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 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, 59 Temple Place - Suite 330, Boston, MA
26 #include "coretypes.h"
32 #include "tree-gimple.h"
33 #include "tree-inline.h"
34 #include "diagnostic.h"
35 #include "langhooks.h"
36 #include "langhooks-def.h"
37 #include "tree-flow.h"
50 static struct gimplify_ctx
52 tree current_bind_expr;
55 tree conditional_cleanups;
59 varray_type case_labels;
60 /* The formal temporary table. Should this be persistent? */
65 /* Formal (expression) temporary table handling: Multiple occurrences of
66 the same scalar expression are evaluated into the same temporary. */
68 typedef struct gimple_temp_hash_elt
71 tree temp; /* Value */
74 /* Forward declarations. */
75 static enum gimplify_status gimplify_compound_expr (tree *, tree *, bool);
78 /* Return a hash value for a formal temporary table entry. */
81 gimple_tree_hash (const void *p)
83 tree t = ((const elt_t *) p)->val;
84 return iterative_hash_expr (t, 0);
87 /* Compare two formal temporary table entries. */
90 gimple_tree_eq (const void *p1, const void *p2)
92 tree t1 = ((const elt_t *) p1)->val;
93 tree t2 = ((const elt_t *) p2)->val;
94 enum tree_code code = TREE_CODE (t1);
96 if (TREE_CODE (t2) != code
97 || TREE_TYPE (t1) != TREE_TYPE (t2))
100 if (!operand_equal_p (t1, t2, 0))
103 /* Only allow them to compare equal if they also hash equal; otherwise
104 results are nondeterminate, and we fail bootstrap comparison. */
105 if (gimple_tree_hash (p1) != gimple_tree_hash (p2))
111 /* Set up a context for the gimplifier. */
114 push_gimplify_context (void)
119 = (struct gimplify_ctx *) xcalloc (1, sizeof (struct gimplify_ctx));
121 gimplify_ctxp->temp_htab
122 = htab_create (1000, gimple_tree_hash, gimple_tree_eq, free);
124 gimplify_ctxp->temp_htab = NULL;
127 /* Tear down a context for the gimplifier. If BODY is non-null, then
128 put the temporaries into the outer BIND_EXPR. Otherwise, put them
129 in the unexpanded_var_list. */
132 pop_gimplify_context (tree body)
136 if (!gimplify_ctxp || gimplify_ctxp->current_bind_expr)
139 for (t = gimplify_ctxp->temps; t ; t = TREE_CHAIN (t))
140 DECL_GIMPLE_FORMAL_TEMP_P (t) = 0;
143 declare_tmp_vars (gimplify_ctxp->temps, body);
145 record_vars (gimplify_ctxp->temps);
148 if (!quiet_flag && optimize)
149 fprintf (stderr, " collisions: %f ",
150 htab_collisions (gimplify_ctxp->temp_htab));
154 htab_delete (gimplify_ctxp->temp_htab);
155 free (gimplify_ctxp);
156 gimplify_ctxp = NULL;
160 gimple_push_bind_expr (tree bind)
162 TREE_CHAIN (bind) = gimplify_ctxp->current_bind_expr;
163 gimplify_ctxp->current_bind_expr = bind;
167 gimple_pop_bind_expr (void)
169 gimplify_ctxp->current_bind_expr
170 = TREE_CHAIN (gimplify_ctxp->current_bind_expr);
174 gimple_current_bind_expr (void)
176 return gimplify_ctxp->current_bind_expr;
179 /* Returns true iff there is a COND_EXPR between us and the innermost
180 CLEANUP_POINT_EXPR. This info is used by gimple_push_cleanup. */
183 gimple_conditional_context (void)
185 return gimplify_ctxp->conditions > 0;
188 /* Note that we've entered a COND_EXPR. */
191 gimple_push_condition (void)
193 ++(gimplify_ctxp->conditions);
196 /* Note that we've left a COND_EXPR. If we're back at unconditional scope
197 now, add any conditional cleanups we've seen to the prequeue. */
200 gimple_pop_condition (tree *pre_p)
202 int conds = --(gimplify_ctxp->conditions);
206 append_to_statement_list (gimplify_ctxp->conditional_cleanups, pre_p);
207 gimplify_ctxp->conditional_cleanups = NULL_TREE;
213 /* A subroutine of append_to_statement_list{,_force}. */
216 append_to_statement_list_1 (tree t, tree *list_p, bool side_effects)
219 tree_stmt_iterator i;
226 if (t && TREE_CODE (t) == STATEMENT_LIST)
231 *list_p = list = alloc_stmt_list ();
235 tsi_link_after (&i, t, TSI_CONTINUE_LINKING);
238 /* Add T to the end of the list container pointed by LIST_P.
239 If T is an expression with no effects, it is ignored. */
242 append_to_statement_list (tree t, tree *list_p)
244 append_to_statement_list_1 (t, list_p, t ? TREE_SIDE_EFFECTS (t) : false);
247 /* Similar, but the statement is always added, regardless of side effects. */
250 append_to_statement_list_force (tree t, tree *list_p)
252 append_to_statement_list_1 (t, list_p, t != NULL);
255 /* Both gimplify the statement T and append it to LIST_P. */
258 gimplify_and_add (tree t, tree *list_p)
261 append_to_statement_list (t, list_p);
264 /* Strip off a legitimate source ending from the input string NAME of
265 length LEN. Rather than having to know the names used by all of
266 our front ends, we strip off an ending of a period followed by
267 up to five characters. (Java uses ".class".) */
270 remove_suffix (char *name, int len)
274 for (i = 2; i < 8 && len > i; i++)
276 if (name[len - i] == '.')
278 name[len - i] = '\0';
284 /* Create a nameless artificial label and put it in the current function
285 context. Returns the newly created label. */
288 create_artificial_label (void)
290 tree lab = build_decl (LABEL_DECL, NULL_TREE, void_type_node);
292 DECL_ARTIFICIAL (lab) = 1;
293 DECL_CONTEXT (lab) = current_function_decl;
297 /* Create a new temporary name with PREFIX. Returns an identifier. */
299 static GTY(()) unsigned int tmp_var_id_num;
302 create_tmp_var_name (const char *prefix)
308 char *preftmp = ASTRDUP (prefix);
310 remove_suffix (preftmp, strlen (preftmp));
314 ASM_FORMAT_PRIVATE_NAME (tmp_name, prefix ? prefix : "T", tmp_var_id_num++);
315 return get_identifier (tmp_name);
319 /* Create a new temporary variable declaration of type TYPE.
320 Does NOT push it into the current binding. */
323 create_tmp_var_raw (tree type, const char *prefix)
328 /* Make the type of the variable writable. */
329 new_type = build_type_variant (type, 0, 0);
330 TYPE_ATTRIBUTES (new_type) = TYPE_ATTRIBUTES (type);
332 tmp_var = build_decl (VAR_DECL, create_tmp_var_name (prefix), type);
334 /* The variable was declared by the compiler. */
335 DECL_ARTIFICIAL (tmp_var) = 1;
336 /* And we don't want debug info for it. */
337 DECL_IGNORED_P (tmp_var) = 1;
339 /* Make the variable writable. */
340 TREE_READONLY (tmp_var) = 0;
342 DECL_EXTERNAL (tmp_var) = 0;
343 TREE_STATIC (tmp_var) = 0;
344 TREE_USED (tmp_var) = 1;
349 /* Create a new temporary variable declaration of type TYPE. DOES push the
350 variable into the current binding. Further, assume that this is called
351 only from gimplification or optimization, at which point the creation of
352 certain types are bugs. */
355 create_tmp_var (tree type, const char *prefix)
359 #if defined ENABLE_CHECKING
360 /* We don't allow types that are addressable (meaning we can't make copies),
361 incomplete, or of variable size. */
362 if (TREE_ADDRESSABLE (type)
363 || !COMPLETE_TYPE_P (type)
364 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST)
368 tmp_var = create_tmp_var_raw (type, prefix);
369 gimple_add_tmp_var (tmp_var);
373 /* Given a tree, try to return a useful variable name that we can use
374 to prefix a temporary that is being assigned the value of the tree.
375 I.E. given <temp> = &A, return A. */
383 STRIP_NOPS (stripped_decl);
384 if (DECL_P (stripped_decl) && DECL_NAME (stripped_decl))
385 return IDENTIFIER_POINTER (DECL_NAME (stripped_decl));
388 switch (TREE_CODE (stripped_decl))
391 return get_name (TREE_OPERAND (stripped_decl, 0));
399 /* Create a temporary with a name derived from VAL. Subroutine of
400 lookup_tmp_var; nobody else should call this function. */
403 create_tmp_from_val (tree val)
405 return create_tmp_var (TREE_TYPE (val), get_name (val));
408 /* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse
409 an existing expression temporary. */
412 lookup_tmp_var (tree val, bool is_formal)
416 /* If not optimizing, never really reuse a temporary. local-alloc
417 won't allocate any variable that is used in more than one basic
418 block, which means it will go into memory, causing much extra
419 work in reload and final and poorer code generation, outweighing
420 the extra memory allocation here. */
421 if (!optimize || !is_formal || TREE_SIDE_EFFECTS (val))
422 ret = create_tmp_from_val (val);
429 slot = htab_find_slot (gimplify_ctxp->temp_htab, (void *)&elt, INSERT);
432 elt_p = xmalloc (sizeof (*elt_p));
434 elt_p->temp = ret = create_tmp_from_val (val);
435 *slot = (void *) elt_p;
439 elt_p = (elt_t *) *slot;
445 DECL_GIMPLE_FORMAL_TEMP_P (ret) = 1;
450 /* Returns a formal temporary variable initialized with VAL. PRE_P is as
451 in gimplify_expr. Only use this function if:
453 1) The value of the unfactored expression represented by VAL will not
454 change between the initialization and use of the temporary, and
455 2) The temporary will not be otherwise modified.
457 For instance, #1 means that this is inappropriate for SAVE_EXPR temps,
458 and #2 means it is inappropriate for && temps.
460 For other cases, use get_initialized_tmp_var instead. */
463 internal_get_tmp_var (tree val, tree *pre_p, tree *post_p, bool is_formal)
468 gimplify_expr (&val, pre_p, post_p, is_gimple_formal_tmp_rhs, fb_rvalue);
470 t = lookup_tmp_var (val, is_formal);
472 mod = build (MODIFY_EXPR, TREE_TYPE (t), t, val);
474 class = TREE_CODE_CLASS (TREE_CODE (val));
475 if (EXPR_HAS_LOCATION (val))
476 SET_EXPR_LOCUS (mod, EXPR_LOCUS (val));
478 SET_EXPR_LOCATION (mod, input_location);
480 /* gimplify_modify_expr might want to reduce this further. */
481 gimplify_and_add (mod, pre_p);
486 get_formal_tmp_var (tree val, tree *pre_p)
488 return internal_get_tmp_var (val, pre_p, NULL, true);
491 /* Returns a temporary variable initialized with VAL. PRE_P and POST_P
492 are as in gimplify_expr. */
495 get_initialized_tmp_var (tree val, tree *pre_p, tree *post_p)
497 return internal_get_tmp_var (val, pre_p, post_p, false);
500 /* Declares all the variables in VARS in SCOPE. */
503 declare_tmp_vars (tree vars, tree scope)
510 /* C99 mode puts the default 'return 0;' for main outside the outer
511 braces. So drill down until we find an actual scope. */
512 while (TREE_CODE (scope) == COMPOUND_EXPR)
513 scope = TREE_OPERAND (scope, 0);
515 if (TREE_CODE (scope) != BIND_EXPR)
518 temps = nreverse (last);
519 TREE_CHAIN (last) = BIND_EXPR_VARS (scope);
520 BIND_EXPR_VARS (scope) = temps;
525 gimple_add_tmp_var (tree tmp)
527 if (TREE_CHAIN (tmp) || DECL_SEEN_IN_BIND_EXPR_P (tmp))
530 DECL_CONTEXT (tmp) = current_function_decl;
531 DECL_SEEN_IN_BIND_EXPR_P (tmp) = 1;
535 TREE_CHAIN (tmp) = gimplify_ctxp->temps;
536 gimplify_ctxp->temps = tmp;
541 declare_tmp_vars (tmp, DECL_SAVED_TREE (current_function_decl));
544 /* Determines whether to assign a locus to the statement STMT. */
547 should_carry_locus_p (tree stmt)
549 /* Don't emit a line note for a label. We particularly don't want to
550 emit one for the break label, since it doesn't actually correspond
551 to the beginning of the loop/switch. */
552 if (TREE_CODE (stmt) == LABEL_EXPR)
555 /* Do not annotate empty statements, since it confuses gcov. */
556 if (!TREE_SIDE_EFFECTS (stmt))
563 annotate_one_with_locus (tree t, location_t locus)
565 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (t)))
566 && ! EXPR_HAS_LOCATION (t)
567 && should_carry_locus_p (t))
568 SET_EXPR_LOCATION (t, locus);
572 annotate_all_with_locus (tree *stmt_p, location_t locus)
574 tree_stmt_iterator i;
579 for (i = tsi_start (*stmt_p); !tsi_end_p (i); tsi_next (&i))
581 tree t = tsi_stmt (i);
583 #ifdef ENABLE_CHECKING
584 /* Assuming we've already been gimplified, we shouldn't
585 see nested chaining constructs anymore. */
586 if (TREE_CODE (t) == STATEMENT_LIST
587 || TREE_CODE (t) == COMPOUND_EXPR)
591 annotate_one_with_locus (t, locus);
595 /* Similar to copy_tree_r() but do not copy SAVE_EXPR or TARGET_EXPR nodes.
596 These nodes model computations that should only be done once. If we
597 were to unshare something like SAVE_EXPR(i++), the gimplification
598 process would create wrong code. */
601 mostly_copy_tree_r (tree *tp, int *walk_subtrees, void *data)
603 enum tree_code code = TREE_CODE (*tp);
604 /* Don't unshare types, decls, constants and SAVE_EXPR nodes. */
605 if (TREE_CODE_CLASS (code) == 't'
606 || TREE_CODE_CLASS (code) == 'd'
607 || TREE_CODE_CLASS (code) == 'c'
608 || code == SAVE_EXPR || code == TARGET_EXPR
609 /* We can't do anything sensible with a BLOCK used as an expression,
610 but we also can't abort when we see it because of non-expression
611 uses. So just avert our eyes and cross our fingers. Silly Java. */
614 else if (code == BIND_EXPR)
617 copy_tree_r (tp, walk_subtrees, data);
622 /* Callback for walk_tree to unshare most of the shared trees rooted at
623 *TP. If *TP has been visited already (i.e., TREE_VISITED (*TP) == 1),
624 then *TP is deep copied by calling copy_tree_r.
626 This unshares the same trees as copy_tree_r with the exception of
627 SAVE_EXPR nodes. These nodes model computations that should only be
628 done once. If we were to unshare something like SAVE_EXPR(i++), the
629 gimplification process would create wrong code. */
632 copy_if_shared_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
633 void *data ATTRIBUTE_UNUSED)
636 enum tree_code code = TREE_CODE (t);
638 /* Skip types, decls, and constants. But we do want to look at their
639 types and the bounds of types. Mark them as visited so we properly
640 unmark their subtrees on the unmark pass. If we've already seen them,
641 don't look down further. */
642 if (TREE_CODE_CLASS (code) == 't'
643 || TREE_CODE_CLASS (code) == 'd'
644 || TREE_CODE_CLASS (code) == 'c')
646 if (TREE_VISITED (t))
649 TREE_VISITED (t) = 1;
652 /* If this node has been visited already, unshare it and don't look
654 else if (TREE_VISITED (t))
656 walk_tree (tp, mostly_copy_tree_r, NULL, NULL);
660 /* Otherwise, mark the tree as visited and keep looking. */
662 TREE_VISITED (t) = 1;
668 unmark_visited_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
669 void *data ATTRIBUTE_UNUSED)
671 if (TREE_VISITED (*tp))
672 TREE_VISITED (*tp) = 0;
679 /* Unshare all the trees in BODY_P, a pointer into the body of FNDECL, and the
680 bodies of any nested functions if we are unsharing the entire body of
684 unshare_body (tree *body_p, tree fndecl)
686 struct cgraph_node *cgn = cgraph_node (fndecl);
688 walk_tree (body_p, copy_if_shared_r, NULL, NULL);
689 if (body_p == &DECL_SAVED_TREE (fndecl))
690 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
691 unshare_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
694 /* Likewise, but mark all trees as not visited. */
697 unvisit_body (tree *body_p, tree fndecl)
699 struct cgraph_node *cgn = cgraph_node (fndecl);
701 walk_tree (body_p, unmark_visited_r, NULL, NULL);
702 if (body_p == &DECL_SAVED_TREE (fndecl))
703 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
704 unvisit_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
707 /* Unshare T and all the trees reached from T via TREE_CHAIN. */
710 unshare_all_trees (tree t)
712 walk_tree (&t, copy_if_shared_r, NULL, NULL);
713 walk_tree (&t, unmark_visited_r, NULL, NULL);
716 /* Unconditionally make an unshared copy of EXPR. This is used when using
717 stored expressions which span multiple functions, such as BINFO_VTABLE,
718 as the normal unsharing process can't tell that they're shared. */
721 unshare_expr (tree expr)
723 walk_tree (&expr, mostly_copy_tree_r, NULL, NULL);
727 /* A terser interface for building a representation of a exception
731 gimple_build_eh_filter (tree body, tree allowed, tree failure)
735 /* FIXME should the allowed types go in TREE_TYPE? */
736 t = build (EH_FILTER_EXPR, void_type_node, allowed, NULL_TREE);
737 append_to_statement_list (failure, &EH_FILTER_FAILURE (t));
739 t = build (TRY_CATCH_EXPR, void_type_node, NULL_TREE, t);
740 append_to_statement_list (body, &TREE_OPERAND (t, 0));
746 /* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
747 contain statements and have a value. Assign its value to a temporary
748 and give it void_type_node. Returns the temporary, or NULL_TREE if
749 WRAPPER was already void. */
752 voidify_wrapper_expr (tree wrapper, tree temp)
754 if (!VOID_TYPE_P (TREE_TYPE (wrapper)))
756 tree *p, sub = wrapper;
759 /* Set p to point to the body of the wrapper. */
760 switch (TREE_CODE (sub))
763 /* For a BIND_EXPR, the body is operand 1. */
764 p = &BIND_EXPR_BODY (sub);
768 p = &TREE_OPERAND (sub, 0);
772 /* Advance to the last statement. Set all container types to void. */
773 if (TREE_CODE (*p) == STATEMENT_LIST)
775 tree_stmt_iterator i = tsi_last (*p);
776 p = tsi_end_p (i) ? NULL : tsi_stmt_ptr (i);
780 for (; TREE_CODE (*p) == COMPOUND_EXPR; p = &TREE_OPERAND (*p, 1))
782 TREE_SIDE_EFFECTS (*p) = 1;
783 TREE_TYPE (*p) = void_type_node;
787 if (p == NULL || IS_EMPTY_STMT (*p))
789 /* Look through exception handling. */
790 else if (TREE_CODE (*p) == TRY_FINALLY_EXPR
791 || TREE_CODE (*p) == TRY_CATCH_EXPR)
796 /* The C++ frontend already did this for us. */
797 else if (TREE_CODE (*p) == INIT_EXPR
798 || TREE_CODE (*p) == TARGET_EXPR)
799 temp = TREE_OPERAND (*p, 0);
800 /* If we're returning a dereference, move the dereference
801 outside the wrapper. */
802 else if (TREE_CODE (*p) == INDIRECT_REF)
804 tree ptr = TREE_OPERAND (*p, 0);
805 temp = create_tmp_var (TREE_TYPE (ptr), "retval");
806 *p = build (MODIFY_EXPR, TREE_TYPE (ptr), temp, ptr);
807 temp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (temp)), temp);
808 /* If this is a BIND_EXPR for a const inline function, it might not
809 have TREE_SIDE_EFFECTS set. That is no longer accurate. */
810 TREE_SIDE_EFFECTS (wrapper) = 1;
815 temp = create_tmp_var (TREE_TYPE (wrapper), "retval");
816 *p = build (MODIFY_EXPR, TREE_TYPE (temp), temp, *p);
817 TREE_SIDE_EFFECTS (wrapper) = 1;
820 TREE_TYPE (wrapper) = void_type_node;
827 /* Prepare calls to builtins to SAVE and RESTORE the stack as well as
828 a temporary through which they communicate. */
831 build_stack_save_restore (tree *save, tree *restore)
833 tree save_call, tmp_var;
836 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_SAVE],
838 tmp_var = create_tmp_var (ptr_type_node, "saved_stack");
840 *save = build (MODIFY_EXPR, ptr_type_node, tmp_var, save_call);
842 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_RESTORE],
843 tree_cons (NULL_TREE, tmp_var, NULL_TREE));
846 /* Gimplify a BIND_EXPR. Just voidify and recurse. */
848 static enum gimplify_status
849 gimplify_bind_expr (tree *expr_p, tree temp, tree *pre_p)
851 tree bind_expr = *expr_p;
852 bool old_save_stack = gimplify_ctxp->save_stack;
855 temp = voidify_wrapper_expr (bind_expr, temp);
857 /* Mark variables seen in this bind expr. */
858 for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t))
859 DECL_SEEN_IN_BIND_EXPR_P (t) = 1;
861 gimple_push_bind_expr (bind_expr);
862 gimplify_ctxp->save_stack = false;
864 gimplify_to_stmt_list (&BIND_EXPR_BODY (bind_expr));
866 if (gimplify_ctxp->save_stack)
868 tree stack_save, stack_restore;
870 /* Save stack on entry and restore it on exit. Add a try_finally
871 block to achieve this. Note that mudflap depends on the
872 format of the emitted code: see mx_register_decls(). */
873 build_stack_save_restore (&stack_save, &stack_restore);
875 t = build (TRY_FINALLY_EXPR, void_type_node,
876 BIND_EXPR_BODY (bind_expr), NULL_TREE);
877 append_to_statement_list (stack_restore, &TREE_OPERAND (t, 1));
879 BIND_EXPR_BODY (bind_expr) = NULL_TREE;
880 append_to_statement_list (stack_save, &BIND_EXPR_BODY (bind_expr));
881 append_to_statement_list (t, &BIND_EXPR_BODY (bind_expr));
884 gimplify_ctxp->save_stack = old_save_stack;
885 gimple_pop_bind_expr ();
890 append_to_statement_list (bind_expr, pre_p);
897 /* Gimplify a RETURN_EXPR. If the expression to be returned is not a
898 GIMPLE value, it is assigned to a new temporary and the statement is
899 re-written to return the temporary.
901 PRE_P points to the list where side effects that must happen before
902 STMT should be stored. */
904 static enum gimplify_status
905 gimplify_return_expr (tree stmt, tree *pre_p)
907 tree ret_expr = TREE_OPERAND (stmt, 0);
908 tree result_decl, result;
910 if (!ret_expr || TREE_CODE (ret_expr) == RESULT_DECL
911 || ret_expr == error_mark_node)
914 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
915 result_decl = NULL_TREE;
918 result_decl = TREE_OPERAND (ret_expr, 0);
919 if (TREE_CODE (result_decl) == INDIRECT_REF)
920 /* See through a return by reference. */
921 result_decl = TREE_OPERAND (result_decl, 0);
922 #ifdef ENABLE_CHECKING
923 if ((TREE_CODE (ret_expr) != MODIFY_EXPR
924 && TREE_CODE (ret_expr) != INIT_EXPR)
925 || TREE_CODE (result_decl) != RESULT_DECL)
930 /* If aggregate_value_p is true, then we can return the bare RESULT_DECL.
931 Recall that aggregate_value_p is FALSE for any aggregate type that is
932 returned in registers. If we're returning values in registers, then
933 we don't want to extend the lifetime of the RESULT_DECL, particularly
934 across another call. In addition, for those aggregates for which
935 hard_function_value generates a PARALLEL, we'll abort during normal
936 expansion of structure assignments; there's special code in expand_return
937 to handle this case that does not exist in expand_expr. */
939 || aggregate_value_p (result_decl, TREE_TYPE (current_function_decl)))
940 result = result_decl;
941 else if (gimplify_ctxp->return_temp)
942 result = gimplify_ctxp->return_temp;
945 result = create_tmp_var (TREE_TYPE (result_decl), NULL);
947 /* ??? With complex control flow (usually involving abnormal edges),
948 we can wind up warning about an uninitialized value for this. Due
949 to how this variable is constructed and initialized, this is never
950 true. Give up and never warn. */
951 TREE_NO_WARNING (result) = 1;
953 gimplify_ctxp->return_temp = result;
956 /* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
957 Then gimplify the whole thing. */
958 if (result != result_decl)
959 TREE_OPERAND (ret_expr, 0) = result;
961 gimplify_and_add (TREE_OPERAND (stmt, 0), pre_p);
963 /* If we didn't use a temporary, then the result is just the result_decl.
964 Otherwise we need a simple copy. This should already be gimple. */
965 if (result == result_decl)
968 ret_expr = build (MODIFY_EXPR, TREE_TYPE (result), result_decl, result);
969 TREE_OPERAND (stmt, 0) = ret_expr;
974 /* Gimplifies a DECL_EXPR node *STMT_P by making any necessary allocation
975 and initialization explicit. */
977 static enum gimplify_status
978 gimplify_decl_expr (tree *stmt_p)
981 tree decl = DECL_EXPR_DECL (stmt);
985 if (TREE_TYPE (decl) == error_mark_node)
988 else if (TREE_CODE (decl) == TYPE_DECL)
989 gimplify_type_sizes (TREE_TYPE (decl), stmt_p);
991 else if (TREE_CODE (decl) == VAR_DECL && !DECL_EXTERNAL (decl))
993 tree init = DECL_INITIAL (decl);
995 if (!TREE_CONSTANT (DECL_SIZE (decl)))
997 /* This is a variable-sized decl. Simplify its size and mark it
998 for deferred expansion. Note that mudflap depends on the format
999 of the emitted code: see mx_register_decls(). */
1000 tree t, args, addr, ptr_type;
1002 gimplify_type_sizes (TREE_TYPE (decl), stmt_p);
1003 gimplify_one_sizepos (&DECL_SIZE (decl), stmt_p);
1004 gimplify_one_sizepos (&DECL_SIZE_UNIT (decl), stmt_p);
1006 /* All occurences of this decl in final gimplified code will be
1007 replaced by indirection. Setting DECL_VALUE_EXPR does two
1008 things: First, it lets the rest of the gimplifier know what
1009 replacement to use. Second, it lets the debug info know
1010 where to find the value. */
1011 ptr_type = build_pointer_type (TREE_TYPE (decl));
1012 addr = create_tmp_var (ptr_type, get_name (decl));
1013 DECL_IGNORED_P (addr) = 0;
1014 t = build_fold_indirect_ref (addr);
1015 DECL_VALUE_EXPR (decl) = t;
1017 args = tree_cons (NULL, DECL_SIZE_UNIT (decl), NULL);
1018 t = built_in_decls[BUILT_IN_ALLOCA];
1019 t = build_function_call_expr (t, args);
1020 t = fold_convert (ptr_type, t);
1021 t = build2 (MODIFY_EXPR, void_type_node, addr, t);
1023 gimplify_and_add (t, stmt_p);
1025 /* Indicate that we need to restore the stack level when the
1026 enclosing BIND_EXPR is exited. */
1027 gimplify_ctxp->save_stack = true;
1030 if (init && init != error_mark_node)
1032 if (!TREE_STATIC (decl))
1034 DECL_INITIAL (decl) = NULL_TREE;
1035 init = build (MODIFY_EXPR, void_type_node, decl, init);
1036 gimplify_and_add (init, stmt_p);
1039 /* We must still examine initializers for static variables
1040 as they may contain a label address. */
1041 walk_tree (&init, force_labels_r, NULL, NULL);
1044 /* This decl isn't mentioned in the enclosing block, so add it to the
1045 list of temps. FIXME it seems a bit of a kludge to say that
1046 anonymous artificial vars aren't pushed, but everything else is. */
1047 if (DECL_ARTIFICIAL (decl) && DECL_NAME (decl) == NULL_TREE)
1048 gimple_add_tmp_var (decl);
1054 /* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body
1055 and replacing the LOOP_EXPR with goto, but if the loop contains an
1056 EXIT_EXPR, we need to append a label for it to jump to. */
1058 static enum gimplify_status
1059 gimplify_loop_expr (tree *expr_p, tree *pre_p)
1061 tree saved_label = gimplify_ctxp->exit_label;
1062 tree start_label = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
1063 tree jump_stmt = build_and_jump (&LABEL_EXPR_LABEL (start_label));
1065 append_to_statement_list (start_label, pre_p);
1067 gimplify_ctxp->exit_label = NULL_TREE;
1069 gimplify_and_add (LOOP_EXPR_BODY (*expr_p), pre_p);
1071 if (gimplify_ctxp->exit_label)
1073 append_to_statement_list (jump_stmt, pre_p);
1074 *expr_p = build1 (LABEL_EXPR, void_type_node, gimplify_ctxp->exit_label);
1077 *expr_p = jump_stmt;
1079 gimplify_ctxp->exit_label = saved_label;
1084 /* Compare two case labels. Because the front end should already have
1085 made sure that case ranges do not overlap, it is enough to only compare
1086 the CASE_LOW values of each case label. */
1089 compare_case_labels (const void *p1, const void *p2)
1091 tree case1 = *(tree *)p1;
1092 tree case2 = *(tree *)p2;
1094 return tree_int_cst_compare (CASE_LOW (case1), CASE_LOW (case2));
1097 /* Sort the case labels in LABEL_VEC in place in ascending order. */
1100 sort_case_labels (tree label_vec)
1102 size_t len = TREE_VEC_LENGTH (label_vec);
1103 tree default_case = TREE_VEC_ELT (label_vec, len - 1);
1105 if (CASE_LOW (default_case))
1109 /* The last label in the vector should be the default case
1111 for (i = 0; i < len; ++i)
1113 tree t = TREE_VEC_ELT (label_vec, i);
1117 TREE_VEC_ELT (label_vec, i) = TREE_VEC_ELT (label_vec, len - 1);
1118 TREE_VEC_ELT (label_vec, len - 1) = default_case;
1124 qsort (&TREE_VEC_ELT (label_vec, 0), len - 1, sizeof (tree),
1125 compare_case_labels);
1128 /* Gimplify a SWITCH_EXPR, and collect a TREE_VEC of the labels it can
1131 static enum gimplify_status
1132 gimplify_switch_expr (tree *expr_p, tree *pre_p)
1134 tree switch_expr = *expr_p;
1135 enum gimplify_status ret;
1137 ret = gimplify_expr (&SWITCH_COND (switch_expr), pre_p, NULL,
1138 is_gimple_val, fb_rvalue);
1140 if (SWITCH_BODY (switch_expr))
1142 varray_type labels, saved_labels;
1143 tree label_vec, default_case = NULL_TREE;
1146 /* If someone can be bothered to fill in the labels, they can
1147 be bothered to null out the body too. */
1148 if (SWITCH_LABELS (switch_expr))
1151 saved_labels = gimplify_ctxp->case_labels;
1152 VARRAY_TREE_INIT (gimplify_ctxp->case_labels, 8, "case_labels");
1154 gimplify_to_stmt_list (&SWITCH_BODY (switch_expr));
1156 labels = gimplify_ctxp->case_labels;
1157 gimplify_ctxp->case_labels = saved_labels;
1159 len = VARRAY_ACTIVE_SIZE (labels);
1161 for (i = 0; i < len; ++i)
1163 tree t = VARRAY_TREE (labels, i);
1166 /* The default case must be the last label in the list. */
1168 VARRAY_TREE (labels, i) = VARRAY_TREE (labels, len - 1);
1174 label_vec = make_tree_vec (len + 1);
1175 SWITCH_LABELS (*expr_p) = label_vec;
1176 append_to_statement_list (switch_expr, pre_p);
1180 /* If the switch has no default label, add one, so that we jump
1181 around the switch body. */
1182 default_case = build (CASE_LABEL_EXPR, void_type_node, NULL_TREE,
1183 NULL_TREE, create_artificial_label ());
1184 append_to_statement_list (SWITCH_BODY (switch_expr), pre_p);
1185 *expr_p = build (LABEL_EXPR, void_type_node,
1186 CASE_LABEL (default_case));
1189 *expr_p = SWITCH_BODY (switch_expr);
1191 for (i = 0; i < len; ++i)
1192 TREE_VEC_ELT (label_vec, i) = VARRAY_TREE (labels, i);
1193 TREE_VEC_ELT (label_vec, len) = default_case;
1195 sort_case_labels (label_vec);
1197 SWITCH_BODY (switch_expr) = NULL;
1199 else if (!SWITCH_LABELS (switch_expr))
1205 static enum gimplify_status
1206 gimplify_case_label_expr (tree *expr_p)
1208 tree expr = *expr_p;
1209 if (gimplify_ctxp->case_labels)
1210 VARRAY_PUSH_TREE (gimplify_ctxp->case_labels, expr);
1213 *expr_p = build (LABEL_EXPR, void_type_node, CASE_LABEL (expr));
1217 /* Gimplify a LABELED_BLOCK_EXPR into a LABEL_EXPR following
1218 a (possibly empty) body. */
1220 static enum gimplify_status
1221 gimplify_labeled_block_expr (tree *expr_p)
1223 tree body = LABELED_BLOCK_BODY (*expr_p);
1224 tree label = LABELED_BLOCK_LABEL (*expr_p);
1227 DECL_CONTEXT (label) = current_function_decl;
1228 t = build (LABEL_EXPR, void_type_node, label);
1229 if (body != NULL_TREE)
1230 t = build (COMPOUND_EXPR, void_type_node, body, t);
1236 /* Gimplify a EXIT_BLOCK_EXPR into a GOTO_EXPR. */
1238 static enum gimplify_status
1239 gimplify_exit_block_expr (tree *expr_p)
1241 tree labeled_block = TREE_OPERAND (*expr_p, 0);
1244 /* First operand must be a LABELED_BLOCK_EXPR, which should
1245 already be lowered (or partially lowered) when we get here. */
1246 #if defined ENABLE_CHECKING
1247 if (TREE_CODE (labeled_block) != LABELED_BLOCK_EXPR)
1251 label = LABELED_BLOCK_LABEL (labeled_block);
1252 *expr_p = build1 (GOTO_EXPR, void_type_node, label);
1257 /* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
1261 build_and_jump (tree *label_p)
1263 if (label_p == NULL)
1264 /* If there's nowhere to jump, just fall through. */
1267 if (*label_p == NULL_TREE)
1269 tree label = create_artificial_label ();
1273 return build1 (GOTO_EXPR, void_type_node, *label_p);
1276 /* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
1277 This also involves building a label to jump to and communicating it to
1278 gimplify_loop_expr through gimplify_ctxp->exit_label. */
1280 static enum gimplify_status
1281 gimplify_exit_expr (tree *expr_p)
1283 tree cond = TREE_OPERAND (*expr_p, 0);
1286 expr = build_and_jump (&gimplify_ctxp->exit_label);
1287 expr = build (COND_EXPR, void_type_node, cond, expr, NULL_TREE);
1293 /* A helper function to be called via walk_tree. Mark all labels under *TP
1294 as being forced. To be called for DECL_INITIAL of static variables. */
1297 force_labels_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1301 if (TREE_CODE (*tp) == LABEL_DECL)
1302 FORCED_LABEL (*tp) = 1;
1307 /* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is
1308 different from its canonical type, wrap the whole thing inside a
1309 NOP_EXPR and force the type of the COMPONENT_REF to be the canonical
1312 The canonical type of a COMPONENT_REF is the type of the field being
1313 referenced--unless the field is a bit-field which can be read directly
1314 in a smaller mode, in which case the canonical type is the
1315 sign-appropriate type corresponding to that mode. */
1318 canonicalize_component_ref (tree *expr_p)
1320 tree expr = *expr_p;
1323 if (TREE_CODE (expr) != COMPONENT_REF)
1326 if (INTEGRAL_TYPE_P (TREE_TYPE (expr)))
1327 type = TREE_TYPE (get_unwidened (expr, NULL_TREE));
1329 type = TREE_TYPE (TREE_OPERAND (expr, 1));
1331 if (TREE_TYPE (expr) != type)
1333 tree old_type = TREE_TYPE (expr);
1335 /* Set the type of the COMPONENT_REF to the underlying type. */
1336 TREE_TYPE (expr) = type;
1338 /* And wrap the whole thing inside a NOP_EXPR. */
1339 expr = build1 (NOP_EXPR, old_type, expr);
1345 /* If a NOP conversion is changing a pointer to array of foo to a pointer
1346 to foo, embed that change in the ADDR_EXPR by converting
1351 where L is the lower bound. For simplicity, only do this for constant
1355 canonicalize_addr_expr (tree *expr_p)
1357 tree expr = *expr_p;
1358 tree ctype = TREE_TYPE (expr);
1359 tree addr_expr = TREE_OPERAND (expr, 0);
1360 tree atype = TREE_TYPE (addr_expr);
1361 tree dctype, datype, ddatype, otype, obj_expr;
1363 /* Both cast and addr_expr types should be pointers. */
1364 if (!POINTER_TYPE_P (ctype) || !POINTER_TYPE_P (atype))
1367 /* The addr_expr type should be a pointer to an array. */
1368 datype = TREE_TYPE (atype);
1369 if (TREE_CODE (datype) != ARRAY_TYPE)
1372 /* Both cast and addr_expr types should address the same object type. */
1373 dctype = TREE_TYPE (ctype);
1374 ddatype = TREE_TYPE (datype);
1375 if (!lang_hooks.types_compatible_p (ddatype, dctype))
1378 /* The addr_expr and the object type should match. */
1379 obj_expr = TREE_OPERAND (addr_expr, 0);
1380 otype = TREE_TYPE (obj_expr);
1381 if (!lang_hooks.types_compatible_p (otype, datype))
1384 /* The lower bound and element sizes must be constant. */
1385 if (TREE_CODE (TYPE_SIZE_UNIT (dctype)) != INTEGER_CST
1386 || !TYPE_DOMAIN (datype) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype))
1387 || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype))) != INTEGER_CST)
1390 /* All checks succeeded. Build a new node to merge the cast. */
1391 *expr_p = build4 (ARRAY_REF, dctype, obj_expr,
1392 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1393 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1394 size_binop (EXACT_DIV_EXPR, TYPE_SIZE_UNIT (dctype),
1395 size_int (TYPE_ALIGN_UNIT (dctype))));
1396 *expr_p = build1 (ADDR_EXPR, ctype, *expr_p);
1399 /* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
1400 underneath as appropriate. */
1402 static enum gimplify_status
1403 gimplify_conversion (tree *expr_p)
1405 /* If we still have a conversion at the toplevel, then strip
1406 away all but the outermost conversion. */
1407 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1409 STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0));
1411 /* And remove the outermost conversion if it's useless. */
1412 if (tree_ssa_useless_type_conversion (*expr_p))
1413 *expr_p = TREE_OPERAND (*expr_p, 0);
1416 /* If we still have a conversion at the toplevel,
1417 then canonicalize some constructs. */
1418 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1420 tree sub = TREE_OPERAND (*expr_p, 0);
1422 /* If a NOP conversion is changing the type of a COMPONENT_REF
1423 expression, then canonicalize its type now in order to expose more
1424 redundant conversions. */
1425 if (TREE_CODE (sub) == COMPONENT_REF)
1426 canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0));
1428 /* If a NOP conversion is changing a pointer to array of foo
1429 to a pointer to foo, embed that change in the ADDR_EXPR. */
1430 else if (TREE_CODE (sub) == ADDR_EXPR)
1431 canonicalize_addr_expr (expr_p);
1437 /* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
1438 node pointed by EXPR_P.
1441 : min_lval '[' val ']'
1443 | compound_lval '[' val ']'
1444 | compound_lval '.' ID
1446 This is not part of the original SIMPLE definition, which separates
1447 array and member references, but it seems reasonable to handle them
1448 together. Also, this way we don't run into problems with union
1449 aliasing; gcc requires that for accesses through a union to alias, the
1450 union reference must be explicit, which was not always the case when we
1451 were splitting up array and member refs.
1453 PRE_P points to the list where side effects that must happen before
1454 *EXPR_P should be stored.
1456 POST_P points to the list where side effects that must happen after
1457 *EXPR_P should be stored. */
1459 static enum gimplify_status
1460 gimplify_compound_lval (tree *expr_p, tree *pre_p,
1461 tree *post_p, fallback_t fallback)
1465 enum gimplify_status ret = GS_OK, tret;
1468 /* Create a stack of the subexpressions so later we can walk them in
1469 order from inner to outer.
1471 This array is very memory consuming. Don't even think of making
1473 VARRAY_GENERIC_PTR_NOGC_INIT (stack, 10, "stack");
1475 /* We can either handle REALPART_EXPR, IMAGEPART_EXPR anything that
1476 handled_components can deal with. */
1478 (handled_component_p (*p)
1479 || TREE_CODE (*p) == REALPART_EXPR || TREE_CODE (*p) == IMAGPART_EXPR);
1480 p = &TREE_OPERAND (*p, 0))
1481 VARRAY_PUSH_GENERIC_PTR_NOGC (stack, *p);
1483 #if defined ENABLE_CHECKING
1484 if (VARRAY_ACTIVE_SIZE (stack) == 0)
1488 /* Now STACK is a stack of pointers to all the refs we've walked through
1489 and P points to the innermost expression.
1491 Java requires that we elaborated nodes in source order. That
1492 means we must gimplify the inner expression followed by each of
1493 the indices, in order. But we can't gimplify the inner
1494 expression until we deal with any variable bounds, sizes, or
1495 positions in order to deal with PLACEHOLDER_EXPRs.
1497 So we do this in three steps. First we deal with the annotations
1498 for any variables in the components, then we gimplify the base,
1499 then we gimplify any indices, from left to right. */
1500 for (i = VARRAY_ACTIVE_SIZE (stack) - 1; i >= 0; i--)
1502 tree t = VARRAY_GENERIC_PTR_NOGC (stack, i);
1504 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1506 /* Gimplify the low bound and element type size and put them into
1507 the ARRAY_REF. If these values are set, they have already been
1509 if (!TREE_OPERAND (t, 2))
1511 tree low = unshare_expr (array_ref_low_bound (t));
1512 if (!is_gimple_min_invariant (low))
1514 TREE_OPERAND (t, 2) = low;
1515 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1516 is_gimple_formal_tmp_reg, fb_rvalue);
1517 ret = MIN (ret, tret);
1521 if (!TREE_OPERAND (t, 3))
1523 tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
1524 tree elmt_size = unshare_expr (array_ref_element_size (t));
1525 tree factor = size_int (TYPE_ALIGN_UNIT (elmt_type));
1527 /* Divide the element size by the alignment of the element
1529 elmt_size = size_binop (EXACT_DIV_EXPR, elmt_size, factor);
1531 if (!is_gimple_min_invariant (elmt_size))
1533 TREE_OPERAND (t, 3) = elmt_size;
1534 tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p,
1535 is_gimple_formal_tmp_reg, fb_rvalue);
1536 ret = MIN (ret, tret);
1540 else if (TREE_CODE (t) == COMPONENT_REF)
1542 /* Set the field offset into T and gimplify it. */
1543 if (!TREE_OPERAND (t, 2))
1545 tree offset = unshare_expr (component_ref_field_offset (t));
1546 tree field = TREE_OPERAND (t, 1);
1548 = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
1550 /* Divide the offset by its alignment. */
1551 offset = size_binop (EXACT_DIV_EXPR, offset, factor);
1553 if (!is_gimple_min_invariant (offset))
1555 TREE_OPERAND (t, 2) = offset;
1556 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1557 is_gimple_formal_tmp_reg, fb_rvalue);
1558 ret = MIN (ret, tret);
1564 /* Step 2 is to gimplify the base expression. */
1565 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1566 ret = MIN (ret, tret);
1568 /* And finally, the indices and operands to BIT_FIELD_REF. During this
1569 loop we also remove any useless conversions. */
1570 for (; VARRAY_ACTIVE_SIZE (stack) > 0; )
1572 tree t = VARRAY_TOP_TREE (stack);
1574 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1576 /* Gimplify the dimension.
1577 Temporary fix for gcc.c-torture/execute/20040313-1.c.
1578 Gimplify non-constant array indices into a temporary
1580 FIXME - The real fix is to gimplify post-modify
1581 expressions into a minimal gimple lvalue. However, that
1582 exposes bugs in alias analysis. The alias analyzer does
1583 not handle &PTR->FIELD very well. Will fix after the
1584 branch is merged into mainline (dnovillo 2004-05-03). */
1585 if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
1587 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1588 is_gimple_formal_tmp_reg, fb_rvalue);
1589 ret = MIN (ret, tret);
1592 else if (TREE_CODE (t) == BIT_FIELD_REF)
1594 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1595 is_gimple_val, fb_rvalue);
1596 ret = MIN (ret, tret);
1597 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1598 is_gimple_val, fb_rvalue);
1599 ret = MIN (ret, tret);
1602 STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0));
1604 /* The innermost expression P may have originally had TREE_SIDE_EFFECTS
1605 set which would have caused all the outer expressions in EXPR_P
1606 leading to P to also have had TREE_SIDE_EFFECTS set. */
1607 recalculate_side_effects (t);
1611 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1612 ret = MIN (ret, tret);
1614 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
1615 if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF)
1617 canonicalize_component_ref (expr_p);
1618 ret = MIN (ret, GS_OK);
1621 VARRAY_FREE (stack);
1626 /* Gimplify the self modifying expression pointed by EXPR_P (++, --, +=, -=).
1628 PRE_P points to the list where side effects that must happen before
1629 *EXPR_P should be stored.
1631 POST_P points to the list where side effects that must happen after
1632 *EXPR_P should be stored.
1634 WANT_VALUE is nonzero iff we want to use the value of this expression
1635 in another expression. */
1637 static enum gimplify_status
1638 gimplify_self_mod_expr (tree *expr_p, tree *pre_p, tree *post_p,
1641 enum tree_code code;
1642 tree lhs, lvalue, rhs, t1;
1644 enum tree_code arith_code;
1645 enum gimplify_status ret;
1647 code = TREE_CODE (*expr_p);
1649 #if defined ENABLE_CHECKING
1650 if (code != POSTINCREMENT_EXPR
1651 && code != POSTDECREMENT_EXPR
1652 && code != PREINCREMENT_EXPR
1653 && code != PREDECREMENT_EXPR)
1657 /* Prefix or postfix? */
1658 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
1659 /* Faster to treat as prefix if result is not used. */
1660 postfix = want_value;
1664 /* Add or subtract? */
1665 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
1666 arith_code = PLUS_EXPR;
1668 arith_code = MINUS_EXPR;
1670 /* Gimplify the LHS into a GIMPLE lvalue. */
1671 lvalue = TREE_OPERAND (*expr_p, 0);
1672 ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
1673 if (ret == GS_ERROR)
1676 /* Extract the operands to the arithmetic operation. */
1678 rhs = TREE_OPERAND (*expr_p, 1);
1680 /* For postfix operator, we evaluate the LHS to an rvalue and then use
1681 that as the result value and in the postqueue operation. */
1684 ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
1685 if (ret == GS_ERROR)
1689 t1 = build (arith_code, TREE_TYPE (*expr_p), lhs, rhs);
1690 t1 = build (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
1694 gimplify_and_add (t1, post_p);
1705 /* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
1708 maybe_with_size_expr (tree *expr_p)
1710 tree expr = *expr_p;
1711 tree type = TREE_TYPE (expr);
1714 /* If we've already wrapped this or the type is error_mark_node, we can't do
1716 if (TREE_CODE (expr) == WITH_SIZE_EXPR
1717 || type == error_mark_node)
1720 /* If the size isn't known or is a constant, we have nothing to do. */
1721 size = TYPE_SIZE_UNIT (type);
1722 if (!size || TREE_CODE (size) == INTEGER_CST)
1725 /* Otherwise, make a WITH_SIZE_EXPR. */
1726 size = unshare_expr (size);
1727 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr);
1728 *expr_p = build2 (WITH_SIZE_EXPR, type, expr, size);
1731 /* Subroutine of gimplify_call_expr: Gimplify a single argument. */
1733 static enum gimplify_status
1734 gimplify_arg (tree *expr_p, tree *pre_p)
1736 bool (*test) (tree);
1739 /* In general, we allow lvalues for function arguments to avoid
1740 extra overhead of copying large aggregates out of even larger
1741 aggregates into temporaries only to copy the temporaries to
1742 the argument list. Make optimizers happy by pulling out to
1743 temporaries those types that fit in registers. */
1744 if (is_gimple_reg_type (TREE_TYPE (*expr_p)))
1745 test = is_gimple_val, fb = fb_rvalue;
1747 test = is_gimple_lvalue, fb = fb_either;
1749 /* If this is a variable sized type, we must remember the size. */
1750 maybe_with_size_expr (expr_p);
1752 /* There is a sequence point before a function call. Side effects in
1753 the argument list must occur before the actual call. So, when
1754 gimplifying arguments, force gimplify_expr to use an internal
1755 post queue which is then appended to the end of PRE_P. */
1756 return gimplify_expr (expr_p, pre_p, NULL, test, fb);
1759 /* Gimplify the CALL_EXPR node pointed by EXPR_P. PRE_P points to the
1760 list where side effects that must happen before *EXPR_P should be stored.
1761 WANT_VALUE is true if the result of the call is desired. */
1763 static enum gimplify_status
1764 gimplify_call_expr (tree *expr_p, tree *pre_p, bool want_value)
1768 enum gimplify_status ret;
1770 #if defined ENABLE_CHECKING
1771 if (TREE_CODE (*expr_p) != CALL_EXPR)
1775 /* For reliable diagnostics during inlining, it is necessary that
1776 every call_expr be annotated with file and line. */
1777 if (! EXPR_HAS_LOCATION (*expr_p))
1778 SET_EXPR_LOCATION (*expr_p, input_location);
1780 /* This may be a call to a builtin function.
1782 Builtin function calls may be transformed into different
1783 (and more efficient) builtin function calls under certain
1784 circumstances. Unfortunately, gimplification can muck things
1785 up enough that the builtin expanders are not aware that certain
1786 transformations are still valid.
1788 So we attempt transformation/gimplification of the call before
1789 we gimplify the CALL_EXPR. At this time we do not manage to
1790 transform all calls in the same manner as the expanders do, but
1791 we do transform most of them. */
1792 decl = get_callee_fndecl (*expr_p);
1793 if (decl && DECL_BUILT_IN (decl))
1795 tree new = simplify_builtin (*expr_p, !want_value);
1797 if (new && new != *expr_p)
1799 /* There was a transformation of this call which computes the
1800 same value, but in a more efficient way. Return and try
1806 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_VA_START)
1807 /* Avoid gimplifying the second argument to va_start, which needs
1808 to be the plain PARM_DECL. */
1809 return gimplify_arg (&TREE_VALUE (TREE_OPERAND (*expr_p, 1)), pre_p);
1812 /* There is a sequence point before the call, so any side effects in
1813 the calling expression must occur before the actual call. Force
1814 gimplify_expr to use an internal post queue. */
1815 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, NULL,
1816 is_gimple_call_addr, fb_rvalue);
1818 if (PUSH_ARGS_REVERSED)
1819 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1820 for (arglist = TREE_OPERAND (*expr_p, 1); arglist;
1821 arglist = TREE_CHAIN (arglist))
1823 enum gimplify_status t;
1825 t = gimplify_arg (&TREE_VALUE (arglist), pre_p);
1830 if (PUSH_ARGS_REVERSED)
1831 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1833 /* Try this again in case gimplification exposed something. */
1834 if (ret != GS_ERROR && decl && DECL_BUILT_IN (decl))
1836 tree new = simplify_builtin (*expr_p, !want_value);
1838 if (new && new != *expr_p)
1840 /* There was a transformation of this call which computes the
1841 same value, but in a more efficient way. Return and try
1848 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
1849 decl. This allows us to eliminate redundant or useless
1850 calls to "const" functions. */
1851 if (TREE_CODE (*expr_p) == CALL_EXPR
1852 && (call_expr_flags (*expr_p) & (ECF_CONST | ECF_PURE)))
1853 TREE_SIDE_EFFECTS (*expr_p) = 0;
1858 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
1859 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
1861 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
1862 condition is true or false, respectively. If null, we should generate
1863 our own to skip over the evaluation of this specific expression.
1865 This function is the tree equivalent of do_jump.
1867 shortcut_cond_r should only be called by shortcut_cond_expr. */
1870 shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p)
1872 tree local_label = NULL_TREE;
1873 tree t, expr = NULL;
1875 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
1876 retain the shortcut semantics. Just insert the gotos here;
1877 shortcut_cond_expr will append the real blocks later. */
1878 if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
1880 /* Turn if (a && b) into
1882 if (a); else goto no;
1883 if (b) goto yes; else goto no;
1886 if (false_label_p == NULL)
1887 false_label_p = &local_label;
1889 t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p);
1890 append_to_statement_list (t, &expr);
1892 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1894 append_to_statement_list (t, &expr);
1896 else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
1898 /* Turn if (a || b) into
1901 if (b) goto yes; else goto no;
1904 if (true_label_p == NULL)
1905 true_label_p = &local_label;
1907 t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL);
1908 append_to_statement_list (t, &expr);
1910 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1912 append_to_statement_list (t, &expr);
1914 else if (TREE_CODE (pred) == COND_EXPR)
1916 /* As long as we're messing with gotos, turn if (a ? b : c) into
1918 if (b) goto yes; else goto no;
1920 if (c) goto yes; else goto no; */
1921 expr = build (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
1922 shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1924 shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
1929 expr = build (COND_EXPR, void_type_node, pred,
1930 build_and_jump (true_label_p),
1931 build_and_jump (false_label_p));
1936 t = build1 (LABEL_EXPR, void_type_node, local_label);
1937 append_to_statement_list (t, &expr);
1944 shortcut_cond_expr (tree expr)
1946 tree pred = TREE_OPERAND (expr, 0);
1947 tree then_ = TREE_OPERAND (expr, 1);
1948 tree else_ = TREE_OPERAND (expr, 2);
1949 tree true_label, false_label, end_label, t;
1951 tree *false_label_p;
1952 bool emit_end, emit_false;
1953 bool then_se = then_ && TREE_SIDE_EFFECTS (then_);
1954 bool else_se = else_ && TREE_SIDE_EFFECTS (else_);
1956 /* First do simple transformations. */
1959 /* If there is no 'else', turn (a && b) into if (a) if (b). */
1960 while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
1962 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
1963 then_ = shortcut_cond_expr (expr);
1964 pred = TREE_OPERAND (pred, 0);
1965 expr = build (COND_EXPR, void_type_node, pred, then_, NULL_TREE);
1970 /* If there is no 'then', turn
1973 if (a); else if (b); else d. */
1974 while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
1976 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
1977 else_ = shortcut_cond_expr (expr);
1978 pred = TREE_OPERAND (pred, 0);
1979 expr = build (COND_EXPR, void_type_node, pred, NULL_TREE, else_);
1983 /* If we're done, great. */
1984 if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
1985 && TREE_CODE (pred) != TRUTH_ORIF_EXPR)
1988 /* Otherwise we need to mess with gotos. Change
1991 if (a); else goto no;
1994 and recursively gimplify the condition. */
1996 true_label = false_label = end_label = NULL_TREE;
1998 /* If our arms just jump somewhere, hijack those labels so we don't
1999 generate jumps to jumps. */
2002 && TREE_CODE (then_) == GOTO_EXPR
2003 && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
2005 true_label = GOTO_DESTINATION (then_);
2011 && TREE_CODE (else_) == GOTO_EXPR
2012 && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
2014 false_label = GOTO_DESTINATION (else_);
2019 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2021 true_label_p = &true_label;
2023 true_label_p = NULL;
2025 /* The 'else' branch also needs a label if it contains interesting code. */
2026 if (false_label || else_se)
2027 false_label_p = &false_label;
2029 false_label_p = NULL;
2031 /* If there was nothing else in our arms, just forward the label(s). */
2032 if (!then_se && !else_se)
2033 return shortcut_cond_r (pred, true_label_p, false_label_p);
2035 /* If our last subexpression already has a terminal label, reuse it. */
2037 expr = expr_last (else_);
2039 expr = expr_last (then_);
2042 if (expr && TREE_CODE (expr) == LABEL_EXPR)
2043 end_label = LABEL_EXPR_LABEL (expr);
2045 /* If we don't care about jumping to the 'else' branch, jump to the end
2046 if the condition is false. */
2048 false_label_p = &end_label;
2050 /* We only want to emit these labels if we aren't hijacking them. */
2051 emit_end = (end_label == NULL_TREE);
2052 emit_false = (false_label == NULL_TREE);
2054 pred = shortcut_cond_r (pred, true_label_p, false_label_p);
2057 append_to_statement_list (pred, &expr);
2059 append_to_statement_list (then_, &expr);
2062 t = build_and_jump (&end_label);
2063 append_to_statement_list (t, &expr);
2066 t = build1 (LABEL_EXPR, void_type_node, false_label);
2067 append_to_statement_list (t, &expr);
2069 append_to_statement_list (else_, &expr);
2071 if (emit_end && end_label)
2073 t = build1 (LABEL_EXPR, void_type_node, end_label);
2074 append_to_statement_list (t, &expr);
2080 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2083 gimple_boolify (tree expr)
2085 tree type = TREE_TYPE (expr);
2087 if (TREE_CODE (type) == BOOLEAN_TYPE)
2090 /* If this is the predicate of a COND_EXPR, it might not even be a
2092 expr = lang_hooks.truthvalue_conversion (expr);
2094 switch (TREE_CODE (expr))
2096 case TRUTH_AND_EXPR:
2098 case TRUTH_XOR_EXPR:
2099 case TRUTH_ANDIF_EXPR:
2100 case TRUTH_ORIF_EXPR:
2101 /* Also boolify the arguments of truth exprs. */
2102 TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
2105 case TRUTH_NOT_EXPR:
2106 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2109 case EQ_EXPR: case NE_EXPR:
2110 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2111 /* These expressions always produce boolean results. */
2112 TREE_TYPE (expr) = boolean_type_node;
2116 /* Other expressions that get here must have boolean values, but
2117 might need to be converted to the appropriate mode. */
2118 return convert (boolean_type_node, expr);
2122 /* Convert the conditional expression pointed by EXPR_P '(p) ? a : b;'
2131 The second form is used when *EXPR_P is of type void.
2133 TARGET is the tree for T1 above.
2135 PRE_P points to the list where side effects that must happen before
2136 *EXPR_P should be stored. */
2138 static enum gimplify_status
2139 gimplify_cond_expr (tree *expr_p, tree *pre_p, tree target)
2141 tree expr = *expr_p;
2142 tree tmp, tmp2, type;
2143 enum gimplify_status ret;
2145 type = TREE_TYPE (expr);
2147 TREE_TYPE (expr) = void_type_node;
2149 /* If this COND_EXPR has a value, copy the values into a temporary within
2151 else if (! VOID_TYPE_P (type))
2155 ret = gimplify_expr (&target, pre_p, NULL,
2156 is_gimple_min_lval, fb_lvalue);
2157 if (ret != GS_ERROR)
2160 tmp2 = unshare_expr (target);
2164 tmp2 = tmp = create_tmp_var (TREE_TYPE (expr), "iftmp");
2168 /* Build the then clause, 't1 = a;'. But don't build an assignment
2169 if this branch is void; in C++ it can be, if it's a throw. */
2170 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2171 TREE_OPERAND (expr, 1)
2172 = build (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 1));
2174 /* Build the else clause, 't1 = b;'. */
2175 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2176 TREE_OPERAND (expr, 2)
2177 = build (MODIFY_EXPR, void_type_node, tmp2, TREE_OPERAND (expr, 2));
2179 TREE_TYPE (expr) = void_type_node;
2180 recalculate_side_effects (expr);
2182 /* Move the COND_EXPR to the prequeue. */
2183 gimplify_and_add (expr, pre_p);
2189 /* Make sure the condition has BOOLEAN_TYPE. */
2190 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2192 /* Break apart && and || conditions. */
2193 if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
2194 || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
2196 expr = shortcut_cond_expr (expr);
2198 if (expr != *expr_p)
2202 /* We can't rely on gimplify_expr to re-gimplify the expanded
2203 form properly, as cleanups might cause the target labels to be
2204 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2205 set up a conditional context. */
2206 gimple_push_condition ();
2207 gimplify_stmt (expr_p);
2208 gimple_pop_condition (pre_p);
2214 /* Now do the normal gimplification. */
2215 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2216 is_gimple_condexpr, fb_rvalue);
2218 gimple_push_condition ();
2220 gimplify_to_stmt_list (&TREE_OPERAND (expr, 1));
2221 gimplify_to_stmt_list (&TREE_OPERAND (expr, 2));
2222 recalculate_side_effects (expr);
2224 gimple_pop_condition (pre_p);
2226 if (ret == GS_ERROR)
2228 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2230 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 2)))
2231 /* Rewrite "if (a); else b" to "if (!a) b" */
2233 TREE_OPERAND (expr, 0) = invert_truthvalue (TREE_OPERAND (expr, 0));
2234 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2235 is_gimple_condexpr, fb_rvalue);
2237 tmp = TREE_OPERAND (expr, 1);
2238 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 2);
2239 TREE_OPERAND (expr, 2) = tmp;
2242 /* Both arms are empty; replace the COND_EXPR with its predicate. */
2243 expr = TREE_OPERAND (expr, 0);
2249 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2250 a call to __builtin_memcpy. */
2252 static enum gimplify_status
2253 gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value)
2255 tree args, t, to, to_ptr, from;
2257 to = TREE_OPERAND (*expr_p, 0);
2258 from = TREE_OPERAND (*expr_p, 1);
2260 args = tree_cons (NULL, size, NULL);
2262 t = build_fold_addr_expr (from);
2263 args = tree_cons (NULL, t, args);
2265 to_ptr = build_fold_addr_expr (to);
2266 args = tree_cons (NULL, to_ptr, args);
2267 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
2268 t = build_function_call_expr (t, args);
2272 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2273 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2280 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2281 a call to __builtin_memset. In this case we know that the RHS is
2282 a CONSTRUCTOR with an empty element list. */
2284 static enum gimplify_status
2285 gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value)
2287 tree args, t, to, to_ptr;
2289 to = TREE_OPERAND (*expr_p, 0);
2291 args = tree_cons (NULL, size, NULL);
2293 args = tree_cons (NULL, integer_zero_node, args);
2295 to_ptr = build_fold_addr_expr (to);
2296 args = tree_cons (NULL, to_ptr, args);
2297 t = implicit_built_in_decls[BUILT_IN_MEMSET];
2298 t = build_function_call_expr (t, args);
2302 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2303 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2310 /* A subroutine of gimplify_init_ctor_preeval. Called via walk_tree,
2311 determine, cautiously, if a CONSTRUCTOR overlaps the lhs of an
2312 assignment. Returns non-null if we detect a potential overlap. */
2314 struct gimplify_init_ctor_preeval_data
2316 /* The base decl of the lhs object. May be NULL, in which case we
2317 have to assume the lhs is indirect. */
2320 /* The alias set of the lhs object. */
2325 gimplify_init_ctor_preeval_1 (tree *tp, int *walk_subtrees, void *xdata)
2327 struct gimplify_init_ctor_preeval_data *data
2328 = (struct gimplify_init_ctor_preeval_data *) xdata;
2331 /* If we find the base object, obviously we have overlap. */
2332 if (data->lhs_base_decl == t)
2335 /* If the constructor component is indirect, determine if we have a
2336 potential overlap with the lhs. The only bits of information we
2337 have to go on at this point are addressability and alias sets. */
2338 if (TREE_CODE (t) == INDIRECT_REF
2339 && (!data->lhs_base_decl || TREE_ADDRESSABLE (data->lhs_base_decl))
2340 && alias_sets_conflict_p (data->lhs_alias_set, get_alias_set (t)))
2343 if (DECL_P (t) || TYPE_P (t))
2348 /* A subroutine of gimplify_init_constructor. Pre-evaluate *EXPR_P,
2349 force values that overlap with the lhs (as described by *DATA)
2350 into temporaries. */
2353 gimplify_init_ctor_preeval (tree *expr_p, tree *pre_p, tree *post_p,
2354 struct gimplify_init_ctor_preeval_data *data)
2356 enum gimplify_status one;
2358 /* If the value is invariant, then there's nothing to pre-evaluate.
2359 But ensure it doesn't have any side-effects since a SAVE_EXPR is
2360 invariant but has side effects and might contain a reference to
2361 the object we're initializing. */
2362 if (TREE_INVARIANT (*expr_p) && !TREE_SIDE_EFFECTS (*expr_p))
2365 /* If the type has non-trivial constructors, we can't pre-evaluate. */
2366 if (TREE_ADDRESSABLE (TREE_TYPE (*expr_p)))
2369 /* Recurse for nested constructors. */
2370 if (TREE_CODE (*expr_p) == CONSTRUCTOR)
2373 for (list = CONSTRUCTOR_ELTS (*expr_p); list ; list = TREE_CHAIN (list))
2374 gimplify_init_ctor_preeval (&TREE_VALUE (list), pre_p, post_p, data);
2378 /* We can't preevaluate if the type contains a placeholder. */
2379 if (type_contains_placeholder_p (TREE_TYPE (*expr_p)))
2382 /* Gimplify the constructor element to something appropriate for the rhs
2383 of a MODIFY_EXPR. Given that we know the lhs is an aggregate, we know
2384 the gimplifier will consider this a store to memory. Doing this
2385 gimplification now means that we won't have to deal with complicated
2386 language-specific trees, nor trees like SAVE_EXPR that can induce
2387 exponential search behaviour. */
2388 one = gimplify_expr (expr_p, pre_p, post_p, is_gimple_mem_rhs, fb_rvalue);
2389 if (one == GS_ERROR)
2395 /* If we gimplified to a bare decl, we can be sure that it doesn't overlap
2396 with the lhs, since "a = { .x=a }" doesn't make sense. This will
2397 always be true for all scalars, since is_gimple_mem_rhs insists on a
2398 temporary variable for them. */
2399 if (DECL_P (*expr_p))
2402 /* If this is of variable size, we have no choice but to assume it doesn't
2403 overlap since we can't make a temporary for it. */
2404 if (!TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (*expr_p))))
2407 /* Otherwise, we must search for overlap ... */
2408 if (!walk_tree (expr_p, gimplify_init_ctor_preeval_1, data, NULL))
2411 /* ... and if found, force the value into a temporary. */
2412 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
2415 /* A subroutine of gimplify_init_constructor. Generate individual
2416 MODIFY_EXPRs for a CONSTRUCTOR. OBJECT is the LHS against which the
2417 assignments should happen. LIST is the CONSTRUCTOR_ELTS of the
2418 CONSTRUCTOR. CLEARED is true if the entire LHS object has been
2422 gimplify_init_ctor_eval (tree object, tree list, tree *pre_p, bool cleared)
2424 tree array_elt_type = NULL;
2426 if (TREE_CODE (TREE_TYPE (object)) == ARRAY_TYPE)
2427 array_elt_type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object)));
2429 for (; list; list = TREE_CHAIN (list))
2431 tree purpose, value, cref, init;
2433 purpose = TREE_PURPOSE (list);
2434 value = TREE_VALUE (list);
2436 /* NULL values are created above for gimplification errors. */
2440 if (cleared && initializer_zerop (value))
2445 /* ??? Here's to hoping the front end fills in all of the indicies,
2446 so we don't have to figure out what's missing ourselves. */
2449 /* ??? Need to handle this. */
2450 if (TREE_CODE (purpose) == RANGE_EXPR)
2453 cref = build (ARRAY_REF, array_elt_type, unshare_expr (object),
2454 purpose, NULL_TREE, NULL_TREE);
2457 cref = build (COMPONENT_REF, TREE_TYPE (purpose),
2458 unshare_expr (object), purpose, NULL_TREE);
2460 if (TREE_CODE (value) == CONSTRUCTOR)
2461 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
2465 init = build (MODIFY_EXPR, TREE_TYPE (cref), cref, value);
2466 gimplify_and_add (init, pre_p);
2471 /* A subroutine of gimplify_modify_expr. Break out elements of a
2472 CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.
2474 Note that we still need to clear any elements that don't have explicit
2475 initializers, so if not all elements are initialized we keep the
2476 original MODIFY_EXPR, we just remove all of the constructor elements. */
2478 static enum gimplify_status
2479 gimplify_init_constructor (tree *expr_p, tree *pre_p,
2480 tree *post_p, bool want_value)
2483 tree ctor = TREE_OPERAND (*expr_p, 1);
2484 tree type = TREE_TYPE (ctor);
2485 enum gimplify_status ret;
2488 if (TREE_CODE (ctor) != CONSTRUCTOR)
2489 return GS_UNHANDLED;
2491 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
2492 is_gimple_lvalue, fb_lvalue);
2493 if (ret == GS_ERROR)
2495 object = TREE_OPERAND (*expr_p, 0);
2497 elt_list = CONSTRUCTOR_ELTS (ctor);
2500 switch (TREE_CODE (type))
2504 case QUAL_UNION_TYPE:
2507 struct gimplify_init_ctor_preeval_data preeval_data;
2508 HOST_WIDE_INT num_elements, num_nonzero_elements;
2509 HOST_WIDE_INT num_nonconstant_elements;
2512 /* Aggregate types must lower constructors to initialization of
2513 individual elements. The exception is that a CONSTRUCTOR node
2514 with no elements indicates zero-initialization of the whole. */
2515 if (elt_list == NULL)
2518 categorize_ctor_elements (ctor, &num_nonzero_elements,
2519 &num_nonconstant_elements);
2521 /* If a const aggregate variable is being initialized, then it
2522 should never be a lose to promote the variable to be static. */
2523 if (num_nonconstant_elements == 0
2524 && TREE_READONLY (object)
2525 && TREE_CODE (object) == VAR_DECL)
2527 DECL_INITIAL (object) = ctor;
2528 TREE_STATIC (object) = 1;
2529 if (!DECL_NAME (object))
2530 DECL_NAME (object) = create_tmp_var_name ("C");
2531 walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL);
2533 /* ??? C++ doesn't automatically append a .<number> to the
2534 assembler name, and even when it does, it looks a FE private
2535 data structures to figure out what that number should be,
2536 which are not set for this variable. I suppose this is
2537 important for local statics for inline functions, which aren't
2538 "local" in the object file sense. So in order to get a unique
2539 TU-local symbol, we must invoke the lhd version now. */
2540 lhd_set_decl_assembler_name (object);
2542 *expr_p = NULL_TREE;
2546 /* If there are "lots" of initialized elements, and all of them
2547 are valid address constants, then the entire initializer can
2548 be dropped to memory, and then memcpy'd out. */
2549 if (num_nonconstant_elements == 0)
2551 HOST_WIDE_INT size = int_size_in_bytes (type);
2554 /* ??? We can still get unbounded array types, at least
2555 from the C++ front end. This seems wrong, but attempt
2556 to work around it for now. */
2559 size = int_size_in_bytes (TREE_TYPE (object));
2561 TREE_TYPE (ctor) = type = TREE_TYPE (object);
2564 /* Find the maximum alignment we can assume for the object. */
2565 /* ??? Make use of DECL_OFFSET_ALIGN. */
2566 if (DECL_P (object))
2567 align = DECL_ALIGN (object);
2569 align = TYPE_ALIGN (type);
2571 if (size > 0 && !can_move_by_pieces (size, align))
2573 tree new = create_tmp_var_raw (type, "C");
2575 gimple_add_tmp_var (new);
2576 TREE_STATIC (new) = 1;
2577 TREE_READONLY (new) = 1;
2578 DECL_INITIAL (new) = ctor;
2579 if (align > DECL_ALIGN (new))
2581 DECL_ALIGN (new) = align;
2582 DECL_USER_ALIGN (new) = 1;
2584 walk_tree (&DECL_INITIAL (new), force_labels_r, NULL, NULL);
2586 TREE_OPERAND (*expr_p, 1) = new;
2588 /* This is no longer an assignment of a CONSTRUCTOR, but
2589 we still may have processing to do on the LHS. So
2590 pretend we didn't do anything here to let that happen. */
2591 return GS_UNHANDLED;
2595 /* If there are "lots" of initialized elements, even discounting
2596 those that are not address constants (and thus *must* be
2597 computed at runtime), then partition the constructor into
2598 constant and non-constant parts. Block copy the constant
2599 parts in, then generate code for the non-constant parts. */
2600 /* TODO. There's code in cp/typeck.c to do this. */
2602 num_elements = count_type_elements (TREE_TYPE (ctor));
2604 /* If there are "lots" of zeros, then block clear the object first. */
2606 if (num_elements - num_nonzero_elements > CLEAR_RATIO
2607 && num_nonzero_elements < num_elements/4)
2610 /* ??? This bit ought not be needed. For any element not present
2611 in the initializer, we should simply set them to zero. Except
2612 we'd need to *find* the elements that are not present, and that
2613 requires trickery to avoid quadratic compile-time behavior in
2614 large cases or excessive memory use in small cases. */
2617 HOST_WIDE_INT len = list_length (elt_list);
2618 if (TREE_CODE (type) == ARRAY_TYPE)
2620 tree nelts = array_type_nelts (type);
2621 if (!host_integerp (nelts, 1)
2622 || tree_low_cst (nelts, 1) + 1 != len)
2625 else if (len != fields_length (type))
2631 /* Zap the CONSTRUCTOR element list, which simplifies this case.
2632 Note that we still have to gimplify, in order to handle the
2633 case of variable sized types. Avoid shared tree structures. */
2634 CONSTRUCTOR_ELTS (ctor) = NULL_TREE;
2635 object = unshare_expr (object);
2636 gimplify_stmt (expr_p);
2637 append_to_statement_list (*expr_p, pre_p);
2640 preeval_data.lhs_base_decl = get_base_address (object);
2641 if (!DECL_P (preeval_data.lhs_base_decl))
2642 preeval_data.lhs_base_decl = NULL;
2643 preeval_data.lhs_alias_set = get_alias_set (object);
2645 gimplify_init_ctor_preeval (&TREE_OPERAND (*expr_p, 1),
2646 pre_p, post_p, &preeval_data);
2647 gimplify_init_ctor_eval (object, elt_list, pre_p, cleared);
2649 *expr_p = NULL_TREE;
2657 /* Extract the real and imaginary parts out of the ctor. */
2661 r = TREE_VALUE (elt_list);
2662 elt_list = TREE_CHAIN (elt_list);
2665 i = TREE_VALUE (elt_list);
2666 if (TREE_CHAIN (elt_list))
2670 if (r == NULL || i == NULL)
2672 tree zero = convert (TREE_TYPE (type), integer_zero_node);
2679 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
2680 represent creation of a complex value. */
2681 if (TREE_CONSTANT (r) && TREE_CONSTANT (i))
2683 ctor = build_complex (type, r, i);
2684 TREE_OPERAND (*expr_p, 1) = ctor;
2688 ctor = build (COMPLEX_EXPR, type, r, i);
2689 TREE_OPERAND (*expr_p, 1) = ctor;
2690 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
2691 rhs_predicate_for (TREE_OPERAND (*expr_p, 0)),
2698 /* Go ahead and simplify constant constructors to VECTOR_CST. */
2699 if (TREE_CONSTANT (ctor))
2700 TREE_OPERAND (*expr_p, 1) = build_vector (type, elt_list);
2703 /* Vector types use CONSTRUCTOR all the way through gimple
2704 compilation as a general initializer. */
2705 for (; elt_list; elt_list = TREE_CHAIN (elt_list))
2707 enum gimplify_status tret;
2708 tret = gimplify_expr (&TREE_VALUE (elt_list), pre_p, post_p,
2709 is_gimple_val, fb_rvalue);
2710 if (tret == GS_ERROR)
2717 /* So how did we get a CONSTRUCTOR for a scalar type? */
2721 if (ret == GS_ERROR)
2723 else if (want_value)
2725 append_to_statement_list (*expr_p, pre_p);
2733 /* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs
2734 based on the code of the RHS. We loop for as long as something changes. */
2736 static enum gimplify_status
2737 gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p,
2738 tree *post_p, bool want_value)
2740 enum gimplify_status ret = GS_OK;
2742 while (ret != GS_UNHANDLED)
2743 switch (TREE_CODE (*from_p))
2747 /* If we are initializing something from a TARGET_EXPR, strip the
2748 TARGET_EXPR and initialize it directly, if possible. This can't
2749 be done if the initializer is void, since that implies that the
2750 temporary is set in some non-trivial way.
2752 ??? What about code that pulls out the temp and uses it
2753 elsewhere? I think that such code never uses the TARGET_EXPR as
2754 an initializer. If I'm wrong, we'll abort because the temp won't
2755 have any RTL. In that case, I guess we'll need to replace
2756 references somehow. */
2757 tree init = TARGET_EXPR_INITIAL (*from_p);
2759 if (!VOID_TYPE_P (TREE_TYPE (init)))
2770 /* Remove any COMPOUND_EXPR in the RHS so the following cases will be
2772 gimplify_compound_expr (from_p, pre_p, true);
2777 /* If we're initializing from a CONSTRUCTOR, break this into
2778 individual MODIFY_EXPRs. */
2779 return gimplify_init_constructor (expr_p, pre_p, post_p, want_value);
2782 /* If we're assigning to a non-register type, push the assignment
2783 down into the branches. This is mandatory for ADDRESSABLE types,
2784 since we cannot generate temporaries for such, but it saves a
2785 copy in other cases as well. */
2786 if (!is_gimple_reg_type (TREE_TYPE (*from_p)))
2789 return gimplify_cond_expr (expr_p, pre_p, *to_p);
2803 /* Gimplify the MODIFY_EXPR node pointed by EXPR_P.
2809 PRE_P points to the list where side effects that must happen before
2810 *EXPR_P should be stored.
2812 POST_P points to the list where side effects that must happen after
2813 *EXPR_P should be stored.
2815 WANT_VALUE is nonzero iff we want to use the value of this expression
2816 in another expression. */
2818 static enum gimplify_status
2819 gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value)
2821 tree *from_p = &TREE_OPERAND (*expr_p, 1);
2822 tree *to_p = &TREE_OPERAND (*expr_p, 0);
2823 enum gimplify_status ret = GS_UNHANDLED;
2825 #if defined ENABLE_CHECKING
2826 if (TREE_CODE (*expr_p) != MODIFY_EXPR && TREE_CODE (*expr_p) != INIT_EXPR)
2830 /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer useful. */
2831 if (TREE_CODE (*expr_p) == INIT_EXPR)
2832 TREE_SET_CODE (*expr_p, MODIFY_EXPR);
2834 /* See if any simplifications can be done based on what the RHS is. */
2835 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2837 if (ret != GS_UNHANDLED)
2840 /* If the value being copied is of variable width, compute the length
2841 of the copy into a WITH_SIZE_EXPR. Note that we need to do this
2842 before gimplifying any of the operands so that we can resolve any
2843 PLACEHOLDER_EXPRs in the size. Also note that the RTL expander uses
2844 the size of the expression to be copied, not of the destination, so
2845 that is what we must here. */
2846 maybe_with_size_expr (from_p);
2848 ret = gimplify_expr (to_p, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
2849 if (ret == GS_ERROR)
2852 ret = gimplify_expr (from_p, pre_p, post_p,
2853 rhs_predicate_for (*to_p), fb_rvalue);
2854 if (ret == GS_ERROR)
2857 /* Now see if the above changed *from_p to something we handle specially. */
2858 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2860 if (ret != GS_UNHANDLED)
2863 /* If we've got a variable sized assignment between two lvalues (i.e. does
2864 not involve a call), then we can make things a bit more straightforward
2865 by converting the assignment to memcpy or memset. */
2866 if (TREE_CODE (*from_p) == WITH_SIZE_EXPR)
2868 tree from = TREE_OPERAND (*from_p, 0);
2869 tree size = TREE_OPERAND (*from_p, 1);
2871 if (TREE_CODE (from) == CONSTRUCTOR)
2872 return gimplify_modify_expr_to_memset (expr_p, size, want_value);
2873 if (is_gimple_addressable (from))
2876 return gimplify_modify_expr_to_memcpy (expr_p, size, want_value);
2882 append_to_statement_list (*expr_p, pre_p);
2890 /* Gimplify a comparison between two variable-sized objects. Do this
2891 with a call to BUILT_IN_MEMCMP. */
2893 static enum gimplify_status
2894 gimplify_variable_sized_compare (tree *expr_p)
2896 tree op0 = TREE_OPERAND (*expr_p, 0);
2897 tree op1 = TREE_OPERAND (*expr_p, 1);
2900 t = TYPE_SIZE_UNIT (TREE_TYPE (op0));
2901 t = unshare_expr (t);
2902 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, op0);
2903 args = tree_cons (NULL, t, NULL);
2904 t = build_fold_addr_expr (op1);
2905 args = tree_cons (NULL, t, args);
2906 dest = build_fold_addr_expr (op0);
2907 args = tree_cons (NULL, dest, args);
2908 t = implicit_built_in_decls[BUILT_IN_MEMCMP];
2909 t = build_function_call_expr (t, args);
2911 = build (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), t, integer_zero_node);
2916 /* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P
2917 points to the expression to gimplify.
2919 Expressions of the form 'a && b' are gimplified to:
2921 a && b ? true : false
2923 gimplify_cond_expr will do the rest.
2925 PRE_P points to the list where side effects that must happen before
2926 *EXPR_P should be stored. */
2928 static enum gimplify_status
2929 gimplify_boolean_expr (tree *expr_p)
2931 /* Preserve the original type of the expression. */
2932 tree type = TREE_TYPE (*expr_p);
2934 *expr_p = build (COND_EXPR, type, *expr_p,
2935 convert (type, boolean_true_node),
2936 convert (type, boolean_false_node));
2941 /* Gimplifies an expression sequence. This function gimplifies each
2942 expression and re-writes the original expression with the last
2943 expression of the sequence in GIMPLE form.
2945 PRE_P points to the list where the side effects for all the
2946 expressions in the sequence will be emitted.
2948 WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */
2949 /* ??? Should rearrange to share the pre-queue with all the indirect
2950 invocations of gimplify_expr. Would probably save on creations
2951 of statement_list nodes. */
2953 static enum gimplify_status
2954 gimplify_compound_expr (tree *expr_p, tree *pre_p, bool want_value)
2960 tree *sub_p = &TREE_OPERAND (t, 0);
2962 if (TREE_CODE (*sub_p) == COMPOUND_EXPR)
2963 gimplify_compound_expr (sub_p, pre_p, false);
2965 gimplify_stmt (sub_p);
2966 append_to_statement_list (*sub_p, pre_p);
2968 t = TREE_OPERAND (t, 1);
2970 while (TREE_CODE (t) == COMPOUND_EXPR);
2977 gimplify_stmt (expr_p);
2982 /* Gimplifies a statement list. These may be created either by an
2983 enlightened front-end, or by shortcut_cond_expr. */
2985 static enum gimplify_status
2986 gimplify_statement_list (tree *expr_p)
2988 tree_stmt_iterator i = tsi_start (*expr_p);
2990 while (!tsi_end_p (i))
2994 gimplify_stmt (tsi_stmt_ptr (i));
2999 else if (TREE_CODE (t) == STATEMENT_LIST)
3001 tsi_link_before (&i, t, TSI_SAME_STMT);
3011 /* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to
3012 gimplify. After gimplification, EXPR_P will point to a new temporary
3013 that holds the original value of the SAVE_EXPR node.
3015 PRE_P points to the list where side effects that must happen before
3016 *EXPR_P should be stored. */
3018 static enum gimplify_status
3019 gimplify_save_expr (tree *expr_p, tree *pre_p, tree *post_p)
3021 enum gimplify_status ret = GS_ALL_DONE;
3024 #if defined ENABLE_CHECKING
3025 if (TREE_CODE (*expr_p) != SAVE_EXPR)
3029 val = TREE_OPERAND (*expr_p, 0);
3031 /* If the SAVE_EXPR has not been resolved, then evaluate it once. */
3032 if (!SAVE_EXPR_RESOLVED_P (*expr_p))
3034 /* The operand may be a void-valued expression such as SAVE_EXPRs
3035 generated by the Java frontend for class initialization. It is
3036 being executed only for its side-effects. */
3037 if (TREE_TYPE (val) == void_type_node)
3039 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3040 is_gimple_stmt, fb_none);
3041 append_to_statement_list (TREE_OPERAND (*expr_p, 0), pre_p);
3045 val = get_initialized_tmp_var (val, pre_p, post_p);
3047 TREE_OPERAND (*expr_p, 0) = val;
3048 SAVE_EXPR_RESOLVED_P (*expr_p) = 1;
3056 /* Re-write the ADDR_EXPR node pointed by EXPR_P
3063 PRE_P points to the list where side effects that must happen before
3064 *EXPR_P should be stored.
3066 POST_P points to the list where side effects that must happen after
3067 *EXPR_P should be stored. */
3069 static enum gimplify_status
3070 gimplify_addr_expr (tree *expr_p, tree *pre_p, tree *post_p)
3072 tree expr = *expr_p;
3073 tree op0 = TREE_OPERAND (expr, 0);
3074 enum gimplify_status ret;
3076 switch (TREE_CODE (op0))
3079 /* Check if we are dealing with an expression of the form '&*ptr'.
3080 While the front end folds away '&*ptr' into 'ptr', these
3081 expressions may be generated internally by the compiler (e.g.,
3082 builtins like __builtin_va_end). */
3083 *expr_p = TREE_OPERAND (op0, 0);
3087 case VIEW_CONVERT_EXPR:
3088 /* Take the address of our operand and then convert it to the type of
3091 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3092 all clear. The impact of this transformation is even less clear. */
3093 *expr_p = fold_convert (TREE_TYPE (expr),
3094 build_fold_addr_expr (TREE_OPERAND (op0, 0)));
3099 /* We use fb_either here because the C frontend sometimes takes
3100 the address of a call that returns a struct; see
3101 gcc.dg/c99-array-lval-1.c. The gimplifier will correctly make
3102 the implied temporary explicit. */
3103 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, post_p,
3104 is_gimple_addressable, fb_either);
3105 if (ret != GS_ERROR)
3107 /* The above may have made an INDIRECT_REF (e.g, Ada's NULL_EXPR),
3108 so check for it here. It's not worth checking for the other
3110 if (TREE_CODE (TREE_OPERAND (expr, 0)) == INDIRECT_REF)
3112 *expr_p = TREE_OPERAND (TREE_OPERAND (expr, 0), 0);
3116 /* Make sure TREE_INVARIANT, TREE_CONSTANT, and TREE_SIDE_EFFECTS
3118 recompute_tree_invarant_for_addr_expr (expr);
3120 /* Mark the RHS addressable. */
3121 lang_hooks.mark_addressable (TREE_OPERAND (expr, 0));
3129 /* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple
3130 value; output operands should be a gimple lvalue. */
3132 static enum gimplify_status
3133 gimplify_asm_expr (tree *expr_p, tree *pre_p, tree *post_p)
3135 tree expr = *expr_p;
3136 int noutputs = list_length (ASM_OUTPUTS (expr));
3137 const char **oconstraints
3138 = (const char **) alloca ((noutputs) * sizeof (const char *));
3141 const char *constraint;
3142 bool allows_mem, allows_reg, is_inout;
3143 enum gimplify_status ret, tret;
3146 = resolve_asm_operand_names (ASM_STRING (expr), ASM_OUTPUTS (expr),
3150 for (i = 0, link = ASM_OUTPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3152 oconstraints[i] = constraint
3153 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3155 parse_output_constraint (&constraint, i, 0, 0,
3156 &allows_mem, &allows_reg, &is_inout);
3158 if (!allows_reg && allows_mem)
3159 lang_hooks.mark_addressable (TREE_VALUE (link));
3161 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3162 is_inout ? is_gimple_min_lval : is_gimple_lvalue,
3163 fb_lvalue | fb_mayfail);
3164 if (tret == GS_ERROR)
3166 error ("invalid lvalue in asm output %d", i);
3172 /* An input/output operand. To give the optimizers more
3173 flexibility, split it into separate input and output
3177 size_t constraint_len = strlen (constraint);
3179 /* Turn the in/out constraint into an output constraint. */
3180 char *p = xstrdup (constraint);
3182 TREE_VALUE (TREE_PURPOSE (link)) = build_string (constraint_len, p);
3185 /* And add a matching input constraint. */
3188 sprintf (buf, "%d", i);
3189 input = build_string (strlen (buf), buf);
3192 input = build_string (constraint_len - 1, constraint + 1);
3193 input = build_tree_list (build_tree_list (NULL_TREE, input),
3194 unshare_expr (TREE_VALUE (link)));
3195 ASM_INPUTS (expr) = chainon (ASM_INPUTS (expr), input);
3199 for (link = ASM_INPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3202 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3203 parse_input_constraint (&constraint, 0, 0, noutputs, 0,
3204 oconstraints, &allows_mem, &allows_reg);
3206 /* If the operand is a memory input, it should be an lvalue. */
3207 if (!allows_reg && allows_mem)
3209 lang_hooks.mark_addressable (TREE_VALUE (link));
3210 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3211 is_gimple_lvalue, fb_lvalue | fb_mayfail);
3212 if (tret == GS_ERROR)
3214 error ("memory input %d is not directly addressable", i);
3220 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3221 is_gimple_val, fb_rvalue);
3222 if (tret == GS_ERROR)
3230 /* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding
3231 WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
3232 gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
3233 return to this function.
3235 FIXME should we complexify the prequeue handling instead? Or use flags
3236 for all the cleanups and let the optimizer tighten them up? The current
3237 code seems pretty fragile; it will break on a cleanup within any
3238 non-conditional nesting. But any such nesting would be broken, anyway;
3239 we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
3240 and continues out of it. We can do that at the RTL level, though, so
3241 having an optimizer to tighten up try/finally regions would be a Good
3244 static enum gimplify_status
3245 gimplify_cleanup_point_expr (tree *expr_p, tree *pre_p)
3247 tree_stmt_iterator iter;
3250 tree temp = voidify_wrapper_expr (*expr_p, NULL);
3252 /* We only care about the number of conditions between the innermost
3253 CLEANUP_POINT_EXPR and the cleanup. So save and reset the count. */
3254 int old_conds = gimplify_ctxp->conditions;
3255 gimplify_ctxp->conditions = 0;
3257 body = TREE_OPERAND (*expr_p, 0);
3258 gimplify_to_stmt_list (&body);
3260 gimplify_ctxp->conditions = old_conds;
3262 for (iter = tsi_start (body); !tsi_end_p (iter); )
3264 tree *wce_p = tsi_stmt_ptr (iter);
3267 if (TREE_CODE (wce) == WITH_CLEANUP_EXPR)
3269 if (tsi_one_before_end_p (iter))
3271 tsi_link_before (&iter, TREE_OPERAND (wce, 0), TSI_SAME_STMT);
3278 enum tree_code code;
3280 if (CLEANUP_EH_ONLY (wce))
3281 code = TRY_CATCH_EXPR;
3283 code = TRY_FINALLY_EXPR;
3285 sl = tsi_split_statement_list_after (&iter);
3286 tfe = build (code, void_type_node, sl, NULL_TREE);
3287 append_to_statement_list (TREE_OPERAND (wce, 0),
3288 &TREE_OPERAND (tfe, 1));
3290 iter = tsi_start (sl);
3300 append_to_statement_list (body, pre_p);
3310 /* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP
3311 is the cleanup action required. */
3314 gimple_push_cleanup (tree var, tree cleanup, bool eh_only, tree *pre_p)
3318 /* Errors can result in improperly nested cleanups. Which results in
3319 confusion when trying to resolve the WITH_CLEANUP_EXPR. */
3320 if (errorcount || sorrycount)
3323 if (gimple_conditional_context ())
3325 /* If we're in a conditional context, this is more complex. We only
3326 want to run the cleanup if we actually ran the initialization that
3327 necessitates it, but we want to run it after the end of the
3328 conditional context. So we wrap the try/finally around the
3329 condition and use a flag to determine whether or not to actually
3330 run the destructor. Thus
3334 becomes (approximately)
3338 if (test) { A::A(temp); flag = 1; val = f(temp); }
3341 if (flag) A::~A(temp);
3346 tree flag = create_tmp_var (boolean_type_node, "cleanup");
3347 tree ffalse = build (MODIFY_EXPR, void_type_node, flag,
3348 boolean_false_node);
3349 tree ftrue = build (MODIFY_EXPR, void_type_node, flag,
3351 cleanup = build (COND_EXPR, void_type_node, flag, cleanup, NULL);
3352 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3353 append_to_statement_list (ffalse, &gimplify_ctxp->conditional_cleanups);
3354 append_to_statement_list (wce, &gimplify_ctxp->conditional_cleanups);
3355 append_to_statement_list (ftrue, pre_p);
3357 /* Because of this manipulation, and the EH edges that jump
3358 threading cannot redirect, the temporary (VAR) will appear
3359 to be used uninitialized. Don't warn. */
3360 TREE_NO_WARNING (var) = 1;
3364 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3365 CLEANUP_EH_ONLY (wce) = eh_only;
3366 append_to_statement_list (wce, pre_p);
3369 gimplify_stmt (&TREE_OPERAND (wce, 0));
3372 /* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */
3374 static enum gimplify_status
3375 gimplify_target_expr (tree *expr_p, tree *pre_p, tree *post_p)
3377 tree targ = *expr_p;
3378 tree temp = TARGET_EXPR_SLOT (targ);
3379 tree init = TARGET_EXPR_INITIAL (targ);
3380 enum gimplify_status ret;
3384 /* TARGET_EXPR temps aren't part of the enclosing block, so add it
3385 to the temps list. */
3386 gimple_add_tmp_var (temp);
3388 /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
3389 expression is supposed to initialize the slot. */
3390 if (VOID_TYPE_P (TREE_TYPE (init)))
3391 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, fb_none);
3394 /* Special handling for BIND_EXPR can result in fewer temps. */
3396 if (TREE_CODE (init) == BIND_EXPR)
3397 gimplify_bind_expr (&init, temp, pre_p);
3400 init = build (MODIFY_EXPR, void_type_node, temp, init);
3401 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt,
3405 if (ret == GS_ERROR)
3407 append_to_statement_list (init, pre_p);
3409 /* If needed, push the cleanup for the temp. */
3410 if (TARGET_EXPR_CLEANUP (targ))
3412 gimplify_stmt (&TARGET_EXPR_CLEANUP (targ));
3413 gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ),
3414 CLEANUP_EH_ONLY (targ), pre_p);
3417 /* Only expand this once. */
3418 TREE_OPERAND (targ, 3) = init;
3419 TARGET_EXPR_INITIAL (targ) = NULL_TREE;
3421 else if (!DECL_SEEN_IN_BIND_EXPR_P (temp))
3422 /* We should have expanded this before. */
3429 /* Gimplification of expression trees. */
3431 /* Gimplify an expression which appears at statement context; usually, this
3432 means replacing it with a suitably gimple STATEMENT_LIST. */
3435 gimplify_stmt (tree *stmt_p)
3437 gimplify_expr (stmt_p, NULL, NULL, is_gimple_stmt, fb_none);
3440 /* Similarly, but force the result to be a STATEMENT_LIST. */
3443 gimplify_to_stmt_list (tree *stmt_p)
3445 gimplify_stmt (stmt_p);
3447 *stmt_p = alloc_stmt_list ();
3448 else if (TREE_CODE (*stmt_p) != STATEMENT_LIST)
3451 *stmt_p = alloc_stmt_list ();
3452 append_to_statement_list (t, stmt_p);
3457 /* Gimplifies the expression tree pointed by EXPR_P. Return 0 if
3458 gimplification failed.
3460 PRE_P points to the list where side effects that must happen before
3461 EXPR should be stored.
3463 POST_P points to the list where side effects that must happen after
3464 EXPR should be stored, or NULL if there is no suitable list. In
3465 that case, we copy the result to a temporary, emit the
3466 post-effects, and then return the temporary.
3468 GIMPLE_TEST_F points to a function that takes a tree T and
3469 returns nonzero if T is in the GIMPLE form requested by the
3470 caller. The GIMPLE predicates are in tree-gimple.c.
3472 This test is used twice. Before gimplification, the test is
3473 invoked to determine whether *EXPR_P is already gimple enough. If
3474 that fails, *EXPR_P is gimplified according to its code and
3475 GIMPLE_TEST_F is called again. If the test still fails, then a new
3476 temporary variable is created and assigned the value of the
3477 gimplified expression.
3479 FALLBACK tells the function what sort of a temporary we want. If the 1
3480 bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK.
3481 If both are set, either is OK, but an lvalue is preferable.
3483 The return value is either GS_ERROR or GS_ALL_DONE, since this function
3484 iterates until solution. */
3486 enum gimplify_status
3487 gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
3488 bool (* gimple_test_f) (tree), fallback_t fallback)
3491 tree internal_pre = NULL_TREE;
3492 tree internal_post = NULL_TREE;
3494 int is_statement = (pre_p == NULL);
3495 location_t saved_location;
3496 enum gimplify_status ret;
3498 save_expr = *expr_p;
3499 if (save_expr == NULL_TREE)
3502 /* We used to check the predicate here and return immediately if it
3503 succeeds. This is wrong; the design is for gimplification to be
3504 idempotent, and for the predicates to only test for valid forms, not
3505 whether they are fully simplified. */
3507 /* Set up our internal queues if needed. */
3509 pre_p = &internal_pre;
3511 post_p = &internal_post;
3513 saved_location = input_location;
3514 if (save_expr != error_mark_node
3515 && EXPR_HAS_LOCATION (*expr_p))
3516 input_location = EXPR_LOCATION (*expr_p);
3518 /* Loop over the specific gimplifiers until the toplevel node
3519 remains the same. */
3522 /* Strip away as many useless type conversions as possible
3524 STRIP_USELESS_TYPE_CONVERSION (*expr_p);
3526 /* Remember the expr. */
3527 save_expr = *expr_p;
3529 /* Die, die, die, my darling. */
3530 if (save_expr == error_mark_node
3531 || (TREE_TYPE (save_expr)
3532 && TREE_TYPE (save_expr) == error_mark_node))
3538 /* Do any language-specific gimplification. */
3539 ret = lang_hooks.gimplify_expr (expr_p, pre_p, post_p);
3542 if (*expr_p == NULL_TREE)
3544 if (*expr_p != save_expr)
3547 else if (ret != GS_UNHANDLED)
3551 switch (TREE_CODE (*expr_p))
3553 /* First deal with the special cases. */
3555 case POSTINCREMENT_EXPR:
3556 case POSTDECREMENT_EXPR:
3557 case PREINCREMENT_EXPR:
3558 case PREDECREMENT_EXPR:
3559 ret = gimplify_self_mod_expr (expr_p, pre_p, post_p,
3560 fallback != fb_none);
3564 case ARRAY_RANGE_REF:
3568 case VIEW_CONVERT_EXPR:
3569 ret = gimplify_compound_lval (expr_p, pre_p, post_p,
3570 fallback ? fallback : fb_rvalue);
3574 ret = gimplify_cond_expr (expr_p, pre_p, NULL_TREE);
3578 ret = gimplify_call_expr (expr_p, pre_p, fallback != fb_none);
3585 ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none);
3590 ret = gimplify_modify_expr (expr_p, pre_p, post_p,
3591 fallback != fb_none);
3594 case TRUTH_ANDIF_EXPR:
3595 case TRUTH_ORIF_EXPR:
3596 ret = gimplify_boolean_expr (expr_p);
3599 case TRUTH_NOT_EXPR:
3600 TREE_OPERAND (*expr_p, 0)
3601 = gimple_boolify (TREE_OPERAND (*expr_p, 0));
3602 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3603 is_gimple_val, fb_rvalue);
3604 recalculate_side_effects (*expr_p);
3608 ret = gimplify_addr_expr (expr_p, pre_p, post_p);
3612 ret = gimplify_va_arg_expr (expr_p, pre_p, post_p);
3617 if (IS_EMPTY_STMT (*expr_p))
3623 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
3624 || fallback == fb_none)
3626 /* Just strip a conversion to void (or in void context) and
3628 *expr_p = TREE_OPERAND (*expr_p, 0);
3632 ret = gimplify_conversion (expr_p);
3633 if (ret == GS_ERROR)
3635 if (*expr_p != save_expr)
3639 case FIX_TRUNC_EXPR:
3641 case FIX_FLOOR_EXPR:
3642 case FIX_ROUND_EXPR:
3643 /* unary_expr: ... | '(' cast ')' val | ... */
3644 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3645 is_gimple_val, fb_rvalue);
3646 recalculate_side_effects (*expr_p);
3650 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3651 is_gimple_reg, fb_rvalue);
3652 recalculate_side_effects (*expr_p);
3655 /* Constants need not be gimplified. */
3665 /* If we require an lvalue, such as for ADDR_EXPR, retain the
3666 CONST_DECL node. Otherwise the decl is replacable by its
3668 /* ??? Should be == fb_lvalue, but ADDR_EXPR passes fb_either. */
3669 if (fallback & fb_lvalue)
3672 *expr_p = DECL_INITIAL (*expr_p);
3676 ret = gimplify_decl_expr (expr_p);
3680 /* FIXME make this a decl. */
3685 ret = gimplify_bind_expr (expr_p, NULL, pre_p);
3689 ret = gimplify_loop_expr (expr_p, pre_p);
3693 ret = gimplify_switch_expr (expr_p, pre_p);
3696 case LABELED_BLOCK_EXPR:
3697 ret = gimplify_labeled_block_expr (expr_p);
3700 case EXIT_BLOCK_EXPR:
3701 ret = gimplify_exit_block_expr (expr_p);
3705 ret = gimplify_exit_expr (expr_p);
3709 /* If the target is not LABEL, then it is a computed jump
3710 and the target needs to be gimplified. */
3711 if (TREE_CODE (GOTO_DESTINATION (*expr_p)) != LABEL_DECL)
3712 ret = gimplify_expr (&GOTO_DESTINATION (*expr_p), pre_p,
3713 NULL, is_gimple_val, fb_rvalue);
3718 #ifdef ENABLE_CHECKING
3719 if (decl_function_context (LABEL_EXPR_LABEL (*expr_p)) != current_function_decl)
3724 case CASE_LABEL_EXPR:
3725 ret = gimplify_case_label_expr (expr_p);
3729 ret = gimplify_return_expr (*expr_p, pre_p);
3733 /* Don't reduce this in place; let gimplify_init_constructor work its
3734 magic. Buf if we're just elaborating this for side effects, just
3735 gimplify any element that has side-effects. */
3736 if (fallback == fb_none)
3738 for (tmp = CONSTRUCTOR_ELTS (*expr_p); tmp;
3739 tmp = TREE_CHAIN (tmp))
3740 if (TREE_SIDE_EFFECTS (TREE_VALUE (tmp)))
3741 gimplify_expr (&TREE_VALUE (tmp), pre_p, post_p,
3742 gimple_test_f, fallback);
3744 *expr_p = NULL_TREE;
3750 /* The following are special cases that are not handled by the
3751 original GIMPLE grammar. */
3753 /* SAVE_EXPR nodes are converted into a GIMPLE identifier and
3756 ret = gimplify_save_expr (expr_p, pre_p, post_p);
3761 enum gimplify_status r0, r1, r2;
3763 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3764 is_gimple_lvalue, fb_either);
3765 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3766 is_gimple_val, fb_rvalue);
3767 r2 = gimplify_expr (&TREE_OPERAND (*expr_p, 2), pre_p, post_p,
3768 is_gimple_val, fb_rvalue);
3769 recalculate_side_effects (*expr_p);
3771 ret = MIN (r0, MIN (r1, r2));
3775 case NON_LVALUE_EXPR:
3776 /* This should have been stripped above. */
3781 ret = gimplify_asm_expr (expr_p, pre_p, post_p);
3784 case TRY_FINALLY_EXPR:
3785 case TRY_CATCH_EXPR:
3786 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 0));
3787 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 1));
3791 case CLEANUP_POINT_EXPR:
3792 ret = gimplify_cleanup_point_expr (expr_p, pre_p);
3796 ret = gimplify_target_expr (expr_p, pre_p, post_p);
3800 gimplify_to_stmt_list (&CATCH_BODY (*expr_p));
3804 case EH_FILTER_EXPR:
3805 gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p));
3811 enum gimplify_status r0, r1;
3812 r0 = gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p), pre_p, post_p,
3813 is_gimple_val, fb_rvalue);
3814 r1 = gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p), pre_p, post_p,
3815 is_gimple_val, fb_rvalue);
3821 /* We get here when taking the address of a label. We mark
3822 the label as "forced"; meaning it can never be removed and
3823 it is a potential target for any computed goto. */
3824 FORCED_LABEL (*expr_p) = 1;
3828 case STATEMENT_LIST:
3829 ret = gimplify_statement_list (expr_p);
3832 case WITH_SIZE_EXPR:
3834 enum gimplify_status r0, r1;
3835 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3836 post_p == &internal_post ? NULL : post_p,
3837 gimple_test_f, fallback);
3838 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3839 is_gimple_val, fb_rvalue);
3844 /* ??? If this is a local variable, and it has not been seen in any
3845 outer BIND_EXPR, then it's probably the result of a duplicate
3846 declaration, for which we've already issued an error. It would
3847 be really nice if the front end wouldn't leak these at all.
3848 Currently the only known culprit is C++ destructors, as seen
3849 in g++.old-deja/g++.jason/binding.C. */
3851 if (!TREE_STATIC (tmp) && !DECL_EXTERNAL (tmp)
3852 && decl_function_context (tmp) == current_function_decl
3853 && !DECL_SEEN_IN_BIND_EXPR_P (tmp))
3855 #ifdef ENABLE_CHECKING
3856 if (!errorcount && !sorrycount)
3863 /* If this is a local variable sized decl, it must be accessed
3864 indirectly. Perform that substitution. */
3865 if (DECL_VALUE_EXPR (tmp))
3867 *expr_p = unshare_expr (DECL_VALUE_EXPR (tmp));
3876 /* Allow callbacks into the gimplifier during optimization. */
3881 /* If this is a comparison of objects of aggregate type, handle
3882 it specially (by converting to a call to memcmp). It would be
3883 nice to only have to do this for variable-sized objects, but
3884 then we'd have to allow the same nest of reference nodes we
3885 allow for MODIFY_EXPR and that's too complex. */
3886 if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3887 && (AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 1)))))
3888 ret = gimplify_variable_sized_compare (expr_p);
3890 /* If *EXPR_P does not need to be special-cased, handle it
3891 according to its class. */
3892 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '1')
3893 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3894 post_p, is_gimple_val, fb_rvalue);
3895 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '2'
3896 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3897 || TREE_CODE (*expr_p) == TRUTH_AND_EXPR
3898 || TREE_CODE (*expr_p) == TRUTH_OR_EXPR
3899 || TREE_CODE (*expr_p) == TRUTH_XOR_EXPR)
3901 enum gimplify_status r0, r1;
3903 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3904 post_p, is_gimple_val, fb_rvalue);
3905 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p,
3906 post_p, is_gimple_val, fb_rvalue);
3910 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'd'
3911 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'c')
3917 /* Fail if we don't know how to handle this tree code. */
3920 recalculate_side_effects (*expr_p);
3924 /* If we replaced *expr_p, gimplify again. */
3925 if (ret == GS_OK && (*expr_p == NULL || *expr_p == save_expr))
3928 while (ret == GS_OK);
3930 /* If we encountered an error_mark somewhere nested inside, either
3931 stub out the statement or propagate the error back out. */
3932 if (ret == GS_ERROR)
3939 #ifdef ENABLE_CHECKING
3940 /* This was only valid as a return value from the langhook, which
3941 we handled. Make sure it doesn't escape from any other context. */
3942 if (ret == GS_UNHANDLED)
3946 if (fallback == fb_none && *expr_p && !is_gimple_stmt (*expr_p))
3948 /* We aren't looking for a value, and we don't have a valid
3949 statement. If it doesn't have side-effects, throw it away. */
3950 if (!TREE_SIDE_EFFECTS (*expr_p))
3952 else if (!TREE_THIS_VOLATILE (*expr_p))
3954 /* This is probably a _REF that contains something nested that
3955 has side effects. Recurse through the operands to find it. */
3956 enum tree_code code = TREE_CODE (*expr_p);
3958 if (code == COMPONENT_REF
3959 || code == REALPART_EXPR || code == IMAGPART_EXPR)
3960 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3961 gimple_test_f, fallback);
3962 else if (code == ARRAY_REF || code == ARRAY_RANGE_REF)
3964 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3965 gimple_test_f, fallback);
3966 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3967 gimple_test_f, fallback);
3970 /* Anything else with side-effects
3971 must be converted to a valid statement before we get here. */
3976 else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p)))
3978 /* Historically, the compiler has treated a bare
3979 reference to a volatile lvalue as forcing a load. */
3980 tree tmp = create_tmp_var (TREE_TYPE (*expr_p), "vol");
3981 *expr_p = build (MODIFY_EXPR, TREE_TYPE (tmp), tmp, *expr_p);
3984 /* We can't do anything useful with a volatile reference to
3985 incomplete type, so just throw it away. */
3989 /* If we are gimplifying at the statement level, we're done. Tack
3990 everything together and replace the original statement with the
3992 if (fallback == fb_none || is_statement)
3994 if (internal_pre || internal_post)
3996 append_to_statement_list (*expr_p, &internal_pre);
3997 append_to_statement_list (internal_post, &internal_pre);
3998 annotate_all_with_locus (&internal_pre, input_location);
3999 *expr_p = internal_pre;
4003 else if (TREE_CODE (*expr_p) == STATEMENT_LIST)
4004 annotate_all_with_locus (expr_p, input_location);
4006 annotate_one_with_locus (*expr_p, input_location);
4010 /* Otherwise we're gimplifying a subexpression, so the resulting value is
4013 /* If it's sufficiently simple already, we're done. Unless we are
4014 handling some post-effects internally; if that's the case, we need to
4015 copy into a temp before adding the post-effects to the tree. */
4016 if (!internal_post && (*gimple_test_f) (*expr_p))
4019 /* Otherwise, we need to create a new temporary for the gimplified
4022 /* We can't return an lvalue if we have an internal postqueue. The
4023 object the lvalue refers to would (probably) be modified by the
4024 postqueue; we need to copy the value out first, which means an
4026 if ((fallback & fb_lvalue) && !internal_post
4027 && is_gimple_addressable (*expr_p))
4029 /* An lvalue will do. Take the address of the expression, store it
4030 in a temporary, and replace the expression with an INDIRECT_REF of
4032 tmp = build_fold_addr_expr (*expr_p);
4033 gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue);
4034 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp);
4036 else if ((fallback & fb_rvalue) && is_gimple_formal_tmp_rhs (*expr_p))
4038 #if defined ENABLE_CHECKING
4039 if (VOID_TYPE_P (TREE_TYPE (*expr_p)))
4043 /* An rvalue will do. Assign the gimplified expression into a new
4044 temporary TMP and replace the original expression with TMP. */
4046 if (internal_post || (fallback & fb_lvalue))
4047 /* The postqueue might change the value of the expression between
4048 the initialization and use of the temporary, so we can't use a
4049 formal temp. FIXME do we care? */
4050 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
4052 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
4053 DECL_GIMPLE_FORMAL_TEMP_P (*expr_p) = 1;
4055 else if (fallback & fb_mayfail)
4057 /* If this is an asm statement, and the user asked for the impossible,
4058 don't abort. Fail and let gimplify_asm_expr issue an error. */
4064 fprintf (stderr, "gimplification failed:\n");
4065 print_generic_expr (stderr, *expr_p, 0);
4066 debug_tree (*expr_p);
4070 #if defined ENABLE_CHECKING
4071 /* Make sure the temporary matches our predicate. */
4072 if (!(*gimple_test_f) (*expr_p))
4078 annotate_all_with_locus (&internal_post, input_location);
4079 append_to_statement_list (internal_post, pre_p);
4083 input_location = saved_location;
4087 /* Look through TYPE for variable-sized objects and gimplify each such
4088 size that we find. Add to LIST_P any statements generated. */
4091 gimplify_type_sizes (tree type, tree *list_p)
4095 switch (TREE_CODE (type))
4105 gimplify_one_sizepos (&TYPE_MIN_VALUE (type), list_p);
4106 gimplify_one_sizepos (&TYPE_MAX_VALUE (type), list_p);
4110 /* These anonymous types don't have declarations, so handle them here. */
4111 gimplify_type_sizes (TYPE_DOMAIN (type), list_p);
4116 case QUAL_UNION_TYPE:
4117 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4118 if (TREE_CODE (field) == FIELD_DECL)
4119 gimplify_one_sizepos (&DECL_FIELD_OFFSET (field), list_p);
4126 gimplify_one_sizepos (&TYPE_SIZE (type), list_p);
4127 gimplify_one_sizepos (&TYPE_SIZE_UNIT (type), list_p);
4130 /* Subroutine of the above to gimplify one size or position, *EXPR_P.
4131 We add any required statements to STMT_P. */
4134 gimplify_one_sizepos (tree *expr_p, tree *stmt_p)
4136 /* We don't do anything if the value isn't there, is constant, or contains
4137 A PLACEHOLDER_EXPR. We also don't want to do anything if it's already
4138 a VAR_DECL. If it's a VAR_DECL from another function, the gimplfier
4139 will want to replace it with a new variable, but that will cause problems
4140 if this type is from outside the function. It's OK to have that here. */
4141 if (*expr_p == NULL_TREE || TREE_CONSTANT (*expr_p)
4142 || TREE_CODE (*expr_p) == VAR_DECL
4143 || CONTAINS_PLACEHOLDER_P (*expr_p))
4146 gimplify_expr (expr_p, stmt_p, NULL, is_gimple_val, fb_rvalue);
4149 #ifdef ENABLE_CHECKING
4150 /* Compare types A and B for a "close enough" match. */
4153 cpt_same_type (tree a, tree b)
4155 if (lang_hooks.types_compatible_p (a, b))
4158 /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't
4159 link them together. This routine is intended to catch type errors
4160 that will affect the optimizers, and the optimizers don't add new
4161 dereferences of function pointers, so ignore it. */
4162 if ((TREE_CODE (a) == FUNCTION_TYPE || TREE_CODE (a) == METHOD_TYPE)
4163 && (TREE_CODE (b) == FUNCTION_TYPE || TREE_CODE (b) == METHOD_TYPE))
4166 /* ??? The C FE pushes type qualifiers after the fact into the type of
4167 the element from the type of the array. See build_unary_op's handling
4168 of ADDR_EXPR. This seems wrong -- if we were going to do this, we
4169 should have done it when creating the variable in the first place.
4170 Alternately, why aren't the two array types made variants? */
4171 if (TREE_CODE (a) == ARRAY_TYPE && TREE_CODE (b) == ARRAY_TYPE)
4172 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4174 /* And because of those, we have to recurse down through pointers. */
4175 if (POINTER_TYPE_P (a) && POINTER_TYPE_P (b))
4176 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4181 /* Check for some cases of the front end missing cast expressions.
4182 The type of a dereference should correspond to the pointer type;
4183 similarly the type of an address should match its object. */
4186 check_pointer_types_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
4187 void *data ATTRIBUTE_UNUSED)
4190 tree ptype, otype, dtype;
4192 switch (TREE_CODE (t))
4196 otype = TREE_TYPE (t);
4197 ptype = TREE_TYPE (TREE_OPERAND (t, 0));
4198 dtype = TREE_TYPE (ptype);
4199 if (!cpt_same_type (otype, dtype))
4204 ptype = TREE_TYPE (t);
4205 otype = TREE_TYPE (TREE_OPERAND (t, 0));
4206 dtype = TREE_TYPE (ptype);
4207 if (!cpt_same_type (otype, dtype))
4209 /* &array is allowed to produce a pointer to the element, rather than
4210 a pointer to the array type. We must allow this in order to
4211 properly represent assigning the address of an array in C into
4212 pointer to the element type. */
4213 if (TREE_CODE (otype) == ARRAY_TYPE
4214 && POINTER_TYPE_P (ptype)
4215 && cpt_same_type (TREE_TYPE (otype), dtype))
4230 /* Gimplify the body of statements pointed by BODY_P. FNDECL is the
4231 function decl containing BODY. */
4234 gimplify_body (tree *body_p, tree fndecl)
4236 location_t saved_location = input_location;
4239 timevar_push (TV_TREE_GIMPLIFY);
4240 push_gimplify_context ();
4242 /* Unshare most shared trees in the body and in that of any nested functions.
4243 It would seem we don't have to do this for nested functions because
4244 they are supposed to be output and then the outer function gimplified
4245 first, but the g++ front end doesn't always do it that way. */
4246 unshare_body (body_p, fndecl);
4247 unvisit_body (body_p, fndecl);
4249 /* Make sure input_location isn't set to something wierd. */
4250 input_location = DECL_SOURCE_LOCATION (fndecl);
4252 /* Gimplify the function's body. */
4253 gimplify_stmt (body_p);
4256 /* Unshare again, in case gimplification was sloppy. */
4257 unshare_all_trees (body);
4260 body = alloc_stmt_list ();
4261 else if (TREE_CODE (body) == STATEMENT_LIST)
4263 tree t = expr_only (*body_p);
4268 /* If there isn't an outer BIND_EXPR, add one. */
4269 if (TREE_CODE (body) != BIND_EXPR)
4271 tree b = build (BIND_EXPR, void_type_node, NULL_TREE,
4272 NULL_TREE, NULL_TREE);
4273 TREE_SIDE_EFFECTS (b) = 1;
4274 append_to_statement_list_force (body, &BIND_EXPR_BODY (b));
4279 pop_gimplify_context (body);
4281 #ifdef ENABLE_CHECKING
4282 walk_tree (body_p, check_pointer_types_r, NULL, NULL);
4285 timevar_pop (TV_TREE_GIMPLIFY);
4286 input_location = saved_location;
4289 /* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL
4290 node for the function we want to gimplify. */
4293 gimplify_function_tree (tree fndecl)
4297 oldfn = current_function_decl;
4298 current_function_decl = fndecl;
4300 gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl);
4302 /* If we're instrumenting function entry/exit, then prepend the call to
4303 the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
4304 catch the exit hook. */
4305 /* ??? Add some way to ignore exceptions for this TFE. */
4306 if (flag_instrument_function_entry_exit
4307 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl))
4311 tf = build (TRY_FINALLY_EXPR, void_type_node, NULL, NULL);
4312 TREE_SIDE_EFFECTS (tf) = 1;
4313 x = DECL_SAVED_TREE (fndecl);
4314 append_to_statement_list (x, &TREE_OPERAND (tf, 0));
4315 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_EXIT];
4316 x = build_function_call_expr (x, NULL);
4317 append_to_statement_list (x, &TREE_OPERAND (tf, 1));
4319 bind = build (BIND_EXPR, void_type_node, NULL, NULL, NULL);
4320 TREE_SIDE_EFFECTS (bind) = 1;
4321 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_ENTER];
4322 x = build_function_call_expr (x, NULL);
4323 append_to_statement_list (x, &BIND_EXPR_BODY (bind));
4324 append_to_statement_list (tf, &BIND_EXPR_BODY (bind));
4326 DECL_SAVED_TREE (fndecl) = bind;
4329 current_function_decl = oldfn;
4332 #include "gt-gimplify.h"