gcc/target.h

   1 /* Data structure definitions for a generic GCC target.
   2    Copyright (C) 2001-2013 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify it
   5    under the terms of the GNU General Public License as published by the
   6    Free Software Foundation; either version 3, or (at your option) any
   7    later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; see the file COPYING3.  If not see
  16    <http://www.gnu.org/licenses/>.
  17
  18    In other words, you are welcome to use, share and improve this program.
  19    You are forbidden to forbid anyone else to use, share and improve
  20    what you give them.   Help stamp out software-hoarding!  */
  21
  22
  23 /* This file contains a data structure that describes a GCC target.
  24    At present it is incomplete, but in future it should grow to
  25    contain most or all target machine and target O/S specific
  26    information.
  27
  28    This structure has its initializer declared in target-def.h in the
  29    form of large macro TARGET_INITIALIZER that expands to many smaller
  30    macros.
  31
  32    The smaller macros each initialize one component of the structure,
  33    and each has a default.  Each target should have a file that
  34    includes target.h and target-def.h, and overrides any inappropriate
  35    defaults by undefining the relevant macro and defining a suitable
  36    replacement.  That file should then contain the definition of
  37    "targetm" like so:
  38
  39    struct gcc_target targetm = TARGET_INITIALIZER;
  40
  41    Doing things this way allows us to bring together everything that
  42    defines a GCC target.  By supplying a default that is appropriate
  43    to most targets, we can easily add new items without needing to
  44    edit dozens of target configuration files.  It should also allow us
  45    to gradually reduce the amount of conditional compilation that is
  46    scattered throughout GCC.  */
  47
  48 #ifndef GCC_TARGET_H
  49 #define GCC_TARGET_H
  50
  51 #include "insn-modes.h"
  52 #include "insn-codes.h"
  53 #include "double-int.h"
  54
  55 #ifdef ENABLE_CHECKING
  56
  57 typedef struct { void *magic; void *p; } cumulative_args_t;
  58
  59 #else /* !ENABLE_CHECKING */
  60
  61 /* When using a GCC build compiler, we could use
  62    __attribute__((transparent_union)) to get cumulative_args_t function
  63    arguments passed like scalars where the ABI would mandate a less
  64    efficient way of argument passing otherwise.  However, that would come
  65    at the cost of less type-safe !ENABLE_CHECKING compilation.  */
  66
  67 typedef union { void *p; } cumulative_args_t;
  68
  69 #endif /* !ENABLE_CHECKING */
  70
  71 /* Types used by the record_gcc_switches() target function.  */
  72 typedef enum
  73 {
  74   SWITCH_TYPE_PASSED,           /* A switch passed on the command line.  */
  75   SWITCH_TYPE_ENABLED,          /* An option that is currently enabled.  */
  76   SWITCH_TYPE_DESCRIPTIVE,      /* Descriptive text, not a switch or option.  */
  77   SWITCH_TYPE_LINE_START,       /* Please emit any necessary text at the start of a line.  */
  78   SWITCH_TYPE_LINE_END          /* Please emit a line terminator.  */
  79 }
  80 print_switch_type;
  81
  82 typedef int (* print_switch_fn_type) (print_switch_type, const char *);
  83
  84 /* An example implementation for ELF targets.  Defined in varasm.c  */
  85 extern int elf_record_gcc_switches (print_switch_type type, const char *);
  86
  87 /* Some places still assume that all pointer or address modes are the
  88    standard Pmode and ptr_mode.  These optimizations become invalid if
  89    the target actually supports multiple different modes.  For now,
  90    we disable such optimizations on such targets, using this function.  */
  91 extern bool target_default_pointer_address_modes_p (void);
  92
  93 struct stdarg_info;
  94 struct spec_info_def;
  95 struct hard_reg_set_container;
  96 struct cgraph_node;
  97 struct cgraph_simd_clone;
  98
  99 /* The struct used by the secondary_reload target hook.  */
 100 typedef struct secondary_reload_info
 101 {
 102   /* icode is actually an enum insn_code, but we don't want to force every
 103      file that includes target.h to include optabs.h .  */
 104   int icode;
 105   int extra_cost; /* Cost for using (a) scratch register(s) to be taken
 106                      into account by copy_cost.  */
 107   /* The next two members are for the use of the backward
 108      compatibility hook.  */
 109   struct secondary_reload_info *prev_sri;
 110   int t_icode; /* Actually an enum insn_code - see above.  */
 111 } secondary_reload_info;
 112
 113 /* This is defined in sched-int.h .  */
 114 struct _dep;
 115
 116 /* This is defined in ddg.h .  */
 117 struct ddg;
 118
 119 /* This is defined in cfgloop.h .  */
 120 struct loop;
 121
 122 /* This is defined in tree-ssa-alias.h.  */
 123 struct ao_ref_s;
 124
 125 /* This is defined in tree-vectorizer.h.  */
 126 struct _stmt_vec_info;
 127
 128 /* These are defined in tree-vect-stmts.c.  */
 129 extern tree stmt_vectype (struct _stmt_vec_info *);
 130 extern bool stmt_in_inner_loop_p (struct _stmt_vec_info *);
 131
 132 /* Assembler instructions for creating various kinds of integer object.  */
 133
 134 struct asm_int_op
 135 {
 136   const char *hi;
 137   const char *si;
 138   const char *di;
 139   const char *ti;
 140 };
 141
 142 /* Types of costs for vectorizer cost model.  */
 143 enum vect_cost_for_stmt
 144 {
 145   scalar_stmt,
 146   scalar_load,
 147   scalar_store,
 148   vector_stmt,
 149   vector_load,
 150   unaligned_load,
 151   unaligned_store,
 152   vector_store,
 153   vec_to_scalar,
 154   scalar_to_vec,
 155   cond_branch_not_taken,
 156   cond_branch_taken,
 157   vec_perm,
 158   vec_promote_demote,
 159   vec_construct
 160 };
 161
 162 /* Separate locations for which the vectorizer cost model should
 163    track costs.  */
 164 enum vect_cost_model_location {
 165   vect_prologue = 0,
 166   vect_body = 1,
 167   vect_epilogue = 2
 168 };
 169
 170 /* The target structure.  This holds all the backend hooks.  */
 171 #define DEFHOOKPOD(NAME, DOC, TYPE, INIT) TYPE NAME;
 172 #define DEFHOOK(NAME, DOC, TYPE, PARAMS, INIT) TYPE (* NAME) PARAMS;
 173 #define DEFHOOK_UNDOC DEFHOOK
 174 #define HOOKSTRUCT(FRAGMENT) FRAGMENT
 175
 176 #include "target.def"
 177
 178 extern struct gcc_target targetm;
 179
 180 #ifdef GCC_TM_H
 181
 182 #ifndef CUMULATIVE_ARGS_MAGIC
 183 #define CUMULATIVE_ARGS_MAGIC ((void *) &targetm.calls)
 184 #endif
 185
 186 static inline CUMULATIVE_ARGS *
 187 get_cumulative_args (cumulative_args_t arg)
 188 {
 189 #ifdef ENABLE_CHECKING
 190   gcc_assert (arg.magic == CUMULATIVE_ARGS_MAGIC);
 191 #endif /* ENABLE_CHECKING */
 192   return (CUMULATIVE_ARGS *) arg.p;
 193 }
 194
 195 static inline cumulative_args_t
 196 pack_cumulative_args (CUMULATIVE_ARGS *arg)
 197 {
 198   cumulative_args_t ret;
 199
 200 #ifdef ENABLE_CHECKING
 201   ret.magic = CUMULATIVE_ARGS_MAGIC;
 202 #endif /* ENABLE_CHECKING */
 203   ret.p = (void *) arg;
 204   return ret;
 205 }
 206 #endif /* GCC_TM_H */
 207
 208 #endif /* GCC_TARGET_H */