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