1 /* Data structure definitions for a generic GCC target.
2 Copyright (C) 2001-2020 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-codes.h"
52 #include "tm.h"
53 #include "hard-reg-set.h"
54
55 #if CHECKING_P
56
57 struct cumulative_args_t { void *magic; void *p; };
58
59 #else /* !CHECKING_P */
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 !CHECKING_P compilation. */
66
67 union cumulative_args_t { void *p; };
68
69 #endif /* !CHECKING_P */
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 /* Types of memory operation understood by the "by_pieces" infrastructure.
82 Used by the TARGET_USE_BY_PIECES_INFRASTRUCTURE_P target hook and
83 internally by the functions in expr.c. */
84
85 enum by_pieces_operation
86 {
87 CLEAR_BY_PIECES,
88 MOVE_BY_PIECES,
89 SET_BY_PIECES,
90 STORE_BY_PIECES,
91 COMPARE_BY_PIECES
92 };
93
94 extern unsigned HOST_WIDE_INT by_pieces_ninsns (unsigned HOST_WIDE_INT,
95 unsigned int,
96 unsigned int,
97 by_pieces_operation);
98
99 typedef int (* print_switch_fn_type) (print_switch_type, const char *);
100
101 /* An example implementation for ELF targets. Defined in varasm.c */
102 extern int elf_record_gcc_switches (print_switch_type type, const char *);
103
104 /* Some places still assume that all pointer or address modes are the
105 standard Pmode and ptr_mode. These optimizations become invalid if
106 the target actually supports multiple different modes. For now,
107 we disable such optimizations on such targets, using this function. */
108 extern bool target_default_pointer_address_modes_p (void);
109
110 /* For hooks which use the MOVE_RATIO macro, this gives the legacy default
111 behavior. */
112 extern unsigned int get_move_ratio (bool);
113
114 struct stdarg_info;
115 struct spec_info_def;
116 struct hard_reg_set_container;
117 struct cgraph_node;
118 struct cgraph_simd_clone;
119
120 /* The struct used by the secondary_reload target hook. */
121 struct secondary_reload_info
122 {
123 /* icode is actually an enum insn_code, but we don't want to force every
124 file that includes target.h to include optabs.h . */
125 int icode;
126 int extra_cost; /* Cost for using (a) scratch register(s) to be taken
127 into account by copy_cost. */
128 /* The next two members are for the use of the backward
129 compatibility hook. */
130 struct secondary_reload_info *prev_sri;
131 int t_icode; /* Actually an enum insn_code - see above. */
132 };
133
134 /* This is defined in sched-int.h . */
135 struct _dep;
136
137 /* This is defined in ddg.h . */
138 struct ddg;
139
140 /* This is defined in cfgloop.h . */
141 class loop;
142
143 /* This is defined in ifcvt.h. */
144 struct noce_if_info;
145
146 /* This is defined in tree-ssa-alias.h. */
147 class ao_ref;
148
149 /* This is defined in tree-vectorizer.h. */
150 class _stmt_vec_info;
151
152 /* This is defined in calls.h. */
153 class function_arg_info;
154
155 /* This is defined in function-abi.h. */
156 class predefined_function_abi;
157
158 /* These are defined in tree-vect-stmts.c. */
159 extern tree stmt_vectype (class _stmt_vec_info *);
160 extern bool stmt_in_inner_loop_p (class _stmt_vec_info *);
161
162 /* Assembler instructions for creating various kinds of integer object. */
163
164 struct asm_int_op
165 {
166 const char *hi;
167 const char *psi;
168 const char *si;
169 const char *pdi;
170 const char *di;
171 const char *pti;
172 const char *ti;
173 };
174
175 /* Types of costs for vectorizer cost model. */
176 enum vect_cost_for_stmt
177 {
178 scalar_stmt,
179 scalar_load,
180 scalar_store,
181 vector_stmt,
182 vector_load,
183 vector_gather_load,
184 unaligned_load,
185 unaligned_store,
186 vector_store,
187 vector_scatter_store,
188 vec_to_scalar,
189 scalar_to_vec,
190 cond_branch_not_taken,
191 cond_branch_taken,
192 vec_perm,
193 vec_promote_demote,
194 vec_construct
195 };
196
197 /* Separate locations for which the vectorizer cost model should
198 track costs. */
199 enum vect_cost_model_location {
200 vect_prologue = 0,
201 vect_body = 1,
202 vect_epilogue = 2
203 };
204
205 class vec_perm_indices;
206
207 /* The type to use for lists of vector sizes. */
208 typedef vec<machine_mode> vector_modes;
209
210 /* Same, but can be used to construct local lists that are
211 automatically freed. */
212 typedef auto_vec<machine_mode, 8> auto_vector_modes;
213
214 /* First argument of targetm.omp.device_kind_arch_isa. */
215 enum omp_device_kind_arch_isa {
216 omp_device_kind,
217 omp_device_arch,
218 omp_device_isa
219 };
220
221 /* Flags returned by TARGET_VECTORIZE_AUTOVECTORIZE_VECTOR_MODES:
222
223 VECT_COMPARE_COSTS
224 Tells the loop vectorizer to try all the provided modes and
225 pick the one with the lowest cost. By default the vectorizer
226 will choose the first mode that works. */
227 const unsigned int VECT_COMPARE_COSTS = 1U << 0;
228
229 /* The contexts in which the use of a type T can be checked by
230 TARGET_VERIFY_TYPE_CONTEXT. */
231 enum type_context_kind {
232 /* Directly measuring the size of T. */
233 TCTX_SIZEOF,
234
235 /* Directly measuring the alignment of T. */
236 TCTX_ALIGNOF,
237
238 /* Creating objects of type T with static storage duration. */
239 TCTX_STATIC_STORAGE,
240
241 /* Creating objects of type T with thread-local storage duration. */
242 TCTX_THREAD_STORAGE,
243
244 /* Creating a field of type T. */
245 TCTX_FIELD,
246
247 /* Creating an array with elements of type T. */
248 TCTX_ARRAY_ELEMENT,
249
250 /* Adding to or subtracting from a pointer to T, or computing the
251 difference between two pointers when one of them is a pointer to T. */
252 TCTX_POINTER_ARITH,
253
254 /* Dynamically allocating objects of type T. */
255 TCTX_ALLOCATION,
256
257 /* Dynamically deallocating objects of type T. */
258 TCTX_DEALLOCATION,
259
260 /* Throwing or catching an object of type T. */
261 TCTX_EXCEPTIONS,
262
263 /* Capturing objects of type T by value in a closure. */
264 TCTX_CAPTURE_BY_COPY
265 };
266
267 extern bool verify_type_context (location_t, type_context_kind, const_tree,
268 bool = false);
269
270 /* The target structure. This holds all the backend hooks. */
271 #define DEFHOOKPOD(NAME, DOC, TYPE, INIT) TYPE NAME;
272 #define DEFHOOK(NAME, DOC, TYPE, PARAMS, INIT) TYPE (* NAME) PARAMS;
273 #define DEFHOOK_UNDOC DEFHOOK
274 #define HOOKSTRUCT(FRAGMENT) FRAGMENT
275
276 #include "target.def"
277
278 extern struct gcc_target targetm;
279
280 /* Return an estimate of the runtime value of X, for use in things
281 like cost calculations or profiling frequencies. Note that this
282 function should never be used in situations where the actual
283 runtime value is needed for correctness, since the function only
284 provides a rough guess. */
285
286 static inline HOST_WIDE_INT
estimated_poly_value(poly_int64 x)287 estimated_poly_value (poly_int64 x)
288 {
289 if (NUM_POLY_INT_COEFFS == 1)
290 return x.coeffs[0];
291 else
292 return targetm.estimated_poly_value (x);
293 }
294
295 #ifdef GCC_TM_H
296
297 #ifndef CUMULATIVE_ARGS_MAGIC
298 #define CUMULATIVE_ARGS_MAGIC ((void *) &targetm.calls)
299 #endif
300
301 static inline CUMULATIVE_ARGS *
get_cumulative_args(cumulative_args_t arg)302 get_cumulative_args (cumulative_args_t arg)
303 {
304 #if CHECKING_P
305 gcc_assert (arg.magic == CUMULATIVE_ARGS_MAGIC);
306 #endif /* CHECKING_P */
307 return (CUMULATIVE_ARGS *) arg.p;
308 }
309
310 static inline cumulative_args_t
pack_cumulative_args(CUMULATIVE_ARGS * arg)311 pack_cumulative_args (CUMULATIVE_ARGS *arg)
312 {
313 cumulative_args_t ret;
314
315 #if CHECKING_P
316 ret.magic = CUMULATIVE_ARGS_MAGIC;
317 #endif /* CHECKING_P */
318 ret.p = (void *) arg;
319 return ret;
320 }
321 #endif /* GCC_TM_H */
322
323 #endif /* GCC_TARGET_H */
324