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 (dctype)
1397 *expr_p = build1 (ADDR_EXPR, ctype, *expr_p);
1400 /* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
1401 underneath as appropriate. */
1403 static enum gimplify_status
1404 gimplify_conversion (tree *expr_p)
1406 /* If we still have a conversion at the toplevel, then strip
1407 away all but the outermost conversion. */
1408 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1410 STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0));
1412 /* And remove the outermost conversion if it's useless. */
1413 if (tree_ssa_useless_type_conversion (*expr_p))
1414 *expr_p = TREE_OPERAND (*expr_p, 0);
1417 /* If we still have a conversion at the toplevel,
1418 then canonicalize some constructs. */
1419 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1421 tree sub = TREE_OPERAND (*expr_p, 0);
1423 /* If a NOP conversion is changing the type of a COMPONENT_REF
1424 expression, then canonicalize its type now in order to expose more
1425 redundant conversions. */
1426 if (TREE_CODE (sub) == COMPONENT_REF)
1427 canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0));
1429 /* If a NOP conversion is changing a pointer to array of foo
1430 to a pointer to foo, embed that change in the ADDR_EXPR. */
1431 else if (TREE_CODE (sub) == ADDR_EXPR)
1432 canonicalize_addr_expr (expr_p);
1438 /* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
1439 node pointed by EXPR_P.
1442 : min_lval '[' val ']'
1444 | compound_lval '[' val ']'
1445 | compound_lval '.' ID
1447 This is not part of the original SIMPLE definition, which separates
1448 array and member references, but it seems reasonable to handle them
1449 together. Also, this way we don't run into problems with union
1450 aliasing; gcc requires that for accesses through a union to alias, the
1451 union reference must be explicit, which was not always the case when we
1452 were splitting up array and member refs.
1454 PRE_P points to the list where side effects that must happen before
1455 *EXPR_P should be stored.
1457 POST_P points to the list where side effects that must happen after
1458 *EXPR_P should be stored. */
1460 static enum gimplify_status
1461 gimplify_compound_lval (tree *expr_p, tree *pre_p,
1462 tree *post_p, fallback_t fallback)
1466 enum gimplify_status ret = GS_OK, tret;
1469 /* Create a stack of the subexpressions so later we can walk them in
1470 order from inner to outer. */
1471 VARRAY_TREE_INIT (stack, 10, "stack");
1473 /* We can either handle REALPART_EXPR, IMAGEPART_EXPR anything that
1474 handled_components can deal with. */
1476 (handled_component_p (*p)
1477 || TREE_CODE (*p) == REALPART_EXPR || TREE_CODE (*p) == IMAGPART_EXPR);
1478 p = &TREE_OPERAND (*p, 0))
1479 VARRAY_PUSH_TREE (stack, *p);
1481 #if defined ENABLE_CHECKING
1482 if (VARRAY_ACTIVE_SIZE (stack) == 0)
1486 /* Now STACK is a stack of pointers to all the refs we've walked through
1487 and P points to the innermost expression.
1489 Java requires that we elaborated nodes in source order. That
1490 means we must gimplify the inner expression followed by each of
1491 the indices, in order. But we can't gimplify the inner
1492 expression until we deal with any variable bounds, sizes, or
1493 positions in order to deal with PLACEHOLDER_EXPRs.
1495 So we do this in three steps. First we deal with the annotations
1496 for any variables in the components, then we gimplify the base,
1497 then we gimplify any indices, from left to right. */
1498 for (i = VARRAY_ACTIVE_SIZE (stack) - 1; i >= 0; i--)
1500 tree t = VARRAY_TREE (stack, i);
1502 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1504 /* Gimplify the low bound and element type size and put them into
1505 the ARRAY_REF. If these values are set, they have already been
1507 if (!TREE_OPERAND (t, 2))
1509 tree low = unshare_expr (array_ref_low_bound (t));
1510 if (!is_gimple_min_invariant (low))
1512 TREE_OPERAND (t, 2) = low;
1513 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1514 is_gimple_formal_tmp_reg, fb_rvalue);
1515 ret = MIN (ret, tret);
1519 if (!TREE_OPERAND (t, 3))
1521 tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
1522 tree elmt_size = unshare_expr (array_ref_element_size (t));
1523 tree factor = size_int (TYPE_ALIGN (elmt_type) / BITS_PER_UNIT);
1525 /* Divide the element size by the alignment of the element
1527 elmt_size = size_binop (EXACT_DIV_EXPR, elmt_size, factor);
1529 if (!is_gimple_min_invariant (elmt_size))
1531 TREE_OPERAND (t, 3) = elmt_size;
1532 tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p,
1533 is_gimple_formal_tmp_reg, fb_rvalue);
1534 ret = MIN (ret, tret);
1538 else if (TREE_CODE (t) == COMPONENT_REF)
1540 /* Set the field offset into T and gimplify it. */
1541 if (!TREE_OPERAND (t, 2))
1543 tree offset = unshare_expr (component_ref_field_offset (t));
1544 tree field = TREE_OPERAND (t, 1);
1546 = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
1548 /* Divide the offset by its alignment. */
1549 offset = size_binop (EXACT_DIV_EXPR, offset, factor);
1551 if (!is_gimple_min_invariant (offset))
1553 TREE_OPERAND (t, 2) = offset;
1554 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1555 is_gimple_formal_tmp_reg, fb_rvalue);
1556 ret = MIN (ret, tret);
1562 /* Step 2 is to gimplify the base expression. */
1563 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1564 ret = MIN (ret, tret);
1566 /* And finally, the indices and operands to BIT_FIELD_REF. During this
1567 loop we also remove any useless conversions. */
1568 for (; VARRAY_ACTIVE_SIZE (stack) > 0; )
1570 tree t = VARRAY_TOP_TREE (stack);
1572 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1574 /* Gimplify the dimension.
1575 Temporary fix for gcc.c-torture/execute/20040313-1.c.
1576 Gimplify non-constant array indices into a temporary
1578 FIXME - The real fix is to gimplify post-modify
1579 expressions into a minimal gimple lvalue. However, that
1580 exposes bugs in alias analysis. The alias analyzer does
1581 not handle &PTR->FIELD very well. Will fix after the
1582 branch is merged into mainline (dnovillo 2004-05-03). */
1583 if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
1585 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1586 is_gimple_formal_tmp_reg, fb_rvalue);
1587 ret = MIN (ret, tret);
1590 else if (TREE_CODE (t) == BIT_FIELD_REF)
1592 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1593 is_gimple_val, fb_rvalue);
1594 ret = MIN (ret, tret);
1595 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1596 is_gimple_val, fb_rvalue);
1597 ret = MIN (ret, tret);
1600 STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0));
1602 /* The innermost expression P may have originally had TREE_SIDE_EFFECTS
1603 set which would have caused all the outer expressions in EXPR_P
1604 leading to P to also have had TREE_SIDE_EFFECTS set. */
1605 recalculate_side_effects (t);
1609 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1610 ret = MIN (ret, tret);
1612 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
1613 if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF)
1615 canonicalize_component_ref (expr_p);
1616 ret = MIN (ret, GS_OK);
1622 /* Gimplify the self modifying expression pointed by EXPR_P (++, --, +=, -=).
1624 PRE_P points to the list where side effects that must happen before
1625 *EXPR_P should be stored.
1627 POST_P points to the list where side effects that must happen after
1628 *EXPR_P should be stored.
1630 WANT_VALUE is nonzero iff we want to use the value of this expression
1631 in another expression. */
1633 static enum gimplify_status
1634 gimplify_self_mod_expr (tree *expr_p, tree *pre_p, tree *post_p,
1637 enum tree_code code;
1638 tree lhs, lvalue, rhs, t1;
1640 enum tree_code arith_code;
1641 enum gimplify_status ret;
1643 code = TREE_CODE (*expr_p);
1645 #if defined ENABLE_CHECKING
1646 if (code != POSTINCREMENT_EXPR
1647 && code != POSTDECREMENT_EXPR
1648 && code != PREINCREMENT_EXPR
1649 && code != PREDECREMENT_EXPR)
1653 /* Prefix or postfix? */
1654 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
1655 /* Faster to treat as prefix if result is not used. */
1656 postfix = want_value;
1660 /* Add or subtract? */
1661 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
1662 arith_code = PLUS_EXPR;
1664 arith_code = MINUS_EXPR;
1666 /* Gimplify the LHS into a GIMPLE lvalue. */
1667 lvalue = TREE_OPERAND (*expr_p, 0);
1668 ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
1669 if (ret == GS_ERROR)
1672 /* Extract the operands to the arithmetic operation. */
1674 rhs = TREE_OPERAND (*expr_p, 1);
1676 /* For postfix operator, we evaluate the LHS to an rvalue and then use
1677 that as the result value and in the postqueue operation. */
1680 ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
1681 if (ret == GS_ERROR)
1685 t1 = build (arith_code, TREE_TYPE (*expr_p), lhs, rhs);
1686 t1 = build (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
1690 gimplify_and_add (t1, post_p);
1701 /* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
1704 maybe_with_size_expr (tree *expr_p)
1706 tree expr = *expr_p;
1707 tree type = TREE_TYPE (expr);
1710 /* If we've already wrapped this or the type is error_mark_node, we can't do
1712 if (TREE_CODE (expr) == WITH_SIZE_EXPR
1713 || type == error_mark_node)
1716 /* If the size isn't known or is a constant, we have nothing to do. */
1717 size = TYPE_SIZE_UNIT (type);
1718 if (!size || TREE_CODE (size) == INTEGER_CST)
1721 /* Otherwise, make a WITH_SIZE_EXPR. */
1722 size = unshare_expr (size);
1723 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr);
1724 *expr_p = build2 (WITH_SIZE_EXPR, type, expr, size);
1727 /* Subroutine of gimplify_call_expr: Gimplify a single argument. */
1729 static enum gimplify_status
1730 gimplify_arg (tree *expr_p, tree *pre_p)
1732 bool (*test) (tree);
1735 /* In general, we allow lvalues for function arguments to avoid
1736 extra overhead of copying large aggregates out of even larger
1737 aggregates into temporaries only to copy the temporaries to
1738 the argument list. Make optimizers happy by pulling out to
1739 temporaries those types that fit in registers. */
1740 if (is_gimple_reg_type (TREE_TYPE (*expr_p)))
1741 test = is_gimple_val, fb = fb_rvalue;
1743 test = is_gimple_lvalue, fb = fb_either;
1745 /* If this is a variable sized type, we must remember the size. */
1746 maybe_with_size_expr (expr_p);
1748 /* There is a sequence point before a function call. Side effects in
1749 the argument list must occur before the actual call. So, when
1750 gimplifying arguments, force gimplify_expr to use an internal
1751 post queue which is then appended to the end of PRE_P. */
1752 return gimplify_expr (expr_p, pre_p, NULL, test, fb);
1755 /* Gimplify the CALL_EXPR node pointed by EXPR_P. PRE_P points to the
1756 list where side effects that must happen before *EXPR_P should be stored.
1757 WANT_VALUE is true if the result of the call is desired. */
1759 static enum gimplify_status
1760 gimplify_call_expr (tree *expr_p, tree *pre_p, bool want_value)
1764 enum gimplify_status ret;
1766 #if defined ENABLE_CHECKING
1767 if (TREE_CODE (*expr_p) != CALL_EXPR)
1771 /* For reliable diagnostics during inlining, it is necessary that
1772 every call_expr be annotated with file and line. */
1773 if (! EXPR_HAS_LOCATION (*expr_p))
1774 SET_EXPR_LOCATION (*expr_p, input_location);
1776 /* This may be a call to a builtin function.
1778 Builtin function calls may be transformed into different
1779 (and more efficient) builtin function calls under certain
1780 circumstances. Unfortunately, gimplification can muck things
1781 up enough that the builtin expanders are not aware that certain
1782 transformations are still valid.
1784 So we attempt transformation/gimplification of the call before
1785 we gimplify the CALL_EXPR. At this time we do not manage to
1786 transform all calls in the same manner as the expanders do, but
1787 we do transform most of them. */
1788 decl = get_callee_fndecl (*expr_p);
1789 if (decl && DECL_BUILT_IN (decl))
1791 tree new = simplify_builtin (*expr_p, !want_value);
1793 if (new && new != *expr_p)
1795 /* There was a transformation of this call which computes the
1796 same value, but in a more efficient way. Return and try
1802 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_VA_START)
1803 /* Avoid gimplifying the second argument to va_start, which needs
1804 to be the plain PARM_DECL. */
1805 return gimplify_arg (&TREE_VALUE (TREE_OPERAND (*expr_p, 1)), pre_p);
1808 /* There is a sequence point before the call, so any side effects in
1809 the calling expression must occur before the actual call. Force
1810 gimplify_expr to use an internal post queue. */
1811 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, NULL,
1812 is_gimple_call_addr, fb_rvalue);
1814 if (PUSH_ARGS_REVERSED)
1815 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1816 for (arglist = TREE_OPERAND (*expr_p, 1); arglist;
1817 arglist = TREE_CHAIN (arglist))
1819 enum gimplify_status t;
1821 t = gimplify_arg (&TREE_VALUE (arglist), pre_p);
1826 if (PUSH_ARGS_REVERSED)
1827 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1829 /* Try this again in case gimplification exposed something. */
1830 if (ret != GS_ERROR && decl && DECL_BUILT_IN (decl))
1832 tree new = simplify_builtin (*expr_p, !want_value);
1834 if (new && new != *expr_p)
1836 /* There was a transformation of this call which computes the
1837 same value, but in a more efficient way. Return and try
1844 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
1845 decl. This allows us to eliminate redundant or useless
1846 calls to "const" functions. */
1847 if (TREE_CODE (*expr_p) == CALL_EXPR
1848 && (call_expr_flags (*expr_p) & (ECF_CONST | ECF_PURE)))
1849 TREE_SIDE_EFFECTS (*expr_p) = 0;
1854 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
1855 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
1857 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
1858 condition is true or false, respectively. If null, we should generate
1859 our own to skip over the evaluation of this specific expression.
1861 This function is the tree equivalent of do_jump.
1863 shortcut_cond_r should only be called by shortcut_cond_expr. */
1866 shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p)
1868 tree local_label = NULL_TREE;
1869 tree t, expr = NULL;
1871 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
1872 retain the shortcut semantics. Just insert the gotos here;
1873 shortcut_cond_expr will append the real blocks later. */
1874 if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
1876 /* Turn if (a && b) into
1878 if (a); else goto no;
1879 if (b) goto yes; else goto no;
1882 if (false_label_p == NULL)
1883 false_label_p = &local_label;
1885 t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p);
1886 append_to_statement_list (t, &expr);
1888 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1890 append_to_statement_list (t, &expr);
1892 else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
1894 /* Turn if (a || b) into
1897 if (b) goto yes; else goto no;
1900 if (true_label_p == NULL)
1901 true_label_p = &local_label;
1903 t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL);
1904 append_to_statement_list (t, &expr);
1906 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1908 append_to_statement_list (t, &expr);
1910 else if (TREE_CODE (pred) == COND_EXPR)
1912 /* As long as we're messing with gotos, turn if (a ? b : c) into
1914 if (b) goto yes; else goto no;
1916 if (c) goto yes; else goto no; */
1917 expr = build (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
1918 shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1920 shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
1925 expr = build (COND_EXPR, void_type_node, pred,
1926 build_and_jump (true_label_p),
1927 build_and_jump (false_label_p));
1932 t = build1 (LABEL_EXPR, void_type_node, local_label);
1933 append_to_statement_list (t, &expr);
1940 shortcut_cond_expr (tree expr)
1942 tree pred = TREE_OPERAND (expr, 0);
1943 tree then_ = TREE_OPERAND (expr, 1);
1944 tree else_ = TREE_OPERAND (expr, 2);
1945 tree true_label, false_label, end_label, t;
1947 tree *false_label_p;
1948 bool emit_end, emit_false;
1949 bool then_se = then_ && TREE_SIDE_EFFECTS (then_);
1950 bool else_se = else_ && TREE_SIDE_EFFECTS (else_);
1952 /* First do simple transformations. */
1955 /* If there is no 'else', turn (a && b) into if (a) if (b). */
1956 while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
1958 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
1959 then_ = shortcut_cond_expr (expr);
1960 pred = TREE_OPERAND (pred, 0);
1961 expr = build (COND_EXPR, void_type_node, pred, then_, NULL_TREE);
1966 /* If there is no 'then', turn
1969 if (a); else if (b); else d. */
1970 while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
1972 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
1973 else_ = shortcut_cond_expr (expr);
1974 pred = TREE_OPERAND (pred, 0);
1975 expr = build (COND_EXPR, void_type_node, pred, NULL_TREE, else_);
1979 /* If we're done, great. */
1980 if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
1981 && TREE_CODE (pred) != TRUTH_ORIF_EXPR)
1984 /* Otherwise we need to mess with gotos. Change
1987 if (a); else goto no;
1990 and recursively gimplify the condition. */
1992 true_label = false_label = end_label = NULL_TREE;
1994 /* If our arms just jump somewhere, hijack those labels so we don't
1995 generate jumps to jumps. */
1998 && TREE_CODE (then_) == GOTO_EXPR
1999 && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
2001 true_label = GOTO_DESTINATION (then_);
2007 && TREE_CODE (else_) == GOTO_EXPR
2008 && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
2010 false_label = GOTO_DESTINATION (else_);
2015 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2017 true_label_p = &true_label;
2019 true_label_p = NULL;
2021 /* The 'else' branch also needs a label if it contains interesting code. */
2022 if (false_label || else_se)
2023 false_label_p = &false_label;
2025 false_label_p = NULL;
2027 /* If there was nothing else in our arms, just forward the label(s). */
2028 if (!then_se && !else_se)
2029 return shortcut_cond_r (pred, true_label_p, false_label_p);
2031 /* If our last subexpression already has a terminal label, reuse it. */
2033 expr = expr_last (else_);
2035 expr = expr_last (then_);
2038 if (expr && TREE_CODE (expr) == LABEL_EXPR)
2039 end_label = LABEL_EXPR_LABEL (expr);
2041 /* If we don't care about jumping to the 'else' branch, jump to the end
2042 if the condition is false. */
2044 false_label_p = &end_label;
2046 /* We only want to emit these labels if we aren't hijacking them. */
2047 emit_end = (end_label == NULL_TREE);
2048 emit_false = (false_label == NULL_TREE);
2050 pred = shortcut_cond_r (pred, true_label_p, false_label_p);
2053 append_to_statement_list (pred, &expr);
2055 append_to_statement_list (then_, &expr);
2058 t = build_and_jump (&end_label);
2059 append_to_statement_list (t, &expr);
2062 t = build1 (LABEL_EXPR, void_type_node, false_label);
2063 append_to_statement_list (t, &expr);
2065 append_to_statement_list (else_, &expr);
2067 if (emit_end && end_label)
2069 t = build1 (LABEL_EXPR, void_type_node, end_label);
2070 append_to_statement_list (t, &expr);
2076 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2079 gimple_boolify (tree expr)
2081 tree type = TREE_TYPE (expr);
2083 if (TREE_CODE (type) == BOOLEAN_TYPE)
2086 /* If this is the predicate of a COND_EXPR, it might not even be a
2088 expr = lang_hooks.truthvalue_conversion (expr);
2090 switch (TREE_CODE (expr))
2092 case TRUTH_AND_EXPR:
2094 case TRUTH_XOR_EXPR:
2095 case TRUTH_ANDIF_EXPR:
2096 case TRUTH_ORIF_EXPR:
2097 /* Also boolify the arguments of truth exprs. */
2098 TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
2101 case TRUTH_NOT_EXPR:
2102 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2105 case EQ_EXPR: case NE_EXPR:
2106 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2107 /* These expressions always produce boolean results. */
2108 TREE_TYPE (expr) = boolean_type_node;
2112 /* Other expressions that get here must have boolean values, but
2113 might need to be converted to the appropriate mode. */
2114 return convert (boolean_type_node, expr);
2118 /* Convert the conditional expression pointed by EXPR_P '(p) ? a : b;'
2127 The second form is used when *EXPR_P is of type void.
2129 TARGET is the tree for T1 above.
2131 PRE_P points to the list where side effects that must happen before
2132 *EXPR_P should be stored. */
2134 static enum gimplify_status
2135 gimplify_cond_expr (tree *expr_p, tree *pre_p, tree target)
2137 tree expr = *expr_p;
2138 tree tmp, tmp2, type;
2139 enum gimplify_status ret;
2141 type = TREE_TYPE (expr);
2143 TREE_TYPE (expr) = void_type_node;
2145 /* If this COND_EXPR has a value, copy the values into a temporary within
2147 else if (! VOID_TYPE_P (type))
2151 ret = gimplify_expr (&target, pre_p, NULL,
2152 is_gimple_min_lval, fb_lvalue);
2153 if (ret != GS_ERROR)
2156 tmp2 = unshare_expr (target);
2160 tmp2 = tmp = create_tmp_var (TREE_TYPE (expr), "iftmp");
2164 /* Build the then clause, 't1 = a;'. But don't build an assignment
2165 if this branch is void; in C++ it can be, if it's a throw. */
2166 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2167 TREE_OPERAND (expr, 1)
2168 = build (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 1));
2170 /* Build the else clause, 't1 = b;'. */
2171 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2172 TREE_OPERAND (expr, 2)
2173 = build (MODIFY_EXPR, void_type_node, tmp2, TREE_OPERAND (expr, 2));
2175 TREE_TYPE (expr) = void_type_node;
2176 recalculate_side_effects (expr);
2178 /* Move the COND_EXPR to the prequeue. */
2179 gimplify_and_add (expr, pre_p);
2185 /* Make sure the condition has BOOLEAN_TYPE. */
2186 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2188 /* Break apart && and || conditions. */
2189 if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
2190 || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
2192 expr = shortcut_cond_expr (expr);
2194 if (expr != *expr_p)
2198 /* We can't rely on gimplify_expr to re-gimplify the expanded
2199 form properly, as cleanups might cause the target labels to be
2200 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2201 set up a conditional context. */
2202 gimple_push_condition ();
2203 gimplify_stmt (expr_p);
2204 gimple_pop_condition (pre_p);
2210 /* Now do the normal gimplification. */
2211 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2212 is_gimple_condexpr, fb_rvalue);
2214 gimple_push_condition ();
2216 gimplify_to_stmt_list (&TREE_OPERAND (expr, 1));
2217 gimplify_to_stmt_list (&TREE_OPERAND (expr, 2));
2218 recalculate_side_effects (expr);
2220 gimple_pop_condition (pre_p);
2222 if (ret == GS_ERROR)
2224 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2226 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 2)))
2227 /* Rewrite "if (a); else b" to "if (!a) b" */
2229 TREE_OPERAND (expr, 0) = invert_truthvalue (TREE_OPERAND (expr, 0));
2230 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2231 is_gimple_condexpr, fb_rvalue);
2233 tmp = TREE_OPERAND (expr, 1);
2234 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 2);
2235 TREE_OPERAND (expr, 2) = tmp;
2238 /* Both arms are empty; replace the COND_EXPR with its predicate. */
2239 expr = TREE_OPERAND (expr, 0);
2245 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2246 a call to __builtin_memcpy. */
2248 static enum gimplify_status
2249 gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value)
2251 tree args, t, to, to_ptr, from;
2253 to = TREE_OPERAND (*expr_p, 0);
2254 from = TREE_OPERAND (*expr_p, 1);
2256 args = tree_cons (NULL, size, NULL);
2258 t = build_fold_addr_expr (from);
2259 args = tree_cons (NULL, t, args);
2261 to_ptr = build_fold_addr_expr (to);
2262 args = tree_cons (NULL, to_ptr, args);
2263 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
2264 t = build_function_call_expr (t, args);
2268 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2269 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2276 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2277 a call to __builtin_memset. In this case we know that the RHS is
2278 a CONSTRUCTOR with an empty element list. */
2280 static enum gimplify_status
2281 gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value)
2283 tree args, t, to, to_ptr;
2285 to = TREE_OPERAND (*expr_p, 0);
2287 args = tree_cons (NULL, size, NULL);
2289 args = tree_cons (NULL, integer_zero_node, args);
2291 to_ptr = build_fold_addr_expr (to);
2292 args = tree_cons (NULL, to_ptr, args);
2293 t = implicit_built_in_decls[BUILT_IN_MEMSET];
2294 t = build_function_call_expr (t, args);
2298 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2299 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2306 /* A subroutine of gimplify_init_ctor_preeval. Called via walk_tree,
2307 determine, cautiously, if a CONSTRUCTOR overlaps the lhs of an
2308 assignment. Returns non-null if we detect a potential overlap. */
2310 struct gimplify_init_ctor_preeval_data
2312 /* The base decl of the lhs object. May be NULL, in which case we
2313 have to assume the lhs is indirect. */
2316 /* The alias set of the lhs object. */
2321 gimplify_init_ctor_preeval_1 (tree *tp, int *walk_subtrees, void *xdata)
2323 struct gimplify_init_ctor_preeval_data *data
2324 = (struct gimplify_init_ctor_preeval_data *) xdata;
2327 /* If we find the base object, obviously we have overlap. */
2328 if (data->lhs_base_decl == t)
2331 /* If the constructor component is indirect, determine if we have a
2332 potential overlap with the lhs. The only bits of information we
2333 have to go on at this point are addressability and alias sets. */
2334 if (TREE_CODE (t) == INDIRECT_REF
2335 && (!data->lhs_base_decl || TREE_ADDRESSABLE (data->lhs_base_decl))
2336 && alias_sets_conflict_p (data->lhs_alias_set, get_alias_set (t)))
2339 if (DECL_P (t) || TYPE_P (t))
2344 /* A subroutine of gimplify_init_constructor. Pre-evaluate *EXPR_P,
2345 force values that overlap with the lhs (as described by *DATA)
2346 into temporaries. */
2349 gimplify_init_ctor_preeval (tree *expr_p, tree *pre_p, tree *post_p,
2350 struct gimplify_init_ctor_preeval_data *data)
2352 enum gimplify_status one;
2354 /* If the value is invariant, then there's nothing to pre-evaluate.
2355 But ensure it doesn't have any side-effects since a SAVE_EXPR is
2356 invariant but has side effects and might contain a reference to
2357 the object we're initializing. */
2358 if (TREE_INVARIANT (*expr_p) && !TREE_SIDE_EFFECTS (*expr_p))
2361 /* If the type has non-trivial constructors, we can't pre-evaluate. */
2362 if (TREE_ADDRESSABLE (TREE_TYPE (*expr_p)))
2365 /* Recurse for nested constructors. */
2366 if (TREE_CODE (*expr_p) == CONSTRUCTOR)
2369 for (list = CONSTRUCTOR_ELTS (*expr_p); list ; list = TREE_CHAIN (list))
2370 gimplify_init_ctor_preeval (&TREE_VALUE (list), pre_p, post_p, data);
2374 /* We can't preevaluate if the type contains a placeholder. */
2375 if (type_contains_placeholder_p (TREE_TYPE (*expr_p)))
2378 /* Gimplify the constructor element to something appropriate for the rhs
2379 of a MODIFY_EXPR. Given that we know the lhs is an aggregate, we know
2380 the gimplifier will consider this a store to memory. Doing this
2381 gimplification now means that we won't have to deal with complicated
2382 language-specific trees, nor trees like SAVE_EXPR that can induce
2383 exponential search behaviour. */
2384 one = gimplify_expr (expr_p, pre_p, post_p, is_gimple_mem_rhs, fb_rvalue);
2385 if (one == GS_ERROR)
2391 /* If we gimplified to a bare decl, we can be sure that it doesn't overlap
2392 with the lhs, since "a = { .x=a }" doesn't make sense. This will
2393 always be true for all scalars, since is_gimple_mem_rhs insists on a
2394 temporary variable for them. */
2395 if (DECL_P (*expr_p))
2398 /* If this is of variable size, we have no choice but to assume it doesn't
2399 overlap since we can't make a temporary for it. */
2400 if (!TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (*expr_p))))
2403 /* Otherwise, we must search for overlap ... */
2404 if (!walk_tree (expr_p, gimplify_init_ctor_preeval_1, data, NULL))
2407 /* ... and if found, force the value into a temporary. */
2408 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
2411 /* A subroutine of gimplify_init_constructor. Generate individual
2412 MODIFY_EXPRs for a CONSTRUCTOR. OBJECT is the LHS against which the
2413 assignments should happen. LIST is the CONSTRUCTOR_ELTS of the
2414 CONSTRUCTOR. CLEARED is true if the entire LHS object has been
2418 gimplify_init_ctor_eval (tree object, tree list, tree *pre_p, bool cleared)
2420 tree array_elt_type = NULL;
2422 if (TREE_CODE (TREE_TYPE (object)) == ARRAY_TYPE)
2423 array_elt_type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object)));
2425 for (; list; list = TREE_CHAIN (list))
2427 tree purpose, value, cref, init;
2429 purpose = TREE_PURPOSE (list);
2430 value = TREE_VALUE (list);
2432 /* NULL values are created above for gimplification errors. */
2436 if (cleared && initializer_zerop (value))
2441 /* ??? Here's to hoping the front end fills in all of the indicies,
2442 so we don't have to figure out what's missing ourselves. */
2445 /* ??? Need to handle this. */
2446 if (TREE_CODE (purpose) == RANGE_EXPR)
2449 cref = build (ARRAY_REF, array_elt_type, unshare_expr (object),
2450 purpose, NULL_TREE, NULL_TREE);
2453 cref = build (COMPONENT_REF, TREE_TYPE (purpose),
2454 unshare_expr (object), purpose, NULL_TREE);
2456 if (TREE_CODE (value) == CONSTRUCTOR)
2457 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
2461 init = build (MODIFY_EXPR, TREE_TYPE (cref), cref, value);
2462 gimplify_and_add (init, pre_p);
2467 /* A subroutine of gimplify_modify_expr. Break out elements of a
2468 CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.
2470 Note that we still need to clear any elements that don't have explicit
2471 initializers, so if not all elements are initialized we keep the
2472 original MODIFY_EXPR, we just remove all of the constructor elements. */
2474 static enum gimplify_status
2475 gimplify_init_constructor (tree *expr_p, tree *pre_p,
2476 tree *post_p, bool want_value)
2479 tree ctor = TREE_OPERAND (*expr_p, 1);
2480 tree type = TREE_TYPE (ctor);
2481 enum gimplify_status ret;
2484 if (TREE_CODE (ctor) != CONSTRUCTOR)
2485 return GS_UNHANDLED;
2487 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
2488 is_gimple_lvalue, fb_lvalue);
2489 if (ret == GS_ERROR)
2491 object = TREE_OPERAND (*expr_p, 0);
2493 elt_list = CONSTRUCTOR_ELTS (ctor);
2496 switch (TREE_CODE (type))
2500 case QUAL_UNION_TYPE:
2503 struct gimplify_init_ctor_preeval_data preeval_data;
2504 HOST_WIDE_INT num_elements, num_nonzero_elements;
2505 HOST_WIDE_INT num_nonconstant_elements;
2508 /* Aggregate types must lower constructors to initialization of
2509 individual elements. The exception is that a CONSTRUCTOR node
2510 with no elements indicates zero-initialization of the whole. */
2511 if (elt_list == NULL)
2514 categorize_ctor_elements (ctor, &num_nonzero_elements,
2515 &num_nonconstant_elements);
2517 /* If a const aggregate variable is being initialized, then it
2518 should never be a lose to promote the variable to be static. */
2519 if (num_nonconstant_elements == 0
2520 && TREE_READONLY (object)
2521 && TREE_CODE (object) == VAR_DECL)
2523 DECL_INITIAL (object) = ctor;
2524 TREE_STATIC (object) = 1;
2525 if (!DECL_NAME (object))
2526 DECL_NAME (object) = create_tmp_var_name ("C");
2527 walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL);
2529 /* ??? C++ doesn't automatically append a .<number> to the
2530 assembler name, and even when it does, it looks a FE private
2531 data structures to figure out what that number should be,
2532 which are not set for this variable. I suppose this is
2533 important for local statics for inline functions, which aren't
2534 "local" in the object file sense. So in order to get a unique
2535 TU-local symbol, we must invoke the lhd version now. */
2536 lhd_set_decl_assembler_name (object);
2538 *expr_p = NULL_TREE;
2542 /* If there are "lots" of initialized elements, and all of them
2543 are valid address constants, then the entire initializer can
2544 be dropped to memory, and then memcpy'd out. */
2545 if (num_nonconstant_elements == 0)
2547 HOST_WIDE_INT size = int_size_in_bytes (type);
2550 /* ??? We can still get unbounded array types, at least
2551 from the C++ front end. This seems wrong, but attempt
2552 to work around it for now. */
2555 size = int_size_in_bytes (TREE_TYPE (object));
2557 TREE_TYPE (ctor) = type = TREE_TYPE (object);
2560 /* Find the maximum alignment we can assume for the object. */
2561 /* ??? Make use of DECL_OFFSET_ALIGN. */
2562 if (DECL_P (object))
2563 align = DECL_ALIGN (object);
2565 align = TYPE_ALIGN (type);
2567 if (size > 0 && !can_move_by_pieces (size, align))
2569 tree new = create_tmp_var_raw (type, "C");
2571 gimple_add_tmp_var (new);
2572 TREE_STATIC (new) = 1;
2573 TREE_READONLY (new) = 1;
2574 DECL_INITIAL (new) = ctor;
2575 if (align > DECL_ALIGN (new))
2577 DECL_ALIGN (new) = align;
2578 DECL_USER_ALIGN (new) = 1;
2580 walk_tree (&DECL_INITIAL (new), force_labels_r, NULL, NULL);
2582 TREE_OPERAND (*expr_p, 1) = new;
2584 /* This is no longer an assignment of a CONSTRUCTOR, but
2585 we still may have processing to do on the LHS. So
2586 pretend we didn't do anything here to let that happen. */
2587 return GS_UNHANDLED;
2591 /* If there are "lots" of initialized elements, even discounting
2592 those that are not address constants (and thus *must* be
2593 computed at runtime), then partition the constructor into
2594 constant and non-constant parts. Block copy the constant
2595 parts in, then generate code for the non-constant parts. */
2596 /* TODO. There's code in cp/typeck.c to do this. */
2598 num_elements = count_type_elements (TREE_TYPE (ctor));
2600 /* If there are "lots" of zeros, then block clear the object first. */
2602 if (num_elements - num_nonzero_elements > CLEAR_RATIO
2603 && num_nonzero_elements < num_elements/4)
2606 /* ??? This bit ought not be needed. For any element not present
2607 in the initializer, we should simply set them to zero. Except
2608 we'd need to *find* the elements that are not present, and that
2609 requires trickery to avoid quadratic compile-time behavior in
2610 large cases or excessive memory use in small cases. */
2613 HOST_WIDE_INT len = list_length (elt_list);
2614 if (TREE_CODE (type) == ARRAY_TYPE)
2616 tree nelts = array_type_nelts (type);
2617 if (!host_integerp (nelts, 1)
2618 || tree_low_cst (nelts, 1) + 1 != len)
2621 else if (len != fields_length (type))
2627 /* Zap the CONSTRUCTOR element list, which simplifies this case.
2628 Note that we still have to gimplify, in order to handle the
2629 case of variable sized types. Avoid shared tree structures. */
2630 CONSTRUCTOR_ELTS (ctor) = NULL_TREE;
2631 object = unshare_expr (object);
2632 gimplify_stmt (expr_p);
2633 append_to_statement_list (*expr_p, pre_p);
2636 preeval_data.lhs_base_decl = get_base_address (object);
2637 if (!DECL_P (preeval_data.lhs_base_decl))
2638 preeval_data.lhs_base_decl = NULL;
2639 preeval_data.lhs_alias_set = get_alias_set (object);
2641 gimplify_init_ctor_preeval (&TREE_OPERAND (*expr_p, 1),
2642 pre_p, post_p, &preeval_data);
2643 gimplify_init_ctor_eval (object, elt_list, pre_p, cleared);
2645 *expr_p = NULL_TREE;
2653 /* Extract the real and imaginary parts out of the ctor. */
2657 r = TREE_VALUE (elt_list);
2658 elt_list = TREE_CHAIN (elt_list);
2661 i = TREE_VALUE (elt_list);
2662 if (TREE_CHAIN (elt_list))
2666 if (r == NULL || i == NULL)
2668 tree zero = convert (TREE_TYPE (type), integer_zero_node);
2675 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
2676 represent creation of a complex value. */
2677 if (TREE_CONSTANT (r) && TREE_CONSTANT (i))
2679 ctor = build_complex (type, r, i);
2680 TREE_OPERAND (*expr_p, 1) = ctor;
2684 ctor = build (COMPLEX_EXPR, type, r, i);
2685 TREE_OPERAND (*expr_p, 1) = ctor;
2686 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
2687 rhs_predicate_for (TREE_OPERAND (*expr_p, 0)),
2694 /* Go ahead and simplify constant constructors to VECTOR_CST. */
2695 if (TREE_CONSTANT (ctor))
2696 TREE_OPERAND (*expr_p, 1) = build_vector (type, elt_list);
2699 /* Vector types use CONSTRUCTOR all the way through gimple
2700 compilation as a general initializer. */
2701 for (; elt_list; elt_list = TREE_CHAIN (elt_list))
2703 enum gimplify_status tret;
2704 tret = gimplify_expr (&TREE_VALUE (elt_list), pre_p, post_p,
2705 is_gimple_val, fb_rvalue);
2706 if (tret == GS_ERROR)
2713 /* So how did we get a CONSTRUCTOR for a scalar type? */
2717 if (ret == GS_ERROR)
2719 else if (want_value)
2721 append_to_statement_list (*expr_p, pre_p);
2729 /* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs
2730 based on the code of the RHS. We loop for as long as something changes. */
2732 static enum gimplify_status
2733 gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p,
2734 tree *post_p, bool want_value)
2736 enum gimplify_status ret = GS_OK;
2738 while (ret != GS_UNHANDLED)
2739 switch (TREE_CODE (*from_p))
2743 /* If we are initializing something from a TARGET_EXPR, strip the
2744 TARGET_EXPR and initialize it directly, if possible. This can't
2745 be done if the initializer is void, since that implies that the
2746 temporary is set in some non-trivial way.
2748 ??? What about code that pulls out the temp and uses it
2749 elsewhere? I think that such code never uses the TARGET_EXPR as
2750 an initializer. If I'm wrong, we'll abort because the temp won't
2751 have any RTL. In that case, I guess we'll need to replace
2752 references somehow. */
2753 tree init = TARGET_EXPR_INITIAL (*from_p);
2755 if (!VOID_TYPE_P (TREE_TYPE (init)))
2766 /* Remove any COMPOUND_EXPR in the RHS so the following cases will be
2768 gimplify_compound_expr (from_p, pre_p, true);
2773 /* If we're initializing from a CONSTRUCTOR, break this into
2774 individual MODIFY_EXPRs. */
2775 return gimplify_init_constructor (expr_p, pre_p, post_p, want_value);
2778 /* If we're assigning to a non-register type, push the assignment
2779 down into the branches. This is mandatory for ADDRESSABLE types,
2780 since we cannot generate temporaries for such, but it saves a
2781 copy in other cases as well. */
2782 if (!is_gimple_reg_type (TREE_TYPE (*from_p)))
2785 return gimplify_cond_expr (expr_p, pre_p, *to_p);
2799 /* Gimplify the MODIFY_EXPR node pointed by EXPR_P.
2805 PRE_P points to the list where side effects that must happen before
2806 *EXPR_P should be stored.
2808 POST_P points to the list where side effects that must happen after
2809 *EXPR_P should be stored.
2811 WANT_VALUE is nonzero iff we want to use the value of this expression
2812 in another expression. */
2814 static enum gimplify_status
2815 gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value)
2817 tree *from_p = &TREE_OPERAND (*expr_p, 1);
2818 tree *to_p = &TREE_OPERAND (*expr_p, 0);
2819 enum gimplify_status ret = GS_UNHANDLED;
2821 #if defined ENABLE_CHECKING
2822 if (TREE_CODE (*expr_p) != MODIFY_EXPR && TREE_CODE (*expr_p) != INIT_EXPR)
2826 /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer useful. */
2827 if (TREE_CODE (*expr_p) == INIT_EXPR)
2828 TREE_SET_CODE (*expr_p, MODIFY_EXPR);
2830 /* See if any simplifications can be done based on what the RHS is. */
2831 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2833 if (ret != GS_UNHANDLED)
2836 /* If the value being copied is of variable width, compute the length
2837 of the copy into a WITH_SIZE_EXPR. Note that we need to do this
2838 before gimplifying any of the operands so that we can resolve any
2839 PLACEHOLDER_EXPRs in the size. Also note that the RTL expander uses
2840 the size of the expression to be copied, not of the destination, so
2841 that is what we must here. */
2842 maybe_with_size_expr (from_p);
2844 ret = gimplify_expr (to_p, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
2845 if (ret == GS_ERROR)
2848 ret = gimplify_expr (from_p, pre_p, post_p,
2849 rhs_predicate_for (*to_p), fb_rvalue);
2850 if (ret == GS_ERROR)
2853 /* Now see if the above changed *from_p to something we handle specially. */
2854 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2856 if (ret != GS_UNHANDLED)
2859 /* If we've got a variable sized assignment between two lvalues (i.e. does
2860 not involve a call), then we can make things a bit more straightforward
2861 by converting the assignment to memcpy or memset. */
2862 if (TREE_CODE (*from_p) == WITH_SIZE_EXPR)
2864 tree from = TREE_OPERAND (*from_p, 0);
2865 tree size = TREE_OPERAND (*from_p, 1);
2867 if (TREE_CODE (from) == CONSTRUCTOR)
2868 return gimplify_modify_expr_to_memset (expr_p, size, want_value);
2869 if (is_gimple_addressable (from))
2872 return gimplify_modify_expr_to_memcpy (expr_p, size, want_value);
2878 append_to_statement_list (*expr_p, pre_p);
2886 /* Gimplify a comparison between two variable-sized objects. Do this
2887 with a call to BUILT_IN_MEMCMP. */
2889 static enum gimplify_status
2890 gimplify_variable_sized_compare (tree *expr_p)
2892 tree op0 = TREE_OPERAND (*expr_p, 0);
2893 tree op1 = TREE_OPERAND (*expr_p, 1);
2896 t = TYPE_SIZE_UNIT (TREE_TYPE (op0));
2897 t = unshare_expr (t);
2898 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, op0);
2899 args = tree_cons (NULL, t, NULL);
2900 t = build_fold_addr_expr (op1);
2901 args = tree_cons (NULL, t, args);
2902 dest = build_fold_addr_expr (op0);
2903 args = tree_cons (NULL, dest, args);
2904 t = implicit_built_in_decls[BUILT_IN_MEMCMP];
2905 t = build_function_call_expr (t, args);
2907 = build (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), t, integer_zero_node);
2912 /* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P
2913 points to the expression to gimplify.
2915 Expressions of the form 'a && b' are gimplified to:
2917 a && b ? true : false
2919 gimplify_cond_expr will do the rest.
2921 PRE_P points to the list where side effects that must happen before
2922 *EXPR_P should be stored. */
2924 static enum gimplify_status
2925 gimplify_boolean_expr (tree *expr_p)
2927 /* Preserve the original type of the expression. */
2928 tree type = TREE_TYPE (*expr_p);
2930 *expr_p = build (COND_EXPR, type, *expr_p,
2931 convert (type, boolean_true_node),
2932 convert (type, boolean_false_node));
2937 /* Gimplifies an expression sequence. This function gimplifies each
2938 expression and re-writes the original expression with the last
2939 expression of the sequence in GIMPLE form.
2941 PRE_P points to the list where the side effects for all the
2942 expressions in the sequence will be emitted.
2944 WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */
2945 /* ??? Should rearrange to share the pre-queue with all the indirect
2946 invocations of gimplify_expr. Would probably save on creations
2947 of statement_list nodes. */
2949 static enum gimplify_status
2950 gimplify_compound_expr (tree *expr_p, tree *pre_p, bool want_value)
2956 tree *sub_p = &TREE_OPERAND (t, 0);
2958 if (TREE_CODE (*sub_p) == COMPOUND_EXPR)
2959 gimplify_compound_expr (sub_p, pre_p, false);
2961 gimplify_stmt (sub_p);
2962 append_to_statement_list (*sub_p, pre_p);
2964 t = TREE_OPERAND (t, 1);
2966 while (TREE_CODE (t) == COMPOUND_EXPR);
2973 gimplify_stmt (expr_p);
2978 /* Gimplifies a statement list. These may be created either by an
2979 enlightened front-end, or by shortcut_cond_expr. */
2981 static enum gimplify_status
2982 gimplify_statement_list (tree *expr_p)
2984 tree_stmt_iterator i = tsi_start (*expr_p);
2986 while (!tsi_end_p (i))
2990 gimplify_stmt (tsi_stmt_ptr (i));
2995 else if (TREE_CODE (t) == STATEMENT_LIST)
2997 tsi_link_before (&i, t, TSI_SAME_STMT);
3007 /* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to
3008 gimplify. After gimplification, EXPR_P will point to a new temporary
3009 that holds the original value of the SAVE_EXPR node.
3011 PRE_P points to the list where side effects that must happen before
3012 *EXPR_P should be stored. */
3014 static enum gimplify_status
3015 gimplify_save_expr (tree *expr_p, tree *pre_p, tree *post_p)
3017 enum gimplify_status ret = GS_ALL_DONE;
3020 #if defined ENABLE_CHECKING
3021 if (TREE_CODE (*expr_p) != SAVE_EXPR)
3025 val = TREE_OPERAND (*expr_p, 0);
3027 /* If the SAVE_EXPR has not been resolved, then evaluate it once. */
3028 if (!SAVE_EXPR_RESOLVED_P (*expr_p))
3030 /* The operand may be a void-valued expression such as SAVE_EXPRs
3031 generated by the Java frontend for class initialization. It is
3032 being executed only for its side-effects. */
3033 if (TREE_TYPE (val) == void_type_node)
3035 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3036 is_gimple_stmt, fb_none);
3037 append_to_statement_list (TREE_OPERAND (*expr_p, 0), pre_p);
3041 val = get_initialized_tmp_var (val, pre_p, post_p);
3043 TREE_OPERAND (*expr_p, 0) = val;
3044 SAVE_EXPR_RESOLVED_P (*expr_p) = 1;
3052 /* Re-write the ADDR_EXPR node pointed by EXPR_P
3059 PRE_P points to the list where side effects that must happen before
3060 *EXPR_P should be stored.
3062 POST_P points to the list where side effects that must happen after
3063 *EXPR_P should be stored. */
3065 static enum gimplify_status
3066 gimplify_addr_expr (tree *expr_p, tree *pre_p, tree *post_p)
3068 tree expr = *expr_p;
3069 tree op0 = TREE_OPERAND (expr, 0);
3070 enum gimplify_status ret;
3072 switch (TREE_CODE (op0))
3075 /* Check if we are dealing with an expression of the form '&*ptr'.
3076 While the front end folds away '&*ptr' into 'ptr', these
3077 expressions may be generated internally by the compiler (e.g.,
3078 builtins like __builtin_va_end). */
3079 *expr_p = TREE_OPERAND (op0, 0);
3083 case VIEW_CONVERT_EXPR:
3084 /* Take the address of our operand and then convert it to the type of
3087 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3088 all clear. The impact of this transformation is even less clear. */
3089 *expr_p = fold_convert (TREE_TYPE (expr),
3090 build_fold_addr_expr (TREE_OPERAND (op0, 0)));
3095 /* We use fb_either here because the C frontend sometimes takes
3096 the address of a call that returns a struct; see
3097 gcc.dg/c99-array-lval-1.c. The gimplifier will correctly make
3098 the implied temporary explicit. */
3099 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, post_p,
3100 is_gimple_addressable, fb_either);
3101 if (ret != GS_ERROR)
3103 /* The above may have made an INDIRECT_REF (e.g, Ada's NULL_EXPR),
3104 so check for it here. It's not worth checking for the other
3106 if (TREE_CODE (TREE_OPERAND (expr, 0)) == INDIRECT_REF)
3108 *expr_p = TREE_OPERAND (TREE_OPERAND (expr, 0), 0);
3112 /* Make sure TREE_INVARIANT, TREE_CONSTANT, and TREE_SIDE_EFFECTS
3114 recompute_tree_invarant_for_addr_expr (expr);
3116 /* Mark the RHS addressable. */
3117 lang_hooks.mark_addressable (TREE_OPERAND (expr, 0));
3125 /* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple
3126 value; output operands should be a gimple lvalue. */
3128 static enum gimplify_status
3129 gimplify_asm_expr (tree *expr_p, tree *pre_p, tree *post_p)
3131 tree expr = *expr_p;
3132 int noutputs = list_length (ASM_OUTPUTS (expr));
3133 const char **oconstraints
3134 = (const char **) alloca ((noutputs) * sizeof (const char *));
3137 const char *constraint;
3138 bool allows_mem, allows_reg, is_inout;
3139 enum gimplify_status ret, tret;
3142 = resolve_asm_operand_names (ASM_STRING (expr), ASM_OUTPUTS (expr),
3146 for (i = 0, link = ASM_OUTPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3148 oconstraints[i] = constraint
3149 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3151 parse_output_constraint (&constraint, i, 0, 0,
3152 &allows_mem, &allows_reg, &is_inout);
3154 if (!allows_reg && allows_mem)
3155 lang_hooks.mark_addressable (TREE_VALUE (link));
3157 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3158 is_inout ? is_gimple_min_lval : is_gimple_lvalue,
3159 fb_lvalue | fb_mayfail);
3160 if (tret == GS_ERROR)
3162 error ("invalid lvalue in asm output %d", i);
3168 /* An input/output operand. To give the optimizers more
3169 flexibility, split it into separate input and output
3173 size_t constraint_len = strlen (constraint);
3175 /* Turn the in/out constraint into an output constraint. */
3176 char *p = xstrdup (constraint);
3178 TREE_VALUE (TREE_PURPOSE (link)) = build_string (constraint_len, p);
3181 /* And add a matching input constraint. */
3184 sprintf (buf, "%d", i);
3185 input = build_string (strlen (buf), buf);
3188 input = build_string (constraint_len - 1, constraint + 1);
3189 input = build_tree_list (build_tree_list (NULL_TREE, input),
3190 unshare_expr (TREE_VALUE (link)));
3191 ASM_INPUTS (expr) = chainon (ASM_INPUTS (expr), input);
3195 for (link = ASM_INPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3198 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3199 parse_input_constraint (&constraint, 0, 0, noutputs, 0,
3200 oconstraints, &allows_mem, &allows_reg);
3202 /* If the operand is a memory input, it should be an lvalue. */
3203 if (!allows_reg && allows_mem)
3205 lang_hooks.mark_addressable (TREE_VALUE (link));
3206 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3207 is_gimple_lvalue, fb_lvalue | fb_mayfail);
3208 if (tret == GS_ERROR)
3210 error ("memory input %d is not directly addressable", i);
3216 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3217 is_gimple_val, fb_rvalue);
3218 if (tret == GS_ERROR)
3226 /* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding
3227 WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
3228 gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
3229 return to this function.
3231 FIXME should we complexify the prequeue handling instead? Or use flags
3232 for all the cleanups and let the optimizer tighten them up? The current
3233 code seems pretty fragile; it will break on a cleanup within any
3234 non-conditional nesting. But any such nesting would be broken, anyway;
3235 we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
3236 and continues out of it. We can do that at the RTL level, though, so
3237 having an optimizer to tighten up try/finally regions would be a Good
3240 static enum gimplify_status
3241 gimplify_cleanup_point_expr (tree *expr_p, tree *pre_p)
3243 tree_stmt_iterator iter;
3246 tree temp = voidify_wrapper_expr (*expr_p, NULL);
3248 /* We only care about the number of conditions between the innermost
3249 CLEANUP_POINT_EXPR and the cleanup. So save and reset the count. */
3250 int old_conds = gimplify_ctxp->conditions;
3251 gimplify_ctxp->conditions = 0;
3253 body = TREE_OPERAND (*expr_p, 0);
3254 gimplify_to_stmt_list (&body);
3256 gimplify_ctxp->conditions = old_conds;
3258 for (iter = tsi_start (body); !tsi_end_p (iter); )
3260 tree *wce_p = tsi_stmt_ptr (iter);
3263 if (TREE_CODE (wce) == WITH_CLEANUP_EXPR)
3265 if (tsi_one_before_end_p (iter))
3267 tsi_link_before (&iter, TREE_OPERAND (wce, 0), TSI_SAME_STMT);
3274 enum tree_code code;
3276 if (CLEANUP_EH_ONLY (wce))
3277 code = TRY_CATCH_EXPR;
3279 code = TRY_FINALLY_EXPR;
3281 sl = tsi_split_statement_list_after (&iter);
3282 tfe = build (code, void_type_node, sl, NULL_TREE);
3283 append_to_statement_list (TREE_OPERAND (wce, 0),
3284 &TREE_OPERAND (tfe, 1));
3286 iter = tsi_start (sl);
3296 append_to_statement_list (body, pre_p);
3306 /* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP
3307 is the cleanup action required. */
3310 gimple_push_cleanup (tree var, tree cleanup, bool eh_only, tree *pre_p)
3314 /* Errors can result in improperly nested cleanups. Which results in
3315 confusion when trying to resolve the WITH_CLEANUP_EXPR. */
3316 if (errorcount || sorrycount)
3319 if (gimple_conditional_context ())
3321 /* If we're in a conditional context, this is more complex. We only
3322 want to run the cleanup if we actually ran the initialization that
3323 necessitates it, but we want to run it after the end of the
3324 conditional context. So we wrap the try/finally around the
3325 condition and use a flag to determine whether or not to actually
3326 run the destructor. Thus
3330 becomes (approximately)
3334 if (test) { A::A(temp); flag = 1; val = f(temp); }
3337 if (flag) A::~A(temp);
3342 tree flag = create_tmp_var (boolean_type_node, "cleanup");
3343 tree ffalse = build (MODIFY_EXPR, void_type_node, flag,
3344 boolean_false_node);
3345 tree ftrue = build (MODIFY_EXPR, void_type_node, flag,
3347 cleanup = build (COND_EXPR, void_type_node, flag, cleanup, NULL);
3348 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3349 append_to_statement_list (ffalse, &gimplify_ctxp->conditional_cleanups);
3350 append_to_statement_list (wce, &gimplify_ctxp->conditional_cleanups);
3351 append_to_statement_list (ftrue, pre_p);
3353 /* Because of this manipulation, and the EH edges that jump
3354 threading cannot redirect, the temporary (VAR) will appear
3355 to be used uninitialized. Don't warn. */
3356 TREE_NO_WARNING (var) = 1;
3360 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3361 CLEANUP_EH_ONLY (wce) = eh_only;
3362 append_to_statement_list (wce, pre_p);
3365 gimplify_stmt (&TREE_OPERAND (wce, 0));
3368 /* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */
3370 static enum gimplify_status
3371 gimplify_target_expr (tree *expr_p, tree *pre_p, tree *post_p)
3373 tree targ = *expr_p;
3374 tree temp = TARGET_EXPR_SLOT (targ);
3375 tree init = TARGET_EXPR_INITIAL (targ);
3376 enum gimplify_status ret;
3380 /* TARGET_EXPR temps aren't part of the enclosing block, so add it
3381 to the temps list. */
3382 gimple_add_tmp_var (temp);
3384 /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
3385 expression is supposed to initialize the slot. */
3386 if (VOID_TYPE_P (TREE_TYPE (init)))
3387 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, fb_none);
3390 /* Special handling for BIND_EXPR can result in fewer temps. */
3392 if (TREE_CODE (init) == BIND_EXPR)
3393 gimplify_bind_expr (&init, temp, pre_p);
3396 init = build (MODIFY_EXPR, void_type_node, temp, init);
3397 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt,
3401 if (ret == GS_ERROR)
3403 append_to_statement_list (init, pre_p);
3405 /* If needed, push the cleanup for the temp. */
3406 if (TARGET_EXPR_CLEANUP (targ))
3408 gimplify_stmt (&TARGET_EXPR_CLEANUP (targ));
3409 gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ),
3410 CLEANUP_EH_ONLY (targ), pre_p);
3413 /* Only expand this once. */
3414 TREE_OPERAND (targ, 3) = init;
3415 TARGET_EXPR_INITIAL (targ) = NULL_TREE;
3417 else if (!DECL_SEEN_IN_BIND_EXPR_P (temp))
3418 /* We should have expanded this before. */
3425 /* Gimplification of expression trees. */
3427 /* Gimplify an expression which appears at statement context; usually, this
3428 means replacing it with a suitably gimple STATEMENT_LIST. */
3431 gimplify_stmt (tree *stmt_p)
3433 gimplify_expr (stmt_p, NULL, NULL, is_gimple_stmt, fb_none);
3436 /* Similarly, but force the result to be a STATEMENT_LIST. */
3439 gimplify_to_stmt_list (tree *stmt_p)
3441 gimplify_stmt (stmt_p);
3443 *stmt_p = alloc_stmt_list ();
3444 else if (TREE_CODE (*stmt_p) != STATEMENT_LIST)
3447 *stmt_p = alloc_stmt_list ();
3448 append_to_statement_list (t, stmt_p);
3453 /* Gimplifies the expression tree pointed by EXPR_P. Return 0 if
3454 gimplification failed.
3456 PRE_P points to the list where side effects that must happen before
3457 EXPR should be stored.
3459 POST_P points to the list where side effects that must happen after
3460 EXPR should be stored, or NULL if there is no suitable list. In
3461 that case, we copy the result to a temporary, emit the
3462 post-effects, and then return the temporary.
3464 GIMPLE_TEST_F points to a function that takes a tree T and
3465 returns nonzero if T is in the GIMPLE form requested by the
3466 caller. The GIMPLE predicates are in tree-gimple.c.
3468 This test is used twice. Before gimplification, the test is
3469 invoked to determine whether *EXPR_P is already gimple enough. If
3470 that fails, *EXPR_P is gimplified according to its code and
3471 GIMPLE_TEST_F is called again. If the test still fails, then a new
3472 temporary variable is created and assigned the value of the
3473 gimplified expression.
3475 FALLBACK tells the function what sort of a temporary we want. If the 1
3476 bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK.
3477 If both are set, either is OK, but an lvalue is preferable.
3479 The return value is either GS_ERROR or GS_ALL_DONE, since this function
3480 iterates until solution. */
3482 enum gimplify_status
3483 gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
3484 bool (* gimple_test_f) (tree), fallback_t fallback)
3487 tree internal_pre = NULL_TREE;
3488 tree internal_post = NULL_TREE;
3490 int is_statement = (pre_p == NULL);
3491 location_t saved_location;
3492 enum gimplify_status ret;
3494 save_expr = *expr_p;
3495 if (save_expr == NULL_TREE)
3498 /* We used to check the predicate here and return immediately if it
3499 succeeds. This is wrong; the design is for gimplification to be
3500 idempotent, and for the predicates to only test for valid forms, not
3501 whether they are fully simplified. */
3503 /* Set up our internal queues if needed. */
3505 pre_p = &internal_pre;
3507 post_p = &internal_post;
3509 saved_location = input_location;
3510 if (save_expr != error_mark_node
3511 && EXPR_HAS_LOCATION (*expr_p))
3512 input_location = EXPR_LOCATION (*expr_p);
3514 /* Loop over the specific gimplifiers until the toplevel node
3515 remains the same. */
3518 /* Strip away as many useless type conversions as possible
3520 STRIP_USELESS_TYPE_CONVERSION (*expr_p);
3522 /* Remember the expr. */
3523 save_expr = *expr_p;
3525 /* Die, die, die, my darling. */
3526 if (save_expr == error_mark_node
3527 || (TREE_TYPE (save_expr)
3528 && TREE_TYPE (save_expr) == error_mark_node))
3534 /* Do any language-specific gimplification. */
3535 ret = lang_hooks.gimplify_expr (expr_p, pre_p, post_p);
3538 if (*expr_p == NULL_TREE)
3540 if (*expr_p != save_expr)
3543 else if (ret != GS_UNHANDLED)
3547 switch (TREE_CODE (*expr_p))
3549 /* First deal with the special cases. */
3551 case POSTINCREMENT_EXPR:
3552 case POSTDECREMENT_EXPR:
3553 case PREINCREMENT_EXPR:
3554 case PREDECREMENT_EXPR:
3555 ret = gimplify_self_mod_expr (expr_p, pre_p, post_p,
3556 fallback != fb_none);
3560 case ARRAY_RANGE_REF:
3564 case VIEW_CONVERT_EXPR:
3565 ret = gimplify_compound_lval (expr_p, pre_p, post_p,
3566 fallback ? fallback : fb_rvalue);
3570 ret = gimplify_cond_expr (expr_p, pre_p, NULL_TREE);
3574 ret = gimplify_call_expr (expr_p, pre_p, fallback != fb_none);
3581 ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none);
3586 ret = gimplify_modify_expr (expr_p, pre_p, post_p,
3587 fallback != fb_none);
3590 case TRUTH_ANDIF_EXPR:
3591 case TRUTH_ORIF_EXPR:
3592 ret = gimplify_boolean_expr (expr_p);
3595 case TRUTH_NOT_EXPR:
3596 TREE_OPERAND (*expr_p, 0)
3597 = gimple_boolify (TREE_OPERAND (*expr_p, 0));
3598 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3599 is_gimple_val, fb_rvalue);
3600 recalculate_side_effects (*expr_p);
3604 ret = gimplify_addr_expr (expr_p, pre_p, post_p);
3608 ret = gimplify_va_arg_expr (expr_p, pre_p, post_p);
3613 if (IS_EMPTY_STMT (*expr_p))
3619 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
3620 || fallback == fb_none)
3622 /* Just strip a conversion to void (or in void context) and
3624 *expr_p = TREE_OPERAND (*expr_p, 0);
3628 ret = gimplify_conversion (expr_p);
3629 if (ret == GS_ERROR)
3631 if (*expr_p != save_expr)
3635 case FIX_TRUNC_EXPR:
3637 case FIX_FLOOR_EXPR:
3638 case FIX_ROUND_EXPR:
3639 /* unary_expr: ... | '(' cast ')' val | ... */
3640 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3641 is_gimple_val, fb_rvalue);
3642 recalculate_side_effects (*expr_p);
3646 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3647 is_gimple_reg, fb_rvalue);
3648 recalculate_side_effects (*expr_p);
3651 /* Constants need not be gimplified. */
3661 /* If we require an lvalue, such as for ADDR_EXPR, retain the
3662 CONST_DECL node. Otherwise the decl is replacable by its
3664 /* ??? Should be == fb_lvalue, but ADDR_EXPR passes fb_either. */
3665 if (fallback & fb_lvalue)
3668 *expr_p = DECL_INITIAL (*expr_p);
3672 ret = gimplify_decl_expr (expr_p);
3676 /* FIXME make this a decl. */
3681 ret = gimplify_bind_expr (expr_p, NULL, pre_p);
3685 ret = gimplify_loop_expr (expr_p, pre_p);
3689 ret = gimplify_switch_expr (expr_p, pre_p);
3692 case LABELED_BLOCK_EXPR:
3693 ret = gimplify_labeled_block_expr (expr_p);
3696 case EXIT_BLOCK_EXPR:
3697 ret = gimplify_exit_block_expr (expr_p);
3701 ret = gimplify_exit_expr (expr_p);
3705 /* If the target is not LABEL, then it is a computed jump
3706 and the target needs to be gimplified. */
3707 if (TREE_CODE (GOTO_DESTINATION (*expr_p)) != LABEL_DECL)
3708 ret = gimplify_expr (&GOTO_DESTINATION (*expr_p), pre_p,
3709 NULL, is_gimple_val, fb_rvalue);
3714 #ifdef ENABLE_CHECKING
3715 if (decl_function_context (LABEL_EXPR_LABEL (*expr_p)) != current_function_decl)
3720 case CASE_LABEL_EXPR:
3721 ret = gimplify_case_label_expr (expr_p);
3725 ret = gimplify_return_expr (*expr_p, pre_p);
3729 /* Don't reduce this in place; let gimplify_init_constructor work its
3730 magic. Buf if we're just elaborating this for side effects, just
3731 gimplify any element that has side-effects. */
3732 if (fallback == fb_none)
3734 for (tmp = CONSTRUCTOR_ELTS (*expr_p); tmp;
3735 tmp = TREE_CHAIN (tmp))
3736 if (TREE_SIDE_EFFECTS (TREE_VALUE (tmp)))
3737 gimplify_expr (&TREE_VALUE (tmp), pre_p, post_p,
3738 gimple_test_f, fallback);
3740 *expr_p = NULL_TREE;
3746 /* The following are special cases that are not handled by the
3747 original GIMPLE grammar. */
3749 /* SAVE_EXPR nodes are converted into a GIMPLE identifier and
3752 ret = gimplify_save_expr (expr_p, pre_p, post_p);
3757 enum gimplify_status r0, r1, r2;
3759 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3760 is_gimple_lvalue, fb_either);
3761 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3762 is_gimple_val, fb_rvalue);
3763 r2 = gimplify_expr (&TREE_OPERAND (*expr_p, 2), pre_p, post_p,
3764 is_gimple_val, fb_rvalue);
3765 recalculate_side_effects (*expr_p);
3767 ret = MIN (r0, MIN (r1, r2));
3771 case NON_LVALUE_EXPR:
3772 /* This should have been stripped above. */
3777 ret = gimplify_asm_expr (expr_p, pre_p, post_p);
3780 case TRY_FINALLY_EXPR:
3781 case TRY_CATCH_EXPR:
3782 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 0));
3783 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 1));
3787 case CLEANUP_POINT_EXPR:
3788 ret = gimplify_cleanup_point_expr (expr_p, pre_p);
3792 ret = gimplify_target_expr (expr_p, pre_p, post_p);
3796 gimplify_to_stmt_list (&CATCH_BODY (*expr_p));
3800 case EH_FILTER_EXPR:
3801 gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p));
3807 enum gimplify_status r0, r1;
3808 r0 = gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p), pre_p, post_p,
3809 is_gimple_val, fb_rvalue);
3810 r1 = gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p), pre_p, post_p,
3811 is_gimple_val, fb_rvalue);
3817 /* We get here when taking the address of a label. We mark
3818 the label as "forced"; meaning it can never be removed and
3819 it is a potential target for any computed goto. */
3820 FORCED_LABEL (*expr_p) = 1;
3824 case STATEMENT_LIST:
3825 ret = gimplify_statement_list (expr_p);
3828 case WITH_SIZE_EXPR:
3830 enum gimplify_status r0, r1;
3831 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3832 post_p == &internal_post ? NULL : post_p,
3833 gimple_test_f, fallback);
3834 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3835 is_gimple_val, fb_rvalue);
3840 /* ??? If this is a local variable, and it has not been seen in any
3841 outer BIND_EXPR, then it's probably the result of a duplicate
3842 declaration, for which we've already issued an error. It would
3843 be really nice if the front end wouldn't leak these at all.
3844 Currently the only known culprit is C++ destructors, as seen
3845 in g++.old-deja/g++.jason/binding.C. */
3847 if (!TREE_STATIC (tmp) && !DECL_EXTERNAL (tmp)
3848 && decl_function_context (tmp) == current_function_decl
3849 && !DECL_SEEN_IN_BIND_EXPR_P (tmp))
3851 #ifdef ENABLE_CHECKING
3852 if (!errorcount && !sorrycount)
3859 /* If this is a local variable sized decl, it must be accessed
3860 indirectly. Perform that substitution. */
3861 if (DECL_VALUE_EXPR (tmp))
3863 *expr_p = unshare_expr (DECL_VALUE_EXPR (tmp));
3872 /* Allow callbacks into the gimplifier during optimization. */
3877 /* If this is a comparison of objects of aggregate type, handle
3878 it specially (by converting to a call to memcmp). It would be
3879 nice to only have to do this for variable-sized objects, but
3880 then we'd have to allow the same nest of reference nodes we
3881 allow for MODIFY_EXPR and that's too complex. */
3882 if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3883 && (AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 1)))))
3884 ret = gimplify_variable_sized_compare (expr_p);
3886 /* If *EXPR_P does not need to be special-cased, handle it
3887 according to its class. */
3888 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '1')
3889 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3890 post_p, is_gimple_val, fb_rvalue);
3891 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '2'
3892 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3893 || TREE_CODE (*expr_p) == TRUTH_AND_EXPR
3894 || TREE_CODE (*expr_p) == TRUTH_OR_EXPR
3895 || TREE_CODE (*expr_p) == TRUTH_XOR_EXPR)
3897 enum gimplify_status r0, r1;
3899 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3900 post_p, is_gimple_val, fb_rvalue);
3901 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p,
3902 post_p, is_gimple_val, fb_rvalue);
3906 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'd'
3907 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'c')
3913 /* Fail if we don't know how to handle this tree code. */
3916 recalculate_side_effects (*expr_p);
3920 /* If we replaced *expr_p, gimplify again. */
3921 if (ret == GS_OK && (*expr_p == NULL || *expr_p == save_expr))
3924 while (ret == GS_OK);
3926 /* If we encountered an error_mark somewhere nested inside, either
3927 stub out the statement or propagate the error back out. */
3928 if (ret == GS_ERROR)
3935 #ifdef ENABLE_CHECKING
3936 /* This was only valid as a return value from the langhook, which
3937 we handled. Make sure it doesn't escape from any other context. */
3938 if (ret == GS_UNHANDLED)
3942 if (fallback == fb_none && *expr_p && !is_gimple_stmt (*expr_p))
3944 /* We aren't looking for a value, and we don't have a valid
3945 statement. If it doesn't have side-effects, throw it away. */
3946 if (!TREE_SIDE_EFFECTS (*expr_p))
3948 else if (!TREE_THIS_VOLATILE (*expr_p))
3950 /* This is probably a _REF that contains something nested that
3951 has side effects. Recurse through the operands to find it. */
3952 enum tree_code code = TREE_CODE (*expr_p);
3954 if (code == COMPONENT_REF
3955 || code == REALPART_EXPR || code == IMAGPART_EXPR)
3956 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3957 gimple_test_f, fallback);
3958 else if (code == ARRAY_REF || code == ARRAY_RANGE_REF)
3960 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3961 gimple_test_f, fallback);
3962 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3963 gimple_test_f, fallback);
3966 /* Anything else with side-effects
3967 must be converted to a valid statement before we get here. */
3972 else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p)))
3974 /* Historically, the compiler has treated a bare
3975 reference to a volatile lvalue as forcing a load. */
3976 tree tmp = create_tmp_var (TREE_TYPE (*expr_p), "vol");
3977 *expr_p = build (MODIFY_EXPR, TREE_TYPE (tmp), tmp, *expr_p);
3980 /* We can't do anything useful with a volatile reference to
3981 incomplete type, so just throw it away. */
3985 /* If we are gimplifying at the statement level, we're done. Tack
3986 everything together and replace the original statement with the
3988 if (fallback == fb_none || is_statement)
3990 if (internal_pre || internal_post)
3992 append_to_statement_list (*expr_p, &internal_pre);
3993 append_to_statement_list (internal_post, &internal_pre);
3994 annotate_all_with_locus (&internal_pre, input_location);
3995 *expr_p = internal_pre;
3999 else if (TREE_CODE (*expr_p) == STATEMENT_LIST)
4000 annotate_all_with_locus (expr_p, input_location);
4002 annotate_one_with_locus (*expr_p, input_location);
4006 /* Otherwise we're gimplifying a subexpression, so the resulting value is
4009 /* If it's sufficiently simple already, we're done. Unless we are
4010 handling some post-effects internally; if that's the case, we need to
4011 copy into a temp before adding the post-effects to the tree. */
4012 if (!internal_post && (*gimple_test_f) (*expr_p))
4015 /* Otherwise, we need to create a new temporary for the gimplified
4018 /* We can't return an lvalue if we have an internal postqueue. The
4019 object the lvalue refers to would (probably) be modified by the
4020 postqueue; we need to copy the value out first, which means an
4022 if ((fallback & fb_lvalue) && !internal_post
4023 && is_gimple_addressable (*expr_p))
4025 /* An lvalue will do. Take the address of the expression, store it
4026 in a temporary, and replace the expression with an INDIRECT_REF of
4028 tmp = build_fold_addr_expr (*expr_p);
4029 gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue);
4030 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp);
4032 else if ((fallback & fb_rvalue) && is_gimple_formal_tmp_rhs (*expr_p))
4034 #if defined ENABLE_CHECKING
4035 if (VOID_TYPE_P (TREE_TYPE (*expr_p)))
4039 /* An rvalue will do. Assign the gimplified expression into a new
4040 temporary TMP and replace the original expression with TMP. */
4042 if (internal_post || (fallback & fb_lvalue))
4043 /* The postqueue might change the value of the expression between
4044 the initialization and use of the temporary, so we can't use a
4045 formal temp. FIXME do we care? */
4046 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
4048 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
4049 DECL_GIMPLE_FORMAL_TEMP_P (*expr_p) = 1;
4051 else if (fallback & fb_mayfail)
4053 /* If this is an asm statement, and the user asked for the impossible,
4054 don't abort. Fail and let gimplify_asm_expr issue an error. */
4060 fprintf (stderr, "gimplification failed:\n");
4061 print_generic_expr (stderr, *expr_p, 0);
4062 debug_tree (*expr_p);
4066 #if defined ENABLE_CHECKING
4067 /* Make sure the temporary matches our predicate. */
4068 if (!(*gimple_test_f) (*expr_p))
4074 annotate_all_with_locus (&internal_post, input_location);
4075 append_to_statement_list (internal_post, pre_p);
4079 input_location = saved_location;
4083 /* Look through TYPE for variable-sized objects and gimplify each such
4084 size that we find. Add to LIST_P any statements generated. */
4087 gimplify_type_sizes (tree type, tree *list_p)
4091 switch (TREE_CODE (type))
4101 gimplify_one_sizepos (&TYPE_MIN_VALUE (type), list_p);
4102 gimplify_one_sizepos (&TYPE_MAX_VALUE (type), list_p);
4106 /* These anonymous types don't have declarations, so handle them here. */
4107 gimplify_type_sizes (TYPE_DOMAIN (type), list_p);
4112 case QUAL_UNION_TYPE:
4113 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4114 if (TREE_CODE (field) == FIELD_DECL)
4115 gimplify_one_sizepos (&DECL_FIELD_OFFSET (field), list_p);
4122 gimplify_one_sizepos (&TYPE_SIZE (type), list_p);
4123 gimplify_one_sizepos (&TYPE_SIZE_UNIT (type), list_p);
4126 /* Subroutine of the above to gimplify one size or position, *EXPR_P.
4127 We add any required statements to STMT_P. */
4130 gimplify_one_sizepos (tree *expr_p, tree *stmt_p)
4132 /* We don't do anything if the value isn't there, is constant, or contains
4133 A PLACEHOLDER_EXPR. We also don't want to do anything if it's already
4134 a VAR_DECL. If it's a VAR_DECL from another function, the gimplfier
4135 will want to replace it with a new variable, but that will cause problems
4136 if this type is from outside the function. It's OK to have that here. */
4137 if (*expr_p == NULL_TREE || TREE_CONSTANT (*expr_p)
4138 || TREE_CODE (*expr_p) == VAR_DECL
4139 || CONTAINS_PLACEHOLDER_P (*expr_p))
4142 gimplify_expr (expr_p, stmt_p, NULL, is_gimple_val, fb_rvalue);
4145 #ifdef ENABLE_CHECKING
4146 /* Compare types A and B for a "close enough" match. */
4149 cpt_same_type (tree a, tree b)
4151 if (lang_hooks.types_compatible_p (a, b))
4154 /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't
4155 link them together. This routine is intended to catch type errors
4156 that will affect the optimizers, and the optimizers don't add new
4157 dereferences of function pointers, so ignore it. */
4158 if ((TREE_CODE (a) == FUNCTION_TYPE || TREE_CODE (a) == METHOD_TYPE)
4159 && (TREE_CODE (b) == FUNCTION_TYPE || TREE_CODE (b) == METHOD_TYPE))
4162 /* ??? The C FE pushes type qualifiers after the fact into the type of
4163 the element from the type of the array. See build_unary_op's handling
4164 of ADDR_EXPR. This seems wrong -- if we were going to do this, we
4165 should have done it when creating the variable in the first place.
4166 Alternately, why aren't the two array types made variants? */
4167 if (TREE_CODE (a) == ARRAY_TYPE && TREE_CODE (b) == ARRAY_TYPE)
4168 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4170 /* And because of those, we have to recurse down through pointers. */
4171 if (POINTER_TYPE_P (a) && POINTER_TYPE_P (b))
4172 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4177 /* Check for some cases of the front end missing cast expressions.
4178 The type of a dereference should correspond to the pointer type;
4179 similarly the type of an address should match its object. */
4182 check_pointer_types_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
4183 void *data ATTRIBUTE_UNUSED)
4186 tree ptype, otype, dtype;
4188 switch (TREE_CODE (t))
4192 otype = TREE_TYPE (t);
4193 ptype = TREE_TYPE (TREE_OPERAND (t, 0));
4194 dtype = TREE_TYPE (ptype);
4195 if (!cpt_same_type (otype, dtype))
4200 ptype = TREE_TYPE (t);
4201 otype = TREE_TYPE (TREE_OPERAND (t, 0));
4202 dtype = TREE_TYPE (ptype);
4203 if (!cpt_same_type (otype, dtype))
4205 /* &array is allowed to produce a pointer to the element, rather than
4206 a pointer to the array type. We must allow this in order to
4207 properly represent assigning the address of an array in C into
4208 pointer to the element type. */
4209 if (TREE_CODE (otype) == ARRAY_TYPE
4210 && POINTER_TYPE_P (ptype)
4211 && cpt_same_type (TREE_TYPE (otype), dtype))
4226 /* Gimplify the body of statements pointed by BODY_P. FNDECL is the
4227 function decl containing BODY. */
4230 gimplify_body (tree *body_p, tree fndecl)
4232 location_t saved_location = input_location;
4235 timevar_push (TV_TREE_GIMPLIFY);
4236 push_gimplify_context ();
4238 /* Unshare most shared trees in the body and in that of any nested functions.
4239 It would seem we don't have to do this for nested functions because
4240 they are supposed to be output and then the outer function gimplified
4241 first, but the g++ front end doesn't always do it that way. */
4242 unshare_body (body_p, fndecl);
4243 unvisit_body (body_p, fndecl);
4245 /* Make sure input_location isn't set to something wierd. */
4246 input_location = DECL_SOURCE_LOCATION (fndecl);
4248 /* Gimplify the function's body. */
4249 gimplify_stmt (body_p);
4252 /* Unshare again, in case gimplification was sloppy. */
4253 unshare_all_trees (body);
4256 body = alloc_stmt_list ();
4257 else if (TREE_CODE (body) == STATEMENT_LIST)
4259 tree t = expr_only (*body_p);
4264 /* If there isn't an outer BIND_EXPR, add one. */
4265 if (TREE_CODE (body) != BIND_EXPR)
4267 tree b = build (BIND_EXPR, void_type_node, NULL_TREE,
4268 NULL_TREE, NULL_TREE);
4269 TREE_SIDE_EFFECTS (b) = 1;
4270 append_to_statement_list_force (body, &BIND_EXPR_BODY (b));
4275 pop_gimplify_context (body);
4277 #ifdef ENABLE_CHECKING
4278 walk_tree (body_p, check_pointer_types_r, NULL, NULL);
4281 timevar_pop (TV_TREE_GIMPLIFY);
4282 input_location = saved_location;
4285 /* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL
4286 node for the function we want to gimplify. */
4289 gimplify_function_tree (tree fndecl)
4293 oldfn = current_function_decl;
4294 current_function_decl = fndecl;
4296 gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl);
4298 /* If we're instrumenting function entry/exit, then prepend the call to
4299 the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
4300 catch the exit hook. */
4301 /* ??? Add some way to ignore exceptions for this TFE. */
4302 if (flag_instrument_function_entry_exit
4303 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl))
4307 tf = build (TRY_FINALLY_EXPR, void_type_node, NULL, NULL);
4308 TREE_SIDE_EFFECTS (tf) = 1;
4309 x = DECL_SAVED_TREE (fndecl);
4310 append_to_statement_list (x, &TREE_OPERAND (tf, 0));
4311 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_EXIT];
4312 x = build_function_call_expr (x, NULL);
4313 append_to_statement_list (x, &TREE_OPERAND (tf, 1));
4315 bind = build (BIND_EXPR, void_type_node, NULL, NULL, NULL);
4316 TREE_SIDE_EFFECTS (bind) = 1;
4317 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_ENTER];
4318 x = build_function_call_expr (x, NULL);
4319 append_to_statement_list (x, &BIND_EXPR_BODY (bind));
4320 append_to_statement_list (tf, &BIND_EXPR_BODY (bind));
4322 DECL_SAVED_TREE (fndecl) = bind;
4325 current_function_decl = oldfn;
4328 #include "gt-gimplify.h"