Daily bump.
[official-gcc.git] / gcc / gimple-expr.c
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1 /* Gimple decl, type, and expression support functions.
3 Copyright (C) 2007-2021 Free Software Foundation, Inc.
4 Contributed by Aldy Hernandez <aldyh@redhat.com>
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "backend.h"
26 #include "tree.h"
27 #include "gimple.h"
28 #include "stringpool.h"
29 #include "gimple-ssa.h"
30 #include "fold-const.h"
31 #include "tree-eh.h"
32 #include "gimplify.h"
33 #include "stor-layout.h"
34 #include "demangle.h"
35 #include "hash-set.h"
36 #include "rtl.h"
37 #include "tree-pass.h"
38 #include "stringpool.h"
39 #include "attribs.h"
40 #include "target.h"
42 /* ----- Type related ----- */
44 /* Return true if the conversion from INNER_TYPE to OUTER_TYPE is a
45 useless type conversion, otherwise return false.
47 This function implicitly defines the middle-end type system. With
48 the notion of 'a < b' meaning that useless_type_conversion_p (a, b)
49 holds and 'a > b' meaning that useless_type_conversion_p (b, a) holds,
50 the following invariants shall be fulfilled:
52 1) useless_type_conversion_p is transitive.
53 If a < b and b < c then a < c.
55 2) useless_type_conversion_p is not symmetric.
56 From a < b does not follow a > b.
58 3) Types define the available set of operations applicable to values.
59 A type conversion is useless if the operations for the target type
60 is a subset of the operations for the source type. For example
61 casts to void* are useless, casts from void* are not (void* can't
62 be dereferenced or offsetted, but copied, hence its set of operations
63 is a strict subset of that of all other data pointer types). Casts
64 to const T* are useless (can't be written to), casts from const T*
65 to T* are not. */
67 bool
68 useless_type_conversion_p (tree outer_type, tree inner_type)
70 /* Do the following before stripping toplevel qualifiers. */
71 if (POINTER_TYPE_P (inner_type)
72 && POINTER_TYPE_P (outer_type))
74 /* Do not lose casts between pointers to different address spaces. */
75 if (TYPE_ADDR_SPACE (TREE_TYPE (outer_type))
76 != TYPE_ADDR_SPACE (TREE_TYPE (inner_type)))
77 return false;
78 /* Do not lose casts to function pointer types. */
79 if ((TREE_CODE (TREE_TYPE (outer_type)) == FUNCTION_TYPE
80 || TREE_CODE (TREE_TYPE (outer_type)) == METHOD_TYPE)
81 && !(TREE_CODE (TREE_TYPE (inner_type)) == FUNCTION_TYPE
82 || TREE_CODE (TREE_TYPE (inner_type)) == METHOD_TYPE))
83 return false;
86 /* From now on qualifiers on value types do not matter. */
87 inner_type = TYPE_MAIN_VARIANT (inner_type);
88 outer_type = TYPE_MAIN_VARIANT (outer_type);
90 if (inner_type == outer_type)
91 return true;
93 /* Changes in machine mode are never useless conversions because the RTL
94 middle-end expects explicit conversions between modes. */
95 if (TYPE_MODE (inner_type) != TYPE_MODE (outer_type))
96 return false;
98 /* If both the inner and outer types are integral types, then the
99 conversion is not necessary if they have the same mode and
100 signedness and precision, and both or neither are boolean. */
101 if (INTEGRAL_TYPE_P (inner_type)
102 && INTEGRAL_TYPE_P (outer_type))
104 /* Preserve changes in signedness or precision. */
105 if (TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type)
106 || TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
107 return false;
109 /* Preserve conversions to/from BOOLEAN_TYPE if types are not
110 of precision one. */
111 if (((TREE_CODE (inner_type) == BOOLEAN_TYPE)
112 != (TREE_CODE (outer_type) == BOOLEAN_TYPE))
113 && TYPE_PRECISION (outer_type) != 1)
114 return false;
116 /* We don't need to preserve changes in the types minimum or
117 maximum value in general as these do not generate code
118 unless the types precisions are different. */
119 return true;
122 /* Scalar floating point types with the same mode are compatible. */
123 else if (SCALAR_FLOAT_TYPE_P (inner_type)
124 && SCALAR_FLOAT_TYPE_P (outer_type))
125 return true;
127 /* Fixed point types with the same mode are compatible. */
128 else if (FIXED_POINT_TYPE_P (inner_type)
129 && FIXED_POINT_TYPE_P (outer_type))
130 return TYPE_SATURATING (inner_type) == TYPE_SATURATING (outer_type);
132 /* We need to take special care recursing to pointed-to types. */
133 else if (POINTER_TYPE_P (inner_type)
134 && POINTER_TYPE_P (outer_type))
136 /* We do not care for const qualification of the pointed-to types
137 as const qualification has no semantic value to the middle-end. */
139 /* Otherwise pointers/references are equivalent. */
140 return true;
143 /* Recurse for complex types. */
144 else if (TREE_CODE (inner_type) == COMPLEX_TYPE
145 && TREE_CODE (outer_type) == COMPLEX_TYPE)
146 return useless_type_conversion_p (TREE_TYPE (outer_type),
147 TREE_TYPE (inner_type));
149 /* Recurse for vector types with the same number of subparts. */
150 else if (TREE_CODE (inner_type) == VECTOR_TYPE
151 && TREE_CODE (outer_type) == VECTOR_TYPE)
152 return (known_eq (TYPE_VECTOR_SUBPARTS (inner_type),
153 TYPE_VECTOR_SUBPARTS (outer_type))
154 && useless_type_conversion_p (TREE_TYPE (outer_type),
155 TREE_TYPE (inner_type))
156 && targetm.compatible_vector_types_p (inner_type, outer_type));
158 else if (TREE_CODE (inner_type) == ARRAY_TYPE
159 && TREE_CODE (outer_type) == ARRAY_TYPE)
161 /* Preserve various attributes. */
162 if (TYPE_REVERSE_STORAGE_ORDER (inner_type)
163 != TYPE_REVERSE_STORAGE_ORDER (outer_type))
164 return false;
165 if (TYPE_STRING_FLAG (inner_type) != TYPE_STRING_FLAG (outer_type))
166 return false;
168 /* Conversions from array types with unknown extent to
169 array types with known extent are not useless. */
170 if (!TYPE_DOMAIN (inner_type) && TYPE_DOMAIN (outer_type))
171 return false;
173 /* Nor are conversions from array types with non-constant size to
174 array types with constant size or to different size. */
175 if (TYPE_SIZE (outer_type)
176 && TREE_CODE (TYPE_SIZE (outer_type)) == INTEGER_CST
177 && (!TYPE_SIZE (inner_type)
178 || TREE_CODE (TYPE_SIZE (inner_type)) != INTEGER_CST
179 || !tree_int_cst_equal (TYPE_SIZE (outer_type),
180 TYPE_SIZE (inner_type))))
181 return false;
183 /* Check conversions between arrays with partially known extents.
184 If the array min/max values are constant they have to match.
185 Otherwise allow conversions to unknown and variable extents.
186 In particular this declares conversions that may change the
187 mode to BLKmode as useless. */
188 if (TYPE_DOMAIN (inner_type)
189 && TYPE_DOMAIN (outer_type)
190 && TYPE_DOMAIN (inner_type) != TYPE_DOMAIN (outer_type))
192 tree inner_min = TYPE_MIN_VALUE (TYPE_DOMAIN (inner_type));
193 tree outer_min = TYPE_MIN_VALUE (TYPE_DOMAIN (outer_type));
194 tree inner_max = TYPE_MAX_VALUE (TYPE_DOMAIN (inner_type));
195 tree outer_max = TYPE_MAX_VALUE (TYPE_DOMAIN (outer_type));
197 /* After gimplification a variable min/max value carries no
198 additional information compared to a NULL value. All that
199 matters has been lowered to be part of the IL. */
200 if (inner_min && TREE_CODE (inner_min) != INTEGER_CST)
201 inner_min = NULL_TREE;
202 if (outer_min && TREE_CODE (outer_min) != INTEGER_CST)
203 outer_min = NULL_TREE;
204 if (inner_max && TREE_CODE (inner_max) != INTEGER_CST)
205 inner_max = NULL_TREE;
206 if (outer_max && TREE_CODE (outer_max) != INTEGER_CST)
207 outer_max = NULL_TREE;
209 /* Conversions NULL / variable <- cst are useless, but not
210 the other way around. */
211 if (outer_min
212 && (!inner_min
213 || !tree_int_cst_equal (inner_min, outer_min)))
214 return false;
215 if (outer_max
216 && (!inner_max
217 || !tree_int_cst_equal (inner_max, outer_max)))
218 return false;
221 /* Recurse on the element check. */
222 return useless_type_conversion_p (TREE_TYPE (outer_type),
223 TREE_TYPE (inner_type));
226 else if ((TREE_CODE (inner_type) == FUNCTION_TYPE
227 || TREE_CODE (inner_type) == METHOD_TYPE)
228 && TREE_CODE (inner_type) == TREE_CODE (outer_type))
230 tree outer_parm, inner_parm;
232 /* If the return types are not compatible bail out. */
233 if (!useless_type_conversion_p (TREE_TYPE (outer_type),
234 TREE_TYPE (inner_type)))
235 return false;
237 /* Method types should belong to a compatible base class. */
238 if (TREE_CODE (inner_type) == METHOD_TYPE
239 && !useless_type_conversion_p (TYPE_METHOD_BASETYPE (outer_type),
240 TYPE_METHOD_BASETYPE (inner_type)))
241 return false;
243 /* A conversion to an unprototyped argument list is ok. */
244 if (!prototype_p (outer_type))
245 return true;
247 /* If the unqualified argument types are compatible the conversion
248 is useless. */
249 if (TYPE_ARG_TYPES (outer_type) == TYPE_ARG_TYPES (inner_type))
250 return true;
252 for (outer_parm = TYPE_ARG_TYPES (outer_type),
253 inner_parm = TYPE_ARG_TYPES (inner_type);
254 outer_parm && inner_parm;
255 outer_parm = TREE_CHAIN (outer_parm),
256 inner_parm = TREE_CHAIN (inner_parm))
257 if (!useless_type_conversion_p
258 (TYPE_MAIN_VARIANT (TREE_VALUE (outer_parm)),
259 TYPE_MAIN_VARIANT (TREE_VALUE (inner_parm))))
260 return false;
262 /* If there is a mismatch in the number of arguments the functions
263 are not compatible. */
264 if (outer_parm || inner_parm)
265 return false;
267 /* Defer to the target if necessary. */
268 if (TYPE_ATTRIBUTES (inner_type) || TYPE_ATTRIBUTES (outer_type))
269 return comp_type_attributes (outer_type, inner_type) != 0;
271 return true;
274 /* For aggregates we rely on TYPE_CANONICAL exclusively and require
275 explicit conversions for types involving to be structurally
276 compared types. */
277 else if (AGGREGATE_TYPE_P (inner_type)
278 && TREE_CODE (inner_type) == TREE_CODE (outer_type))
279 return TYPE_CANONICAL (inner_type)
280 && TYPE_CANONICAL (inner_type) == TYPE_CANONICAL (outer_type);
282 else if (TREE_CODE (inner_type) == OFFSET_TYPE
283 && TREE_CODE (outer_type) == OFFSET_TYPE)
284 return useless_type_conversion_p (TREE_TYPE (outer_type),
285 TREE_TYPE (inner_type))
286 && useless_type_conversion_p
287 (TYPE_OFFSET_BASETYPE (outer_type),
288 TYPE_OFFSET_BASETYPE (inner_type));
290 return false;
294 /* ----- Decl related ----- */
296 /* Set sequence SEQ to be the GIMPLE body for function FN. */
298 void
299 gimple_set_body (tree fndecl, gimple_seq seq)
301 struct function *fn = DECL_STRUCT_FUNCTION (fndecl);
302 if (fn == NULL)
304 /* If FNDECL still does not have a function structure associated
305 with it, then it does not make sense for it to receive a
306 GIMPLE body. */
307 gcc_assert (seq == NULL);
309 else
310 fn->gimple_body = seq;
314 /* Return the body of GIMPLE statements for function FN. After the
315 CFG pass, the function body doesn't exist anymore because it has
316 been split up into basic blocks. In this case, it returns
317 NULL. */
319 gimple_seq
320 gimple_body (tree fndecl)
322 struct function *fn = DECL_STRUCT_FUNCTION (fndecl);
323 return fn ? fn->gimple_body : NULL;
326 /* Return true when FNDECL has Gimple body either in unlowered
327 or CFG form. */
328 bool
329 gimple_has_body_p (tree fndecl)
331 struct function *fn = DECL_STRUCT_FUNCTION (fndecl);
332 return (gimple_body (fndecl) || (fn && fn->cfg && !(fn->curr_properties & PROP_rtl)));
335 /* Return a printable name for symbol DECL. */
337 const char *
338 gimple_decl_printable_name (tree decl, int verbosity)
340 if (!DECL_NAME (decl))
341 return NULL;
343 if (HAS_DECL_ASSEMBLER_NAME_P (decl) && DECL_ASSEMBLER_NAME_SET_P (decl))
345 int dmgl_opts = DMGL_NO_OPTS;
347 if (verbosity >= 2)
349 dmgl_opts = DMGL_VERBOSE
350 | DMGL_ANSI
351 | DMGL_GNU_V3
352 | DMGL_RET_POSTFIX;
353 if (TREE_CODE (decl) == FUNCTION_DECL)
354 dmgl_opts |= DMGL_PARAMS;
357 const char *mangled_str
358 = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME_RAW (decl));
359 const char *str = cplus_demangle_v3 (mangled_str, dmgl_opts);
360 return str ? str : mangled_str;
363 return IDENTIFIER_POINTER (DECL_NAME (decl));
367 /* Create a new VAR_DECL and copy information from VAR to it. */
369 tree
370 copy_var_decl (tree var, tree name, tree type)
372 tree copy = build_decl (DECL_SOURCE_LOCATION (var), VAR_DECL, name, type);
374 TREE_ADDRESSABLE (copy) = TREE_ADDRESSABLE (var);
375 TREE_THIS_VOLATILE (copy) = TREE_THIS_VOLATILE (var);
376 DECL_NOT_GIMPLE_REG_P (copy) = DECL_NOT_GIMPLE_REG_P (var);
377 DECL_ARTIFICIAL (copy) = DECL_ARTIFICIAL (var);
378 DECL_IGNORED_P (copy) = DECL_IGNORED_P (var);
379 DECL_CONTEXT (copy) = DECL_CONTEXT (var);
380 TREE_USED (copy) = 1;
381 DECL_SEEN_IN_BIND_EXPR_P (copy) = 1;
382 DECL_ATTRIBUTES (copy) = DECL_ATTRIBUTES (var);
383 if (DECL_USER_ALIGN (var))
385 SET_DECL_ALIGN (copy, DECL_ALIGN (var));
386 DECL_USER_ALIGN (copy) = 1;
389 copy_warning (copy, var);
390 return copy;
393 /* Strip off a legitimate source ending from the input string NAME of
394 length LEN. Rather than having to know the names used by all of
395 our front ends, we strip off an ending of a period followed by
396 up to four characters. (like ".cpp".) */
398 static inline void
399 remove_suffix (char *name, int len)
401 int i;
403 for (i = 2; i < 7 && len > i; i++)
405 if (name[len - i] == '.')
407 name[len - i] = '\0';
408 break;
413 /* Create a new temporary name with PREFIX. Return an identifier. */
415 static GTY(()) unsigned int tmp_var_id_num;
417 tree
418 create_tmp_var_name (const char *prefix)
420 char *tmp_name;
422 if (prefix)
424 char *preftmp = ASTRDUP (prefix);
426 remove_suffix (preftmp, strlen (preftmp));
427 clean_symbol_name (preftmp);
429 prefix = preftmp;
432 ASM_FORMAT_PRIVATE_NAME (tmp_name, prefix ? prefix : "T", tmp_var_id_num++);
433 return get_identifier (tmp_name);
436 /* Create a new temporary variable declaration of type TYPE.
437 Do NOT push it into the current binding. */
439 tree
440 create_tmp_var_raw (tree type, const char *prefix)
442 tree tmp_var;
444 tmp_var = build_decl (input_location,
445 VAR_DECL, prefix ? create_tmp_var_name (prefix) : NULL,
446 type);
448 /* The variable was declared by the compiler. */
449 DECL_ARTIFICIAL (tmp_var) = 1;
450 /* And we don't want debug info for it. */
451 DECL_IGNORED_P (tmp_var) = 1;
452 /* And we don't want even the fancy names of those printed in
453 -fdump-final-insns= dumps. */
454 DECL_NAMELESS (tmp_var) = 1;
456 /* Make the variable writable. */
457 TREE_READONLY (tmp_var) = 0;
459 DECL_EXTERNAL (tmp_var) = 0;
460 TREE_STATIC (tmp_var) = 0;
461 TREE_USED (tmp_var) = 1;
463 return tmp_var;
466 /* Create a new temporary variable declaration of type TYPE. DO push the
467 variable into the current binding. Further, assume that this is called
468 only from gimplification or optimization, at which point the creation of
469 certain types are bugs. */
471 tree
472 create_tmp_var (tree type, const char *prefix)
474 tree tmp_var;
476 /* We don't allow types that are addressable (meaning we can't make copies),
477 or incomplete. We also used to reject every variable size objects here,
478 but now support those for which a constant upper bound can be obtained.
479 The processing for variable sizes is performed in gimple_add_tmp_var,
480 point at which it really matters and possibly reached via paths not going
481 through this function, e.g. after direct calls to create_tmp_var_raw. */
482 gcc_assert (!TREE_ADDRESSABLE (type) && COMPLETE_TYPE_P (type));
484 tmp_var = create_tmp_var_raw (type, prefix);
485 gimple_add_tmp_var (tmp_var);
486 return tmp_var;
489 /* Create a new temporary variable declaration of type TYPE by calling
490 create_tmp_var and if TYPE is a vector or a complex number, mark the new
491 temporary as gimple register. */
493 tree
494 create_tmp_reg (tree type, const char *prefix)
496 return create_tmp_var (type, prefix);
499 /* Create a new temporary variable declaration of type TYPE by calling
500 create_tmp_var and if TYPE is a vector or a complex number, mark the new
501 temporary as gimple register. */
503 tree
504 create_tmp_reg_fn (struct function *fn, tree type, const char *prefix)
506 tree tmp;
508 tmp = create_tmp_var_raw (type, prefix);
509 gimple_add_tmp_var_fn (fn, tmp);
511 return tmp;
515 /* ----- Expression related ----- */
517 /* Extract the operands and code for expression EXPR into *SUBCODE_P,
518 *OP1_P, *OP2_P and *OP3_P respectively. */
520 void
521 extract_ops_from_tree (tree expr, enum tree_code *subcode_p, tree *op1_p,
522 tree *op2_p, tree *op3_p)
524 *subcode_p = TREE_CODE (expr);
525 switch (get_gimple_rhs_class (*subcode_p))
527 case GIMPLE_TERNARY_RHS:
529 *op1_p = TREE_OPERAND (expr, 0);
530 *op2_p = TREE_OPERAND (expr, 1);
531 *op3_p = TREE_OPERAND (expr, 2);
532 break;
534 case GIMPLE_BINARY_RHS:
536 *op1_p = TREE_OPERAND (expr, 0);
537 *op2_p = TREE_OPERAND (expr, 1);
538 *op3_p = NULL_TREE;
539 break;
541 case GIMPLE_UNARY_RHS:
543 *op1_p = TREE_OPERAND (expr, 0);
544 *op2_p = NULL_TREE;
545 *op3_p = NULL_TREE;
546 break;
548 case GIMPLE_SINGLE_RHS:
550 *op1_p = expr;
551 *op2_p = NULL_TREE;
552 *op3_p = NULL_TREE;
553 break;
555 default:
556 gcc_unreachable ();
560 /* Extract operands for a GIMPLE_COND statement out of COND_EXPR tree COND. */
562 void
563 gimple_cond_get_ops_from_tree (tree cond, enum tree_code *code_p,
564 tree *lhs_p, tree *rhs_p)
566 gcc_assert (COMPARISON_CLASS_P (cond)
567 || TREE_CODE (cond) == TRUTH_NOT_EXPR
568 || is_gimple_min_invariant (cond)
569 || SSA_VAR_P (cond));
570 gcc_checking_assert (!tree_could_throw_p (cond));
572 extract_ops_from_tree (cond, code_p, lhs_p, rhs_p);
574 /* Canonicalize conditionals of the form 'if (!VAL)'. */
575 if (*code_p == TRUTH_NOT_EXPR)
577 *code_p = EQ_EXPR;
578 gcc_assert (*lhs_p && *rhs_p == NULL_TREE);
579 *rhs_p = build_zero_cst (TREE_TYPE (*lhs_p));
581 /* Canonicalize conditionals of the form 'if (VAL)' */
582 else if (TREE_CODE_CLASS (*code_p) != tcc_comparison)
584 *code_p = NE_EXPR;
585 gcc_assert (*lhs_p && *rhs_p == NULL_TREE);
586 *rhs_p = build_zero_cst (TREE_TYPE (*lhs_p));
590 /* Return true if T is a valid LHS for a GIMPLE assignment expression. */
592 bool
593 is_gimple_lvalue (tree t)
595 return (is_gimple_addressable (t)
596 || TREE_CODE (t) == WITH_SIZE_EXPR
597 /* These are complex lvalues, but don't have addresses, so they
598 go here. */
599 || TREE_CODE (t) == BIT_FIELD_REF);
602 /* Helper for is_gimple_condexpr and is_gimple_condexpr_for_cond. */
604 static bool
605 is_gimple_condexpr_1 (tree t, bool allow_traps)
607 return (is_gimple_val (t) || (COMPARISON_CLASS_P (t)
608 && (allow_traps || !tree_could_throw_p (t))
609 && is_gimple_val (TREE_OPERAND (t, 0))
610 && is_gimple_val (TREE_OPERAND (t, 1))));
613 /* Return true if T is a GIMPLE condition. */
615 bool
616 is_gimple_condexpr (tree t)
618 return is_gimple_condexpr_1 (t, true);
621 /* Like is_gimple_condexpr, but does not allow T to trap. */
623 bool
624 is_gimple_condexpr_for_cond (tree t)
626 return is_gimple_condexpr_1 (t, false);
629 /* Return true if T is a gimple address. */
631 bool
632 is_gimple_address (const_tree t)
634 tree op;
636 if (TREE_CODE (t) != ADDR_EXPR)
637 return false;
639 op = TREE_OPERAND (t, 0);
640 while (handled_component_p (op))
642 if ((TREE_CODE (op) == ARRAY_REF
643 || TREE_CODE (op) == ARRAY_RANGE_REF)
644 && !is_gimple_val (TREE_OPERAND (op, 1)))
645 return false;
647 op = TREE_OPERAND (op, 0);
650 if (CONSTANT_CLASS_P (op)
651 || TREE_CODE (op) == TARGET_MEM_REF
652 || TREE_CODE (op) == MEM_REF)
653 return true;
655 switch (TREE_CODE (op))
657 case PARM_DECL:
658 case RESULT_DECL:
659 case LABEL_DECL:
660 case FUNCTION_DECL:
661 case VAR_DECL:
662 case CONST_DECL:
663 return true;
665 default:
666 return false;
670 /* Return true if T is a gimple invariant address. */
672 bool
673 is_gimple_invariant_address (const_tree t)
675 const_tree op;
677 if (TREE_CODE (t) != ADDR_EXPR)
678 return false;
680 op = strip_invariant_refs (TREE_OPERAND (t, 0));
681 if (!op)
682 return false;
684 if (TREE_CODE (op) == MEM_REF)
686 const_tree op0 = TREE_OPERAND (op, 0);
687 return (TREE_CODE (op0) == ADDR_EXPR
688 && (CONSTANT_CLASS_P (TREE_OPERAND (op0, 0))
689 || decl_address_invariant_p (TREE_OPERAND (op0, 0))));
692 return CONSTANT_CLASS_P (op) || decl_address_invariant_p (op);
695 /* Return true if T is a gimple invariant address at IPA level
696 (so addresses of variables on stack are not allowed). */
698 bool
699 is_gimple_ip_invariant_address (const_tree t)
701 const_tree op;
703 if (TREE_CODE (t) != ADDR_EXPR)
704 return false;
706 op = strip_invariant_refs (TREE_OPERAND (t, 0));
707 if (!op)
708 return false;
710 if (TREE_CODE (op) == MEM_REF)
712 const_tree op0 = TREE_OPERAND (op, 0);
713 return (TREE_CODE (op0) == ADDR_EXPR
714 && (CONSTANT_CLASS_P (TREE_OPERAND (op0, 0))
715 || decl_address_ip_invariant_p (TREE_OPERAND (op0, 0))));
718 return CONSTANT_CLASS_P (op) || decl_address_ip_invariant_p (op);
721 /* Return true if T is a GIMPLE minimal invariant. It's a restricted
722 form of function invariant. */
724 bool
725 is_gimple_min_invariant (const_tree t)
727 if (TREE_CODE (t) == ADDR_EXPR)
728 return is_gimple_invariant_address (t);
730 return is_gimple_constant (t);
733 /* Return true if T is a GIMPLE interprocedural invariant. It's a restricted
734 form of gimple minimal invariant. */
736 bool
737 is_gimple_ip_invariant (const_tree t)
739 if (TREE_CODE (t) == ADDR_EXPR)
740 return is_gimple_ip_invariant_address (t);
742 return is_gimple_constant (t);
745 /* Return true if T is a non-aggregate register variable. */
747 bool
748 is_gimple_reg (tree t)
750 if (virtual_operand_p (t))
751 return false;
753 if (TREE_CODE (t) == SSA_NAME)
754 return true;
756 if (!is_gimple_variable (t))
757 return false;
759 if (!is_gimple_reg_type (TREE_TYPE (t)))
760 return false;
762 /* A volatile decl is not acceptable because we can't reuse it as
763 needed. We need to copy it into a temp first. */
764 if (TREE_THIS_VOLATILE (t))
765 return false;
767 /* We define "registers" as things that can be renamed as needed,
768 which with our infrastructure does not apply to memory. */
769 if (needs_to_live_in_memory (t))
770 return false;
772 /* Hard register variables are an interesting case. For those that
773 are call-clobbered, we don't know where all the calls are, since
774 we don't (want to) take into account which operations will turn
775 into libcalls at the rtl level. For those that are call-saved,
776 we don't currently model the fact that calls may in fact change
777 global hard registers, nor do we examine ASM_CLOBBERS at the tree
778 level, and so miss variable changes that might imply. All around,
779 it seems safest to not do too much optimization with these at the
780 tree level at all. We'll have to rely on the rtl optimizers to
781 clean this up, as there we've got all the appropriate bits exposed. */
782 if (TREE_CODE (t) == VAR_DECL && DECL_HARD_REGISTER (t))
783 return false;
785 /* Variables can be marked as having partial definitions, avoid
786 putting them into SSA form. */
787 return !DECL_NOT_GIMPLE_REG_P (t);
791 /* Return true if T is a GIMPLE rvalue, i.e. an identifier or a constant. */
793 bool
794 is_gimple_val (tree t)
796 /* Make loads from volatiles and memory vars explicit. */
797 if (is_gimple_variable (t)
798 && is_gimple_reg_type (TREE_TYPE (t))
799 && !is_gimple_reg (t))
800 return false;
802 return (is_gimple_variable (t) || is_gimple_min_invariant (t));
805 /* Similarly, but accept hard registers as inputs to asm statements. */
807 bool
808 is_gimple_asm_val (tree t)
810 if (TREE_CODE (t) == VAR_DECL && DECL_HARD_REGISTER (t))
811 return true;
813 return is_gimple_val (t);
816 /* Return true if T is a GIMPLE minimal lvalue. */
818 bool
819 is_gimple_min_lval (tree t)
821 if (!(t = CONST_CAST_TREE (strip_invariant_refs (t))))
822 return false;
823 return (is_gimple_id (t) || TREE_CODE (t) == MEM_REF);
826 /* Return true if T is a valid function operand of a CALL_EXPR. */
828 bool
829 is_gimple_call_addr (tree t)
831 return (TREE_CODE (t) == OBJ_TYPE_REF || is_gimple_val (t));
834 /* Return true if T is a valid address operand of a MEM_REF. */
836 bool
837 is_gimple_mem_ref_addr (tree t)
839 return (is_gimple_reg (t)
840 || TREE_CODE (t) == INTEGER_CST
841 || (TREE_CODE (t) == ADDR_EXPR
842 && (CONSTANT_CLASS_P (TREE_OPERAND (t, 0))
843 || decl_address_invariant_p (TREE_OPERAND (t, 0)))));
846 /* Hold trees marked addressable during expand. */
848 static hash_set<tree> *mark_addressable_queue;
850 /* Mark X as addressable or queue it up if called during expand. We
851 don't want to apply it immediately during expand because decls are
852 made addressable at that point due to RTL-only concerns, such as
853 uses of memcpy for block moves, and TREE_ADDRESSABLE changes
854 is_gimple_reg, which might make it seem like a variable that used
855 to be a gimple_reg shouldn't have been an SSA name. So we queue up
856 this flag setting and only apply it when we're done with GIMPLE and
857 only RTL issues matter. */
859 static void
860 mark_addressable_1 (tree x)
862 if (!currently_expanding_to_rtl)
864 TREE_ADDRESSABLE (x) = 1;
865 return;
868 if (!mark_addressable_queue)
869 mark_addressable_queue = new hash_set<tree>();
870 mark_addressable_queue->add (x);
873 /* Adaptor for mark_addressable_1 for use in hash_set traversal. */
875 bool
876 mark_addressable_2 (tree const &x, void * ATTRIBUTE_UNUSED = NULL)
878 mark_addressable_1 (x);
879 return false;
882 /* Mark all queued trees as addressable, and empty the queue. To be
883 called right after clearing CURRENTLY_EXPANDING_TO_RTL. */
885 void
886 flush_mark_addressable_queue ()
888 gcc_assert (!currently_expanding_to_rtl);
889 if (mark_addressable_queue)
891 mark_addressable_queue->traverse<void*, mark_addressable_2> (NULL);
892 delete mark_addressable_queue;
893 mark_addressable_queue = NULL;
897 /* Mark X addressable. Unlike the langhook we expect X to be in gimple
898 form and we don't do any syntax checking. */
900 void
901 mark_addressable (tree x)
903 if (TREE_CODE (x) == WITH_SIZE_EXPR)
904 x = TREE_OPERAND (x, 0);
905 while (handled_component_p (x))
906 x = TREE_OPERAND (x, 0);
907 if (TREE_CODE (x) == MEM_REF
908 && TREE_CODE (TREE_OPERAND (x, 0)) == ADDR_EXPR)
909 x = TREE_OPERAND (TREE_OPERAND (x, 0), 0);
910 if (!VAR_P (x)
911 && TREE_CODE (x) != PARM_DECL
912 && TREE_CODE (x) != RESULT_DECL)
913 return;
914 mark_addressable_1 (x);
916 /* Also mark the artificial SSA_NAME that points to the partition of X. */
917 if (TREE_CODE (x) == VAR_DECL
918 && !DECL_EXTERNAL (x)
919 && !TREE_STATIC (x)
920 && cfun->gimple_df != NULL
921 && cfun->gimple_df->decls_to_pointers != NULL)
923 tree *namep = cfun->gimple_df->decls_to_pointers->get (x);
924 if (namep)
925 mark_addressable_1 (*namep);
929 /* Returns true iff T is a valid RHS for an assignment to a renamed
930 user -- or front-end generated artificial -- variable. */
932 bool
933 is_gimple_reg_rhs (tree t)
935 return get_gimple_rhs_class (TREE_CODE (t)) != GIMPLE_INVALID_RHS;
938 #include "gt-gimple-expr.h"