCH && XINT (addr, 1) == UNSPEC_PLT))))
    {
      if (symref)
        *symref = addr;
      if (addend)
        *addend = tmpaddend;

      return true;
    }
  return false;
}

/* Return true if the address in OP is valid for constraint letter C
   if wrapped in a MEM rtx.  Set LIT_POOL_OK to true if it literal
   pool MEMs should be accepted.  Only the Q, R, S, T constraint
   letters are allowed for C.  */

static int
s390_check_qrst_address (char c, rtx op, bool lit_pool_ok)
{
  struct s390_address addr;
  bool decomposed = false;

  /* This check makes sure that no symbolic address (except literal
     pool references) are accepted by the R or T constraints.  */
  if (s390_loadrelative_operand_p (op, NULL, NULL))
    return 0;

  /* Ensure literal pool references are only accepted if LIT_POOL_OK.  */
  if (!lit_pool_ok)
    {
      if (!s390_decompose_address (op, &addr))
        return 0;
      if (addr.literal_pool)
        return 0;
      decomposed = true;
    }

  switch (c)
    {
    case 'Q': /* no index short displacement */
      if (!decomposed && !s390_decompose_address (op, &addr))
        return 0;
      if (addr.indx)
        return 0;
      if (!s390_short_displacement (addr.disp))
        return 0;
      break;

    case 'R': /* with index short displacement */
      if (TARGET_LONG_DISPLACEMENT)
        {
          if (!decomposed && !s390_decompose_address (op, &addr))
            return 0;
          if (!s390_short_displacement (addr.disp))
            return 0;
        }
      /* Any invalid address here will be fixed up by reload,
         so accept it for the most generic constraint.  */
      break;

    case 'S': /* no index long displacement */
      if (!TARGET_LONG_DISPLACEMENT)
        return 0;
      if (!decomposed && !s390_decompose_address (op, &addr))
        return 0;
      if (addr.indx)
        return 0;
      if (s390_short_displacement (addr.disp))
        return 0;
      break;

    case 'T': /* with index long displacement */
      if (!TARGET_LONG_DISPLACEMENT)
        return 0;
      /* Any invalid address here will be fixed up by reload,
         so accept it for the most generic constraint.  */
      if ((decomposed || s390_decompose_address (op, &addr))
          && s390_short_displacement (addr.disp))
        return 0;
      break;
    default:
      return 0;
    }
  return 1;
}


/* Evaluates constraint strings described by the regular expression
   ([A|B|Z](Q|R|S|T))|U|W|Y and returns 1 if OP is a valid operand for
   the constraint given in STR, or 0 else.  */

int
s390_mem_constraint (const char *str, rtx op)
{
  char c = str[0];

  switch (c)
    {
    case 'A':
      /* Check for offsettable variants of memory constraints.  */
      if (!MEM_P (op) || MEM_VOLATILE_P (op))
        return 0;
      if ((reload_completed || reload_in_progress)
          ? !offsettable_memref_p (op) : !offsettable_nonstrict_memref_p (op))
        return 0;
      return s390_check_qrst_address (str[1], XEXP (op, 0), true);
    case 'B':
      /* Check for non-literal-pool variants of memory constraints.  */
      if (!MEM_P (op))
        return 0;
      return s390_check_qrst_address (str[1], XEXP (op, 0), false);
    case 'Q':
    case 'R':
    case 'S':
    case 'T':
      if (GET_CODE (op) != MEM)
        return 0;
      return s390_check_qrst_address (c, XEXP (op, 0), true);
    case 'U':
      return (s390_check_qrst_address ('Q', op, true)
              || s390_check_qrst_address ('R', op, true));
    case 'W':
      return (s390_check_qrst_address ('S', op, true)
              || s390_check_qrst_address ('T', op, true));
    case 'Y':
      /* Simply check for the basic form of a shift count.  Reload will
         take care of making sure we have a proper base register.  */
      if (!s390_decompose_shift_count (op, NULL, NULL))
        return 0;
      break;
    case 'Z':
      return s390_check_qrst_address (str[1], op, true);
    default:
      return 0;
    }
  return 1;
}


/* Evaluates constraint strings starting with letter O.  Input
   parameter C is the second letter following the "O" in the constraint
   string. Returns 1 if VALUE meets the respective constraint and 0
   otherwise.  */

int
s390_O_constraint_str (const char c, HOST_WIDE_INT value)
{
  if (!TARGET_EXTIMM)
    return 0;

  switch (c)
    {
    case 's':
      return trunc_int_for_mode (value, SImode) == value;

    case 'p':
      return value == 0
        || s390_single_part (GEN_INT (value), DImode, SImode, 0) == 1;

    case 'n':
      return s390_single_part (GEN_INT (value - 1), DImode, SImode, -1) == 1;

    default:
      gcc_unreachable ();
    }
}


/* Evaluates constraint strings starting with letter N.  Parameter STR
   contains the letters following letter "N" in the constraint string.
   Returns true if VALUE matches the constraint.  */

int
s390_N_constraint_str (const char *str, HOST_WIDE_INT value)
{
  machine_mode mode, part_mode;
  int def;
  int part, part_goal;


  if (str[0] == 'x')
    part_goal = -1;
  else
    part_goal = str[0] - '0';

  switch (str[1])
    {
    case 'Q':
      part_mode = QImode;
      break;
    case 'H':
      part_mode = HImode;
      break;
    case 'S':
      part_mode = SImode;
      break;
    default:
      return 0;
    }

  switch (str[2])
    {
    case 'H':
      mode = HImode;
      break;
    case 'S':
      mode = SImode;
      break;
    case 'D':
      mode = DImode;
      break;
    default:
      return 0;
    }

  switch (str[3])
    {
    case '0':
      def = 0;
      break;
    case 'F':
      def = -1;
      break;
    default:
      return 0;
    }

  if (GET_MODE_SIZE (mode) <= GET_MODE_SIZE (part_mode))
    return 0;

  part = s390_single_part (GEN_INT (value), mode, part_mode, def);
  if (part < 0)
    return 0;
  if (part_goal != -1 && part_goal != part)
    return 0;

  return 1;
}


/* Returns true if the input parameter VALUE is a float zero.  */

int
s390_float_const_zero_p (rtx value)
{
  return (GET_MODE_CLASS (GET_MODE (value)) == MODE_FLOAT
          && value == CONST0_RTX (GET_MODE (value)));
}

/* Implement TARGET_REGISTER_MOVE_COST.  */

static int
s390_register_move_cost (machine_mode mode ATTRIBUTE_UNUSED,
                         reg_class_t from, reg_class_t to)
{
  /* On s390, copy between fprs and gprs is expensive as long as no
     ldgr/lgdr can be used.  */
  if ((!TARGET_Z10 || GET_MODE_SIZE (mode) != 8)
      && ((reg_classes_intersect_p (from, GENERAL_REGS)
           && reg_classes_intersect_p (to, FP_REGS))
          || (reg_classes_intersect_p (from, FP_REGS)
              && reg_classes_intersect_p (to, GENERAL_REGS))))
    return 10;

  return 1;
}

/* Implement TARGET_MEMORY_MOVE_COST.  */

static int
s390_memory_move_cost (machine_mode mode ATTRIBUTE_UNUSED,
                       reg_class_t rclass ATTRIBUTE_UNUSED,
                       bool in ATTRIBUTE_UNUSED)
{
  return 1;
}

/* Compute a (partial) cost for rtx X.  Return true if the complete
   cost has been computed, and false if subexpressions should be
   scanned.  In either case, *TOTAL contains the cost result.
   CODE contains GET_CODE (x), OUTER_CODE contains the code
   of the superexpression of x.  */

static bool
s390_rtx_costs (rtx x, int code, int outer_code, int opno ATTRIBUTE_UNUSED,
                int *total, bool speed ATTRIBUTE_UNUSED)
{
  switch (code)
    {
    case CONST:
    case CONST_INT:
    case LABEL_REF:
    case SYMBOL_REF:
    case CONST_DOUBLE:
    case MEM:
      *total = 0;
      return true;

    case ASHIFT:
    case ASHIFTRT:
    case LSHIFTRT:
    case ROTATE:
    case ROTATERT:
    case AND:
    case IOR:
    case XOR:
    case NEG:
    case NOT:
      *total = COSTS_N_INSNS (1);
      return false;

    case PLUS:
    case MINUS:
      *total = COSTS_N_INSNS (1);
      return false;

    case MULT:
      switch (GET_MODE (x))
        {
        case SImode:
          {
            rtx left = XEXP (x, 0);
            rtx right = XEXP (x, 1);
            if (GET_CODE (right) == CONST_INT
                && CONST_OK_FOR_K (INTVAL (right)))
              *total = s390_cost->mhi;
            else if (GET_CODE (left) == SIGN_EXTEND)
              *total = s390_cost->mh;
            else
              *total = s390_cost->ms;  /* msr, ms, msy */
            break;
          }
        case DImode:
          {
            rtx left = XEXP (x, 0);
            rtx right = XEXP (x, 1);
            if (TARGET_ZARCH)
              {
                if (GET_CODE (right) == CONST_INT
                    && CONST_OK_FOR_K (INTVAL (right)))
                  *total = s390_cost->mghi;
                else if (GET_CODE (left) == SIGN_EXTEND)
                  *total = s390_cost->msgf;
                else
                  *total = s390_cost->msg;  /* msgr, msg */
              }
            else /* TARGET_31BIT */
              {
                if (GET_CODE (left) == SIGN_EXTEND
                    && GET_CODE (right) == SIGN_EXTEND)
                  /* mulsidi case: mr, m */
                  *total = s390_cost->m;
                else if (GET_CODE (left) == ZERO_EXTEND
                         && GET_CODE (right) == ZERO_EXTEND
                         && TARGET_CPU_ZARCH)
                  /* umulsidi case: ml, mlr */
                  *total = s390_cost->ml;
                else
                  /* Complex calculation is required.  */
                  *total = COSTS_N_INSNS (40);
              }
            break;
          }
        case SFmode:
        case DFmode:
          *total = s390_cost->mult_df;
          break;
        case TFmode:
          *total = s390_cost->mxbr;
          break;
        default:
          return false;
        }
      return false;

    case FMA:
      switch (GET_MODE (x))
        {
        case DFmode:
          *total = s390_cost->madbr;
          break;
        case SFmode:
          *total = s390_cost->maebr;
          break;
        default:
          return false;
        }
      /* Negate in the third argument is free: FMSUB.  */
      if (GET_CODE (XEXP (x, 2)) == NEG)
        {
          *total += (rtx_cost (XEXP (x, 0), FMA, 0, speed)
                     + rtx_cost (XEXP (x, 1), FMA, 1, speed)
                     + rtx_cost (XEXP (XEXP (x, 2), 0), FMA, 2, speed));
          return true;
        }
      return false;

    case UDIV:
    case UMOD:
      if (GET_MODE (x) == TImode)              /* 128 bit division */
        *total = s390_cost->dlgr;
      else if (GET_MODE (x) == DImode)
        {
          rtx right = XEXP (x, 1);
          if (GET_CODE (right) == ZERO_EXTEND) /* 64 by 32 bit division */
            *total = s390_cost->dlr;
          else                                 /* 64 by 64 bit division */
            *total = s390_cost->dlgr;
        }
      else if (GET_MODE (x) == SImode)         /* 32 bit division */
        *total = s390_cost->dlr;
      return false;

    case DIV:
    case MOD:
      if (GET_MODE (x) == DImode)
        {
          rtx right = XEXP (x, 1);
          if (GET_CODE (right) == ZERO_EXTEND) /* 64 by 32 bit division */
            if (TARGET_ZARCH)
              *total = s390_cost->dsgfr;
            else
              *total = s390_cost->dr;
          else                                 /* 64 by 64 bit division */
            *total = s390_cost->dsgr;
        }
      else if (GET_MODE (x) == SImode)         /* 32 bit division */
        *total = s390_cost->dlr;
      else if (GET_MODE (x) == SFmode)
        {
          *total = s390_cost->debr;
        }
      else if (GET_MODE (x) == DFmode)
        {
          *total = s390_cost->ddbr;
        }
      else if (GET_MODE (x) == TFmode)
        {
          *total = s390_cost->dxbr;
        }
      return false;

    case SQRT:
      if (GET_MODE (x) == SFmode)
        *total = s390_cost->sqebr;
      else if (GET_MODE (x) == DFmode)
        *total = s390_cost->sqdbr;
      else /* TFmode */
        *total = s390_cost->sqxbr;
      return false;

    case SIGN_EXTEND:
    case ZERO_EXTEND:
      if (outer_code == MULT || outer_code == DIV || outer_code == MOD
          || outer_code == PLUS || outer_code == MINUS
          || outer_code == COMPARE)
        *total = 0;
      return false;

    case COMPARE:
      *total = COSTS_N_INSNS (1);
      if (GET_CODE (XEXP (x, 0)) == AND
          && GET_CODE (XEXP (x, 1)) == CONST_INT
          && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
        {
          rtx op0 = XEXP (XEXP (x, 0), 0);
          rtx op1 = XEXP (XEXP (x, 0), 1);
          rtx op2 = XEXP (x, 1);

          if (memory_operand (op0, GET_MODE (op0))
              && s390_tm_ccmode (op1, op2, 0) != VOIDmode)
            return true;
          if (register_operand (op0, GET_MODE (op0))
              && s390_tm_ccmode (op1, op2, 1) != VOIDmode)
            return true;
        }
      return false;

    default:
      return false;
    }
}

/* Return the cost of an address rtx ADDR.  */

static int
s390_address_cost (rtx addr, machine_mode mode ATTRIBUTE_UNUSED,
                   addr_space_t as ATTRIBUTE_UNUSED,
                   bool speed ATTRIBUTE_UNUSED)
{
  struct s390_address ad;
  if (!s390_decompose_address (addr, &ad))
    return 1000;

  return ad.indx? COSTS_N_INSNS (1) + 1 : COSTS_N_INSNS (1);
}

/* If OP is a SYMBOL_REF of a thread-local symbol, return its TLS mode,
   otherwise return 0.  */

int
tls_symbolic_operand (rtx op)
{
  if (GET_CODE (op) != SYMBOL_REF)
    return 0;
  return SYMBOL_REF_TLS_MODEL (op);
}
\f
/* Split DImode access register reference REG (on 64-bit) into its constituent
   low and high parts, and store them into LO and HI.  Note that gen_lowpart/
   gen_highpart cannot be used as they assume all registers are word-sized,
   while our access registers have only half that size.  */

void
s390_split_access_reg (rtx reg, rtx *lo, rtx *hi)
{
  gcc_assert (TARGET_64BIT);
  gcc_assert (ACCESS_REG_P (reg));
  gcc_assert (GET_MODE (reg) == DImode);
  gcc_assert (!(REGNO (reg) & 1));

  *lo = gen_rtx_REG (SImode, REGNO (reg) + 1);
  *hi = gen_rtx_REG (SImode, REGNO (reg));
}

/* Return true if OP contains a symbol reference */

bool
symbolic_reference_mentioned_p (rtx op)
{
  const char *fmt;
  int i;

  if (GET_CODE (op) == SYMBOL_REF || GET_CODE (op) == LABEL_REF)
    return 1;

  fmt = GET_RTX_FORMAT (GET_CODE (op));
  for (i = GET_RTX_LENGTH (GET_CODE (op)) - 1; i >= 0; i--)
    {
      if (fmt[i] == 'E')
        {
          int j;

          for (j = XVECLEN (op, i) - 1; j >= 0; j--)
            if (symbolic_reference_mentioned_p (XVECEXP (op, i, j)))
              return 1;
        }

      else if (fmt[i] == 'e' && symbolic_reference_mentioned_p (XEXP (op, i)))
        return 1;
    }

  return 0;
}

/* Return true if OP contains a reference to a thread-local symbol.  */

bool
tls_symbolic_reference_mentioned_p (rtx op)
{
  const char *fmt;
  int i;

  if (GET_CODE (op) == SYMBOL_REF)
    return tls_symbolic_operand (op);

  fmt = GET_RTX_FORMAT (GET_CODE (op));
  for (i = GET_RTX_LENGTH (GET_CODE (op)) - 1; i >= 0; i--)
    {
      if (fmt[i] == 'E')
        {
          int j;

          for (j = XVECLEN (op, i) - 1; j >= 0; j--)
            if (tls_symbolic_reference_mentioned_p (XVECEXP (op, i, j)))
              return true;
        }

      else if (fmt[i] == 'e' && tls_symbolic_reference_mentioned_p (XEXP (op, i)))
        return true;
    }

  return false;
}


/* Return true if OP is a legitimate general operand when
   generating PIC code.  It is given that flag_pic is on
   and that OP satisfies CONSTANT_P or is a CONST_DOUBLE.  */

int
legitimate_pic_operand_p (rtx op)
{
  /* Accept all non-symbolic constants.  */
  if (!SYMBOLIC_CONST (op))
    return 1;

  /* Reject everything else; must be handled
     via emit_symbolic_move.  */
  return 0;
}

/* Returns true if the constant value OP is a legitimate general operand.
   It is given that OP satisfies CONSTANT_P or is a CONST_DOUBLE.  */

static bool
s390_legitimate_constant_p (machine_mode mode, rtx op)
{
  /* Accept all non-symbolic constants.  */
  if (!SYMBOLIC_CONST (op))
    return 1;

  /* Accept immediate LARL operands.  */
  if (TARGET_CPU_ZARCH && larl_operand (op, mode))
    return 1;

  /* Thread-local symbols are never legal constants.  This is
     so that emit_call knows that computing such addresses
     might require a function call.  */
  if (TLS_SYMBOLIC_CONST (op))
    return 0;

  /* In the PIC case, symbolic constants must *not* be
     forced into the literal pool.  We accept them here,
     so that they will be handled by emit_symbolic_move.  */
  if (flag_pic)
    return 1;

  /* All remaining non-PIC symbolic constants are
     forced into the literal pool.  */
  return 0;
}

/* Determine if it's legal to put X into the constant pool.  This
   is not possible if X contains the address of a symbol that is
   not constant (TLS) or not known at final link time (PIC).  */

static bool
s390_cannot_force_const_mem (machine_mode mode, rtx x)
{
  switch (GET_CODE (x))
    {
    case CONST_INT:
    case CONST_DOUBLE:
      /* Accept all non-symbolic constants.  */
      return false;

    case LABEL_REF:
      /* Labels are OK iff we are non-PIC.  */
      return flag_pic != 0;

    case SYMBOL_REF:
      /* 'Naked' TLS symbol references are never OK,
         non-TLS symbols are OK iff we are non-PIC.  */
      if (tls_symbolic_operand (x))
        return true;
      else
        return flag_pic != 0;

    case CONST:
      return s390_cannot_force_const_mem (mode, XEXP (x, 0));
    case PLUS:
    case MINUS:
      return s390_cannot_force_const_mem (mode, XEXP (x, 0))
             || s390_cannot_force_const_mem (mode, XEXP (x, 1));

    case UNSPEC:
      switch (XINT (x, 1))
        {
        /* Only lt-relative or GOT-relative UNSPECs are OK.  */
        case UNSPEC_LTREL_OFFSET:
        case UNSPEC_GOT:
        case UNSPEC_GOTOFF:
        case UNSPEC_PLTOFF:
        case UNSPEC_TLSGD:
        case UNSPEC_TLSLDM:
        case UNSPEC_NTPOFF:
        case UNSPEC_DTPOFF:
        case UNSPEC_GOTNTPOFF:
        case UNSPEC_INDNTPOFF:
          return false;

        /* If the literal pool shares the code section, be put
           execute template placeholders into the pool as well.  */
        case UNSPEC_INSN:
          return TARGET_CPU_ZARCH;

        default:
          return true;
        }
      break;

    default:
      gcc_unreachable ();
    }
}

/* Returns true if the constant value OP is a legitimate general
   operand during and after reload.  The difference to
   legitimate_constant_p is that this function will not accept
   a constant that would need to be forced to the literal pool
   before it can be used as operand.
   This function accepts all constants which can be loaded directly
   into a GPR.  */

bool
legitimate_reload_constant_p (rtx op)
{
  /* Accept la(y) operands.  */
  if (GET_CODE (op) == CONST_INT
      && DISP_IN_RANGE (INTVAL (op)))
    return true;

  /* Accept l(g)hi/l(g)fi operands.  */
  if (GET_CODE (op) == CONST_INT
      && (CONST_OK_FOR_K (INTVAL (op)) || CONST_OK_FOR_Os (INTVAL (op))))
    return true;

  /* Accept lliXX operands.  */
  if (TARGET_ZARCH
      && GET_CODE (op) == CONST_INT
      && trunc_int_for_mode (INTVAL (op), word_mode) == INTVAL (op)
      && s390_single_part (op, word_mode, HImode, 0) >= 0)
  return true;

  if (TARGET_EXTIMM
      && GET_CODE (op) == CONST_INT
      && trunc_int_for_mode (INTVAL (op), word_mode) == INTVAL (op)
      && s390_single_part (op, word_mode, SImode, 0) >= 0)
    return true;

  /* Accept larl operands.  */
  if (TARGET_CPU_ZARCH
      && larl_operand (op, VOIDmode))
    return true;

  /* Accept floating-point zero operands that fit into a single GPR.  */
  if (GET_CODE (op) == CONST_DOUBLE
      && s390_float_const_zero_p (op)
      && GET_MODE_SIZE (GET_MODE (op)) <= UNITS_PER_WORD)
    return true;

  /* Accept double-word operands that can be split.  */
  if (GET_CODE (op) == CONST_INT
      && trunc_int_for_mode (INTVAL (op), word_mode) != INTVAL (op))
    {
      machine_mode dword_mode = word_mode == SImode ? DImode : TImode;
      rtx hi = operand_subword (op, 0, 0, dword_mode);
      rtx lo = operand_subword (op, 1, 0, dword_mode);
      return legitimate_reload_constant_p (hi)
             && legitimate_reload_constant_p (lo);
    }

  /* Everything else cannot be handled without reload.  */
  return false;
}

/* Returns true if the constant value OP is a legitimate fp operand
   during and after reload.
   This function accepts all constants which can be loaded directly
   into an FPR.  */

static bool
legitimate_reload_fp_constant_p (rtx op)
{
  /* Accept floating-point zero operands if the load zero instruction
     can be used.  Prior to z196 the load fp zero instruction caused a
     performance penalty if the result is used as BFP number.  */
  if (TARGET_Z196
      && GET_CODE (op) == CONST_DOUBLE
      && s390_float_const_zero_p (op))
    return true;

  return false;
}

/* Given an rtx OP being reloaded into a reg required to be in class RCLASS,
   return the class of reg to actually use.  */

static reg_class_t
s390_preferred_reload_class (rtx op, reg_class_t rclass)
{
  switch (GET_CODE (op))
    {
      /* Constants we cannot reload into general registers
         must be forced into the literal pool.  */
      case CONST_DOUBLE:
      case CONST_INT:
        if (reg_class_subset_p (GENERAL_REGS, rclass)
            && legitimate_reload_constant_p (op))
          return GENERAL_REGS;
        else if (reg_class_subset_p (ADDR_REGS, rclass)
                 && legitimate_reload_constant_p (op))
          return ADDR_REGS;
        else if (reg_class_subset_p (FP_REGS, rclass)
                 && legitimate_reload_fp_constant_p (op))
          return FP_REGS;
        return NO_REGS;

      /* If a symbolic constant or a PLUS is reloaded,
         it is most likely being used as an address, so
         prefer ADDR_REGS.  If 'class' is not a superset
         of ADDR_REGS, e.g. FP_REGS, reject this reload.  */
      case CONST:
        /* Symrefs cannot be pushed into the literal pool with -fPIC
           so we *MUST NOT* return NO_REGS for these cases
           (s390_cannot_force_const_mem will return true).  

           On the other hand we MUST return NO_REGS for symrefs with
           invalid addend which might have been pushed to the literal
           pool (no -fPIC).  Usually we would expect them to be
           handled via secondary reload but this does not happen if
           they are used as literal pool slot replacement in reload
           inheritance (see emit_input_reload_insns).  */
        if (TARGET_CPU_ZARCH
            && GET_CODE (XEXP (op, 0)) == PLUS
            && GET_CODE (XEXP (XEXP(op, 0), 0)) == SYMBOL_REF
            && GET_CODE (XEXP (XEXP(op, 0), 1)) == CONST_INT)
          {
            if (flag_pic && reg_class_subset_p (ADDR_REGS, rclass))
              return ADDR_REGS;
            else
              return NO_REGS;
          }
        /* fallthrough */
      case LABEL_REF:
      case SYMBOL_REF:
        if (!legitimate_reload_constant_p (op))
          return NO_REGS;
        /* fallthrough */
      case PLUS:
        /* load address will be used.  */
        if (reg_class_subset_p (ADDR_REGS, rclass))
          return ADDR_REGS;
        else
          return NO_REGS;

      default:
        break;
    }

  return rclass;
}

/* Return true if ADDR is SYMBOL_REF + addend with addend being a
   multiple of ALIGNMENT and the SYMBOL_REF being naturally
   aligned.  */

bool
s390_check_symref_alignment (rtx addr, HOST_WIDE_INT alignment)
{
  HOST_WIDE_INT addend;
  rtx symref;

  if (!s390_loadrelative_operand_p (addr, &symref, &addend))
    return false;

  if (addend & (alignment - 1))
    return false;

  if (GET_CODE (symref) == SYMBOL_REF
      && !SYMBOL_REF_NOT_NATURALLY_ALIGNED_P (symref))
    return true;

  if (GET_CODE (symref) == UNSPEC
      && alignment <= UNITS_PER_LONG)
    return true;

  return false;
}

/* ADDR is moved into REG using larl.  If ADDR isn't a valid larl
   operand SCRATCH is used to reload the even part of the address and
   adding one.  */

void
s390_reload_larl_operand (rtx reg, rtx addr, rtx scratch)
{
  HOST_WIDE_INT addend;
  rtx symref;

  if (!s390_loadrelative_operand_p (addr, &symref, &addend))
    gcc_unreachable ();

  if (!(addend & 1))
    /* Easy case.  The addend is even so larl will do fine.  */
    emit_move_insn (reg, addr);
  else
    {
      /* We can leave the scratch register untouched if the target
         register is a valid base register.  */
      if (REGNO (reg) < FIRST_PSEUDO_REGISTER
          && REGNO_REG_CLASS (REGNO (reg)) == ADDR_REGS)
        scratch = reg;

      gcc_assert (REGNO (scratch) < FIRST_PSEUDO_REGISTER);
      gcc_assert (REGNO_REG_CLASS (REGNO (scratch)) == ADDR_REGS);

      if (addend != 1)
        emit_move_insn (scratch,
                        gen_rtx_CONST (Pmode,
                                       gen_rtx_PLUS (Pmode, symref,
                                                     GEN_INT (addend - 1))));
      else
        emit_move_insn (scratch, symref);

      /* Increment the address using la in order to avoid clobbering cc.  */
      s390_load_address (reg, gen_rtx_PLUS (Pmode, scratch, const1_rtx));
    }
}

/* Generate what is necessary to move between REG and MEM using
   SCRATCH.  The direction is given by TOMEM.  */

void
s390_reload_symref_address (rtx reg, rtx mem, rtx scratch, bool tomem)
{
  /* Reload might have pulled a constant out of the literal pool.
     Force it back in.  */
  if (CONST_INT_P (mem) || GET_CODE (mem) == CONST_DOUBLE
      || GET_CODE (mem) == CONST)
    mem = force_const_mem (GET_MODE (reg), mem);

  gcc_assert (MEM_P (mem));

  /* For a load from memory we can leave the scratch register
     untouched if the target register is a valid base register.  */
  if (!tomem
      && REGNO (reg) < FIRST_PSEUDO_REGISTER
      && REGNO_REG_CLASS (REGNO (reg)) == ADDR_REGS
      && GET_MODE (reg) == GET_MODE (scratch))
    scratch = reg;

  /* Load address into scratch register.  Since we can't have a
     secondary reload for a secondary reload we have to cover the case
     where larl would need a secondary reload here as well.  */
  s390_reload_larl_operand (scratch, XEXP (mem, 0), scratch);

  /* Now we can use a standard load/store to do the move.  */
  if (tomem)
    emit_move_insn (replace_equiv_address (mem, scratch), reg);
  else
    emit_move_insn (reg, replace_equiv_address (mem, scratch));
}

/* Inform reload about cases where moving X with a mode MODE to a register in
   RCLASS requires an extra scratch or immediate register.  Return the class
   needed for the immediate register.  */

static reg_class_t
s390_secondary_reload (bool in_p, rtx x, reg_class_t rclass_i,
                       machine_mode mode, secondary_reload_info *sri)
{
  enum reg_class rclass = (enum reg_class) rclass_i;

  /* Intermediate register needed.  */
  if (reg_classes_intersect_p (CC_REGS, rclass))
    return GENERAL_REGS;

  if (TARGET_Z10)
    {
      HOST_WIDE_INT offset;
      rtx symref;

      /* On z10 several optimizer steps may generate larl operands with
         an odd addend.  */
      if (in_p
          && s390_loadrelative_operand_p (x, &symref, &offset)
          && mode == Pmode
          && !SYMBOL_REF_ALIGN1_P (symref)
          && (offset & 1) == 1)
        sri->icode = ((mode == DImode) ? CODE_FOR_reloaddi_larl_odd_addend_z10
                      : CODE_FOR_reloadsi_larl_odd_addend_z10);

      /* On z10 we need a scratch register when moving QI, TI or floating
         point mode values from or to a memory location with a SYMBOL_REF
         or if the symref addend of a SI or DI move is not aligned to the
         width of the access.  */
      if (MEM_P (x)
          && s390_loadrelative_operand_p (XEXP (x, 0), NULL, NULL)
          && (mode == QImode || mode == TImode || FLOAT_MODE_P (mode)
              || (!TARGET_ZARCH && mode == DImode)
              || ((mode == HImode || mode == SImode || mode == DImode)
                  && (!s390_check_symref_alignment (XEXP (x, 0),
                                                    GET_MODE_SIZE (mode))))))
        {
#define __SECONDARY_RELOAD_CASE(M,m)                                    \
          case M##mode:                                                 \
            if (TARGET_64BIT)                                           \
              sri->icode = in_p ? CODE_FOR_reload##m##di_toreg_z10 :    \
                                  CODE_FOR_reload##m##di_tomem_z10;     \
            else                                                        \
              sri->icode = in_p ? CODE_FOR_reload##m##si_toreg_z10 :    \
                                  CODE_FOR_reload##m##si_tomem_z10;     \
          break;

          switch (GET_MODE (x))
            {
              __SECONDARY_RELOAD_CASE (QI, qi);
              __SECONDARY_RELOAD_CASE (HI, hi);
              __SECONDARY_RELOAD_CASE (SI, si);
              __SECONDARY_RELOAD_CASE (DI, di);
              __SECONDARY_RELOAD_CASE (TI, ti);
              __SECONDARY_RELOAD_CASE (SF, sf);
              __SECONDARY_RELOAD_CASE (DF, df);
              __SECONDARY_RELOAD_CASE (TF, tf);
              __SECONDARY_RELOAD_CASE (SD, sd);
              __SECONDARY_RELOAD_CASE (DD, dd);
              __SECONDARY_RELOAD_CASE (TD, td);

            default:
              gcc_unreachable ();
            }
#undef __SECONDARY_RELOAD_CASE
        }
    }

  /* We need a scratch register when loading a PLUS expression which
     is not a legitimate operand of the LOAD ADDRESS instruction.  */
  /* LRA can deal with transformation of plus op very well -- so we
     don't need to prompt LRA in this case.  */
  if (! lra_in_progress && in_p && s390_plus_operand (x, mode))
    sri->icode = (TARGET_64BIT ?
                  CODE_FOR_reloaddi_plus : CODE_FOR_reloadsi_plus);

  /* Performing a multiword move from or to memory we have to make sure the
     second chunk in memory is addressable without causing a displacement
     overflow.  If that would be the case we calculate the address in
     a scratch register.  */
  if (MEM_P (x)
      && GET_CODE (XEXP (x, 0)) == PLUS
      && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT
      && !DISP_IN_RANGE (INTVAL (XEXP (XEXP (x, 0), 1))
                         + GET_MODE_SIZE (mode) - 1))
    {
      /* For GENERAL_REGS a displacement overflow is no problem if occurring
         in a s_operand address since we may fallback to lm/stm.  So we only
         have to care about overflows in the b+i+d case.  */
      if ((reg_classes_intersect_p (GENERAL_REGS, rclass)
           && s390_class_max_nregs (GENERAL_REGS, mode) > 1
           && GET_CODE (XEXP (XEXP (x, 0), 0)) == PLUS)
          /* For FP_REGS no lm/stm is available so this check is triggered
             for displacement overflows in b+i+d and b+d like addresses.  */
          || (reg_classes_intersect_p (FP_REGS, rclass)
              && s390_class_max_nregs (FP_REGS, mode) > 1))
        {
          if (in_p)
            sri->icode = (TARGET_64BIT ?
                          CODE_FOR_reloaddi_nonoffmem_in :
                          CODE_FOR_reloadsi_nonoffmem_in);
          else
            sri->icode = (TARGET_64BIT ?
                          CODE_FOR_reloaddi_nonoffmem_out :
                          CODE_FOR_reloadsi_nonoffmem_out);
        }
    }

  /* A scratch address register is needed when a symbolic constant is
     copied to r0 compiling with -fPIC.  In other cases the target
     register might be used as temporary (see legitimize_pic_address).  */
  if (in_p && SYMBOLIC_CONST (x) && flag_pic == 2 && rclass != ADDR_REGS)
    sri->icode = (TARGET_64BIT ?
                  CODE_FOR_reloaddi_PIC_addr :
                  CODE_FOR_reloadsi_PIC_addr);

  /* Either scratch or no register needed.  */
  return NO_REGS;
}

/* Generate code to load SRC, which is PLUS that is not a
   legitimate operand for the LA instruction, into TARGET.
   SCRATCH may be used as scratch register.  */

void
s390_expand_plus_operand (rtx target, rtx src,
                          rtx scratch)
{
  rtx sum1, sum2;
  struct s390_address ad;

  /* src must be a PLUS; get its two operands.  */
  gcc_assert (GET_CODE (src) == PLUS);
  gcc_assert (GET_MODE (src) == Pmode);

  /* Check if any of the two operands is already scheduled
     for replacement by reload.  This can happen e.g. when
     float registers occur in an address.  */
  sum1 = find_replacement (&XEXP (src, 0));
  sum2 = find_replacement (&XEXP (src, 1));
  src = gen_rtx_PLUS (Pmode, sum1, sum2);

  /* If the address is already strictly valid, there's nothing to do.  */
  if (!s390_decompose_address (src, &ad)
      || (ad.base && !REGNO_OK_FOR_BASE_P (REGNO (ad.base)))
      || (ad.indx && !REGNO_OK_FOR_INDEX_P (REGNO (ad.indx))))
    {
      /* Otherwise, one of the operands cannot be an address register;
         we reload its value into the scratch register.  */
      if (true_regnum (sum1) < 1 || true_regnum (sum1) > 15)
        {
          emit_move_insn (scratch, sum1);
          sum1 = scratch;
        }
      if (true_regnum (sum2) < 1 || true_regnum (sum2) > 15)
        {
          emit_move_insn (scratch, sum2);
          sum2 = scratch;
        }

      /* According to the way these invalid addresses are generated
         in reload.c, it should never happen (at least on s390) that
         *neither* of the PLUS components, after find_replacements
         was applied, is an address register.  */
      if (sum1 == scratch && sum2 == scratch)
        {
          debug_rtx (src);
          gcc_unreachable ();
        }

      src = gen_rtx_PLUS (Pmode, sum1, sum2);
    }

  /* Emit the LOAD ADDRESS pattern.  Note that reload of PLUS
     is only ever performed on addresses, so we can mark the
     sum as legitimate for LA in any case.  */
  s390_load_address (target, src);
}


/* Return true if ADDR is a valid memory address.
   STRICT specifies whether strict register checking applies.  */

static bool
s390_legitimate_address_p (machine_mode mode, rtx addr, bool strict)
{
  struct s390_address ad;

  if (TARGET_Z10
      && larl_operand (addr, VOIDmode)
      && (mode == VOIDmode
          || s390_check_symref_alignment (addr, GET_MODE_SIZE (mode))))
    return true;

  if (!s390_decompose_address (addr, &ad))
    return false;

  if (strict)
    {
      if (ad.base && !REGNO_OK_FOR_BASE_P (REGNO (ad.base)))
        return false;

      if (ad.indx && !REGNO_OK_FOR_INDEX_P (REGNO (ad.indx)))
        return false;
    }
  else
    {
      if (ad.base
          && !(REGNO (ad.base) >= FIRST_PSEUDO_REGISTER
               || REGNO_REG_CLASS (REGNO (ad.base)) == ADDR_REGS))
        return false;

      if (ad.indx
          && !(REGNO (ad.indx) >= FIRST_PSEUDO_REGISTER
               || REGNO_REG_CLASS (REGNO (ad.indx)) == ADDR_REGS))
          return false;
    }
  return true;
}

/* Return true if OP is a valid operand for the LA instruction.
   In 31-bit, we need to prove that the result is used as an
   address, as LA performs only a 31-bit addition.  */

bool
legitimate_la_operand_p (rtx op)
{
  struct s390_address addr;
  if (!s390_decompose_address (op, &addr))
    return false;

  return (TARGET_64BIT || addr.pointer);
}

/* Return true if it is valid *and* preferable to use LA to
   compute the sum of OP1 and OP2.  */

bool
preferred_la_operand_p (rtx op1, rtx op2)
{
  struct s390_address addr;

  if (op2 != const0_rtx)
    op1 = gen_rtx_PLUS (Pmode, op1, op2);

  if (!s390_decompose_address (op1, &addr))
    return false;
  if (addr.base && !REGNO_OK_FOR_BASE_P (REGNO (addr.base)))
    return false;
  if (addr.indx && !REGNO_OK_FOR_INDEX_P (REGNO (addr.indx)))
    return false;

  /* Avoid LA instructions with index register on z196; it is
     preferable to use regular add instructions when possible.
     Starting with zEC12 the la with index register is "uncracked"
     again.  */
  if (addr.indx && s390_tune == PROCESSOR_2817_Z196)
    return false;

  if (!TARGET_64BIT && !addr.pointer)
    return false;

  if (addr.pointer)
    return true;

  if ((addr.base && REG_P (addr.base) && REG_POINTER (addr.base))
      || (addr.indx && REG_P (addr.indx) && REG_POINTER (addr.indx)))
    return true;

  return false;
}

/* Emit a forced load-address operation to load SRC into DST.
   This will use the LOAD ADDRESS instruction even in situations
   where legitimate_la_operand_p (SRC) returns false.  */

void
s390_load_address (rtx dst, rtx src)
{
  if (TARGET_64BIT)
    emit_move_insn (dst, src);
  else
    emit_insn (gen_force_la_31 (dst, src));
}

/* Return a legitimate reference for ORIG (an address) using the
   register REG.  If REG is 0, a new pseudo is generated.

   There are two types of references that must be handled:

   1. Global data references must load the address from the GOT, via
      the PIC reg.  An insn is emitted to do this load, and the reg is
      returned.

   2. Static data references, constant pool addresses, and code labels
      compute the address as an offset from the GOT, whose base is in
      the PIC reg.  Static data objects have SYMBOL_FLAG_LOCAL set to
      differentiate them from global data objects.  The returned
      address is the PIC reg + an unspec constant.

   TARGET_LEGITIMIZE_ADDRESS_P rejects symbolic references unless the PIC
   reg also appears in the address.  */

rtx
legitimize_pic_address (rtx orig, rtx reg)
{
  rtx addr = orig;
  rtx addend = const0_rtx;
  rtx new_rtx = orig;

  gcc_assert (!TLS_SYMBOLIC_CONST (addr));

  if (GET_CODE (addr) == CONST)
    addr = XEXP (addr, 0);

  if (GET_CODE (addr) == PLUS)
    {
      addend = XEXP (addr, 1);
      addr = XEXP (addr, 0);
    }

  if ((GET_CODE (addr) == LABEL_REF
       || (GET_CODE (addr) == SYMBOL_REF && SYMBOL_REF_LOCAL_P (addr))
       || (GET_CODE (addr) == UNSPEC &&
           (XINT (addr, 1) == UNSPEC_GOTENT
            || (TARGET_CPU_ZARCH && XINT (addr, 1) == UNSPEC_PLT))))
      && GET_CODE (addend) == CONST_INT)
    {
      /* This can be locally addressed.  */

      /* larl_operand requires UNSPECs to be wrapped in a const rtx.  */
      rtx const_addr = (GET_CODE (addr) == UNSPEC ?
                        gen_rtx_CONST (Pmode, addr) : addr);

      if (TARGET_CPU_ZARCH
          && larl_operand (const_addr, VOIDmode)
          && INTVAL (addend) < (HOST_WIDE_INT)1 << 31
          && INTVAL (addend) >= -((HOST_WIDE_INT)1 << 31))
        {
          if (INTVAL (addend) & 1)
            {
              /* LARL can't handle odd offsets, so emit a pair of LARL
                 and LA.  */
              rtx temp = reg? reg : gen_reg_rtx (Pmode);

              if (!DISP_IN_RANGE (INTVAL (addend)))
                {
                  HOST_WIDE_INT even = INTVAL (addend) - 1;
                  addr = gen_rtx_PLUS (Pmode, addr, GEN_INT (even));
                  addr = gen_rtx_CONST (Pmode, addr);
                  addend = const1_rtx;
                }

              emit_move_insn (temp, addr);
              new_rtx = gen_rtx_PLUS (Pmode, temp, addend);

              if (reg != 0)
                {
                  s390_load_address (reg, new_rtx);
                  new_rtx = reg;
                }
            }
          else
            {
              /* If the offset is even, we can just use LARL.  This
                 will happen automatically.  */
            }
        }
      else
        {
          /* No larl - Access local symbols relative to the GOT.  */

          rtx temp = reg? reg : gen_reg_rtx (Pmode);

          if (reload_in_progress || reload_completed)
            df_set_regs_ever_live (PIC_OFFSET_TABLE_REGNUM, true);

          addr = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_GOTOFF);
          if (addend != const0_rtx)
            addr = gen_rtx_PLUS (Pmode, addr, addend);
          addr = gen_rtx_CONST (Pmode, addr);
          addr = force_const_mem (Pmode, addr);
          emit_move_insn (temp, addr);

          new_rtx = gen_rtx_PLUS (Pmode, pic_offset_table_rtx, temp);
          if (reg != 0)
            {
              s390_load_address (reg, new_rtx);
              new_rtx = reg;
            }
        }
    }
  else if (GET_CODE (addr) == SYMBOL_REF && addend == const0_rtx)
    {
      /* A non-local symbol reference without addend.

         The symbol ref is wrapped into an UNSPEC to make sure the
         proper operand modifier (@GOT or @GOTENT) will be emitted.
         This will tell the linker to put the symbol into the GOT.

         Additionally the code dereferencing the GOT slot is emitted here.

         An addend to the symref needs to be added afterwards.
         legitimize_pic_address calls itself recursively to handle
         that case.  So no need to do it here.  */

      if (reg == 0)
        reg = gen_reg_rtx (Pmode);

      if (TARGET_Z10)
        {
          /* Use load relative if possible.
             lgrl <target>, sym@GOTENT  */
          new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_GOTENT);
          new_rtx = gen_rtx_CONST (Pmode, new_rtx);
          new_rtx = gen_const_mem (GET_MODE (reg), new_rtx);

          emit_move_insn (reg, new_rtx);
          new_rtx = reg;
        }
      else if (flag_pic == 1)
        {
          /* Assume GOT offset is a valid displacement operand (< 4k
             or < 512k with z990).  This is handled the same way in
             both 31- and 64-bit code (@GOT).
             lg <target>, sym@GOT(r12)  */

          if (reload_in_progress || reload_completed)
            df_set_regs_ever_live (PIC_OFFSET_TABLE_REGNUM, true);

          new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_GOT);
          new_rtx = gen_rtx_CONST (Pmode, new_rtx);
          new_rtx = gen_rtx_PLUS (Pmode, pic_offset_table_rtx, new_rtx);
          new_rtx = gen_const_mem (Pmode, new_rtx);
          emit_move_insn (reg, new_rtx);
          new_rtx = reg;
        }
      else if (TARGET_CPU_ZARCH)
        {
          /* If the GOT offset might be >= 4k, we determine the position
             of the GOT entry via a PC-relative LARL (@GOTENT).
             larl temp, sym@GOTENT
             lg   <target>, 0(temp) */

          rtx temp = reg ? reg : gen_reg_rtx (Pmode);

          gcc_assert (REGNO (temp) >= FIRST_PSEUDO_REGISTER
                      || REGNO_REG_CLASS (REGNO (temp)) == ADDR_REGS);

          new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_GOTENT);
          new_rtx = gen_rtx_CONST (Pmode, new_rtx);
          emit_move_insn (temp, new_rtx);

          new_rtx = gen_const_mem (Pmode, temp);
          emit_move_insn (reg, new_rtx);

          new_rtx = reg;
        }
      else
        {
          /* If the GOT offset might be >= 4k, we have to load it
             from the literal pool (@GOT).

             lg temp, lit-litbase(r13)
             lg <target>, 0(temp)
             lit:  .long sym@GOT  */

          rtx temp = reg ? reg : gen_reg_rtx (Pmode);

          gcc_assert (REGNO (temp) >= FIRST_PSEUDO_REGISTER
                      || REGNO_REG_CLASS (REGNO (temp)) == ADDR_REGS);

          if (reload_in_progress || reload_completed)
            df_set_regs_ever_live (PIC_OFFSET_TABLE_REGNUM, true);

          addr = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_GOT);
          addr = gen_rtx_CONST (Pmode, addr);
          addr = force_const_mem (Pmode, addr);
          emit_move_insn (temp, addr);

          new_rtx = gen_rtx_PLUS (Pmode, pic_offset_table_rtx, temp);
          new_rtx = gen_const_mem (Pmode, new_rtx);
          emit_move_insn (reg, new_rtx);
          new_rtx = reg;
        }
    }
  else if (GET_CODE (addr) == UNSPEC && GET_CODE (addend) == CONST_INT)
    {
      gcc_assert (XVECLEN (addr, 0) == 1);
      switch (XINT (addr, 1))
        {
          /* These address symbols (or PLT slots) relative to the GOT
             (not GOT slots!).  In general this will exceed the
             displacement range so these value belong into the literal
             pool.  */
        case UNSPEC_GOTOFF:
        case UNSPEC_PLTOFF:
          new_rtx = force_const_mem (Pmode, orig);
          break;

          /* For -fPIC the GOT size might exceed the displacement
             range so make sure the value is in the literal pool.  */
        case UNSPEC_GOT:
          if (flag_pic == 2)
            new_rtx = force_const_mem (Pmode, orig);
          break;

          /* For @GOTENT larl is used.  This is handled like local
             symbol refs.  */
        case UNSPEC_GOTENT:
          gcc_unreachable ();
          break;

          /* @PLT is OK as is on 64-bit, must be converted to
             GOT-relative @PLTOFF on 31-bit.  */
        case UNSPEC_PLT:
          if (!TARGET_CPU_ZARCH)
            {
              rtx temp = reg? reg : gen_reg_rtx (Pmode);

              if (reload_in_progress || reload_completed)
                df_set_regs_ever_live (PIC_OFFSET_TABLE_REGNUM, true);

              addr = XVECEXP (addr, 0, 0);
              addr = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr),
                                     UNSPEC_PLTOFF);
              if (addend != const0_rtx)
                addr = gen_rtx_PLUS (Pmode, addr, addend);
              addr = gen_rtx_CONST (Pmode, addr);
              addr = force_const_mem (Pmode, addr);
              emit_move_insn (temp, addr);

              new_rtx = gen_rtx_PLUS (Pmode, pic_offset_table_rtx, temp);
              if (reg != 0)
                {
                  s390_load_address (reg, new_rtx);
                  new_rtx = reg;
                }
            }
          else
            /* On 64 bit larl can be used.  This case is handled like
               local symbol refs.  */
            gcc_unreachable ();
          break;

          /* Everything else cannot happen.  */
        default:
          gcc_unreachable ();
        }
    }
  else if (addend != const0_rtx)
    {
      /* Otherwise, compute the sum.  */

      rtx base = legitimize_pic_address (addr, reg);
      new_rtx  = legitimize_pic_address (addend,
                                         base == reg ? NULL_RTX : reg);
      if (GET_CODE (new_rtx) == CONST_INT)
        new_rtx = plus_constant (Pmode, base, INTVAL (new_rtx));
      else
        {
          if (GET_CODE (new_rtx) == PLUS && CONSTANT_P (XEXP (new_rtx, 1)))
            {
              base = gen_rtx_PLUS (Pmode, base, XEXP (new_rtx, 0));
              new_rtx = XEXP (new_rtx, 1);
            }
          new_rtx = gen_rtx_PLUS (Pmode, base, new_rtx);
        }

      if (GET_CODE (new_rtx) == CONST)
        new_rtx = XEXP (new_rtx, 0);
      new_rtx = force_operand (new_rtx, 0);
    }

  return new_rtx;
}

/* Load the thread pointer into a register.  */

rtx
s390_get_thread_pointer (void)
{
  rtx tp = gen_reg_rtx (Pmode);

  emit_move_insn (tp, gen_rtx_REG (Pmode, TP_REGNUM));
  mark_reg_pointer (tp, BITS_PER_WORD);

  return tp;
}

/* Emit a tls call insn. The call target is the SYMBOL_REF stored
   in s390_tls_symbol which always refers to __tls_get_offset.
   The returned offset is written to RESULT_REG and an USE rtx is
   generated for TLS_CALL.  */

static GTY(()) rtx s390_tls_symbol;

static void
s390_emit_tls_call_insn (rtx result_reg, rtx tls_call)
{
  rtx insn;

  if (!flag_pic)
    emit_insn (s390_load_got ());

  if (!s390_tls_symbol)
    s390_tls_symbol = gen_rtx_SYMBOL_REF (Pmode, "__tls_get_offset");

  insn = s390_emit_call (s390_tls_symbol, tls_call, result_reg,
                         gen_rtx_REG (Pmode, RETURN_REGNUM));

  use_reg (&CALL_INSN_FUNCTION_USAGE (insn), result_reg);
  RTL_CONST_CALL_P (insn) = 1;
}

/* ADDR contains a thread-local SYMBOL_REF.  Generate code to compute
   this (thread-local) address.  REG may be used as temporary.  */

static rtx
legitimize_tls_address (rtx addr, rtx reg)
{
  rtx new_rtx, tls_call, temp, base, r2, insn;

  if (GET_CODE (addr) == SYMBOL_REF)
    switch (tls_symbolic_operand (addr))
      {
      case TLS_MODEL_GLOBAL_DYNAMIC:
        start_sequence ();
        r2 = gen_rtx_REG (Pmode, 2);
        tls_call = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_TLSGD);
        new_rtx = gen_rtx_CONST (Pmode, tls_call);
        new_rtx = force_const_mem (Pmode, new_rtx);
        emit_move_insn (r2, new_rtx);
        s390_emit_tls_call_insn (r2, tls_call);
        insn = get_insns ();
        end_sequence ();

        new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_NTPOFF);
        temp = gen_reg_rtx (Pmode);
        emit_libcall_block (insn, temp, r2, new_rtx);

        new_rtx = gen_rtx_PLUS (Pmode, s390_get_thread_pointer (), temp);
        if (reg != 0)
          {
            s390_load_address (reg, new_rtx);
            new_rtx = reg;
          }
        break;

      case TLS_MODEL_LOCAL_DYNAMIC:
        start_sequence ();
        r2 = gen_rtx_REG (Pmode, 2);
        tls_call = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, const0_rtx), UNSPEC_TLSLDM);
        new_rtx = gen_rtx_CONST (Pmode, tls_call);
        new_rtx = force_const_mem (Pmode, new_rtx);
        emit_move_insn (r2, new_rtx);
        s390_emit_tls_call_insn (r2, tls_call);
        insn = get_insns ();
        end_sequence ();

        new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, const0_rtx), UNSPEC_TLSLDM_NTPOFF);
        temp = gen_reg_rtx (Pmode);
        emit_libcall_block (insn, temp, r2, new_rtx);

        new_rtx = gen_rtx_PLUS (Pmode, s390_get_thread_pointer (), temp);
        base = gen_reg_rtx (Pmode);
        s390_load_address (base, new_rtx);

        new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_DTPOFF);
        new_rtx = gen_rtx_CONST (Pmode, new_rtx);
        new_rtx = force_const_mem (Pmode, new_rtx);
        temp = gen_reg_rtx (Pmode);
        emit_move_insn (temp, new_rtx);

        new_rtx = gen_rtx_PLUS (Pmode, base, temp);
        if (reg != 0)
          {
            s390_load_address (reg, new_rtx);
            new_rtx = reg;
          }
        break;

      case TLS_MODEL_INITIAL_EXEC:
        if (flag_pic == 1)
          {
            /* Assume GOT offset < 4k.  This is handled the same way
               in both 31- and 64-bit code.  */

            if (reload_in_progress || reload_completed)
              df_set_regs_ever_live (PIC_OFFSET_TABLE_REGNUM, true);

            new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_GOTNTPOFF);
            new_rtx = gen_rtx_CONST (Pmode, new_rtx);
            new_rtx = gen_rtx_PLUS (Pmode, pic_offset_table_rtx, new_rtx);
            new_rtx = gen_const_mem (Pmode, new_rtx);
            temp = gen_reg_rtx (Pmode);
            emit_move_insn (temp, new_rtx);
          }
        else if (TARGET_CPU_ZARCH)
          {
            /* If the GOT offset might be >= 4k, we determine the position
               of the GOT entry via a PC-relative LARL.  */

            new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_INDNTPOFF);
            new_rtx = gen_rtx_CONST (Pmode, new_rtx);
            temp = gen_reg_rtx (Pmode);
            emit_move_insn (temp, new_rtx);

            new_rtx = gen_const_mem (Pmode, temp);
            temp = gen_reg_rtx (Pmode);
            emit_move_insn (temp, new_rtx);
          }
        else if (flag_pic)
          {
            /* If the GOT offset might be >= 4k, we have to load it
               from the literal pool.  */

            if (reload_in_progress || reload_completed)
              df_set_regs_ever_live (PIC_OFFSET_TABLE_REGNUM, true);

            new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_GOTNTPOFF);
            new_rtx = gen_rtx_CONST (Pmode, new_rtx);
            new_rtx = force_const_mem (Pmode, new_rtx);
            temp = gen_reg_rtx (Pmode);
            emit_move_insn (temp, new_rtx);

            new_rtx = gen_rtx_PLUS (Pmode, pic_offset_table_rtx, temp);
            new_rtx = gen_const_mem (Pmode, new_rtx);

            new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (2, new_rtx, addr), UNSPEC_TLS_LOAD);
            temp = gen_reg_rtx (Pmode);
            emit_insn (gen_rtx_SET (Pmode, temp, new_rtx));
          }
        else
          {
            /* In position-dependent code, load the absolute address of
               the GOT entry from the literal pool.  */

            new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_INDNTPOFF);
            new_rtx = gen_rtx_CONST (Pmode, new_rtx);
            new_rtx = force_const_mem (Pmode, new_rtx);
            temp = gen_reg_rtx (Pmode);
            emit_move_insn (temp, new_rtx);

            new_rtx = temp;
            new_rtx = gen_const_mem (Pmode, new_rtx);
            new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (2, new_rtx, addr), UNSPEC_TLS_LOAD);
            temp = gen_reg_rtx (Pmode);
            emit_insn (gen_rtx_SET (Pmode, temp, new_rtx));
          }

        new_rtx = gen_rtx_PLUS (Pmode, s390_get_thread_pointer (), temp);
        if (reg != 0)
          {
            s390_load_address (reg, new_rtx);
            new_rtx = reg;
          }
        break;

      case TLS_MODEL_LOCAL_EXEC:
        new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_NTPOFF);
        new_rtx = gen_rtx_CONST (Pmode, new_rtx);
        new_rtx = force_const_mem (Pmode, new_rtx);
        temp = gen_reg_rtx (Pmode);
        emit_move_insn (temp, new_rtx);

        new_rtx = gen_rtx_PLUS (Pmode, s390_get_thread_pointer (), temp);
        if (reg != 0)
          {
            s390_load_address (reg, new_rtx);
            new_rtx = reg;
          }
        break;

      default:
        gcc_unreachable ();
      }

  else if (GET_CODE (addr) == CONST && GET_CODE (XEXP (addr, 0)) == UNSPEC)
    {
      switch (XINT (XEXP (addr, 0), 1))
        {
        case UNSPEC_INDNTPOFF:
          gcc_assert (TARGET_CPU_ZARCH);
          new_rtx = addr;
          break;

        default:
          gcc_unreachable ();
        }
    }

  else if (GET_CODE (addr) == CONST && GET_CODE (XEXP (addr, 0)) == PLUS
           && GET_CODE (XEXP (XEXP (addr, 0), 1)) == CONST_INT)
    {
      new_rtx = XEXP (XEXP (addr, 0), 0);
      if (GET_CODE (new_rtx) != SYMBOL_REF)
        new_rtx = gen_rtx_CONST (Pmode, new_rtx);

      new_rtx = legitimize_tls_address (new_rtx, reg);
      new_rtx = plus_constant (Pmode, new_rtx,
                               INTVAL (XEXP (XEXP (addr, 0), 1)));
      new_rtx = force_operand (new_rtx, 0);
    }

  else
    gcc_unreachable ();  /* for now ... */

  return new_rtx;
}

/* Emit insns making the address in operands[1] valid for a standard
   move to operands[0].  operands[1] is replaced by an address which
   should be used instead of the former RTX to emit the move
   pattern.  */

void
emit_symbolic_move (rtx *operands)
{
  rtx temp = !can_create_pseudo_p () ? operands[0] : gen_reg_rtx (Pmode);

  if (GET_CODE (operands[0]) == MEM)
    operands[1] = force_reg (Pmode, operands[1]);
  else if (TLS_SYMBOLIC_CONST (operands[1]))
    operands[1] = legitimize_tls_address (operands[1], temp);
  else if (flag_pic)
    operands[1] = legitimize_pic_address (operands[1], temp);
}

/* Try machine-dependent ways of modifying an illegitimate address X
   to be legitimate.  If we find one, return the new, valid address.

   OLDX is the address as it was before break_out_memory_refs was called.
   In some cases it is useful to look at this to decide what needs to be done.

   MODE is the mode of the operand pointed to by X.

   When -fpic is used, special handling is needed for symbolic references.
   See comments by legitimize_pic_address for details.  */

static rtx
s390_legitimize_address (rtx x, rtx oldx ATTRIBUTE_UNUSED,
                         machine_mode mode ATTRIBUTE_UNUSED)
{
  rtx constant_term = const0_rtx;

  if (TLS_SYMBOLIC_CONST (x))
    {
      x = legitimize_tls_address (x, 0);

      if (s390_legitimate_address_p (mode, x, FALSE))
        return x;
    }
  else if (GET_CODE (x) == PLUS
           && (TLS_SYMBOLIC_CONST (XEXP (x, 0))
               || TLS_SYMBOLIC_CONST (XEXP (x, 1))))
    {
      return x;
    }
  else if (flag_pic)
    {
      if (SYMBOLIC_CONST (x)
          || (GET_CODE (x) == PLUS
              && (SYMBOLIC_CONST (XEXP (x, 0))
                  || SYMBOLIC_CONST (XEXP (x, 1)))))
          x = legitimize_pic_address (x, 0);

      if (s390_legitimate_address_p (mode, x, FALSE))
        return x;
    }

  x = eliminate_constant_term (x, &constant_term);

  /* Optimize loading of large displacements by splitting them
     into the multiple of 4K and the rest; this allows the
     former to be CSE'd if possible.

     Don't do this if the displacement is added to a register
     pointing into the stack frame, as the offsets will
     change later anyway.  */

  if (GET_CODE (constant_term) == CONST_INT
      && !TARGET_LONG_DISPLACEMENT
      && !DISP_IN_RANGE (INTVAL (constant_term))
      && !(REG_P (x) && REGNO_PTR_FRAME_P (REGNO (x))))
    {
      HOST_WIDE_INT lower = INTVAL (constant_term) & 0xfff;
      HOST_WIDE_INT upper = INTVAL (constant_term) ^ lower;

      rtx temp = gen_reg_rtx (Pmode);
      rtx val  = force_operand (GEN_INT (upper), temp);
      if (val != temp)
        emit_move_insn (temp, val);

      x = gen_rtx_PLUS (Pmode, x, temp);
      constant_term = GEN_INT (lower);
    }

  if (GET_CODE (x) == PLUS)
    {
      if (GET_CODE (XEXP (x, 0)) == REG)
        {
          rtx temp = gen_reg_rtx (Pmode);
          rtx val  = force_operand (XEXP (x, 1), temp);
          if (val != temp)
            emit_move_insn (temp, val);

          x = gen_rtx_PLUS (Pmode, XEXP (x, 0), temp);
        }

      else if (GET_CODE (XEXP (x, 1)) == REG)
        {
          rtx temp = gen_reg_rtx (Pmode);
          rtx val  = force_operand (XEXP (x, 0), temp);
          if (val != temp)
            emit_move_insn (temp, val);

          x = gen_rtx_PLUS (Pmode, temp, XEXP (x, 1));
        }
    }

  if (constant_term != const0_rtx)
    x = gen_rtx_PLUS (Pmode, x, constant_term);

  return x;
}

/* Try a machine-dependent way of reloading an illegitimate address AD
   operand.  If we find one, push the reload and return the new address.

   MODE is the mode of the enclosing MEM.  OPNUM is the operand number
   and TYPE is the reload type of the current reload.  */

rtx
legitimize_reload_address (rtx ad, machine_mode mode ATTRIBUTE_UNUSED,
                           int opnum, int type)
{
  if (!optimize || TARGET_LONG_DISPLACEMENT)
    return NULL_RTX;

  if (GET_CODE (ad) == PLUS)
    {
      rtx tem = simplify_binary_operation (PLUS, Pmode,
                                           XEXP (ad, 0), XEXP (ad, 1));
      if (tem)
        ad = tem;
    }

  if (GET_CODE (ad) == PLUS
      && GET_CODE (XEXP (ad, 0)) == REG
      && GET_CODE (XEXP (ad, 1)) == CONST_INT
      && !DISP_IN_RANGE (INTVAL (XEXP (ad, 1))))
    {
      HOST_WIDE_INT lower = INTVAL (XEXP (ad, 1)) & 0xfff;
      HOST_WIDE_INT upper = INTVAL (XEXP (ad, 1)) ^ lower;
      rtx cst, tem, new_rtx;

      cst = GEN_INT (upper);
      if (!legitimate_reload_constant_p (cst))
        cst = force_const_mem (Pmode, cst);

      tem = gen_rtx_PLUS (Pmode, XEXP (ad, 0), cst);
      new_rtx = gen_rtx_PLUS (Pmode, tem, GEN_INT (lower));

      push_reload (XEXP (tem, 1), 0, &XEXP (tem, 1), 0,
                   BASE_REG_CLASS, Pmode, VOIDmode, 0, 0,
                   opnum, (enum reload_type) type);
      return new_rtx;
    }

  return NULL_RTX;
}

/* Emit code to move LEN bytes from DST to SRC.  */

bool
s390_expand_movmem (rtx dst, rtx src, rtx len)
{
  /* When tuning for z10 or higher we rely on the Glibc functions to
     do the right thing. Only for constant lengths below 64k we will
     generate inline code.  */
  if (s390_tune >= PROCESSOR_2097_Z10
      && (GET_CODE (len) != CONST_INT || INTVAL (len) > (1<<16)))
    return false;

  if (GET_CODE (len) == CONST_INT && INTVAL (len) >= 0 && INTVAL (len) <= 256)
    {
      if (INTVAL (len) > 0)
        emit_insn (gen_movmem_short (dst, src, GEN_INT (INTVAL (len) - 1)));
    }

  else if (TARGET_MVCLE)
    {
      emit_insn (gen_movmem_long (dst, src, convert_to_mode (Pmode, len, 1)));
    }

  else
    {
      rtx dst_addr, src_addr, count, blocks, temp;
      rtx_code_label *loop_start_label = gen_label_rtx ();
      rtx_code_label *loop_end_label = gen_label_rtx ();
      rtx_code_label *end_label = gen_label_rtx ();
      machine_mode mode;

      mode = GET_MODE (len);
      if (mode == VOIDmode)
        mode = Pmode;

      dst_addr = gen_reg_rtx (Pmode);
      src_addr = gen_reg_rtx (Pmode);
      count = gen_reg_rtx (mode);
      blocks = gen_reg_rtx (mode);

      convert_move (count, len, 1);
      emit_cmp_and_jump_insns (count, const0_rtx,
                               EQ, NULL_RTX, mode, 1, end_label);

      emit_move_insn (dst_addr, force_operand (XEXP (dst, 0), NULL_RTX));
      emit_move_insn (src_addr, force_operand (XEXP (src, 0), NULL_RTX));
      dst = change_address (dst, VOIDmode, dst_addr);
      src = change_address (src, VOIDmode, src_addr);

      temp = expand_binop (mode, add_optab, count, constm1_rtx, count, 1,
                           OPTAB_DIRECT);
      if (temp != count)
        emit_move_insn (count, temp);

      temp = expand_binop (mode, lshr_optab, count, GEN_INT (8), blocks, 1,
                           OPTAB_DIRECT);
      if (temp != blocks)
        emit_move_insn (blocks, temp);

      emit_cmp_and_jump_insns (blocks, const0_rtx,
                               EQ, NULL_RTX, mode, 1, loop_end_label);

      emit_label (loop_start_label);

      if (TARGET_Z10
          && (GET_CODE (len) != CONST_INT || INTVAL (len) > 768))
        {
          rtx prefetch;

          /* Issue a read prefetch for the +3 cache line.  */
          prefetch = gen_prefetch (gen_rtx_PLUS (Pmode, src_addr, GEN_INT (768)),
                                   const0_rtx, const0_rtx);
          PREFETCH_SCHEDULE_BARRIER_P (prefetch) = true;
          emit_insn (prefetch);

          /* Issue a write prefetch for the +3 cache line.  */
          prefetch = gen_prefetch (gen_rtx_PLUS (Pmode, dst_addr, GEN_INT (768)),
                                   const1_rtx, const0_rtx);
          PREFETCH_SCHEDULE_BARRIER_P (prefetch) = true;
          emit_insn (prefetch);
        }

      emit_insn (gen_movmem_short (dst, src, GEN_INT (255)));
      s390_load_address (dst_addr,
                         gen_rtx_PLUS (Pmode, dst_addr, GEN_INT (256)));
      s390_load_address (src_addr,
                         gen_rtx_PLUS (Pmode, src_addr, GEN_INT (256)));

      temp = expand_binop (mode, add_optab, blocks, constm1_rtx, blocks, 1,
                           OPTAB_DIRECT);
      if (temp != blocks)
        emit_move_insn (blocks, temp);

      emit_cmp_and_jump_insns (blocks, const0_rtx,
                               EQ, NULL_RTX, mode, 1, loop_end_label);

      emit_jump (loop_start_label);
      emit_label (loop_end_label);

      emit_insn (gen_movmem_short (dst, src,
                                   convert_to_mode (Pmode, count, 1)));
      emit_label (end_label);
    }
  return true;
}

/* Emit code to set LEN bytes at DST to VAL.
   Make use of clrmem if VAL is zero.  */

void
s390_expand_setmem (rtx dst, rtx len, rtx val)
{
  if (GET_CODE (len) == CONST_INT && INTVAL (len) == 0)
    return;

  gcc_assert (GET_CODE (val) == CONST_INT || GET_MODE (val) == QImode);

  if (GET_CODE (len) == CONST_INT && INTVAL (len) > 0 && INTVAL (len) <= 257)
    {
      if (val == const0_rtx && INTVAL (len) <= 256)
        emit_insn (gen_clrmem_short (dst, GEN_INT (INTVAL (len) - 1)));
      else
        {
          /* Initialize memory by storing the first byte.  */
          emit_move_insn (adjust_address (dst, QImode, 0), val);

          if (INTVAL (len) > 1)
            {
              /* Initiate 1 byte overlap move.
                 The first byte of DST is propagated through DSTP1.
                 Prepare a movmem for:  DST+1 = DST (length = LEN - 1).
                 DST is set to size 1 so the rest of the memory location
                 does not count as source operand.  */
              rtx dstp1 = adjust_address (dst, VOIDmode, 1);
              set_mem_size (dst, 1);

              emit_insn (gen_movmem_short (dstp1, dst,
                                           GEN_INT (INTVAL (len) - 2)));
            }
        }
    }

  else if (TARGET_MVCLE)
    {
      val = force_not_mem (convert_modes (Pmode, QImode, val, 1));
      emit_insn (gen_setmem_long (dst, convert_to_mode (Pmode, len, 1), val));
    }

  else
    {
      rtx dst_addr, count, blocks, temp, dstp1 = NULL_RTX;
      rtx_code_label *loop_start_label = gen_label_rtx ();
      rtx_code_label *loop_end_label = gen_label_rtx ();
      rtx_code_label *end_label = gen_label_rtx ();
      machine_mode mode;

      mode = GET_MODE (len);
      if (mode == VOIDmode)
        mode = Pmode;

      dst_addr = gen_reg_rtx (Pmode);
      count = gen_reg_rtx (mode);
      blocks = gen_reg_rtx (mode);

      convert_move (count, len, 1);
      emit_cmp_and_jump_insns (count, const0_rtx,
                               EQ, NULL_RTX, mode, 1, end_label);

      emit_move_insn (dst_addr, force_operand (XEXP (dst, 0), NULL_RTX));
      dst = change_address (dst, VOIDmode, dst_addr);

      if (val == const0_rtx)
        temp = expand_binop (mode, add_optab, count, constm1_rtx, count, 1,
                             OPTAB_DIRECT);
      else
        {
          dstp1 = adjust_address (dst, VOIDmode, 1);
          set_mem_size (dst, 1);

          /* Initialize memory by storing the first byte.  */
          emit_move_insn (adjust_address (dst, QImode, 0), val);

          /* If count is 1 we are done.  */
          emit_cmp_and_jump_insns (count, const1_rtx,
                                   EQ, NULL_RTX, mode, 1, end_label);

          temp = expand_binop (mode, add_optab, count, GEN_INT (-2), count, 1,
                               OPTAB_DIRECT);
        }
      if (temp != count)
        emit_move_insn (count, temp);

      temp = expand_binop (mode, lshr_optab, count, GEN_INT (8), blocks, 1,
                           OPTAB_DIRECT);
      if (temp != blocks)
        emit_move_insn (blocks, temp);

      emit_cmp_and_jump_insns (blocks, const0_rtx,
                               EQ, NULL_RTX, mode, 1, loop_end_label);

      emit_label (loop_start_label);

      if (TARGET_Z10
          && (GET_CODE (len) != CONST_INT || INTVAL (len) > 1024))
        {
          /* Issue a write prefetch for the +4 cache line.  */
          rtx prefetch = gen_prefetch (gen_rtx_PLUS (Pmode, dst_addr,
                                                     GEN_INT (1024)),
                                       const1_rtx, const0_rtx);
          emit_insn (prefetch);
          PREFETCH_SCHEDULE_BARRIER_P (prefetch) = true;
        }

      if (val == const0_rtx)
        emit_insn (gen_clrmem_short (dst, GEN_INT (255)));
      else
        emit_insn (gen_movmem_short (dstp1, dst, GEN_INT (255)));
      s390_load_address (dst_addr,
                         gen_rtx_PLUS (Pmode, dst_addr, GEN_INT (256)));

      temp = expand_binop (mode, add_optab, blocks, constm1_rtx, blocks, 1,
                           OPTAB_DIRECT);
      if (temp != blocks)
        emit_move_insn (blocks, temp);

      emit_cmp_and_jump_insns (blocks, const0_rtx,
                               EQ, NULL_RTX, mode, 1, loop_end_label);

      emit_jump (loop_start_label);
      emit_label (loop_end_label);

      if (val == const0_rtx)
        emit_insn (gen_clrmem_short (dst, convert_to_mode (Pmode, count, 1)));
      else
        emit_insn (gen_movmem_short (dstp1, dst, convert_to_mode (Pmode, count, 1)));
      emit_label (end_label);
    }
}

/* Emit code to compare LEN bytes at OP0 with those at OP1,
   and return the result in TARGET.  */

bool
s390_expand_cmpmem (rtx target, rtx op0, rtx op1, rtx len)
{
  rtx ccreg = gen_rtx_REG (CCUmode, CC_REGNUM);
  rtx tmp;

  /* When tuning for z10 or higher we rely on the Glibc functions to
     do the right thing. Only for constant lengths below 64k we will
     generate inline code.  */
  if (s390_tune >= PROCESSOR_2097_Z10
      && (GET_CODE (len) != CONST_INT || INTVAL (len) > (1<<16)))
    return false;

  /* As the result of CMPINT is inverted compared to what we need,
     we have to swap the operands.  */
  tmp = op0; op0 = op1; op1 = tmp;

  if (GET_CODE (len) == CONST_INT && INTVAL (len) >= 0 && INTVAL (len) <= 256)
    {
      if (INTVAL (len) > 0)
        {
          emit_insn (gen_cmpmem_short (op0, op1, GEN_INT (INTVAL (len) - 1)));
          emit_insn (gen_cmpint (target, ccreg));
        }
      else
        emit_move_insn (target, const0_rtx);
    }
  else if (TARGET_MVCLE)
    {
      emit_insn (gen_cmpmem_long (op0, op1, convert_to_mode (Pmode, len, 1)));
      emit_insn (gen_cmpint (target, ccreg));
    }
  else
    {
      rtx addr0, addr1, count, blocks, temp;
      rtx_code_label *loop_start_label = gen_label_rtx ();
      rtx_code_label *loop_end_label = gen_label_rtx ();
      rtx_code_label *end_label = gen_label_rtx ();
      machine_mode mode;

      mode = GET_MODE (len);
      if (mode == VOIDmode)
        mode = Pmode;

      addr0 = gen_reg_rtx (Pmode);
      addr1 = gen_reg_rtx (Pmode);
      count = gen_reg_rtx (mode);
      blocks = gen_reg_rtx (mode);

      convert_move (count, len, 1);
      emit_cmp_and_jump_insns (count, const0_rtx,
                               EQ, NULL_RTX, mode, 1, end_label);

      emit_move_insn (addr0, force_operand (XEXP (op0, 0), NULL_RTX));
      emit_move_insn (addr1, force_operand (XEXP (op1, 0), NULL_RTX));
      op0 = change_address (op0, VOIDmode, addr0);
      op1 = change_address (op1, VOIDmode, addr1);

      temp = expand_binop (mode, add_optab, count, constm1_rtx, count, 1,
                           OPTAB_DIRECT);
      if (temp != count)
        emit_move_insn (count, temp);

      temp = expand_binop (mode, lshr_optab, count, GEN_INT (8), blocks, 1,
                           OPTAB_DIRECT);
      if (temp != blocks)
        emit_move_insn (blocks, temp);

      emit_cmp_and_jump_insns (blocks, const0_rtx,
                               EQ, NULL_RTX, mode, 1, loop_end_label);

      emit_label (loop_start_label);

      if (TARGET_Z10
          && (GET_CODE (len) != CONST_INT || INTVAL (len) > 512))
        {
          rtx prefetch;

          /* Issue a read prefetch for the +2 cache line of operand 1.  */
          prefetch = gen_prefetch (gen_rtx_PLUS (Pmode, addr0, GEN_INT (512)),
                                   const0_rtx, const0_rtx);
          emit_insn (prefetch);
          PREFETCH_SCHEDULE_BARRIER_P (prefetch) = true;

          /* Issue a read prefetch for the +2 cache line of operand 2.  */
          prefetch = gen_prefetch (gen_rtx_PLUS (Pmode, addr1, GEN_INT (512)),
                                   const0_rtx, const0_rtx);
          emit_insn (prefetch);
          PREFETCH_SCHEDULE_BARRIER_P (prefetch) = true;
        }

      emit_insn (gen_cmpmem_short (op0, op1, GEN_INT (255)));
      temp = gen_rtx_NE (VOIDmode, ccreg, const0_rtx);
      temp = gen_rtx_IF_THEN_ELSE (VOIDmode, temp,
                        gen_rtx_LABEL_REF (VOIDmode, end_label), pc_rtx);
      temp = gen_rtx_SET (VOIDmode, pc_rtx, temp);
      emit_jump_insn (temp);

      s390_load_address (addr0,
                         gen_rtx_PLUS (Pmode, addr0, GEN_INT (256)));
      s390_load_address (addr1,
                         gen_rtx_PLUS (Pmode, addr1, GEN_INT (256)));

      temp = expand_binop (mode, add_optab, blocks, constm1_rtx, blocks, 1,
                           OPTAB_DIRECT);
      if (temp != blocks)
        emit_move_insn (blocks, temp);

      emit_cmp_and_jump_insns (blocks, const0_rtx,
                               EQ, NULL_RTX, mode, 1, loop_end_label);

      emit_jump (loop_start_label);
      emit_label (loop_end_label);

      emit_insn (gen_cmpmem_short (op0, op1,
                                   convert_to_mode (Pmode, count, 1)));
      emit_label (end_label);

      emit_insn (gen_cmpint (target, ccreg));
    }
  return true;
}


/* Expand conditional increment or decrement using alc/slb instructions.
   Should generate code setting DST to either SRC or SRC + INCREMENT,
   depending on the result of the comparison CMP_OP0 CMP_CODE CMP_OP1.
   Returns true if successful, false otherwise.

   That makes it possible to implement some if-constructs without jumps e.g.:
   (borrow = CC0 | CC1 and carry = CC2 | CC3)
   unsigned int a, b, c;
   if (a < b)  c++; -> CCU  b > a  -> CC2;    c += carry;
   if (a < b)  c--; -> CCL3 a - b  -> borrow; c -= borrow;
   if (a <= b) c++; -> CCL3 b - a  -> borrow; c += carry;
   if (a <= b) c--; -> CCU  a <= b -> borrow; c -= borrow;

   Checks for EQ and NE with a nonzero value need an additional xor e.g.:
   if (a == b) c++; -> CCL3 a ^= b; 0 - a  -> borrow;    c += carry;
   if (a == b) c--; -> CCU  a ^= b; a <= 0 -> CC0 | CC1; c -= borrow;
   if (a != b) c++; -> CCU  a ^= b; a > 0  -> CC2;       c += carry;
   if (a != b) c--; -> CCL3 a ^= b; 0 - a  -> borrow;    c -= borrow; */

bool
s390_expand_addcc (enum rtx_code cmp_code, rtx cmp_op0, rtx cmp_op1,
                   rtx dst, rtx src, rtx increment)
{
  machine_mode cmp_mode;
  machine_mode cc_mode;
  rtx op_res;
  rtx insn;
  rtvec p;
  int ret;

  if ((GET_MODE (cmp_op0) == SImode || GET_MODE (cmp_op0) == VOIDmode)
      && (GET_MODE (cmp_op1) == SImode || GET_MODE (cmp_op1) == VOIDmode))
    cmp_mode = SImode;
  else if ((GET_MODE (cmp_op0) == DImode || GET_MODE (cmp_op0) == VOIDmode)
           && (GET_MODE (cmp_op1) == DImode || GET_MODE (cmp_op1) == VOIDmode))
    cmp_mode = DImode;
  else
    return false;

  /* Try ADD LOGICAL WITH CARRY.  */
  if (increment == const1_rtx)
    {
      /* Determine CC mode to use.  */
      if (cmp_code == EQ || cmp_code == NE)
        {
          if (cmp_op1 != const0_rtx)
            {
              cmp_op0 = expand_simple_binop (cmp_mode, XOR, cmp_op0, cmp_op1,
                                             NULL_RTX, 0, OPTAB_WIDEN);
              cmp_op1 = const0_rtx;
            }

          cmp_code = cmp_code == EQ ? LEU : GTU;
        }

      if (cmp_code == LTU || cmp_code == LEU)
        {
          rtx tem = cmp_op0;
          cmp_op0 = cmp_op1;
          cmp_op1 = tem;
          cmp_code = swap_condition (cmp_code);
        }

      switch (cmp_code)
        {
          case GTU:
            cc_mode = CCUmode;
            break;

          case GEU:
            cc_mode = CCL3mode;
            break;

          default:
            return false;
        }

      /* Emit comparison instruction pattern. */
      if (!register_operand (cmp_op0, cmp_mode))
        cmp_op0 = force_reg (cmp_mode, cmp_op0);

      insn = gen_rtx_SET (VOIDmode, gen_rtx_REG (cc_mode, CC_REGNUM),
                          gen_rtx_COMPARE (cc_mode, cmp_op0, cmp_op1));
      /* We use insn_invalid_p here to add clobbers if required.  */
      ret = insn_invalid_p (emit_insn (insn), false);
      gcc_assert (!ret);

      /* Emit ALC instruction pattern.  */
      op_res = gen_rtx_fmt_ee (cmp_code, GET_MODE (dst),
                               gen_rtx_REG (cc_mode, CC_REGNUM),
                               const0_rtx);

      if (src != const0_rtx)
        {
          if (!register_operand (src, GET_MODE (dst)))
            src = force_reg (GET_MODE (dst), src);

          op_res = gen_rtx_PLUS (GET_MODE (dst), op_res, src);
          op_res = gen_rtx_PLUS (GET_MODE (dst), op_res, const0_rtx);
        }

      p = rtvec_alloc (2);
      RTVEC_ELT (p, 0) =
        gen_rtx_SET (VOIDmode, dst, op_res);
      RTVEC_ELT (p, 1) =
        gen_rtx_CLOBBER (VOIDmode, gen_rtx_REG (CCmode, CC_REGNUM));
      emit_insn (gen_rtx_PARALLEL (VOIDmode, p));

      return true;
    }

  /* Try SUBTRACT LOGICAL WITH BORROW.  */
  if (increment == constm1_rtx)
    {
      /* Determine CC mode to use.  */
      if (cmp_code == EQ || cmp_code == NE)
        {
          if (cmp_op1 != const0_rtx)
            {
              cmp_op0 = expand_simple_binop (cmp_mode, XOR, cmp_op0, cmp_op1,
                                             NULL_RTX, 0, OPTAB_WIDEN);
              cmp_op1 = const0_rtx;
            }

          cmp_code = cmp_code == EQ ? LEU : GTU;
        }

      if (cmp_code == GTU || cmp_code == GEU)
        {
          rtx tem = cmp_op0;
          cmp_op0 = cmp_op1;
          cmp_op1 = tem;
          cmp_code = swap_condition (cmp_code);
        }

      switch (cmp_code)
        {
          case LEU:
            cc_mode = CCUmode;
            break;

          case LTU:
            cc_mode = CCL3mode;
            break;

          default:
            return false;
        }

      /* Emit comparison instruction pattern. */
      if (!register_operand (cmp_op0, cmp_mode))
        cmp_op0 = force_reg (cmp_mode, cmp_op0);

      insn = gen_rtx_SET (VOIDmode, gen_rtx_REG (cc_mode, CC_REGNUM),
                          gen_rtx_COMPARE (cc_mode, cmp_op0, cmp_op1));
      /* We use insn_invalid_p here to add clobbers if required.  */
      ret = insn_invalid_p (emit_insn (insn), false);
      gcc_assert (!ret);

      /* Emit SLB instruction pattern.  */
      if (!register_operand (src, GET_MODE (dst)))
        src = force_reg (GET_MODE (dst), src);

      op_res = gen_rtx_MINUS (GET_MODE (dst),
                              gen_rtx_MINUS (GET_MODE (dst), src, const0_rtx),
                              gen_rtx_fmt_ee (cmp_code, GET_MODE (dst),
                                              gen_rtx_REG (cc_mode, CC_REGNUM),
                                              const0_rtx));
      p = rtvec_alloc (2);
      RTVEC_ELT (p, 0) =
        gen_rtx_SET (VOIDmode, dst, op_res);
      RTVEC_ELT (p, 1) =
        gen_rtx_CLOBBER (VOIDmode, gen_rtx_REG (CCmode, CC_REGNUM));
      emit_insn (gen_rtx_PARALLEL (VOIDmode, p));

      return true;
    }

  return false;
}

/* Expand code for the insv template. Return true if successful.  */

bool
s390_expand_insv (rtx dest, rtx op1, rtx op2, rtx src)
{
  int bitsize = INTVAL (op1);
  int bitpos = INTVAL (op2);
  machine_mode mode = GET_MODE (dest);
  machine_mode smode;
  int smode_bsize, mode_bsize;
  rtx op, clobber;

  if (bitsize + bitpos > GET_MODE_BITSIZE (mode))
    return false;

  /* Generate INSERT IMMEDIATE (IILL et al).  */
  /* (set (ze (reg)) (const_int)).  */
  if (TARGET_ZARCH
      && register_operand (dest, word_mode)
      && (bitpos % 16) == 0
      && (bitsize % 16) == 0
      && const_int_operand (src, VOIDmode))
    {
      HOST_WIDE_INT val = INTVAL (src);
      int regpos = bitpos + bitsize;

      while (regpos > bitpos)
        {
          machine_mode putmode;
          int putsize;

          if (TARGET_EXTIMM && (regpos % 32 == 0) && (regpos >= bitpos + 32))
            putmode = SImode;
          else
            putmode = HImode;

          putsize = GET_MODE_BITSIZE (putmode);
          regpos -= putsize;
          emit_move_insn (gen_rtx_ZERO_EXTRACT (word_mode, dest,
                                                GEN_INT (putsize),
                                                GEN_INT (regpos)),
                          gen_int_mode (val, putmode));
          val >>= putsize;
        }
      gcc_assert (regpos == bitpos);
      return true;
    }

  smode = smallest_mode_for_size (bitsize, MODE_INT);
  smode_bsize = GET_MODE_BITSIZE (smode);
  mode_bsize = GET_MODE_BITSIZE (mode);

  /* Generate STORE CHARACTERS UNDER MASK (STCM et al).  */
  if (bitpos == 0
      && (bitsize % BITS_PER_UNIT) == 0
      && MEM_P (dest)
      && (register_operand (src, word_mode)
          || const_int_operand (src, VOIDmode)))
    {
      /* Emit standard pattern if possible.  */
      if (smode_bsize == bitsize)
        {
          emit_move_insn (adjust_address (dest, smode, 0),
                          gen_lowpart (smode, src));
          return true;
        }

      /* (set (ze (mem)) (const_int)).  */
      else if (const_int_operand (src, VOIDmode))
        {
          int size = bitsize / BITS_PER_UNIT;
          rtx src_mem = adjust_address (force_const_mem (word_mode, src),
                                        BLKmode,
                                        UNITS_PER_WORD - size);

          dest = adjust_address (dest, BLKmode, 0);
          set_mem_size (dest, size);
          s390_expand_movmem (dest, src_mem, GEN_INT (size));
          return true;
        }

      /* (set (ze (mem)) (reg)).  */
      else if (register_operand (src, word_mode))
        {
          if (bitsize <= 32)
            emit_move_insn (gen_rtx_ZERO_EXTRACT (word_mode, dest, op1,
                                                  const0_rtx), src);
          else
            {
              /* Emit st,stcmh sequence.  */
              int stcmh_width = bitsize - 32;
              int size = stcmh_width / BITS_PER_UNIT;

              emit_move_insn (adjust_address (dest, SImode, size),
                              gen_lowpart (SImode, src));
              set_mem_size (dest, size);
              emit_move_insn (gen_rtx_ZERO_EXTRACT (word_mode, dest,
                                                    GEN_INT (stcmh_width),
                                                    const0_rtx),
                              gen_rtx_LSHIFTRT (word_mode, src, GEN_INT (32)));
            }
          return true;
        }
    }

  /* Generate INSERT CHARACTERS UNDER MASK (IC, ICM et al).  */
  if ((bitpos % BITS_PER_UNIT) == 0
      && (bitsize % BITS_PER_UNIT) == 0
      && (bitpos & 32) == ((bitpos + bitsize - 1) & 32)
      && MEM_P (src)
      && (mode == DImode || mode == SImode)
      && register_operand (dest, mode))
    {
      /* Emit a strict_low_part pattern if possible.  */
      if (smode_bsize == bitsize && bitpos == mode_bsize - smode_bsize)
        {
          op = gen_rtx_STRICT_LOW_PART (VOIDmode, gen_lowpart (smode, dest));
          op = gen_rtx_SET (VOIDmode, op, gen_lowpart (smode, src));
          clobber = gen_rtx_CLOBBER (VOIDmode, gen_rtx_REG (CCmode, CC_REGNUM));
          emit_insn (gen_rtx_PARALLEL (VOIDmode, gen_rtvec (2, op, clobber)));
          return true;
        }

      /* ??? There are more powerful versions of ICM that are not
         completely represented in the md file.  */
    }

  /* For z10, generate ROTATE THEN INSERT SELECTED BITS (RISBG et al).  */
  if (TARGET_Z10 && (mode == DImode || mode == SImode))
    {
      machine_mode mode_s = GET_MODE (src);

      if (mode_s == VOIDmode)
        {
          /* Assume const_int etc already in the proper mode.  */
          src = force_reg (mode, src);
        }
      else if (mode_s != mode)
        {
          gcc_assert (GET_MODE_BITSIZE (mode_s) >= bitsize);
          src = force_reg (mode_s, src);
          src = gen_lowpart (mode, src);
        }

      op = gen_rtx_ZERO_EXTRACT (mode, dest, op1, op2),
      op = gen_rtx_SET (VOIDmode, op, src);

      if (!TARGET_ZEC12)
        {
          clobber = gen_rtx_CLOBBER (VOIDmode, gen_rtx_REG (CCmode, CC_REGNUM));
          op = gen_rtx_PARALLEL (VOIDmode, gen_rtvec (2, op, clobber));
        }
      emit_insn (op);

      return true;
    }

  return false;
}

/* A subroutine of s390_expand_cs_hqi and s390_expand_atomic which returns a
   register that holds VAL of mode MODE shifted by COUNT bits.  */

static inline rtx
s390_expand_mask_and_shift (rtx val, machine_mode mode, rtx count)
{
  val = expand_simple_binop (SImode, AND, val, GEN_INT (GET_MODE_MASK (mode)),
                             NULL_RTX, 1, OPTAB_DIRECT);
  return expand_simple_binop (SImode, ASHIFT, val, count,
                              NULL_RTX, 1, OPTAB_DIRECT);
}

/* Structure to hold the initial parameters for a compare_and_swap operation
   in HImode and QImode.  */

struct alignment_context
{
  rtx memsi;      /* SI aligned memory location.  */
  rtx shift;      /* Bit offset with regard to lsb.  */
  rtx modemask;   /* Mask of the HQImode shifted by SHIFT bits.  */
  rtx modemaski;  /* ~modemask */
  bool aligned;   /* True if memory is aligned, false else.  */
};

/* A subroutine of s390_expand_cs_hqi and s390_expand_atomic to initialize
   structure AC for transparent simplifying, if the memory alignment is known
   to be at least 32bit.  MEM is the memory location for the actual operation
   and MODE its mode.  */

static void
init_alignment_context (struct alignment_context *ac, rtx mem,
                        machine_mode mode)
{
  ac->shift = GEN_INT (GET_MODE_SIZE (SImode) - GET_MODE_SIZE (mode));
  ac->aligned = (MEM_ALIGN (mem) >= GET_MODE_BITSIZE (SImode));

  if (ac->aligned)
    ac->memsi = adjust_address (mem, SImode, 0); /* Memory is aligned.  */
  else
    {
      /* Alignment is unknown.  */
      rtx byteoffset, addr, align;

      /* Force the address into a register.  */
      addr = force_reg (Pmode, XEXP (mem, 0));

      /* Align it to SImode.  */
      align = expand_simple_binop (Pmode, AND, addr,
                                   GEN_INT (-GET_MODE_SIZE (SImode)),
                                   NULL_RTX, 1, OPTAB_DIRECT);
      /* Generate MEM.  */
      ac->memsi = gen_rtx_MEM (SImode, align);
      MEM_VOLATILE_P (ac->memsi) = MEM_VOLATILE_P (mem);
      set_mem_alias_set (ac->memsi, ALIAS_SET_MEMORY_BARRIER);
      set_mem_align (ac->memsi, GET_MODE_BITSIZE (SImode));

      /* Calculate shiftcount.  */
      byteoffset = expand_simple_binop (Pmode, AND, addr,
                                        GEN_INT (GET_MODE_SIZE (SImode) - 1),
                                        NULL_RTX, 1, OPTAB_DIRECT);
      /* As we already have some offset, evaluate the remaining distance.  */
      ac->shift = expand_simple_binop (SImode, MINUS, ac->shift, byteoffset,
                                      NULL_RTX, 1, OPTAB_DIRECT);
    }

  /* Shift is the byte count, but we need the bitcount.  */
  ac->shift = expand_simple_binop (SImode, ASHIFT, ac->shift, GEN_INT (3),
                                   NULL_RTX, 1, OPTAB_DIRECT);

  /* Calculate masks.  */
  ac->modemask = expand_simple_binop (SImode, ASHIFT,
                                      GEN_INT (GET_MODE_MASK (mode)),
                                      ac->shift, NULL_RTX, 1, OPTAB_DIRECT);
  ac->modemaski = expand_simple_unop (SImode, NOT, ac->modemask,
                                      NULL_RTX, 1);
}

/* A subroutine of s390_expand_cs_hqi.  Insert INS into VAL.  If possible,
   use a single insv insn into SEQ2.  Otherwise, put prep insns in SEQ1 and
   perform the merge in SEQ2.  */

static rtx
s390_two_part_insv (struct alignment_context *ac, rtx *seq1, rtx *seq2,
                    machine_mode mode, rtx val, rtx ins)
{
  rtx tmp;

  if (ac->aligned)
    {
      start_sequence ();
      tmp = copy_to_mode_reg (SImode, val);
      if (s390_expand_insv (tmp, GEN_INT (GET_MODE_BITSIZE (mode)),
                            const0_rtx, ins))
        {
          *seq1 = NULL;
          *seq2 = get_insns ();
          end_sequence ();
          return tmp;
        }
      end_sequence ();
    }

  /* Failed to use insv.  Generate a two part shift and mask.  */
  start_sequence ();
  tmp = s390_expand_mask_and_shift (ins, mode, ac->shift);
  *seq1 = get_insns ();
  end_sequence ();

  start_sequence ();
  tmp = expand_simple_binop (SImode, IOR, tmp, val, NULL_RTX, 1, OPTAB_DIRECT);
  *seq2 = get_insns ();
  end_sequence ();

  return tmp;
}

/* Expand an atomic compare and swap operation for HImode and QImode.  MEM is
   the memory location, CMP the old value to compare MEM with and NEW_RTX the
   value to set if CMP == MEM.  */

void
s390_expand_cs_hqi (machine_mode mode, rtx btarget, rtx vtarget, rtx mem,
                    rtx cmp, rtx new_rtx, bool is_weak)
{
  struct alignment_context ac;
  rtx cmpv, newv, val, cc, seq0, seq1, seq2, seq3;
  rtx res = gen_reg_rtx (SImode);
  rtx_code_label *csloop = NULL, *csend = NULL;

  gcc_assert (MEM_P (mem));

  init_alignment_context (&ac, mem, mode);

  /* Load full word.  Subsequent loads are performed by CS.  */
  val = expand_simple_binop (SImode, AND, ac.memsi, ac.modemaski,
                             NULL_RTX, 1, OPTAB_DIRECT);

  /* Prepare insertions of cmp and new_rtx into the loaded value.  When
     possible, we try to use insv to make this happen efficiently.  If
     that fails we'll generate code both inside and outside the loop.  */
  cmpv = s390_two_part_insv (&ac, &seq0, &seq2, mode, val, cmp);
  newv = s390_two_part_insv (&ac, &seq1, &seq3, mode, val, new_rtx);

  if (seq0)
    emit_insn (seq0);
  if (seq1)
    emit_insn (seq1);

  /* Start CS loop.  */
  if (!is_weak)
    {
      /* Begin assuming success.  */
      emit_move_insn (btarget, const1_rtx);

      csloop = gen_label_rtx ();
      csend = gen_label_rtx ();
      emit_label (csloop);
    }

  /* val = "<mem>00..0<mem>"
   * cmp = "00..0<cmp>00..0"
   * new = "00..0<new>00..0"
   */

  emit_insn (seq2);
  emit_insn (seq3);

  cc = s390_emit_compare_and_swap (EQ, res, ac.memsi, cmpv, newv);
  if (is_weak)
    emit_insn (gen_cstorecc4 (btarget, cc, XEXP (cc, 0), XEXP (cc, 1)));
  else
    {
      rtx tmp;

      /* Jump to end if we're done (likely?).  */
      s390_emit_jump (csend, cc);

      /* Check for changes outside mode, and loop internal if so.
         Arrange the moves so that the compare is adjacent to the
         branch so that we can generate CRJ.  */
      tmp = copy_to_reg (val);
      force_expand_binop (SImode, and_optab, res, ac.modemaski, val,
                          1, OPTAB_DIRECT);
      cc = s390_emit_compare (NE, val, tmp);
      s390_emit_jump (csloop, cc);

      /* Failed.  */
      emit_move_insn (btarget, const0_rtx);
      emit_label (csend);
    }

  /* Return the correct part of the bitfield.  */
  convert_move (vtarget, expand_simple_binop (SImode, LSHIFTRT, res, ac.shift,
                                              NULL_RTX, 1, OPTAB_DIRECT), 1);
}

/* Expand an atomic operation CODE of mode MODE.  MEM is the memory location
   and VAL the value to play with.  If AFTER is true then store the value
   MEM holds after the operation, if AFTER is false then store the value MEM
   holds before the operation.  If TARGET is zero then discard that value, else
   store it to TARGET.  */

void
s390_expand_atomic (machine_mode mode, enum rtx_code code,
                    rtx target, rtx mem, rtx val, bool after)
{
  struct alignment_context ac;
  rtx cmp;
  rtx new_rtx = gen_reg_rtx (SImode);
  rtx orig = gen_reg_rtx (SImode);
  rtx_code_label *csloop = gen_label_rtx ();

  gcc_assert (!target || register_operand (target, VOIDmode));
  gcc_assert (MEM_P (mem));

  init_alignment_context (&ac, mem, mode);

  /* Shift val to the correct bit positions.
     Preserve "icm", but prevent "ex icm".  */
  if (!(ac.aligned && code == SET && MEM_P (val)))
    val = s390_expand_mask_and_shift (val, mode, ac.shift);

  /* Further preparation insns.  */
  if (code == PLUS || code == MINUS)
    emit_move_insn (orig, val);
  else if (code == MULT || code == AND) /* val = "11..1<val>11..1" */
    val = expand_simple_binop (SImode, XOR, val, ac.modemaski,
                               NULL_RTX, 1, OPTAB_DIRECT);

  /* Load full word.  Subsequent loads are performed by CS.  */
  cmp = force_reg (SImode, ac.memsi);

  /* Start CS loop.  */
  emit_label (csloop);
  emit_move_insn (new_rtx, cmp);

  /* Patch new with val at correct position.  */
  switch (code)
    {
    case PLUS:
    case MINUS:
      val = expand_simple_binop (SImode, code, new_rtx, orig,
                                 NULL_RTX, 1, OPTAB_DIRECT);
      val = expand_simple_binop (SImode, AND, val, ac.modemask,
                                 NULL_RTX, 1, OPTAB_DIRECT);
      /* FALLTHRU */
    case SET:
      if (ac.aligned && MEM_P (val))
        store_bit_field (new_rtx, GET_MODE_BITSIZE (mode), 0,
                         0, 0, SImode, val);
      else
        {
          new_rtx = expand_simple_binop (SImode, AND, new_rtx, ac.modemaski,
                                     NULL_RTX, 1, OPTAB_DIRECT);
          new_rtx = expand_simple_binop (SImode, IOR, new_rtx, val,
                                     NULL_RTX, 1, OPTAB_DIRECT);
        }
      break;
    case AND:
    case IOR:
    case XOR:
      new_rtx = expand_simple_binop (SImode, code, new_rtx, val,
                                 NULL_RTX, 1, OPTAB_DIRECT);
      break;
    case MULT: /* NAND */
      new_rtx = expand_simple_binop (SImode, AND, new_rtx, val,
                                 NULL_RTX, 1, OPTAB_DIRECT);
      new_rtx = expand_simple_binop (SImode, XOR, new_rtx, ac.modemask,
                                 NULL_RTX, 1, OPTAB_DIRECT);
      break;
    default:
      gcc_unreachable ();
    }

  s390_emit_jump (csloop, s390_emit_compare_and_swap (NE, cmp,
                                                      ac.memsi, cmp, new_rtx));

  /* Return the correct part of the bitfield.  */
  if (target)
    convert_move (target, expand_simple_binop (SImode, LSHIFTRT,
                                               after ? new_rtx : cmp, ac.shift,
                                               NULL_RTX, 1, OPTAB_DIRECT), 1);
}

/* This is called from dwarf2out.c via TARGET_ASM_OUTPUT_DWARF_DTPREL.
   We need to emit DTP-relative relocations.  */

static void s390_output_dwarf_dtprel (FILE *, int, rtx) ATTRIBUTE_UNUSED;

static void
s390_output_dwarf_dtprel (FILE *file, int size, rtx x)
{
  switch (size)
    {
    case 4:
      fputs ("\t.long\t", file);
      break;
    case 8:
      fputs ("\t.quad\t", file);
      break;
    default:
      gcc_unreachable ();
    }
  output_addr_const (file, x);
  fputs ("@DTPOFF", file);
}

#ifdef TARGET_ALTERNATE_LONG_DOUBLE_MANGLING
/* Implement TARGET_MANGLE_TYPE.  */

static const char *
s390_mangle_type (const_tree type)
{
  if (TYPE_MAIN_VARIANT (type) == long_double_type_node
      && TARGET_LONG_DOUBLE_128)
    return "g";

  /* For all other types, use normal C++ mangling.  */
  return NULL;
}
#endif

/* In the name of slightly smaller debug output, and to cater to
   general assembler lossage, recognize various UNSPEC sequences
   and turn them back into a direct symbol reference.  */

static rtx
s390_delegitimize_address (rtx orig_x)
{
  rtx x, y;

  orig_x = delegitimize_mem_from_attrs (orig_x);
  x = orig_x;

  /* Extract the symbol ref from:
     (plus:SI (reg:SI 12 %r12)
              (const:SI (unspec:SI [(symbol_ref/f:SI ("*.LC0"))]
                                    UNSPEC_GOTOFF/PLTOFF)))
     and
     (plus:SI (reg:SI 12 %r12)
              (const:SI (plus:SI (unspec:SI [(symbol_ref:SI ("L"))]
                                             UNSPEC_GOTOFF/PLTOFF)
                                 (const_int 4 [0x4]))))  */
  if (GET_CODE (x) == PLUS
      && REG_P (XEXP (x, 0))
      && REGNO (XEXP (x, 0)) == PIC_OFFSET_TABLE_REGNUM
      && GET_CODE (XEXP (x, 1)) == CONST)
    {
      HOST_WIDE_INT offset = 0;

      /* The const operand.  */
      y = XEXP (XEXP (x, 1), 0);

      if (GET_CODE (y) == PLUS
          && GET_CODE (XEXP (y, 1)) == CONST_INT)
        {
          offset = INTVAL (XEXP (y, 1));
          y = XEXP (y, 0);
        }

      if (GET_CODE (y) == UNSPEC
          && (XINT (y, 1) == UNSPEC_GOTOFF
              || XINT (y, 1) == UNSPEC_PLTOFF))
        return plus_constant (Pmode, XVECEXP (y, 0, 0), offset);
    }

  if (GET_CODE (x) != MEM)
    return orig_x;

  x = XEXP (x, 0);
  if (GET_CODE (x) == PLUS
      && GET_CODE (XEXP (x, 1)) == CONST
      && GET_CODE (XEXP (x, 0)) == REG
      && REGNO (XEXP (x, 0)) == PIC_OFFSET_TABLE_REGNUM)
    {
      y = XEXP (XEXP (x, 1), 0);
      if (GET_CODE (y) == UNSPEC
          && XINT (y, 1) == UNSPEC_GOT)
        y = XVECEXP (y, 0, 0);
      else
        return orig_x;
    }
  else if (GET_CODE (x) == CONST)
    {
      /* Extract the symbol ref from:
         (mem:QI (const:DI (unspec:DI [(symbol_ref:DI ("foo"))]
                                       UNSPEC_PLT/GOTENT)))  */

      y = XEXP (x, 0);
      if (GET_CODE (y) == UNSPEC
          && (XINT (y, 1) == UNSPEC_GOTENT
              || XINT (y, 1) == UNSPEC_PLT))
        y = XVECEXP (y, 0, 0);
      else
        return orig_x;
    }
  else
    return orig_x;

  if (GET_MODE (orig_x) != Pmode)
    {
      if (GET_MODE (orig_x) == BLKmode)
        return orig_x;
      y = lowpart_subreg (GET_MODE (orig_x), y, Pmode);
      if (y == NULL_RTX)
        return orig_x;
    }
  return y;
}

/* Output operand OP to stdio stream FILE.
   OP is an address (register + offset) which is not used to address data;
   instead the rightmost bits are interpreted as the value.  */

static void
print_shift_count_operand (FILE *file, rtx op)
{
  HOST_WIDE_INT offset;
  rtx base;

  /* Extract base register and offset.  */
  if (!s390_decompose_shift_count (op, &base, &offset))
    gcc_unreachable ();

  /* Sanity check.  */
  if (base)
    {
      gcc_assert (GET_CODE (base) == REG);
      gcc_assert (REGNO (base) < FIRST_PSEUDO_REGISTER);
      gcc_assert (REGNO_REG_CLASS (REGNO (base)) == ADDR_REGS);
    }

  /* Offsets are constricted to twelve bits.  */
  fprintf (file, HOST_WIDE_INT_PRINT_DEC, offset & ((1 << 12) - 1));
  if (base)
    fprintf (file, "(%s)", reg_names[REGNO (base)]);
}

/* Returns -1 if the function should not be made hotpatchable.  Otherwise it
   returns a number >= 0 that is the desired size of the hotpatch trampoline
   in halfwords. */

static int s390_function_num_hotpatch_trampoline_halfwords (tree decl,
                                                            bool do_warn)
{
  tree attr;

  if (DECL_DECLARED_INLINE_P (decl)
      || DECL_ARTIFICIAL (decl)
      || MAIN_NAME_P (DECL_NAME (decl)))
    {
      /* - Explicitly inlined functions cannot be hotpatched.
         - Artificial functions need not be hotpatched.
         - Making the main function hotpatchable is useless. */
      return -1;
    }
  attr = lookup_attribute ("hotpatch", DECL_ATTRIBUTES (decl));
  if (attr || s390_hotpatch_trampoline_halfwords >= 0)
    {
      if (lookup_attribute ("always_inline", DECL_ATTRIBUTES (decl)))
        {
          if (do_warn)
            warning (OPT_Wattributes, "function %qE with the %qs attribute"
                     " is not hotpatchable", DECL_NAME (decl), "always_inline");
          return -1;
        }
      else
        {
          return (attr) ?
            get_hotpatch_attribute (attr) : s390_hotpatch_trampoline_halfwords;
        }
    }

  return -1;
}

/* Hook to determine if one function can safely inline another.  */

static bool
s390_can_inline_p (tree caller, tree callee)
{
  if (s390_function_num_hotpatch_trampoline_halfwords (callee, false) >= 0)
    return false;

  return default_target_can_inline_p (caller, callee);
}

/* Write the extra assembler code needed to declare a function properly.  */

void
s390_asm_output_function_label (FILE *asm_out_file, const char *fname,
                                tree decl)
{
  int hotpatch_trampoline_halfwords = -1;

  if (decl)
    {
      hotpatch_trampoline_halfwords =
        s390_function_num_hotpatch_trampoline_halfwords (decl, true);
      if (hotpatch_trampoline_halfwords >= 0
          && decl_function_context (decl) != NULL_TREE)
        {
          warning_at (DECL_SOURCE_LOCATION (decl), OPT_mhotpatch,
                      "hotpatching is not compatible with nested functions");
          hotpatch_trampoline_halfwords = -1;
        }
    }

  if (hotpatch_trampoline_halfwords > 0)
    {
      int i;

      /* Add a trampoline code area before the function label and initialize it
         with two-byte nop instructions.  This area can be overwritten with code
         that jumps to a patched version of the function.  */
      for (i = 0; i < hotpatch_trampoline_halfwords; i++)
        asm_fprintf (asm_out_file, "\tnopr\t%%r7\n");
      /* Note:  The function label must be aligned so that (a) the bytes of the
         following nop do not cross a cacheline boundary, and (b) a jump address
         (eight bytes for 64 bit targets, 4 bytes for 32 bit targets) can be
         stored directly before the label without crossing a cacheline
         boundary.  All this is necessary to make sure the trampoline code can
         be changed atomically.  */
    }

  ASM_OUTPUT_LABEL (asm_out_file, fname);

  /* Output a four-byte nop if hotpatching is enabled.  This can be overwritten
     atomically with a relative backwards jump to the trampoline area.  */
  if (hotpatch_trampoline_halfwords >= 0)
    asm_fprintf (asm_out_file, "\tnop\t0\n");
}

/* Output machine-dependent UNSPECs occurring in address constant X
   in assembler syntax to stdio stream FILE.  Returns true if the
   constant X could be recognized, false otherwise.  */

static bool
s390_output_addr_const_extra (FILE *file, rtx x)
{
  if (GET_CODE (x) == UNSPEC && XVECLEN (x, 0) == 1)
    switch (XINT (x, 1))
      {
      case UNSPEC_GOTENT:
        output_addr_const (file, XVECEXP (x, 0, 0));
        fprintf (file, "@GOTENT");
        return true;
      case UNSPEC_GOT:
        output_addr_const (file, XVECEXP (x, 0, 0));
        fprintf (file, "@GOT");
        return true;
      case UNSPEC_GOTOFF:
        output_addr_const (file, XVECEXP (x, 0, 0));
        fprintf (file, "@GOTOFF");
        return true;
      case UNSPEC_PLT:
        output_addr_const (file, XVECEXP (x, 0, 0));
        fprintf (file, "@PLT");
        return true;
      case UNSPEC_PLTOFF:
        output_addr_const (file, XVECEXP (x, 0, 0));
        fprintf (file, "@PLTOFF");
        return true;
      case UNSPEC_TLSGD:
        output_addr_const (file, XVECEXP (x, 0, 0));
        fprintf (file, "@TLSGD");
        return true;
      case UNSPEC_TLSLDM:
        assemble_name (file, get_some_local_dynamic_name ());
        fprintf (file, "@TLSLDM");
        return true;
      case UNSPEC_DTPOFF:
        output_addr_const (file, XVECEXP (x, 0, 0));
        fprintf (file, "@DTPOFF");
        return true;
      case UNSPEC_NTPOFF:
        output_addr_const (file, XVECEXP (x, 0, 0));
        fprintf (file, "@NTPOFF");
        return true;
      case UNSPEC_GOTNTPOFF:
        output_addr_const (file, XVECEXP (x, 0, 0));
        fprintf (file, "@GOTNTPOFF");
        return true;
      case UNSPEC_INDNTPOFF:
        output_addr_const (file, XVECEXP (x, 0, 0));
        fprintf (file, "@INDNTPOFF");
        return true;
      }

  if (GET_CODE (x) == UNSPEC && XVECLEN (x, 0) == 2)
    switch (XINT (x, 1))
      {
      case UNSPEC_POOL_OFFSET:
        x = gen_rtx_MINUS (GET_MODE (x), XVECEXP (x, 0, 0), XVECEXP (x, 0, 1));
        output_addr_const (file, x);
        return true;
      }
  return false;
}

/* Output address operand ADDR in assembler syntax to
   stdio stream FILE.  */

void
print_operand_address (FILE *file, rtx addr)
{
  struct s390_address ad;

  if (s390_loadrelative_operand_p (addr, NULL, NULL))
    {
      if (!TARGET_Z10)
        {
          output_operand_lossage ("symbolic memory references are "
                                  "only supported on z10 or later");
          return;
        }
      output_addr_const (file, addr);
      return;
    }

  if (!s390_decompose_address (addr, &ad)
      || (ad.base && !REGNO_OK_FOR_BASE_P (REGNO (ad.base)))
      || (ad.indx && !REGNO_OK_FOR_INDEX_P (REGNO (ad.indx))))
    output_operand_lossage ("cannot decompose address");

  if (ad.disp)
    output_addr_const (file, ad.disp);
  else
    fprintf (file, "0");

  if (ad.base && ad.indx)
    fprintf (file, "(%s,%s)", reg_names[REGNO (ad.indx)],
                              reg_names[REGNO (ad.base)]);
  else if (ad.base)
    fprintf (file, "(%s)", reg_names[REGNO (ad.base)]);
}

/* Output operand X in assembler syntax to stdio stream FILE.
   CODE specified the format flag.  The following format flags
   are recognized:

    'C': print opcode suffix for branch condition.
    'D': print opcode suffix for inverse branch condition.
    'E': print opcode suffix for branch on index instruction.
    'G': print the size of the operand in bytes.
    'J': print tls_load/tls_gdcall/tls_ldcall suffix
    'M': print the second word of a TImode operand.
    'N': print the second word of a DImode operand.
    'O': print only the displacement of a memory reference.
    'R': print only the base register of a memory reference.
    'S': print S-type memory reference (base+displacement).
    'Y': print shift count operand.

    'b': print integer X as if it's an unsigned byte.
    'c': print integer X as if it's an signed byte.
    'e': "end" of DImode contiguous bitmask X.
    'f': "end" of SImode contiguous bitmask X.
    'h': print integer X as if it's a signed halfword.
    'i': print the first nonzero HImode part of X.
    'j': print the first HImode part unequal to -1 of X.
    'k': print the first nonzero SImode part of X.
    'm': print the first SImode part unequal to -1 of X.
    'o': print integer X as if it's an unsigned 32bit word.
    's': "start" of DImode contiguous bitmask X.
    't': "start" of SImode contiguous bitmask X.
    'x': print integer X as if it's an unsigned halfword.
*/

void
print_operand (FILE *file, rtx x, int code)
{
  HOST_WIDE_INT ival;

  switch (code)
    {
    case 'C':
      fprintf (file, s390_branch_condition_mnemonic (x, FALSE));
      return;

    case 'D':
      fprintf (file, s390_branch_condition_mnemonic (x, TRUE));
      return;

    case 'E':
      if (GET_CODE (x) == LE)
        fprintf (file, "l");
      else if (GET_CODE (x) == GT)
        fprintf (file, "h");
      else
        output_operand_lossage ("invalid comparison operator "
                                "for 'E' output modifier");
      return;

    case 'J':
      if (GET_CODE (x) == SYMBOL_REF)
        {
          fprintf (file, "%s", ":tls_load:");
          output_addr_const (file, x);
        }
      else if (GET_CODE (x) == UNSPEC && XINT (x, 1) == UNSPEC_TLSGD)
        {
          fprintf (file, "%s", ":tls_gdcall:");
          output_addr_const (file, XVECEXP (x, 0, 0));
        }
      else if (GET_CODE (x) == UNSPEC && XINT (x, 1) == UNSPEC_TLSLDM)
        {
          fprintf (file, "%s", ":tls_ldcall:");
          const char *name = get_some_local_dynamic_name ();
          gcc_assert (name);
          assemble_name (file, name);
        }
      else
        output_operand_lossage ("invalid reference for 'J' output modifier");
      return;

    case 'G':
      fprintf (file, "%u", GET_MODE_SIZE (GET_MODE (x)));
      return;

    case 'O':
      {
        struct s390_address ad;
        int ret;

        if (!MEM_P (x))
          {
            output_operand_lossage ("memory reference expected for "
                                    "'O' output modifier");
            return;
          }

        ret = s390_decompose_address (XEXP (x, 0), &ad);

        if (!ret
            || (ad.base && !REGNO_OK_FOR_BASE_P (REGNO (ad.base)))
            || ad.indx)
          {
            output_operand_lossage ("invalid address for 'O' output modifier");
            return;
          }

        if (ad.disp)
          output_addr_const (file, ad.disp);
        else
          fprintf (file, "0");
      }
      return;

    case 'R':
      {
        struct s390_address ad;
        int ret;

        if (!MEM_P (x))
          {
            output_operand_lossage ("memory reference expected for "
                                    "'R' output modifier");
            return;
          }

        ret = s390_decompose_address (XEXP (x, 0), &ad);

        if (!ret
            || (ad.base && !REGNO_OK_FOR_BASE_P (REGNO (ad.base)))
            || ad.indx)
          {
            output_operand_lossage ("invalid address for 'R' output modifier");
            return;
          }

        if (ad.base)
          fprintf (file, "%s", reg_names[REGNO (ad.base)]);
        else
          fprintf (file, "0");
      }
      return;

    case 'S':
      {
        struct s390_address ad;
        int ret;

        if (!MEM_P (x))
          {
            output_operand_lossage ("memory reference expected for "
                                    "'S' output modifier");
            return;
          }
        ret = s390_decompose_address (XEXP (x, 0), &ad);

        if (!ret
            || (ad.base && !REGNO_OK_FOR_BASE_P (REGNO (ad.base)))
            || ad.indx)
          {
            output_operand_lossage ("invalid address for 'S' output modifier");
            return;
          }

        if (ad.disp)
          output_addr_const (file, ad.disp);
        else
          fprintf (file, "0");

        if (ad.base)
          fprintf (file, "(%s)", reg_names[REGNO (ad.base)]);
      }
      return;

    case 'N':
      if (GET_CODE (x) == REG)
        x = gen_rtx_REG (GET_MODE (x), REGNO (x) + 1);
      else if (GET_CODE (x) == MEM)
        x = change_address (x, VOIDmode,
                            plus_constant (Pmode, XEXP (x, 0), 4));
      else
        output_operand_lossage ("register or memory expression expected "
                                "for 'N' output modifier");
      break;

    case 'M':
      if (GET_CODE (x) == REG)
        x = gen_rtx_REG (GET_MODE (x), REGNO (x) + 1);
      else if (GET_CODE (x) == MEM)
        x = change_address (x, VOIDmode,
                            plus_constant (Pmode, XEXP (x, 0), 8));
      else
        output_operand_lossage ("register or memory expression expected "
                                "for 'M' output modifier");
      break;

    case 'Y':
      print_shift_count_operand (file, x);
      return;
    }

  switch (GET_CODE (x))
    {
    case REG:
      fprintf (file, "%s", reg_names[REGNO (x)]);
      break;

    case MEM:
      output_address (XEXP (x, 0));
      break;

    case CONST:
    case CODE_LABEL:
    case LABEL_REF:
    case SYMBOL_REF:
      output_addr_const (file, x);
      break;

    case CONST_INT:
      ival = INTVAL (x);
      switch (code)
        {
        case 0:
          break;
        case 'b':
          ival &= 0xff;
          break;
        case 'c':
          ival = ((ival & 0xff) ^ 0x80) - 0x80;
          break;
        case 'x':
          ival &= 0xffff;
          break;
        case 'h':
          ival = ((ival & 0xffff) ^ 0x8000) - 0x8000;
          break;
        case 'i':
          ival = s390_extract_part (x, HImode, 0);
          break;
        case 'j':
          ival = s390_extract_part (x, HImode, -1);
          break;
        case 'k':
          ival = s390_extract_part (x, SImode, 0);
          break;
        case 'm':
          ival = s390_extract_part (x, SImode, -1);
          break;
        case 'o':
          ival &= 0xffffffff;
          break;
        case 'e': case 'f':
        case 's': case 't':
          {
            int pos, len;
            bool ok;

            len = (code == 's' || code == 'e' ? 64 : 32);
            ok = s390_contiguous_bitmask_p (ival, len, &pos, &len);
            gcc_assert (ok);
            if (code == 's' || code == 't')
              ival = 64 - pos - len;
            else
              ival = 64 - 1 - pos;
          }
          break;
        default:
          output_operand_lossage ("invalid constant for output modifier '%c'", code);
        }
      fprintf (file, HOST_WIDE_INT_PRINT_DEC, ival);
      break;

    case CONST_DOUBLE:
      gcc_assert (GET_MODE (x) == VOIDmode);
      if (code == 'b')
        fprintf (file, HOST_WIDE_INT_PRINT_DEC, CONST_DOUBLE_LOW (x) & 0xff);
      else if (code == 'x')
        fprintf (file, HOST_WIDE_INT_PRINT_DEC, CONST_DOUBLE_LOW (x) & 0xffff);
      else if (code == 'h')
        fprintf (file, HOST_WIDE_INT_PRINT_DEC,
                 ((CONST_DOUBLE_LOW (x) & 0xffff) ^ 0x8000) - 0x8000);
      else
        {
          if (code == 0)
            output_operand_lossage ("invalid constant - try using "
                                    "an output modifier");
          else
            output_operand_lossage ("invalid constant for output modifier '%c'",
                                    code);
        }
      break;

    default:
      if (code == 0)
        output_operand_lossage ("invalid expression - try using "
                                "an output modifier");
      else
        output_operand_lossage ("invalid expression for output "
                                "modifier '%c'", code);
      break;
    }
}

/* Target hook for assembling integer objects.  We need to define it
   here to work a round a bug in some versions of GAS, which couldn't
   handle values smaller than INT_MIN when printed in decimal.  */

static bool
s390_assemble_integer (rtx x, unsigned int size, int aligned_p)
{
  if (size == 8 && aligned_p
      && GET_CODE (x) == CONST_INT && INTVAL (x) < INT_MIN)
    {
      fprintf (asm_out_file, "\t.quad\t" HOST_WIDE_INT_PRINT_HEX "\n",
               INTVAL (x));
      return true;
    }
  return default_assemble_integer (x, size, aligned_p);
}

/* Returns true if register REGNO is used  for forming
   a memory address in expression X.  */

static bool
reg_used_in_mem_p (int regno, rtx x)
{
  enum rtx_code code = GET_CODE (x);
  int i, j;
  const char *fmt;

  if (code == MEM)
    {
      if (refers_to_regno_p (regno, regno+1,
                             XEXP (x, 0), 0))
        return true;
    }
  else if (code == SET
           && GET_CODE (SET_DEST (x)) == PC)
    {
      if (refers_to_regno_p (regno, regno+1,
                             SET_SRC (x), 0))
        return true;
    }

  fmt = GET_RTX_FORMAT (code);
  for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
    {
      if (fmt[i] == 'e'
          && reg_used_in_mem_p (regno, XEXP (x, i)))
        return true;

      else if (fmt[i] == 'E')
        for (j = 0; j < XVECLEN (x, i); j++)
          if (reg_used_in_mem_p (regno, XVECEXP (x, i, j)))
            return true;
    }
  return false;
}

/* Returns true if expression DEP_RTX sets an address register
   used by instruction INSN to address memory.  */

static bool
addr_generation_dependency_p (rtx dep_rtx, rtx_insn *insn)
{
  rtx target, pat;

  if (NONJUMP_INSN_P (dep_rtx))
    dep_rtx = PATTERN (dep_rtx);

  if (GET_CODE (dep_rtx) == SET)
    {
      target = SET_DEST (dep_rtx);
      if (GET_CODE (target) == STRICT_LOW_PART)
        target = XEXP (target, 0);
      while (GET_CODE (target) == SUBREG)
        target = SUBREG_REG (target);

      if (GET_CODE (target) == REG)
        {
          int regno = REGNO (target);

          if (s390_safe_attr_type (insn) == TYPE_LA)
            {
              pat = PATTERN (insn);
              if (GET_CODE (pat) == PARALLEL)
                {
                  gcc_assert (XVECLEN (pat, 0) == 2);
                  pat = XVECEXP (pat, 0, 0);
                }
              gcc_assert (GET_CODE (pat) == SET);
              return refers_to_regno_p (regno, regno+1, SET_SRC (pat), 0);
            }
          else if (get_attr_atype (insn) == ATYPE_AGEN)
            return reg_used_in_mem_p (regno, PATTERN (insn));
        }
    }
  return false;
}

/* Return 1, if dep_insn sets register used in insn in the agen unit.  */

int
s390_agen_dep_p (rtx_insn *dep_insn, rtx_insn *insn)
{
  rtx dep_rtx = PATTERN (dep_insn);
  int i;

  if (GET_CODE (dep_rtx) == SET
      && addr_generation_dependency_p (dep_rtx, insn))
    return 1;
  else if (GET_CODE (dep_rtx) == PARALLEL)
    {
      for (i = 0; i < XVECLEN (dep_rtx, 0); i++)
        {
          if (addr_generation_dependency_p (XVECEXP (dep_rtx, 0, i), insn))
            return 1;
        }
    }
  return 0;
}


/* A C statement (sans semicolon) to update the integer scheduling priority
   INSN_PRIORITY (INSN).  Increase the priority to execute the INSN earlier,
   reduce the priority to execute INSN later.  Do not define this macro if
   you do not need to adjust the scheduling priorities of insns.

   A STD instruction should be scheduled earlier,
   in order to use the bypass.  */
static int
s390_adjust_priority (rtx_insn *insn, int priority)
{
  if (! INSN_P (insn))
    return priority;

  if (s390_tune != PROCESSOR_2084_Z990
      && s390_tune != PROCESSOR_2094_Z9_109
      && s390_tune != PROCESSOR_2097_Z10
      && s390_tune != PROCESSOR_2817_Z196
      && s390_tune != PROCESSOR_2827_ZEC12)
    return priority;

  switch (s390_safe_attr_type (insn))
    {
      case TYPE_FSTOREDF:
      case TYPE_FSTORESF:
        priority = priority << 3;
        break;
      case TYPE_STORE:
      case TYPE_STM:
        priority = priority << 1;
        break;
      default:
        break;
    }
  return priority;
}


/* The number of instructions that can be issued per cycle.  */

static int
s390_issue_rate (void)
{
  switch (s390_tune)
    {
    case PROCESSOR_2084_Z990:
    case PROCESSOR_2094_Z9_109:
    case PROCESSOR_2817_Z196:
      return 3;
    case PROCESSOR_2097_Z10:
    case PROCESSOR_2827_ZEC12:
      return 2;
    default:
      return 1;
    }
}

static int
s390_first_cycle_multipass_dfa_lookahead (void)
{
  return 4;
}

/* Annotate every literal pool reference in X by an UNSPEC_LTREF expression.
   Fix up MEMs as required.  */

static void
annotate_constant_pool_refs (rtx *x)
{
  int i, j;
  const char *fmt;

  gcc_assert (GET_CODE (*x) != SYMBOL_REF
              || !CONSTANT_POOL_ADDRESS_P (*x));

  /* Literal pool references can only occur inside a MEM ...  */
  if (GET_CODE (*x) == MEM)
    {
      rtx memref = XEXP (*x, 0);

      if (GET_CODE (memref) == SYMBOL_REF
          && CONSTANT_POOL_ADDRESS_P (memref))
        {
          rtx base = cfun->machine->base_reg;
          rtx addr = gen_rtx_UNSPEC (Pmode, gen_rtvec (2, memref, base),
                                     UNSPEC_LTREF);

          *x = replace_equiv_address (*x, addr);
          return;
        }

      if (GET_CODE (memref) == CONST
          && GET_CODE (XEXP (memref, 0)) == PLUS
          && GET_CODE (XEXP (XEXP (memref, 0), 1)) == CONST_INT
          && GET_CODE (XEXP (XEXP (memref, 0), 0)) == SYMBOL_REF
          && CONSTANT_POOL_ADDRESS_P (XEXP (XEXP (memref, 0), 0)))
        {
          HOST_WIDE_INT off = INTVAL (XEXP (XEXP (memref, 0), 1));
          rtx sym = XEXP (XEXP (memref, 0), 0);
          rtx base = cfun->machine->base_reg;
          rtx addr = gen_rtx_UNSPEC (Pmode, gen_rtvec (2, sym, base),
                                     UNSPEC_LTREF);

          *x = replace_equiv_address (*x, plus_constant (Pmode, addr, off));
          return;
        }
    }

  /* ... or a load-address type pattern.  */
  if (GET_CODE (*x) == SET)
    {
      rtx addrref = SET_SRC (*x);

      if (GET_CODE (addrref) == SYMBOL_REF
          && CONSTANT_POOL_ADDRESS_P (addrref))
        {
          rtx base = cfun->machine->base_reg;
          rtx addr = gen_rtx_UNSPEC (Pmode, gen_rtvec (2, addrref, base),
                                     UNSPEC_LTREF);

          SET_SRC (*x) = addr;
          return;
        }

      if (GET_CODE (addrref) == CONST
          && GET_CODE (XEXP (addrref, 0)) == PLUS
          && GET_CODE (XEXP (XEXP (addrref, 0), 1)) == CONST_INT
          && GET_CODE (XEXP (XEXP (addrref, 0), 0)) == SYMBOL_REF
          && CONSTANT_POOL_ADDRESS_P (XEXP (XEXP (addrref, 0), 0)))
        {
          HOST_WIDE_INT off = INTVAL (XEXP (XEXP (addrref, 0), 1));
          rtx sym = XEXP (XEXP (addrref, 0), 0);
          rtx base = cfun->machine->base_reg;
          rtx addr = gen_rtx_UNSPEC (Pmode, gen_rtvec (2, sym, base),
                                     UNSPEC_LTREF);

          SET_SRC (*x) = plus_constant (Pmode, addr, off);
          return;
        }
    }

  /* Annotate LTREL_BASE as well.  */
  if (GET_CODE (*x) == UNSPEC
      && XINT (*x, 1) == UNSPEC_LTREL_BASE)
    {
      rtx base = cfun->machine->base_reg;
      *x = gen_rtx_UNSPEC (Pmode, gen_rtvec (2, XVECEXP (*x, 0, 0), base),
                                  UNSPEC_LTREL_BASE);
      return;
    }

  fmt = GET_RTX_FORMAT (GET_CODE (*x));
  for (i = GET_RTX_LENGTH (GET_CODE (*x)) - 1; i >= 0; i--)
    {
      if (fmt[i] == 'e')
        {
          annotate_constant_pool_refs (&XEXP (*x, i));
        }
      else if (fmt[i] == 'E')
        {
          for (j = 0; j < XVECLEN (*x, i); j++)
            annotate_constant_pool_refs (&XVECEXP (*x, i, j));
        }
    }
}

/* Split all branches that exceed the maximum distance.
   Returns true if this created a new literal pool entry.  */

static int
s390_split_branches (void)
{
  rtx temp_reg = gen_rtx_REG (Pmode, RETURN_REGNUM);
  int new_literal = 0, ret;
  rtx_insn *insn;
  rtx pat, target;
  rtx *label;

  /* We need correct insn addresses.  */

  shorten_branches (get_insns ());

  /* Find all branches that exceed 64KB, and split them.  */

  for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
    {
      if (! JUMP_P (insn) || tablejump_p (insn, NULL, NULL))
        continue;

      pat = PATTERN (insn);
      if (GET_CODE (pat) == PARALLEL)
        pat = XVECEXP (pat, 0, 0);
      if (GET_CODE (pat) != SET || SET_DEST (pat) != pc_rtx)
        continue;

      if (GET_CODE (SET_SRC (pat)) == LABEL_REF)
        {
          label = &SET_SRC (pat);
        }
      else if (GET_CODE (SET_SRC (pat)) == IF_THEN_ELSE)
        {
          if (GET_CODE (XEXP (SET_SRC (pat), 1)) == LABEL_REF)
            label = &XEXP (SET_SRC (pat), 1);
          else if (GET_CODE (XEXP (SET_SRC (pat), 2)) == LABEL_REF)
            label = &XEXP (SET_SRC (pat), 2);
          else
            continue;
        }
      else
        continue;

      if (get_attr_length (insn) <= 4)
        continue;

      /* We are going to use the return register as scratch register,
         make sure it will be saved/restored by the prologue/epilogue.  */
      cfun_frame_layout.save_return_addr_p = 1;

      if (!flag_pic)
        {
          new_literal = 1;
          rtx mem = force_const_mem (Pmode, *label);
          rtx_insn *set_insn = emit_insn_before (gen_rtx_SET (Pmode, temp_reg, mem), insn);
          INSN_ADDRESSES_NEW (set_insn, -1);
          annotate_constant_pool_refs (&PATTERN (set_insn));

          target = temp_reg;
        }
      else
        {
          new_literal = 1;
          target = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, *label),
                                   UNSPEC_LTREL_OFFSET);
          target = gen_rtx_CONST (Pmode, target);
          target = force_const_mem (Pmode, target);
          rtx_insn *set_insn = emit_insn_before (gen_rtx_SET (Pmode, temp_reg, target), insn);
          INSN_ADDRESSES_NEW (set_insn, -1);
          annotate_constant_pool_refs (&PATTERN (set_insn));

          target = gen_rtx_UNSPEC (Pmode, gen_rtvec (2, XEXP (target, 0),
                                                        cfun->machine->base_reg),
                                   UNSPEC_LTREL_BASE);
          target = gen_rtx_PLUS (Pmode, temp_reg, target);
        }

      ret = validate_change (insn, label, target, 0);
      gcc_assert (ret);
    }

  return new_literal;
}


/* Find an annotated literal pool symbol referenced in RTX X,
   and store it at REF.  Will abort if X contains references to
   more than one such pool symbol; multiple references to the same
   symbol are allowed, however.

   The rtx pointed to by REF must be initialized to NULL_RTX
   by the caller before calling this routine.  */

static void
find_constant_pool_ref (rtx x, rtx *ref)
{
  int i, j;
  const char *fmt;

  /* Ignore LTREL_BASE references.  */
  if (GET_CODE (x) == UNSPEC
      && XINT (x, 1) == UNSPEC_LTREL_BASE)
    return;
  /* Likewise POOL_ENTRY insns.  */
  if (GET_CODE (x) == UNSPEC_VOLATILE
      && XINT (x, 1) == UNSPECV_POOL_ENTRY)
    return;

  gcc_assert (GET_CODE (x) != SYMBOL_REF
              || !CONSTANT_POOL_ADDRESS_P (x));

  if (GET_CODE (x) == UNSPEC && XINT (x, 1) == UNSPEC_LTREF)
    {
      rtx sym = XVECEXP (x, 0, 0);
      gcc_assert (GET_CODE (sym) == SYMBOL_REF
                  && CONSTANT_POOL_ADDRESS_P (sym));

      if (*ref == NULL_RTX)
        *ref = sym;
      else
        gcc_assert (*ref == sym);

      return;
    }

  fmt = GET_RTX_FORMAT (GET_CODE (x));
  for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--)
    {
      if (fmt[i] == 'e')
        {
          find_constant_pool_ref (XEXP (x, i), ref);
        }
      else if (fmt[i] == 'E')
        {
          for (j = 0; j < XVECLEN (x, i); j++)
            find_constant_pool_ref (XVECEXP (x, i, j), ref);
        }
    }
}

/* Replace every reference to the annotated literal pool
   symbol REF in X by its base plus OFFSET.  */

static void
replace_constant_pool_ref (rtx *x, rtx ref, rtx offset)
{
  int i, j;
  const char *fmt;

  gcc_assert (*x != ref);

  if (GET_CODE (*x) == UNSPEC
      && XINT (*x, 1) == UNSPEC_LTREF
      && XVECEXP (*x, 0, 0) == ref)
    {
      *x = gen_rtx_PLUS (Pmode, XVECEXP (*x, 0, 1), offset);
      return;
    }

  if (GET_CODE (*x) == PLUS
      && GET_CODE (XEXP (*x, 1)) == CONST_INT
      && GET_CODE (XEXP (*x, 0)) == UNSPEC
      && XINT (XEXP (*x, 0), 1) == UNSPEC_LTREF
      && XVECEXP (XEXP (*x, 0), 0, 0) == ref)
    {
      rtx addr = gen_rtx_PLUS (Pmode, XVECEXP (XEXP (*x, 0), 0, 1), offset);
      *x = plus_constant (Pmode, addr, INTVAL (XEXP (*x, 1)));
      return;
    }

  fmt = GET_RTX_FORMAT (GET_CODE (*x));
  for (i = GET_RTX_LENGTH (GET_CODE (*x)) - 1; i >= 0; i--)
    {
      if (fmt[i] == 'e')
        {
          replace_constant_pool_ref (&XEXP (*x, i), ref, offset);
        }
      else if (fmt[i] == 'E')
        {
          for (j = 0; j < XVECLEN (*x, i); j++)
            replace_constant_pool_ref (&XVECEXP (*x, i, j), ref, offset);
        }
    }
}

/* Check whether X contains an UNSPEC_LTREL_BASE.
   Return its constant pool symbol if found, NULL_RTX otherwise.  */

static rtx
find_ltrel_base (rtx x)
{
  int i, j;
  const char *fmt;

  if (GET_CODE (x) == UNSPEC
      && XINT (x, 1) == UNSPEC_LTREL_BASE)
    return XVECEXP (x, 0, 0);

  fmt = GET_RTX_FORMAT (GET_CODE (x));
  for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--)
    {
      if (fmt[i] == 'e')
        {
          rtx fnd = find_ltrel_base (XEXP (x, i));
          if (fnd)
            return fnd;
        }
      else if (fmt[i] == 'E')
        {
          for (j = 0; j < XVECLEN (x, i); j++)
            {
              rtx fnd = find_ltrel_base (XVECEXP (x, i, j));
              if (fnd)
                return fnd;
            }
        }
    }

  return NULL_RTX;
}

/* Replace any occurrence of UNSPEC_LTREL_BASE in X with its base.  */

static void
replace_ltrel_base (rtx *x)
{
  int i, j;
  const char *fmt;

  if (GET_CODE (*x) == UNSPEC
      && XINT (*x, 1) == UNSPEC_LTREL_BASE)
    {
      *x = XVECEXP (*x, 0, 1);
      return;
    }

  fmt = GET_RTX_FORMAT (GET_CODE (*x));
  for (i = GET_RTX_LENGTH (GET_CODE (*x)) - 1; i >= 0; i--)
    {
      if (fmt[i] == 'e')
        {
          replace_ltrel_base (&XEXP (*x, i));
        }
      else if (fmt[i] == 'E')
        {
          for (j = 0; j < XVECLEN (*x, i); j++)
            replace_ltrel_base (&XVECEXP (*x, i, j));
        }
    }
}


/* We keep a list of constants which we have to add to internal
   constant tables in the middle of large functions.  */

#define NR_C_MODES 11
machine_mode constant_modes[NR_C_MODES] =
{
  TFmode, TImode, TDmode,
  DFmode, DImode, DDmode,
  SFmode, SImode, SDmode,
  HImode,
  QImode
};

struct constant
{
  struct constant *next;
  rtx value;
  rtx_code_label *label;
};

struct constant_pool
{
  struct constant_pool *next;
  rtx_insn *first_insn;
  rtx_insn *pool_insn;
  bitmap insns;
  rtx_insn *emit_pool_after;

  struct constant *constants[NR_C_MODES];
  struct constant *execute;
  rtx_code_label *label;
  int size;
};

/* Allocate new constant_pool structure.  */

static struct constant_pool *
s390_alloc_pool (void)
{
  struct constant_pool *pool;
  int i;

  pool = (struct constant_pool *) xmalloc (sizeof *pool);
  pool->next = NULL;
  for (i = 0; i < NR_C_MODES; i++)
    pool->constants[i] = NULL;

  pool->execute = NULL;
  pool->label = gen_label_rtx ();
  pool->first_insn = NULL;
  pool->pool_insn = NULL;
  pool->insns = BITMAP_ALLOC (NULL);
  pool->size = 0;
  pool->emit_pool_after = NULL;

  return pool;
}

/* Create new constant pool covering instructions starting at INSN
   and chain it to the end of POOL_LIST.  */

static struct constant_pool *
s390_start_pool (struct constant_pool **pool_list, rtx_insn *insn)
{
  struct constant_pool *pool, **prev;

  pool = s390_alloc_pool ();
  pool->first_insn = insn;

  for (prev = pool_list; *prev; prev = &(*prev)->next)
    ;
  *prev = pool;

  return pool;
}

/* End range of instructions covered by POOL at INSN and emit
   placeholder insn representing the pool.  */

static void
s390_end_pool (struct constant_pool *pool, rtx_insn *insn)
{
  rtx pool_size = GEN_INT (pool->size + 8 /* alignment slop */);

  if (!insn)
    insn = get_last_insn ();

  pool->pool_insn = emit_insn_after (gen_pool (pool_size), insn);
  INSN_ADDRESSES_NEW (pool->pool_insn, -1);
}

/* Add INSN to the list of insns covered by POOL.  */

static void
s390_add_pool_insn (struct constant_pool *pool, rtx insn)
{
  bitmap_set_bit (pool->insns, INSN_UID (insn));
}

/* Return pool out of POOL_LIST that covers INSN.  */

static struct constant_pool *
s390_find_pool (struct constant_pool *pool_list, rtx insn)
{
  struct constant_pool *pool;

  for (pool = pool_list; pool; pool = pool->next)
    if (bitmap_bit_p (pool->insns, INSN_UID (insn)))
      break;

  return pool;
}

/* Add constant VAL of mode MODE to the constant pool POOL.  */

static void
s390_add_constant (struct constant_pool *pool, rtx val, machine_mode mode)
{
  struct constant *c;
  int i;

  for (i = 0; i < NR_C_MODES; i++)
    if (constant_modes[i] == mode)
      break;
  gcc_assert (i != NR_C_MODES);

  for (c = pool->constants[i]; c != NULL; c = c->next)
    if (rtx_equal_p (val, c->value))
      break;

  if (c == NULL)
    {
      c = (struct constant *) xmalloc (sizeof *c);
      c->value = val;
      c->label = gen_label_rtx ();
      c->next = pool->constants[i];
      pool->constants[i] = c;
      pool->size += GET_MODE_SIZE (mode);
    }
}

/* Return an rtx that represents the offset of X from the start of
   pool POOL.  */

static rtx
s390_pool_offset (struct constant_pool *pool, rtx x)
{
  rtx label;

  label = gen_rtx_LABEL_REF (GET_MODE (x), pool->label);
  x = gen_rtx_UNSPEC (GET_MODE (x), gen_rtvec (2, x, label),
                      UNSPEC_POOL_OFFSET);
  return gen_rtx_CONST (GET_MODE (x), x);
}

/* Find constant VAL of mode MODE in the constant pool POOL.
   Return an RTX describing the distance from the start of
   the pool to the location of the new constant.  */

static rtx
s390_find_constant (struct constant_pool *pool, rtx val,
                    machine_mode mode)
{
  struct constant *c;
  int i;

  for (i = 0; i < NR_C_MODES; i++)
    if (constant_modes[i] == mode)
      break;
  gcc_assert (i != NR_C_MODES);

  for (c = pool->constants[i]; c != NULL; c = c->next)
    if (rtx_equal_p (val, c->value))
      break;

  gcc_assert (c);

  return s390_pool_offset (pool, gen_rtx_LABEL_REF (Pmode, c->label));
}

/* Check whether INSN is an execute.  Return the label_ref to its
   execute target template if so, NULL_RTX otherwise.  */

static rtx
s390_execute_label (rtx insn)
{
  if (NONJUMP_INSN_P (insn)
      && GET_CODE (PATTERN (insn)) == PARALLEL
      && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == UNSPEC
      && XINT (XVECEXP (PATTERN (insn), 0, 0), 1) == UNSPEC_EXECUTE)
    return XVECEXP (XVECEXP (PATTERN (insn), 0, 0), 0, 2);

  return NULL_RTX;
}

/* Add execute target for INSN to the constant pool POOL.  */

static void
s390_add_execute (struct constant_pool *pool, rtx insn)
{
  struct constant *c;

  for (c = pool->execute; c != NULL; c = c->next)
    if (INSN_UID (insn) == INSN_UID (c->value))
      break;

  if (c == NULL)
    {
      c = (struct constant *) xmalloc (sizeof *c);
      c->value = insn;
      c->label = gen_label_rtx ();
      c->next = pool->execute;
      pool->execute = c;
      pool->size += 6;
    }
}

/* Find execute target for INSN in the constant pool POOL.
   Return an RTX describing the distance from the start of
   the pool to the location of the execute target.  */

static rtx
s390_find_execute (struct constant_pool *pool, rtx insn)
{
  struct constant *c;

  for (c = pool->execute; c != NULL; c = c->next)
    if (INSN_UID (insn) == INSN_UID (c->value))
      break;

  gcc_assert (c);

  return s390_pool_offset (pool, gen_rtx_LABEL_REF (Pmode, c->label));
}

/* For an execute INSN, extract the execute target template.  */

static rtx
s390_execute_target (rtx insn)
{
  rtx pattern = PATTERN (insn);
  gcc_assert (s390_execute_label (insn));

  if (XVECLEN (pattern, 0) == 2)
    {
      pattern = copy_rtx (XVECEXP (pattern, 0, 1));
    }
  else
    {
      rtvec vec = rtvec_alloc (XVECLEN (pattern, 0) - 1);
      int i;

      for (i = 0; i < XVECLEN (pattern, 0) - 1; i++)
        RTVEC_ELT (vec, i) = copy_rtx (XVECEXP (pattern, 0, i + 1));

      pattern = gen_rtx_PARALLEL (VOIDmode, vec);
    }

  return pattern;
}

/* Indicate that INSN cannot be duplicated.  This is the case for
   execute insns that carry a unique label.  */

static bool
s390_cannot_copy_insn_p (rtx_insn *insn)
{
  rtx label = s390_execute_label (insn);
  return label && label != const0_rtx;
}

/* Dump out the constants in POOL.  If REMOTE_LABEL is true,
   do not emit the pool base label.  */

static void
s390_dump_pool (struct constant_pool *pool, bool remote_label)
{
  struct constant *c;
  rtx_insn *insn = pool->pool_insn;
  int i;

  /* Switch to rodata section.  */
  if (TARGET_CPU_ZARCH)
    {
      insn = emit_insn_after (gen_pool_section_start (), insn);
      INSN_ADDRESSES_NEW (insn, -1);
    }

  /* Ensure minimum pool alignment.  */
  if (TARGET_CPU_ZARCH)
    insn = emit_insn_after (gen_pool_align (GEN_INT (8)), insn);
  else
    insn = emit_insn_after (gen_pool_align (GEN_INT (4)), insn);
  INSN_ADDRESSES_NEW (insn, -1);

  /* Emit pool base label.  */
  if (!remote_label)
    {
      insn = emit_label_after (pool->label, insn);
      INSN_ADDRESSES_NEW (insn, -1);
    }

  /* Dump constants in descending alignment requirement order,
     ensuring proper alignment for every constant.  */
  for (i = 0; i < NR_C_MODES; i++)
    for (c = pool->constants[i]; c; c = c->next)
      {
        /* Convert UNSPEC_LTREL_OFFSET unspecs to pool-relative references.  */
        rtx value = copy_rtx (c->value);
        if (GET_CODE (value) == CONST
            && GET_CODE (XEXP (value, 0)) == UNSPEC
            && XINT (XEXP (value, 0), 1) == UNSPEC_LTREL_OFFSET
            && XVECLEN (XEXP (value, 0), 0) == 1)
          value = s390_pool_offset (pool, XVECEXP (XEXP (value, 0), 0, 0));

        insn = emit_label_after (c->label, insn);
        INSN_ADDRESSES_NEW (insn, -1);

        value = gen_rtx_UNSPEC_VOLATILE (constant_modes[i],
                                         gen_rtvec (1, value),
                                         UNSPECV_POOL_ENTRY);
        insn = emit_insn_after (value, insn);
        INSN_ADDRESSES_NEW (insn, -1);
      }

  /* Ensure minimum alignment for instructions.  */
  insn = emit_insn_after (gen_pool_align (GEN_INT (2)), insn);
  INSN_ADDRESSES_NEW (insn, -1);

  /* Output in-pool execute template insns.  */
  for (c = pool->execute; c; c = c->next)
    {
      insn = emit_label_after (c->label, insn);
      INSN_ADDRESSES_NEW (insn, -1);

      insn = emit_insn_after (s390_execute_target (c->value), insn);
      INSN_ADDRESSES_NEW (insn, -1);
    }

  /* Switch back to previous section.  */
  if (TARGET_CPU_ZARCH)
    {
      insn = emit_insn_after (gen_pool_section_end (), insn);
      INSN_ADDRESSES_NEW (insn, -1);
    }

  insn = emit_barrier_after (insn);
  INSN_ADDRESSES_NEW (insn, -1);

  /* Remove placeholder insn.  */
  remove_insn (pool->pool_insn);
}

/* Free all memory used by POOL.  */

static void
s390_free_pool (struct constant_pool *pool)
{
  struct constant *c, *next;
  int i;

  for (i = 0; i < NR_C_MODES; i++)
    for (c = pool->constants[i]; c; c = next)
      {
        next = c->next;
        free (c);
      }

  for (c = pool->execute; c; c = next)
    {
      next = c->next;
      free (c);
    }

  BITMAP_FREE (pool->insns);
  free (pool);
}


/* Collect main literal pool.  Return NULL on overflow.  */

static struct constant_pool *
s390_mainpool_start (void)
{
  struct constant_pool *pool;
  rtx_insn *insn;

  pool = s390_alloc_pool ();

  for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
    {
      if (NONJUMP_INSN_P (insn)
          && GET_CODE (PATTERN (insn)) == SET
          && GET_CODE (SET_SRC (PATTERN (insn))) == UNSPEC_VOLATILE
          && XINT (SET_SRC (PATTERN (insn)), 1) == UNSPECV_MAIN_POOL)
        {
          /* There might be two main_pool instructions if base_reg
             is call-clobbered; one for shrink-wrapped code and one
             for the rest.  We want to keep the first.  */
          if (pool->pool_insn)
            {
              insn = PREV_INSN (insn);
              delete_insn (NEXT_INSN (insn));
              continue;
            }
          pool->pool_insn = insn;
        }

      if (!TARGET_CPU_ZARCH && s390_execute_label (insn))
        {
          s390_add_execute (pool, insn);
        }
      else if (NONJUMP_INSN_P (insn) || CALL_P (insn))
        {
          rtx pool_ref = NULL_RTX;
          find_constant_pool_ref (PATTERN (insn), &pool_ref);
          if (pool_ref)
            {
              rtx constant = get_pool_constant (pool_ref);
              machine_mode mode = get_pool_mode (pool_ref);
              s390_add_constant (pool, constant, mode);
            }
        }

      /* If hot/cold partitioning is enabled we have to make sure that
         the literal pool is emitted in the same section where the
         initialization of the literal pool base pointer takes place.
         emit_pool_after is only used in the non-overflow case on non
         Z cpus where we can emit the literal pool at the end of the
         function body within the text section.  */
      if (NOTE_P (insn)
          && NOTE_KIND (insn) == NOTE_INSN_SWITCH_TEXT_SECTIONS
          && !pool->emit_pool_after)
        pool->emit_pool_after = PREV_INSN (insn);
    }

  gcc_assert (pool->pool_insn || pool->size == 0);

  if (pool->size >= 4096)
    {
      /* We're going to chunkify the pool, so remove the main
         pool placeholder insn.  */
      remove_insn (pool->pool_insn);

      s390_free_pool (pool);
      pool = NULL;
    }

  /* If the functions ends with the section where the literal pool
     should be emitted set the marker to its end.  */
  if (pool && !pool->emit_pool_after)
    pool->emit_pool_after = get_last_insn ();

  return pool;
}

/* POOL holds the main literal pool as collected by s390_mainpool_start.
   Modify the current function to output the pool constants as well as
   the pool register setup instruction.  */

static void
s390_mainpool_finish (struct constant_pool *pool)
{
  rtx base_reg = cfun->machine->base_reg;

  /* If the pool is empty, we're done.  */
  if (pool->size == 0)
    {
      /* We don't actually need a base register after all.  */
      cfun->machine->base_reg = NULL_RTX;

      if (pool->pool_insn)
        remove_insn (pool->pool_insn);
      s390_free_pool (pool);
      return;
    }

  /* We need correct insn addresses.  */
  shorten_branches (get_insns ());

  /* On zSeries, we use a LARL to load the pool register.  The pool is
     located in the .rodata section, so we emit it after the function.  */
  if (TARGET_CPU_ZARCH)
    {
      rtx set = gen_main_base_64 (base_reg, pool->label);
      rtx_insn *insn = emit_insn_after (set, pool->pool_insn);
      INSN_ADDRESSES_NEW (insn, -1);
      remove_insn (pool->pool_insn);

      insn = get_last_insn ();
      pool->pool_insn = emit_insn_after (gen_pool (const0_rtx), insn);
      INSN_ADDRESSES_NEW (pool->pool_insn, -1);

      s390_dump_pool (pool, 0);
    }

  /* On S/390, if the total size of the function's code plus literal pool
     does not exceed 4096 bytes, we use BASR to set up a function base
     pointer, and emit the literal pool at the end of the function.  */
  else if (INSN_ADDRESSES (INSN_UID (pool->emit_pool_after))
           + pool->size + 8 /* alignment slop */ < 4096)
    {
      rtx set = gen_main_base_31_small (base_reg, pool->label);
      rtx_insn *insn = emit_insn_after (set, pool->pool_insn);
      INSN_ADDRESSES_NEW (insn, -1);
      remove_insn (pool->pool_insn);

      insn = emit_label_after (pool->label, insn);
      INSN_ADDRESSES_NEW (insn, -1);

      /* emit_pool_after will be set by s390_mainpool_start to the
         last insn of the section where the literal pool should be
         emitted.  */
      insn = pool->emit_pool_after;

      pool->pool_insn = emit_insn_after (gen_pool (const0_rtx), insn);
      INSN_ADDRESSES_NEW (pool->pool_insn, -1);

      s390_dump_pool (pool, 1);
    }

  /* Otherwise, we emit an inline literal pool and use BASR to branch
     over it, setting up the pool register at the same time.  */
  else
    {
      rtx_code_label *pool_end = gen_label_rtx ();

      rtx pat = gen_main_base_31_large (base_reg, pool->label, pool_end);
      rtx_insn *insn = emit_jump_insn_after (pat, pool->pool_insn);
      JUMP_LABEL (insn) = pool_end;
      INSN_ADDRESSES_NEW (insn, -1);
      remove_insn (pool->pool_insn);

      insn = emit_label_after (pool->label, insn);
      INSN_ADDRESSES_NEW (insn, -1);

      pool->pool_insn = emit_insn_after (gen_pool (const0_rtx), insn);
      INSN_ADDRESSES_NEW (pool->pool_insn, -1);

      insn = emit_label_after (pool_end, pool->pool_insn);
      INSN_ADDRESSES_NEW (insn, -1);

      s390_dump_pool (pool, 1);
    }


  /* Replace all literal pool references.  */

  for (rtx_insn *insn = get_insns (); insn; insn = NEXT_INSN (insn))
    {
      if (INSN_P (insn))
        replace_ltrel_base (&PATTERN (insn));

      if (NONJUMP_INSN_P (insn) || CALL_P (insn))
        {
          rtx addr, pool_ref = NULL_RTX;
          find_constant_pool_ref (PATTERN (insn), &pool_ref);
          if (pool_ref)
            {
              if (s390_execute_label (insn))
                addr = s390_find_execute (pool, insn);
              else
                addr = s390_find_constant (pool, get_pool_constant (pool_ref),
                                                 get_pool_mode (pool_ref));

              replace_constant_pool_ref (&PATTERN (insn), pool_ref, addr);
              INSN_CODE (insn) = -1;
            }
        }
    }


  /* Free the pool.  */
  s390_free_pool (pool);
}

/* POOL holds the main literal pool as collected by s390_mainpool_start.
   We have decided we cannot use this pool, so revert all changes
   to the current function that were done by s390_mainpool_start.  */
static void
s390_mainpool_cancel (struct constant_pool *pool)
{
  /* We didn't actually change the instruction stream, so simply
     free the pool memory.  */
  s390_free_pool (pool);
}


/* Chunkify the literal pool.  */

#define S390_POOL_CHUNK_MIN     0xc00
#define S390_POOL_CHUNK_MAX     0xe00

static struct constant_pool *
s390_chunkify_start (void)
{
  struct constant_pool *curr_pool = NULL, *pool_list = NULL;
  int extra_size = 0;
  bitmap far_labels;
  rtx pending_ltrel = NULL_RTX;
  rtx_insn *insn;

  rtx (*gen_reload_base) (rtx, rtx) =
    TARGET_CPU_ZARCH? gen_reload_base_64 : gen_reload_base_31;


  /* We need correct insn addresses.  */

  shorten_branches (get_insns ());

  /* Scan all insns and move literals to pool chunks.  */

  for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
    {
      bool section_switch_p = false;

      /* Check for pending LTREL_BASE.  */
      if (INSN_P (insn))
        {
          rtx ltrel_base = find_ltrel_base (PATTERN (insn));
          if (ltrel_base)
            {
              gcc_assert (ltrel_base == pending_ltrel);
              pending_ltrel = NULL_RTX;
            }
        }

      if (!TARGET_CPU_ZARCH && s390_execute_label (insn))
        {
          if (!curr_pool)
            curr_pool = s390_start_pool (&pool_list, insn);

          s390_add_execute (curr_pool, insn);
          s390_add_pool_insn (curr_pool, insn);
        }
      else if (NONJUMP_INSN_P (insn) || CALL_P (insn))
        {
          rtx pool_ref = NULL_RTX;
          find_constant_pool_ref (PATTERN (insn), &pool_ref);
          if (pool_ref)
            {
              rtx constant = get_pool_constant (pool_ref);
              machine_mode mode = get_pool_mode (pool_ref);

              if (!curr_pool)
                curr_pool = s390_start_pool (&pool_list, insn);

              s390_add_constant (curr_pool, constant, mode);
              s390_add_pool_insn (curr_pool, insn);

              /* Don't split the pool chunk between a LTREL_OFFSET load
                 and the corresponding LTREL_BASE.  */
              if (GET_CODE (constant) == CONST
                  && GET_CODE (XEXP (constant, 0)) == UNSPEC
                  && XINT (XEXP (constant, 0), 1) == UNSPEC_LTREL_OFFSET)
                {
                  gcc_assert (!pending_ltrel);
                  pending_ltrel = pool_ref;
                }
            }
        }

      if (JUMP_P (insn) || JUMP_TABLE_DATA_P (insn) || LABEL_P (insn))
        {
          if (curr_pool)
            s390_add_pool_insn (curr_pool, insn);
          /* An LTREL_BASE must follow within the same basic block.  */
          gcc_assert (!pending_ltrel);
        }

      if (NOTE_P (insn))
        switch (NOTE_KIND (insn))
          {
          case NOTE_INSN_SWITCH_TEXT_SECTIONS:
            section_switch_p = true;
            break;
          case NOTE_INSN_VAR_LOCATION:
          case NOTE_INSN_CALL_ARG_LOCATION:
            continue;
          default:
            break;
          }

      if (!curr_pool
          || INSN_ADDRESSES_SIZE () <= (size_t) INSN_UID (insn)
          || INSN_ADDRESSES (INSN_UID (insn)) == -1)
        continue;

      if (TARGET_CPU_ZARCH)
        {
          if (curr_pool->size < S390_POOL_CHUNK_MAX)
            continue;

          s390_end_pool (curr_pool, NULL);
          curr_pool = NULL;
        }
      else
        {
          int chunk_size = INSN_ADDRESSES (INSN_UID (insn))
                           - INSN_ADDRESSES (INSN_UID (curr_pool->first_insn))
                         + extra_size;

          /* We will later have to insert base register reload insns.
             Those will have an effect on code size, which we need to
             consider here.  This calculation makes rather pessimistic
             worst-case assumptions.  */
          if (LABEL_P (insn))
            extra_size += 6;

          if (chunk_size < S390_POOL_CHUNK_MIN
              && curr_pool->size < S390_POOL_CHUNK_MIN
              && !section_switch_p)
            continue;

          /* Pool chunks can only be inserted after BARRIERs ...  */
          if (BARRIER_P (insn))
            {
              s390_end_pool (curr_pool, insn);
              curr_pool = NULL;
              extra_size = 0;
            }

          /* ... so if we don't find one in time, create one.  */
          else if (chunk_size > S390_POOL_CHUNK_MAX
                   || curr_pool->size > S390_POOL_CHUNK_MAX
                   || section_switch_p)
            {
              rtx_insn *label, *jump, *barrier, *next, *prev;

              if (!section_switch_p)
                {
                  /* We can insert the barrier only after a 'real' insn.  */
                  if (! NONJUMP_INSN_P (insn) && ! CALL_P (insn))
                    continue;
                  if (get_attr_length (insn) == 0)
                    continue;
                  /* Don't separate LTREL_BASE from the corresponding
                     LTREL_OFFSET load.  */
                  if (pending_ltrel)
                    continue;
                  next = insn;
                  do
                    {
                      insn = next;
                      next = NEXT_INSN (insn);
                    }
                  while (next
                         && NOTE_P (next)
                         && (NOTE_KIND (next) == NOTE_INSN_VAR_LOCATION
                             || NOTE_KIND (next) == NOTE_INSN_CALL_ARG_LOCATION));
                }
              else
                {
                  gcc_assert (!pending_ltrel);

                  /* The old pool has to end before the section switch
                     note in order to make it part of the current
                     section.  */
                  insn = PREV_INSN (insn);
                }

              label = gen_label_rtx ();
              prev = insn;
              if (prev && NOTE_P (prev))
                prev = prev_nonnote_insn (prev);
              if (prev)
                jump = emit_jump_insn_after_setloc (gen_jump (label), insn,
                                                    INSN_LOCATION (prev));
              else
                jump = emit_jump_insn_after_noloc (gen_jump (label), insn);
              barrier = emit_barrier_after (jump);
              insn = emit_label_after (label, barrier);
              JUMP_LABEL (jump) = label;
              LABEL_NUSES (label) = 1;

              INSN_ADDRESSES_NEW (jump, -1);
              INSN_ADDRESSES_NEW (barrier, -1);
              INSN_ADDRESSES_NEW (insn, -1);

              s390_end_pool (curr_pool, barrier);
              curr_pool = NULL;
              extra_size = 0;
            }
        }
    }

  if (curr_pool)
    s390_end_pool (curr_pool, NULL);
  gcc_assert (!pending_ltrel);

  /* Find all labels that are branched into
     from an insn belonging to a different chunk.  */

  far_labels = BITMAP_ALLOC (NULL);

  for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
    {
      rtx_jump_table_data *table;

      /* Labels marked with LABEL_PRESERVE_P can be target
         of non-local jumps, so we have to mark them.
         The same holds for named labels.

         Don't do that, however, if it is the label before
         a jump table.  */

      if (LABEL_P (insn)
          && (LABEL_PRESERVE_P (insn) || LABEL_NAME (insn)))
        {
          rtx_insn *vec_insn = NEXT_INSN (insn);
          if (! vec_insn || ! JUMP_TABLE_DATA_P (vec_insn))
            bitmap_set_bit (far_labels, CODE_LABEL_NUMBER (insn));
        }
      /* Check potential targets in a table jump (casesi_jump).  */
      else if (tablejump_p (insn, NULL, &table))
        {
          rtx vec_pat = PATTERN (table);
          int i, diff_p = GET_CODE (vec_pat) == ADDR_DIFF_VEC;

          for (i = 0; i < XVECLEN (vec_pat, diff_p); i++)
            {
              rtx label = XEXP (XVECEXP (vec_pat, diff_p, i), 0);

              if (s390_find_pool (pool_list, label)
                  != s390_find_pool (pool_list, insn))
                bitmap_set_bit (far_labels, CODE_LABEL_NUMBER (label));
            }
        }
      /* If we have a direct jump (conditional or unconditional),
         check all potential targets.  */
      else if (JUMP_P (insn))
        {
          rtx pat = PATTERN (insn);

          if (GET_CODE (pat) == PARALLEL)
            pat = XVECEXP (pat, 0, 0);

          if (GET_CODE (pat) == SET)
            {
              rtx label = JUMP_LABEL (insn);
              if (label && !ANY_RETURN_P (label))
                {
                  if (s390_find_pool (pool_list, label)
                      != s390_find_pool (pool_list, insn))
                    bitmap_set_bit (far_labels, CODE_LABEL_NUMBER (label));
                }
            }
        }
    }

  /* Insert base register reload insns before every pool.  */

  for (curr_pool = pool_list; curr_pool; curr_pool = curr_pool->next)
    {
      rtx new_insn = gen_reload_base (cfun->machine->base_reg,
                                      curr_pool->label);
      rtx_insn *insn = curr_pool->first_insn;
      INSN_ADDRESSES_NEW (emit_insn_before (new_insn, insn), -1);
    }

  /* Insert base register reload insns at every far label.  */

  for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
    if (LABEL_P (insn)
        && bitmap_bit_p (far_labels, CODE_LABEL_NUMBER (insn)))
      {
        struct constant_pool *pool = s390_find_pool (pool_list, insn);
        if (pool)
          {
            rtx new_insn = gen_reload_base (cfun->machine->base_reg,
                                            pool->label);
            INSN_ADDRESSES_NEW (emit_insn_after (new_insn, insn), -1);
          }
      }


  BITMAP_FREE (far_labels);


  /* Recompute insn addresses.  */

  init_insn_lengths ();
  shorten_branches (get_insns ());

  return pool_list;
}

/* POOL_LIST is a chunk list as prepared by s390_chunkify_start.
   After we have decided to use this list, finish implementing
   all changes to the current function as required.  */

static void
s390_chunkify_finish (struct constant_pool *pool_list)
{
  struct constant_pool *curr_pool = NULL;
  rtx_insn *insn;


  /* Replace all literal pool references.  */

  for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
    {
      if (INSN_P (insn))
        replace_ltrel_base (&PATTERN (insn));

      curr_pool = s390_find_pool (pool_list, insn);
      if (!curr_pool)
        continue;

      if (NONJUMP_INSN_P (insn) || CALL_P (insn))
        {
          rtx addr, pool_ref = NULL_RTX;
          find_constant_pool_ref (PATTERN (insn), &pool_ref);
          if (pool_ref)
            {
              if (s390_execute_label (insn))
                addr = s390_find_execute (curr_pool, insn);
              else
                addr = s390_find_constant (curr_pool,
                                           get_pool_constant (pool_ref),
                                           get_pool_mode (pool_ref));

              replace_constant_pool_ref (&PATTERN (insn), pool_ref, addr);
              INSN_CODE (insn) = -1;
            }
        }
    }

  /* Dump out all literal pools.  */

  for (curr_pool = pool_list; curr_pool; curr_pool = curr_pool->next)
    s390_dump_pool (curr_pool, 0);

  /* Free pool list.  */

  while (pool_list)
    {
      struct constant_pool *next = pool_list->next;
      s390_free_pool (pool_list);
      pool_list = next;
    }
}

/* POOL_LIST is a chunk list as prepared by s390_chunkify_start.
   We have decided we cannot use this list, so revert all changes
   to the current function that were done by s390_chunkify_start.  */

static void
s390_chunkify_cancel (struct constant_pool *pool_list)
{
  struct constant_pool *curr_pool = NULL;
  rtx_insn *insn;

  /* Remove all pool placeholder insns.  */

  for (curr_pool = pool_list; curr_pool; curr_pool = curr_pool->next)
    {
      /* Did we insert an extra barrier?  Remove it.  */
      rtx_insn *barrier = PREV_INSN (curr_pool->pool_insn);
      rtx_insn *jump = barrier? PREV_INSN (barrier) : NULL;
      rtx_insn *label = NEXT_INSN (curr_pool->pool_insn);

      if (jump && JUMP_P (jump)
          && barrier && BARRIER_P (barrier)
          && label && LABEL_P (label)
          && GET_CODE (PATTERN (jump)) == SET
          && SET_DEST (PATTERN (jump)) == pc_rtx
          && GET_CODE (SET_SRC (PATTERN (jump))) == LABEL_REF
          && XEXP (SET_SRC (PATTERN (jump)), 0) == label)
        {
          remove_insn (jump);
          remove_insn (barrier);
          remove_insn (label);
        }

      remove_insn (curr_pool->pool_insn);
    }

  /* Remove all base register reload insns.  */

  for (insn = get_insns (); insn; )
    {
      rtx_insn *next_insn = NEXT_INSN (insn);

      if (NONJUMP_INSN_P (insn)
          && GET_CODE (PATTERN (insn)) == SET
          && GET_CODE (SET_SRC (PATTERN (insn))) == UNSPEC
          && XINT (SET_SRC (PATTERN (insn)), 1) == UNSPEC_RELOAD_BASE)
        remove_insn (insn);

      insn = next_insn;
    }

  /* Free pool list.  */

  while (pool_list)
    {
      struct constant_pool *next = pool_list->next;
      s390_free_pool (pool_list);
      pool_list = next;
    }
}

/* Output the constant pool entry EXP in mode MODE with alignment ALIGN.  */

void
s390_output_pool_entry (rtx exp, machine_mode mode, unsigned int align)
{
  REAL_VALUE_TYPE r;

  switch (GET_MODE_CLASS (mode))
    {
    case MODE_FLOAT:
    case MODE_DECIMAL_FLOAT:
      gcc_assert (GET_CODE (exp) == CONST_DOUBLE);

      REAL_VALUE_FROM_CONST_DOUBLE (r, exp);
      assemble_real (r, mode, align);
      break;

    case MODE_INT:
      assemble_integer (exp, GET_MODE_SIZE (mode), align, 1);
      mark_symbol_refs_as_used (exp);
      break;

    default:
      gcc_unreachable ();
    }
}


/* Return an RTL expression representing the value of the return address
   for the frame COUNT steps up from the current frame.  FRAME is the
   frame pointer of that frame.  */

rtx
s390_return_addr_rtx (int count, rtx frame ATTRIBUTE_UNUSED)
{
  int offset;
  rtx addr;

  /* Without backchain, we fail for all but the current frame.  */

  if (!TARGET_BACKCHAIN && count > 0)
    return NULL_RTX;

  /* For the current frame, we need to make sure the initial
     value of RETURN_REGNUM is actually saved.  */

  if (count == 0)
    {
      /* On non-z architectures branch splitting could overwrite r14.  */
      if (TARGET_CPU_ZARCH)
        return get_hard_reg_initial_val (Pmode, RETURN_REGNUM);
      else
        {
          cfun_frame_layout.save_return_addr_p = true;
          return gen_rtx_MEM (Pmode, return_address_pointer_rtx);
        }
    }

  if (TARGET_PACKED_STACK)
    offset = -2 * UNITS_PER_LONG;
  else
    offset = RETURN_REGNUM * UNITS_PER_LONG;

  addr = plus_constant (Pmode, frame, offset);
  addr = memory_address (Pmode, addr);
  return gen_rtx_MEM (Pmode, addr);
}

/* Return an RTL expression representing the back chain stored in
   the current stack frame.  */

rtx
s390_back_chain_rtx (void)
{
  rtx chain;

  gcc_assert (TARGET_BACKCHAIN);

  if (TARGET_PACKED_STACK)
    chain = plus_constant (Pmode, stack_pointer_rtx,
                           STACK_POINTER_OFFSET - UNITS_PER_LONG);
  else
    chain = stack_pointer_rtx;

  chain = gen_rtx_MEM (Pmode, chain);
  return chain;
}

/* Find first call clobbered register unused in a function.
   This could be used as base register in a leaf function
   or for holding the return address before epilogue.  */

static int
find_unused_clobbered_reg (void)
{
  int i;
  for (i = 0; i < 6; i++)
    if (!df_regs_ever_live_p (i))
      return i;
  return 0;
}


/* Helper function for s390_regs_ever_clobbered.  Sets the fields in DATA for all
   clobbered hard regs in SETREG.  */

static void
s390_reg_clobbered_rtx (rtx setreg, const_rtx set_insn ATTRIBUTE_UNUSED, void *data)
{
  char *regs_ever_clobbered = (char *)data;
  unsigned int i, regno;
  machine_mode mode = GET_MODE (setreg);

  if (GET_CODE (setreg) == SUBREG)
    {
      rtx inner = SUBREG_REG (setreg);
      if (!GENERAL_REG_P (inner) && !FP_REG_P (inner))
        return;
      regno = subreg_regno (setreg);
    }
  else if (GENERAL_REG_P (setreg) || FP_REG_P (setreg))
    regno = REGNO (setreg);
  else
    return;

  for (i = regno;
       i < regno + HARD_REGNO_NREGS (regno, mode);
       i++)
    regs_ever_clobbered[i] = 1;
}

/* Walks through all basic blocks of the current function looking
   for clobbered hard regs using s390_reg_clobbered_rtx.  The fields
   of the passed integer array REGS_EVER_CLOBBERED are set to one for
   each of those regs.  */

static void
s390_regs_ever_clobbered (char regs_ever_clobbered[])
{
  basic_block cur_bb;
  rtx_insn *cur_insn;
  unsigned int i;

  memset (regs_ever_clobbered, 0, 32);

  /* For non-leaf functions we have to consider all call clobbered regs to be
     clobbered.  */
  if (!crtl->is_leaf)
    {
      for (i = 0; i < 32; i++)
        regs_ever_clobbered[i] = call_really_used_regs[i];
    }

  /* Make the "magic" eh_return registers live if necessary.  For regs_ever_live
     this work is done by liveness analysis (mark_regs_live_at_end).
     Special care is needed for functions containing landing pads.  Landing pads
     may use the eh registers, but the code which sets these registers is not
     contained in that function.  Hence s390_regs_ever_clobbered is not able to
     deal with this automatically.  */
  if (crtl->calls_eh_return || cfun->machine->has_landing_pad_p)
    for (i = 0; EH_RETURN_DATA_REGNO (i) != INVALID_REGNUM ; i++)
      if (crtl->calls_eh_return
          || (cfun->machine->has_landing_pad_p
              && df_regs_ever_live_p (EH_RETURN_DATA_REGNO (i))))
        regs_ever_clobbered[EH_RETURN_DATA_REGNO (i)] = 1;

  /* For nonlocal gotos all call-saved registers have to be saved.
     This flag is also set for the unwinding code in libgcc.
     See expand_builtin_unwind_init.  For regs_ever_live this is done by
     reload.  */
  if (crtl->saves_all_registers)
    for (i = 0; i < 32; i++)
      if (!call_really_used_regs[i])
        regs_ever_clobbered[i] = 1;

  FOR_EACH_BB_FN (cur_bb, cfun)
    {
      FOR_BB_INSNS (cur_bb, cur_insn)
        {
          rtx pat;

          if (!INSN_P (cur_insn))
            continue;

          pat = PATTERN (cur_insn);

          /* Ignore GPR restore insns.  */
          if (epilogue_completed && RTX_FRAME_RELATED_P (cur_insn))
            {
              if (GET_CODE (pat) == SET
                  && GENERAL_REG_P (SET_DEST (pat)))
                {
                  /* lgdr  */
                  if (GET_MODE (SET_SRC (pat)) == DImode
                      && FP_REG_P (SET_SRC (pat)))
                    continue;

                  /* l / lg  */
                  if (GET_CODE (SET_SRC (pat)) == MEM)
                    continue;
                }

              /* lm / lmg */
              if (GET_CODE (pat) == PARALLEL
                  && load_multiple_operation (pat, VOIDmode))
                continue;
            }

          note_stores (pat,
                       s390_reg_clobbered_rtx,
                       regs_ever_clobbered);
        }
    }
}

/* Determine the frame area which actually has to be accessed
   in the function epilogue. The values are stored at the
   given pointers AREA_BOTTOM (address of the lowest used stack
   address) and AREA_TOP (address of the first item which does
   not belong to the stack frame).  */

static void
s390_frame_area (int *area_bottom, int *area_top)
{
  int b, t;

  b = INT_MAX;
  t = INT_MIN;

  if (cfun_frame_layout.first_restore_gpr != -1)
    {
      b = (cfun_frame_layout.gprs_offset
           + cfun_frame_layout.first_restore_gpr * UNITS_PER_LONG);
      t = b + (cfun_frame_layout.last_restore_gpr
               - cfun_frame_layout.first_restore_gpr + 1) * UNITS_PER_LONG;
    }

  if (TARGET_64BIT && cfun_save_high_fprs_p)
    {
      b = MIN (b, cfun_frame_layout.f8_offset);
      t = MAX (t, (cfun_frame_layout.f8_offset
                   + cfun_frame_layout.high_fprs * 8));
    }

  if (!TARGET_64BIT)
    {
      if (cfun_fpr_save_p (FPR4_REGNUM))
        {
          b = MIN (b, cfun_frame_layout.f4_offset);
          t = MAX (t, cfun_frame_layout.f4_offset + 8);
        }
      if (cfun_fpr_save_p (FPR6_REGNUM))
        {
          b = MIN (b, cfun_frame_layout.f4_offset + 8);
          t = MAX (t, cfun_frame_layout.f4_offset + 16);
        }
    }
  *area_bottom = b;
  *area_top = t;
}
/* Update gpr_save_slots in the frame layout trying to make use of
   FPRs as GPR save slots.
   This is a helper routine of s390_register_info.  */

static void
s390_register_info_gprtofpr ()
{
  int save_reg_slot = FPR0_REGNUM;
  int i, j;

  if (!TARGET_Z10 || !TARGET_HARD_FLOAT || !crtl->is_leaf)
    return;

  for (i = 15; i >= 6; i--)
    {
      if (cfun_gpr_save_slot (i) == 0)
        continue;

      /* Advance to the next FP register which can be used as a
         GPR save slot.  */
      while ((!call_really_used_regs[save_reg_slot]
              || df_regs_ever_live_p (save_reg_slot)
              || cfun_fpr_save_p (save_reg_slot))
             && FP_REGNO_P (save_reg_slot))
        save_reg_slot++;
      if (!FP_REGNO_P (save_reg_slot))
        {
          /* We only want to use ldgr/lgdr if we can get rid of
             stm/lm entirely.  So undo the gpr slot allocation in
             case we ran out of FPR save slots.  */
          for (j = 6; j <= 15; j++)
            if (FP_REGNO_P (cfun_gpr_save_slot (j)))
              cfun_gpr_save_slot (j) = -1;
          break;
        }
      cfun_gpr_save_slot (i) = save_reg_slot++;
    }
}

/* Set the bits in fpr_bitmap for FPRs which need to be saved due to
   stdarg.
   This is a helper routine for s390_register_info.  */

static void
s390_register_info_stdarg_fpr ()
{
  int i;
  int min_fpr;
  int max_fpr;

  /* Save the FP argument regs for stdarg. f0, f2 for 31 bit and
     f0-f4 for 64 bit.  */
  if (!cfun->stdarg
      || !TARGET_HARD_FLOAT
      || !cfun->va_list_fpr_size
      || crtl->args.info.fprs >= FP_ARG_NUM_REG)
    return;

  min_fpr = crtl->args.info.fprs;
  max_fpr = min_fpr + cfun->va_list_fpr_size;
  if (max_fpr > FP_ARG_NUM_REG)
    max_fpr = FP_ARG_NUM_REG;

  for (i = min_fpr; i < max_fpr; i++)
    cfun_set_fpr_save (i + FPR0_REGNUM);
}

/* Reserve the GPR save slots for GPRs which need to be saved due to
   stdarg.
   This is a helper routine for s390_register_info.  */

static void
s390_register_info_stdarg_gpr ()
{
  int i;
  int min_gpr;
  int max_gpr;

  if (!cfun->stdarg
      || !cfun->va_list_gpr_size
      || crtl->args.info.gprs >= GP_ARG_NUM_REG)
    return;

  min_gpr = crtl->args.info.gprs;
  max_gpr = min_gpr + cfun->va_list_gpr_size;
  if (max_gpr > GP_ARG_NUM_REG)
    max_gpr = GP_ARG_NUM_REG;

  for (i = min_gpr; i < max_gpr; i++)
    cfun_gpr_save_slot (2 + i) = -1;
}

/* The GPR and FPR save slots in cfun->machine->frame_layout are set
   for registers which need to be saved in function prologue.
   This function can be used until the insns emitted for save/restore
   of the regs are visible in the RTL stream.  */

static void
s390_register_info ()
{
  int i, j;
  char clobbered_regs[32];

  gcc_assert (!epilogue_completed);

  if (reload_completed)
    /* After reload we rely on our own routine to determine which
       registers need saving.  */
    s390_regs_ever_clobbered (clobbered_regs);
  else
    /* During reload we use regs_ever_live as a base since reload
       does changes in there which we otherwise would not be aware
       of.  */
    for (i = 0; i < 32; i++)
      clobbered_regs[i] = df_regs_ever_live_p (i);

  for (i = 0; i < 32; i++)
    clobbered_regs[i] = clobbered_regs[i] && !global_regs[i];

  /* Mark the call-saved FPRs which need to be saved.
     This needs to be done before checking the special GPRs since the
     stack pointer usage depends on whether high FPRs have to be saved
     or not.  */
  cfun_frame_layout.fpr_bitmap = 0;
  cfun_frame_layout.high_fprs = 0;
  for (i = FPR0_REGNUM; i <= FPR15_REGNUM; i++)
    if (clobbered_regs[i] && !call_really_used_regs[i])
      {
        cfun_set_fpr_save (i);
        if (i >= FPR8_REGNUM)
          cfun_frame_layout.high_fprs++;
      }

  if (flag_pic)
    clobbered_regs[PIC_OFFSET_TABLE_REGNUM]
      |= !!df_regs_ever_live_p (PIC_OFFSET_TABLE_REGNUM);

  clobbered_regs[BASE_REGNUM]
    |= (cfun->machine->base_reg
        && REGNO (cfun->machine->base_reg) == BASE_REGNUM);

  clobbered_regs[HARD_FRAME_POINTER_REGNUM]
    |= !!frame_pointer_needed;

  /* On pre z900 machines this might take until machine dependent
     reorg to decide.
     save_return_addr_p will only be set on non-zarch machines so
     there is no risk that r14 goes into an FPR instead of a stack
     slot.  */
  clobbered_regs[RETURN_REGNUM]
    |= (!crtl->is_leaf
        || TARGET_TPF_PROFILING
        || cfun->machine->split_branches_pending_p
        || cfun_frame_layout.save_return_addr_p
        || crtl->calls_eh_return);

  clobbered_regs[STACK_POINTER_REGNUM]
    |= (!crtl->is_leaf
        || TARGET_TPF_PROFILING
        || cfun_save_high_fprs_p
        || get_frame_size () > 0
        || (reload_completed && cfun_frame_layout.frame_size > 0)
        || cfun->calls_alloca);

  memset (cfun_frame_layout.gpr_save_slots, 0, 16);

  for (i = 6; i < 16; i++)
    if (clobbered_regs[i])
      cfun_gpr_save_slot (i) = -1;

  s390_register_info_stdarg_fpr ();
  s390_register_info_gprtofpr ();

  /* First find the range of GPRs to be restored.  Vararg regs don't
     need to be restored so we do it before assigning slots to the
     vararg GPRs.  */
  for (i = 0; i < 16 && cfun_gpr_save_slot (i) != -1; i++);
  for (j = 15; j > i && cfun_gpr_save_slot (j) != -1; j--);
  cfun_frame_layout.first_restore_gpr = (i == 16) ? -1 : i;
  cfun_frame_layout.last_restore_gpr = (i == 16) ? -1 : j;

  /* stdarg functions might need to save GPRs 2 to 6.  This might
     override the GPR->FPR save decision made above for r6 since
     vararg regs must go to the stack.  */
  s390_register_info_stdarg_gpr ();

  /* Now the range of GPRs which need saving.  */
  for (i = 0; i < 16 && cfun_gpr_save_slot (i) != -1; i++);
  for (j = 15; j > i && cfun_gpr_save_slot (j) != -1; j--);
  cfun_frame_layout.first_save_gpr = (i == 16) ? -1 : i;
  cfun_frame_layout.last_save_gpr = (i == 16) ? -1 : j;
}

/* This function is called by s390_optimize_prologue in order to get
   rid of unnecessary GPR save/restore instructions.  The register info
   for the GPRs is re-computed and the ranges are re-calculated.  */

static void
s390_optimize_register_info ()
{
  char clobbered_regs[32];
  int i, j;

  gcc_assert (epilogue_completed);
  gcc_assert (!cfun->machine->split_branches_pending_p);

  s390_regs_ever_clobbered (clobbered_regs);

  for (i = 0; i < 32; i++)
    clobbered_regs[i] = clobbered_regs[i] && !global_regs[i];

  /* There is still special treatment needed for cases invisible to
     s390_regs_ever_clobbered.  */
  clobbered_regs[RETURN_REGNUM]
    |= (TARGET_TPF_PROFILING
        /* When expanding builtin_return_addr in ESA mode we do not
           know whether r14 will later be needed as scratch reg when
           doing branch splitting.  So the builtin always accesses the
           r14 save slot and we need to stick to the save/restore
           decision for r14 even if it turns out that it didn't get
           clobbered.  */
        || cfun_frame_layout.save_return_addr_p
        || crtl->calls_eh_return);

  memset (cfun_frame_layout.gpr_save_slots, 0, 6);

  for (i = 6; i < 16; i++)
    if (!clobbered_regs[i])
      cfun_gpr_save_slot (i) = 0;

  for (i = 0; i < 16 && cfun_gpr_save_slot (i) != -1; i++);
  for (j = 15; j > i && cfun_gpr_save_slot (j) != -1; j--);
  cfun_frame_layout.first_restore_gpr = (i == 16) ? -1 : i;
  cfun_frame_layout.last_restore_gpr = (i == 16) ? -1 : j;

  s390_register_info_stdarg_gpr ();

  for (i = 0; i < 16 && cfun_gpr_save_slot (i) != -1; i++);
  for (j = 15; j > i && cfun_gpr_save_slot (j) != -1; j--);
  cfun_frame_layout.first_save_gpr = (i == 16) ? -1 : i;
  cfun_frame_layout.last_save_gpr = (i == 16) ? -1 : j;
}

/* Fill cfun->machine with info about frame of current function.  */

static void
s390_frame_info (void)
{
  HOST_WIDE_INT lowest_offset;

  cfun_frame_layout.first_save_gpr_slot = cfun_frame_layout.first_save_gpr;
  cfun_frame_layout.last_save_gpr_slot = cfun_frame_layout.last_save_gpr;

  /* The va_arg builtin uses a constant distance of 16 *
     UNITS_PER_LONG (r0-r15) to reach the FPRs from the reg_save_area
     pointer.  So even if we are going to save the stack pointer in an
     FPR we need the stack space in order to keep the offsets
     correct.  */
  if (cfun->stdarg && cfun_save_arg_fprs_p)
    {
      cfun_frame_layout.last_save_gpr_slot = STACK_POINTER_REGNUM;

      if (cfun_frame_layout.first_save_gpr_slot == -1)
        cfun_frame_layout.first_save_gpr_slot = STACK_POINTER_REGNUM;
    }

  cfun_frame_layout.frame_size = get_frame_size ();
  if (!TARGET_64BIT && cfun_frame_layout.frame_size > 0x7fff0000)
    fatal_error ("total size of local variables exceeds architecture limit");

  if (!TARGET_PACKED_STACK)
    {
      /* Fixed stack layout.  */
      cfun_frame_layout.backchain_offset = 0;
      cfun_frame_layout.f0_offset = 16 * UNITS_PER_LONG;
      cfun_frame_layout.f4_offset = cfun_frame_layout.f0_offset + 2 * 8;
      cfun_frame_layout.f8_offset = -cfun_frame_layout.high_fprs * 8;
      cfun_frame_layout.gprs_offset = (cfun_frame_layout.first_save_gpr_slot
                                       * UNITS_PER_LONG);
    }
  else if (TARGET_BACKCHAIN)
    {
      /* Kernel stack layout - packed stack, backchain, no float  */
      gcc_assert (TARGET_SOFT_FLOAT);
      cfun_frame_layout.backchain_offset = (STACK_POINTER_OFFSET
                                            - UNITS_PER_LONG);

      /* The distance between the backchain and the return address
         save slot must not change.  So we always need a slot for the
         stack pointer which resides in between.  */
      cfun_frame_layout.last_save_gpr_slot = STACK_POINTER_REGNUM;

      cfun_frame_layout.gprs_offset
        = cfun_frame_layout.backchain_offset - cfun_gprs_save_area_size;

      /* FPRs will not be saved.  Nevertheless pick sane values to
         keep area calculations valid.  */
      cfun_frame_layout.f0_offset =
        cfun_frame_layout.f4_offset =
        cfun_frame_layout.f8_offset = cfun_frame_layout.gprs_offset;
    }
  else
    {
      int num_fprs;

      /* Packed stack layout without backchain.  */

      /* With stdarg FPRs need their dedicated slots.  */
      num_fprs = (TARGET_64BIT && cfun->stdarg ? 2
                  : (cfun_fpr_save_p (FPR4_REGNUM) +
                     cfun_fpr_save_p (FPR6_REGNUM)));
      cfun_frame_layout.f4_offset = STACK_POINTER_OFFSET - 8 * num_fprs;

      num_fprs = (cfun->stdarg ? 2
                  : (cfun_fpr_save_p (FPR0_REGNUM)
                     + cfun_fpr_save_p (FPR2_REGNUM)));
      cfun_frame_layout.f0_offset = cfun_frame_layout.f4_offset - 8 * num_fprs;

      cfun_frame_layout.gprs_offset
        = cfun_frame_layout.f0_offset - cfun_gprs_save_area_size;

      cfun_frame_layout.f8_offset = (cfun_frame_layout.gprs_offset
                                     - cfun_frame_layout.high_fprs * 8);
    }

  if (cfun_save_high_fprs_p)
    cfun_frame_layout.frame_size += cfun_frame_layout.high_fprs * 8;

  if (!crtl->is_leaf)
    cfun_frame_layout.frame_size += crtl->outgoing_args_size;

  /* In the following cases we have to allocate a STACK_POINTER_OFFSET
     sized area at the bottom of the stack.  This is required also for
     leaf functions.  When GCC generates a local stack reference it
     will always add STACK_POINTER_OFFSET to all these references.  */
  if (crtl->is_leaf
      && !TARGET_TPF_PROFILING
      && cfun_frame_layout.frame_size == 0
      && !cfun->calls_alloca)
    return;

  /* Calculate the number of bytes we have used in our own register
     save area.  With the packed stack layout we can re-use the
     remaining bytes for normal stack elements.  */

  if (TARGET_PACKED_STACK)
    lowest_offset = MIN (MIN (cfun_frame_layout.f0_offset,
                              cfun_frame_layout.f4_offset),
                         cfun_frame_layout.gprs_offset);
  else
    lowest_offset = 0;

  if (TARGET_BACKCHAIN)
    lowest_offset = MIN (lowest_offset, cfun_frame_layout.backchain_offset);

  cfun_frame_layout.frame_size += STACK_POINTER_OFFSET - lowest_offset;

  /* If under 31 bit an odd number of gprs has to be saved we have to
     adjust the frame size to sustain 8 byte alignment of stack
     frames.  */
  cfun_frame_layout.frame_size = ((cfun_frame_layout.frame_size +
                                   STACK_BOUNDARY / BITS_PER_UNIT - 1)
                                  & ~(STACK_BOUNDARY / BITS_PER_UNIT - 1));
}

/* Generate frame layout.  Fills in register and frame data for the current
   function in cfun->machine.  This routine can be called multiple times;
   it will re-do the complete frame layout every time.  */

static void
s390_init_frame_layout (void)
{
  HOST_WIDE_INT frame_size;
  int base_used;

  gcc_assert (!reload_completed);

  /* On S/390 machines, we may need to perform branch splitting, which
     will require both base and return address register.  We have no
     choice but to assume we're going to need them until right at the
     end of the machine dependent reorg phase.  */
  if (!TARGET_CPU_ZARCH)
    cfun->machine->split_branches_pending_p = true;

  do
    {
      frame_size = cfun_frame_layout.frame_size;

      /* Try to predict whether we'll need the base register.  */
      base_used = cfun->machine->split_branches_pending_p
                  || crtl->uses_const_pool
                  || (!DISP_IN_RANGE (frame_size)
                      && !CONST_OK_FOR_K (frame_size));

      /* Decide which register to use as literal pool base.  In small
         leaf functions, try to use an unused call-clobbered register
         as base register to avoid save/restore overhead.  */
      if (!base_used)
        cfun->machine->base_reg = NULL_RTX;
      else if (crtl->is_leaf && !df_regs_ever_live_p (5))
        cfun->machine->base_reg = gen_rtx_REG (Pmode, 5);
      else
        cfun->machine->base_reg = gen_rtx_REG (Pmode, BASE_REGNUM);

      s390_register_info ();
      s390_frame_info ();
    }
  while (frame_size != cfun_frame_layout.frame_size);
}

/* Remove the FPR clobbers from a tbegin insn if it can be proven that
   the TX is nonescaping.  A transaction is considered escaping if
   there is at least one path from tbegin returning CC0 to the
   function exit block without an tend.

   The check so far has some limitations:
   - only single tbegin/tend BBs are supported
   - the first cond jump after tbegin must separate the CC0 path from ~CC0
   - when CC is copied to a GPR and the CC0 check is done with the GPR
     this is not supported
*/

static void
s390_optimize_nonescaping_tx (void)
{
  const unsigned int CC0 = 1 << 3;
  basic_block tbegin_bb = NULL;
  basic_block tend_bb = NULL;
  basic_block bb;
  rtx_insn *insn;
  bool result = true;
  int bb_index;
  rtx_insn *tbegin_insn = NULL;

  if (!cfun->machine->tbegin_p)
    return;

  for (bb_index = 0; bb_index < n_basic_blocks_for_fn (cfun); bb_index++)
    {
      bb = BASIC_BLOCK_FOR_FN (cfun, bb_index);

      if (!bb)
        continue;

      FOR_BB_INSNS (bb, insn)
        {
          rtx ite, cc, pat, target;
          unsigned HOST_WIDE_INT mask;

          if (!INSN_P (insn) || INSN_CODE (insn) <= 0)
            continue;

          pat = PATTERN (insn);

          if (GET_CODE (pat) == PARALLEL)
            pat = XVECEXP (pat, 0, 0);

          if (GET_CODE (pat) != SET
              || GET_CODE (SET_SRC (pat)) != UNSPEC_VOLATILE)
            continue;

          if (XINT (SET_SRC (pat), 1) == UNSPECV_TBEGIN)
            {
              rtx_insn *tmp;

              tbegin_insn = insn;

              /* Just return if the tbegin doesn't have clobbers.  */
              if (GET_CODE (PATTERN (insn)) != PARALLEL)
                return;

              if (tbegin_bb != NULL)
                return;

              /* Find the next conditional jump.  */
              for (tmp = NEXT_INSN (insn);
                   tmp != NULL_RTX;
                   tmp = NEXT_INSN (tmp))
                {
                  if (reg_set_p (gen_rtx_REG (CCmode, CC_REGNUM), tmp))
                    return;
                  if (!JUMP_P (tmp))
                    continue;

                  ite = SET_SRC (PATTERN (tmp));
                  if (GET_CODE (ite) != IF_THEN_ELSE)
                    continue;

                  cc = XEXP (XEXP (ite, 0), 0);
                  if (!REG_P (cc) || !CC_REGNO_P (REGNO (cc))
                      || GET_MODE (cc) != CCRAWmode
                      || GET_CODE (XEXP (XEXP (ite, 0), 1)) != CONST_INT)
                    return;

                  if (bb->succs->length () != 2)
                    return;

                  mask = INTVAL (XEXP (XEXP (ite, 0), 1));
                  if (GET_CODE (XEXP (ite, 0)) == NE)
                    mask ^= 0xf;

                  if (mask == CC0)
                    target = XEXP (ite, 1);
                  else if (mask == (CC0 ^ 0xf))
                    target = XEXP (ite, 2);
                  else
                    return;

                  {
                    edge_iterator ei;
                    edge e1, e2;

                    ei = ei_start (bb->succs);
                    e1 = ei_safe_edge (ei);
                    ei_next (&ei);
                    e2 = ei_safe_edge (ei);

                    if (e2->flags & EDGE_FALLTHRU)
                      {
                        e2 = e1;
                        e1 = ei_safe_edge (ei);
                      }

                    if (!(e1->flags & EDGE_FALLTHRU))
                      return;

                    tbegin_bb = (target == pc_rtx) ? e1->dest : e2->dest;
                  }
                  if (tmp == BB_END (bb))
                    break;
                }
            }

          if (XINT (SET_SRC (pat), 1) == UNSPECV_TEND)
            {
              if (tend_bb != NULL)
                return;
              tend_bb = bb;
            }
        }
    }

  /* Either we successfully remove the FPR clobbers here or we are not
     able to do anything for this TX.  Both cases don't qualify for
     another look.  */
  cfun->machine->tbegin_p = false;

  if (tbegin_bb == NULL || tend_bb == NULL)
    return;

  calculate_dominance_info (CDI_POST_DOMINATORS);
  result = dominated_by_p (CDI_POST_DOMINATORS, tbegin_bb, tend_bb);
  free_dominance_info (CDI_POST_DOMINATORS);

  if (!result)
    return;

  PATTERN (tbegin_insn) = gen_rtx_PARALLEL (VOIDmode,
                            gen_rtvec (2,
                                       XVECEXP (PATTERN (tbegin_insn), 0, 0),
                                       XVECEXP (PATTERN (tbegin_insn), 0, 1)));
  INSN_CODE (tbegin_insn) = -1;
  df_insn_rescan (tbegin_insn);

  return;
}

/* Return true if it is legal to put a value with MODE into REGNO.  */

bool
s390_hard_regno_mode_ok (unsigned int regno, machine_mode mode)
{
  switch (REGNO_REG_CLASS (regno))
    {
    case FP_REGS:
      if (REGNO_PAIR_OK (regno, mode))
        {
          if (mode == SImode || mode == DImode)
            return true;

          if (FLOAT_MODE_P (mode) && GET_MODE_CLASS (mode) != MODE_VECTOR_FLOAT)
            return true;
        }
      break;
    case ADDR_REGS:
      if (FRAME_REGNO_P (regno) && mode == Pmode)
        return true;

      /* fallthrough */
    case GENERAL_REGS:
      if (REGNO_PAIR_OK (regno, mode))
        {
          if (TARGET_ZARCH
              || (mode != TFmode && mode != TCmode && mode != TDmode))
            return true;
        }
      break;
    case CC_REGS:
      if (GET_MODE_CLASS (mode) == MODE_CC)
        return true;
      break;
    case ACCESS_REGS:
      if (REGNO_PAIR_OK (regno, mode))
        {
          if (mode == SImode || mode == Pmode)
            return true;
        }
      break;
    default:
      return false;
    }

  return false;
}

/* Return nonzero if register OLD_REG can be renamed to register NEW_REG.  */

bool
s390_hard_regno_rename_ok (unsigned int old_reg, unsigned int new_reg)
{
   /* Once we've decided upon a register to use as base register, it must
      no longer be used for any other purpose.  */
  if (cfun->machine->base_reg)
    if (REGNO (cfun->machine->base_reg) == old_reg
        || REGNO (cfun->machine->base_reg) == new_reg)
      return false;

  /* Prevent regrename from using call-saved regs which haven't
     actually been saved.  This is necessary since regrename assumes
     the backend save/restore decisions are based on
     df_regs_ever_live.  Since we have our own routine we have to tell
     regrename manually about it.  */
  if (GENERAL_REGNO_P (new_reg)
      && !call_really_used_regs[new_reg]
      && cfun_gpr_save_slot (new_reg) == 0)
    return false;

  return true;
}

/* Return nonzero if register REGNO can be used as a scratch register
   in peephole2.  */

static bool
s390_hard_regno_scratch_ok (unsigned int regno)
{
  /* See s390_hard_regno_rename_ok.  */
  if (GENERAL_REGNO_P (regno)
      && !call_really_used_regs[regno]
      && cfun_gpr_save_slot (regno) == 0)
    return false;

  return true;
}

/* Maximum number of registers to represent a value of mode MODE
   in a register of class RCLASS.  */

int
s390_class_max_nregs (enum reg_class rclass, machine_mode mode)
{
  switch (rclass)
    {
    case FP_REGS:
      if (GET_MODE_CLASS (mode) == MODE_COMPLEX_FLOAT)
        return 2 * ((GET_MODE_SIZE (mode) / 2 + 8 - 1) / 8);
      else
        return (GET_MODE_SIZE (mode) + 8 - 1) / 8;
    case ACCESS_REGS:
      return (GET_MODE_SIZE (mode) + 4 - 1) / 4;
    default:
      break;
    }
  return (GET_MODE_SIZE (mode) + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
}

/* Return true if we use LRA instead of reload pass.  */
static bool
s390_lra_p (void)
{
  return s390_lra_flag;
}

/* Return true if register FROM can be eliminated via register TO.  */

static bool
s390_can_eliminate (const int from, const int to)
{
  /* On zSeries machines, we have not marked the base register as fixed.
     Instead, we have an elimination rule BASE_REGNUM -> BASE_REGNUM.
     If a function requires the base register, we say here that this
     elimination cannot be performed.  This will cause reload to free
     up the base register (as if it were fixed).  On the other hand,
     if the current function does *not* require the base register, we
     say here the elimination succeeds, which in turn allows reload
     to allocate the base register for any other purpose.  */
  if (from == BASE_REGNUM && to == BASE_REGNUM)
    {
      if (TARGET_CPU_ZARCH)
        {
          s390_init_frame_layout ();
          return cfun->machine->base_reg == NULL_RTX;
        }

      return false;
    }

  /* Everything else must point into the stack frame.  */
  gcc_assert (to == STACK_POINTER_REGNUM
              || to == HARD_FRAME_POINTER_REGNUM);

  gcc_assert (from == FRAME_POINTER_REGNUM
              || from == ARG_POINTER_REGNUM
              || from == RETURN_ADDRESS_POINTER_REGNUM);

  /* Make sure we actually saved the return address.  */
  if (from == RETURN_ADDRESS_POINTER_REGNUM)
    if (!crtl->calls_eh_return
        && !cfun->stdarg
        && !cfun_frame_layout.save_return_addr_p)
      return false;

  return true;
}

/* Return offset between register FROM and TO initially after prolog.  */

HOST_WIDE_INT
s390_initial_elimination_offset (int from, int to)
{
  HOST_WIDE_INT offset;

  /* ??? Why are we called for non-eliminable pairs?  */
  if (!s390_can_eliminate (from, to))
    return 0;

  switch (from)
    {
    case FRAME_POINTER_REGNUM:
      offset = (get_frame_size()
                + STACK_POINTER_OFFSET
                + crtl->outgoing_args_size);
      break;

    case ARG_POINTER_REGNUM:
      s390_init_frame_layout ();
      offset = cfun_frame_layout.frame_size + STACK_POINTER_OFFSET;
      break;

    case RETURN_ADDRESS_POINTER_REGNUM:
      s390_init_frame_layout ();

      if (cfun_frame_layout.first_save_gpr_slot == -1)
        {
          /* If it turns out that for stdarg nothing went into the reg
             save area we also do not need the return address
             pointer.  */
          if (cfun->stdarg && !cfun_save_arg_fprs_p)
            return 0;

          gcc_unreachable ();
        }

      /* In order to make the following work it is not necessary for
         r14 to have a save slot.  It is sufficient if one other GPR
         got one.  Since the GPRs are always stored without gaps we
         are able to calculate where the r14 save slot would
         reside.  */
      offset = (cfun_frame_layout.frame_size + cfun_frame_layout.gprs_offset +
                (RETURN_REGNUM - cfun_frame_layout.first_save_gpr_slot) *
                UNITS_PER_LONG);
      break;

    case BASE_REGNUM:
      offset = 0;
      break;

    default:
      gcc_unreachable ();
    }

  return offset;
}

/* Emit insn to save fpr REGNUM at offset OFFSET relative
   to register BASE.  Return generated insn.  */

static rtx
save_fpr (rtx base, int offset, int regnum)
{
  rtx addr;
  addr = gen_rtx_MEM (DFmode, plus_constant (Pmode, base, offset));

  if (regnum >= 16 && regnum <= (16 + FP_ARG_NUM_REG))
    set_mem_alias_set (addr, get_varargs_alias_set ());
  else
    set_mem_alias_set (addr, get_frame_alias_set ());

  return emit_move_insn (addr, gen_rtx_REG (DFmode, regnum));
}

/* Emit insn to restore fpr REGNUM from offset OFFSET relative
   to register BASE.  Return generated insn.  */

static rtx
restore_fpr (rtx base, int offset, int regnum)
{
  rtx addr;
  addr = gen_rtx_MEM (DFmode, plus_constant (Pmode, base, offset));
  set_mem_alias_set (addr, get_frame_alias_set ());

  return emit_move_insn (gen_rtx_REG (DFmode, regnum), addr);
}

/* Return true if REGNO is a global register, but not one
   of the special ones that need to be saved/restored in anyway.  */

static inline bool
global_not_special_regno_p (int regno)
{
  return (global_regs[regno]
          /* These registers are special and need to be
             restored in any case.  */
          && !(regno == STACK_POINTER_REGNUM
               || regno == RETURN_REGNUM
               || regno == BASE_REGNUM
               || (flag_pic && regno == (int)PIC_OFFSET_TABLE_REGNUM)));
}

/* Generate insn to save registers FIRST to LAST into
   the register save area located at offset OFFSET
   relative to register BASE.  */

static rtx
save_gprs (rtx base, int offset, int first, int last)
{
  rtx addr, insn, note;
  int i;

  addr = plus_constant (Pmode, base, offset);
  addr = gen_rtx_MEM (Pmode, addr);

  set_mem_alias_set (addr, get_frame_alias_set ());

  /* Special-case single register.  */
  if (first == last)
    {
      if (TARGET_64BIT)
        insn = gen_movdi (addr, gen_rtx_REG (Pmode, first));
      else
        insn = gen_movsi (addr, gen_rtx_REG (Pmode, first));

      if (!global_not_special_regno_p (first))
        RTX_FRAME_RELATED_P (insn) = 1;
      return insn;
    }


  insn = gen_store_multiple (addr,
                             gen_rtx_REG (Pmode, first),
                             GEN_INT (last - first + 1));

  if (first <= 6 && cfun->stdarg)
    for (i = 0; i < XVECLEN (PATTERN (insn), 0); i++)
      {
        rtx mem = XEXP (XVECEXP (PATTERN (insn), 0, i), 0);

        if (first + i <= 6)
          set_mem_alias_set (mem, get_varargs_alias_set ());
      }

  /* We need to set the FRAME_RELATED flag on all SETs
     inside the store-multiple pattern.

     However, we must not emit DWARF records for registers 2..5
     if they are stored for use by variable arguments ...

     ??? Unfortunately, it is not enough to simply not the
     FRAME_RELATED flags for those SETs, because the first SET
     of the PARALLEL is always treated as if it had the flag
     set, even if it does not.  Therefore we emit a new pattern
     without those registers as REG_FRAME_RELATED_EXPR note.  */

  if (first >= 6 && !global_not_special_regno_p (first))
    {
      rtx pat = PATTERN (insn);

      for (i = 0; i < XVECLEN (pat, 0); i++)
        if (GET_CODE (XVECEXP (pat, 0, i)) == SET
            && !global_not_special_regno_p (REGNO (SET_SRC (XVECEXP (pat,
                                                                     0, i)))))
          RTX_FRAME_RELATED_P (XVECEXP (pat, 0, i)) = 1;

      RTX_FRAME_RELATED_P (insn) = 1;
    }
  else if (last >= 6)
    {
      int start;

      for (start = first >= 6 ? first : 6; start <= last; start++)
        if (!global_not_special_regno_p (start))
          break;

      if (start > last)
        return insn;

      addr = plus_constant (Pmode, base,
                            offset + (start - first) * UNITS_PER_LONG);

      if (start == last)
        {
          if (TARGET_64BIT)
            note = gen_movdi (gen_rtx_MEM (Pmode, addr),
                              gen_rtx_REG (Pmode, start));
          else
            note = gen_movsi (gen_rtx_MEM (Pmode, addr),
                              gen_rtx_REG (Pmode, start));
          note = PATTERN (note);

          add_reg_note (insn, REG_FRAME_RELATED_EXPR, note);
          RTX_FRAME_RELATED_P (insn) = 1;

          return insn;
        }

      note = gen_store_multiple (gen_rtx_MEM (Pmode, addr),
                                 gen_rtx_REG (Pmode, start),
                                 GEN_INT (last - start + 1));
      note = PATTERN (note);

      add_reg_note (insn, REG_FRAME_RELATED_EXPR, note);

      for (i = 0; i < XVECLEN (note, 0); i++)
        if (GET_CODE (XVECEXP (note, 0, i)) == SET
            && !global_not_special_regno_p (REGNO (SET_SRC (XVECEXP (note,
                                                                     0, i)))))
          RTX_FRAME_RELATED_P (XVECEXP (note, 0, i)) = 1;

      RTX_FRAME_RELATED_P (insn) = 1;
    }

  return insn;
}

/* Generate insn to restore registers FIRST to LAST from
   the register save area located at offset OFFSET
   relative to register BASE.  */

static rtx
restore_gprs (rtx base, int offset, int first, int last)
{
  rtx addr, insn;

  addr = plus_constant (Pmode, base, offset);
  addr = gen_rtx_MEM (Pmode, addr);
  set_mem_alias_set (addr, get_frame_alias_set ());

  /* Special-case single register.  */
  if (first == last)
    {
      if (TARGET_64BIT)
        insn = gen_movdi (gen_rtx_REG (Pmode, first), addr);
      else
        insn = gen_movsi (gen_rtx_REG (Pmode, first), addr);

      RTX_FRAME_RELATED_P (insn) = 1;
      return insn;
    }

  insn = gen_load_multiple (gen_rtx_REG (Pmode, first),
                            addr,
                            GEN_INT (last - first + 1));
  RTX_FRAME_RELATED_P (insn) = 1;
  return insn;
}

/* Return insn sequence to load the GOT register.  */

static GTY(()) rtx got_symbol;
rtx_insn *
s390_load_got (void)
{
  rtx_insn *insns;

  /* We cannot use pic_offset_table_rtx here since we use this
     function also for non-pic if __tls_get_offset is called and in
     that case PIC_OFFSET_TABLE_REGNUM as well as pic_offset_table_rtx
     aren't usable.  */
  rtx got_rtx = gen_rtx_REG (Pmode, 12);

  if (!got_symbol)
    {
      got_symbol = gen_rtx_SYMBOL_REF (Pmode, "_GLOBAL_OFFSET_TABLE_");
      SYMBOL_REF_FLAGS (got_symbol) = SYMBOL_FLAG_LOCAL;
    }

  start_sequence ();

  if (TARGET_CPU_ZARCH)
    {
      emit_move_insn (got_rtx, got_symbol);
    }
  else
    {
      rtx offset;

      offset = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, got_symbol),
                               UNSPEC_LTREL_OFFSET);
      offset = gen_rtx_CONST (Pmode, offset);
      offset = force_const_mem (Pmode, offset);

      emit_move_insn (got_rtx, offset);

      offset = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, XEXP (offset, 0)),
                               UNSPEC_LTREL_BASE);
      offset = gen_rtx_PLUS (Pmode, got_rtx, offset);

      emit_move_insn (got_rtx, offset);
    }

  insns = get_insns ();
  end_sequence ();
  return insns;
}

/* This ties together stack memory (MEM with an alias set of frame_alias_set)
   and the change to the stack pointer.  */

static void
s390_emit_stack_tie (void)
{
  rtx mem = gen_frame_mem (BLKmode,
                           gen_rtx_REG (Pmode, STACK_POINTER_REGNUM));

  emit_insn (gen_stack_tie (mem));
}

/* Copy GPRS into FPR save slots.  */

static void
s390_save_gprs_to_fprs (void)
{
  int i;

  if (!TARGET_Z10 || !TARGET_HARD_FLOAT || !crtl->is_leaf)
    return;

  for (i = 6; i < 16; i++)
    {
      if (FP_REGNO_P (cfun_gpr_save_slot (i)))
        {
          rtx_insn *insn =
            emit_move_insn (gen_rtx_REG (DImode, cfun_gpr_save_slot (i)),
                            gen_rtx_REG (DImode, i));
          RTX_FRAME_RELATED_P (insn) = 1;
        }
    }
}

/* Restore GPRs from FPR save slots.  */

static void
s390_restore_gprs_from_fprs (void)
{
  int i;

  if (!TARGET_Z10 || !TARGET_HARD_FLOAT || !crtl->is_leaf)
    return;

  for (i = 6; i < 16; i++)
    {
      if (FP_REGNO_P (cfun_gpr_save_slot (i)))
        {
          rtx_insn *insn =
            emit_move_insn (gen_rtx_REG (DImode, i),
                            gen_rtx_REG (DImode, cfun_gpr_save_slot (i)));
          df_set_regs_ever_live (i, true);
          add_reg_note (insn, REG_CFA_RESTORE, gen_rtx_REG (DImode, i));
          if (i == STACK_POINTER_REGNUM)
            add_reg_note (insn, REG_CFA_DEF_CFA,
                          plus_constant (Pmode, stack_pointer_rtx,
                                         STACK_POINTER_OFFSET));
          RTX_FRAME_RELATED_P (insn) = 1;
        }
    }
}


/* A pass run immediately before shrink-wrapping and prologue and epilogue
   generation.  */

namespace {

const pass_data pass_data_s390_early_mach =
{
  RTL_PASS, /* type */
  "early_mach", /* name */
  OPTGROUP_NONE, /* optinfo_flags */
  TV_MACH_DEP, /* tv_id */
  0, /* properties_required */
  0, /* properties_provided */
  0, /* properties_destroyed */
  0, /* todo_flags_start */
  ( TODO_df_verify | TODO_df_finish ), /* todo_flags_finish */
};

class pass_s390_early_mach : public rtl_opt_pass
{
public:
  pass_s390_early_mach (gcc::context *ctxt)
    : rtl_opt_pass (pass_data_s390_early_mach, ctxt)
  {}

  /* opt_pass methods: */
  virtual unsigned int execute (function *);

}; // class pass_s390_early_mach

unsigned int
pass_s390_early_mach::execute (function *fun)
{
  rtx_insn *insn;

  /* Try to get rid of the FPR clobbers.  */
  s390_optimize_nonescaping_tx ();

  /* Re-compute register info.  */
  s390_register_info ();

  /* If we're using a base register, ensure that it is always valid for
     the first non-prologue instruction.  */
  if (fun->machine->base_reg)
    emit_insn_at_entry (gen_main_pool (fun->machine->base_reg));

  /* Annotate all constant pool references to let the scheduler know
     they implicitly use the base register.  */
  for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
    if (INSN_P (insn))
      {
        annotate_constant_pool_refs (&PATTERN (insn));
        df_insn_rescan (insn);
      }
  return 0;
}

} // anon namespace

/* Expand the prologue into a bunch of separate insns.  */

void
s390_emit_prologue (void)
{
  rtx insn, addr;
  rtx temp_reg;
  int i;
  int offset;
  int next_fpr = 0;

  /* Choose best register to use for temp use within prologue.
     See below for why TPF must use the register 1.  */

  if (!has_hard_reg_initial_val (Pmode, RETURN_REGNUM)
      && !crtl->is_leaf
      && !TARGET_TPF_PROFILING)
    temp_reg = gen_rtx_REG (Pmode, RETURN_REGNUM);
  else
    temp_reg = gen_rtx_REG (Pmode, 1);

  s390_save_gprs_to_fprs ();

  /* Save call saved gprs.  */
  if (cfun_frame_layout.first_save_gpr != -1)
    {
      insn = save_gprs (stack_pointer_rtx,
                        cfun_frame_layout.gprs_offset +
                        UNITS_PER_LONG * (cfun_frame_layout.first_save_gpr
                                          - cfun_frame_layout.first_save_gpr_slot),
                        cfun_frame_layout.first_save_gpr,
                        cfun_frame_layout.last_save_gpr);
      emit_insn (insn);
    }

  /* Dummy insn to mark literal pool slot.  */

  if (cfun->machine->base_reg)
    emit_insn (gen_main_pool (cfun->machine->base_reg));

  offset = cfun_frame_layout.f0_offset;

  /* Save f0 and f2.  */
  for (i = FPR0_REGNUM; i <= FPR0_REGNUM + 1; i++)
    {
      if (cfun_fpr_save_p (i))
        {
          save_fpr (stack_pointer_rtx, offset, i);
          offset += 8;
        }
      else if (!TARGET_PACKED_STACK || cfun->stdarg)
        offset += 8;
    }

  /* Save f4 and f6.  */
  offset = cfun_frame_layout.f4_offset;
  for (i = FPR4_REGNUM; i <= FPR4_REGNUM + 1; i++)
    {
      if (cfun_fpr_save_p (i))
        {
          insn = save_fpr (stack_pointer_rtx, offset, i);
          offset += 8;

          /* If f4 and f6 are call clobbered they are saved due to
             stdargs and therefore are not frame related.  */
          if (!call_really_used_regs[i])
            RTX_FRAME_RELATED_P (insn) = 1;
        }
      else if (!TARGET_PACKED_STACK || call_really_used_regs[i])
        offset += 8;
    }

  if (TARGET_PACKED_STACK
      && cfun_save_high_fprs_p
      && cfun_frame_layout.f8_offset + cfun_frame_layout.high_fprs * 8 > 0)
    {
      offset = (cfun_frame_layout.f8_offset
                + (cfun_frame_layout.high_fprs - 1) * 8);

      for (i = FPR15_REGNUM; i >= FPR8_REGNUM && offset >= 0; i--)
        if (cfun_fpr_save_p (i))
          {
            insn = save_fpr (stack_pointer_rtx, offset, i);

            RTX_FRAME_RELATED_P (insn) = 1;
            offset -= 8;
          }
      if (offset >= cfun_frame_layout.f8_offset)
        next_fpr = i;
    }

  if (!TARGET_PACKED_STACK)
    next_fpr = cfun_save_high_fprs_p ? FPR15_REGNUM : 0;

  if (flag_stack_usage_info)
    current_function_static_stack_size = cfun_frame_layout.frame_size;

  /* Decrement stack pointer.  */

  if (cfun_frame_layout.frame_size > 0)
    {
      rtx frame_off = GEN_INT (-cfun_frame_layout.frame_size);
      rtx real_frame_off;

      if (s390_stack_size)
        {
          HOST_WIDE_INT stack_guard;

          if (s390_stack_guard)
            stack_guard = s390_stack_guard;
          else
            {
              /* If no value for stack guard is provided the smallest power of 2
                 larger than the current frame size is chosen.  */
              stack_guard = 1;
              while (stack_guard < cfun_frame_layout.frame_size)
                stack_guard <<= 1;
            }

          if (cfun_frame_layout.frame_size >= s390_stack_size)
            {
              warning (0, "frame size of function %qs is %wd"
                       " bytes exceeding user provided stack limit of "
                       "%d bytes.  "
                       "An unconditional trap is added.",
                       current_function_name(), cfun_frame_layout.frame_size,
                       s390_stack_size);
              emit_insn (gen_trap ());
            }
          else
            {
              /* stack_guard has to be smaller than s390_stack_size.
                 Otherwise we would emit an AND with zero which would
                 not match the test under mask pattern.  */
              if (stack_guard >= s390_stack_size)
                {
                  warning (0, "frame size of function %qs is %wd"
                           " bytes which is more than half the stack size. "
                           "The dynamic check would not be reliable. "
                           "No check emitted for this function.",
                           current_function_name(),
                           cfun_frame_layout.frame_size);
                }
              else
                {
                  HOST_WIDE_INT stack_check_mask = ((s390_stack_size - 1)
                                                    & ~(stack_guard - 1));

                  rtx t = gen_rtx_AND (Pmode, stack_pointer_rtx,
                                       GEN_INT (stack_check_mask));
                  if (TARGET_64BIT)
                    emit_insn (gen_ctrapdi4 (gen_rtx_EQ (VOIDmode,
                                                         t, const0_rtx),
                                             t, const0_rtx, const0_rtx));
                  else
                    emit_insn (gen_ctrapsi4 (gen_rtx_EQ (VOIDmode,
                                                         t, const0_rtx),
                                             t, const0_rtx, const0_rtx));
                }
            }
        }

      if (s390_warn_framesize > 0
          && cfun_frame_layout.frame_size >= s390_warn_framesize)
        warning (0, "frame size of %qs is %wd bytes",
                 current_function_name (), cfun_frame_layout.frame_size);

      if (s390_warn_dynamicstack_p && cfun->calls_alloca)
        warning (0, "%qs uses dynamic stack allocation", current_function_name ());

      /* Save incoming stack pointer into temp reg.  */
      if (TARGET_BACKCHAIN || next_fpr)
        insn = emit_insn (gen_move_insn (temp_reg, stack_pointer_rtx));

      /* Subtract frame size from stack pointer.  */

      if (DISP_IN_RANGE (INTVAL (frame_off)))
        {
          insn = gen_rtx_SET (VOIDmode, stack_pointer_rtx,
                              gen_rtx_PLUS (Pmode, stack_pointer_rtx,
                                            frame_off));
          insn = emit_insn (insn);
        }
      else
        {
          if (!CONST_OK_FOR_K (INTVAL (frame_off)))
            frame_off = force_const_mem (Pmode, frame_off);

          insn = emit_insn (gen_add2_insn (stack_pointer_rtx, frame_off));
          annotate_constant_pool_refs (&PATTERN (insn));
        }

      RTX_FRAME_RELATED_P (insn) = 1;
      real_frame_off = GEN_INT (-cfun_frame_layout.frame_size);
      add_reg_note (insn, REG_FRAME_RELATED_EXPR,
                    gen_rtx_SET (VOIDmode, stack_pointer_rtx,
                                 gen_rtx_PLUS (Pmode, stack_pointer_rtx,
                                               real_frame_off)));

      /* Set backchain.  */

      if (TARGET_BACKCHAIN)
        {
          if (cfun_frame_layout.backchain_offset)
            addr = gen_rtx_MEM (Pmode,
                                plus_constant (Pmode, stack_pointer_rtx,
                                  cfun_frame_layout.backchain_offset));
          else
            addr = gen_rtx_MEM (Pmode, stack_pointer_rtx);
          set_mem_alias_set (addr, get_frame_alias_set ());
          insn = emit_insn (gen_move_insn (addr, temp_reg));
        }

      /* If we support non-call exceptions (e.g. for Java),
         we need to make sure the backchain pointer is set up
         before any possibly trapping memory access.  */
      if (TARGET_BACKCHAIN && cfun->can_throw_non_call_exceptions)
        {
          addr = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode));
          emit_clobber (addr);
        }
    }

  /* Save fprs 8 - 15 (64 bit ABI).  */

  if (cfun_save_high_fprs_p && next_fpr)
    {
      /* If the stack might be accessed through a different register
         we have to make sure that the stack pointer decrement is not
         moved below the use of the stack slots.  */
      s390_emit_stack_tie ();

      insn = emit_insn (gen_add2_insn (temp_reg,
                                       GEN_INT (cfun_frame_layout.f8_offset)));

      offset = 0;

      for (i = FPR8_REGNUM; i <= next_fpr; i++)
        if (cfun_fpr_save_p (i))
          {
            rtx addr = plus_constant (Pmode, stack_pointer_rtx,
                                      cfun_frame_layout.frame_size
                                      + cfun_frame_layout.f8_offset
                                      + offset);

            insn = save_fpr (temp_reg, offset, i);
            offset += 8;
            RTX_FRAME_RELATED_P (insn) = 1;
            add_reg_note (insn, REG_FRAME_RELATED_EXPR,
                          gen_rtx_SET (VOIDmode,
                                       gen_rtx_MEM (DFmode, addr),
                                       gen_rtx_REG (DFmode, i)));
          }
    }

  /* Set frame pointer, if needed.  */

  if (frame_pointer_needed)
    {
      insn = emit_move_insn (hard_frame_pointer_rtx, stack_pointer_rtx);
      RTX_FRAME_RELATED_P (insn) = 1;
    }

  /* Set up got pointer, if needed.  */

  if (flag_pic && df_regs_ever_live_p (PIC_OFFSET_TABLE_REGNUM))
    {
      rtx_insn *insns = s390_load_got ();

      for (rtx_insn *insn = insns; insn; insn = NEXT_INSN (insn))
        annotate_constant_pool_refs (&PATTERN (insn));

      emit_insn (insns);
    }

  if (TARGET_TPF_PROFILING)
    {
      /* Generate a BAS instruction to serve as a function
         entry intercept to facilitate the use of tracing
         algorithms located at the branch target.  */
      emit_insn (gen_prologue_tpf ());

      /* Emit a blockage here so that all code
         lies between the profiling mechanisms.  */
      emit_insn (gen_blockage ());
    }
}

/* Expand the epilogue into a bunch of separate insns.  */

void
s390_emit_epilogue (bool sibcall)
{
  rtx frame_pointer, return_reg, cfa_restores = NULL_RTX;
  int area_bottom, area_top, offset = 0;
  int next_offset;
  rtvec p;
  int i;

  if (TARGET_TPF_PROFILING)
    {

      /* Generate a BAS instruction to serve as a function
         entry intercept to facilitate the use of tracing
         algorithms located at the branch target.  */

      /* Emit a blockage here so that all code
         lies between the profiling mechanisms.  */
      emit_insn (gen_blockage ());

      emit_insn (gen_epilogue_tpf ());
    }

  /* Check whether to use frame or stack pointer for restore.  */

  frame_pointer = (frame_pointer_needed
                   ? hard_frame_pointer_rtx : stack_pointer_rtx);

  s390_frame_area (&area_bottom, &area_top);

  /* Check whether we can access the register save area.
     If not, increment the frame pointer as required.  */

  if (area_top <= area_bottom)
    {
      /* Nothing to restore.  */
    }
  else if (DISP_IN_RANGE (cfun_frame_layout.frame_size + area_bottom)
           && DISP_IN_RANGE (cfun_frame_layout.frame_size + area_top - 1))
    {
      /* Area is in range.  */
      offset = cfun_frame_layout.frame_size;
    }
  else
    {
      rtx insn, frame_off, cfa;

      offset = area_bottom < 0 ? -area_bottom : 0;
      frame_off = GEN_INT (cfun_frame_layout.frame_size - offset);

      cfa = gen_rtx_SET (VOIDmode, frame_pointer,
                         gen_rtx_PLUS (Pmode, frame_pointer, frame_off));
      if (DISP_IN_RANGE (INTVAL (frame_off)))
        {
          insn = gen_rtx_SET (VOIDmode, frame_pointer,
                              gen_rtx_PLUS (Pmode, frame_pointer, frame_off));
          insn = emit_insn (insn);
        }
      else
        {
          if (!CONST_OK_FOR_K (INTVAL (frame_off)))
            frame_off = force_const_mem (Pmode, frame_off);

          insn = emit_insn (gen_add2_insn (frame_pointer, frame_off));
          annotate_constant_pool_refs (&PATTERN (insn));
        }
      add_reg_note (insn, REG_CFA_ADJUST_CFA, cfa);
      RTX_FRAME_RELATED_P (insn) = 1;
    }

  /* Restore call saved fprs.  */

  if (TARGET_64BIT)
    {
      if (cfun_save_high_fprs_p)
        {
          next_offset = cfun_frame_layout.f8_offset;
          for (i = FPR8_REGNUM; i <= FPR15_REGNUM; i++)
            {
              if (cfun_fpr_save_p (i))
                {
                  restore_fpr (frame_pointer,
                               offset + next_offset, i);
                  cfa_restores
                    = alloc_reg_note (REG_CFA_RESTORE,
                                      gen_rtx_REG (DFmode, i), cfa_restores);
                  next_offset += 8;
                }
            }
        }

    }
  else
    {
      next_offset = cfun_frame_layout.f4_offset;
      /* f4, f6 */
      for (i = FPR4_REGNUM; i <= FPR4_REGNUM + 1; i++)
        {
          if (cfun_fpr_save_p (i))
            {
              restore_fpr (frame_pointer,
                           offset + next_offset, i);
              cfa_restores
                = alloc_reg_note (REG_CFA_RESTORE,
                                  gen_rtx_REG (DFmode, i), cfa_restores);
              next_offset += 8;
            }
          else if (!TARGET_PACKED_STACK)
            next_offset += 8;
        }

    }

  /* Return register.  */

  return_reg = gen_rtx_REG (Pmode, RETURN_REGNUM);

  /* Restore call saved gprs.  */

  if (cfun_frame_layout.first_restore_gpr != -1)
    {
      rtx insn, addr;
      int i;

      /* Check for global register and save them
         to stack location from where they get restored.  */

      for (i = cfun_frame_layout.first_restore_gpr;
           i <= cfun_frame_layout.last_restore_gpr;
           i++)
        {
          if (global_not_special_regno_p (i))
            {
              addr = plus_constant (Pmode, frame_pointer,
                                    offset + cfun_frame_layout.gprs_offset
                                    + (i - cfun_frame_layout.first_save_gpr_slot)
                                    * UNITS_PER_LONG);
              addr = gen_rtx_MEM (Pmode, addr);
              set_mem_alias_set (addr, get_frame_alias_set ());
              emit_move_insn (addr, gen_rtx_REG (Pmode, i));
            }
          else
            cfa_restores
              = alloc_reg_note (REG_CFA_RESTORE,
                                gen_rtx_REG (Pmode, i), cfa_restores);
        }

      if (! sibcall)
        {
          /* Fetch return address from stack before load multiple,
             this will do good for scheduling.

             Only do this if we already decided that r14 needs to be
             saved to a stack slot. (And not just because r14 happens to
             be in between two GPRs which need saving.)  Otherwise it
             would be difficult to take that decision back in
             s390_optimize_prologue.  */
          if (cfun_gpr_save_slot (RETURN_REGNUM) == -1)
            {
              int return_regnum = find_unused_clobbered_reg();
              if (!return_regnum)
                return_regnum = 4;
              return_reg = gen_rtx_REG (Pmode, return_regnum);

              addr = plus_constant (Pmode, frame_pointer,
                                    offset + cfun_frame_layout.gprs_offset
                                    + (RETURN_REGNUM
                                       - cfun_frame_layout.first_save_gpr_slot)
                                    * UNITS_PER_LONG);
              addr = gen_rtx_MEM (Pmode, addr);
              set_mem_alias_set (addr, get_frame_alias_set ());
              emit_move_insn (return_reg, addr);

              /* Once we did that optimization we have to make sure
                 s390_optimize_prologue does not try to remove the
                 store of r14 since we will not be able to find the
                 load issued here.  */
              cfun_frame_layout.save_return_addr_p = true;
            }
        }

      insn = restore_gprs (frame_pointer,
                           offset + cfun_frame_layout.gprs_offset
                           + (cfun_frame_layout.first_restore_gpr
                              - cfun_frame_layout.first_save_gpr_slot)
                           * UNITS_PER_LONG,
                           cfun_frame_layout.first_restore_gpr,
                           cfun_frame_layout.last_restore_gpr);
      insn = emit_insn (insn);
      REG_NOTES (insn) = cfa_restores;
      add_reg_note (insn, REG_CFA_DEF_CFA,
                    plus_constant (Pmode, stack_pointer_rtx,
                                   STACK_POINTER_OFFSET));
      RTX_FRAME_RELATED_P (insn) = 1;
    }

  s390_restore_gprs_from_fprs ();

  if (! sibcall)
    {

      /* Return to caller.  */

      p = rtvec_alloc (2);

      RTVEC_ELT (p, 0) = ret_rtx;
      RTVEC_ELT (p, 1) = gen_rtx_USE (VOIDmode, return_reg);
      emit_jump_insn (gen_rtx_PARALLEL (VOIDmode, p));
    }
}

/* Implement TARGET_SET_UP_BY_PROLOGUE.  */

static void
s300_set_up_by_prologue (hard_reg_set_container *regs)
{
  if (cfun->machine->base_reg
      && !call_really_used_regs[REGNO (cfun->machine->base_reg)])
    SET_HARD_REG_BIT (regs->set, REGNO (cfun->machine->base_reg));
}

/* Return true if the function can use simple_return to return outside
   of a shrink-wrapped region.  At present shrink-wrapping is supported
   in all cases.  */

bool
s390_can_use_simple_return_insn (void)
{
  return true;
}

/* Return true if the epilogue is guaranteed to contain only a return
   instruction and if a direct return can therefore be used instead.
   One of the main advantages of using direct return instructions
   is that we can then use conditional returns.  */

bool
s390_can_use_return_insn (void)
{
  int i;

  if (!reload_completed)
    return false;

  if (crtl->profile)
    return false;

  if (TARGET_TPF_PROFILING)
    return false;

  for (i = 0; i < 16; i++)
    if (cfun_gpr_save_slot (i))
      return false;

  /* For 31 bit this is not covered by the frame_size check below
     since f4, f6 are saved in the register save area without needing
     additional stack space.  */
  if (!TARGET_64BIT
      && (cfun_fpr_save_p (FPR4_REGNUM) || cfun_fpr_save_p (FPR6_REGNUM)))
    return false;

  if (cfun->machine->base_reg
      && !call_really_used_regs[REGNO (cfun->machine->base_reg)])
    return false;

  return cfun_frame_layout.frame_size == 0;
}

/* Return the size in bytes of a function argument of
   type TYPE and/or mode MODE.  At least one of TYPE or
   MODE must be specified.  */

static int
s390_function_arg_size (machine_mode mode, const_tree type)
{
  if (type)
    return int_size_in_bytes (type);

  /* No type info available for some library calls ...  */
  if (mode != BLKmode)
    return GET_MODE_SIZE (mode);

  /* If we have neither type nor mode, abort */
  gcc_unreachable ();
}

/* Return true if a function argument of type TYPE and mode MODE
   is to be passed in a floating-point register, if available.  */

static bool
s390_function_arg_float (machine_mode mode, const_tree type)
{
  int size = s390_function_arg_size (mode, type);
  if (size > 8)
    return false;

  /* Soft-float changes the ABI: no floating-point registers are used.  */
  if (TARGET_SOFT_FLOAT)
    return false;

  /* No type info available for some library calls ...  */
  if (!type)
    return mode == SFmode || mode == DFmode || mode == SDmode || mode == DDmode;

  /* The ABI says that record types with a single member are treated
     just like that member would be.  */
  while (TREE_CODE (type) == RECORD_TYPE)
    {
      tree field, single = NULL_TREE;

      for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
        {
          if (TREE_CODE (field) != FIELD_DECL)
            continue;

          if (single == NULL_TREE)
            single = TREE_TYPE (field);
          else
            return false;
        }

      if (single == NULL_TREE)
        return false;
      else
        type = single;
    }

  return TREE_CODE (type) == REAL_TYPE;
}

/* Return true if a function argument of type TYPE and mode MODE
   is to be passed in an integer register, or a pair of integer
   registers, if available.  */

static bool
s390_function_arg_integer (machine_mode mode, const_tree type)
{
  int size = s390_function_arg_size (mode, type);
  if (size > 8)
    return false;

  /* No type info available for some library calls ...  */
  if (!type)
    return GET_MODE_CLASS (mode) == MODE_INT
           || (TARGET_SOFT_FLOAT &&  SCALAR_FLOAT_MODE_P (mode));

  /* We accept small integral (and similar) types.  */
  if (INTEGRAL_TYPE_P (type)
      || POINTER_TYPE_P (type)
      || TREE_CODE (type) == NULLPTR_TYPE
      || TREE_CODE (type) == OFFSET_TYPE
      || (TARGET_SOFT_FLOAT && TREE_CODE (type) == REAL_TYPE))
    return true;

  /* We also accept structs of size 1, 2, 4, 8 that are not
     passed in floating-point registers.  */
  if (AGGREGATE_TYPE_P (type)
      && exact_log2 (size) >= 0
      && !s390_function_arg_float (mode, type))
    return true;

  return false;
}

/* Return 1 if a function argument of type TYPE and mode MODE
   is to be passed by reference.  The ABI specifies that only
   structures of size 1, 2, 4, or 8 bytes are passed by value,
   all other structures (and complex numbers) are passed by
   reference.  */

static bool
s390_pass_by_reference (cumulative_args_t ca ATTRIBUTE_UNUSED,
                        machine_mode mode, const_tree type,
                        bool named ATTRIBUTE_UNUSED)
{
  int size = s390_function_arg_size (mode, type);
  if (size > 8)
    return true;

  if (type)
    {
      if (AGGREGATE_TYPE_P (type) && exact_log2 (size) < 0)
        return 1;

      if (TREE_CODE (type) == COMPLEX_TYPE
          || TREE_CODE (type) == VECTOR_TYPE)
        return 1;
    }

  return 0;
}

/* Update the data in CUM to advance over an argument of mode MODE and
   data type TYPE.  (TYPE is null for libcalls where that information
   may not be available.).  The boolean NAMED specifies whether the
   argument is a named argument (as opposed to an unnamed argument
   matching an ellipsis).  */

static void
s390_function_arg_advance (cumulative_args_t cum_v, machine_mode mode,
                           const_tree type, bool named ATTRIBUTE_UNUSED)
{
  CUMULATIVE_ARGS *cum = get_cumulative_args (cum_v);

  if (s390_function_arg_float (mode, type))
    {
      cum->fprs += 1;
    }
  else if (s390_function_arg_integer (mode, type))
    {
      int size = s390_function_arg_size (mode, type);
      cum->gprs += ((size + UNITS_PER_LONG - 1) / UNITS_PER_LONG);
    }
  else
    gcc_unreachable ();
}

/* Define where to put the arguments to a function.
   Value is zero to push the argument on the stack,
   or a hard register in which to store the argument.

   MODE is the argument's machine mode.
   TYPE is the data type of the argument (as a tree).
    This is null for libcalls where that information may
    not be available.
   CUM is a variable of type CUMULATIVE_ARGS which gives info about
    the preceding args and about the function being called.
   NAMED is nonzero if this argument is a named parameter
    (otherwise it is an extra parameter matching an ellipsis).

   On S/390, we use general purpose registers 2 through 6 to
   pass integer, pointer, and certain structure arguments, and
   floating point registers 0 and 2 (0, 2, 4, and 6 on 64-bit)
   to pass floating point arguments.  All remaining arguments
   are pushed to the stack.  */

static rtx
s390_function_arg (cumulative_args_t cum_v, machine_mode mode,
                   const_tree type, bool named ATTRIBUTE_UNUSED)
{
  CUMULATIVE_ARGS *cum = get_cumulative_args (cum_v);

  if (s390_function_arg_float (mode, type))
    {
      if (cum->fprs + 1 > FP_ARG_NUM_REG)
        return 0;
      else
        return gen_rtx_REG (mode, cum->fprs + 16);
    }
  else if (s390_function_arg_integer (mode, type))
    {
      int size = s390_function_arg_size (mode, type);
      int n_gprs = (size + UNITS_PER_LONG - 1) / UNITS_PER_LONG;

      if (cum->gprs + n_gprs > GP_ARG_NUM_REG)
        return 0;
      else if (n_gprs == 1 || UNITS_PER_WORD == UNITS_PER_LONG)
        return gen_rtx_REG (mode, cum->gprs + 2);
      else if (n_gprs == 2)
        {
          rtvec p = rtvec_alloc (2);

          RTVEC_ELT (p, 0)
            = gen_rtx_EXPR_LIST (SImode, gen_rtx_REG (SImode, cum->gprs + 2),
                                         const0_rtx);
          RTVEC_ELT (p, 1)
            = gen_rtx_EXPR_LIST (SImode, gen_rtx_REG (SImode, cum->gprs + 3),
                                         GEN_INT (4));

          return gen_rtx_PARALLEL (mode, p);
        }
    }

  /* After the real arguments, expand_call calls us once again
     with a void_type_node type.  Whatever we return here is
     passed as operand 2 to the call expanders.

     We don't need this feature ...  */
  else if (type == void_type_node)
    return const0_rtx;

  gcc_unreachable ();
}

/* Return true if return values of type TYPE should be returned
   in a memory buffer whose address is passed by the caller as
   hidden first argument.  */

static bool
s390_return_in_memory (const_tree type, const_tree fundecl ATTRIBUTE_UNUSED)
{
  /* We accept small integral (and similar) types.  */
  if (INTEGRAL_TYPE_P (type)
      || POINTER_TYPE_P (type)
      || TREE_CODE (type) == OFFSET_TYPE
      || TREE_CODE (type) == REAL_TYPE)
    return int_size_in_bytes (type) > 8;

  /* Aggregates and similar constructs are always returned
     in memory.  */
  if (AGGREGATE_TYPE_P (type)
      || TREE_CODE (type) == COMPLEX_TYPE
      || TREE_CODE (type) == VECTOR_TYPE)
    return true;

  /* ??? We get called on all sorts of random stuff from
     aggregate_value_p.  We can't abort, but it's not clear
     what's safe to return.  Pretend it's a struct I guess.  */
  return true;
}

/* Function arguments and return values are promoted to word size.  */

static machine_mode
s390_promote_function_mode (const_tree type, machine_mode mode,
                            int *punsignedp,
                            const_tree fntype ATTRIBUTE_UNUSED,
                            int for_return ATTRIBUTE_UNUSED)
{
  if (INTEGRAL_MODE_P (mode)
      && GET_MODE_SIZE (mode) < UNITS_PER_LONG)
    {
      if (type != NULL_TREE && POINTER_TYPE_P (type))
        *punsignedp = POINTERS_EXTEND_UNSIGNED;
      return Pmode;
    }

  return mode;
}

/* Define where to return a (scalar) value of type RET_TYPE.
   If RET_TYPE is null, define where to return a (scalar)
   value of mode MODE from a libcall.  */

static rtx
s390_function_and_libcall_value (machine_mode mode,
                                 const_tree ret_type,
                                 const_tree fntype_or_decl,
                                 bool outgoing ATTRIBUTE_UNUSED)
{
  /* For normal functions perform the promotion as
     promote_function_mode would do.  */
  if (ret_type)
    {
      int unsignedp = TYPE_UNSIGNED (ret_type);
      mode = promote_function_mode (ret_type, mode, &unsignedp,
                                    fntype_or_decl, 1);
    }

  gcc_assert (GET_MODE_CLASS (mode) == MODE_INT || SCALAR_FLOAT_MODE_P (mode));
  gcc_assert (GET_MODE_SIZE (mode) <= 8);

  if (TARGET_HARD_FLOAT && SCALAR_FLOAT_MODE_P (mode))
    return gen_rtx_REG (mode, 16);
  else if (GET_MODE_SIZE (mode) <= UNITS_PER_LONG
           || UNITS_PER_LONG == UNITS_PER_WORD)
    return gen_rtx_REG (mode, 2);
  else if (GET_MODE_SIZE (mode) == 2 * UNITS_PER_LONG)
    {
      /* This case is triggered when returning a 64 bit value with
         -m31 -mzarch.  Although the value would fit into a single
         register it has to be forced into a 32 bit register pair in
         order to match the ABI.  */
      rtvec p = rtvec_alloc (2);

      RTVEC_ELT (p, 0)
        = gen_rtx_EXPR_LIST (SImode, gen_rtx_REG (SImode, 2), const0_rtx);
      RTVEC_ELT (p, 1)
        = gen_rtx_EXPR_LIST (SImode, gen_rtx_REG (SImode, 3), GEN_INT (4));

      return gen_rtx_PARALLEL (mode, p);
    }

  gcc_unreachable ();
}

/* Define where to return a scalar return value of type RET_TYPE.  */

static rtx
s390_function_value (const_tree ret_type, const_tree fn_decl_or_type,
                     bool outgoing)
{
  return s390_function_and_libcall_value (TYPE_MODE (ret_type), ret_type,
                                          fn_decl_or_type, outgoing);
}

/* Define where to return a scalar libcall return value of mode
   MODE.  */

static rtx
s390_libcall_value (machine_mode mode, const_rtx fun ATTRIBUTE_UNUSED)
{
  return s390_function_and_libcall_value (mode, NULL_TREE,
                                          NULL_TREE, true);
}


/* Create and return the va_list datatype.

   On S/390, va_list is an array type equivalent to

      typedef struct __va_list_tag
        {
            long __gpr;
            long __fpr;
            void *__overflow_arg_area;
            void *__reg_save_area;
        } va_list[1];

   where __gpr and __fpr hold the number of general purpose
   or floating point arguments used up to now, respectively,
   __overflow_arg_area points to the stack location of the
   next argument passed on the stack, and __reg_save_area
   always points to the start of the register area in the
   call frame of the current function.  The function prologue
   saves all registers used for argument passing into this
   area if the function uses variable arguments.  */

static tree
s390_build_builtin_va_list (void)
{
  tree f_gpr, f_fpr, f_ovf, f_sav, record, type_decl;

  record = lang_hooks.types.make_type (RECORD_TYPE);

  type_decl =
    build_decl (BUILTINS_LOCATION,
                TYPE_DECL, get_identifier ("__va_list_tag"), record);

  f_gpr = build_decl (BUILTINS_LOCATION,
                      FIELD_DECL, get_identifier ("__gpr"),
                      long_integer_type_node);
  f_fpr = build_decl (BUILTINS_LOCATION,
                      FIELD_DECL, get_identifier ("__fpr"),
                      long_integer_type_node);
  f_ovf = build_decl (BUILTINS_LOCATION,
                      FIELD_DECL, get_identifier ("__overflow_arg_area"),
                      ptr_type_node);
  f_sav = build_decl (BUILTINS_LOCATION,
                      FIELD_DECL, get_identifier ("__reg_save_area"),
                      ptr_type_node);

  va_list_gpr_counter_field = f_gpr;
  va_list_fpr_counter_field = f_fpr;

  DECL_FIELD_CONTEXT (f_gpr) = record;
  DECL_FIELD_CONTEXT (f_fpr) = record;
  DECL_FIELD_CONTEXT (f_ovf) = record;
  DECL_FIELD_CONTEXT (f_sav) = record;

  TYPE_STUB_DECL (record) = type_decl;
  TYPE_NAME (record) = type_decl;
  TYPE_FIELDS (record) = f_gpr;
  DECL_CHAIN (f_gpr) = f_fpr;
  DECL_CHAIN (f_fpr) = f_ovf;
  DECL_CHAIN (f_ovf) = f_sav;

  layout_type (record);

  /* The correct type is an array type of one element.  */
  return build_array_type (record, build_index_type (size_zero_node));
}

/* Implement va_start by filling the va_list structure VALIST.
   STDARG_P is always true, and ignored.
   NEXTARG points to the first anonymous stack argument.

   The following global variables are used to initialize
   the va_list structure:

     crtl->args.info:
       holds number of gprs and fprs used for named arguments.
     crtl->args.arg_offset_rtx:
       holds the offset of the first anonymous stack argument
       (relative to the virtual arg pointer).  */

static void
s390_va_start (tree valist, rtx nextarg ATTRIBUTE_UNUSED)
{
  HOST_WIDE_INT n_gpr, n_fpr;
  int off;
  tree f_gpr, f_fpr, f_ovf, f_sav;
  tree gpr, fpr, ovf, sav, t;

  f_gpr = TYPE_FIELDS (TREE_TYPE (va_list_type_node));
  f_fpr = DECL_CHAIN (f_gpr);
  f_ovf = DECL_CHAIN (f_fpr);
  f_sav = DECL_CHAIN (f_ovf);

  valist = build_simple_mem_ref (valist);
  gpr = build3 (COMPONENT_REF, TREE_TYPE (f_gpr), valist, f_gpr, NULL_TREE);
  fpr = build3 (COMPONENT_REF, TREE_TYPE (f_fpr), valist, f_fpr, NULL_TREE);
  ovf = build3 (COMPONENT_REF, TREE_TYPE (f_ovf), valist, f_ovf, NULL_TREE);
  sav = build3 (COMPONENT_REF, TREE_TYPE (f_sav), valist, f_sav, NULL_TREE);

  /* Count number of gp and fp argument registers used.  */

  n_gpr = crtl->args.info.gprs;
  n_fpr = crtl->args.info.fprs;

  if (cfun->va_list_gpr_size)
    {
      t = build2 (MODIFY_EXPR, TREE_TYPE (gpr), gpr,
                  build_int_cst (NULL_TREE, n_gpr));
      TREE_SIDE_EFFECTS (t) = 1;
      expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);
    }

  if (cfun->va_list_fpr_size)
    {
      t = build2 (MODIFY_EXPR, TREE_TYPE (fpr), fpr,
                  build_int_cst (NULL_TREE, n_fpr));
      TREE_SIDE_EFFECTS (t) = 1;
      expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);
    }

  /* Find the overflow area.  */
  if (n_gpr + cfun->va_list_gpr_size > GP_ARG_NUM_REG
      || n_fpr + cfun->va_list_fpr_size > FP_ARG_NUM_REG)
    {
      t = make_tree (TREE_TYPE (ovf), virtual_incoming_args_rtx);

      off = INTVAL (crtl->args.arg_offset_rtx);
      off = off < 0 ? 0 : off;
      if (TARGET_DEBUG_ARG)
        fprintf (stderr, "va_start: n_gpr = %d, n_fpr = %d off %d\n",
                 (int)n_gpr, (int)n_fpr, off);

      t = fold_build_pointer_plus_hwi (t, off);

      t = build2 (MODIFY_EXPR, TREE_TYPE (ovf), ovf, t);
      TREE_SIDE_EFFECTS (t) = 1;
      expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);
    }

  /* Find the register save area.  */
  if ((cfun->va_list_gpr_size && n_gpr < GP_ARG_NUM_REG)
      || (cfun->va_list_fpr_size && n_fpr < FP_ARG_NUM_REG))
    {
      t = make_tree (TREE_TYPE (sav), return_address_pointer_rtx);
      t = fold_build_pointer_plus_hwi (t, -RETURN_REGNUM * UNITS_PER_LONG);

      t = build2 (MODIFY_EXPR, TREE_TYPE (sav), sav, t);
      TREE_SIDE_EFFECTS (t) = 1;
      expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);
    }
}

/* Implement va_arg by updating the va_list structure
   VALIST as required to retrieve an argument of type
   TYPE, and returning that argument.

   Generates code equivalent to:

   if (integral value) {
     if (size  <= 4 && args.gpr < 5 ||
         size  > 4 && args.gpr < 4 )
       ret = args.reg_save_area[args.gpr+8]
     else
       ret = *args.overflow_arg_area++;
   } else if (float value) {
     if (args.fgpr < 2)
       ret = args.reg_save_area[args.fpr+64]
     else
       ret = *args.overflow_arg_area++;
   } else if (aggregate value) {
     if (args.gpr < 5)
       ret = *args.reg_save_area[args.gpr]
     else
       ret = **args.overflow_arg_area++;
   } */

static tree
s390_gimplify_va_arg (tree valist, tree type, gimple_seq *pre_p,
                      gimple_seq *post_p ATTRIBUTE_UNUSED)
{
  tree f_gpr, f_fpr, f_ovf, f_sav;
  tree gpr, fpr, ovf, sav, reg, t, u;
  int indirect_p, size, n_reg, sav_ofs, sav_scale, max_reg;
  tree lab_false, lab_over, addr;

  f_gpr = TYPE_FIELDS (TREE_TYPE (va_list_type_node));
  f_fpr = DECL_CHAIN (f_gpr);
  f_ovf = DECL_CHAIN (f_fpr);
  f_sav = DECL_CHAIN (f_ovf);

  valist = build_va_arg_indirect_ref (valist);
  gpr = build3 (COMPONENT_REF, TREE_TYPE (f_gpr), valist, f_gpr, NULL_TREE);
  fpr = build3 (COMPONENT_REF, TREE_TYPE (f_fpr), valist, f_fpr, NULL_TREE);
  sav = build3 (COMPONENT_REF, TREE_TYPE (f_sav), valist, f_sav, NULL_TREE);

  /* The tree for args* cannot be shared between gpr/fpr and ovf since
     both appear on a lhs.  */
  valist = unshare_expr (valist);
  ovf = build3 (COMPONENT_REF, TREE_TYPE (f_ovf), valist, f_ovf, NULL_TREE);

  size = int_size_in_bytes (type);

  if (pass_by_reference (NULL, TYPE_MODE (type), type, false))
    {
      if (TARGET_DEBUG_ARG)
        {
          fprintf (stderr, "va_arg: aggregate type");
          debug_tree (type);
        }

      /* Aggregates are passed by reference.  */
      indirect_p = 1;
      reg = gpr;
      n_reg = 1;

      /* kernel stack layout on 31 bit: It is assumed here that no padding
         will be added by s390_frame_info because for va_args always an even
         number of gprs has to be saved r15-r2 = 14 regs.  */
      sav_ofs = 2 * UNITS_PER_LONG;
      sav_scale = UNITS_PER_LONG;
      size = UNITS_PER_LONG;
      max_reg = GP_ARG_NUM_REG - n_reg;
    }
  else if (s390_function_arg_float (TYPE_MODE (type), type))
    {
      if (TARGET_DEBUG_ARG)
        {
          fprintf (stderr, "va_arg: float type");
          debug_tree (type);
        }

      /* FP args go in FP registers, if present.  */
      indirect_p = 0;
      reg = fpr;
      n_reg = 1;
      sav_ofs = 16 * UNITS_PER_LONG;
      sav_scale = 8;
      max_reg = FP_ARG_NUM_REG - n_reg;
    }
  else
    {
      if (TARGET_DEBUG_ARG)
        {
          fprintf (stderr, "va_arg: other type");
          debug_tree (type);
        }

      /* Otherwise into GP registers.  */
      indirect_p = 0;
      reg = gpr;
      n_reg = (size + UNITS_PER_LONG - 1) / UNITS_PER_LONG;

      /* kernel stack layout on 31 bit: It is assumed here that no padding
         will be added by s390_frame_info because for va_args always an even
         number of gprs has to be saved r15-r2 = 14 regs.  */
      sav_ofs = 2 * UNITS_PER_LONG;

      if (size < UNITS_PER_LONG)
        sav_ofs += UNITS_PER_LONG - size;

      sav_scale = UNITS_PER_LONG;
      max_reg = GP_ARG_NUM_REG - n_reg;
    }

  /* Pull the value out of the saved registers ...  */

  lab_false = create_artificial_label (UNKNOWN_LOCATION);
  lab_over = create_artificial_label (UNKNOWN_LOCATION);
  addr = create_tmp_var (ptr_type_node, "addr");

  t = fold_convert (TREE_TYPE (reg), size_int (max_reg));
  t = build2 (GT_EXPR, boolean_type_node, reg, t);
  u = build1 (GOTO_EXPR, void_type_node, lab_false);
  t = build3 (COND_EXPR, void_type_node, t, u, NULL_TREE);
  gimplify_and_add (t, pre_p);

  t = fold_build_pointer_plus_hwi (sav, sav_ofs);
  u = build2 (MULT_EXPR, TREE_TYPE (reg), reg,
              fold_convert (TREE_TYPE (reg), size_int (sav_scale)));
  t = fold_build_pointer_plus (t, u);

  gimplify_assign (addr, t, pre_p);

  gimple_seq_add_stmt (pre_p, gimple_build_goto (lab_over));

  gimple_seq_add_stmt (pre_p, gimple_build_label (lab_false));


  /* ... Otherwise out of the overflow area.  */

  t = ovf;
  if (size < UNITS_PER_LONG)
    t = fold_build_pointer_plus_hwi (t, UNITS_PER_LONG - size);

  gimplify_expr (&t, pre_p, NULL, is_gimple_val, fb_rvalue);

  gimplify_assign (addr, t, pre_p);

  t = fold_build_pointer_plus_hwi (t, size);
  gimplify_assign (ovf, t, pre_p);

  gimple_seq_add_stmt (pre_p, gimple_build_label (lab_over));


  /* Increment register save count.  */

  u = build2 (PREINCREMENT_EXPR, TREE_TYPE (reg), reg,
              fold_convert (TREE_TYPE (reg), size_int (n_reg)));
  gimplify_and_add (u, pre_p);

  if (indirect_p)
    {
      t = build_pointer_type_for_mode (build_pointer_type (type),
                                       ptr_mode, true);
      addr = fold_convert (t, addr);
      addr = build_va_arg_indirect_ref (addr);
    }
  else
    {
      t = build_pointer_type_for_mode (type, ptr_mode, true);
      addr = fold_convert (t, addr);
    }

  return build_va_arg_indirect_ref (addr);
}

/* Emit rtl for the tbegin or tbegin_retry (RETRY != NULL_RTX)
   expanders.
   DEST  - Register location where CC will be stored.
   TDB   - Pointer to a 256 byte area where to store the transaction.
           diagnostic block. NULL if TDB is not needed.
   RETRY - Retry count value.  If non-NULL a retry loop for CC2
           is emitted
   CLOBBER_FPRS_P - If true clobbers for all FPRs are emitted as part
                    of the tbegin instruction pattern.  */

void
s390_expand_tbegin (rtx dest, rtx tdb, rtx retry, bool clobber_fprs_p)
{
  rtx retry_plus_two = gen_reg_rtx (SImode);
  rtx retry_reg = gen_reg_rtx (SImode);
  rtx_code_label *retry_label = NULL;

  if (retry != NULL_RTX)
    {
      emit_move_insn (retry_reg, retry);
      emit_insn (gen_addsi3 (retry_plus_two, retry_reg, const2_rtx));
      emit_insn (gen_addsi3 (retry_reg, retry_reg, const1_rtx));
      retry_label = gen_label_rtx ();
      emit_label (retry_label);
    }

  if (clobber_fprs_p)
    emit_insn (gen_tbegin_1 (gen_rtx_CONST_INT (VOIDmode, TBEGIN_MASK), tdb));
  else
    emit_insn (gen_tbegin_nofloat_1 (gen_rtx_CONST_INT (VOIDmode, TBEGIN_MASK),
                                     tdb));

  emit_move_insn (dest, gen_rtx_UNSPEC (SImode,
                                        gen_rtvec (1, gen_rtx_REG (CCRAWmode,
                                                                   CC_REGNUM)),
                                        UNSPEC_CC_TO_INT));
  if (retry != NULL_RTX)
    {
      const int CC0 = 1 << 3;
      const int CC1 = 1 << 2;
      const int CC3 = 1 << 0;
      rtx jump;
      rtx count = gen_reg_rtx (SImode);
      rtx_code_label *leave_label = gen_label_rtx ();

      /* Exit for success and permanent failures.  */
      jump = s390_emit_jump (leave_label,
                             gen_rtx_EQ (VOIDmode,
                               gen_rtx_REG (CCRAWmode, CC_REGNUM),
                               gen_rtx_CONST_INT (VOIDmode, CC0 | CC1 | CC3)));
      LABEL_NUSES (leave_label) = 1;

      /* CC2 - transient failure. Perform retry with ppa.  */
      emit_move_insn (count, retry_plus_two);
      emit_insn (gen_subsi3 (count, count, retry_reg));
      emit_insn (gen_tx_assist (count));
      jump = emit_jump_insn (gen_doloop_si64 (retry_label,
                                              retry_reg,
                                              retry_reg));
      JUMP_LABEL (jump) = retry_label;
      LABEL_NUSES (retry_label) = 1;
      emit_label (leave_label);
    }
}

/* Builtins.  */

enum s390_builtin
{
  S390_BUILTIN_TBEGIN,
  S390_BUILTIN_TBEGIN_NOFLOAT,
  S390_BUILTIN_TBEGIN_RETRY,
  S390_BUILTIN_TBEGIN_RETRY_NOFLOAT,
  S390_BUILTIN_TBEGINC,
  S390_BUILTIN_TEND,
  S390_BUILTIN_TABORT,
  S390_BUILTIN_NON_TX_STORE,
  S390_BUILTIN_TX_NESTING_DEPTH,
  S390_BUILTIN_TX_ASSIST,

  S390_BUILTIN_max
};

static enum insn_code const code_for_builtin[S390_BUILTIN_max] = {
  CODE_FOR_tbegin,
  CODE_FOR_tbegin_nofloat,
  CODE_FOR_tbegin_retry,
  CODE_FOR_tbegin_retry_nofloat,
  CODE_FOR_tbeginc,
  CODE_FOR_tend,
  CODE_FOR_tabort,
  CODE_FOR_ntstg,
  CODE_FOR_etnd,
  CODE_FOR_tx_assist
};

static void
s390_init_builtins (void)
{
  tree ftype, uint64_type;
  tree returns_twice_attr = tree_cons (get_identifier ("returns_twice"),
                                       NULL, NULL);
  tree noreturn_attr = tree_cons (get_identifier ("noreturn"), NULL, NULL);

  /* void foo (void) */
  ftype = build_function_type_list (void_type_node, NULL_TREE);
  add_builtin_function ("__builtin_tbeginc", ftype, S390_BUILTIN_TBEGINC,
                        BUILT_IN_MD, NULL, NULL_TREE);

  /* void foo (int) */
  ftype = build_function_type_list (void_type_node, integer_type_node,
                                    NULL_TREE);
  add_builtin_function ("__builtin_tabort", ftype,
                        S390_BUILTIN_TABORT, BUILT_IN_MD, NULL, noreturn_attr);
  add_builtin_function ("__builtin_tx_assist", ftype,
                        S390_BUILTIN_TX_ASSIST, BUILT_IN_MD, NULL, NULL_TREE);

  /* int foo (void *) */
  ftype = build_function_type_list (integer_type_node, ptr_type_node, NULL_TREE);
  add_builtin_function ("__builtin_tbegin", ftype, S390_BUILTIN_TBEGIN,
                        BUILT_IN_MD, NULL, returns_twice_attr);
  add_builtin_function ("__builtin_tbegin_nofloat", ftype,
                        S390_BUILTIN_TBEGIN_NOFLOAT,
                        BUILT_IN_MD, NULL, returns_twice_attr);

  /* int foo (void *, int) */
  ftype = build_function_type_list (integer_type_node, ptr_type_node,
                                    integer_type_node, NULL_TREE);
  add_builtin_function ("__builtin_tbegin_retry", ftype,
                        S390_BUILTIN_TBEGIN_RETRY,
                        BUILT_IN_MD,
                        NULL, returns_twice_attr);
  add_builtin_function ("__builtin_tbegin_retry_nofloat", ftype,
                        S390_BUILTIN_TBEGIN_RETRY_NOFLOAT,
                        BUILT_IN_MD,
                        NULL, returns_twice_attr);

  /* int foo (void) */
  ftype = build_function_type_list (integer_type_node, NULL_TREE);
  add_builtin_function ("__builtin_tx_nesting_depth", ftype,
                        S390_BUILTIN_TX_NESTING_DEPTH,
                        BUILT_IN_MD, NULL, NULL_TREE);
  add_builtin_function ("__builtin_tend", ftype,
                        S390_BUILTIN_TEND, BUILT_IN_MD, NULL, NULL_TREE);

  /* void foo (uint64_t *, uint64_t) */
  if (TARGET_64BIT)
    uint64_type = long_unsigned_type_node;
  else
    uint64_type = long_long_unsigned_type_node;

   ftype = build_function_type_list (void_type_node,
                                    build_pointer_type (uint64_type),
                                    uint64_type, NULL_TREE);
  add_builtin_function ("__builtin_non_tx_store", ftype,
                        S390_BUILTIN_NON_TX_STORE,
                        BUILT_IN_MD, NULL, NULL_TREE);
}

/* Expand an expression EXP that calls a built-in function,
   with result going to TARGET if that's convenient
   (and in mode MODE if that's convenient).
   SUBTARGET may be used as the target for computing one of EXP's operands.
   IGNORE is nonzero if the value is to be ignored.  */

static rtx
s390_expand_builtin (tree exp, rtx target, rtx subtarget ATTRIBUTE_UNUSED,
                     machine_mode mode ATTRIBUTE_UNUSED,
                     int ignore ATTRIBUTE_UNUSED)
{
#define MAX_ARGS 2

  tree fndecl = TREE_OPERAND (CALL_EXPR_FN (exp), 0);
  unsigned int fcode = DECL_FUNCTION_CODE (fndecl);
  enum insn_code icode;
  rtx op[MAX_ARGS], pat;
  int arity;
  bool nonvoid;
  tree arg;
  call_expr_arg_iterator iter;

  if (fcode >= S390_BUILTIN_max)
    internal_error ("bad builtin fcode");
  icode = code_for_builtin[fcode];
  if (icode == 0)
    internal_error ("bad builtin fcode");

  if (!TARGET_HTM)
    error ("Transactional execution builtins not enabled (-mhtm)\n");

  /* Set a flag in the machine specific cfun part in order to support
     saving/restoring of FPRs.  */
  if (fcode == S390_BUILTIN_TBEGIN || fcode == S390_BUILTIN_TBEGIN_RETRY)
    cfun->machine->tbegin_p = true;

  nonvoid = TREE_TYPE (TREE_TYPE (fndecl)) != void_type_node;

  arity = 0;
  FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
    {
      const struct insn_operand_data *insn_op;

      if (arg == error_mark_node)
        return NULL_RTX;
      if (arity >= MAX_ARGS)
        return NULL_RTX;

      insn_op = &insn_data[icode].operand[arity + nonvoid];

      op[arity] = expand_expr (arg, NULL_RTX, insn_op->mode, EXPAND_NORMAL);

      if (!(*insn_op->predicate) (op[arity], insn_op->mode))
        {
          if (insn_op->predicate == memory_operand)
            {
              /* Don't move a NULL pointer into a register. Otherwise
                 we have to rely on combine being able to move it back
                 in order to get an immediate 0 in the instruction.  */
              if (op[arity] != const0_rtx)
                op[arity] = copy_to_mode_reg (Pmode, op[arity]);
              op[arity] = gen_rtx_MEM (insn_op->mode, op[arity]);
            }
          else
            op[arity] = copy_to_mode_reg (insn_op->mode, op[arity]);
        }

      arity++;
    }

  if (nonvoid)
    {
      machine_mode tmode = insn_data[icode].operand[0].mode;
      if (!target
          || GET_MODE (target) != tmode
          || !(*insn_data[icode].operand[0].predicate) (target, tmode))
        target = gen_reg_rtx (tmode);
    }

  switch (arity)
    {
    case 0:
      pat = GEN_FCN (icode) (target);
      break;
    case 1:
      if (nonvoid)
        pat = GEN_FCN (icode) (target, op[0]);
      else
        pat = GEN_FCN (icode) (op[0]);
      break;
    case 2:
      if (nonvoid)
        pat = GEN_FCN (icode) (target, op[0], op[1]);
      else
        pat = GEN_FCN (icode) (op[0], op[1]);
      break;
    default:
      gcc_unreachable ();
    }
  if (!pat)
    return NULL_RTX;
  emit_insn (pat);

  if (nonvoid)
    return target;
  else
    return const0_rtx;
}

/* We call mcount before the function prologue.  So a profiled leaf
   function should stay a leaf function.  */

static bool
s390_keep_leaf_when_profiled ()
{
  return true;
}

/* Output assembly code for the trampoline template to
   stdio stream FILE.

   On S/390, we use gpr 1 internally in the trampoline code;
   gpr 0 is used to hold the static chain.  */

static void
s390_asm_trampoline_template (FILE *file)
{
  rtx op[2];
  op[0] = gen_rtx_REG (Pmode, 0);
  op[1] = gen_rtx_REG (Pmode, 1);

  if (TARGET_64BIT)
    {
      output_asm_insn ("basr\t%1,0", op);         /* 2 byte */
      output_asm_insn ("lmg\t%0,%1,14(%1)", op);  /* 6 byte */
      output_asm_insn ("br\t%1", op);             /* 2 byte */
      ASM_OUTPUT_SKIP (file, (HOST_WIDE_INT)(TRAMPOLINE_SIZE - 10));
    }
  else
    {
      output_asm_insn ("basr\t%1,0", op);         /* 2 byte */
      output_asm_insn ("lm\t%0,%1,6(%1)", op);    /* 4 byte */
      output_asm_insn ("br\t%1", op);             /* 2 byte */
      ASM_OUTPUT_SKIP (file, (HOST_WIDE_INT)(TRAMPOLINE_SIZE - 8));
    }
}

/* Emit RTL insns to initialize the variable parts of a trampoline.
   FNADDR is an RTX for the address of the function's pure code.
   CXT is an RTX for the static chain value for the function.  */

static void
s390_trampoline_init (rtx m_tramp, tree fndecl, rtx cxt)
{
  rtx fnaddr = XEXP (DECL_RTL (fndecl), 0);
  rtx mem;

  emit_block_move (m_tramp, assemble_trampoline_template (),
                   GEN_INT (2 * UNITS_PER_LONG), BLOCK_OP_NORMAL);

  mem = adjust_address (m_tramp, Pmode, 2 * UNITS_PER_LONG);
  emit_move_insn (mem, cxt);
  mem = adjust_address (m_tramp, Pmode, 3 * UNITS_PER_LONG);
  emit_move_insn (mem, fnaddr);
}

/* Output assembler code to FILE to increment profiler label # LABELNO
   for profiling a function entry.  */

void
s390_function_profiler (FILE *file, int labelno)
{
  rtx op[7];

  char label[128];
  ASM_GENERATE_INTERNAL_LABEL (label, "LP", labelno);

  fprintf (file, "# function profiler \n");

  op[0] = gen_rtx_REG (Pmode, RETURN_REGNUM);
  op[1] = gen_rtx_REG (Pmode, STACK_POINTER_REGNUM);
  op[1] = gen_rtx_MEM (Pmode, plus_constant (Pmode, op[1], UNITS_PER_LONG));

  op[2] = gen_rtx_REG (Pmode, 1);
  op[3] = gen_rtx_SYMBOL_REF (Pmode, label);
  SYMBOL_REF_FLAGS (op[3]) = SYMBOL_FLAG_LOCAL;

  op[4] = gen_rtx_SYMBOL_REF (Pmode, "_mcount");
  if (flag_pic)
    {
      op[4] = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, op[4]), UNSPEC_PLT);
      op[4] = gen_rtx_CONST (Pmode, op[4]);
    }

  if (TARGET_64BIT)
    {
      output_asm_insn ("stg\t%0,%1", op);
      output_asm_insn ("larl\t%2,%3", op);
      output_asm_insn ("brasl\t%0,%4", op);
      output_asm_insn ("lg\t%0,%1", op);
    }
  else if (!flag_pic)
    {
      op[6] = gen_label_rtx ();

      output_asm_insn ("st\t%0,%1", op);
      output_asm_insn ("bras\t%2,%l6", op);
      output_asm_insn (".long\t%4", op);
      output_asm_insn (".long\t%3", op);
      targetm.asm_out.internal_label (file, "L", CODE_LABEL_NUMBER (op[6]));
      output_asm_insn ("l\t%0,0(%2)", op);
      output_asm_insn ("l\t%2,4(%2)", op);
      output_asm_insn ("basr\t%0,%0", op);
      output_asm_insn ("l\t%0,%1", op);
    }
  else
    {
      op[5] = gen_label_rtx ();
      op[6] = gen_label_rtx ();

      output_asm_insn ("st\t%0,%1", op);
      output_asm_insn ("bras\t%2,%l6", op);
      targetm.asm_out.internal_label (file, "L", CODE_LABEL_NUMBER (op[5]));
      output_asm_insn (".long\t%4-%l5", op);
      output_asm_insn (".long\t%3-%l5", op);
      targetm.asm_out.internal_label (file, "L", CODE_LABEL_NUMBER (op[6]));
      output_asm_insn ("lr\t%0,%2", op);
      output_asm_insn ("a\t%0,0(%2)", op);
      output_asm_insn ("a\t%2,4(%2)", op);
      output_asm_insn ("basr\t%0,%0", op);
      output_asm_insn ("l\t%0,%1", op);
    }
}

/* Encode symbol attributes (local vs. global, tls model) of a SYMBOL_REF
   into its SYMBOL_REF_FLAGS.  */

static void
s390_encode_section_info (tree decl, rtx rtl, int first)
{
  default_encode_section_info (decl, rtl, first);

  if (TREE_CODE (decl) == VAR_DECL)
    {
      /* If a variable has a forced alignment to < 2 bytes, mark it
         with SYMBOL_FLAG_ALIGN1 to prevent it from being used as LARL
         operand.  */
      if (DECL_USER_ALIGN (decl) && DECL_ALIGN (decl) < 16)
        SYMBOL_REF_FLAGS (XEXP (rtl, 0)) |= SYMBOL_FLAG_ALIGN1;
      if (!DECL_SIZE (decl)
          || !DECL_ALIGN (decl)
          || !tree_fits_shwi_p (DECL_SIZE (decl))
          || (DECL_ALIGN (decl) <= 64
              && DECL_ALIGN (decl) != tree_to_shwi (DECL_SIZE (decl))))
        SYMBOL_REF_FLAGS (XEXP (rtl, 0)) |= SYMBOL_FLAG_NOT_NATURALLY_ALIGNED;
    }

  /* Literal pool references don't have a decl so they are handled
     differently here.  We rely on the information in the MEM_ALIGN
     entry to decide upon natural alignment.  */
  if (MEM_P (rtl)
      && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
      && TREE_CONSTANT_POOL_ADDRESS_P (XEXP (rtl, 0))
      && (MEM_ALIGN (rtl) == 0
          || GET_MODE_BITSIZE (GET_MODE (rtl)) == 0
          || MEM_ALIGN (rtl) < GET_MODE_BITSIZE (GET_MODE (rtl))))
    SYMBOL_REF_FLAGS (XEXP (rtl, 0)) |= SYMBOL_FLAG_NOT_NATURALLY_ALIGNED;
}

/* Output thunk to FILE that implements a C++ virtual function call (with
   multiple inheritance) to FUNCTION.  The thunk adjusts the this pointer
   by DELTA, and unless VCALL_OFFSET is zero, applies an additional adjustment
   stored at VCALL_OFFSET in the vtable whose address is located at offset 0
   relative to the resulting this pointer.  */

static void
s390_output_mi_thunk (FILE *file, tree thunk ATTRIBUTE_UNUSED,
                      HOST_WIDE_INT delta, HOST_WIDE_INT vcall_offset,
                      tree function)
{
  rtx op[10];
  int nonlocal = 0;

  /* Make sure unwind info is emitted for the thunk if needed.  */
  final_start_function (emit_barrier (), file, 1);

  /* Operand 0 is the target function.  */
  op[0] = XEXP (DECL_RTL (function), 0);
  if (flag_pic && !SYMBOL_REF_LOCAL_P (op[0]))
    {
      nonlocal = 1;
      op[0] = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, op[0]),
                              TARGET_64BIT ? UNSPEC_PLT : UNSPEC_GOT);
      op[0] = gen_rtx_CONST (Pmode, op[0]);
    }

  /* Operand 1 is the 'this' pointer.  */
  if (aggregate_value_p (TREE_TYPE (TREE_TYPE (function)), function))
    op[1] = gen_rtx_REG (Pmode, 3);
  else
    op[1] = gen_rtx_REG (Pmode, 2);

  /* Operand 2 is the delta.  */
  op[2] = GEN_INT (delta);

  /* Operand 3 is the vcall_offset.  */
  op[3] = GEN_INT (vcall_offset);

  /* Operand 4 is the temporary register.  */
  op[4] = gen_rtx_REG (Pmode, 1);

  /* Operands 5 to 8 can be used as labels.  */
  op[5] = NULL_RTX;
  op[6] = NULL_RTX;
  op[7] = NULL_RTX;
  op[8] = NULL_RTX;

  /* Operand 9 can be used for temporary register.  */
  op[9] = NULL_RTX;

  /* Generate code.  */
  if (TARGET_64BIT)
    {
      /* Setup literal pool pointer if required.  */
      if ((!DISP_IN_RANGE (delta)
           && !CONST_OK_FOR_K (delta)
           && !CONST_OK_FOR_Os (delta))
          || (!DISP_IN_RANGE (vcall_offset)
              && !CONST_OK_FOR_K (vcall_offset)
              && !CONST_OK_FOR_Os (vcall_offset)))
        {
          op[5] = gen_label_rtx ();
          output_asm_insn ("larl\t%4,%5", op);
        }

      /* Add DELTA to this pointer.  */
      if (delta)
        {
          if (CONST_OK_FOR_J (delta))
            output_asm_insn ("la\t%1,%2(%1)", op);
          else if (DISP_IN_RANGE (delta))
            output_asm_insn ("lay\t%1,%2(%1)", op);
          else if (CONST_OK_FOR_K (delta))
            output_asm_insn ("aghi\t%1,%2", op);
          else if (CONST_OK_FOR_Os (delta))
            output_asm_insn ("agfi\t%1,%2", op);
          else
            {
              op[6] = gen_label_rtx ();
              output_asm_insn ("agf\t%1,%6-%5(%4)", op);
            }
        }

      /* Perform vcall adjustment.  */
      if (vcall_offset)
        {
          if (DISP_IN_RANGE (vcall_offset))
            {
              output_asm_insn ("lg\t%4,0(%1)", op);
              output_asm_insn ("ag\t%1,%3(%4)", op);
            }
          else if (CONST_OK_FOR_K (vcall_offset))
            {
              output_asm_insn ("lghi\t%4,%3", op);
              output_asm_insn ("ag\t%4,0(%1)", op);
              output_asm_insn ("ag\t%1,0(%4)", op);
            }
          else if (CONST_OK_FOR_Os (vcall_offset))
            {
              output_asm_insn ("lgfi\t%4,%3", op);
              output_asm_insn ("ag\t%4,0(%1)", op);
              output_asm_insn ("ag\t%1,0(%4)", op);
            }
          else
            {
              op[7] = gen_label_rtx ();
              output_asm_insn ("llgf\t%4,%7-%5(%4)", op);
              output_asm_insn ("ag\t%4,0(%1)", op);
              output_asm_insn ("ag\t%1,0(%4)", op);
            }
        }

      /* Jump to target.  */
      output_asm_insn ("jg\t%0", op);

      /* Output literal pool if required.  */
      if (op[5])
        {
          output_asm_insn (".align\t4", op);
          targetm.asm_out.internal_label (file, "L",
                                          CODE_LABEL_NUMBER (op[5]));
        }
      if (op[6])
        {
          targetm.asm_out.internal_label (file, "L",
                                          CODE_LABEL_NUMBER (op[6]));
          output_asm_insn (".long\t%2", op);
        }
      if (op[7])
        {
          targetm.asm_out.internal_label (file, "L",
                                          CODE_LABEL_NUMBER (op[7]));
          output_asm_insn (".long\t%3", op);
        }
    }
  else
    {
      /* Setup base pointer if required.  */
      if (!vcall_offset
          || (!DISP_IN_RANGE (delta)
              && !CONST_OK_FOR_K (delta)
              && !CONST_OK_FOR_Os (delta))
          || (!DISP_IN_RANGE (delta)
              && !CONST_OK_FOR_K (vcall_offset)
              && !CONST_OK_FOR_Os (vcall_offset)))
        {
          op[5] = gen_label_rtx ();
          output_asm_insn ("basr\t%4,0", op);
          targetm.asm_out.internal_label (file, "L",
                                          CODE_LABEL_NUMBER (op[5]));
        }

      /* Add DELTA to this pointer.  */
      if (delta)
        {
          if (CONST_OK_FOR_J (delta))
            output_asm_insn ("la\t%1,%2(%1)", op);
          else if (DISP_IN_RANGE (delta))
            output_asm_insn ("lay\t%1,%2(%1)", op);
          else if (CONST_OK_FOR_K (delta))
            output_asm_insn ("ahi\t%1,%2", op);
          else if (CONST_OK_FOR_Os (delta))
            output_asm_insn ("afi\t%1,%2", op);
          else
            {
              op[6] = gen_label_rtx ();
              output_asm_insn ("a\t%1,%6-%5(%4)", op);
            }
        }

      /* Perform vcall adjustment.  */
      if (vcall_offset)
        {
          if (CONST_OK_FOR_J (vcall_offset))
            {
              output_asm_insn ("l\t%4,0(%1)", op);
              output_asm_insn ("a\t%1,%3(%4)", op);
            }
          else if (DISP_IN_RANGE (vcall_offset))
            {
              output_asm_insn ("l\t%4,0(%1)", op);
              output_asm_insn ("ay\t%1,%3(%4)", op);
            }
          else if (CONST_OK_FOR_K (vcall_offset))
            {
              output_asm_insn ("lhi\t%4,%3", op);
              output_asm_insn ("a\t%4,0(%1)", op);
              output_asm_insn ("a\t%1,0(%4)", op);
            }
          else if (CONST_OK_FOR_Os (vcall_offset))
            {
              output_asm_insn ("iilf\t%4,%3", op);
              output_asm_insn ("a\t%4,0(%1)", op);
              output_asm_insn ("a\t%1,0(%4)", op);
            }
          else
            {
              op[7] = gen_label_rtx ();
              output_asm_insn ("l\t%4,%7-%5(%4)", op);
              output_asm_insn ("a\t%4,0(%1)", op);
              output_asm_insn ("a\t%1,0(%4)", op);
            }

          /* We had to clobber the base pointer register.
             Re-setup the base pointer (with a different base).  */
          op[5] = gen_label_rtx ();
          output_asm_insn ("basr\t%4,0", op);
          targetm.asm_out.internal_label (file, "L",
                                          CODE_LABEL_NUMBER (op[5]));
        }

      /* Jump to target.  */
      op[8] = gen_label_rtx ();

      if (!flag_pic)
        output_asm_insn ("l\t%4,%8-%5(%4)", op);
      else if (!nonlocal)
        output_asm_insn ("a\t%4,%8-%5(%4)", op);
      /* We cannot call through .plt, since .plt requires %r12 loaded.  */
      else if (flag_pic == 1)
        {
          output_asm_insn ("a\t%4,%8-%5(%4)", op);
          output_asm_insn ("l\t%4,%0(%4)", op);
        }
      else if (flag_pic == 2)
        {
          op[9] = gen_rtx_REG (Pmode, 0);
          output_asm_insn ("l\t%9,%8-4-%5(%4)", op);
          output_asm_insn ("a\t%4,%8-%5(%4)", op);
          output_asm_insn ("ar\t%4,%9", op);
          output_asm_insn ("l\t%4,0(%4)", op);
        }

      output_asm_insn ("br\t%4", op);

      /* Output literal pool.  */
      output_asm_insn (".align\t4", op);

      if (nonlocal && flag_pic == 2)
        output_asm_insn (".long\t%0", op);
      if (nonlocal)
        {
          op[0] = gen_rtx_SYMBOL_REF (Pmode, "_GLOBAL_OFFSET_TABLE_");
          SYMBOL_REF_FLAGS (op[0]) = SYMBOL_FLAG_LOCAL;
        }

      targetm.asm_out.internal_label (file, "L", CODE_LABEL_NUMBER (op[8]));
      if (!flag_pic)
        output_asm_insn (".long\t%0", op);
      else
        output_asm_insn (".long\t%0-%5", op);

      if (op[6])
        {
          targetm.asm_out.internal_label (file, "L",
                                          CODE_LABEL_NUMBER (op[6]));
          output_asm_insn (".long\t%2", op);
        }
      if (op[7])
        {
          targetm.asm_out.internal_label (file, "L",
                                          CODE_LABEL_NUMBER (op[7]));
          output_asm_insn (".long\t%3", op);
        }
    }
  final_end_function ();
}

static bool
s390_valid_pointer_mode (machine_mode mode)
{
  return (mode == SImode || (TARGET_64BIT && mode == DImode));
}

/* Checks whether the given CALL_EXPR would use a caller
   saved register.  This is used to decide whether sibling call
   optimization could be performed on the respective function
   call.  */

static bool
s390_call_saved_register_used (tree call_expr)
{
  CUMULATIVE_ARGS cum_v;
  cumulative_args_t cum;
  tree parameter;
  machine_mode mode;
  tree type;
  rtx parm_rtx;
  int reg, i;

  INIT_CUMULATIVE_ARGS (cum_v, NULL, NULL, 0, 0);
  cum = pack_cumulative_args (&cum_v);

  for (i = 0; i < call_expr_nargs (call_expr); i++)
    {
      parameter = CALL_EXPR_ARG (call_expr, i);
      gcc_assert (parameter);

      /* For an undeclared variable passed as parameter we will get
         an ERROR_MARK node here.  */
      if (TREE_CODE (parameter) == ERROR_MARK)
        return true;

      type = TREE_TYPE (parameter);
      gcc_assert (type);

      mode = TYPE_MODE (type);
      gcc_assert (mode);

      if (pass_by_reference (&cum_v, mode, type, true))
        {
          mode = Pmode;
          type = build_pointer_type (type);
        }

       parm_rtx = s390_function_arg (cum, mode, type, 0);

       s390_function_arg_advance (cum, mode, type, 0);

       if (!parm_rtx)
         continue;

       if (REG_P (parm_rtx))
         {
           for (reg = 0;
                reg < HARD_REGNO_NREGS (REGNO (parm_rtx), GET_MODE (parm_rtx));
                reg++)
             if (!call_used_regs[reg + REGNO (parm_rtx)])
               return true;
         }

       if (GET_CODE (parm_rtx) == PARALLEL)
         {
           int i;

           for (i = 0; i < XVECLEN (parm_rtx, 0); i++)
             {
               rtx r = XEXP (XVECEXP (parm_rtx, 0, i), 0);

               gcc_assert (REG_P (r));

               for (reg = 0;
                    reg < HARD_REGNO_NREGS (REGNO (r), GET_MODE (r));
                    reg++)
                 if (!call_used_regs[reg + REGNO (r)])
                   return true;
             }
         }

    }
  return false;
}

/* Return true if the given call expression can be
   turned into a sibling call.
   DECL holds the declaration of the function to be called whereas
   EXP is the call expression itself.  */

static bool
s390_function_ok_for_sibcall (tree decl, tree exp)
{
  /* The TPF epilogue uses register 1.  */
  if (TARGET_TPF_PROFILING)
    return false;

  /* The 31 bit PLT code uses register 12 (GOT pointer - caller saved)
     which would have to be restored before the sibcall.  */
  if (!TARGET_64BIT && flag_pic && decl && !targetm.binds_local_p (decl))
    return false;

  /* Register 6 on s390 is available as an argument register but unfortunately
     "caller saved". This makes functions needing this register for arguments
     not suitable for sibcalls.  */
  return !s390_call_saved_register_used (exp);
}

/* Return the fixed registers used for condition codes.  */

static bool
s390_fixed_condition_code_regs (unsigned int *p1, unsigned int *p2)
{
  *p1 = CC_REGNUM;
  *p2 = INVALID_REGNUM;

  return true;
}

/* This function is used by the call expanders of the machine description.
   It emits the call insn itself together with the necessary operations
   to adjust the target address and returns the emitted insn.
   ADDR_LOCATION is the target address rtx
   TLS_CALL the location of the thread-local symbol
   RESULT_REG the register where the result of the call should be stored
   RETADDR_REG the register where the return address should be stored
               If this parameter is NULL_RTX the call is considered
               to be a sibling call.  */

rtx_insn *
s390_emit_call (rtx addr_location, rtx tls_call, rtx result_reg,
                rtx retaddr_reg)
{
  bool plt_call = false;
  rtx_insn *insn;
  rtx call;
  rtx clobber;
  rtvec vec;

  /* Direct function calls need special treatment.  */
  if (GET_CODE (addr_location) == SYMBOL_REF)
    {
      /* When calling a global routine in PIC mode, we must
         replace the symbol itself with the PLT stub.  */
      if (flag_pic && !SYMBOL_REF_LOCAL_P (addr_location))
        {
          if (retaddr_reg != NULL_RTX)
            {
              addr_location = gen_rtx_UNSPEC (Pmode,
                                              gen_rtvec (1, addr_location),
                                              UNSPEC_PLT);
              addr_location = gen_rtx_CONST (Pmode, addr_location);
              plt_call = true;
            }
          else
            /* For -fpic code the PLT entries might use r12 which is
               call-saved.  Therefore we cannot do a sibcall when
               calling directly using a symbol ref.  When reaching
               this point we decided (in s390_function_ok_for_sibcall)
               to do a sibcall for a function pointer but one of the
               optimizers was able to get rid of the function pointer
               by propagating the symbol ref into the call.  This
               optimization is illegal for S/390 so we turn the direct
               call into a indirect call again.  */
            addr_location = force_reg (Pmode, addr_location);
        }

      /* Unless we can use the bras(l) insn, force the
         routine address into a register.  */
      if (!TARGET_SMALL_EXEC && !TARGET_CPU_ZARCH)
        {
          if (flag_pic)
            addr_location = legitimize_pic_address (addr_location, 0);
          else
            addr_location = force_reg (Pmode, addr_location);
        }
    }

  /* If it is already an indirect call or the code above moved the
     SYMBOL_REF to somewhere else make sure the address can be found in
     register 1.  */
  if (retaddr_reg == NULL_RTX
      && GET_CODE (addr_location) != SYMBOL_REF
      && !plt_call)
    {
      emit_move_insn (gen_rtx_REG (Pmode, SIBCALL_REGNUM), addr_location);
      addr_location = gen_rtx_REG (Pmode, SIBCALL_REGNUM);
    }

  addr_location = gen_rtx_MEM (QImode, addr_location);
  call = gen_rtx_CALL (VOIDmode, addr_location, const0_rtx);

  if (result_reg != NULL_RTX)
    call = gen_rtx_SET (VOIDmode, result_reg, call);

  if (retaddr_reg != NULL_RTX)
    {
      clobber = gen_rtx_CLOBBER (VOIDmode, retaddr_reg);

      if (tls_call != NULL_RTX)
        vec = gen_rtvec (3, call, clobber,
                         gen_rtx_USE (VOIDmode, tls_call));
      else
        vec = gen_rtvec (2, call, clobber);

      call = gen_rtx_PARALLEL (VOIDmode, vec);
    }

  insn = emit_call_insn (call);

  /* 31-bit PLT stubs and tls calls use the GOT register implicitly.  */
  if ((!TARGET_64BIT && plt_call) || tls_call != NULL_RTX)
    {
      /* s390_function_ok_for_sibcall should
         have denied sibcalls in this case.  */
      gcc_assert (retaddr_reg != NULL_RTX);
      use_reg (&CALL_INSN_FUNCTION_USAGE (insn), gen_rtx_REG (Pmode, 12));
    }
  return insn;
}

/* Implement TARGET_CONDITIONAL_REGISTER_USAGE.  */

static void
s390_conditional_register_usage (void)
{
  int i;

  if (flag_pic)
    {
      fixed_regs[PIC_OFFSET_TABLE_REGNUM] = 1;
      call_used_regs[PIC_OFFSET_TABLE_REGNUM] = 1;
    }
  if (TARGET_CPU_ZARCH)
    {
      fixed_regs[BASE_REGNUM] = 0;
      call_used_regs[BASE_REGNUM] = 0;
      fixed_regs[RETURN_REGNUM] = 0;
      call_used_regs[RETURN_REGNUM] = 0;
    }
  if (TARGET_64BIT)
    {
      for (i = FPR8_REGNUM; i <= FPR15_REGNUM; i++)
        call_used_regs[i] = call_really_used_regs[i] = 0;
    }
  else
    {
      call_used_regs[FPR4_REGNUM] = call_really_used_regs[FPR4_REGNUM] = 0;
      call_used_regs[FPR6_REGNUM] = call_really_used_regs[FPR6_REGNUM] = 0;
    }

  if (TARGET_SOFT_FLOAT)
    {
      for (i = FPR0_REGNUM; i <= FPR15_REGNUM; i++)
        call_used_regs[i] = fixed_regs[i] = 1;
    }
}

/* Corresponding function to eh_return expander.  */

static GTY(()) rtx s390_tpf_eh_return_symbol;
void
s390_emit_tpf_eh_return (rtx target)
{
  rtx_insn *insn;
  rtx reg, orig_ra;

  if (!s390_tpf_eh_return_symbol)
    s390_tpf_eh_return_symbol = gen_rtx_SYMBOL_REF (Pmode, "__tpf_eh_return");

  reg = gen_rtx_REG (Pmode, 2);
  orig_ra = gen_rtx_REG (Pmode, 3);

  emit_move_insn (reg, target);
  emit_move_insn (orig_ra, get_hard_reg_initial_val (Pmode, RETURN_REGNUM));
  insn = s390_emit_call (s390_tpf_eh_return_symbol, NULL_RTX, reg,
                                     gen_rtx_REG (Pmode, RETURN_REGNUM));
  use_reg (&CALL_INSN_FUNCTION_USAGE (insn), reg);
  use_reg (&CALL_INSN_FUNCTION_USAGE (insn), orig_ra);

  emit_move_insn (EH_RETURN_HANDLER_RTX, reg);
}

/* Rework the prologue/epilogue to avoid saving/restoring
   registers unnecessarily.  */

static void
s390_optimize_prologue (void)
{
  rtx_insn *insn, *new_insn, *next_insn;

  /* Do a final recompute of the frame-related data.  */
  s390_optimize_register_info ();

  /* If all special registers are in fact used, there's nothing we
     can do, so no point in walking the insn list.  */

  if (cfun_frame_layout.first_save_gpr <= BASE_REGNUM
      && cfun_frame_layout.last_save_gpr >= BASE_REGNUM
      && (TARGET_CPU_ZARCH
          || (cfun_frame_layout.first_save_gpr <= RETURN_REGNUM
              && cfun_frame_layout.last_save_gpr >= RETURN_REGNUM)))
    return;

  /* Search for prologue/epilogue insns and replace them.  */

  for (insn = get_insns (); insn; insn = next_insn)
    {
      int first, last, off;
      rtx set, base, offset;
      rtx pat;

      next_insn = NEXT_INSN (insn);

      if (! NONJUMP_INSN_P (insn) || ! RTX_FRAME_RELATED_P (insn))
        continue;

      pat = PATTERN (insn);

      /* Remove ldgr/lgdr instructions used for saving and restore
         GPRs if possible.  */
      if (TARGET_Z10
          && GET_CODE (pat) == SET
          && GET_MODE (SET_SRC (pat)) == DImode
          && REG_P (SET_SRC (pat))
          && REG_P (SET_DEST (pat)))
        {
          int src_regno = REGNO (SET_SRC (pat));
          int dest_regno = REGNO (SET_DEST (pat));
          int gpr_regno;
          int fpr_regno;

          if (!((GENERAL_REGNO_P (src_regno) && FP_REGNO_P (dest_regno))
                || (FP_REGNO_P (src_regno) && GENERAL_REGNO_P (dest_regno))))
            continue;

          gpr_regno = GENERAL_REGNO_P (src_regno) ? src_regno : dest_regno;
          fpr_regno = FP_REGNO_P (src_regno) ? src_regno : dest_regno;

          /* GPR must be call-saved, FPR must be call-clobbered.  */
          if (!call_really_used_regs[fpr_regno]
              || call_really_used_regs[gpr_regno])
            continue;

          /* It must not happen that what we once saved in an FPR now
             needs a stack slot.  */
          gcc_assert (cfun_gpr_save_slot (gpr_regno) != -1);

          if (cfun_gpr_save_slot (gpr_regno) == 0)
            {
              remove_insn (insn);
              continue;
            }
        }

      if (GET_CODE (pat) == PARALLEL
          && store_multiple_operation (pat, VOIDmode))
        {
          set = XVECEXP (pat, 0, 0);
          first = REGNO (SET_SRC (set));
          last = first + XVECLEN (pat, 0) - 1;
          offset = const0_rtx;
          base = eliminate_constant_term (XEXP (SET_DEST (set), 0), &offset);
          off = INTVAL (offset);

          if (GET_CODE (base) != REG || off < 0)
            continue;
          if (cfun_frame_layout.first_save_gpr != -1
              && (cfun_frame_layout.first_save_gpr < first
                  || cfun_frame_layout.last_save_gpr > last))
            continue;
          if (REGNO (base) != STACK_POINTER_REGNUM
              && REGNO (base) != HARD_FRAME_POINTER_REGNUM)
            continue;
          if (first > BASE_REGNUM || last < BASE_REGNUM)
            continue;

          if (cfun_frame_layout.first_save_gpr != -1)
            {
              rtx s_pat = save_gprs (base,
                                     off + (cfun_frame_layout.first_save_gpr
                                            - first) * UNITS_PER_LONG,
                                     cfun_frame_layout.first_save_gpr,
                                     cfun_frame_layout.last_save_gpr);
              new_insn = emit_insn_before (s_pat, insn);
              INSN_ADDRESSES_NEW (new_insn, -1);
            }

          remove_insn (insn);
          continue;
        }

      if (cfun_frame_layout.first_save_gpr == -1
          && GET_CODE (pat) == SET
          && GENERAL_REG_P (SET_SRC (pat))
          && GET_CODE (SET_DEST (pat)) == MEM)
        {
          set = pat;
          first = REGNO (SET_SRC (set));
          offset = const0_rtx;
          base = eliminate_constant_term (XEXP (SET_DEST (set), 0), &offset);
          off = INTVAL (offset);

          if (GET_CODE (base) != REG || off < 0)
            continue;
          if (REGNO (base) != STACK_POINTER_REGNUM
              && REGNO (base) != HARD_FRAME_POINTER_REGNUM)
            continue;

          remove_insn (insn);
          continue;
        }

      if (GET_CODE (pat) == PARALLEL
          && load_multiple_operation (pat, VOIDmode))
        {
          set = XVECEXP (pat, 0, 0);
          first = REGNO (SET_DEST (set));
          last = first + XVECLEN (pat, 0) - 1;
          offset = const0_rtx;
          base = eliminate_constant_term (XEXP (SET_SRC (set), 0), &offset);
          off = INTVAL (offset);

          if (GET_CODE (base) != REG || off < 0)
            continue;

          if (cfun_frame_layout.first_restore_gpr != -1
              && (cfun_frame_layout.first_restore_gpr < first
                  || cfun_frame_layout.last_restore_gpr > last))
            continue;
          if (REGNO (base) != STACK_POINTER_REGNUM
              && REGNO (base) != HARD_FRAME_POINTER_REGNUM)
            continue;
          if (first > BASE_REGNUM || last < BASE_REGNUM)
            continue;

          if (cfun_frame_layout.first_restore_gpr != -1)
            {
              rtx rpat = restore_gprs (base,
                                       off + (cfun_frame_layout.first_restore_gpr
                                              - first) * UNITS_PER_LONG,
                                       cfun_frame_layout.first_restore_gpr,
                                       cfun_frame_layout.last_restore_gpr);

              /* Remove REG_CFA_RESTOREs for registers that we no
                 longer need to save.  */
              REG_NOTES (rpat) = REG_NOTES (insn);
              for (rtx *ptr = &REG_NOTES (rpat); *ptr; )
                if (REG_NOTE_KIND (*ptr) == REG_CFA_RESTORE
                    && ((int) REGNO (XEXP (*ptr, 0))
                        < cfun_frame_layout.first_restore_gpr))
                  *ptr = XEXP (*ptr, 1);
                else
                  ptr = &XEXP (*ptr, 1);
              new_insn = emit_insn_before (rpat, insn);
              RTX_FRAME_RELATED_P (new_insn) = 1;
              INSN_ADDRESSES_NEW (new_insn, -1);
            }

          remove_insn (insn);
          continue;
        }

      if (cfun_frame_layout.first_restore_gpr == -1
          && GET_CODE (pat) == SET
          && GENERAL_REG_P (SET_DEST (pat))
          && GET_CODE (SET_SRC (pat)) == MEM)
        {
          set = pat;
          first = REGNO (SET_DEST (set));
          offset = const0_rtx;
          base = eliminate_constant_term (XEXP (SET_SRC (set), 0), &offset);
          off = INTVAL (offset);

          if (GET_CODE (base) != REG || off < 0)
            continue;

          if (REGNO (base) != STACK_POINTER_REGNUM
              && REGNO (base) != HARD_FRAME_POINTER_REGNUM)
            continue;

          remove_insn (insn);
          continue;
        }
    }
}

/* On z10 and later the dynamic branch prediction must see the
   backward jump within a certain windows.  If not it falls back to
   the static prediction.  This function rearranges the loop backward
   branch in a way which makes the static prediction always correct.
   The function returns true if it added an instruction.  */
static bool
s390_fix_long_loop_prediction (rtx_insn *insn)
{
  rtx set = single_set (insn);
  rtx code_label, label_ref, new_label;
  rtx_insn *uncond_jump;
  rtx_insn *cur_insn;
  rtx tmp;
  int distance;

  /* This will exclude branch on count and branch on index patterns
     since these are correctly statically predicted.  */
  if (!set
      || SET_DEST (set) != pc_rtx
      || GET_CODE (SET_SRC(set)) != IF_THEN_ELSE)
    return false;

  /* Skip conditional returns.  */
  if (ANY_RETURN_P (XEXP (SET_SRC (set), 1))
      && XEXP (SET_SRC (set), 2) == pc_rtx)
    return false;

  label_ref = (GET_CODE (XEXP (SET_SRC (set), 1)) == LABEL_REF ?
               XEXP (SET_SRC (set), 1) : XEXP (SET_SRC (set), 2));

  gcc_assert (GET_CODE (label_ref) == LABEL_REF);

  code_label = XEXP (label_ref, 0);

  if (INSN_ADDRESSES (INSN_UID (code_label)) == -1
      || INSN_ADDRESSES (INSN_UID (insn)) == -1
      || (INSN_ADDRESSES (INSN_UID (insn))
          - INSN_ADDRESSES (INSN_UID (code_label)) < PREDICT_DISTANCE))
    return false;

  for (distance = 0, cur_insn = PREV_INSN (insn);
       distance < PREDICT_DISTANCE - 6;
       distance += get_attr_length (cur_insn), cur_insn = PREV_INSN (cur_insn))
    if (!cur_insn || JUMP_P (cur_insn) || LABEL_P (cur_insn))
      return false;

  new_label = gen_label_rtx ();
  uncond_jump = emit_jump_insn_after (
                  gen_rtx_SET (VOIDmode, pc_rtx,
                               gen_rtx_LABEL_REF (VOIDmode, code_label)),
                  insn);
  emit_label_after (new_label, uncond_jump);

  tmp = XEXP (SET_SRC (set), 1);
  XEXP (SET_SRC (set), 1) = XEXP (SET_SRC (set), 2);
  XEXP (SET_SRC (set), 2) = tmp;
  INSN_CODE (insn) = -1;

  XEXP (label_ref, 0) = new_label;
  JUMP_LABEL (insn) = new_label;
  JUMP_LABEL (uncond_jump) = code_label;

  return true;
}

/* Returns 1 if INSN reads the value of REG for purposes not related
   to addressing of memory, and 0 otherwise.  */
static int
s390_non_addr_reg_read_p (rtx reg, rtx_insn *insn)
{
  return reg_referenced_p (reg, PATTERN (insn))
    && !reg_used_in_mem_p (REGNO (reg), PATTERN (insn));
}

/* Starting from INSN find_cond_jump looks downwards in the insn
   stream for a single jump insn which is the last user of the
   condition code set in INSN.  */
static rtx_insn *
find_cond_jump (rtx_insn *insn)
{
  for (; insn; insn = NEXT_INSN (insn))
    {
      rtx ite, cc;

      if (LABEL_P (insn))
        break;

      if (!JUMP_P (insn))
        {
          if (reg_mentioned_p (gen_rtx_REG (CCmode, CC_REGNUM), insn))
            break;
          continue;
        }

      /* This will be triggered by a return.  */
      if (GET_CODE (PATTERN (insn)) != SET)
        break;

      gcc_assert (SET_DEST (PATTERN (insn)) == pc_rtx);
      ite = SET_SRC (PATTERN (insn));

      if (GET_CODE (ite) != IF_THEN_ELSE)
        break;

      cc = XEXP (XEXP (ite, 0), 0);
      if (!REG_P (cc) || !CC_REGNO_P (REGNO (cc)))
        break;

      if (find_reg_note (insn, REG_DEAD, cc))
        return insn;
      break;
    }

  return NULL;
}

/* Swap the condition in COND and the operands in OP0 and OP1 so that
   the semantics does not change.  If NULL_RTX is passed as COND the
   function tries to find the conditional jump starting with INSN.  */
static void
s390_swap_cmp (rtx cond, rtx *op0, rtx *op1, rtx_insn *insn)
{
  rtx tmp = *op0;

  if (cond == NULL_RTX)
    {
      rtx_insn *jump = find_cond_jump (NEXT_INSN (insn));
      rtx set = jump ? single_set (jump) : NULL_RTX;

      if (set == NULL_RTX)
        return;

      cond = XEXP (SET_SRC (set), 0);
    }

  *op0 = *op1;
  *op1 = tmp;
  PUT_CODE (cond, swap_condition (GET_CODE (cond)));
}

/* On z10, instructions of the compare-and-branch family have the
   property to access the register occurring as second operand with
   its bits complemented.  If such a compare is grouped with a second
   instruction that accesses the same register non-complemented, and
   if that register's value is delivered via a bypass, then the
   pipeline recycles, thereby causing significant performance decline.
   This function locates such situations and exchanges the two
   operands of the compare.  The function return true whenever it
   added an insn.  */
static bool
s390_z10_optimize_cmp (rtx_insn *insn)
{
  rtx_insn *prev_insn, *next_insn;
  bool insn_added_p = false;
  rtx cond, *op0, *op1;

  if (GET_CODE (PATTERN (insn)) == PARALLEL)
    {
      /* Handle compare and branch and branch on count
         instructions.  */
      rtx pattern = single_set (insn);

      if (!pattern
          || SET_DEST (pattern) != pc_rtx
          || GET_CODE (SET_SRC (pattern)) != IF_THEN_ELSE)
        return false;

      cond = XEXP (SET_SRC (pattern), 0);
      op0 = &XEXP (cond, 0);
      op1 = &XEXP (cond, 1);
    }
  else if (GET_CODE (PATTERN (insn)) == SET)
    {
      rtx src, dest;

      /* Handle normal compare instructions.  */
      src = SET_SRC (PATTERN (insn));
      dest = SET_DEST (PATTERN (insn));

      if (!REG_P (dest)
          || !CC_REGNO_P (REGNO (dest))
          || GET_CODE (src) != COMPARE)
        return false;

      /* s390_swap_cmp will try to find the conditional
         jump when passing NULL_RTX as condition.  */
      cond = NULL_RTX;
      op0 = &XEXP (src, 0);
      op1 = &XEXP (src, 1);
    }
  else
    return false;

  if (!REG_P (*op0) || !REG_P (*op1))
    return false;

  if (GET_MODE_CLASS (GET_MODE (*op0)) != MODE_INT)
    return false;

  /* Swap the COMPARE arguments and its mask if there is a
     conflicting access in the previous insn.  */
  prev_insn = prev_active_insn (insn);
  if (prev_insn != NULL_RTX && INSN_P (prev_insn)
      && reg_referenced_p (*op1, PATTERN (prev_insn)))
    s390_swap_cmp (cond, op0, op1, insn);

  /* Check if there is a conflict with the next insn. If there
     was no conflict with the previous insn, then swap the
     COMPARE arguments and its mask.  If we already swapped
     the operands, or if swapping them would cause a conflict
     with the previous insn, issue a NOP after the COMPARE in
     order to separate the two instuctions.  */
  next_insn = next_active_insn (insn);
  if (next_insn != NULL_RTX && INSN_P (next_insn)
      && s390_non_addr_reg_read_p (*op1, next_insn))
    {
      if (prev_insn != NULL_RTX && INSN_P (prev_insn)
          && s390_non_addr_reg_read_p (*op0, prev_insn))
        {
          if (REGNO (*op1) == 0)
            emit_insn_after (gen_nop1 (), insn);
          else
            emit_insn_after (gen_nop (), insn);
          insn_added_p = true;
        }
      else
        s390_swap_cmp (cond, op0, op1, insn);
    }
  return insn_added_p;
}

/* Perform machine-dependent processing.  */

static void
s390_reorg (void)
{
  bool pool_overflow = false;

  /* Make sure all splits have been performed; splits after
     machine_dependent_reorg might confuse insn length counts.  */
  split_all_insns_noflow ();

  /* Install the main literal pool and the associated base
     register load insns.

     In addition, there are two problematic situations we need
     to correct:

     - the literal pool might be > 4096 bytes in size, so that
       some of its elements cannot be directly accessed

     - a branch target might be > 64K away from the branch, so that
       it is not possible to use a PC-relative instruction.

     To fix those, we split the single literal pool into multiple
     pool chunks, reloading the pool base register at various
     points throughout the function to ensure it always points to
     the pool chunk the following code expects, and / or replace
     PC-relative branches by absolute branches.

     However, the two problems are interdependent: splitting the
     literal pool can move a branch further away from its target,
     causing the 64K limit to overflow, and on the other hand,
     replacing a PC-relative branch by an absolute branch means
     we need to put the branch target address into the literal
     pool, possibly causing it to overflow.

     So, we loop trying to fix up both problems until we manage
     to satisfy both conditions at the same time.  Note that the
     loop is guaranteed to terminate as every pass of the loop
     strictly decreases the total number of PC-relative branches
     in the function.  (This is not completely true as there
     might be branch-over-pool insns introduced by chunkify_start.
     Those never need to be split however.)  */

  for (;;)
    {
      struct constant_pool *pool = NULL;

      /* Collect the literal pool.  */
      if (!pool_overflow)
        {
          pool = s390_mainpool_start ();
          if (!pool)
            pool_overflow = true;
        }

      /* If literal pool overflowed, start to chunkify it.  */
      if (pool_overflow)
        pool = s390_chunkify_start ();

      /* Split out-of-range branches.  If this has created new
         literal pool entries, cancel current chunk list and
         recompute it.  zSeries machines have large branch
         instructions, so we never need to split a branch.  */
      if (!TARGET_CPU_ZARCH && s390_split_branches ())
        {
          if (pool_overflow)
            s390_chunkify_cancel (pool);
          else
            s390_mainpool_cancel (pool);

          continue;
        }

      /* If we made it up to here, both conditions are satisfied.
         Finish up literal pool related changes.  */
      if (pool_overflow)
        s390_chunkify_finish (pool);
      else
        s390_mainpool_finish (pool);

      /* We're done splitting branches.  */
      cfun->machine->split_branches_pending_p = false;
      break;
    }

  /* Generate out-of-pool execute target insns.  */
  if (TARGET_CPU_ZARCH)
    {
      rtx_insn *insn, *target;
      rtx label;

      for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
        {
          label = s390_execute_label (insn);
          if (!label)
            continue;

          gcc_assert (label != const0_rtx);

          target = emit_label (XEXP (label, 0));
          INSN_ADDRESSES_NEW (target, -1);

          target = emit_insn (s390_execute_target (insn));
          INSN_ADDRESSES_NEW (target, -1);
        }
    }

  /* Try to optimize prologue and epilogue further.  */
  s390_optimize_prologue ();

  /* Walk over the insns and do some >=z10 specific changes.  */
  if (s390_tune == PROCESSOR_2097_Z10
      || s390_tune == PROCESSOR_2817_Z196
      || s390_tune == PROCESSOR_2827_ZEC12)
    {
      rtx_insn *insn;
      bool insn_added_p = false;

      /* The insn lengths and addresses have to be up to date for the
         following manipulations.  */
      shorten_branches (get_insns ());

      for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
        {
          if (!INSN_P (insn) || INSN_CODE (insn) <= 0)
            continue;

          if (JUMP_P (insn))
            insn_added_p |= s390_fix_long_loop_prediction (insn);

          if ((GET_CODE (PATTERN (insn)) == PARALLEL
               || GET_CODE (PATTERN (insn)) == SET)
              && s390_tune == PROCESSOR_2097_Z10)
            insn_added_p |= s390_z10_optimize_cmp (insn);
        }

      /* Adjust branches if we added new instructions.  */
      if (insn_added_p)
        shorten_branches (get_insns ());
    }
}

/* Return true if INSN is a fp load insn writing register REGNO.  */
static inline bool
s390_fpload_toreg (rtx_insn *insn, unsigned int regno)
{
  rtx set;
  enum attr_type flag = s390_safe_attr_type (insn);

  if (flag != TYPE_FLOADSF && flag != TYPE_FLOADDF)
    return false;

  set = single_set (insn);

  if (set == NULL_RTX)
    return false;

  if (!REG_P (SET_DEST (set)) || !MEM_P (SET_SRC (set)))
    return false;

  if (REGNO (SET_DEST (set)) != regno)
    return false;

  return true;
}

/* This value describes the distance to be avoided between an
   aritmetic fp instruction and an fp load writing the same register.
   Z10_EARLYLOAD_DISTANCE - 1 as well as Z10_EARLYLOAD_DISTANCE + 1 is
   fine but the exact value has to be avoided. Otherwise the FP
   pipeline will throw an exception causing a major penalty.  */
#define Z10_EARLYLOAD_DISTANCE 7

/* Rearrange the ready list in order to avoid the situation described
   for Z10_EARLYLOAD_DISTANCE.  A problematic load instruction is
   moved to the very end of the ready list.  */
static void
s390_z10_prevent_earlyload_conflicts (rtx_insn **ready, int *nready_p)
{
  unsigned int regno;
  int nready = *nready_p;
  rtx_insn *tmp;
  int i;
  rtx_insn *insn;
  rtx set;
  enum attr_type flag;
  int distance;

  /* Skip DISTANCE - 1 active insns.  */
  for (insn = last_scheduled_insn, distance = Z10_EARLYLOAD_DISTANCE - 1;
       distance > 0 && insn != NULL_RTX;
       distance--, insn = prev_active_insn (insn))
    if (CALL_P (insn) || JUMP_P (insn))
      return;

  if (insn == NULL_RTX)
    return;

  set = single_set (insn);

  if (set == NULL_RTX || !REG_P (SET_DEST (set))
      || GET_MODE_CLASS (GET_MODE (SET_DEST (set))) != MODE_FLOAT)
    return;

  flag = s390_safe_attr_type (insn);

  if (flag == TYPE_FLOADSF || flag == TYPE_FLOADDF)
    return;

  regno = REGNO (SET_DEST (set));
  i = nready - 1;

  while (!s390_fpload_toreg (ready[i], regno) && i > 0)
    i--;

  if (!i)
    return;

  tmp = ready[i];
  memmove (&ready[1], &ready[0], sizeof (rtx_insn *) * i);
  ready[0] = tmp;
}


/* The s390_sched_state variable tracks the state of the current or
   the last instruction group.

   0,1,2 number of instructions scheduled in the current group
   3     the last group is complete - normal insns
   4     the last group was a cracked/expanded insn */

static int s390_sched_state;

#define S390_OOO_SCHED_STATE_NORMAL  3
#define S390_OOO_SCHED_STATE_CRACKED 4

#define S390_OOO_SCHED_ATTR_MASK_CRACKED    0x1
#define S390_OOO_SCHED_ATTR_MASK_EXPANDED   0x2
#define S390_OOO_SCHED_ATTR_MASK_ENDGROUP   0x4
#define S390_OOO_SCHED_ATTR_MASK_GROUPALONE 0x8

static unsigned int
s390_get_sched_attrmask (rtx_insn *insn)
{
  unsigned int mask = 0;

  if (get_attr_ooo_cracked (insn))
    mask |= S390_OOO_SCHED_ATTR_MASK_CRACKED;
  if (get_attr_ooo_expanded (insn))
    mask |= S390_OOO_SCHED_ATTR_MASK_EXPANDED;
  if (get_attr_ooo_endgroup (insn))
    mask |= S390_OOO_SCHED_ATTR_MASK_ENDGROUP;
  if (get_attr_ooo_groupalone (insn))
    mask |= S390_OOO_SCHED_ATTR_MASK_GROUPALONE;
  return mask;
}

/* Return the scheduling score for INSN.  The higher the score the
   better.  The score is calculated from the OOO scheduling attributes
   of INSN and the scheduling state s390_sched_state.  */
static int
s390_sched_score (rtx_insn *insn)
{
  unsigned int mask = s390_get_sched_attrmask (insn);
  int score = 0;

  switch (s390_sched_state)
    {
    case 0:
      /* Try to put insns into the first slot which would otherwise
         break a group.  */
      if ((mask & S390_OOO_SCHED_ATTR_MASK_CRACKED) != 0
          || (mask & S390_OOO_SCHED_ATTR_MASK_EXPANDED) != 0)
        score += 5;
      if ((mask & S390_OOO_SCHED_ATTR_MASK_GROUPALONE) != 0)
        score += 10;
    case 1:
      /* Prefer not cracked insns while trying to put together a
         group.  */
      if ((mask & S390_OOO_SCHED_ATTR_MASK_CRACKED) == 0
          && (mask & S390_OOO_SCHED_ATTR_MASK_EXPANDED) == 0
          && (mask & S390_OOO_SCHED_ATTR_MASK_GROUPALONE) == 0)
        score += 10;
      if ((mask & S390_OOO_SCHED_ATTR_MASK_ENDGROUP) == 0)
        score += 5;
      break;
    case 2:
      /* Prefer not cracked insns while trying to put together a
         group.  */
      if ((mask & S390_OOO_SCHED_ATTR_MASK_CRACKED) == 0
          && (mask & S390_OOO_SCHED_ATTR_MASK_EXPANDED) == 0
          && (mask & S390_OOO_SCHED_ATTR_MASK_GROUPALONE) == 0)
        score += 10;
      /* Prefer endgroup insns in the last slot.  */
      if ((mask & S390_OOO_SCHED_ATTR_MASK_ENDGROUP) != 0)
        score += 10;
      break;
    case S390_OOO_SCHED_STATE_NORMAL:
      /* Prefer not cracked insns if the last was not cracked.  */
      if ((mask & S390_OOO_SCHED_ATTR_MASK_CRACKED) == 0
          && (mask & S390_OOO_SCHED_ATTR_MASK_EXPANDED) == 0)
        score += 5;
      if ((mask & S390_OOO_SCHED_ATTR_MASK_GROUPALONE) != 0)
        score += 10;
      break;
    case S390_OOO_SCHED_STATE_CRACKED:
      /* Try to keep cracked insns together to prevent them from
         interrupting groups.  */
      if ((mask & S390_OOO_SCHED_ATTR_MASK_CRACKED) != 0
          || (mask & S390_OOO_SCHED_ATTR_MASK_EXPANDED) != 0)
        score += 5;
      break;
    }
  return score;
}

/* This function is called via hook TARGET_SCHED_REORDER before
   issuing one insn from list READY which contains *NREADYP entries.
   For target z10 it reorders load instructions to avoid early load
   conflicts in the floating point pipeline  */
static int
s390_sched_reorder (FILE *file, int verbose,
                    rtx_insn **ready, int *nreadyp, int clock ATTRIBUTE_UNUSED)
{
  if (s390_tune == PROCESSOR_2097_Z10)
    if (reload_completed && *nreadyp > 1)
      s390_z10_prevent_earlyload_conflicts (ready, nreadyp);

  if (s390_tune == PROCESSOR_2827_ZEC12
      && reload_completed
      && *nreadyp > 1)
    {
      int i;
      int last_index = *nreadyp - 1;
      int max_index = -1;
      int max_score = -1;
      rtx_insn *tmp;

      /* Just move the insn with the highest score to the top (the
         end) of the list.  A full sort is not needed since a conflict
         in the hazard recognition cannot happen.  So the top insn in
         the ready list will always be taken.  */
      for (i = last_index; i >= 0; i--)
        {
          int score;

          if (recog_memoized (ready[i]) < 0)
            continue;

          score = s390_sched_score (ready[i]);
          if (score > max_score)
            {
              max_score = score;
              max_index = i;
            }
        }

      if (max_index != -1)
        {
          if (max_index != last_index)
            {
              tmp = ready[max_index];
              ready[max_index] = ready[last_index];
              ready[last_index] = tmp;

              if (verbose > 5)
                fprintf (file,
                         "move insn %d to the top of list\n",
                         INSN_UID (ready[last_index]));
            }
          else if (verbose > 5)
            fprintf (file,
                     "best insn %d already on top\n",
                     INSN_UID (ready[last_index]));
        }

      if (verbose > 5)
        {
          fprintf (file, "ready list ooo attributes - sched state: %d\n",
                   s390_sched_state);

          for (i = last_index; i >= 0; i--)
            {
              if (recog_memoized (ready[i]) < 0)
                continue;
              fprintf (file, "insn %d score: %d: ", INSN_UID (ready[i]),
                       s390_sched_score (ready[i]));
#define PRINT_OOO_ATTR(ATTR) fprintf (file, "%s ", get_attr_##ATTR (ready[i]) ? #ATTR : "!" #ATTR);
              PRINT_OOO_ATTR (ooo_cracked);
              PRINT_OOO_ATTR (ooo_expanded);
              PRINT_OOO_ATTR (ooo_endgroup);
              PRINT_OOO_ATTR (ooo_groupalone);
#undef PRINT_OOO_ATTR
              fprintf (file, "\n");
            }
        }
    }

  return s390_issue_rate ();
}


/* This function is called via hook TARGET_SCHED_VARIABLE_ISSUE after
   the scheduler has issued INSN.  It stores the last issued insn into
   last_scheduled_insn in order to make it available for
   s390_sched_reorder.  */
static int
s390_sched_variable_issue (FILE *file, int verbose, rtx_insn *insn, int more)
{
  last_scheduled_insn = insn;

  if (s390_tune == PROCESSOR_2827_ZEC12
      && reload_completed
      && recog_memoized (insn) >= 0)
    {
      unsigned int mask = s390_get_sched_attrmask (insn);

      if ((mask & S390_OOO_SCHED_ATTR_MASK_CRACKED) != 0
          || (mask & S390_OOO_SCHED_ATTR_MASK_EXPANDED) != 0)
        s390_sched_state = S390_OOO_SCHED_STATE_CRACKED;
      else if ((mask & S390_OOO_SCHED_ATTR_MASK_ENDGROUP) != 0
               || (mask & S390_OOO_SCHED_ATTR_MASK_GROUPALONE) != 0)
        s390_sched_state = S390_OOO_SCHED_STATE_NORMAL;
      else
        {
          /* Only normal insns are left (mask == 0).  */
          switch (s390_sched_state)
            {
            case 0:
            case 1:
            case 2:
            case S390_OOO_SCHED_STATE_NORMAL:
              if (s390_sched_state == S390_OOO_SCHED_STATE_NORMAL)
                s390_sched_state = 1;
              else
                s390_sched_state++;

              break;
            case S390_OOO_SCHED_STATE_CRACKED:
              s390_sched_state = S390_OOO_SCHED_STATE_NORMAL;
              break;
            }
        }
      if (verbose > 5)
        {
          fprintf (file, "insn %d: ", INSN_UID (insn));
#define PRINT_OOO_ATTR(ATTR)                                            \
          fprintf (file, "%s ", get_attr_##ATTR (insn) ? #ATTR : "");
          PRINT_OOO_ATTR (ooo_cracked);
          PRINT_OOO_ATTR (ooo_expanded);
          PRINT_OOO_ATTR (ooo_endgroup);
          PRINT_OOO_ATTR (ooo_groupalone);
#undef PRINT_OOO_ATTR
          fprintf (file, "\n");
          fprintf (file, "sched state: %d\n", s390_sched_state);
        }
    }

  if (GET_CODE (PATTERN (insn)) != USE
      && GET_CODE (PATTERN (insn)) != CLOBBER)
    return more - 1;
  else
    return more;
}

static void
s390_sched_init (FILE *file ATTRIBUTE_UNUSED,
                 int verbose ATTRIBUTE_UNUSED,
                 int max_ready ATTRIBUTE_UNUSED)
{
  last_scheduled_insn = NULL;
  s390_sched_state = 0;
}

/* This target hook implementation for TARGET_LOOP_UNROLL_ADJUST calculates
   a new number struct loop *loop should be unrolled if tuned for cpus with
   a built-in stride prefetcher.
   The loop is analyzed for memory accesses by calling check_dpu for
   each rtx of the loop. Depending on the loop_depth and the amount of
   memory accesses a new number <=nunroll is returned to improve the
   behaviour of the hardware prefetch unit.  */
static unsigned
s390_loop_unroll_adjust (unsigned nunroll, struct loop *loop)
{
  basic_block *bbs;
  rtx_insn *insn;
  unsigned i;
  unsigned mem_count = 0;

  if (s390_tune != PROCESSOR_2097_Z10
      && s390_tune != PROCESSOR_2817_Z196
      && s390_tune != PROCESSOR_2827_ZEC12)
    return nunroll;

  /* Count the number of memory references within the loop body.  */
  bbs = get_loop_body (loop);
  subrtx_iterator::array_type array;
  for (i = 0; i < loop->num_nodes; i++)
    FOR_BB_INSNS (bbs[i], insn)
      if (INSN_P (insn) && INSN_CODE (insn) != -1)
        FOR_EACH_SUBRTX (iter, array, PATTERN (insn), NONCONST)
          if (MEM_P (*iter))
            mem_count += 1;
  free (bbs);

  /* Prevent division by zero, and we do not need to adjust nunroll in this case.  */
  if (mem_count == 0)
    return nunroll;

  switch (loop_depth(loop))
    {
    case 1:
      return MIN (nunroll, 28 / mem_count);
    case 2:
      return MIN (nunroll, 22 / mem_count);
    default:
      return MIN (nunroll, 16 / mem_count);
    }
}

static void
s390_option_override (void)
{
  unsigned int i;
  cl_deferred_option *opt;
  vec<cl_deferred_option> *v =
    (vec<cl_deferred_option> *) s390_deferred_options;

  if (v)
    FOR_EACH_VEC_ELT (*v, i, opt)
      {
        switch (opt->opt_index)
          {
          case OPT_mhotpatch:
            s390_hotpatch_trampoline_halfwords = (opt->value) ?
              s390_hotpatch_trampoline_halfwords_default : -1;
            break;
          case OPT_mhotpatch_:
            {
              int val;

              val = integral_argument (opt->arg);
              if (val == -1)
                {
                  /* argument is not a plain number */
                  error ("argument to %qs should be a non-negative integer",
                         "-mhotpatch=");
                  break;
                }
              else if (val > s390_hotpatch_trampoline_halfwords_max)
                {
                  error ("argument to %qs is too large (max. %d)",
                         "-mhotpatch=", s390_hotpatch_trampoline_halfwords_max);
                  break;
                }
              s390_hotpatch_trampoline_halfwords = val;
              break;
            }
          default:
            gcc_unreachable ();
          }
      }

  /* Set up function hooks.  */
  init_machine_status = s390_init_machine_status;

  /* Architecture mode defaults according to ABI.  */
  if (!(target_flags_explicit & MASK_ZARCH))
    {
      if (TARGET_64BIT)
        target_flags |= MASK_ZARCH;
      else
        target_flags &= ~MASK_ZARCH;
    }

  /* Set the march default in case it hasn't been specified on
     cmdline.  */
  if (s390_arch == PROCESSOR_max)
    {
      s390_arch_string = TARGET_ZARCH? "z900" : "g5";
      s390_arch = TARGET_ZARCH ? PROCESSOR_2064_Z900 : PROCESSOR_9672_G5;
      s390_arch_flags = processor_flags_table[(int)s390_arch];
    }

  /* Determine processor to tune for.  */
  if (s390_tune == PROCESSOR_max)
    {
      s390_tune = s390_arch;
      s390_tune_flags = s390_arch_flags;
    }

  /* Sanity checks.  */
  if (TARGET_ZARCH && !TARGET_CPU_ZARCH)
    error ("z/Architecture mode not supported on %s", s390_arch_string);
  if (TARGET_64BIT && !TARGET_ZARCH)
    error ("64-bit ABI not supported in ESA/390 mode");

  /* Use hardware DFP if available and not explicitly disabled by
     user. E.g. with -m31 -march=z10 -mzarch   */
  if (!(target_flags_explicit & MASK_HARD_DFP) && TARGET_DFP)
    target_flags |= MASK_HARD_DFP;

  /* Enable hardware transactions if available and not explicitly
     disabled by user.  E.g. with -m31 -march=zEC12 -mzarch */
  if (!(target_flags_explicit & MASK_OPT_HTM) && TARGET_CPU_HTM && TARGET_ZARCH)
    target_flags |= MASK_OPT_HTM;

  if (TARGET_HARD_DFP && !TARGET_DFP)
    {
      if (target_flags_explicit & MASK_HARD_DFP)
        {
          if (!TARGET_CPU_DFP)
            error ("hardware decimal floating point instructions"
                   " not available on %s", s390_arch_string);
          if (!TARGET_ZARCH)
            error ("hardware decimal floating point instructions"
                   " not available in ESA/390 mode");
        }
      else
        target_flags &= ~MASK_HARD_DFP;
    }

  if ((target_flags_explicit & MASK_SOFT_FLOAT) && TARGET_SOFT_FLOAT)
    {
      if ((target_flags_explicit & MASK_HARD_DFP) && TARGET_HARD_DFP)
        error ("-mhard-dfp can%'t be used in conjunction with -msoft-float");

      target_flags &= ~MASK_HARD_DFP;
    }

  /* Set processor cost function.  */
  switch (s390_tune)
    {
    case PROCESSOR_2084_Z990:
      s390_cost = &z990_cost;
      break;
    case PROCESSOR_2094_Z9_109:
      s390_cost = &z9_109_cost;
      break;
    case PROCESSOR_2097_Z10:
      s390_cost = &z10_cost;
      break;
    case PROCESSOR_2817_Z196:
      s390_cost = &z196_cost;
      break;
    case PROCESSOR_2827_ZEC12:
      s390_cost = &zEC12_cost;
      break;
    default:
      s390_cost = &z900_cost;
    }

  if (TARGET_BACKCHAIN && TARGET_PACKED_STACK && TARGET_HARD_FLOAT)
    error ("-mbackchain -mpacked-stack -mhard-float are not supported "
           "in combination");

  if (s390_stack_size)
    {
      if (s390_stack_guard >= s390_stack_size)
        error ("stack size must be greater than the stack guard value");
      else if (s390_stack_size > 1 << 16)
        error ("stack size must not be greater than 64k");
    }
  else if (s390_stack_guard)
    error ("-mstack-guard implies use of -mstack-size");

#ifdef TARGET_DEFAULT_LONG_DOUBLE_128
  if (!(target_flags_explicit & MASK_LONG_DOUBLE_128))
    target_flags |= MASK_LONG_DOUBLE_128;
#endif

  if (s390_tune == PROCESSOR_2097_Z10
      || s390_tune == PROCESSOR_2817_Z196
      || s390_tune == PROCESSOR_2827_ZEC12)
    {
      maybe_set_param_value (PARAM_MAX_UNROLLED_INSNS, 100,
                             global_options.x_param_values,
                             global_options_set.x_param_values);
      maybe_set_param_value (PARAM_MAX_UNROLL_TIMES, 32,
                             global_options.x_param_values,
                             global_options_set.x_param_values);
      maybe_set_param_value (PARAM_MAX_COMPLETELY_PEELED_INSNS, 2000,
                             global_options.x_param_values,
                             global_options_set.x_param_values);
      maybe_set_param_value (PARAM_MAX_COMPLETELY_PEEL_TIMES, 64,
                             global_options.x_param_values,
                             global_options_set.x_param_values);
    }

  maybe_set_param_value (PARAM_MAX_PENDING_LIST_LENGTH, 256,
                         global_options.x_param_values,
                         global_options_set.x_param_values);
  /* values for loop prefetching */
  maybe_set_param_value (PARAM_L1_CACHE_LINE_SIZE, 256,
                         global_options.x_param_values,
                         global_options_set.x_param_values);
  maybe_set_param_value (PARAM_L1_CACHE_SIZE, 128,
                         global_options.x_param_values,
                         global_options_set.x_param_values);
  /* s390 has more than 2 levels and the size is much larger.  Since
     we are always running virtualized assume that we only get a small
     part of the caches above l1.  */
  maybe_set_param_value (PARAM_L2_CACHE_SIZE, 1500,
                         global_options.x_param_values,
                         global_options_set.x_param_values);
  maybe_set_param_value (PARAM_PREFETCH_MIN_INSN_TO_MEM_RATIO, 2,
                         global_options.x_param_values,
                         global_options_set.x_param_values);
  maybe_set_param_value (PARAM_SIMULTANEOUS_PREFETCHES, 6,
                         global_options.x_param_values,
                         global_options_set.x_param_values);

  /* This cannot reside in s390_option_optimization_table since HAVE_prefetch
     requires the arch flags to be evaluated already.  Since prefetching
     is beneficial on s390, we enable it if available.  */
  if (flag_prefetch_loop_arrays < 0 && HAVE_prefetch && optimize >= 3)
    flag_prefetch_loop_arrays = 1;

  /* Use the alternative scheduling-pressure algorithm by default.  */
  maybe_set_param_value (PARAM_SCHED_PRESSURE_ALGORITHM, 2,
                         global_options.x_param_values,
                         global_options_set.x_param_values);

  if (TARGET_TPF)
    {
      /* Don't emit DWARF3/4 unless specifically selected.  The TPF
         debuggers do not yet support DWARF 3/4.  */
      if (!global_options_set.x_dwarf_strict) 
        dwarf_strict = 1;
      if (!global_options_set.x_dwarf_version)
        dwarf_version = 2;
    }

  /* Register a target-specific optimization-and-lowering pass
     to run immediately before prologue and epilogue generation.

     Registering the pass must be done at start up.  It's
     convenient to do it here.  */
  opt_pass *new_pass = new pass_s390_early_mach (g);
  struct register_pass_info insert_pass_s390_early_mach =
    {
      new_pass,                 /* pass */
      "pro_and_epilogue",       /* reference_pass_name */
      1,                        /* ref_pass_instance_number */
      PASS_POS_INSERT_BEFORE    /* po_op */
    };
  register_pass (&insert_pass_s390_early_mach);
}

/* Implement TARGET_USE_BY_PIECES_INFRASTRUCTURE_P.  */

static bool
s390_use_by_pieces_infrastructure_p (unsigned HOST_WIDE_INT size,
                                     unsigned int align ATTRIBUTE_UNUSED,
                                     enum by_pieces_operation op ATTRIBUTE_UNUSED,
                                     bool speed_p ATTRIBUTE_UNUSED)
{
  return (size == 1 || size == 2
          || size == 4 || (TARGET_ZARCH && size == 8));
}

/* Initialize GCC target structure.  */

#undef  TARGET_ASM_ALIGNED_HI_OP
#define TARGET_ASM_ALIGNED_HI_OP "\t.word\t"
#undef  TARGET_ASM_ALIGNED_DI_OP
#define TARGET_ASM_ALIGNED_DI_OP "\t.quad\t"
#undef  TARGET_ASM_INTEGER
#define TARGET_ASM_INTEGER s390_assemble_integer

#undef  TARGET_ASM_OPEN_PAREN
#define TARGET_ASM_OPEN_PAREN ""

#undef  TARGET_ASM_CLOSE_PAREN
#define TARGET_ASM_CLOSE_PAREN ""

#undef TARGET_OPTION_OVERRIDE
#define TARGET_OPTION_OVERRIDE s390_option_override

#undef  TARGET_ENCODE_SECTION_INFO
#define TARGET_ENCODE_SECTION_INFO s390_encode_section_info

#undef TARGET_SCALAR_MODE_SUPPORTED_P
#define TARGET_SCALAR_MODE_SUPPORTED_P s390_scalar_mode_supported_p

#ifdef HAVE_AS_TLS
#undef TARGET_HAVE_TLS
#define TARGET_HAVE_TLS true
#endif
#undef TARGET_CANNOT_FORCE_CONST_MEM
#define TARGET_CANNOT_FORCE_CONST_MEM s390_cannot_force_const_mem

#undef TARGET_DELEGITIMIZE_ADDRESS
#define TARGET_DELEGITIMIZE_ADDRESS s390_delegitimize_address

#undef TARGET_LEGITIMIZE_ADDRESS
#define TARGET_LEGITIMIZE_ADDRESS s390_legitimize_address

#undef TARGET_RETURN_IN_MEMORY
#define TARGET_RETURN_IN_MEMORY s390_return_in_memory

#undef  TARGET_INIT_BUILTINS
#define TARGET_INIT_BUILTINS s390_init_builtins
#undef  TARGET_EXPAND_BUILTIN
#define TARGET_EXPAND_BUILTIN s390_expand_builtin

#undef TARGET_ASM_OUTPUT_ADDR_CONST_EXTRA
#define TARGET_ASM_OUTPUT_ADDR_CONST_EXTRA s390_output_addr_const_extra

#undef TARGET_ASM_OUTPUT_MI_THUNK
#define TARGET_ASM_OUTPUT_MI_THUNK s390_output_mi_thunk
#undef TARGET_ASM_CAN_OUTPUT_MI_THUNK
#define TARGET_ASM_CAN_OUTPUT_MI_THUNK hook_bool_const_tree_hwi_hwi_const_tree_true

#undef  TARGET_SCHED_ADJUST_PRIORITY
#define TARGET_SCHED_ADJUST_PRIORITY s390_adjust_priority
#undef TARGET_SCHED_ISSUE_RATE
#define TARGET_SCHED_ISSUE_RATE s390_issue_rate
#undef TARGET_SCHED_FIRST_CYCLE_MULTIPASS_DFA_LOOKAHEAD
#define TARGET_SCHED_FIRST_CYCLE_MULTIPASS_DFA_LOOKAHEAD s390_first_cycle_multipass_dfa_lookahead

#undef TARGET_SCHED_VARIABLE_ISSUE
#define TARGET_SCHED_VARIABLE_ISSUE s390_sched_variable_issue
#undef TARGET_SCHED_REORDER
#define TARGET_SCHED_REORDER s390_sched_reorder
#undef TARGET_SCHED_INIT
#define TARGET_SCHED_INIT s390_sched_init

#undef TARGET_CANNOT_COPY_INSN_P
#define TARGET_CANNOT_COPY_INSN_P s390_cannot_copy_insn_p
#undef TARGET_RTX_COSTS
#define TARGET_RTX_COSTS s390_rtx_costs
#undef TARGET_ADDRESS_COST
#define TARGET_ADDRESS_COST s390_address_cost
#undef TARGET_REGISTER_MOVE_COST
#define TARGET_REGISTER_MOVE_COST s390_register_move_cost
#undef TARGET_MEMORY_MOVE_COST
#define TARGET_MEMORY_MOVE_COST s390_memory_move_cost

#undef TARGET_MACHINE_DEPENDENT_REORG
#define TARGET_MACHINE_DEPENDENT_REORG s390_reorg

#undef TARGET_VALID_POINTER_MODE
#define TARGET_VALID_POINTER_MODE s390_valid_pointer_mode

#undef TARGET_BUILD_BUILTIN_VA_LIST
#define TARGET_BUILD_BUILTIN_VA_LIST s390_build_builtin_va_list
#undef TARGET_EXPAND_BUILTIN_VA_START
#define TARGET_EXPAND_BUILTIN_VA_START s390_va_start
#undef TARGET_GIMPLIFY_VA_ARG_EXPR
#define TARGET_GIMPLIFY_VA_ARG_EXPR s390_gimplify_va_arg

#undef TARGET_PROMOTE_FUNCTION_MODE
#define TARGET_PROMOTE_FUNCTION_MODE s390_promote_function_mode
#undef TARGET_PASS_BY_REFERENCE
#define TARGET_PASS_BY_REFERENCE s390_pass_by_reference

#undef TARGET_FUNCTION_OK_FOR_SIBCALL
#define TARGET_FUNCTION_OK_FOR_SIBCALL s390_function_ok_for_sibcall
#undef TARGET_FUNCTION_ARG
#define TARGET_FUNCTION_ARG s390_function_arg
#undef TARGET_FUNCTION_ARG_ADVANCE
#define TARGET_FUNCTION_ARG_ADVANCE s390_function_arg_advance
#undef TARGET_FUNCTION_VALUE
#define TARGET_FUNCTION_VALUE s390_function_value
#undef TARGET_LIBCALL_VALUE
#define TARGET_LIBCALL_VALUE s390_libcall_value

#undef TARGET_KEEP_LEAF_WHEN_PROFILED
#define TARGET_KEEP_LEAF_WHEN_PROFILED s390_keep_leaf_when_profiled

#undef TARGET_FIXED_CONDITION_CODE_REGS
#define TARGET_FIXED_CONDITION_CODE_REGS s390_fixed_condition_code_regs

#undef TARGET_CC_MODES_COMPATIBLE
#define TARGET_CC_MODES_COMPATIBLE s390_cc_modes_compatible

#undef TARGET_INVALID_WITHIN_DOLOOP
#define TARGET_INVALID_WITHIN_DOLOOP hook_constcharptr_const_rtx_insn_null

#ifdef HAVE_AS_TLS
#undef TARGET_ASM_OUTPUT_DWARF_DTPREL
#define TARGET_ASM_OUTPUT_DWARF_DTPREL s390_output_dwarf_dtprel
#endif

#ifdef TARGET_ALTERNATE_LONG_DOUBLE_MANGLING
#undef TARGET_MANGLE_TYPE
#define TARGET_MANGLE_TYPE s390_mangle_type
#endif

#undef TARGET_SCALAR_MODE_SUPPORTED_P
#define TARGET_SCALAR_MODE_SUPPORTED_P s390_scalar_mode_supported_p

#undef  TARGET_PREFERRED_RELOAD_CLASS
#define TARGET_PREFERRED_RELOAD_CLASS s390_preferred_reload_class

#undef TARGET_SECONDARY_RELOAD
#define TARGET_SECONDARY_RELOAD s390_secondary_reload

#undef TARGET_LIBGCC_CMP_RETURN_MODE
#define TARGET_LIBGCC_CMP_RETURN_MODE s390_libgcc_cmp_return_mode

#undef TARGET_LIBGCC_SHIFT_COUNT_MODE
#define TARGET_LIBGCC_SHIFT_COUNT_MODE s390_libgcc_shift_count_mode

#undef TARGET_LEGITIMATE_ADDRESS_P
#define TARGET_LEGITIMATE_ADDRESS_P s390_legitimate_address_p

#undef TARGET_LEGITIMATE_CONSTANT_P
#define TARGET_LEGITIMATE_CONSTANT_P s390_legitimate_constant_p

#undef TARGET_LRA_P
#define TARGET_LRA_P s390_lra_p

#undef TARGET_CAN_ELIMINATE
#define TARGET_CAN_ELIMINATE s390_can_eliminate

#undef TARGET_CONDITIONAL_REGISTER_USAGE
#define TARGET_CONDITIONAL_REGISTER_USAGE s390_conditional_register_usage

#undef TARGET_LOOP_UNROLL_ADJUST
#define TARGET_LOOP_UNROLL_ADJUST s390_loop_unroll_adjust

#undef TARGET_ASM_TRAMPOLINE_TEMPLATE
#define TARGET_ASM_TRAMPOLINE_TEMPLATE s390_asm_trampoline_template
#undef TARGET_TRAMPOLINE_INIT
#define TARGET_TRAMPOLINE_INIT s390_trampoline_init

#undef TARGET_UNWIND_WORD_MODE
#define TARGET_UNWIND_WORD_MODE s390_unwind_word_mode

#undef TARGET_CANONICALIZE_COMPARISON
#define TARGET_CANONICALIZE_COMPARISON s390_canonicalize_comparison

#undef TARGET_HARD_REGNO_SCRATCH_OK
#define TARGET_HARD_REGNO_SCRATCH_OK s390_hard_regno_scratch_ok

#undef TARGET_ATTRIBUTE_TABLE
#define TARGET_ATTRIBUTE_TABLE s390_attribute_table

#undef TARGET_CAN_INLINE_P
#define TARGET_CAN_INLINE_P s390_can_inline_p

#undef TARGET_SET_UP_BY_PROLOGUE
#define TARGET_SET_UP_BY_PROLOGUE s300_set_up_by_prologue

#undef TARGET_USE_BY_PIECES_INFRASTRUCTURE_P
#define TARGET_USE_BY_PIECES_INFRASTRUCTURE_P \
  s390_use_by_pieces_infrastructure_p

struct gcc_target targetm = TARGET_INITIALIZER;

#include "gt-s390.h"