1/* Data structure definitions for a generic GCC target.
2   Copyright (C) 2001-2015 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
59struct 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
69union cumulative_args_t { void *p; };
70
71#endif /* !ENABLE_CHECKING */
72
73/* Types used by the record_gcc_switches() target function.  */
74enum 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/* Types of memory operation understood by the "by_pieces" infrastructure.
84   Used by the TARGET_USE_BY_PIECES_INFRASTRUCTURE_P target hook.  */
85
86enum by_pieces_operation
87{
88  CLEAR_BY_PIECES,
89  MOVE_BY_PIECES,
90  SET_BY_PIECES,
91  STORE_BY_PIECES
92};
93
94typedef int (* print_switch_fn_type) (print_switch_type, const char *);
95
96/* An example implementation for ELF targets.  Defined in varasm.c  */
97extern int elf_record_gcc_switches (print_switch_type type, const char *);
98
99/* Some places still assume that all pointer or address modes are the
100   standard Pmode and ptr_mode.  These optimizations become invalid if
101   the target actually supports multiple different modes.  For now,
102   we disable such optimizations on such targets, using this function.  */
103extern bool target_default_pointer_address_modes_p (void);
104
105/* For hooks which use the MOVE_RATIO macro, this gives the legacy default
106   behaviour.  */
107extern unsigned int get_move_ratio (bool);
108
109struct stdarg_info;
110struct spec_info_def;
111struct hard_reg_set_container;
112struct cgraph_node;
113struct cgraph_simd_clone;
114
115/* The struct used by the secondary_reload target hook.  */
116struct secondary_reload_info
117{
118  /* icode is actually an enum insn_code, but we don't want to force every
119     file that includes target.h to include optabs.h .  */
120  int icode;
121  int extra_cost; /* Cost for using (a) scratch register(s) to be taken
122		     into account by copy_cost.  */
123  /* The next two members are for the use of the backward
124     compatibility hook.  */
125  struct secondary_reload_info *prev_sri;
126  int t_icode; /* Actually an enum insn_code - see above.  */
127};
128
129/* This is defined in sched-int.h .  */
130struct _dep;
131
132/* This is defined in ddg.h .  */
133struct ddg;
134
135/* This is defined in cfgloop.h .  */
136struct loop;
137
138/* This is defined in tree-ssa-alias.h.  */
139struct ao_ref;
140
141/* This is defined in tree-vectorizer.h.  */
142struct _stmt_vec_info;
143
144/* These are defined in tree-vect-stmts.c.  */
145extern tree stmt_vectype (struct _stmt_vec_info *);
146extern bool stmt_in_inner_loop_p (struct _stmt_vec_info *);
147
148/* Assembler instructions for creating various kinds of integer object.  */
149
150struct asm_int_op
151{
152  const char *hi;
153  const char *si;
154  const char *di;
155  const char *ti;
156};
157
158/* Types of costs for vectorizer cost model.  */
159enum vect_cost_for_stmt
160{
161  scalar_stmt,
162  scalar_load,
163  scalar_store,
164  vector_stmt,
165  vector_load,
166  unaligned_load,
167  unaligned_store,
168  vector_store,
169  vec_to_scalar,
170  scalar_to_vec,
171  cond_branch_not_taken,
172  cond_branch_taken,
173  vec_perm,
174  vec_promote_demote,
175  vec_construct
176};
177
178/* Separate locations for which the vectorizer cost model should
179   track costs.  */
180enum vect_cost_model_location {
181  vect_prologue = 0,
182  vect_body = 1,
183  vect_epilogue = 2
184};
185
186/* The target structure.  This holds all the backend hooks.  */
187#define DEFHOOKPOD(NAME, DOC, TYPE, INIT) TYPE NAME;
188#define DEFHOOK(NAME, DOC, TYPE, PARAMS, INIT) TYPE (* NAME) PARAMS;
189#define DEFHOOK_UNDOC DEFHOOK
190#define HOOKSTRUCT(FRAGMENT) FRAGMENT
191
192#include "target.def"
193
194extern struct gcc_target targetm;
195
196#ifdef GCC_TM_H
197
198#ifndef CUMULATIVE_ARGS_MAGIC
199#define CUMULATIVE_ARGS_MAGIC ((void *) &targetm.calls)
200#endif
201
202static inline CUMULATIVE_ARGS *
203get_cumulative_args (cumulative_args_t arg)
204{
205#ifdef ENABLE_CHECKING
206  gcc_assert (arg.magic == CUMULATIVE_ARGS_MAGIC);
207#endif /* ENABLE_CHECKING */
208  return (CUMULATIVE_ARGS *) arg.p;
209}
210
211static inline cumulative_args_t
212pack_cumulative_args (CUMULATIVE_ARGS *arg)
213{
214  cumulative_args_t ret;
215
216#ifdef ENABLE_CHECKING
217  ret.magic = CUMULATIVE_ARGS_MAGIC;
218#endif /* ENABLE_CHECKING */
219  ret.p = (void *) arg;
220  return ret;
221}
222#endif /* GCC_TM_H */
223
224#endif /* GCC_TARGET_H */
225