gcc/target.h

   1 /* Data structure definitions for a generic GCC target.
   2    Copyright (C) 2001-2014 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 "wide-int.h"
  54 #include "tm.h"
  55 #include "hard-reg-set.h"
  56
  57 #ifdef ENABLE_CHECKING
  58
  59 struct cumulative_args_t { void *magic; void *p; };
  60
  61 #else /* !ENABLE_CHECKING */
  62
  63 /* When using a GCC build compiler, we could use
  64    __attribute__((transparent_union)) to get cumulative_args_t function
  65    arguments passed like scalars where the ABI would mandate a less
  66    efficient way of argument passing otherwise.  However, that would come
  67    at the cost of less type-safe !ENABLE_CHECKING compilation.  */
  68
  69 union cumulative_args_t { void *p; };
  70
  71 #endif /* !ENABLE_CHECKING */
  72
  73 /* Types used by the record_gcc_switches() target function.  */
  74 enum print_switch_type
  75 {
  76   SWITCH_TYPE_PASSED,           /* A switch passed on the command line.  */
  77   SWITCH_TYPE_ENABLED,          /* An option that is currently enabled.  */
  78   SWITCH_TYPE_DESCRIPTIVE,      /* Descriptive text, not a switch or option.  */
  79   SWITCH_TYPE_LINE_START,       /* Please emit any necessary text at the start of a line.  */
  80   SWITCH_TYPE_LINE_END          /* Please emit a line terminator.  */
  81 };
  82
  83 typedef int (* print_switch_fn_type) (print_switch_type, const char *);
  84
  85 /* An example implementation for ELF targets.  Defined in varasm.c  */
  86 extern int elf_record_gcc_switches (print_switch_type type, const char *);
  87
  88 /* Some places still assume that all pointer or address modes are the
  89    standard Pmode and ptr_mode.  These optimizations become invalid if
  90    the target actually supports multiple different modes.  For now,
  91    we disable such optimizations on such targets, using this function.  */
  92 extern bool target_default_pointer_address_modes_p (void);
  93
  94 struct stdarg_info;
  95 struct spec_info_def;
  96 struct hard_reg_set_container;
  97 struct cgraph_node;
  98 struct cgraph_simd_clone;
  99
 100 /* The struct used by the secondary_reload target hook.  */
 101 struct secondary_reload_info
 102 {
 103   /* icode is actually an enum insn_code, but we don't want to force every
 104      file that includes target.h to include optabs.h .  */
 105   int icode;
 106   int extra_cost; /* Cost for using (a) scratch register(s) to be taken
 107                      into account by copy_cost.  */
 108   /* The next two members are for the use of the backward
 109      compatibility hook.  */
 110   struct secondary_reload_info *prev_sri;
 111   int t_icode; /* Actually an enum insn_code - see above.  */
 112 };
 113
 114 /* This is defined in sched-int.h .  */
 115 struct _dep;
 116
 117 /* This is defined in ddg.h .  */
 118 struct ddg;
 119
 120 /* This is defined in cfgloop.h .  */
 121 struct loop;
 122
 123 /* This is defined in tree-ssa-alias.h.  */
 124 struct ao_ref;
 125
 126 /* This is defined in tree-vectorizer.h.  */
 127 struct _stmt_vec_info;
 128
 129 /* These are defined in tree-vect-stmts.c.  */
 130 extern tree stmt_vectype (struct _stmt_vec_info *);
 131 extern bool stmt_in_inner_loop_p (struct _stmt_vec_info *);
 132
 133 /* Assembler instructions for creating various kinds of integer object.  */
 134
 135 struct asm_int_op
 136 {
 137   const char *hi;
 138   const char *si;
 139   const char *di;
 140   const char *ti;
 141 };
 142
 143 /* Types of costs for vectorizer cost model.  */
 144 enum vect_cost_for_stmt
 145 {
 146   scalar_stmt,
 147   scalar_load,
 148   scalar_store,
 149   vector_stmt,
 150   vector_load,
 151   unaligned_load,
 152   unaligned_store,
 153   vector_store,
 154   vec_to_scalar,
 155   scalar_to_vec,
 156   cond_branch_not_taken,
 157   cond_branch_taken,
 158   vec_perm,
 159   vec_promote_demote,
 160   vec_construct
 161 };
 162
 163 /* Separate locations for which the vectorizer cost model should
 164    track costs.  */
 165 enum vect_cost_model_location {
 166   vect_prologue = 0,
 167   vect_body = 1,
 168   vect_epilogue = 2
 169 };
 170
 171 /* The target structure.  This holds all the backend hooks.  */
 172 #define DEFHOOKPOD(NAME, DOC, TYPE, INIT) TYPE NAME;
 173 #define DEFHOOK(NAME, DOC, TYPE, PARAMS, INIT) TYPE (* NAME) PARAMS;
 174 #define DEFHOOK_UNDOC DEFHOOK
 175 #define HOOKSTRUCT(FRAGMENT) FRAGMENT
 176
 177 #include "target.def"
 178
 179 extern struct gcc_target targetm;
 180
 181 #ifdef GCC_TM_H
 182
 183 #ifndef CUMULATIVE_ARGS_MAGIC
 184 #define CUMULATIVE_ARGS_MAGIC ((void *) &targetm.calls)
 185 #endif
 186
 187 static inline CUMULATIVE_ARGS *
 188 get_cumulative_args (cumulative_args_t arg)
 189 {
 190 #ifdef ENABLE_CHECKING
 191   gcc_assert (arg.magic == CUMULATIVE_ARGS_MAGIC);
 192 #endif /* ENABLE_CHECKING */
 193   return (CUMULATIVE_ARGS *) arg.p;
 194 }
 195
 196 static inline cumulative_args_t
 197 pack_cumulative_args (CUMULATIVE_ARGS *arg)
 198 {
 199   cumulative_args_t ret;
 200
 201 #ifdef ENABLE_CHECKING
 202   ret.magic = CUMULATIVE_ARGS_MAGIC;
 203 #endif /* ENABLE_CHECKING */
 204   ret.p = (void *) arg;
 205   return ret;
 206 }
 207 #endif /* GCC_TM_H */
 208
 209 #endif /* GCC_TARGET_H */