1 /* Tree lowering pass. This pass converts the GENERIC functions-as-trees
2 tree representation into the GIMPLE form.
3 Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4 Major work done by Sebastian Pop <s.pop@laposte.net>,
5 Diego Novillo <dnovillo@redhat.com> and Jason Merrill <jason@redhat.com>.
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify it under
10 the terms of the GNU General Public License as published by the Free
11 Software Foundation; either version 2, or (at your option) any later
14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to the Free
21 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
26 #include "coretypes.h"
31 #include "tree-gimple.h"
32 #include "tree-inline.h"
33 #include "diagnostic.h"
34 #include "langhooks.h"
35 #include "langhooks-def.h"
36 #include "tree-flow.h"
50 static struct gimplify_ctx
52 tree current_bind_expr;
54 tree conditional_cleanups;
57 VEC(tree,heap) *case_labels;
58 /* The formal temporary table. Should this be persistent? */
66 /* Formal (expression) temporary table handling: Multiple occurrences of
67 the same scalar expression are evaluated into the same temporary. */
69 typedef struct gimple_temp_hash_elt
72 tree temp; /* Value */
75 /* Forward declarations. */
76 static enum gimplify_status gimplify_compound_expr (tree *, tree *, bool);
77 #ifdef ENABLE_CHECKING
78 static bool cpt_same_type (tree a, tree b);
82 /* Return a hash value for a formal temporary table entry. */
85 gimple_tree_hash (const void *p)
87 tree t = ((const elt_t *) p)->val;
88 return iterative_hash_expr (t, 0);
91 /* Compare two formal temporary table entries. */
94 gimple_tree_eq (const void *p1, const void *p2)
96 tree t1 = ((const elt_t *) p1)->val;
97 tree t2 = ((const elt_t *) p2)->val;
98 enum tree_code code = TREE_CODE (t1);
100 if (TREE_CODE (t2) != code
101 || TREE_TYPE (t1) != TREE_TYPE (t2))
104 if (!operand_equal_p (t1, t2, 0))
107 /* Only allow them to compare equal if they also hash equal; otherwise
108 results are nondeterminate, and we fail bootstrap comparison. */
109 gcc_assert (gimple_tree_hash (p1) == gimple_tree_hash (p2));
114 /* Set up a context for the gimplifier. */
117 push_gimplify_context (void)
119 gcc_assert (!gimplify_ctxp);
121 = (struct gimplify_ctx *) xcalloc (1, sizeof (struct gimplify_ctx));
123 gimplify_ctxp->temp_htab
124 = htab_create (1000, gimple_tree_hash, gimple_tree_eq, free);
126 gimplify_ctxp->temp_htab = NULL;
129 /* Tear down a context for the gimplifier. If BODY is non-null, then
130 put the temporaries into the outer BIND_EXPR. Otherwise, put them
131 in the unexpanded_var_list. */
134 pop_gimplify_context (tree body)
138 gcc_assert (gimplify_ctxp && !gimplify_ctxp->current_bind_expr);
140 for (t = gimplify_ctxp->temps; t ; t = TREE_CHAIN (t))
141 DECL_GIMPLE_FORMAL_TEMP_P (t) = 0;
144 declare_tmp_vars (gimplify_ctxp->temps, body);
146 record_vars (gimplify_ctxp->temps);
149 if (!quiet_flag && optimize)
150 fprintf (stderr, " collisions: %f ",
151 htab_collisions (gimplify_ctxp->temp_htab));
155 htab_delete (gimplify_ctxp->temp_htab);
156 free (gimplify_ctxp);
157 gimplify_ctxp = NULL;
161 gimple_push_bind_expr (tree bind)
163 TREE_CHAIN (bind) = gimplify_ctxp->current_bind_expr;
164 gimplify_ctxp->current_bind_expr = bind;
168 gimple_pop_bind_expr (void)
170 gimplify_ctxp->current_bind_expr
171 = TREE_CHAIN (gimplify_ctxp->current_bind_expr);
175 gimple_current_bind_expr (void)
177 return gimplify_ctxp->current_bind_expr;
180 /* Returns true iff there is a COND_EXPR between us and the innermost
181 CLEANUP_POINT_EXPR. This info is used by gimple_push_cleanup. */
184 gimple_conditional_context (void)
186 return gimplify_ctxp->conditions > 0;
189 /* Note that we've entered a COND_EXPR. */
192 gimple_push_condition (void)
194 #ifdef ENABLE_CHECKING
195 if (gimplify_ctxp->conditions == 0)
196 gcc_assert (!gimplify_ctxp->conditional_cleanups);
198 ++(gimplify_ctxp->conditions);
201 /* Note that we've left a COND_EXPR. If we're back at unconditional scope
202 now, add any conditional cleanups we've seen to the prequeue. */
205 gimple_pop_condition (tree *pre_p)
207 int conds = --(gimplify_ctxp->conditions);
209 gcc_assert (conds >= 0);
212 append_to_statement_list (gimplify_ctxp->conditional_cleanups, pre_p);
213 gimplify_ctxp->conditional_cleanups = NULL_TREE;
217 /* A subroutine of append_to_statement_list{,_force}. T is not NULL. */
220 append_to_statement_list_1 (tree t, tree *list_p)
223 tree_stmt_iterator i;
227 if (t && TREE_CODE (t) == STATEMENT_LIST)
232 *list_p = list = alloc_stmt_list ();
236 tsi_link_after (&i, t, TSI_CONTINUE_LINKING);
239 /* Add T to the end of the list container pointed to by LIST_P.
240 If T is an expression with no effects, it is ignored. */
243 append_to_statement_list (tree t, tree *list_p)
245 if (t && TREE_SIDE_EFFECTS (t))
246 append_to_statement_list_1 (t, list_p);
249 /* Similar, but the statement is always added, regardless of side effects. */
252 append_to_statement_list_force (tree t, tree *list_p)
255 append_to_statement_list_1 (t, list_p);
258 /* Both gimplify the statement T and append it to LIST_P. */
261 gimplify_and_add (tree t, tree *list_p)
264 append_to_statement_list (t, list_p);
267 /* Strip off a legitimate source ending from the input string NAME of
268 length LEN. Rather than having to know the names used by all of
269 our front ends, we strip off an ending of a period followed by
270 up to five characters. (Java uses ".class".) */
273 remove_suffix (char *name, int len)
277 for (i = 2; i < 8 && len > i; i++)
279 if (name[len - i] == '.')
281 name[len - i] = '\0';
287 /* Create a nameless artificial label and put it in the current function
288 context. Returns the newly created label. */
291 create_artificial_label (void)
293 tree lab = build_decl (LABEL_DECL, NULL_TREE, void_type_node);
295 DECL_ARTIFICIAL (lab) = 1;
296 DECL_IGNORED_P (lab) = 1;
297 DECL_CONTEXT (lab) = current_function_decl;
301 /* Subroutine for find_single_pointer_decl. */
304 find_single_pointer_decl_1 (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
307 tree *pdecl = (tree *) data;
309 if (DECL_P (*tp) && POINTER_TYPE_P (TREE_TYPE (*tp)))
313 /* We already found a pointer decl; return anything other
314 than NULL_TREE to unwind from walk_tree signalling that
315 we have a duplicate. */
324 /* Find the single DECL of pointer type in the tree T and return it.
325 If there are zero or more than one such DECLs, return NULL. */
328 find_single_pointer_decl (tree t)
330 tree decl = NULL_TREE;
332 if (walk_tree (&t, find_single_pointer_decl_1, &decl, NULL))
334 /* find_single_pointer_decl_1 returns a non-zero value, causing
335 walk_tree to return a non-zero value, to indicate that it
336 found more than one pointer DECL. */
343 /* Create a new temporary name with PREFIX. Returns an identifier. */
345 static GTY(()) unsigned int tmp_var_id_num;
348 create_tmp_var_name (const char *prefix)
354 char *preftmp = ASTRDUP (prefix);
356 remove_suffix (preftmp, strlen (preftmp));
360 ASM_FORMAT_PRIVATE_NAME (tmp_name, prefix ? prefix : "T", tmp_var_id_num++);
361 return get_identifier (tmp_name);
365 /* Create a new temporary variable declaration of type TYPE.
366 Does NOT push it into the current binding. */
369 create_tmp_var_raw (tree type, const char *prefix)
374 /* Make the type of the variable writable. */
375 new_type = build_type_variant (type, 0, 0);
376 TYPE_ATTRIBUTES (new_type) = TYPE_ATTRIBUTES (type);
378 tmp_var = build_decl (VAR_DECL, prefix ? create_tmp_var_name (prefix) : NULL,
381 /* The variable was declared by the compiler. */
382 DECL_ARTIFICIAL (tmp_var) = 1;
383 /* And we don't want debug info for it. */
384 DECL_IGNORED_P (tmp_var) = 1;
386 /* Make the variable writable. */
387 TREE_READONLY (tmp_var) = 0;
389 DECL_EXTERNAL (tmp_var) = 0;
390 TREE_STATIC (tmp_var) = 0;
391 TREE_USED (tmp_var) = 1;
396 /* Create a new temporary variable declaration of type TYPE. DOES push the
397 variable into the current binding. Further, assume that this is called
398 only from gimplification or optimization, at which point the creation of
399 certain types are bugs. */
402 create_tmp_var (tree type, const char *prefix)
406 /* We don't allow types that are addressable (meaning we can't make copies),
407 incomplete, or of variable size. */
408 gcc_assert (!TREE_ADDRESSABLE (type)
409 && COMPLETE_TYPE_P (type)
410 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST);
412 tmp_var = create_tmp_var_raw (type, prefix);
413 gimple_add_tmp_var (tmp_var);
417 /* Given a tree, try to return a useful variable name that we can use
418 to prefix a temporary that is being assigned the value of the tree.
419 I.E. given <temp> = &A, return A. */
427 STRIP_NOPS (stripped_decl);
428 if (DECL_P (stripped_decl) && DECL_NAME (stripped_decl))
429 return IDENTIFIER_POINTER (DECL_NAME (stripped_decl));
432 switch (TREE_CODE (stripped_decl))
435 return get_name (TREE_OPERAND (stripped_decl, 0));
443 /* Create a temporary with a name derived from VAL. Subroutine of
444 lookup_tmp_var; nobody else should call this function. */
447 create_tmp_from_val (tree val)
449 return create_tmp_var (TYPE_MAIN_VARIANT (TREE_TYPE (val)), get_name (val));
452 /* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse
453 an existing expression temporary. */
456 lookup_tmp_var (tree val, bool is_formal)
460 /* If not optimizing, never really reuse a temporary. local-alloc
461 won't allocate any variable that is used in more than one basic
462 block, which means it will go into memory, causing much extra
463 work in reload and final and poorer code generation, outweighing
464 the extra memory allocation here. */
465 if (!optimize || !is_formal || TREE_SIDE_EFFECTS (val))
466 ret = create_tmp_from_val (val);
473 slot = htab_find_slot (gimplify_ctxp->temp_htab, (void *)&elt, INSERT);
476 elt_p = xmalloc (sizeof (*elt_p));
478 elt_p->temp = ret = create_tmp_from_val (val);
479 *slot = (void *) elt_p;
483 elt_p = (elt_t *) *slot;
489 DECL_GIMPLE_FORMAL_TEMP_P (ret) = 1;
494 /* Returns a formal temporary variable initialized with VAL. PRE_P is as
495 in gimplify_expr. Only use this function if:
497 1) The value of the unfactored expression represented by VAL will not
498 change between the initialization and use of the temporary, and
499 2) The temporary will not be otherwise modified.
501 For instance, #1 means that this is inappropriate for SAVE_EXPR temps,
502 and #2 means it is inappropriate for && temps.
504 For other cases, use get_initialized_tmp_var instead. */
507 internal_get_tmp_var (tree val, tree *pre_p, tree *post_p, bool is_formal)
511 gimplify_expr (&val, pre_p, post_p, is_gimple_formal_tmp_rhs, fb_rvalue);
513 t = lookup_tmp_var (val, is_formal);
517 tree u = find_single_pointer_decl (val);
519 if (u && TREE_CODE (u) == VAR_DECL && DECL_BASED_ON_RESTRICT_P (u))
520 u = DECL_GET_RESTRICT_BASE (u);
521 if (u && TYPE_RESTRICT (TREE_TYPE (u)))
523 if (DECL_BASED_ON_RESTRICT_P (t))
524 gcc_assert (u == DECL_GET_RESTRICT_BASE (t));
527 DECL_BASED_ON_RESTRICT_P (t) = 1;
528 SET_DECL_RESTRICT_BASE (t, u);
533 if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE)
534 DECL_COMPLEX_GIMPLE_REG_P (t) = 1;
536 mod = build2 (INIT_EXPR, TREE_TYPE (t), t, val);
538 if (EXPR_HAS_LOCATION (val))
539 SET_EXPR_LOCUS (mod, EXPR_LOCUS (val));
541 SET_EXPR_LOCATION (mod, input_location);
543 /* gimplify_modify_expr might want to reduce this further. */
544 gimplify_and_add (mod, pre_p);
546 /* If we're gimplifying into ssa, gimplify_modify_expr will have
547 given our temporary an ssa name. Find and return it. */
548 if (gimplify_ctxp->into_ssa)
549 t = TREE_OPERAND (mod, 0);
555 get_formal_tmp_var (tree val, tree *pre_p)
557 return internal_get_tmp_var (val, pre_p, NULL, true);
560 /* Returns a temporary variable initialized with VAL. PRE_P and POST_P
561 are as in gimplify_expr. */
564 get_initialized_tmp_var (tree val, tree *pre_p, tree *post_p)
566 return internal_get_tmp_var (val, pre_p, post_p, false);
569 /* Declares all the variables in VARS in SCOPE. */
572 declare_tmp_vars (tree vars, tree scope)
579 /* C99 mode puts the default 'return 0;' for main outside the outer
580 braces. So drill down until we find an actual scope. */
581 while (TREE_CODE (scope) == COMPOUND_EXPR)
582 scope = TREE_OPERAND (scope, 0);
584 gcc_assert (TREE_CODE (scope) == BIND_EXPR);
586 temps = nreverse (last);
587 TREE_CHAIN (last) = BIND_EXPR_VARS (scope);
588 BIND_EXPR_VARS (scope) = temps;
593 gimple_add_tmp_var (tree tmp)
595 gcc_assert (!TREE_CHAIN (tmp) && !DECL_SEEN_IN_BIND_EXPR_P (tmp));
597 DECL_CONTEXT (tmp) = current_function_decl;
598 DECL_SEEN_IN_BIND_EXPR_P (tmp) = 1;
602 TREE_CHAIN (tmp) = gimplify_ctxp->temps;
603 gimplify_ctxp->temps = tmp;
608 declare_tmp_vars (tmp, DECL_SAVED_TREE (current_function_decl));
611 /* Determines whether to assign a locus to the statement STMT. */
614 should_carry_locus_p (tree stmt)
616 /* Don't emit a line note for a label. We particularly don't want to
617 emit one for the break label, since it doesn't actually correspond
618 to the beginning of the loop/switch. */
619 if (TREE_CODE (stmt) == LABEL_EXPR)
622 /* Do not annotate empty statements, since it confuses gcov. */
623 if (!TREE_SIDE_EFFECTS (stmt))
630 annotate_one_with_locus (tree t, location_t locus)
632 if (EXPR_P (t) && ! EXPR_HAS_LOCATION (t) && should_carry_locus_p (t))
633 SET_EXPR_LOCATION (t, locus);
637 annotate_all_with_locus (tree *stmt_p, location_t locus)
639 tree_stmt_iterator i;
644 for (i = tsi_start (*stmt_p); !tsi_end_p (i); tsi_next (&i))
646 tree t = tsi_stmt (i);
648 /* Assuming we've already been gimplified, we shouldn't
649 see nested chaining constructs anymore. */
650 gcc_assert (TREE_CODE (t) != STATEMENT_LIST
651 && TREE_CODE (t) != COMPOUND_EXPR);
653 annotate_one_with_locus (t, locus);
657 /* Similar to copy_tree_r() but do not copy SAVE_EXPR or TARGET_EXPR nodes.
658 These nodes model computations that should only be done once. If we
659 were to unshare something like SAVE_EXPR(i++), the gimplification
660 process would create wrong code. */
663 mostly_copy_tree_r (tree *tp, int *walk_subtrees, void *data)
665 enum tree_code code = TREE_CODE (*tp);
666 /* Don't unshare types, decls, constants and SAVE_EXPR nodes. */
667 if (TREE_CODE_CLASS (code) == tcc_type
668 || TREE_CODE_CLASS (code) == tcc_declaration
669 || TREE_CODE_CLASS (code) == tcc_constant
670 || code == SAVE_EXPR || code == TARGET_EXPR
671 /* We can't do anything sensible with a BLOCK used as an expression,
672 but we also can't just die when we see it because of non-expression
673 uses. So just avert our eyes and cross our fingers. Silly Java. */
678 gcc_assert (code != BIND_EXPR);
679 copy_tree_r (tp, walk_subtrees, data);
685 /* Callback for walk_tree to unshare most of the shared trees rooted at
686 *TP. If *TP has been visited already (i.e., TREE_VISITED (*TP) == 1),
687 then *TP is deep copied by calling copy_tree_r.
689 This unshares the same trees as copy_tree_r with the exception of
690 SAVE_EXPR nodes. These nodes model computations that should only be
691 done once. If we were to unshare something like SAVE_EXPR(i++), the
692 gimplification process would create wrong code. */
695 copy_if_shared_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
696 void *data ATTRIBUTE_UNUSED)
699 enum tree_code code = TREE_CODE (t);
701 /* Skip types, decls, and constants. But we do want to look at their
702 types and the bounds of types. Mark them as visited so we properly
703 unmark their subtrees on the unmark pass. If we've already seen them,
704 don't look down further. */
705 if (TREE_CODE_CLASS (code) == tcc_type
706 || TREE_CODE_CLASS (code) == tcc_declaration
707 || TREE_CODE_CLASS (code) == tcc_constant)
709 if (TREE_VISITED (t))
712 TREE_VISITED (t) = 1;
715 /* If this node has been visited already, unshare it and don't look
717 else if (TREE_VISITED (t))
719 walk_tree (tp, mostly_copy_tree_r, NULL, NULL);
723 /* Otherwise, mark the tree as visited and keep looking. */
725 TREE_VISITED (t) = 1;
731 unmark_visited_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
732 void *data ATTRIBUTE_UNUSED)
734 if (TREE_VISITED (*tp))
735 TREE_VISITED (*tp) = 0;
742 /* Unshare all the trees in BODY_P, a pointer into the body of FNDECL, and the
743 bodies of any nested functions if we are unsharing the entire body of
747 unshare_body (tree *body_p, tree fndecl)
749 struct cgraph_node *cgn = cgraph_node (fndecl);
751 walk_tree (body_p, copy_if_shared_r, NULL, NULL);
752 if (body_p == &DECL_SAVED_TREE (fndecl))
753 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
754 unshare_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
757 /* Likewise, but mark all trees as not visited. */
760 unvisit_body (tree *body_p, tree fndecl)
762 struct cgraph_node *cgn = cgraph_node (fndecl);
764 walk_tree (body_p, unmark_visited_r, NULL, NULL);
765 if (body_p == &DECL_SAVED_TREE (fndecl))
766 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
767 unvisit_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
770 /* Unshare T and all the trees reached from T via TREE_CHAIN. */
773 unshare_all_trees (tree t)
775 walk_tree (&t, copy_if_shared_r, NULL, NULL);
776 walk_tree (&t, unmark_visited_r, NULL, NULL);
779 /* Unconditionally make an unshared copy of EXPR. This is used when using
780 stored expressions which span multiple functions, such as BINFO_VTABLE,
781 as the normal unsharing process can't tell that they're shared. */
784 unshare_expr (tree expr)
786 walk_tree (&expr, mostly_copy_tree_r, NULL, NULL);
790 /* A terser interface for building a representation of an exception
794 gimple_build_eh_filter (tree body, tree allowed, tree failure)
798 /* FIXME should the allowed types go in TREE_TYPE? */
799 t = build (EH_FILTER_EXPR, void_type_node, allowed, NULL_TREE);
800 append_to_statement_list (failure, &EH_FILTER_FAILURE (t));
802 t = build (TRY_CATCH_EXPR, void_type_node, NULL_TREE, t);
803 append_to_statement_list (body, &TREE_OPERAND (t, 0));
809 /* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
810 contain statements and have a value. Assign its value to a temporary
811 and give it void_type_node. Returns the temporary, or NULL_TREE if
812 WRAPPER was already void. */
815 voidify_wrapper_expr (tree wrapper, tree temp)
817 if (!VOID_TYPE_P (TREE_TYPE (wrapper)))
819 tree *p, sub = wrapper;
822 /* Set p to point to the body of the wrapper. */
823 switch (TREE_CODE (sub))
826 /* For a BIND_EXPR, the body is operand 1. */
827 p = &BIND_EXPR_BODY (sub);
831 p = &TREE_OPERAND (sub, 0);
835 /* Advance to the last statement. Set all container types to void. */
836 if (TREE_CODE (*p) == STATEMENT_LIST)
838 tree_stmt_iterator i = tsi_last (*p);
839 p = tsi_end_p (i) ? NULL : tsi_stmt_ptr (i);
843 for (; TREE_CODE (*p) == COMPOUND_EXPR; p = &TREE_OPERAND (*p, 1))
845 TREE_SIDE_EFFECTS (*p) = 1;
846 TREE_TYPE (*p) = void_type_node;
850 if (p == NULL || IS_EMPTY_STMT (*p))
852 /* Look through exception handling. */
853 else if (TREE_CODE (*p) == TRY_FINALLY_EXPR
854 || TREE_CODE (*p) == TRY_CATCH_EXPR)
859 /* The C++ frontend already did this for us. */
860 else if (TREE_CODE (*p) == INIT_EXPR
861 || TREE_CODE (*p) == TARGET_EXPR)
862 temp = TREE_OPERAND (*p, 0);
863 /* If we're returning a dereference, move the dereference
864 outside the wrapper. */
865 else if (TREE_CODE (*p) == INDIRECT_REF)
867 tree ptr = TREE_OPERAND (*p, 0);
868 temp = create_tmp_var (TREE_TYPE (ptr), "retval");
869 *p = build (MODIFY_EXPR, TREE_TYPE (ptr), temp, ptr);
870 temp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (temp)), temp);
871 /* If this is a BIND_EXPR for a const inline function, it might not
872 have TREE_SIDE_EFFECTS set. That is no longer accurate. */
873 TREE_SIDE_EFFECTS (wrapper) = 1;
878 temp = create_tmp_var (TREE_TYPE (wrapper), "retval");
879 *p = build (MODIFY_EXPR, TREE_TYPE (temp), temp, *p);
880 TREE_SIDE_EFFECTS (wrapper) = 1;
883 TREE_TYPE (wrapper) = void_type_node;
890 /* Prepare calls to builtins to SAVE and RESTORE the stack as well as
891 a temporary through which they communicate. */
894 build_stack_save_restore (tree *save, tree *restore)
896 tree save_call, tmp_var;
899 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_SAVE],
901 tmp_var = create_tmp_var (ptr_type_node, "saved_stack");
903 *save = build (MODIFY_EXPR, ptr_type_node, tmp_var, save_call);
905 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_RESTORE],
906 tree_cons (NULL_TREE, tmp_var, NULL_TREE));
909 /* Gimplify a BIND_EXPR. Just voidify and recurse. */
911 static enum gimplify_status
912 gimplify_bind_expr (tree *expr_p, tree temp, tree *pre_p)
914 tree bind_expr = *expr_p;
915 bool old_save_stack = gimplify_ctxp->save_stack;
918 temp = voidify_wrapper_expr (bind_expr, temp);
920 /* Mark variables seen in this bind expr. */
921 for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t))
923 if (TREE_CODE (t) == VAR_DECL)
924 DECL_SEEN_IN_BIND_EXPR_P (t) = 1;
926 /* Preliminarily mark non-addressed complex variables as eligible
927 for promotion to gimple registers. We'll transform their uses
929 if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE
930 && !TREE_THIS_VOLATILE (t)
931 && (TREE_CODE (t) == VAR_DECL && !DECL_HARD_REGISTER (t))
932 && !needs_to_live_in_memory (t))
933 DECL_COMPLEX_GIMPLE_REG_P (t) = 1;
936 gimple_push_bind_expr (bind_expr);
937 gimplify_ctxp->save_stack = false;
939 gimplify_to_stmt_list (&BIND_EXPR_BODY (bind_expr));
941 if (gimplify_ctxp->save_stack)
943 tree stack_save, stack_restore;
945 /* Save stack on entry and restore it on exit. Add a try_finally
946 block to achieve this. Note that mudflap depends on the
947 format of the emitted code: see mx_register_decls(). */
948 build_stack_save_restore (&stack_save, &stack_restore);
950 t = build (TRY_FINALLY_EXPR, void_type_node,
951 BIND_EXPR_BODY (bind_expr), NULL_TREE);
952 append_to_statement_list (stack_restore, &TREE_OPERAND (t, 1));
954 BIND_EXPR_BODY (bind_expr) = NULL_TREE;
955 append_to_statement_list (stack_save, &BIND_EXPR_BODY (bind_expr));
956 append_to_statement_list (t, &BIND_EXPR_BODY (bind_expr));
959 gimplify_ctxp->save_stack = old_save_stack;
960 gimple_pop_bind_expr ();
965 append_to_statement_list (bind_expr, pre_p);
972 /* Gimplify a RETURN_EXPR. If the expression to be returned is not a
973 GIMPLE value, it is assigned to a new temporary and the statement is
974 re-written to return the temporary.
976 PRE_P points to the list where side effects that must happen before
977 STMT should be stored. */
979 static enum gimplify_status
980 gimplify_return_expr (tree stmt, tree *pre_p)
982 tree ret_expr = TREE_OPERAND (stmt, 0);
983 tree result_decl, result;
985 if (!ret_expr || TREE_CODE (ret_expr) == RESULT_DECL
986 || ret_expr == error_mark_node)
989 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
990 result_decl = NULL_TREE;
993 result_decl = TREE_OPERAND (ret_expr, 0);
994 if (TREE_CODE (result_decl) == INDIRECT_REF)
995 /* See through a return by reference. */
996 result_decl = TREE_OPERAND (result_decl, 0);
998 gcc_assert ((TREE_CODE (ret_expr) == MODIFY_EXPR
999 || TREE_CODE (ret_expr) == INIT_EXPR)
1000 && TREE_CODE (result_decl) == RESULT_DECL);
1003 /* If aggregate_value_p is true, then we can return the bare RESULT_DECL.
1004 Recall that aggregate_value_p is FALSE for any aggregate type that is
1005 returned in registers. If we're returning values in registers, then
1006 we don't want to extend the lifetime of the RESULT_DECL, particularly
1007 across another call. In addition, for those aggregates for which
1008 hard_function_value generates a PARALLEL, we'll die during normal
1009 expansion of structure assignments; there's special code in expand_return
1010 to handle this case that does not exist in expand_expr. */
1012 || aggregate_value_p (result_decl, TREE_TYPE (current_function_decl)))
1013 result = result_decl;
1014 else if (gimplify_ctxp->return_temp)
1015 result = gimplify_ctxp->return_temp;
1018 result = create_tmp_var (TREE_TYPE (result_decl), NULL);
1020 /* ??? With complex control flow (usually involving abnormal edges),
1021 we can wind up warning about an uninitialized value for this. Due
1022 to how this variable is constructed and initialized, this is never
1023 true. Give up and never warn. */
1024 TREE_NO_WARNING (result) = 1;
1026 gimplify_ctxp->return_temp = result;
1029 /* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
1030 Then gimplify the whole thing. */
1031 if (result != result_decl)
1032 TREE_OPERAND (ret_expr, 0) = result;
1034 gimplify_and_add (TREE_OPERAND (stmt, 0), pre_p);
1036 /* If we didn't use a temporary, then the result is just the result_decl.
1037 Otherwise we need a simple copy. This should already be gimple. */
1038 if (result == result_decl)
1041 ret_expr = build (MODIFY_EXPR, TREE_TYPE (result), result_decl, result);
1042 TREE_OPERAND (stmt, 0) = ret_expr;
1047 /* Gimplifies a DECL_EXPR node *STMT_P by making any necessary allocation
1048 and initialization explicit. */
1050 static enum gimplify_status
1051 gimplify_decl_expr (tree *stmt_p)
1053 tree stmt = *stmt_p;
1054 tree decl = DECL_EXPR_DECL (stmt);
1056 *stmt_p = NULL_TREE;
1058 if (TREE_TYPE (decl) == error_mark_node)
1061 if ((TREE_CODE (decl) == TYPE_DECL
1062 || TREE_CODE (decl) == VAR_DECL)
1063 && !TYPE_SIZES_GIMPLIFIED (TREE_TYPE (decl)))
1064 gimplify_type_sizes (TREE_TYPE (decl), stmt_p);
1066 if (TREE_CODE (decl) == VAR_DECL && !DECL_EXTERNAL (decl))
1068 tree init = DECL_INITIAL (decl);
1070 if (!TREE_CONSTANT (DECL_SIZE (decl)))
1072 /* This is a variable-sized decl. Simplify its size and mark it
1073 for deferred expansion. Note that mudflap depends on the format
1074 of the emitted code: see mx_register_decls(). */
1075 tree t, args, addr, ptr_type;
1077 gimplify_one_sizepos (&DECL_SIZE (decl), stmt_p);
1078 gimplify_one_sizepos (&DECL_SIZE_UNIT (decl), stmt_p);
1080 /* All occurrences of this decl in final gimplified code will be
1081 replaced by indirection. Setting DECL_VALUE_EXPR does two
1082 things: First, it lets the rest of the gimplifier know what
1083 replacement to use. Second, it lets the debug info know
1084 where to find the value. */
1085 ptr_type = build_pointer_type (TREE_TYPE (decl));
1086 addr = create_tmp_var (ptr_type, get_name (decl));
1087 DECL_IGNORED_P (addr) = 0;
1088 t = build_fold_indirect_ref (addr);
1089 SET_DECL_VALUE_EXPR (decl, t);
1090 DECL_HAS_VALUE_EXPR_P (decl) = 1;
1092 args = tree_cons (NULL, DECL_SIZE_UNIT (decl), NULL);
1093 t = built_in_decls[BUILT_IN_ALLOCA];
1094 t = build_function_call_expr (t, args);
1095 t = fold_convert (ptr_type, t);
1096 t = build2 (MODIFY_EXPR, void_type_node, addr, t);
1098 gimplify_and_add (t, stmt_p);
1100 /* Indicate that we need to restore the stack level when the
1101 enclosing BIND_EXPR is exited. */
1102 gimplify_ctxp->save_stack = true;
1105 if (init && init != error_mark_node)
1107 if (!TREE_STATIC (decl))
1109 DECL_INITIAL (decl) = NULL_TREE;
1110 init = build2 (INIT_EXPR, void_type_node, decl, init);
1111 gimplify_and_add (init, stmt_p);
1114 /* We must still examine initializers for static variables
1115 as they may contain a label address. */
1116 walk_tree (&init, force_labels_r, NULL, NULL);
1119 /* This decl isn't mentioned in the enclosing block, so add it to the
1120 list of temps. FIXME it seems a bit of a kludge to say that
1121 anonymous artificial vars aren't pushed, but everything else is. */
1122 if (DECL_ARTIFICIAL (decl) && DECL_NAME (decl) == NULL_TREE)
1123 gimple_add_tmp_var (decl);
1129 /* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body
1130 and replacing the LOOP_EXPR with goto, but if the loop contains an
1131 EXIT_EXPR, we need to append a label for it to jump to. */
1133 static enum gimplify_status
1134 gimplify_loop_expr (tree *expr_p, tree *pre_p)
1136 tree saved_label = gimplify_ctxp->exit_label;
1137 tree start_label = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
1138 tree jump_stmt = build_and_jump (&LABEL_EXPR_LABEL (start_label));
1140 append_to_statement_list (start_label, pre_p);
1142 gimplify_ctxp->exit_label = NULL_TREE;
1144 gimplify_and_add (LOOP_EXPR_BODY (*expr_p), pre_p);
1146 if (gimplify_ctxp->exit_label)
1148 append_to_statement_list (jump_stmt, pre_p);
1149 *expr_p = build1 (LABEL_EXPR, void_type_node, gimplify_ctxp->exit_label);
1152 *expr_p = jump_stmt;
1154 gimplify_ctxp->exit_label = saved_label;
1159 /* Compare two case labels. Because the front end should already have
1160 made sure that case ranges do not overlap, it is enough to only compare
1161 the CASE_LOW values of each case label. */
1164 compare_case_labels (const void *p1, const void *p2)
1166 tree case1 = *(tree *)p1;
1167 tree case2 = *(tree *)p2;
1169 return tree_int_cst_compare (CASE_LOW (case1), CASE_LOW (case2));
1172 /* Sort the case labels in LABEL_VEC in place in ascending order. */
1175 sort_case_labels (tree label_vec)
1177 size_t len = TREE_VEC_LENGTH (label_vec);
1178 tree default_case = TREE_VEC_ELT (label_vec, len - 1);
1180 if (CASE_LOW (default_case))
1184 /* The last label in the vector should be the default case
1186 for (i = 0; i < len; ++i)
1188 tree t = TREE_VEC_ELT (label_vec, i);
1192 TREE_VEC_ELT (label_vec, i) = TREE_VEC_ELT (label_vec, len - 1);
1193 TREE_VEC_ELT (label_vec, len - 1) = default_case;
1199 qsort (&TREE_VEC_ELT (label_vec, 0), len - 1, sizeof (tree),
1200 compare_case_labels);
1203 /* Gimplify a SWITCH_EXPR, and collect a TREE_VEC of the labels it can
1206 static enum gimplify_status
1207 gimplify_switch_expr (tree *expr_p, tree *pre_p)
1209 tree switch_expr = *expr_p;
1210 enum gimplify_status ret;
1212 ret = gimplify_expr (&SWITCH_COND (switch_expr), pre_p, NULL,
1213 is_gimple_val, fb_rvalue);
1215 if (SWITCH_BODY (switch_expr))
1217 VEC(tree,heap) *labels, *saved_labels;
1218 tree label_vec, default_case = NULL_TREE;
1221 /* If someone can be bothered to fill in the labels, they can
1222 be bothered to null out the body too. */
1223 gcc_assert (!SWITCH_LABELS (switch_expr));
1225 saved_labels = gimplify_ctxp->case_labels;
1226 gimplify_ctxp->case_labels = VEC_alloc (tree, heap, 8);
1228 gimplify_to_stmt_list (&SWITCH_BODY (switch_expr));
1230 labels = gimplify_ctxp->case_labels;
1231 gimplify_ctxp->case_labels = saved_labels;
1233 len = VEC_length (tree, labels);
1235 for (i = 0; i < len; ++i)
1237 tree t = VEC_index (tree, labels, i);
1240 /* The default case must be the last label in the list. */
1242 VEC_replace (tree, labels, i, VEC_index (tree, labels, len - 1));
1248 label_vec = make_tree_vec (len + 1);
1249 SWITCH_LABELS (*expr_p) = label_vec;
1250 append_to_statement_list (switch_expr, pre_p);
1254 /* If the switch has no default label, add one, so that we jump
1255 around the switch body. */
1256 default_case = build (CASE_LABEL_EXPR, void_type_node, NULL_TREE,
1257 NULL_TREE, create_artificial_label ());
1258 append_to_statement_list (SWITCH_BODY (switch_expr), pre_p);
1259 *expr_p = build (LABEL_EXPR, void_type_node,
1260 CASE_LABEL (default_case));
1263 *expr_p = SWITCH_BODY (switch_expr);
1265 for (i = 0; i < len; ++i)
1266 TREE_VEC_ELT (label_vec, i) = VEC_index (tree, labels, i);
1267 TREE_VEC_ELT (label_vec, len) = default_case;
1269 VEC_free (tree, heap, labels);
1271 sort_case_labels (label_vec);
1273 SWITCH_BODY (switch_expr) = NULL;
1276 gcc_assert (SWITCH_LABELS (switch_expr));
1281 static enum gimplify_status
1282 gimplify_case_label_expr (tree *expr_p)
1284 tree expr = *expr_p;
1286 gcc_assert (gimplify_ctxp->case_labels);
1287 VEC_safe_push (tree, heap, gimplify_ctxp->case_labels, expr);
1288 *expr_p = build (LABEL_EXPR, void_type_node, CASE_LABEL (expr));
1292 /* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
1296 build_and_jump (tree *label_p)
1298 if (label_p == NULL)
1299 /* If there's nowhere to jump, just fall through. */
1302 if (*label_p == NULL_TREE)
1304 tree label = create_artificial_label ();
1308 return build1 (GOTO_EXPR, void_type_node, *label_p);
1311 /* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
1312 This also involves building a label to jump to and communicating it to
1313 gimplify_loop_expr through gimplify_ctxp->exit_label. */
1315 static enum gimplify_status
1316 gimplify_exit_expr (tree *expr_p)
1318 tree cond = TREE_OPERAND (*expr_p, 0);
1321 expr = build_and_jump (&gimplify_ctxp->exit_label);
1322 expr = build (COND_EXPR, void_type_node, cond, expr, NULL_TREE);
1328 /* A helper function to be called via walk_tree. Mark all labels under *TP
1329 as being forced. To be called for DECL_INITIAL of static variables. */
1332 force_labels_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1336 if (TREE_CODE (*tp) == LABEL_DECL)
1337 FORCED_LABEL (*tp) = 1;
1342 /* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is
1343 different from its canonical type, wrap the whole thing inside a
1344 NOP_EXPR and force the type of the COMPONENT_REF to be the canonical
1347 The canonical type of a COMPONENT_REF is the type of the field being
1348 referenced--unless the field is a bit-field which can be read directly
1349 in a smaller mode, in which case the canonical type is the
1350 sign-appropriate type corresponding to that mode. */
1353 canonicalize_component_ref (tree *expr_p)
1355 tree expr = *expr_p;
1358 gcc_assert (TREE_CODE (expr) == COMPONENT_REF);
1360 if (INTEGRAL_TYPE_P (TREE_TYPE (expr)))
1361 type = TREE_TYPE (get_unwidened (expr, NULL_TREE));
1363 type = TREE_TYPE (TREE_OPERAND (expr, 1));
1365 if (TREE_TYPE (expr) != type)
1367 tree old_type = TREE_TYPE (expr);
1369 /* Set the type of the COMPONENT_REF to the underlying type. */
1370 TREE_TYPE (expr) = type;
1372 /* And wrap the whole thing inside a NOP_EXPR. */
1373 expr = build1 (NOP_EXPR, old_type, expr);
1379 /* If a NOP conversion is changing a pointer to array of foo to a pointer
1380 to foo, embed that change in the ADDR_EXPR by converting
1385 where L is the lower bound. For simplicity, only do this for constant
1389 canonicalize_addr_expr (tree *expr_p)
1391 tree expr = *expr_p;
1392 tree ctype = TREE_TYPE (expr);
1393 tree addr_expr = TREE_OPERAND (expr, 0);
1394 tree atype = TREE_TYPE (addr_expr);
1395 tree dctype, datype, ddatype, otype, obj_expr;
1397 /* Both cast and addr_expr types should be pointers. */
1398 if (!POINTER_TYPE_P (ctype) || !POINTER_TYPE_P (atype))
1401 /* The addr_expr type should be a pointer to an array. */
1402 datype = TREE_TYPE (atype);
1403 if (TREE_CODE (datype) != ARRAY_TYPE)
1406 /* Both cast and addr_expr types should address the same object type. */
1407 dctype = TREE_TYPE (ctype);
1408 ddatype = TREE_TYPE (datype);
1409 if (!lang_hooks.types_compatible_p (ddatype, dctype))
1412 /* The addr_expr and the object type should match. */
1413 obj_expr = TREE_OPERAND (addr_expr, 0);
1414 otype = TREE_TYPE (obj_expr);
1415 if (!lang_hooks.types_compatible_p (otype, datype))
1418 /* The lower bound and element sizes must be constant. */
1419 if (!TYPE_SIZE_UNIT (dctype)
1420 || TREE_CODE (TYPE_SIZE_UNIT (dctype)) != INTEGER_CST
1421 || !TYPE_DOMAIN (datype) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype))
1422 || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype))) != INTEGER_CST)
1425 /* All checks succeeded. Build a new node to merge the cast. */
1426 *expr_p = build4 (ARRAY_REF, dctype, obj_expr,
1427 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1428 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1429 size_binop (EXACT_DIV_EXPR, TYPE_SIZE_UNIT (dctype),
1430 size_int (TYPE_ALIGN_UNIT (dctype))));
1431 *expr_p = build1 (ADDR_EXPR, ctype, *expr_p);
1434 /* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
1435 underneath as appropriate. */
1437 static enum gimplify_status
1438 gimplify_conversion (tree *expr_p)
1440 gcc_assert (TREE_CODE (*expr_p) == NOP_EXPR
1441 || TREE_CODE (*expr_p) == CONVERT_EXPR);
1443 /* Then strip away all but the outermost conversion. */
1444 STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0));
1446 /* And remove the outermost conversion if it's useless. */
1447 if (tree_ssa_useless_type_conversion (*expr_p))
1448 *expr_p = TREE_OPERAND (*expr_p, 0);
1450 /* If we still have a conversion at the toplevel,
1451 then canonicalize some constructs. */
1452 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1454 tree sub = TREE_OPERAND (*expr_p, 0);
1456 /* If a NOP conversion is changing the type of a COMPONENT_REF
1457 expression, then canonicalize its type now in order to expose more
1458 redundant conversions. */
1459 if (TREE_CODE (sub) == COMPONENT_REF)
1460 canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0));
1462 /* If a NOP conversion is changing a pointer to array of foo
1463 to a pointer to foo, embed that change in the ADDR_EXPR. */
1464 else if (TREE_CODE (sub) == ADDR_EXPR)
1465 canonicalize_addr_expr (expr_p);
1471 /* Gimplify a VAR_DECL or PARM_DECL. Returns GS_OK if we expanded a
1472 DECL_VALUE_EXPR, and it's worth re-examining things. */
1474 static enum gimplify_status
1475 gimplify_var_or_parm_decl (tree *expr_p)
1477 tree decl = *expr_p;
1479 /* ??? If this is a local variable, and it has not been seen in any
1480 outer BIND_EXPR, then it's probably the result of a duplicate
1481 declaration, for which we've already issued an error. It would
1482 be really nice if the front end wouldn't leak these at all.
1483 Currently the only known culprit is C++ destructors, as seen
1484 in g++.old-deja/g++.jason/binding.C. */
1485 if (TREE_CODE (decl) == VAR_DECL
1486 && !DECL_SEEN_IN_BIND_EXPR_P (decl)
1487 && !TREE_STATIC (decl) && !DECL_EXTERNAL (decl)
1488 && decl_function_context (decl) == current_function_decl)
1490 gcc_assert (errorcount || sorrycount);
1494 /* If the decl is an alias for another expression, substitute it now. */
1495 if (DECL_HAS_VALUE_EXPR_P (decl))
1497 *expr_p = unshare_expr (DECL_VALUE_EXPR (decl));
1505 /* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
1506 node pointed to by EXPR_P.
1509 : min_lval '[' val ']'
1511 | compound_lval '[' val ']'
1512 | compound_lval '.' ID
1514 This is not part of the original SIMPLE definition, which separates
1515 array and member references, but it seems reasonable to handle them
1516 together. Also, this way we don't run into problems with union
1517 aliasing; gcc requires that for accesses through a union to alias, the
1518 union reference must be explicit, which was not always the case when we
1519 were splitting up array and member refs.
1521 PRE_P points to the list where side effects that must happen before
1522 *EXPR_P should be stored.
1524 POST_P points to the list where side effects that must happen after
1525 *EXPR_P should be stored. */
1527 static enum gimplify_status
1528 gimplify_compound_lval (tree *expr_p, tree *pre_p,
1529 tree *post_p, fallback_t fallback)
1532 VEC(tree,heap) *stack;
1533 enum gimplify_status ret = GS_OK, tret;
1536 /* Create a stack of the subexpressions so later we can walk them in
1537 order from inner to outer. */
1538 stack = VEC_alloc (tree, heap, 10);
1540 /* We can handle anything that get_inner_reference can deal with. */
1541 for (p = expr_p; ; p = &TREE_OPERAND (*p, 0))
1544 /* Fold INDIRECT_REFs now to turn them into ARRAY_REFs. */
1545 if (TREE_CODE (*p) == INDIRECT_REF)
1546 *p = fold_indirect_ref (*p);
1548 if (handled_component_p (*p))
1550 /* Expand DECL_VALUE_EXPR now. In some cases that may expose
1551 additional COMPONENT_REFs. */
1552 else if ((TREE_CODE (*p) == VAR_DECL || TREE_CODE (*p) == PARM_DECL)
1553 && gimplify_var_or_parm_decl (p) == GS_OK)
1558 VEC_safe_push (tree, heap, stack, *p);
1561 gcc_assert (VEC_length (tree, stack));
1563 /* Now STACK is a stack of pointers to all the refs we've walked through
1564 and P points to the innermost expression.
1566 Java requires that we elaborated nodes in source order. That
1567 means we must gimplify the inner expression followed by each of
1568 the indices, in order. But we can't gimplify the inner
1569 expression until we deal with any variable bounds, sizes, or
1570 positions in order to deal with PLACEHOLDER_EXPRs.
1572 So we do this in three steps. First we deal with the annotations
1573 for any variables in the components, then we gimplify the base,
1574 then we gimplify any indices, from left to right. */
1575 for (i = VEC_length (tree, stack) - 1; i >= 0; i--)
1577 tree t = VEC_index (tree, stack, i);
1579 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1581 /* Gimplify the low bound and element type size and put them into
1582 the ARRAY_REF. If these values are set, they have already been
1584 if (!TREE_OPERAND (t, 2))
1586 tree low = unshare_expr (array_ref_low_bound (t));
1587 if (!is_gimple_min_invariant (low))
1589 TREE_OPERAND (t, 2) = low;
1590 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1591 is_gimple_formal_tmp_reg, fb_rvalue);
1592 ret = MIN (ret, tret);
1596 if (!TREE_OPERAND (t, 3))
1598 tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
1599 tree elmt_size = unshare_expr (array_ref_element_size (t));
1600 tree factor = size_int (TYPE_ALIGN_UNIT (elmt_type));
1602 /* Divide the element size by the alignment of the element
1604 elmt_size = size_binop (EXACT_DIV_EXPR, elmt_size, factor);
1606 if (!is_gimple_min_invariant (elmt_size))
1608 TREE_OPERAND (t, 3) = elmt_size;
1609 tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p,
1610 is_gimple_formal_tmp_reg, fb_rvalue);
1611 ret = MIN (ret, tret);
1615 else if (TREE_CODE (t) == COMPONENT_REF)
1617 /* Set the field offset into T and gimplify it. */
1618 if (!TREE_OPERAND (t, 2))
1620 tree offset = unshare_expr (component_ref_field_offset (t));
1621 tree field = TREE_OPERAND (t, 1);
1623 = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
1625 /* Divide the offset by its alignment. */
1626 offset = size_binop (EXACT_DIV_EXPR, offset, factor);
1628 if (!is_gimple_min_invariant (offset))
1630 TREE_OPERAND (t, 2) = offset;
1631 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1632 is_gimple_formal_tmp_reg, fb_rvalue);
1633 ret = MIN (ret, tret);
1639 /* Step 2 is to gimplify the base expression. Make sure lvalue is set
1640 so as to match the min_lval predicate. Failure to do so may result
1641 in the creation of large aggregate temporaries. */
1642 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval,
1643 fallback | fb_lvalue);
1644 ret = MIN (ret, tret);
1646 /* And finally, the indices and operands to BIT_FIELD_REF. During this
1647 loop we also remove any useless conversions. */
1648 for (; VEC_length (tree, stack) > 0; )
1650 tree t = VEC_pop (tree, stack);
1652 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1654 /* Gimplify the dimension.
1655 Temporary fix for gcc.c-torture/execute/20040313-1.c.
1656 Gimplify non-constant array indices into a temporary
1658 FIXME - The real fix is to gimplify post-modify
1659 expressions into a minimal gimple lvalue. However, that
1660 exposes bugs in alias analysis. The alias analyzer does
1661 not handle &PTR->FIELD very well. Will fix after the
1662 branch is merged into mainline (dnovillo 2004-05-03). */
1663 if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
1665 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1666 is_gimple_formal_tmp_reg, fb_rvalue);
1667 ret = MIN (ret, tret);
1670 else if (TREE_CODE (t) == BIT_FIELD_REF)
1672 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1673 is_gimple_val, fb_rvalue);
1674 ret = MIN (ret, tret);
1675 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1676 is_gimple_val, fb_rvalue);
1677 ret = MIN (ret, tret);
1680 STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0));
1682 /* The innermost expression P may have originally had TREE_SIDE_EFFECTS
1683 set which would have caused all the outer expressions in EXPR_P
1684 leading to P to also have had TREE_SIDE_EFFECTS set. */
1685 recalculate_side_effects (t);
1688 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1689 ret = MIN (ret, tret);
1691 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
1692 if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF)
1694 canonicalize_component_ref (expr_p);
1695 ret = MIN (ret, GS_OK);
1698 VEC_free (tree, heap, stack);
1703 /* Gimplify the self modifying expression pointed to by EXPR_P
1706 PRE_P points to the list where side effects that must happen before
1707 *EXPR_P should be stored.
1709 POST_P points to the list where side effects that must happen after
1710 *EXPR_P should be stored.
1712 WANT_VALUE is nonzero iff we want to use the value of this expression
1713 in another expression. */
1715 static enum gimplify_status
1716 gimplify_self_mod_expr (tree *expr_p, tree *pre_p, tree *post_p,
1719 enum tree_code code;
1720 tree lhs, lvalue, rhs, t1;
1722 enum tree_code arith_code;
1723 enum gimplify_status ret;
1725 code = TREE_CODE (*expr_p);
1727 gcc_assert (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR
1728 || code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR);
1730 /* Prefix or postfix? */
1731 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
1732 /* Faster to treat as prefix if result is not used. */
1733 postfix = want_value;
1737 /* Add or subtract? */
1738 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
1739 arith_code = PLUS_EXPR;
1741 arith_code = MINUS_EXPR;
1743 /* Gimplify the LHS into a GIMPLE lvalue. */
1744 lvalue = TREE_OPERAND (*expr_p, 0);
1745 ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
1746 if (ret == GS_ERROR)
1749 /* Extract the operands to the arithmetic operation. */
1751 rhs = TREE_OPERAND (*expr_p, 1);
1753 /* For postfix operator, we evaluate the LHS to an rvalue and then use
1754 that as the result value and in the postqueue operation. */
1757 ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
1758 if (ret == GS_ERROR)
1762 t1 = build (arith_code, TREE_TYPE (*expr_p), lhs, rhs);
1763 t1 = build (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
1767 gimplify_and_add (t1, post_p);
1778 /* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
1781 maybe_with_size_expr (tree *expr_p)
1783 tree expr = *expr_p;
1784 tree type = TREE_TYPE (expr);
1787 /* If we've already wrapped this or the type is error_mark_node, we can't do
1789 if (TREE_CODE (expr) == WITH_SIZE_EXPR
1790 || type == error_mark_node)
1793 /* If the size isn't known or is a constant, we have nothing to do. */
1794 size = TYPE_SIZE_UNIT (type);
1795 if (!size || TREE_CODE (size) == INTEGER_CST)
1798 /* Otherwise, make a WITH_SIZE_EXPR. */
1799 size = unshare_expr (size);
1800 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr);
1801 *expr_p = build2 (WITH_SIZE_EXPR, type, expr, size);
1804 /* Subroutine of gimplify_call_expr: Gimplify a single argument. */
1806 static enum gimplify_status
1807 gimplify_arg (tree *expr_p, tree *pre_p)
1809 bool (*test) (tree);
1812 /* In general, we allow lvalues for function arguments to avoid
1813 extra overhead of copying large aggregates out of even larger
1814 aggregates into temporaries only to copy the temporaries to
1815 the argument list. Make optimizers happy by pulling out to
1816 temporaries those types that fit in registers. */
1817 if (is_gimple_reg_type (TREE_TYPE (*expr_p)))
1818 test = is_gimple_val, fb = fb_rvalue;
1820 test = is_gimple_lvalue, fb = fb_either;
1822 /* If this is a variable sized type, we must remember the size. */
1823 maybe_with_size_expr (expr_p);
1825 /* There is a sequence point before a function call. Side effects in
1826 the argument list must occur before the actual call. So, when
1827 gimplifying arguments, force gimplify_expr to use an internal
1828 post queue which is then appended to the end of PRE_P. */
1829 return gimplify_expr (expr_p, pre_p, NULL, test, fb);
1832 /* Gimplify the CALL_EXPR node pointed to by EXPR_P. PRE_P points to the
1833 list where side effects that must happen before *EXPR_P should be stored.
1834 WANT_VALUE is true if the result of the call is desired. */
1836 static enum gimplify_status
1837 gimplify_call_expr (tree *expr_p, tree *pre_p, bool want_value)
1841 enum gimplify_status ret;
1843 gcc_assert (TREE_CODE (*expr_p) == CALL_EXPR);
1845 /* For reliable diagnostics during inlining, it is necessary that
1846 every call_expr be annotated with file and line. */
1847 if (! EXPR_HAS_LOCATION (*expr_p))
1848 SET_EXPR_LOCATION (*expr_p, input_location);
1850 /* This may be a call to a builtin function.
1852 Builtin function calls may be transformed into different
1853 (and more efficient) builtin function calls under certain
1854 circumstances. Unfortunately, gimplification can muck things
1855 up enough that the builtin expanders are not aware that certain
1856 transformations are still valid.
1858 So we attempt transformation/gimplification of the call before
1859 we gimplify the CALL_EXPR. At this time we do not manage to
1860 transform all calls in the same manner as the expanders do, but
1861 we do transform most of them. */
1862 decl = get_callee_fndecl (*expr_p);
1863 if (decl && DECL_BUILT_IN (decl))
1865 tree arglist = TREE_OPERAND (*expr_p, 1);
1866 tree new = fold_builtin (decl, arglist, !want_value);
1868 if (new && new != *expr_p)
1870 /* There was a transformation of this call which computes the
1871 same value, but in a more efficient way. Return and try
1877 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
1878 && DECL_FUNCTION_CODE (decl) == BUILT_IN_VA_START)
1880 if (!arglist || !TREE_CHAIN (arglist))
1882 error ("too few arguments to function %<va_start%>");
1883 *expr_p = build_empty_stmt ();
1887 if (fold_builtin_next_arg (TREE_CHAIN (arglist)))
1889 *expr_p = build_empty_stmt ();
1892 /* Avoid gimplifying the second argument to va_start, which needs
1893 to be the plain PARM_DECL. */
1894 return gimplify_arg (&TREE_VALUE (TREE_OPERAND (*expr_p, 1)), pre_p);
1898 /* There is a sequence point before the call, so any side effects in
1899 the calling expression must occur before the actual call. Force
1900 gimplify_expr to use an internal post queue. */
1901 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, NULL,
1902 is_gimple_call_addr, fb_rvalue);
1904 if (PUSH_ARGS_REVERSED)
1905 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1906 for (arglist = TREE_OPERAND (*expr_p, 1); arglist;
1907 arglist = TREE_CHAIN (arglist))
1909 enum gimplify_status t;
1911 t = gimplify_arg (&TREE_VALUE (arglist), pre_p);
1916 if (PUSH_ARGS_REVERSED)
1917 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1919 /* Try this again in case gimplification exposed something. */
1920 if (ret != GS_ERROR)
1922 decl = get_callee_fndecl (*expr_p);
1923 if (decl && DECL_BUILT_IN (decl))
1925 tree arglist = TREE_OPERAND (*expr_p, 1);
1926 tree new = fold_builtin (decl, arglist, !want_value);
1928 if (new && new != *expr_p)
1930 /* There was a transformation of this call which computes the
1931 same value, but in a more efficient way. Return and try
1939 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
1940 decl. This allows us to eliminate redundant or useless
1941 calls to "const" functions. */
1942 if (TREE_CODE (*expr_p) == CALL_EXPR
1943 && (call_expr_flags (*expr_p) & (ECF_CONST | ECF_PURE)))
1944 TREE_SIDE_EFFECTS (*expr_p) = 0;
1949 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
1950 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
1952 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
1953 condition is true or false, respectively. If null, we should generate
1954 our own to skip over the evaluation of this specific expression.
1956 This function is the tree equivalent of do_jump.
1958 shortcut_cond_r should only be called by shortcut_cond_expr. */
1961 shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p)
1963 tree local_label = NULL_TREE;
1964 tree t, expr = NULL;
1966 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
1967 retain the shortcut semantics. Just insert the gotos here;
1968 shortcut_cond_expr will append the real blocks later. */
1969 if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
1971 /* Turn if (a && b) into
1973 if (a); else goto no;
1974 if (b) goto yes; else goto no;
1977 if (false_label_p == NULL)
1978 false_label_p = &local_label;
1980 t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p);
1981 append_to_statement_list (t, &expr);
1983 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1985 append_to_statement_list (t, &expr);
1987 else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
1989 /* Turn if (a || b) into
1992 if (b) goto yes; else goto no;
1995 if (true_label_p == NULL)
1996 true_label_p = &local_label;
1998 t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL);
1999 append_to_statement_list (t, &expr);
2001 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2003 append_to_statement_list (t, &expr);
2005 else if (TREE_CODE (pred) == COND_EXPR)
2007 /* As long as we're messing with gotos, turn if (a ? b : c) into
2009 if (b) goto yes; else goto no;
2011 if (c) goto yes; else goto no; */
2012 expr = build (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
2013 shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2015 shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
2020 expr = build (COND_EXPR, void_type_node, pred,
2021 build_and_jump (true_label_p),
2022 build_and_jump (false_label_p));
2027 t = build1 (LABEL_EXPR, void_type_node, local_label);
2028 append_to_statement_list (t, &expr);
2035 shortcut_cond_expr (tree expr)
2037 tree pred = TREE_OPERAND (expr, 0);
2038 tree then_ = TREE_OPERAND (expr, 1);
2039 tree else_ = TREE_OPERAND (expr, 2);
2040 tree true_label, false_label, end_label, t;
2042 tree *false_label_p;
2043 bool emit_end, emit_false, jump_over_else;
2044 bool then_se = then_ && TREE_SIDE_EFFECTS (then_);
2045 bool else_se = else_ && TREE_SIDE_EFFECTS (else_);
2047 /* First do simple transformations. */
2050 /* If there is no 'else', turn (a && b) into if (a) if (b). */
2051 while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2053 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2054 then_ = shortcut_cond_expr (expr);
2055 then_se = then_ && TREE_SIDE_EFFECTS (then_);
2056 pred = TREE_OPERAND (pred, 0);
2057 expr = build (COND_EXPR, void_type_node, pred, then_, NULL_TREE);
2062 /* If there is no 'then', turn
2065 if (a); else if (b); else d. */
2066 while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2068 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2069 else_ = shortcut_cond_expr (expr);
2070 else_se = else_ && TREE_SIDE_EFFECTS (else_);
2071 pred = TREE_OPERAND (pred, 0);
2072 expr = build (COND_EXPR, void_type_node, pred, NULL_TREE, else_);
2076 /* If we're done, great. */
2077 if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
2078 && TREE_CODE (pred) != TRUTH_ORIF_EXPR)
2081 /* Otherwise we need to mess with gotos. Change
2084 if (a); else goto no;
2087 and recursively gimplify the condition. */
2089 true_label = false_label = end_label = NULL_TREE;
2091 /* If our arms just jump somewhere, hijack those labels so we don't
2092 generate jumps to jumps. */
2095 && TREE_CODE (then_) == GOTO_EXPR
2096 && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
2098 true_label = GOTO_DESTINATION (then_);
2104 && TREE_CODE (else_) == GOTO_EXPR
2105 && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
2107 false_label = GOTO_DESTINATION (else_);
2112 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2114 true_label_p = &true_label;
2116 true_label_p = NULL;
2118 /* The 'else' branch also needs a label if it contains interesting code. */
2119 if (false_label || else_se)
2120 false_label_p = &false_label;
2122 false_label_p = NULL;
2124 /* If there was nothing else in our arms, just forward the label(s). */
2125 if (!then_se && !else_se)
2126 return shortcut_cond_r (pred, true_label_p, false_label_p);
2128 /* If our last subexpression already has a terminal label, reuse it. */
2130 expr = expr_last (else_);
2132 expr = expr_last (then_);
2135 if (expr && TREE_CODE (expr) == LABEL_EXPR)
2136 end_label = LABEL_EXPR_LABEL (expr);
2138 /* If we don't care about jumping to the 'else' branch, jump to the end
2139 if the condition is false. */
2141 false_label_p = &end_label;
2143 /* We only want to emit these labels if we aren't hijacking them. */
2144 emit_end = (end_label == NULL_TREE);
2145 emit_false = (false_label == NULL_TREE);
2147 /* We only emit the jump over the else clause if we have to--if the
2148 then clause may fall through. Otherwise we can wind up with a
2149 useless jump and a useless label at the end of gimplified code,
2150 which will cause us to think that this conditional as a whole
2151 falls through even if it doesn't. If we then inline a function
2152 which ends with such a condition, that can cause us to issue an
2153 inappropriate warning about control reaching the end of a
2154 non-void function. */
2155 jump_over_else = block_may_fallthru (then_);
2157 pred = shortcut_cond_r (pred, true_label_p, false_label_p);
2160 append_to_statement_list (pred, &expr);
2162 append_to_statement_list (then_, &expr);
2167 t = build_and_jump (&end_label);
2168 append_to_statement_list (t, &expr);
2172 t = build1 (LABEL_EXPR, void_type_node, false_label);
2173 append_to_statement_list (t, &expr);
2175 append_to_statement_list (else_, &expr);
2177 if (emit_end && end_label)
2179 t = build1 (LABEL_EXPR, void_type_node, end_label);
2180 append_to_statement_list (t, &expr);
2186 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2189 gimple_boolify (tree expr)
2191 tree type = TREE_TYPE (expr);
2193 if (TREE_CODE (type) == BOOLEAN_TYPE)
2196 switch (TREE_CODE (expr))
2198 case TRUTH_AND_EXPR:
2200 case TRUTH_XOR_EXPR:
2201 case TRUTH_ANDIF_EXPR:
2202 case TRUTH_ORIF_EXPR:
2203 /* Also boolify the arguments of truth exprs. */
2204 TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
2207 case TRUTH_NOT_EXPR:
2208 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2211 case EQ_EXPR: case NE_EXPR:
2212 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2213 /* These expressions always produce boolean results. */
2214 TREE_TYPE (expr) = boolean_type_node;
2218 /* Other expressions that get here must have boolean values, but
2219 might need to be converted to the appropriate mode. */
2220 return convert (boolean_type_node, expr);
2224 /* Convert the conditional expression pointed to by EXPR_P '(p) ? a : b;'
2233 The second form is used when *EXPR_P is of type void.
2235 TARGET is the tree for T1 above.
2237 PRE_P points to the list where side effects that must happen before
2238 *EXPR_P should be stored. */
2240 static enum gimplify_status
2241 gimplify_cond_expr (tree *expr_p, tree *pre_p, fallback_t fallback)
2243 tree expr = *expr_p;
2244 tree tmp, tmp2, type;
2245 enum gimplify_status ret;
2247 type = TREE_TYPE (expr);
2249 /* If this COND_EXPR has a value, copy the values into a temporary within
2251 if (! VOID_TYPE_P (type))
2255 if ((fallback & fb_lvalue) == 0)
2257 result = tmp2 = tmp = create_tmp_var (TREE_TYPE (expr), "iftmp");
2262 tree type = build_pointer_type (TREE_TYPE (expr));
2264 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2265 TREE_OPERAND (expr, 1) =
2266 build_fold_addr_expr (TREE_OPERAND (expr, 1));
2268 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2269 TREE_OPERAND (expr, 2) =
2270 build_fold_addr_expr (TREE_OPERAND (expr, 2));
2272 tmp2 = tmp = create_tmp_var (type, "iftmp");
2274 expr = build (COND_EXPR, void_type_node, TREE_OPERAND (expr, 0),
2275 TREE_OPERAND (expr, 1), TREE_OPERAND (expr, 2));
2277 result = build_fold_indirect_ref (tmp);
2281 /* Build the then clause, 't1 = a;'. But don't build an assignment
2282 if this branch is void; in C++ it can be, if it's a throw. */
2283 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2284 TREE_OPERAND (expr, 1)
2285 = build (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 1));
2287 /* Build the else clause, 't1 = b;'. */
2288 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2289 TREE_OPERAND (expr, 2)
2290 = build (MODIFY_EXPR, void_type_node, tmp2, TREE_OPERAND (expr, 2));
2292 TREE_TYPE (expr) = void_type_node;
2293 recalculate_side_effects (expr);
2295 /* Move the COND_EXPR to the prequeue. */
2296 gimplify_and_add (expr, pre_p);
2302 /* Make sure the condition has BOOLEAN_TYPE. */
2303 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2305 /* Break apart && and || conditions. */
2306 if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
2307 || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
2309 expr = shortcut_cond_expr (expr);
2311 if (expr != *expr_p)
2315 /* We can't rely on gimplify_expr to re-gimplify the expanded
2316 form properly, as cleanups might cause the target labels to be
2317 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2318 set up a conditional context. */
2319 gimple_push_condition ();
2320 gimplify_stmt (expr_p);
2321 gimple_pop_condition (pre_p);
2327 /* Now do the normal gimplification. */
2328 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2329 is_gimple_condexpr, fb_rvalue);
2331 gimple_push_condition ();
2333 gimplify_to_stmt_list (&TREE_OPERAND (expr, 1));
2334 gimplify_to_stmt_list (&TREE_OPERAND (expr, 2));
2335 recalculate_side_effects (expr);
2337 gimple_pop_condition (pre_p);
2339 if (ret == GS_ERROR)
2341 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2343 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 2)))
2344 /* Rewrite "if (a); else b" to "if (!a) b" */
2346 TREE_OPERAND (expr, 0) = invert_truthvalue (TREE_OPERAND (expr, 0));
2347 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2348 is_gimple_condexpr, fb_rvalue);
2350 tmp = TREE_OPERAND (expr, 1);
2351 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 2);
2352 TREE_OPERAND (expr, 2) = tmp;
2355 /* Both arms are empty; replace the COND_EXPR with its predicate. */
2356 expr = TREE_OPERAND (expr, 0);
2362 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2363 a call to __builtin_memcpy. */
2365 static enum gimplify_status
2366 gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value)
2368 tree args, t, to, to_ptr, from;
2370 to = TREE_OPERAND (*expr_p, 0);
2371 from = TREE_OPERAND (*expr_p, 1);
2373 args = tree_cons (NULL, size, NULL);
2375 t = build_fold_addr_expr (from);
2376 args = tree_cons (NULL, t, args);
2378 to_ptr = build_fold_addr_expr (to);
2379 args = tree_cons (NULL, to_ptr, args);
2380 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
2381 t = build_function_call_expr (t, args);
2385 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2386 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2393 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2394 a call to __builtin_memset. In this case we know that the RHS is
2395 a CONSTRUCTOR with an empty element list. */
2397 static enum gimplify_status
2398 gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value)
2400 tree args, t, to, to_ptr;
2402 to = TREE_OPERAND (*expr_p, 0);
2404 args = tree_cons (NULL, size, NULL);
2406 args = tree_cons (NULL, integer_zero_node, args);
2408 to_ptr = build_fold_addr_expr (to);
2409 args = tree_cons (NULL, to_ptr, args);
2410 t = implicit_built_in_decls[BUILT_IN_MEMSET];
2411 t = build_function_call_expr (t, args);
2415 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2416 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2423 /* A subroutine of gimplify_init_ctor_preeval. Called via walk_tree,
2424 determine, cautiously, if a CONSTRUCTOR overlaps the lhs of an
2425 assignment. Returns non-null if we detect a potential overlap. */
2427 struct gimplify_init_ctor_preeval_data
2429 /* The base decl of the lhs object. May be NULL, in which case we
2430 have to assume the lhs is indirect. */
2433 /* The alias set of the lhs object. */
2438 gimplify_init_ctor_preeval_1 (tree *tp, int *walk_subtrees, void *xdata)
2440 struct gimplify_init_ctor_preeval_data *data
2441 = (struct gimplify_init_ctor_preeval_data *) xdata;
2444 /* If we find the base object, obviously we have overlap. */
2445 if (data->lhs_base_decl == t)
2448 /* If the constructor component is indirect, determine if we have a
2449 potential overlap with the lhs. The only bits of information we
2450 have to go on at this point are addressability and alias sets. */
2451 if (TREE_CODE (t) == INDIRECT_REF
2452 && (!data->lhs_base_decl || TREE_ADDRESSABLE (data->lhs_base_decl))
2453 && alias_sets_conflict_p (data->lhs_alias_set, get_alias_set (t)))
2456 if (IS_TYPE_OR_DECL_P (t))
2461 /* A subroutine of gimplify_init_constructor. Pre-evaluate *EXPR_P,
2462 force values that overlap with the lhs (as described by *DATA)
2463 into temporaries. */
2466 gimplify_init_ctor_preeval (tree *expr_p, tree *pre_p, tree *post_p,
2467 struct gimplify_init_ctor_preeval_data *data)
2469 enum gimplify_status one;
2471 /* If the value is invariant, then there's nothing to pre-evaluate.
2472 But ensure it doesn't have any side-effects since a SAVE_EXPR is
2473 invariant but has side effects and might contain a reference to
2474 the object we're initializing. */
2475 if (TREE_INVARIANT (*expr_p) && !TREE_SIDE_EFFECTS (*expr_p))
2478 /* If the type has non-trivial constructors, we can't pre-evaluate. */
2479 if (TREE_ADDRESSABLE (TREE_TYPE (*expr_p)))
2482 /* Recurse for nested constructors. */
2483 if (TREE_CODE (*expr_p) == CONSTRUCTOR)
2485 unsigned HOST_WIDE_INT ix;
2486 constructor_elt *ce;
2487 VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (*expr_p);
2489 for (ix = 0; VEC_iterate (constructor_elt, v, ix, ce); ix++)
2490 gimplify_init_ctor_preeval (&ce->value, pre_p, post_p, data);
2494 /* We can't preevaluate if the type contains a placeholder. */
2495 if (type_contains_placeholder_p (TREE_TYPE (*expr_p)))
2498 /* Gimplify the constructor element to something appropriate for the rhs
2499 of a MODIFY_EXPR. Given that we know the lhs is an aggregate, we know
2500 the gimplifier will consider this a store to memory. Doing this
2501 gimplification now means that we won't have to deal with complicated
2502 language-specific trees, nor trees like SAVE_EXPR that can induce
2503 exponential search behavior. */
2504 one = gimplify_expr (expr_p, pre_p, post_p, is_gimple_mem_rhs, fb_rvalue);
2505 if (one == GS_ERROR)
2511 /* If we gimplified to a bare decl, we can be sure that it doesn't overlap
2512 with the lhs, since "a = { .x=a }" doesn't make sense. This will
2513 always be true for all scalars, since is_gimple_mem_rhs insists on a
2514 temporary variable for them. */
2515 if (DECL_P (*expr_p))
2518 /* If this is of variable size, we have no choice but to assume it doesn't
2519 overlap since we can't make a temporary for it. */
2520 if (!TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (*expr_p))))
2523 /* Otherwise, we must search for overlap ... */
2524 if (!walk_tree (expr_p, gimplify_init_ctor_preeval_1, data, NULL))
2527 /* ... and if found, force the value into a temporary. */
2528 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
2531 /* A subroutine of gimplify_init_ctor_eval. Create a loop for
2532 a RANGE_EXPR in a CONSTRUCTOR for an array.
2536 object[var] = value;
2543 We increment var _after_ the loop exit check because we might otherwise
2544 fail if upper == TYPE_MAX_VALUE (type for upper).
2546 Note that we never have to deal with SAVE_EXPRs here, because this has
2547 already been taken care of for us, in gimplify_init_ctor_preeval(). */
2549 static void gimplify_init_ctor_eval (tree, VEC(constructor_elt,gc) *,
2553 gimplify_init_ctor_eval_range (tree object, tree lower, tree upper,
2554 tree value, tree array_elt_type,
2555 tree *pre_p, bool cleared)
2557 tree loop_entry_label, loop_exit_label;
2558 tree var, var_type, cref;
2560 loop_entry_label = create_artificial_label ();
2561 loop_exit_label = create_artificial_label ();
2563 /* Create and initialize the index variable. */
2564 var_type = TREE_TYPE (upper);
2565 var = create_tmp_var (var_type, NULL);
2566 append_to_statement_list (build2 (MODIFY_EXPR, var_type, var, lower), pre_p);
2568 /* Add the loop entry label. */
2569 append_to_statement_list (build1 (LABEL_EXPR,
2574 /* Build the reference. */
2575 cref = build4 (ARRAY_REF, array_elt_type, unshare_expr (object),
2576 var, NULL_TREE, NULL_TREE);
2578 /* If we are a constructor, just call gimplify_init_ctor_eval to do
2579 the store. Otherwise just assign value to the reference. */
2581 if (TREE_CODE (value) == CONSTRUCTOR)
2582 /* NB we might have to call ourself recursively through
2583 gimplify_init_ctor_eval if the value is a constructor. */
2584 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
2587 append_to_statement_list (build2 (MODIFY_EXPR, TREE_TYPE (cref),
2591 /* We exit the loop when the index var is equal to the upper bound. */
2592 gimplify_and_add (build3 (COND_EXPR, void_type_node,
2593 build2 (EQ_EXPR, boolean_type_node,
2601 /* Otherwise, increment the index var... */
2602 append_to_statement_list (build2 (MODIFY_EXPR, var_type, var,
2603 build2 (PLUS_EXPR, var_type, var,
2604 fold_convert (var_type,
2605 integer_one_node))),
2608 /* ...and jump back to the loop entry. */
2609 append_to_statement_list (build1 (GOTO_EXPR,
2614 /* Add the loop exit label. */
2615 append_to_statement_list (build1 (LABEL_EXPR,
2621 /* Return true if FDECL is accessing a field that is zero sized. */
2624 zero_sized_field_decl (tree fdecl)
2626 if (TREE_CODE (fdecl) == FIELD_DECL && DECL_SIZE (fdecl)
2627 && integer_zerop (DECL_SIZE (fdecl)))
2632 /* Return true if TYPE is zero sized. */
2635 zero_sized_type (tree type)
2637 if (AGGREGATE_TYPE_P (type) && TYPE_SIZE (type)
2638 && integer_zerop (TYPE_SIZE (type)))
2643 /* A subroutine of gimplify_init_constructor. Generate individual
2644 MODIFY_EXPRs for a CONSTRUCTOR. OBJECT is the LHS against which the
2645 assignments should happen. ELTS is the CONSTRUCTOR_ELTS of the
2646 CONSTRUCTOR. CLEARED is true if the entire LHS object has been
2650 gimplify_init_ctor_eval (tree object, VEC(constructor_elt,gc) *elts,
2651 tree *pre_p, bool cleared)
2653 tree array_elt_type = NULL;
2654 unsigned HOST_WIDE_INT ix;
2655 tree purpose, value;
2657 if (TREE_CODE (TREE_TYPE (object)) == ARRAY_TYPE)
2658 array_elt_type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object)));
2660 FOR_EACH_CONSTRUCTOR_ELT (elts, ix, purpose, value)
2664 /* NULL values are created above for gimplification errors. */
2668 if (cleared && initializer_zerop (value))
2671 /* ??? Here's to hoping the front end fills in all of the indices,
2672 so we don't have to figure out what's missing ourselves. */
2673 gcc_assert (purpose);
2675 /* Skip zero-sized fields, unless value has side-effects. This can
2676 happen with calls to functions returning a zero-sized type, which
2677 we shouldn't discard. As a number of downstream passes don't
2678 expect sets of zero-sized fields, we rely on the gimplification of
2679 the MODIFY_EXPR we make below to drop the assignment statement. */
2680 if (! TREE_SIDE_EFFECTS (value) && zero_sized_field_decl (purpose))
2683 /* If we have a RANGE_EXPR, we have to build a loop to assign the
2685 if (TREE_CODE (purpose) == RANGE_EXPR)
2687 tree lower = TREE_OPERAND (purpose, 0);
2688 tree upper = TREE_OPERAND (purpose, 1);
2690 /* If the lower bound is equal to upper, just treat it as if
2691 upper was the index. */
2692 if (simple_cst_equal (lower, upper))
2696 gimplify_init_ctor_eval_range (object, lower, upper, value,
2697 array_elt_type, pre_p, cleared);
2704 cref = build (ARRAY_REF, array_elt_type, unshare_expr (object),
2705 purpose, NULL_TREE, NULL_TREE);
2709 gcc_assert (TREE_CODE (purpose) == FIELD_DECL);
2710 cref = build (COMPONENT_REF, TREE_TYPE (purpose),
2711 unshare_expr (object), purpose, NULL_TREE);
2714 if (TREE_CODE (value) == CONSTRUCTOR
2715 && TREE_CODE (TREE_TYPE (value)) != VECTOR_TYPE)
2716 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
2720 init = build2 (INIT_EXPR, TREE_TYPE (cref), cref, value);
2721 gimplify_and_add (init, pre_p);
2726 /* A subroutine of gimplify_modify_expr. Break out elements of a
2727 CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.
2729 Note that we still need to clear any elements that don't have explicit
2730 initializers, so if not all elements are initialized we keep the
2731 original MODIFY_EXPR, we just remove all of the constructor elements. */
2733 static enum gimplify_status
2734 gimplify_init_constructor (tree *expr_p, tree *pre_p,
2735 tree *post_p, bool want_value)
2738 tree ctor = TREE_OPERAND (*expr_p, 1);
2739 tree type = TREE_TYPE (ctor);
2740 enum gimplify_status ret;
2741 VEC(constructor_elt,gc) *elts;
2743 if (TREE_CODE (ctor) != CONSTRUCTOR)
2744 return GS_UNHANDLED;
2746 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
2747 is_gimple_lvalue, fb_lvalue);
2748 if (ret == GS_ERROR)
2750 object = TREE_OPERAND (*expr_p, 0);
2752 elts = CONSTRUCTOR_ELTS (ctor);
2755 switch (TREE_CODE (type))
2759 case QUAL_UNION_TYPE:
2762 struct gimplify_init_ctor_preeval_data preeval_data;
2763 HOST_WIDE_INT num_type_elements, num_ctor_elements;
2764 HOST_WIDE_INT num_nonzero_elements, num_nonconstant_elements;
2767 /* Aggregate types must lower constructors to initialization of
2768 individual elements. The exception is that a CONSTRUCTOR node
2769 with no elements indicates zero-initialization of the whole. */
2770 if (VEC_empty (constructor_elt, elts))
2773 categorize_ctor_elements (ctor, &num_nonzero_elements,
2774 &num_nonconstant_elements,
2775 &num_ctor_elements, &cleared);
2777 /* If a const aggregate variable is being initialized, then it
2778 should never be a lose to promote the variable to be static. */
2779 if (num_nonconstant_elements == 0
2780 && num_nonzero_elements > 1
2781 && TREE_READONLY (object)
2782 && TREE_CODE (object) == VAR_DECL)
2784 DECL_INITIAL (object) = ctor;
2785 TREE_STATIC (object) = 1;
2786 if (!DECL_NAME (object))
2787 DECL_NAME (object) = create_tmp_var_name ("C");
2788 walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL);
2790 /* ??? C++ doesn't automatically append a .<number> to the
2791 assembler name, and even when it does, it looks a FE private
2792 data structures to figure out what that number should be,
2793 which are not set for this variable. I suppose this is
2794 important for local statics for inline functions, which aren't
2795 "local" in the object file sense. So in order to get a unique
2796 TU-local symbol, we must invoke the lhd version now. */
2797 lhd_set_decl_assembler_name (object);
2799 *expr_p = NULL_TREE;
2803 /* If there are "lots" of initialized elements, even discounting
2804 those that are not address constants (and thus *must* be
2805 computed at runtime), then partition the constructor into
2806 constant and non-constant parts. Block copy the constant
2807 parts in, then generate code for the non-constant parts. */
2808 /* TODO. There's code in cp/typeck.c to do this. */
2810 num_type_elements = count_type_elements (type, true);
2812 /* If count_type_elements could not determine number of type elements
2813 for a constant-sized object, assume clearing is needed.
2814 Don't do this for variable-sized objects, as store_constructor
2815 will ignore the clearing of variable-sized objects. */
2816 if (num_type_elements < 0 && int_size_in_bytes (type) >= 0)
2818 /* If there are "lots" of zeros, then block clear the object first. */
2819 else if (num_type_elements - num_nonzero_elements > CLEAR_RATIO
2820 && num_nonzero_elements < num_type_elements/4)
2822 /* ??? This bit ought not be needed. For any element not present
2823 in the initializer, we should simply set them to zero. Except
2824 we'd need to *find* the elements that are not present, and that
2825 requires trickery to avoid quadratic compile-time behavior in
2826 large cases or excessive memory use in small cases. */
2827 else if (num_ctor_elements < num_type_elements)
2830 /* If there are "lots" of initialized elements, and all of them
2831 are valid address constants, then the entire initializer can
2832 be dropped to memory, and then memcpy'd out. Don't do this
2833 for sparse arrays, though, as it's more efficient to follow
2834 the standard CONSTRUCTOR behavior of memset followed by
2835 individual element initialization. */
2836 if (num_nonconstant_elements == 0 && !cleared)
2838 HOST_WIDE_INT size = int_size_in_bytes (type);
2841 /* ??? We can still get unbounded array types, at least
2842 from the C++ front end. This seems wrong, but attempt
2843 to work around it for now. */
2846 size = int_size_in_bytes (TREE_TYPE (object));
2848 TREE_TYPE (ctor) = type = TREE_TYPE (object);
2851 /* Find the maximum alignment we can assume for the object. */
2852 /* ??? Make use of DECL_OFFSET_ALIGN. */
2853 if (DECL_P (object))
2854 align = DECL_ALIGN (object);
2856 align = TYPE_ALIGN (type);
2858 if (size > 0 && !can_move_by_pieces (size, align))
2860 tree new = create_tmp_var_raw (type, "C");
2862 gimple_add_tmp_var (new);
2863 TREE_STATIC (new) = 1;
2864 TREE_READONLY (new) = 1;
2865 DECL_INITIAL (new) = ctor;
2866 if (align > DECL_ALIGN (new))
2868 DECL_ALIGN (new) = align;
2869 DECL_USER_ALIGN (new) = 1;
2871 walk_tree (&DECL_INITIAL (new), force_labels_r, NULL, NULL);
2873 TREE_OPERAND (*expr_p, 1) = new;
2875 /* This is no longer an assignment of a CONSTRUCTOR, but
2876 we still may have processing to do on the LHS. So
2877 pretend we didn't do anything here to let that happen. */
2878 return GS_UNHANDLED;
2884 /* Zap the CONSTRUCTOR element list, which simplifies this case.
2885 Note that we still have to gimplify, in order to handle the
2886 case of variable sized types. Avoid shared tree structures. */
2887 CONSTRUCTOR_ELTS (ctor) = NULL;
2888 object = unshare_expr (object);
2889 gimplify_stmt (expr_p);
2890 append_to_statement_list (*expr_p, pre_p);
2893 /* If we have not block cleared the object, or if there are nonzero
2894 elements in the constructor, add assignments to the individual
2895 scalar fields of the object. */
2896 if (!cleared || num_nonzero_elements > 0)
2898 preeval_data.lhs_base_decl = get_base_address (object);
2899 if (!DECL_P (preeval_data.lhs_base_decl))
2900 preeval_data.lhs_base_decl = NULL;
2901 preeval_data.lhs_alias_set = get_alias_set (object);
2903 gimplify_init_ctor_preeval (&TREE_OPERAND (*expr_p, 1),
2904 pre_p, post_p, &preeval_data);
2905 gimplify_init_ctor_eval (object, elts, pre_p, cleared);
2908 *expr_p = NULL_TREE;
2916 /* Extract the real and imaginary parts out of the ctor. */
2917 gcc_assert (VEC_length (constructor_elt, elts) == 2);
2918 r = VEC_index (constructor_elt, elts, 0)->value;
2919 i = VEC_index (constructor_elt, elts, 1)->value;
2920 if (r == NULL || i == NULL)
2922 tree zero = convert (TREE_TYPE (type), integer_zero_node);
2929 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
2930 represent creation of a complex value. */
2931 if (TREE_CONSTANT (r) && TREE_CONSTANT (i))
2933 ctor = build_complex (type, r, i);
2934 TREE_OPERAND (*expr_p, 1) = ctor;
2938 ctor = build (COMPLEX_EXPR, type, r, i);
2939 TREE_OPERAND (*expr_p, 1) = ctor;
2940 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
2941 rhs_predicate_for (TREE_OPERAND (*expr_p, 0)),
2949 unsigned HOST_WIDE_INT ix;
2950 constructor_elt *ce;
2952 /* Go ahead and simplify constant constructors to VECTOR_CST. */
2953 if (TREE_CONSTANT (ctor))
2955 bool constant_p = true;
2958 /* Even when ctor is constant, it might contain non-*_CST
2959 elements (e.g. { 1.0/0.0 - 1.0/0.0, 0.0 }) and those don't
2960 belong into VECTOR_CST nodes. */
2961 FOR_EACH_CONSTRUCTOR_VALUE (elts, ix, value)
2962 if (!CONSTANT_CLASS_P (value))
2970 TREE_OPERAND (*expr_p, 1) = build_vector_from_ctor (type, elts);
2975 /* Vector types use CONSTRUCTOR all the way through gimple
2976 compilation as a general initializer. */
2977 for (ix = 0; VEC_iterate (constructor_elt, elts, ix, ce); ix++)
2979 enum gimplify_status tret;
2980 tret = gimplify_expr (&ce->value, pre_p, post_p,
2981 is_gimple_val, fb_rvalue);
2982 if (tret == GS_ERROR)
2989 /* So how did we get a CONSTRUCTOR for a scalar type? */
2993 if (ret == GS_ERROR)
2995 else if (want_value)
2997 append_to_statement_list (*expr_p, pre_p);
3005 /* Given a pointer value OP0, return a simplified version of an
3006 indirection through OP0, or NULL_TREE if no simplification is
3007 possible. This may only be applied to a rhs of an expression.
3008 Note that the resulting type may be different from the type pointed
3009 to in the sense that it is still compatible from the langhooks
3013 fold_indirect_ref_rhs (tree t)
3015 tree type = TREE_TYPE (TREE_TYPE (t));
3020 subtype = TREE_TYPE (sub);
3021 if (!POINTER_TYPE_P (subtype))
3024 if (TREE_CODE (sub) == ADDR_EXPR)
3026 tree op = TREE_OPERAND (sub, 0);
3027 tree optype = TREE_TYPE (op);
3029 if (lang_hooks.types_compatible_p (type, optype))
3031 /* *(foo *)&fooarray => fooarray[0] */
3032 else if (TREE_CODE (optype) == ARRAY_TYPE
3033 && lang_hooks.types_compatible_p (type, TREE_TYPE (optype)))
3035 tree type_domain = TYPE_DOMAIN (optype);
3036 tree min_val = size_zero_node;
3037 if (type_domain && TYPE_MIN_VALUE (type_domain))
3038 min_val = TYPE_MIN_VALUE (type_domain);
3039 return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
3043 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
3044 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
3045 && lang_hooks.types_compatible_p (type, TREE_TYPE (TREE_TYPE (subtype))))
3048 tree min_val = size_zero_node;
3050 sub = fold_indirect_ref_rhs (sub);
3052 sub = build1 (INDIRECT_REF, TREE_TYPE (subtype), osub);
3053 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
3054 if (type_domain && TYPE_MIN_VALUE (type_domain))
3055 min_val = TYPE_MIN_VALUE (type_domain);
3056 return build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
3062 /* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs
3063 based on the code of the RHS. We loop for as long as something changes. */
3065 static enum gimplify_status
3066 gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p,
3067 tree *post_p, bool want_value)
3069 enum gimplify_status ret = GS_OK;
3071 while (ret != GS_UNHANDLED)
3072 switch (TREE_CODE (*from_p))
3076 /* If we have code like
3080 where the type of "x" is a (possibly cv-qualified variant
3081 of "A"), treat the entire expression as identical to "x".
3082 This kind of code arises in C++ when an object is bound
3083 to a const reference, and if "x" is a TARGET_EXPR we want
3084 to take advantage of the optimization below. */
3085 tree t = fold_indirect_ref_rhs (TREE_OPERAND (*from_p, 0));
3098 /* If we are initializing something from a TARGET_EXPR, strip the
3099 TARGET_EXPR and initialize it directly, if possible. This can't
3100 be done if the initializer is void, since that implies that the
3101 temporary is set in some non-trivial way.
3103 ??? What about code that pulls out the temp and uses it
3104 elsewhere? I think that such code never uses the TARGET_EXPR as
3105 an initializer. If I'm wrong, we'll die because the temp won't
3106 have any RTL. In that case, I guess we'll need to replace
3107 references somehow. */
3108 tree init = TARGET_EXPR_INITIAL (*from_p);
3110 if (!VOID_TYPE_P (TREE_TYPE (init)))
3121 /* Remove any COMPOUND_EXPR in the RHS so the following cases will be
3123 gimplify_compound_expr (from_p, pre_p, true);
3128 /* If we're initializing from a CONSTRUCTOR, break this into
3129 individual MODIFY_EXPRs. */
3130 return gimplify_init_constructor (expr_p, pre_p, post_p, want_value);
3133 /* If we're assigning to a non-register type, push the assignment
3134 down into the branches. This is mandatory for ADDRESSABLE types,
3135 since we cannot generate temporaries for such, but it saves a
3136 copy in other cases as well. */
3137 if (!is_gimple_reg_type (TREE_TYPE (*from_p)))
3139 /* This code should mirror the code in gimplify_cond_expr. */
3140 enum tree_code code = TREE_CODE (*expr_p);
3141 tree cond = *from_p;
3142 tree result = *to_p;
3144 ret = gimplify_expr (&result, pre_p, post_p,
3145 is_gimple_min_lval, fb_lvalue);
3146 if (ret != GS_ERROR)
3149 if (TREE_TYPE (TREE_OPERAND (cond, 1)) != void_type_node)
3150 TREE_OPERAND (cond, 1)
3151 = build2 (code, void_type_node, result,
3152 TREE_OPERAND (cond, 1));
3153 if (TREE_TYPE (TREE_OPERAND (cond, 2)) != void_type_node)
3154 TREE_OPERAND (cond, 2)
3155 = build2 (code, void_type_node, unshare_expr (result),
3156 TREE_OPERAND (cond, 2));
3158 TREE_TYPE (cond) = void_type_node;
3159 recalculate_side_effects (cond);
3163 gimplify_and_add (cond, pre_p);
3164 *expr_p = unshare_expr (result);
3175 /* For calls that return in memory, give *to_p as the CALL_EXPR's
3176 return slot so that we don't generate a temporary. */
3177 if (!CALL_EXPR_RETURN_SLOT_OPT (*from_p)
3178 && aggregate_value_p (*from_p, *from_p))
3182 if (!(rhs_predicate_for (*to_p))(*from_p))
3183 /* If we need a temporary, *to_p isn't accurate. */
3185 else if (TREE_CODE (*to_p) == RESULT_DECL
3186 && DECL_NAME (*to_p) == NULL_TREE
3187 && needs_to_live_in_memory (*to_p))
3188 /* It's OK to use the return slot directly unless it's an NRV. */
3190 else if (is_gimple_reg_type (TREE_TYPE (*to_p))
3191 || (DECL_P (*to_p) && DECL_REGISTER (*to_p)))
3192 /* Don't force regs into memory. */
3194 else if (TREE_CODE (*to_p) == VAR_DECL
3195 && DECL_GIMPLE_FORMAL_TEMP_P (*to_p))
3196 /* Don't use the original target if it's a formal temp; we
3197 don't want to take their addresses. */
3199 else if (TREE_CODE (*expr_p) == INIT_EXPR)
3200 /* It's OK to use the target directly if it's being
3203 else if (!is_gimple_non_addressable (*to_p))
3204 /* Don't use the original target if it's already addressable;
3205 if its address escapes, and the called function uses the
3206 NRV optimization, a conforming program could see *to_p
3207 change before the called function returns; see c++/19317.
3208 When optimizing, the return_slot pass marks more functions
3209 as safe after we have escape info. */
3216 CALL_EXPR_RETURN_SLOT_OPT (*from_p) = 1;
3217 lang_hooks.mark_addressable (*to_p);
3232 /* Promote partial stores to COMPLEX variables to total stores. *EXPR_P is
3233 a MODIFY_EXPR with a lhs of a REAL/IMAGPART_EXPR of a variable with
3234 DECL_COMPLEX_GIMPLE_REG_P set. */
3236 static enum gimplify_status
3237 gimplify_modify_expr_complex_part (tree *expr_p, tree *pre_p, bool want_value)
3239 enum tree_code code, ocode;
3240 tree lhs, rhs, new_rhs, other, realpart, imagpart;
3242 lhs = TREE_OPERAND (*expr_p, 0);
3243 rhs = TREE_OPERAND (*expr_p, 1);
3244 code = TREE_CODE (lhs);
3245 lhs = TREE_OPERAND (lhs, 0);
3247 ocode = code == REALPART_EXPR ? IMAGPART_EXPR : REALPART_EXPR;
3248 other = build1 (ocode, TREE_TYPE (rhs), lhs);
3249 other = get_formal_tmp_var (other, pre_p);
3251 realpart = code == REALPART_EXPR ? rhs : other;
3252 imagpart = code == REALPART_EXPR ? other : rhs;
3254 if (TREE_CONSTANT (realpart) && TREE_CONSTANT (imagpart))
3255 new_rhs = build_complex (TREE_TYPE (lhs), realpart, imagpart);
3257 new_rhs = build2 (COMPLEX_EXPR, TREE_TYPE (lhs), realpart, imagpart);
3259 TREE_OPERAND (*expr_p, 0) = lhs;
3260 TREE_OPERAND (*expr_p, 1) = new_rhs;
3264 append_to_statement_list (*expr_p, pre_p);
3271 /* Gimplify the MODIFY_EXPR node pointed to by EXPR_P.
3277 PRE_P points to the list where side effects that must happen before
3278 *EXPR_P should be stored.
3280 POST_P points to the list where side effects that must happen after
3281 *EXPR_P should be stored.
3283 WANT_VALUE is nonzero iff we want to use the value of this expression
3284 in another expression. */
3286 static enum gimplify_status
3287 gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value)
3289 tree *from_p = &TREE_OPERAND (*expr_p, 1);
3290 tree *to_p = &TREE_OPERAND (*expr_p, 0);
3291 enum gimplify_status ret = GS_UNHANDLED;
3293 gcc_assert (TREE_CODE (*expr_p) == MODIFY_EXPR
3294 || TREE_CODE (*expr_p) == INIT_EXPR);
3296 /* For zero sized types only gimplify the left hand side and right hand side
3297 as statements and throw away the assignment. */
3298 if (zero_sized_type (TREE_TYPE (*from_p)))
3300 gimplify_stmt (from_p);
3301 gimplify_stmt (to_p);
3302 append_to_statement_list (*from_p, pre_p);
3303 append_to_statement_list (*to_p, pre_p);
3304 *expr_p = NULL_TREE;
3308 /* See if any simplifications can be done based on what the RHS is. */
3309 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
3311 if (ret != GS_UNHANDLED)
3314 /* If the value being copied is of variable width, compute the length
3315 of the copy into a WITH_SIZE_EXPR. Note that we need to do this
3316 before gimplifying any of the operands so that we can resolve any
3317 PLACEHOLDER_EXPRs in the size. Also note that the RTL expander uses
3318 the size of the expression to be copied, not of the destination, so
3319 that is what we must here. */
3320 maybe_with_size_expr (from_p);
3322 ret = gimplify_expr (to_p, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
3323 if (ret == GS_ERROR)
3326 ret = gimplify_expr (from_p, pre_p, post_p,
3327 rhs_predicate_for (*to_p), fb_rvalue);
3328 if (ret == GS_ERROR)
3331 /* Now see if the above changed *from_p to something we handle specially. */
3332 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
3334 if (ret != GS_UNHANDLED)
3337 /* If we've got a variable sized assignment between two lvalues (i.e. does
3338 not involve a call), then we can make things a bit more straightforward
3339 by converting the assignment to memcpy or memset. */
3340 if (TREE_CODE (*from_p) == WITH_SIZE_EXPR)
3342 tree from = TREE_OPERAND (*from_p, 0);
3343 tree size = TREE_OPERAND (*from_p, 1);
3345 if (TREE_CODE (from) == CONSTRUCTOR)
3346 return gimplify_modify_expr_to_memset (expr_p, size, want_value);
3347 if (is_gimple_addressable (from))
3350 return gimplify_modify_expr_to_memcpy (expr_p, size, want_value);
3354 /* Transform partial stores to non-addressable complex variables into
3355 total stores. This allows us to use real instead of virtual operands
3356 for these variables, which improves optimization. */
3357 if ((TREE_CODE (*to_p) == REALPART_EXPR
3358 || TREE_CODE (*to_p) == IMAGPART_EXPR)
3359 && is_gimple_reg (TREE_OPERAND (*to_p, 0)))
3360 return gimplify_modify_expr_complex_part (expr_p, pre_p, want_value);
3362 if (gimplify_ctxp->into_ssa && is_gimple_reg (*to_p))
3364 /* If we've somehow already got an SSA_NAME on the LHS, then
3365 we're probably modified it twice. Not good. */
3366 gcc_assert (TREE_CODE (*to_p) != SSA_NAME);
3367 *to_p = make_ssa_name (*to_p, *expr_p);
3372 append_to_statement_list (*expr_p, pre_p);
3380 /* Gimplify a comparison between two variable-sized objects. Do this
3381 with a call to BUILT_IN_MEMCMP. */
3383 static enum gimplify_status
3384 gimplify_variable_sized_compare (tree *expr_p)
3386 tree op0 = TREE_OPERAND (*expr_p, 0);
3387 tree op1 = TREE_OPERAND (*expr_p, 1);
3390 t = TYPE_SIZE_UNIT (TREE_TYPE (op0));
3391 t = unshare_expr (t);
3392 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, op0);
3393 args = tree_cons (NULL, t, NULL);
3394 t = build_fold_addr_expr (op1);
3395 args = tree_cons (NULL, t, args);
3396 dest = build_fold_addr_expr (op0);
3397 args = tree_cons (NULL, dest, args);
3398 t = implicit_built_in_decls[BUILT_IN_MEMCMP];
3399 t = build_function_call_expr (t, args);
3401 = build (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), t, integer_zero_node);
3406 /* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P
3407 points to the expression to gimplify.
3409 Expressions of the form 'a && b' are gimplified to:
3411 a && b ? true : false
3413 gimplify_cond_expr will do the rest.
3415 PRE_P points to the list where side effects that must happen before
3416 *EXPR_P should be stored. */
3418 static enum gimplify_status
3419 gimplify_boolean_expr (tree *expr_p)
3421 /* Preserve the original type of the expression. */
3422 tree type = TREE_TYPE (*expr_p);
3424 *expr_p = build (COND_EXPR, type, *expr_p,
3425 convert (type, boolean_true_node),
3426 convert (type, boolean_false_node));
3431 /* Gimplifies an expression sequence. This function gimplifies each
3432 expression and re-writes the original expression with the last
3433 expression of the sequence in GIMPLE form.
3435 PRE_P points to the list where the side effects for all the
3436 expressions in the sequence will be emitted.
3438 WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */
3439 /* ??? Should rearrange to share the pre-queue with all the indirect
3440 invocations of gimplify_expr. Would probably save on creations
3441 of statement_list nodes. */
3443 static enum gimplify_status
3444 gimplify_compound_expr (tree *expr_p, tree *pre_p, bool want_value)
3450 tree *sub_p = &TREE_OPERAND (t, 0);
3452 if (TREE_CODE (*sub_p) == COMPOUND_EXPR)
3453 gimplify_compound_expr (sub_p, pre_p, false);
3455 gimplify_stmt (sub_p);
3456 append_to_statement_list (*sub_p, pre_p);
3458 t = TREE_OPERAND (t, 1);
3460 while (TREE_CODE (t) == COMPOUND_EXPR);
3467 gimplify_stmt (expr_p);
3472 /* Gimplifies a statement list. These may be created either by an
3473 enlightened front-end, or by shortcut_cond_expr. */
3475 static enum gimplify_status
3476 gimplify_statement_list (tree *expr_p)
3478 tree_stmt_iterator i = tsi_start (*expr_p);
3480 while (!tsi_end_p (i))
3484 gimplify_stmt (tsi_stmt_ptr (i));
3489 else if (TREE_CODE (t) == STATEMENT_LIST)
3491 tsi_link_before (&i, t, TSI_SAME_STMT);
3501 /* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to
3502 gimplify. After gimplification, EXPR_P will point to a new temporary
3503 that holds the original value of the SAVE_EXPR node.
3505 PRE_P points to the list where side effects that must happen before
3506 *EXPR_P should be stored. */
3508 static enum gimplify_status
3509 gimplify_save_expr (tree *expr_p, tree *pre_p, tree *post_p)
3511 enum gimplify_status ret = GS_ALL_DONE;
3514 gcc_assert (TREE_CODE (*expr_p) == SAVE_EXPR);
3515 val = TREE_OPERAND (*expr_p, 0);
3517 /* If the SAVE_EXPR has not been resolved, then evaluate it once. */
3518 if (!SAVE_EXPR_RESOLVED_P (*expr_p))
3520 /* The operand may be a void-valued expression such as SAVE_EXPRs
3521 generated by the Java frontend for class initialization. It is
3522 being executed only for its side-effects. */
3523 if (TREE_TYPE (val) == void_type_node)
3525 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3526 is_gimple_stmt, fb_none);
3527 append_to_statement_list (TREE_OPERAND (*expr_p, 0), pre_p);
3531 val = get_initialized_tmp_var (val, pre_p, post_p);
3533 TREE_OPERAND (*expr_p, 0) = val;
3534 SAVE_EXPR_RESOLVED_P (*expr_p) = 1;
3542 /* Re-write the ADDR_EXPR node pointed to by EXPR_P
3549 PRE_P points to the list where side effects that must happen before
3550 *EXPR_P should be stored.
3552 POST_P points to the list where side effects that must happen after
3553 *EXPR_P should be stored. */
3555 static enum gimplify_status
3556 gimplify_addr_expr (tree *expr_p, tree *pre_p, tree *post_p)
3558 tree expr = *expr_p;
3559 tree op0 = TREE_OPERAND (expr, 0);
3560 enum gimplify_status ret;
3562 switch (TREE_CODE (op0))
3565 case MISALIGNED_INDIRECT_REF:
3567 /* Check if we are dealing with an expression of the form '&*ptr'.
3568 While the front end folds away '&*ptr' into 'ptr', these
3569 expressions may be generated internally by the compiler (e.g.,
3570 builtins like __builtin_va_end). */
3571 /* Caution: the silent array decomposition semantics we allow for
3572 ADDR_EXPR means we can't always discard the pair. */
3573 /* Gimplification of the ADDR_EXPR operand may drop
3574 cv-qualification conversions, so make sure we add them if
3577 tree op00 = TREE_OPERAND (op0, 0);
3578 tree t_expr = TREE_TYPE (expr);
3579 tree t_op00 = TREE_TYPE (op00);
3581 if (!lang_hooks.types_compatible_p (t_expr, t_op00))
3583 #ifdef ENABLE_CHECKING
3584 tree t_op0 = TREE_TYPE (op0);
3585 gcc_assert (POINTER_TYPE_P (t_expr)
3586 && cpt_same_type (TREE_CODE (t_op0) == ARRAY_TYPE
3587 ? TREE_TYPE (t_op0) : t_op0,
3589 && POINTER_TYPE_P (t_op00)
3590 && cpt_same_type (t_op0, TREE_TYPE (t_op00)));
3592 op00 = fold_convert (TREE_TYPE (expr), op00);
3599 case VIEW_CONVERT_EXPR:
3600 /* Take the address of our operand and then convert it to the type of
3603 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3604 all clear. The impact of this transformation is even less clear. */
3606 /* If the operand is a useless conversion, look through it. Doing so
3607 guarantees that the ADDR_EXPR and its operand will remain of the
3609 if (tree_ssa_useless_type_conversion (TREE_OPERAND (op0, 0)))
3610 op0 = TREE_OPERAND (op0, 0);
3612 *expr_p = fold_convert (TREE_TYPE (expr),
3613 build_fold_addr_expr (TREE_OPERAND (op0, 0)));
3618 /* We use fb_either here because the C frontend sometimes takes
3619 the address of a call that returns a struct; see
3620 gcc.dg/c99-array-lval-1.c. The gimplifier will correctly make
3621 the implied temporary explicit. */
3622 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, post_p,
3623 is_gimple_addressable, fb_either);
3624 if (ret != GS_ERROR)
3626 op0 = TREE_OPERAND (expr, 0);
3628 /* For various reasons, the gimplification of the expression
3629 may have made a new INDIRECT_REF. */
3630 if (TREE_CODE (op0) == INDIRECT_REF)
3631 goto do_indirect_ref;
3633 /* Make sure TREE_INVARIANT, TREE_CONSTANT, and TREE_SIDE_EFFECTS
3635 recompute_tree_invarant_for_addr_expr (expr);
3637 /* Mark the RHS addressable. */
3638 lang_hooks.mark_addressable (TREE_OPERAND (expr, 0));
3646 /* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple
3647 value; output operands should be a gimple lvalue. */
3649 static enum gimplify_status
3650 gimplify_asm_expr (tree *expr_p, tree *pre_p, tree *post_p)
3652 tree expr = *expr_p;
3653 int noutputs = list_length (ASM_OUTPUTS (expr));
3654 const char **oconstraints
3655 = (const char **) alloca ((noutputs) * sizeof (const char *));
3658 const char *constraint;
3659 bool allows_mem, allows_reg, is_inout;
3660 enum gimplify_status ret, tret;
3663 for (i = 0, link = ASM_OUTPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3665 size_t constraint_len;
3666 oconstraints[i] = constraint
3667 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3668 constraint_len = strlen (constraint);
3669 if (constraint_len == 0)
3672 parse_output_constraint (&constraint, i, 0, 0,
3673 &allows_mem, &allows_reg, &is_inout);
3675 if (!allows_reg && allows_mem)
3676 lang_hooks.mark_addressable (TREE_VALUE (link));
3678 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3679 is_inout ? is_gimple_min_lval : is_gimple_lvalue,
3680 fb_lvalue | fb_mayfail);
3681 if (tret == GS_ERROR)
3683 error ("invalid lvalue in asm output %d", i);
3689 /* An input/output operand. To give the optimizers more
3690 flexibility, split it into separate input and output
3695 /* Turn the in/out constraint into an output constraint. */
3696 char *p = xstrdup (constraint);
3698 TREE_VALUE (TREE_PURPOSE (link)) = build_string (constraint_len, p);
3700 /* And add a matching input constraint. */
3703 sprintf (buf, "%d", i);
3705 /* If there are multiple alternatives in the constraint,
3706 handle each of them individually. Those that allow register
3707 will be replaced with operand number, the others will stay
3709 if (strchr (p, ',') != NULL)
3711 size_t len = 0, buflen = strlen (buf);
3712 char *beg, *end, *str, *dst;
3716 end = strchr (beg, ',');
3718 end = strchr (beg, '\0');
3719 if ((size_t) (end - beg) < buflen)
3722 len += end - beg + 1;
3730 for (beg = p + 1, dst = str;;)
3733 bool mem_p, reg_p, inout_p;
3735 end = strchr (beg, ',');
3740 parse_output_constraint (&tem, i, 0, 0,
3741 &mem_p, ®_p, &inout_p);
3746 memcpy (dst, buf, buflen);
3755 memcpy (dst, beg, len);
3764 input = build_string (dst - str, str);
3767 input = build_string (strlen (buf), buf);
3770 input = build_string (constraint_len - 1, constraint + 1);
3774 input = build_tree_list (build_tree_list (NULL_TREE, input),
3775 unshare_expr (TREE_VALUE (link)));
3776 ASM_INPUTS (expr) = chainon (ASM_INPUTS (expr), input);
3780 for (link = ASM_INPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3783 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3784 parse_input_constraint (&constraint, 0, 0, noutputs, 0,
3785 oconstraints, &allows_mem, &allows_reg);
3787 /* If the operand is a memory input, it should be an lvalue. */
3788 if (!allows_reg && allows_mem)
3790 lang_hooks.mark_addressable (TREE_VALUE (link));
3791 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3792 is_gimple_lvalue, fb_lvalue | fb_mayfail);
3793 if (tret == GS_ERROR)
3795 error ("memory input %d is not directly addressable", i);
3801 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3802 is_gimple_asm_val, fb_rvalue);
3803 if (tret == GS_ERROR)
3811 /* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding
3812 WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
3813 gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
3814 return to this function.
3816 FIXME should we complexify the prequeue handling instead? Or use flags
3817 for all the cleanups and let the optimizer tighten them up? The current
3818 code seems pretty fragile; it will break on a cleanup within any
3819 non-conditional nesting. But any such nesting would be broken, anyway;
3820 we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
3821 and continues out of it. We can do that at the RTL level, though, so
3822 having an optimizer to tighten up try/finally regions would be a Good
3825 static enum gimplify_status
3826 gimplify_cleanup_point_expr (tree *expr_p, tree *pre_p)
3828 tree_stmt_iterator iter;
3831 tree temp = voidify_wrapper_expr (*expr_p, NULL);
3833 /* We only care about the number of conditions between the innermost
3834 CLEANUP_POINT_EXPR and the cleanup. So save and reset the count and
3835 any cleanups collected outside the CLEANUP_POINT_EXPR. */
3836 int old_conds = gimplify_ctxp->conditions;
3837 tree old_cleanups = gimplify_ctxp->conditional_cleanups;
3838 gimplify_ctxp->conditions = 0;
3839 gimplify_ctxp->conditional_cleanups = NULL_TREE;
3841 body = TREE_OPERAND (*expr_p, 0);
3842 gimplify_to_stmt_list (&body);
3844 gimplify_ctxp->conditions = old_conds;
3845 gimplify_ctxp->conditional_cleanups = old_cleanups;
3847 for (iter = tsi_start (body); !tsi_end_p (iter); )
3849 tree *wce_p = tsi_stmt_ptr (iter);
3852 if (TREE_CODE (wce) == WITH_CLEANUP_EXPR)
3854 if (tsi_one_before_end_p (iter))
3856 tsi_link_before (&iter, TREE_OPERAND (wce, 0), TSI_SAME_STMT);
3863 enum tree_code code;
3865 if (CLEANUP_EH_ONLY (wce))
3866 code = TRY_CATCH_EXPR;
3868 code = TRY_FINALLY_EXPR;
3870 sl = tsi_split_statement_list_after (&iter);
3871 tfe = build (code, void_type_node, sl, NULL_TREE);
3872 append_to_statement_list (TREE_OPERAND (wce, 0),
3873 &TREE_OPERAND (tfe, 1));
3875 iter = tsi_start (sl);
3885 append_to_statement_list (body, pre_p);
3895 /* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP
3896 is the cleanup action required. */
3899 gimple_push_cleanup (tree var, tree cleanup, bool eh_only, tree *pre_p)
3903 /* Errors can result in improperly nested cleanups. Which results in
3904 confusion when trying to resolve the WITH_CLEANUP_EXPR. */
3905 if (errorcount || sorrycount)
3908 if (gimple_conditional_context ())
3910 /* If we're in a conditional context, this is more complex. We only
3911 want to run the cleanup if we actually ran the initialization that
3912 necessitates it, but we want to run it after the end of the
3913 conditional context. So we wrap the try/finally around the
3914 condition and use a flag to determine whether or not to actually
3915 run the destructor. Thus
3919 becomes (approximately)
3923 if (test) { A::A(temp); flag = 1; val = f(temp); }
3926 if (flag) A::~A(temp);
3931 tree flag = create_tmp_var (boolean_type_node, "cleanup");
3932 tree ffalse = build (MODIFY_EXPR, void_type_node, flag,
3933 boolean_false_node);
3934 tree ftrue = build (MODIFY_EXPR, void_type_node, flag,
3936 cleanup = build (COND_EXPR, void_type_node, flag, cleanup, NULL);
3937 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3938 append_to_statement_list (ffalse, &gimplify_ctxp->conditional_cleanups);
3939 append_to_statement_list (wce, &gimplify_ctxp->conditional_cleanups);
3940 append_to_statement_list (ftrue, pre_p);
3942 /* Because of this manipulation, and the EH edges that jump
3943 threading cannot redirect, the temporary (VAR) will appear
3944 to be used uninitialized. Don't warn. */
3945 TREE_NO_WARNING (var) = 1;
3949 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3950 CLEANUP_EH_ONLY (wce) = eh_only;
3951 append_to_statement_list (wce, pre_p);
3954 gimplify_stmt (&TREE_OPERAND (wce, 0));
3957 /* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */
3959 static enum gimplify_status
3960 gimplify_target_expr (tree *expr_p, tree *pre_p, tree *post_p)
3962 tree targ = *expr_p;
3963 tree temp = TARGET_EXPR_SLOT (targ);
3964 tree init = TARGET_EXPR_INITIAL (targ);
3965 enum gimplify_status ret;
3969 /* TARGET_EXPR temps aren't part of the enclosing block, so add it
3970 to the temps list. */
3971 gimple_add_tmp_var (temp);
3973 /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
3974 expression is supposed to initialize the slot. */
3975 if (VOID_TYPE_P (TREE_TYPE (init)))
3976 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, fb_none);
3979 /* Special handling for BIND_EXPR can result in fewer temps. */
3981 if (TREE_CODE (init) == BIND_EXPR)
3982 gimplify_bind_expr (&init, temp, pre_p);
3985 init = build2 (INIT_EXPR, void_type_node, temp, init);
3986 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt,
3990 if (ret == GS_ERROR)
3992 append_to_statement_list (init, pre_p);
3994 /* If needed, push the cleanup for the temp. */
3995 if (TARGET_EXPR_CLEANUP (targ))
3997 gimplify_stmt (&TARGET_EXPR_CLEANUP (targ));
3998 gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ),
3999 CLEANUP_EH_ONLY (targ), pre_p);
4002 /* Only expand this once. */
4003 TREE_OPERAND (targ, 3) = init;
4004 TARGET_EXPR_INITIAL (targ) = NULL_TREE;
4007 /* We should have expanded this before. */
4008 gcc_assert (DECL_SEEN_IN_BIND_EXPR_P (temp));
4014 /* Gimplification of expression trees. */
4016 /* Gimplify an expression which appears at statement context; usually, this
4017 means replacing it with a suitably gimple STATEMENT_LIST. */
4020 gimplify_stmt (tree *stmt_p)
4022 gimplify_expr (stmt_p, NULL, NULL, is_gimple_stmt, fb_none);
4025 /* Similarly, but force the result to be a STATEMENT_LIST. */
4028 gimplify_to_stmt_list (tree *stmt_p)
4030 gimplify_stmt (stmt_p);
4032 *stmt_p = alloc_stmt_list ();
4033 else if (TREE_CODE (*stmt_p) != STATEMENT_LIST)
4036 *stmt_p = alloc_stmt_list ();
4037 append_to_statement_list (t, stmt_p);
4042 /* Gimplifies the expression tree pointed to by EXPR_P. Return 0 if
4043 gimplification failed.
4045 PRE_P points to the list where side effects that must happen before
4046 EXPR should be stored.
4048 POST_P points to the list where side effects that must happen after
4049 EXPR should be stored, or NULL if there is no suitable list. In
4050 that case, we copy the result to a temporary, emit the
4051 post-effects, and then return the temporary.
4053 GIMPLE_TEST_F points to a function that takes a tree T and
4054 returns nonzero if T is in the GIMPLE form requested by the
4055 caller. The GIMPLE predicates are in tree-gimple.c.
4057 This test is used twice. Before gimplification, the test is
4058 invoked to determine whether *EXPR_P is already gimple enough. If
4059 that fails, *EXPR_P is gimplified according to its code and
4060 GIMPLE_TEST_F is called again. If the test still fails, then a new
4061 temporary variable is created and assigned the value of the
4062 gimplified expression.
4064 FALLBACK tells the function what sort of a temporary we want. If the 1
4065 bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK.
4066 If both are set, either is OK, but an lvalue is preferable.
4068 The return value is either GS_ERROR or GS_ALL_DONE, since this function
4069 iterates until solution. */
4071 enum gimplify_status
4072 gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
4073 bool (* gimple_test_f) (tree), fallback_t fallback)
4076 tree internal_pre = NULL_TREE;
4077 tree internal_post = NULL_TREE;
4079 int is_statement = (pre_p == NULL);
4080 location_t saved_location;
4081 enum gimplify_status ret;
4083 save_expr = *expr_p;
4084 if (save_expr == NULL_TREE)
4087 /* We used to check the predicate here and return immediately if it
4088 succeeds. This is wrong; the design is for gimplification to be
4089 idempotent, and for the predicates to only test for valid forms, not
4090 whether they are fully simplified. */
4092 /* Set up our internal queues if needed. */
4094 pre_p = &internal_pre;
4096 post_p = &internal_post;
4098 saved_location = input_location;
4099 if (save_expr != error_mark_node
4100 && EXPR_HAS_LOCATION (*expr_p))
4101 input_location = EXPR_LOCATION (*expr_p);
4103 /* Loop over the specific gimplifiers until the toplevel node
4104 remains the same. */
4107 /* Strip away as many useless type conversions as possible
4109 STRIP_USELESS_TYPE_CONVERSION (*expr_p);
4111 /* Remember the expr. */
4112 save_expr = *expr_p;
4114 /* Die, die, die, my darling. */
4115 if (save_expr == error_mark_node
4116 || (TREE_TYPE (save_expr)
4117 && TREE_TYPE (save_expr) == error_mark_node))
4123 /* Do any language-specific gimplification. */
4124 ret = lang_hooks.gimplify_expr (expr_p, pre_p, post_p);
4127 if (*expr_p == NULL_TREE)
4129 if (*expr_p != save_expr)
4132 else if (ret != GS_UNHANDLED)
4136 switch (TREE_CODE (*expr_p))
4138 /* First deal with the special cases. */
4140 case POSTINCREMENT_EXPR:
4141 case POSTDECREMENT_EXPR:
4142 case PREINCREMENT_EXPR:
4143 case PREDECREMENT_EXPR:
4144 ret = gimplify_self_mod_expr (expr_p, pre_p, post_p,
4145 fallback != fb_none);
4149 case ARRAY_RANGE_REF:
4153 case VIEW_CONVERT_EXPR:
4154 ret = gimplify_compound_lval (expr_p, pre_p, post_p,
4155 fallback ? fallback : fb_rvalue);
4159 ret = gimplify_cond_expr (expr_p, pre_p, fallback);
4160 /* C99 code may assign to an array in a structure value of a
4161 conditional expression, and this has undefined behavior
4162 only on execution, so create a temporary if an lvalue is
4164 if (fallback == fb_lvalue)
4166 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
4167 lang_hooks.mark_addressable (*expr_p);
4172 ret = gimplify_call_expr (expr_p, pre_p, fallback != fb_none);
4173 /* C99 code may assign to an array in a structure returned
4174 from a function, and this has undefined behavior only on
4175 execution, so create a temporary if an lvalue is
4177 if (fallback == fb_lvalue)
4179 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
4180 lang_hooks.mark_addressable (*expr_p);
4188 ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none);
4193 ret = gimplify_modify_expr (expr_p, pre_p, post_p,
4194 fallback != fb_none);
4196 /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer
4198 if (*expr_p && TREE_CODE (*expr_p) == INIT_EXPR)
4199 TREE_SET_CODE (*expr_p, MODIFY_EXPR);
4202 case TRUTH_ANDIF_EXPR:
4203 case TRUTH_ORIF_EXPR:
4204 ret = gimplify_boolean_expr (expr_p);
4207 case TRUTH_NOT_EXPR:
4208 TREE_OPERAND (*expr_p, 0)
4209 = gimple_boolify (TREE_OPERAND (*expr_p, 0));
4210 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4211 is_gimple_val, fb_rvalue);
4212 recalculate_side_effects (*expr_p);
4216 ret = gimplify_addr_expr (expr_p, pre_p, post_p);
4220 ret = gimplify_va_arg_expr (expr_p, pre_p, post_p);
4225 if (IS_EMPTY_STMT (*expr_p))
4231 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
4232 || fallback == fb_none)
4234 /* Just strip a conversion to void (or in void context) and
4236 *expr_p = TREE_OPERAND (*expr_p, 0);
4240 ret = gimplify_conversion (expr_p);
4241 if (ret == GS_ERROR)
4243 if (*expr_p != save_expr)
4247 case FIX_TRUNC_EXPR:
4249 case FIX_FLOOR_EXPR:
4250 case FIX_ROUND_EXPR:
4251 /* unary_expr: ... | '(' cast ')' val | ... */
4252 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4253 is_gimple_val, fb_rvalue);
4254 recalculate_side_effects (*expr_p);
4258 *expr_p = fold_indirect_ref (*expr_p);
4259 if (*expr_p != save_expr)
4261 /* else fall through. */
4262 case ALIGN_INDIRECT_REF:
4263 case MISALIGNED_INDIRECT_REF:
4264 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4265 is_gimple_reg, fb_rvalue);
4266 recalculate_side_effects (*expr_p);
4269 /* Constants need not be gimplified. */
4279 /* If we require an lvalue, such as for ADDR_EXPR, retain the
4280 CONST_DECL node. Otherwise the decl is replaceable by its
4282 /* ??? Should be == fb_lvalue, but ADDR_EXPR passes fb_either. */
4283 if (fallback & fb_lvalue)
4286 *expr_p = DECL_INITIAL (*expr_p);
4290 ret = gimplify_decl_expr (expr_p);
4294 /* FIXME make this a decl. */
4299 ret = gimplify_bind_expr (expr_p, NULL, pre_p);
4303 ret = gimplify_loop_expr (expr_p, pre_p);
4307 ret = gimplify_switch_expr (expr_p, pre_p);
4311 ret = gimplify_exit_expr (expr_p);
4315 /* If the target is not LABEL, then it is a computed jump
4316 and the target needs to be gimplified. */
4317 if (TREE_CODE (GOTO_DESTINATION (*expr_p)) != LABEL_DECL)
4318 ret = gimplify_expr (&GOTO_DESTINATION (*expr_p), pre_p,
4319 NULL, is_gimple_val, fb_rvalue);
4324 gcc_assert (decl_function_context (LABEL_EXPR_LABEL (*expr_p))
4325 == current_function_decl);
4328 case CASE_LABEL_EXPR:
4329 ret = gimplify_case_label_expr (expr_p);
4333 ret = gimplify_return_expr (*expr_p, pre_p);
4337 /* Don't reduce this in place; let gimplify_init_constructor work its
4338 magic. Buf if we're just elaborating this for side effects, just
4339 gimplify any element that has side-effects. */
4340 if (fallback == fb_none)
4342 unsigned HOST_WIDE_INT ix;
4343 constructor_elt *ce;
4344 tree temp = NULL_TREE;
4346 VEC_iterate (constructor_elt, CONSTRUCTOR_ELTS (*expr_p),
4349 if (TREE_SIDE_EFFECTS (ce->value))
4350 append_to_statement_list (ce->value, &temp);
4355 /* C99 code may assign to an array in a constructed
4356 structure or union, and this has undefined behavior only
4357 on execution, so create a temporary if an lvalue is
4359 else if (fallback == fb_lvalue)
4361 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
4362 lang_hooks.mark_addressable (*expr_p);
4368 /* The following are special cases that are not handled by the
4369 original GIMPLE grammar. */
4371 /* SAVE_EXPR nodes are converted into a GIMPLE identifier and
4374 ret = gimplify_save_expr (expr_p, pre_p, post_p);
4379 enum gimplify_status r0, r1, r2;
4381 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4382 is_gimple_lvalue, fb_either);
4383 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
4384 is_gimple_val, fb_rvalue);
4385 r2 = gimplify_expr (&TREE_OPERAND (*expr_p, 2), pre_p, post_p,
4386 is_gimple_val, fb_rvalue);
4387 recalculate_side_effects (*expr_p);
4389 ret = MIN (r0, MIN (r1, r2));
4393 case NON_LVALUE_EXPR:
4394 /* This should have been stripped above. */
4398 ret = gimplify_asm_expr (expr_p, pre_p, post_p);
4401 case TRY_FINALLY_EXPR:
4402 case TRY_CATCH_EXPR:
4403 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 0));
4404 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 1));
4408 case CLEANUP_POINT_EXPR:
4409 ret = gimplify_cleanup_point_expr (expr_p, pre_p);
4413 ret = gimplify_target_expr (expr_p, pre_p, post_p);
4417 gimplify_to_stmt_list (&CATCH_BODY (*expr_p));
4421 case EH_FILTER_EXPR:
4422 gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p));
4428 enum gimplify_status r0, r1;
4429 r0 = gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p), pre_p, post_p,
4430 is_gimple_val, fb_rvalue);
4431 r1 = gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p), pre_p, post_p,
4432 is_gimple_val, fb_rvalue);
4438 /* We get here when taking the address of a label. We mark
4439 the label as "forced"; meaning it can never be removed and
4440 it is a potential target for any computed goto. */
4441 FORCED_LABEL (*expr_p) = 1;
4445 case STATEMENT_LIST:
4446 ret = gimplify_statement_list (expr_p);
4449 case WITH_SIZE_EXPR:
4451 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
4452 post_p == &internal_post ? NULL : post_p,
4453 gimple_test_f, fallback);
4454 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
4455 is_gimple_val, fb_rvalue);
4461 ret = gimplify_var_or_parm_decl (expr_p);
4465 /* Allow callbacks into the gimplifier during optimization. */
4470 switch (TREE_CODE_CLASS (TREE_CODE (*expr_p)))
4472 case tcc_comparison:
4473 /* If this is a comparison of objects of aggregate type,
4474 handle it specially (by converting to a call to
4475 memcmp). It would be nice to only have to do this
4476 for variable-sized objects, but then we'd have to
4477 allow the same nest of reference nodes we allow for
4478 MODIFY_EXPR and that's too complex. */
4479 if (!AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 1))))
4481 ret = gimplify_variable_sized_compare (expr_p);
4484 /* If *EXPR_P does not need to be special-cased, handle it
4485 according to its class. */
4487 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
4488 post_p, is_gimple_val, fb_rvalue);
4494 enum gimplify_status r0, r1;
4496 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
4497 post_p, is_gimple_val, fb_rvalue);
4498 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p,
4499 post_p, is_gimple_val, fb_rvalue);
4505 case tcc_declaration:
4508 goto dont_recalculate;
4511 gcc_assert (TREE_CODE (*expr_p) == TRUTH_AND_EXPR
4512 || TREE_CODE (*expr_p) == TRUTH_OR_EXPR
4513 || TREE_CODE (*expr_p) == TRUTH_XOR_EXPR);
4517 recalculate_side_effects (*expr_p);
4522 /* If we replaced *expr_p, gimplify again. */
4523 if (ret == GS_OK && (*expr_p == NULL || *expr_p == save_expr))
4526 while (ret == GS_OK);
4528 /* If we encountered an error_mark somewhere nested inside, either
4529 stub out the statement or propagate the error back out. */
4530 if (ret == GS_ERROR)
4537 /* This was only valid as a return value from the langhook, which
4538 we handled. Make sure it doesn't escape from any other context. */
4539 gcc_assert (ret != GS_UNHANDLED);
4541 if (fallback == fb_none && *expr_p && !is_gimple_stmt (*expr_p))
4543 /* We aren't looking for a value, and we don't have a valid
4544 statement. If it doesn't have side-effects, throw it away. */
4545 if (!TREE_SIDE_EFFECTS (*expr_p))
4547 else if (!TREE_THIS_VOLATILE (*expr_p))
4549 /* This is probably a _REF that contains something nested that
4550 has side effects. Recurse through the operands to find it. */
4551 enum tree_code code = TREE_CODE (*expr_p);
4556 case REALPART_EXPR: case IMAGPART_EXPR:
4557 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4558 gimple_test_f, fallback);
4561 case ARRAY_REF: case ARRAY_RANGE_REF:
4562 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4563 gimple_test_f, fallback);
4564 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
4565 gimple_test_f, fallback);
4569 /* Anything else with side-effects must be converted to
4570 a valid statement before we get here. */
4576 else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p)))
4578 /* Historically, the compiler has treated a bare
4579 reference to a volatile lvalue as forcing a load. */
4580 tree type = TYPE_MAIN_VARIANT (TREE_TYPE (*expr_p));
4581 /* Normally, we do not want to create a temporary for a
4582 TREE_ADDRESSABLE type because such a type should not be
4583 copied by bitwise-assignment. However, we make an
4584 exception here, as all we are doing here is ensuring that
4585 we read the bytes that make up the type. We use
4586 create_tmp_var_raw because create_tmp_var will abort when
4587 given a TREE_ADDRESSABLE type. */
4588 tree tmp = create_tmp_var_raw (type, "vol");
4589 gimple_add_tmp_var (tmp);
4590 *expr_p = build (MODIFY_EXPR, type, tmp, *expr_p);
4593 /* We can't do anything useful with a volatile reference to
4594 incomplete type, so just throw it away. */
4598 /* If we are gimplifying at the statement level, we're done. Tack
4599 everything together and replace the original statement with the
4601 if (fallback == fb_none || is_statement)
4603 if (internal_pre || internal_post)
4605 append_to_statement_list (*expr_p, &internal_pre);
4606 append_to_statement_list (internal_post, &internal_pre);
4607 annotate_all_with_locus (&internal_pre, input_location);
4608 *expr_p = internal_pre;
4612 else if (TREE_CODE (*expr_p) == STATEMENT_LIST)
4613 annotate_all_with_locus (expr_p, input_location);
4615 annotate_one_with_locus (*expr_p, input_location);
4619 /* Otherwise we're gimplifying a subexpression, so the resulting value is
4622 /* If it's sufficiently simple already, we're done. Unless we are
4623 handling some post-effects internally; if that's the case, we need to
4624 copy into a temp before adding the post-effects to the tree. */
4625 if (!internal_post && (*gimple_test_f) (*expr_p))
4628 /* Otherwise, we need to create a new temporary for the gimplified
4631 /* We can't return an lvalue if we have an internal postqueue. The
4632 object the lvalue refers to would (probably) be modified by the
4633 postqueue; we need to copy the value out first, which means an
4635 if ((fallback & fb_lvalue) && !internal_post
4636 && is_gimple_addressable (*expr_p))
4638 /* An lvalue will do. Take the address of the expression, store it
4639 in a temporary, and replace the expression with an INDIRECT_REF of
4641 tmp = build_fold_addr_expr (*expr_p);
4642 gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue);
4643 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp);
4645 else if ((fallback & fb_rvalue) && is_gimple_formal_tmp_rhs (*expr_p))
4647 gcc_assert (!VOID_TYPE_P (TREE_TYPE (*expr_p)));
4649 /* An rvalue will do. Assign the gimplified expression into a new
4650 temporary TMP and replace the original expression with TMP. */
4652 if (internal_post || (fallback & fb_lvalue))
4653 /* The postqueue might change the value of the expression between
4654 the initialization and use of the temporary, so we can't use a
4655 formal temp. FIXME do we care? */
4656 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
4658 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
4660 if (TREE_CODE (*expr_p) != SSA_NAME)
4661 DECL_GIMPLE_FORMAL_TEMP_P (*expr_p) = 1;
4665 #ifdef ENABLE_CHECKING
4666 if (!(fallback & fb_mayfail))
4668 fprintf (stderr, "gimplification failed:\n");
4669 print_generic_expr (stderr, *expr_p, 0);
4670 debug_tree (*expr_p);
4671 internal_error ("gimplification failed");
4674 gcc_assert (fallback & fb_mayfail);
4675 /* If this is an asm statement, and the user asked for the
4676 impossible, don't die. Fail and let gimplify_asm_expr
4682 /* Make sure the temporary matches our predicate. */
4683 gcc_assert ((*gimple_test_f) (*expr_p));
4687 annotate_all_with_locus (&internal_post, input_location);
4688 append_to_statement_list (internal_post, pre_p);
4692 input_location = saved_location;
4696 /* Look through TYPE for variable-sized objects and gimplify each such
4697 size that we find. Add to LIST_P any statements generated. */
4700 gimplify_type_sizes (tree type, tree *list_p)
4704 if (type == NULL || type == error_mark_node)
4707 /* We first do the main variant, then copy into any other variants. */
4708 type = TYPE_MAIN_VARIANT (type);
4710 /* Avoid infinite recursion. */
4711 if (TYPE_SIZES_GIMPLIFIED (type))
4714 TYPE_SIZES_GIMPLIFIED (type) = 1;
4716 switch (TREE_CODE (type))
4723 gimplify_one_sizepos (&TYPE_MIN_VALUE (type), list_p);
4724 gimplify_one_sizepos (&TYPE_MAX_VALUE (type), list_p);
4726 for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
4728 TYPE_MIN_VALUE (t) = TYPE_MIN_VALUE (type);
4729 TYPE_MAX_VALUE (t) = TYPE_MAX_VALUE (type);
4734 /* These types may not have declarations, so handle them here. */
4735 gimplify_type_sizes (TREE_TYPE (type), list_p);
4736 gimplify_type_sizes (TYPE_DOMAIN (type), list_p);
4741 case QUAL_UNION_TYPE:
4742 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4743 if (TREE_CODE (field) == FIELD_DECL)
4745 gimplify_one_sizepos (&DECL_FIELD_OFFSET (field), list_p);
4746 gimplify_type_sizes (TREE_TYPE (field), list_p);
4751 case REFERENCE_TYPE:
4752 gimplify_type_sizes (TREE_TYPE (type), list_p);
4759 gimplify_one_sizepos (&TYPE_SIZE (type), list_p);
4760 gimplify_one_sizepos (&TYPE_SIZE_UNIT (type), list_p);
4762 for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
4764 TYPE_SIZE (t) = TYPE_SIZE (type);
4765 TYPE_SIZE_UNIT (t) = TYPE_SIZE_UNIT (type);
4766 TYPE_SIZES_GIMPLIFIED (t) = 1;
4770 /* A subroutine of gimplify_type_sizes to make sure that *EXPR_P,
4771 a size or position, has had all of its SAVE_EXPRs evaluated.
4772 We add any required statements to STMT_P. */
4775 gimplify_one_sizepos (tree *expr_p, tree *stmt_p)
4777 tree type, expr = *expr_p;
4779 /* We don't do anything if the value isn't there, is constant, or contains
4780 A PLACEHOLDER_EXPR. We also don't want to do anything if it's already
4781 a VAR_DECL. If it's a VAR_DECL from another function, the gimplifier
4782 will want to replace it with a new variable, but that will cause problems
4783 if this type is from outside the function. It's OK to have that here. */
4784 if (expr == NULL_TREE || TREE_CONSTANT (expr)
4785 || TREE_CODE (expr) == VAR_DECL
4786 || CONTAINS_PLACEHOLDER_P (expr))
4789 type = TREE_TYPE (expr);
4790 *expr_p = unshare_expr (expr);
4792 gimplify_expr (expr_p, stmt_p, NULL, is_gimple_val, fb_rvalue);
4795 /* Verify that we've an exact type match with the original expression.
4796 In particular, we do not wish to drop a "sizetype" in favour of a
4797 type of similar dimensions. We don't want to pollute the generic
4798 type-stripping code with this knowledge because it doesn't matter
4799 for the bulk of GENERIC/GIMPLE. It only matters that TYPE_SIZE_UNIT
4800 and friends retain their "sizetype-ness". */
4801 if (TREE_TYPE (expr) != type
4802 && TREE_CODE (type) == INTEGER_TYPE
4803 && TYPE_IS_SIZETYPE (type))
4807 *expr_p = create_tmp_var (type, NULL);
4808 tmp = build1 (NOP_EXPR, type, expr);
4809 tmp = build2 (MODIFY_EXPR, type, *expr_p, tmp);
4810 if (EXPR_HAS_LOCATION (expr))
4811 SET_EXPR_LOCUS (tmp, EXPR_LOCUS (expr));
4813 SET_EXPR_LOCATION (tmp, input_location);
4815 gimplify_and_add (tmp, stmt_p);
4819 #ifdef ENABLE_CHECKING
4820 /* Compare types A and B for a "close enough" match. */
4823 cpt_same_type (tree a, tree b)
4825 if (lang_hooks.types_compatible_p (a, b))
4828 /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't
4829 link them together. This routine is intended to catch type errors
4830 that will affect the optimizers, and the optimizers don't add new
4831 dereferences of function pointers, so ignore it. */
4832 if ((TREE_CODE (a) == FUNCTION_TYPE || TREE_CODE (a) == METHOD_TYPE)
4833 && (TREE_CODE (b) == FUNCTION_TYPE || TREE_CODE (b) == METHOD_TYPE))
4836 /* ??? The C FE pushes type qualifiers after the fact into the type of
4837 the element from the type of the array. See build_unary_op's handling
4838 of ADDR_EXPR. This seems wrong -- if we were going to do this, we
4839 should have done it when creating the variable in the first place.
4840 Alternately, why aren't the two array types made variants? */
4841 if (TREE_CODE (a) == ARRAY_TYPE && TREE_CODE (b) == ARRAY_TYPE)
4842 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4844 /* And because of those, we have to recurse down through pointers. */
4845 if (POINTER_TYPE_P (a) && POINTER_TYPE_P (b))
4846 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4851 /* Check for some cases of the front end missing cast expressions.
4852 The type of a dereference should correspond to the pointer type;
4853 similarly the type of an address should match its object. */
4856 check_pointer_types_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
4857 void *data ATTRIBUTE_UNUSED)
4860 tree ptype, otype, dtype;
4862 switch (TREE_CODE (t))
4866 otype = TREE_TYPE (t);
4867 ptype = TREE_TYPE (TREE_OPERAND (t, 0));
4868 dtype = TREE_TYPE (ptype);
4869 gcc_assert (cpt_same_type (otype, dtype));
4873 ptype = TREE_TYPE (t);
4874 otype = TREE_TYPE (TREE_OPERAND (t, 0));
4875 dtype = TREE_TYPE (ptype);
4876 if (!cpt_same_type (otype, dtype))
4878 /* &array is allowed to produce a pointer to the element, rather than
4879 a pointer to the array type. We must allow this in order to
4880 properly represent assigning the address of an array in C into
4881 pointer to the element type. */
4882 gcc_assert (TREE_CODE (otype) == ARRAY_TYPE
4883 && POINTER_TYPE_P (ptype)
4884 && cpt_same_type (TREE_TYPE (otype), dtype));
4898 /* Gimplify the body of statements pointed to by BODY_P. FNDECL is the
4899 function decl containing BODY. */
4902 gimplify_body (tree *body_p, tree fndecl, bool do_parms)
4904 location_t saved_location = input_location;
4905 tree body, parm_stmts;
4907 timevar_push (TV_TREE_GIMPLIFY);
4908 push_gimplify_context ();
4910 /* Unshare most shared trees in the body and in that of any nested functions.
4911 It would seem we don't have to do this for nested functions because
4912 they are supposed to be output and then the outer function gimplified
4913 first, but the g++ front end doesn't always do it that way. */
4914 unshare_body (body_p, fndecl);
4915 unvisit_body (body_p, fndecl);
4917 /* Make sure input_location isn't set to something wierd. */
4918 input_location = DECL_SOURCE_LOCATION (fndecl);
4920 /* Resolve callee-copies. This has to be done before processing
4921 the body so that DECL_VALUE_EXPR gets processed correctly. */
4922 parm_stmts = do_parms ? gimplify_parameters () : NULL;
4924 /* Gimplify the function's body. */
4925 gimplify_stmt (body_p);
4929 body = alloc_stmt_list ();
4930 else if (TREE_CODE (body) == STATEMENT_LIST)
4932 tree t = expr_only (*body_p);
4937 /* If there isn't an outer BIND_EXPR, add one. */
4938 if (TREE_CODE (body) != BIND_EXPR)
4940 tree b = build (BIND_EXPR, void_type_node, NULL_TREE,
4941 NULL_TREE, NULL_TREE);
4942 TREE_SIDE_EFFECTS (b) = 1;
4943 append_to_statement_list_force (body, &BIND_EXPR_BODY (b));
4947 /* If we had callee-copies statements, insert them at the beginning
4951 append_to_statement_list_force (BIND_EXPR_BODY (body), &parm_stmts);
4952 BIND_EXPR_BODY (body) = parm_stmts;
4955 /* Unshare again, in case gimplification was sloppy. */
4956 unshare_all_trees (body);
4960 pop_gimplify_context (body);
4962 #ifdef ENABLE_CHECKING
4963 walk_tree (body_p, check_pointer_types_r, NULL, NULL);
4966 timevar_pop (TV_TREE_GIMPLIFY);
4967 input_location = saved_location;
4970 /* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL
4971 node for the function we want to gimplify. */
4974 gimplify_function_tree (tree fndecl)
4976 tree oldfn, parm, ret;
4978 oldfn = current_function_decl;
4979 current_function_decl = fndecl;
4980 cfun = DECL_STRUCT_FUNCTION (fndecl);
4982 allocate_struct_function (fndecl);
4984 for (parm = DECL_ARGUMENTS (fndecl); parm ; parm = TREE_CHAIN (parm))
4986 /* Preliminarily mark non-addressed complex variables as eligible
4987 for promotion to gimple registers. We'll transform their uses
4989 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
4990 && !TREE_THIS_VOLATILE (parm)
4991 && !needs_to_live_in_memory (parm))
4992 DECL_COMPLEX_GIMPLE_REG_P (parm) = 1;
4995 ret = DECL_RESULT (fndecl);
4996 if (TREE_CODE (TREE_TYPE (ret)) == COMPLEX_TYPE
4997 && !needs_to_live_in_memory (ret))
4998 DECL_COMPLEX_GIMPLE_REG_P (ret) = 1;
5000 gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl, true);
5002 /* If we're instrumenting function entry/exit, then prepend the call to
5003 the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
5004 catch the exit hook. */
5005 /* ??? Add some way to ignore exceptions for this TFE. */
5006 if (flag_instrument_function_entry_exit
5007 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl))
5011 tf = build (TRY_FINALLY_EXPR, void_type_node, NULL, NULL);
5012 TREE_SIDE_EFFECTS (tf) = 1;
5013 x = DECL_SAVED_TREE (fndecl);
5014 append_to_statement_list (x, &TREE_OPERAND (tf, 0));
5015 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_EXIT];
5016 x = build_function_call_expr (x, NULL);
5017 append_to_statement_list (x, &TREE_OPERAND (tf, 1));
5019 bind = build (BIND_EXPR, void_type_node, NULL, NULL, NULL);
5020 TREE_SIDE_EFFECTS (bind) = 1;
5021 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_ENTER];
5022 x = build_function_call_expr (x, NULL);
5023 append_to_statement_list (x, &BIND_EXPR_BODY (bind));
5024 append_to_statement_list (tf, &BIND_EXPR_BODY (bind));
5026 DECL_SAVED_TREE (fndecl) = bind;
5029 current_function_decl = oldfn;
5030 cfun = oldfn ? DECL_STRUCT_FUNCTION (oldfn) : NULL;
5034 /* Expands EXPR to list of gimple statements STMTS. If SIMPLE is true,
5035 force the result to be either ssa_name or an invariant, otherwise
5036 just force it to be a rhs expression. If VAR is not NULL, make the
5037 base variable of the final destination be VAR if suitable. */
5040 force_gimple_operand (tree expr, tree *stmts, bool simple, tree var)
5043 enum gimplify_status ret;
5044 gimple_predicate gimple_test_f;
5048 if (is_gimple_val (expr))
5051 gimple_test_f = simple ? is_gimple_val : is_gimple_reg_rhs;
5053 push_gimplify_context ();
5054 gimplify_ctxp->into_ssa = in_ssa_p;
5057 expr = build (MODIFY_EXPR, TREE_TYPE (var), var, expr);
5059 ret = gimplify_expr (&expr, stmts, NULL,
5060 gimple_test_f, fb_rvalue);
5061 gcc_assert (ret != GS_ERROR);
5063 if (referenced_vars)
5065 for (t = gimplify_ctxp->temps; t ; t = TREE_CHAIN (t))
5066 add_referenced_tmp_var (t);
5069 pop_gimplify_context (NULL);
5074 /* Invokes force_gimple_operand for EXPR with parameters SIMPLE_P and VAR. If
5075 some statements are produced, emits them before BSI. */
5078 force_gimple_operand_bsi (block_stmt_iterator *bsi, tree expr,
5079 bool simple_p, tree var)
5083 expr = force_gimple_operand (expr, &stmts, simple_p, var);
5085 bsi_insert_before (bsi, stmts, BSI_SAME_STMT);
5090 #include "gt-gimplify.h"