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 hashval_t gimple_tree_hash (const void *);
76 static int gimple_tree_eq (const void *, const void *);
77 static bool gimple_conditional_context (void);
78 static void gimple_push_condition (void);
79 static void gimple_pop_condition (tree *);
80 static void append_to_statement_list_1 (tree, tree *, bool);
81 static inline void remove_suffix (char *, int);
82 static inline tree create_tmp_from_val (tree);
83 static tree lookup_tmp_var (tree, bool);
84 static tree internal_get_tmp_var (tree, tree *, tree *, bool);
85 static bool should_carry_locus_p (tree);
86 static tree mostly_copy_tree_r (tree *, int *, void *);
87 static tree mark_decls_volatile_r (tree *, int *, void *);
88 static tree copy_if_shared_r (tree *, int *, void *);
89 static tree unmark_visited_r (tree *, int *, void *);
90 static void unshare_body (tree *, tree);
91 static void unvisit_body (tree *, tree);
92 static void build_stack_save_restore (tree *, tree *);
93 static enum gimplify_status gimplify_bind_expr (tree *, tree, tree *);
94 static enum gimplify_status gimplify_return_expr (tree, tree *);
95 static enum gimplify_status gimplify_loop_expr (tree *, tree *);
96 static int compare_case_labels (const void *, const void *);
97 static enum gimplify_status gimplify_switch_expr (tree *, tree *);
98 static enum gimplify_status gimplify_case_label_expr (tree *);
99 static enum gimplify_status gimplify_labeled_block_expr (tree *);
100 static enum gimplify_status gimplify_exit_block_expr (tree *);
101 static enum gimplify_status gimplify_exit_expr (tree *);
102 static enum gimplify_status gimplify_init_constructor (tree *, tree *, tree *,
104 static void canonicalize_component_ref (tree *);
105 static void canonicalize_addr_expr (tree *);
106 static enum gimplify_status gimplify_conversion (tree *);
107 static enum gimplify_status gimplify_minimax_expr (tree *, tree *, tree *);
108 static enum gimplify_status gimplify_array_ref_to_plus (tree *, tree *,
110 static tree build_addr_expr_with_type (tree, tree);
111 static tree build_addr_expr (tree);
112 static enum gimplify_status gimplify_compound_lval (tree *, tree *, tree *,
114 static enum gimplify_status gimplify_self_mod_expr (tree *, tree *, tree *,
116 static enum gimplify_status gimplify_call_expr (tree *, tree *,
118 static tree shortcut_cond_r (tree, tree *, tree *);
119 static tree shortcut_cond_expr (tree);
120 static tree gimple_boolify (tree);
121 static enum gimplify_status gimplify_cond_expr (tree *, tree *, tree);
122 static enum gimplify_status gimplify_modify_expr (tree *, tree *, tree *,
124 static enum gimplify_status gimplify_modify_expr_rhs (tree *, tree *, tree *,
125 tree *, tree *, bool);
126 static enum gimplify_status gimplify_variable_sized_compare (tree *);
127 static enum gimplify_status gimplify_boolean_expr (tree *);
128 static enum gimplify_status gimplify_compound_expr (tree *, tree *, bool);
129 static enum gimplify_status gimplify_statement_list (tree *);
130 static enum gimplify_status gimplify_save_expr (tree *, tree *, tree *);
131 static enum gimplify_status gimplify_addr_expr (tree *, tree *, tree *);
132 static enum gimplify_status gimplify_asm_expr (tree *, tree *, tree *);
133 static enum gimplify_status gimplify_cleanup_point_expr (tree *, tree *);
134 static void gimple_push_cleanup (tree, tree, tree *);
135 static enum gimplify_status gimplify_target_expr (tree *, tree *, tree *);
136 #ifdef ENABLE_CHECKING
137 static bool cpt_same_type (tree, tree);
138 static tree check_pointer_types_r (tree *, int *, void *);
141 /* Return a hash value for a formal temporary table entry. */
144 gimple_tree_hash (const void *p)
146 tree t = ((const elt_t *)p)->val;
147 return iterative_hash_expr (t, 0);
150 /* Compare two formal temporary table entries. */
153 gimple_tree_eq (const void *p1, const void *p2)
155 tree t1 = ((const elt_t *)p1)->val;
156 tree t2 = ((const elt_t *)p2)->val;
157 enum tree_code code = TREE_CODE (t1);
159 if (TREE_CODE (t2) != code
160 || TREE_TYPE (t1) != TREE_TYPE (t2))
163 if (!operand_equal_p (t1, t2, 0))
166 /* Only allow them to compare equal if they also hash equal; otherwise
167 results are nondeterminate, and we fail bootstrap comparison. */
168 if (gimple_tree_hash (p1) != gimple_tree_hash (p2))
174 /* Set up a context for the gimplifier. */
177 push_gimplify_context (void)
182 = (struct gimplify_ctx *) xcalloc (1, sizeof (struct gimplify_ctx));
183 gimplify_ctxp->temp_htab
184 = htab_create (1000, gimple_tree_hash, gimple_tree_eq, free);
187 /* Tear down a context for the gimplifier. If BODY is non-null, then
188 put the temporaries into the outer BIND_EXPR. Otherwise, put them
189 in the unexpanded_var_list. */
192 pop_gimplify_context (tree body)
194 if (!gimplify_ctxp || gimplify_ctxp->current_bind_expr)
198 declare_tmp_vars (gimplify_ctxp->temps, body);
200 record_vars (gimplify_ctxp->temps);
204 fprintf (stderr, " collisions: %f ",
205 htab_collisions (gimplify_ctxp->temp_htab));
208 htab_delete (gimplify_ctxp->temp_htab);
209 free (gimplify_ctxp);
210 gimplify_ctxp = NULL;
214 gimple_push_bind_expr (tree bind)
216 TREE_CHAIN (bind) = gimplify_ctxp->current_bind_expr;
217 gimplify_ctxp->current_bind_expr = bind;
221 gimple_pop_bind_expr (void)
223 gimplify_ctxp->current_bind_expr
224 = TREE_CHAIN (gimplify_ctxp->current_bind_expr);
228 gimple_current_bind_expr (void)
230 return gimplify_ctxp->current_bind_expr;
233 /* Returns true iff there is a COND_EXPR between us and the innermost
234 CLEANUP_POINT_EXPR. This info is used by gimple_push_cleanup. */
237 gimple_conditional_context (void)
239 return gimplify_ctxp->conditions > 0;
242 /* Note that we've entered a COND_EXPR. */
245 gimple_push_condition (void)
247 ++(gimplify_ctxp->conditions);
250 /* Note that we've left a COND_EXPR. If we're back at unconditional scope
251 now, add any conditional cleanups we've seen to the prequeue. */
254 gimple_pop_condition (tree *pre_p)
256 int conds = --(gimplify_ctxp->conditions);
259 append_to_statement_list (gimplify_ctxp->conditional_cleanups, pre_p);
260 gimplify_ctxp->conditional_cleanups = NULL_TREE;
266 /* A subroutine of append_to_statement_list{,_force}. */
269 append_to_statement_list_1 (tree t, tree *list_p, bool side_effects)
272 tree_stmt_iterator i;
279 if (t && TREE_CODE (t) == STATEMENT_LIST)
284 *list_p = list = alloc_stmt_list ();
288 tsi_link_after (&i, t, TSI_CONTINUE_LINKING);
291 /* Add T to the end of the list container pointed by LIST_P.
292 If T is an expression with no effects, it is ignored. */
295 append_to_statement_list (tree t, tree *list_p)
297 append_to_statement_list_1 (t, list_p, t ? TREE_SIDE_EFFECTS (t) : false);
300 /* Similar, but the statement is always added, regardless of side effects. */
303 append_to_statement_list_force (tree t, tree *list_p)
305 append_to_statement_list_1 (t, list_p, t != NULL);
308 /* Both gimplify the statement T and append it to LIST_P. */
311 gimplify_and_add (tree t, tree *list_p)
314 append_to_statement_list (t, list_p);
317 /* Add T to the end of a COMPOUND_EXPR pointed by LIST_P. The type
318 of the result is the type of T. */
321 append_to_compound_expr (tree t, tree *list_p)
328 *list_p = build (COMPOUND_EXPR, TREE_TYPE (t), *list_p, t);
331 /* Strip off a legitimate source ending from the input string NAME of
332 length LEN. Rather than having to know the names used by all of
333 our front ends, we strip off an ending of a period followed by
334 up to five characters. (Java uses ".class".) */
337 remove_suffix (char *name, int len)
341 for (i = 2; i < 8 && len > i; i++)
343 if (name[len - i] == '.')
345 name[len - i] = '\0';
351 /* Create a nameless artificial label and put it in the current function
352 context. Returns the newly created label. */
355 create_artificial_label (void)
357 tree lab = build_decl (LABEL_DECL, NULL_TREE, void_type_node);
358 DECL_ARTIFICIAL (lab) = 1;
359 DECL_CONTEXT (lab) = current_function_decl;
363 /* Create a new temporary name with PREFIX. Returns an identifier. */
365 static GTY(()) unsigned int tmp_var_id_num;
368 create_tmp_var_name (const char *prefix)
374 char *preftmp = ASTRDUP (prefix);
375 remove_suffix (preftmp, strlen (preftmp));
379 ASM_FORMAT_PRIVATE_NAME (tmp_name, prefix ? prefix : "T", tmp_var_id_num++);
380 return get_identifier (tmp_name);
384 /* Create a new temporary variable declaration of type TYPE.
385 Does NOT push it into the current binding. */
388 create_tmp_var_raw (tree type, const char *prefix)
393 /* Make the type of the variable writable. */
394 new_type = build_type_variant (type, 0, 0);
395 TYPE_ATTRIBUTES (new_type) = TYPE_ATTRIBUTES (type);
397 tmp_var = build_decl (VAR_DECL, create_tmp_var_name (prefix), type);
399 /* The variable was declared by the compiler. */
400 DECL_ARTIFICIAL (tmp_var) = 1;
401 /* And we don't want debug info for it. */
402 DECL_IGNORED_P (tmp_var) = 1;
404 /* Make the variable writable. */
405 TREE_READONLY (tmp_var) = 0;
407 DECL_EXTERNAL (tmp_var) = 0;
408 TREE_STATIC (tmp_var) = 0;
409 TREE_USED (tmp_var) = 1;
414 /* Create a new temporary variable declaration of type TYPE. DOES push the
415 variable into the current binding. Further, assume that this is called
416 only from gimplification or optimization, at which point the creation of
417 certain types are bugs. */
420 create_tmp_var (tree type, const char *prefix)
424 #if defined ENABLE_CHECKING
425 /* We don't allow types that are addressable (meaning we can't make copies),
426 incomplete, or of variable size. */
427 if (TREE_ADDRESSABLE (type)
428 || !COMPLETE_TYPE_P (type)
429 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST)
433 tmp_var = create_tmp_var_raw (type, prefix);
434 gimple_add_tmp_var (tmp_var);
438 /* Given a tree, try to return a useful variable name that we can use
439 to prefix a temporary that is being assigned the value of the tree.
440 I.E. given <temp> = &A, return A. */
448 STRIP_NOPS (stripped_decl);
449 if (DECL_P (stripped_decl) && DECL_NAME (stripped_decl))
450 return IDENTIFIER_POINTER (DECL_NAME (stripped_decl));
453 switch (TREE_CODE (stripped_decl))
456 return get_name (TREE_OPERAND (stripped_decl, 0));
464 /* Create a temporary with a name derived from VAL. Subroutine of
465 lookup_tmp_var; nobody else should call this function. */
468 create_tmp_from_val (tree val)
470 return create_tmp_var (TREE_TYPE (val), get_name (val));
473 /* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse
474 an existing expression temporary. */
477 lookup_tmp_var (tree val, bool is_formal)
479 if (!is_formal || TREE_SIDE_EFFECTS (val))
480 return create_tmp_from_val (val);
487 slot = htab_find_slot (gimplify_ctxp->temp_htab, (void *)&elt, INSERT);
490 elt_p = xmalloc (sizeof (*elt_p));
492 elt_p->temp = create_tmp_from_val (val);
493 *slot = (void *)elt_p;
496 elt_p = (elt_t *) *slot;
502 /* Returns a formal temporary variable initialized with VAL. PRE_P is as
503 in gimplify_expr. Only use this function if:
505 1) The value of the unfactored expression represented by VAL will not
506 change between the initialization and use of the temporary, and
507 2) The temporary will not be otherwise modified.
509 For instance, #1 means that this is inappropriate for SAVE_EXPR temps,
510 and #2 means it is inappropriate for && temps.
512 For other cases, use get_initialized_tmp_var instead. */
515 internal_get_tmp_var (tree val, tree *pre_p, tree *post_p, bool is_formal)
520 gimplify_expr (&val, pre_p, post_p, is_gimple_rhs, fb_rvalue);
522 t = lookup_tmp_var (val, is_formal);
524 mod = build (MODIFY_EXPR, TREE_TYPE (t), t, val);
526 class = TREE_CODE_CLASS (TREE_CODE (val));
527 if (EXPR_LOCUS (val))
528 SET_EXPR_LOCUS (mod, EXPR_LOCUS (val));
530 annotate_with_locus (mod, input_location);
531 /* gimplify_modify_expr might want to reduce this further. */
532 gimplify_stmt (&mod);
533 append_to_statement_list (mod, pre_p);
539 get_formal_tmp_var (tree val, tree *pre_p)
541 return internal_get_tmp_var (val, pre_p, NULL, true);
544 /* Returns a temporary variable initialized with VAL. PRE_P and POST_P
545 are as in gimplify_expr. */
548 get_initialized_tmp_var (tree val, tree *pre_p, tree *post_p)
550 return internal_get_tmp_var (val, pre_p, post_p, false);
553 /* Returns true if T is a GIMPLE temporary variable, false otherwise. */
556 is_gimple_tmp_var (tree t)
558 /* FIXME this could trigger for other local artificials, too. */
559 return (TREE_CODE (t) == VAR_DECL && DECL_ARTIFICIAL (t)
560 && !TREE_STATIC (t) && !DECL_EXTERNAL (t));
563 /* Declares all the variables in VARS in SCOPE. Returns the last
564 DECL_STMT emitted. */
567 declare_tmp_vars (tree vars, tree scope)
574 /* C99 mode puts the default 'return 0;' for main() outside the outer
575 braces. So drill down until we find an actual scope. */
576 while (TREE_CODE (scope) == COMPOUND_EXPR)
577 scope = TREE_OPERAND (scope, 0);
579 if (TREE_CODE (scope) != BIND_EXPR)
582 temps = nreverse (last);
583 TREE_CHAIN (last) = BIND_EXPR_VARS (scope);
584 BIND_EXPR_VARS (scope) = temps;
586 /* We don't add the temps to the block for this BIND_EXPR, as we're
587 not interested in debugging info for them. */
592 gimple_add_tmp_var (tree tmp)
594 if (TREE_CHAIN (tmp) || tmp->decl.seen_in_bind_expr)
597 DECL_CONTEXT (tmp) = current_function_decl;
598 tmp->decl.seen_in_bind_expr = 1;
602 TREE_CHAIN (tmp) = gimplify_ctxp->temps;
603 gimplify_ctxp->temps = tmp;
608 declare_tmp_vars (tmp, DECL_SAVED_TREE (current_function_decl));
611 /* Determines whether to assign a locus to the statement STMT. */
614 should_carry_locus_p (tree stmt)
616 /* Don't emit a line note for a label. We particularly don't want to
617 emit one for the break label, since it doesn't actually correspond
618 to the beginning of the loop/switch. */
619 if (TREE_CODE (stmt) == LABEL_EXPR)
622 /* Do not annotate empty statements, since it confuses gcov. */
623 if (!TREE_SIDE_EFFECTS (stmt))
630 annotate_one_with_locus (tree t, location_t locus)
632 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (t)))
633 && ! EXPR_HAS_LOCATION (t)
634 && should_carry_locus_p (t))
635 annotate_with_locus (t, locus);
639 annotate_all_with_locus (tree *stmt_p, location_t locus)
641 tree_stmt_iterator i;
646 for (i = tsi_start (*stmt_p); !tsi_end_p (i); tsi_next (&i))
648 tree t = tsi_stmt (i);
650 #ifdef ENABLE_CHECKING
651 /* Assuming we've already been gimplified, we shouldn't
652 see nested chaining constructs anymore. */
653 if (TREE_CODE (t) == STATEMENT_LIST
654 || TREE_CODE (t) == COMPOUND_EXPR)
658 annotate_one_with_locus (t, locus);
662 /* Similar to copy_tree_r() but do not copy SAVE_EXPR or TARGET_EXPR nodes.
663 These nodes model computations that should only be done once. If we
664 were to unshare something like SAVE_EXPR(i++), the gimplification
665 process would create wrong code. */
668 mostly_copy_tree_r (tree *tp, int *walk_subtrees, void *data)
670 enum tree_code code = TREE_CODE (*tp);
671 /* Don't unshare types, decls, constants and SAVE_EXPR nodes. */
672 if (TREE_CODE_CLASS (code) == 't'
673 || TREE_CODE_CLASS (code) == 'd'
674 || TREE_CODE_CLASS (code) == 'c'
675 || code == SAVE_EXPR || code == TARGET_EXPR
676 /* We can't do anything sensible with a BLOCK used as an expression,
677 but we also can't abort when we see it because of non-expression
678 uses. So just avert our eyes and cross our fingers. Silly Java. */
681 else if (code == BIND_EXPR)
684 copy_tree_r (tp, walk_subtrees, data);
689 /* Mark all the _DECL nodes under *TP as volatile. FIXME: This must die
690 after VA_ARG_EXPRs are properly lowered. */
693 mark_decls_volatile_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
694 void *data ATTRIBUTE_UNUSED)
697 TREE_THIS_VOLATILE (*tp) = 1;
703 /* Callback for walk_tree to unshare most of the shared trees rooted at
704 *TP. If *TP has been visited already (i.e., TREE_VISITED (*TP) == 1),
705 then *TP is deep copied by calling copy_tree_r.
707 This unshares the same trees as copy_tree_r with the exception of
708 SAVE_EXPR nodes. These nodes model computations that should only be
709 done once. If we were to unshare something like SAVE_EXPR(i++), the
710 gimplification process would create wrong code. */
713 copy_if_shared_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
714 void *data ATTRIBUTE_UNUSED)
717 enum tree_code code = TREE_CODE (t);
719 /* Skip types, decls, and constants. But we do want to look at their
720 types and the bounds of types. Mark them as visited so we properly
721 unmark their subtrees on the unmark pass. If we've already seen them,
722 don't look down further. */
723 if (TREE_CODE_CLASS (code) == 't'
724 || TREE_CODE_CLASS (code) == 'd'
725 || TREE_CODE_CLASS (code) == 'c')
727 if (TREE_VISITED (t))
730 TREE_VISITED (t) = 1;
733 /* Special-case BIND_EXPR. We should never be copying these, therefore
734 we can omit examining BIND_EXPR_VARS. Which also avoids problems with
735 double processing of the DECL_INITIAL, which could be seen via both
736 the BIND_EXPR_VARS and a DECL_STMT. */
737 else if (code == BIND_EXPR)
739 if (TREE_VISITED (t))
741 TREE_VISITED (t) = 1;
743 walk_tree (&BIND_EXPR_BODY (t), copy_if_shared_r, NULL, NULL);
746 /* If this node has been visited already, unshare it and don't look
748 else if (TREE_VISITED (t))
750 walk_tree (tp, mostly_copy_tree_r, NULL, NULL);
754 /* Otherwise, mark the tree as visited and keep looking. */
757 TREE_VISITED (t) = 1;
758 if (TREE_CODE (*tp) == VA_ARG_EXPR
759 && targetm.calls.gimplify_va_arg_expr == NULL)
761 /* Mark any _DECL inside the operand as volatile to avoid
762 the optimizers messing around with it. We have to do this
763 early, otherwise we might mark a variable as volatile
764 after we gimplify other statements that use the variable
765 assuming it's not volatile. */
767 /* FIXME once most targets define the above hook, this should
768 go away (perhaps along with the #include "target.h"). */
769 walk_tree (&TREE_OPERAND (*tp, 0), mark_decls_volatile_r,
778 unmark_visited_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
779 void *data ATTRIBUTE_UNUSED)
781 if (TREE_VISITED (*tp))
782 TREE_VISITED (*tp) = 0;
789 /* Unshare all the trees in BODY_P, a pointer to the body of FNDECL, and the
790 bodies of any nested functions. */
793 unshare_body (tree *body_p, tree fndecl)
795 struct cgraph_node *cgn = cgraph_node (fndecl);
797 walk_tree (body_p, copy_if_shared_r, NULL, NULL);
798 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
799 unshare_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
802 /* Likewise, but mark all trees as not visited. */
805 unvisit_body (tree *body_p, tree fndecl)
807 struct cgraph_node *cgn = cgraph_node (fndecl);
809 walk_tree (body_p, unmark_visited_r, NULL, NULL);
810 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
811 unvisit_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
814 /* Unshare T and all the trees reached from T via TREE_CHAIN. */
817 unshare_all_trees (tree t)
819 walk_tree (&t, copy_if_shared_r, NULL, NULL);
820 walk_tree (&t, unmark_visited_r, NULL, NULL);
823 /* Unconditionally make an unshared copy of EXPR. This is used when using
824 stored expressions which span multiple functions, such as BINFO_VTABLE,
825 as the normal unsharing process can't tell that they're shared. */
828 unshare_expr (tree expr)
830 walk_tree (&expr, mostly_copy_tree_r, NULL, NULL);
834 /* A terser interface for building a representation of a exception
838 gimple_build_eh_filter (tree body, tree allowed, tree failure)
842 /* FIXME should the allowed types go in TREE_TYPE? */
843 t = build (EH_FILTER_EXPR, void_type_node, allowed, NULL_TREE);
844 append_to_statement_list (failure, &EH_FILTER_FAILURE (t));
846 t = build (TRY_CATCH_EXPR, void_type_node, NULL_TREE, t);
847 append_to_statement_list (body, &TREE_OPERAND (t, 0));
853 /* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
854 contain statements and have a value. Assign its value to a temporary
855 and give it void_type_node. Returns the temporary, or NULL_TREE if
856 WRAPPER was already void. */
859 voidify_wrapper_expr (tree wrapper, tree temp)
861 if (!VOID_TYPE_P (TREE_TYPE (wrapper)))
863 tree *p, sub = wrapper;
866 /* Set p to point to the body of the wrapper. */
867 switch (TREE_CODE (sub))
870 /* For a BIND_EXPR, the body is operand 1. */
871 p = &BIND_EXPR_BODY (sub);
875 p = &TREE_OPERAND (sub, 0);
879 /* Advance to the last statement. Set all container types to void. */
880 if (TREE_CODE (*p) == STATEMENT_LIST)
882 tree_stmt_iterator i = tsi_last (*p);
883 p = tsi_end_p (i) ? NULL : tsi_stmt_ptr (i);
887 for (; TREE_CODE (*p) == COMPOUND_EXPR; p = &TREE_OPERAND (*p, 1))
889 TREE_SIDE_EFFECTS (*p) = 1;
890 TREE_TYPE (*p) = void_type_node;
894 if (p == NULL || IS_EMPTY_STMT (*p))
896 /* Look through exception handling. */
897 else if (TREE_CODE (*p) == TRY_FINALLY_EXPR
898 || TREE_CODE (*p) == TRY_CATCH_EXPR)
903 /* The C++ frontend already did this for us. */
904 else if (TREE_CODE (*p) == INIT_EXPR)
905 temp = TREE_OPERAND (*p, 0);
906 /* If we're returning a dereference, move the dereference
907 outside the wrapper. */
908 else if (TREE_CODE (*p) == INDIRECT_REF)
910 tree ptr = TREE_OPERAND (*p, 0);
911 temp = create_tmp_var (TREE_TYPE (ptr), "retval");
912 *p = build (MODIFY_EXPR, TREE_TYPE (ptr), temp, ptr);
913 temp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (temp)), temp);
914 /* If this is a BIND_EXPR for a const inline function, it might not
915 have TREE_SIDE_EFFECTS set. That is no longer accurate. */
916 TREE_SIDE_EFFECTS (wrapper) = 1;
921 temp = create_tmp_var (TREE_TYPE (wrapper), "retval");
922 *p = build (MODIFY_EXPR, TREE_TYPE (temp), temp, *p);
923 TREE_SIDE_EFFECTS (wrapper) = 1;
926 TREE_TYPE (wrapper) = void_type_node;
933 /* Prepare calls to builtins to SAVE and RESTORE the stack as well as
934 a temporary through which they communicate. */
937 build_stack_save_restore (tree *save, tree *restore)
939 tree save_call, tmp_var;
942 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_SAVE],
944 tmp_var = create_tmp_var (ptr_type_node, "saved_stack");
946 *save = build (MODIFY_EXPR, ptr_type_node, tmp_var, save_call);
948 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_RESTORE],
949 tree_cons (NULL_TREE, tmp_var, NULL_TREE));
952 /* Gimplify a BIND_EXPR. Just voidify and recurse. */
954 static enum gimplify_status
955 gimplify_bind_expr (tree *expr_p, tree temp, tree *pre_p)
957 tree bind_expr = *expr_p;
958 bool old_save_stack = gimplify_ctxp->save_stack;
961 temp = voidify_wrapper_expr (bind_expr, temp);
963 /* Mark variables seen in this bind expr. */
964 for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t))
965 t->decl.seen_in_bind_expr = 1;
967 gimple_push_bind_expr (bind_expr);
968 gimplify_ctxp->save_stack = false;
970 gimplify_to_stmt_list (&BIND_EXPR_BODY (bind_expr));
972 if (gimplify_ctxp->save_stack)
974 tree stack_save, stack_restore;
976 /* Save stack on entry and restore it on exit. Add a try_finally
977 block to achieve this. Note that mudflap depends on the
978 format of the emitted code: see mx_register_decls(). */
979 build_stack_save_restore (&stack_save, &stack_restore);
981 t = build (TRY_FINALLY_EXPR, void_type_node,
982 BIND_EXPR_BODY (bind_expr), NULL_TREE);
983 append_to_statement_list (stack_restore, &TREE_OPERAND (t, 1));
985 BIND_EXPR_BODY (bind_expr) = NULL_TREE;
986 append_to_statement_list (stack_save, &BIND_EXPR_BODY (bind_expr));
987 append_to_statement_list (t, &BIND_EXPR_BODY (bind_expr));
990 gimplify_ctxp->save_stack = old_save_stack;
991 gimple_pop_bind_expr ();
996 append_to_statement_list (bind_expr, pre_p);
1003 /* Gimplify a RETURN_EXPR. If the expression to be returned is not a
1004 GIMPLE value, it is assigned to a new temporary and the statement is
1005 re-written to return the temporary.
1007 PRE_P points to the list where side effects that must happen before
1008 STMT should be stored. */
1010 static enum gimplify_status
1011 gimplify_return_expr (tree stmt, tree *pre_p)
1013 tree ret_expr = TREE_OPERAND (stmt, 0);
1014 tree result_decl, result;
1016 if (!ret_expr || TREE_CODE (ret_expr) == RESULT_DECL)
1019 if (ret_expr == error_mark_node)
1022 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
1023 result_decl = NULL_TREE;
1026 result_decl = TREE_OPERAND (ret_expr, 0);
1027 #ifdef ENABLE_CHECKING
1028 if ((TREE_CODE (ret_expr) != MODIFY_EXPR
1029 && TREE_CODE (ret_expr) != INIT_EXPR)
1030 || TREE_CODE (result_decl) != RESULT_DECL)
1035 /* If aggregate_value_p is true, then we can return the bare RESULT_DECL.
1036 Recall that aggregate_value_p is FALSE for any aggregate type that is
1037 returned in registers. If we're returning values in registers, then
1038 we don't want to extend the lifetime of the RESULT_DECL, particularly
1039 across another call. In addition, for those aggregates for which
1040 hard_function_value generates a PARALLEL, we'll abort during normal
1041 expansion of structure assignments; there's special code in expand_return
1042 to handle this case that does not exist in expand_expr. */
1044 || aggregate_value_p (result_decl, TREE_TYPE (current_function_decl)))
1045 result = result_decl;
1046 else if (gimplify_ctxp->return_temp)
1047 result = gimplify_ctxp->return_temp;
1050 result = create_tmp_var (TREE_TYPE (result_decl), NULL);
1052 /* ??? With complex control flow (usually involving abnormal edges),
1053 we can wind up warning about an uninitialized value for this. Due
1054 to how this variable is constructed and initialized, this is never
1055 true. Give up and never warn. */
1056 TREE_NO_WARNING (result) = 1;
1058 gimplify_ctxp->return_temp = result;
1061 /* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
1062 Then gimplify the whole thing. */
1063 if (result != result_decl)
1064 TREE_OPERAND (ret_expr, 0) = result;
1065 gimplify_stmt (&TREE_OPERAND (stmt, 0));
1066 append_to_statement_list (TREE_OPERAND (stmt, 0), pre_p);
1068 /* If we didn't use a temporary, then the result is just the result_decl.
1069 Otherwise we need a simple copy. This should already be gimple. */
1070 if (result == result_decl)
1073 ret_expr = build (MODIFY_EXPR, TREE_TYPE (result), result_decl, result);
1074 TREE_OPERAND (stmt, 0) = ret_expr;
1079 /* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body
1080 and replacing the LOOP_EXPR with goto, but if the loop contains an
1081 EXIT_EXPR, we need to append a label for it to jump to. */
1083 static enum gimplify_status
1084 gimplify_loop_expr (tree *expr_p, tree *pre_p)
1086 tree saved_label = gimplify_ctxp->exit_label;
1087 tree start_label = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
1088 tree jump_stmt = build_and_jump (&LABEL_EXPR_LABEL (start_label));
1090 append_to_statement_list (start_label, pre_p);
1092 gimplify_ctxp->exit_label = NULL_TREE;
1094 gimplify_stmt (&LOOP_EXPR_BODY (*expr_p));
1095 append_to_statement_list (LOOP_EXPR_BODY (*expr_p), pre_p);
1097 if (gimplify_ctxp->exit_label)
1099 append_to_statement_list (jump_stmt, pre_p);
1100 *expr_p = build1 (LABEL_EXPR, void_type_node, gimplify_ctxp->exit_label);
1103 *expr_p = jump_stmt;
1105 gimplify_ctxp->exit_label = saved_label;
1110 /* Compare two case labels. Because the front end should already have
1111 made sure that case ranges do not overlap, it is enough to only compare
1112 the CASE_LOW values of each case label. */
1115 compare_case_labels (const void *p1, const void *p2)
1117 tree case1 = *(tree *)p1;
1118 tree case2 = *(tree *)p2;
1120 return tree_int_cst_compare (CASE_LOW (case1), CASE_LOW (case2));
1123 /* Sort the case labels in LABEL_VEC in ascending order. */
1126 sort_case_labels (tree label_vec)
1128 size_t len = TREE_VEC_LENGTH (label_vec);
1129 tree default_case = TREE_VEC_ELT (label_vec, len - 1);
1131 if (CASE_LOW (default_case))
1135 /* The last label in the vector should be the default case
1137 for (i = 0; i < len; ++i)
1139 tree t = TREE_VEC_ELT (label_vec, i);
1143 TREE_VEC_ELT (label_vec, i) = TREE_VEC_ELT (label_vec, len - 1);
1144 TREE_VEC_ELT (label_vec, len - 1) = default_case;
1150 qsort (&TREE_VEC_ELT (label_vec, 0), len - 1, sizeof (tree),
1151 compare_case_labels);
1154 /* Gimplify a SWITCH_EXPR, and collect a TREE_VEC of the labels it can
1157 static enum gimplify_status
1158 gimplify_switch_expr (tree *expr_p, tree *pre_p)
1160 tree switch_expr = *expr_p;
1161 enum gimplify_status ret;
1163 ret = gimplify_expr (&SWITCH_COND (switch_expr), pre_p, NULL,
1164 is_gimple_val, fb_rvalue);
1166 if (SWITCH_BODY (switch_expr))
1168 varray_type labels, saved_labels;
1169 tree label_vec, default_case = NULL_TREE;
1172 /* If someone can be bothered to fill in the labels, they can
1173 be bothered to null out the body too. */
1174 if (SWITCH_LABELS (switch_expr))
1177 saved_labels = gimplify_ctxp->case_labels;
1178 VARRAY_TREE_INIT (gimplify_ctxp->case_labels, 8, "case_labels");
1180 gimplify_to_stmt_list (&SWITCH_BODY (switch_expr));
1182 labels = gimplify_ctxp->case_labels;
1183 gimplify_ctxp->case_labels = saved_labels;
1185 len = VARRAY_ACTIVE_SIZE (labels);
1187 for (i = 0; i < len; ++i)
1189 tree t = VARRAY_TREE (labels, i);
1192 /* The default case must be the last label in the list. */
1194 VARRAY_TREE (labels, i) = VARRAY_TREE (labels, len - 1);
1200 label_vec = make_tree_vec (len + 1);
1201 SWITCH_LABELS (*expr_p) = label_vec;
1202 append_to_statement_list (switch_expr, pre_p);
1206 /* If the switch has no default label, add one, so that we jump
1207 around the switch body. */
1208 default_case = build (CASE_LABEL_EXPR, void_type_node, NULL_TREE,
1209 NULL_TREE, create_artificial_label ());
1210 append_to_statement_list (SWITCH_BODY (switch_expr), pre_p);
1211 *expr_p = build (LABEL_EXPR, void_type_node,
1212 CASE_LABEL (default_case));
1215 *expr_p = SWITCH_BODY (switch_expr);
1217 for (i = 0; i < len; ++i)
1218 TREE_VEC_ELT (label_vec, i) = VARRAY_TREE (labels, i);
1219 TREE_VEC_ELT (label_vec, len) = default_case;
1221 sort_case_labels (label_vec);
1223 SWITCH_BODY (switch_expr) = NULL;
1225 else if (!SWITCH_LABELS (switch_expr))
1231 static enum gimplify_status
1232 gimplify_case_label_expr (tree *expr_p)
1234 tree expr = *expr_p;
1235 if (gimplify_ctxp->case_labels)
1236 VARRAY_PUSH_TREE (gimplify_ctxp->case_labels, expr);
1239 *expr_p = build (LABEL_EXPR, void_type_node, CASE_LABEL (expr));
1243 /* Gimplify a LABELED_BLOCK_EXPR into a LABEL_EXPR following
1244 a (possibly empty) body. */
1246 static enum gimplify_status
1247 gimplify_labeled_block_expr (tree *expr_p)
1249 tree body = LABELED_BLOCK_BODY (*expr_p);
1250 tree label = LABELED_BLOCK_LABEL (*expr_p);
1253 DECL_CONTEXT (label) = current_function_decl;
1254 t = build (LABEL_EXPR, void_type_node, label);
1255 if (body != NULL_TREE)
1256 t = build (COMPOUND_EXPR, void_type_node, body, t);
1262 /* Gimplify a EXIT_BLOCK_EXPR into a GOTO_EXPR. */
1264 static enum gimplify_status
1265 gimplify_exit_block_expr (tree *expr_p)
1267 tree labeled_block = TREE_OPERAND (*expr_p, 0);
1270 /* First operand must be a LABELED_BLOCK_EXPR, which should
1271 already be lowered (or partially lowered) when we get here. */
1272 #if defined ENABLE_CHECKING
1273 if (TREE_CODE (labeled_block) != LABELED_BLOCK_EXPR)
1277 label = LABELED_BLOCK_LABEL (labeled_block);
1278 *expr_p = build1 (GOTO_EXPR, void_type_node, label);
1283 /* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
1287 build_and_jump (tree *label_p)
1289 if (label_p == NULL)
1290 /* If there's nowhere to jump, just fall through. */
1291 return alloc_stmt_list ();
1293 if (*label_p == NULL_TREE)
1295 tree label = create_artificial_label ();
1299 return build1 (GOTO_EXPR, void_type_node, *label_p);
1302 /* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
1303 This also involves building a label to jump to and communicating it to
1304 gimplify_loop_expr through gimplify_ctxp->exit_label. */
1306 static enum gimplify_status
1307 gimplify_exit_expr (tree *expr_p)
1309 tree cond = TREE_OPERAND (*expr_p, 0);
1312 expr = build_and_jump (&gimplify_ctxp->exit_label);
1313 expr = build (COND_EXPR, void_type_node, cond, expr, alloc_stmt_list ());
1319 /* A helper function to be called via walk_tree. Mark all labels under *TP
1320 as being forced. To be called for DECL_INITIAL of static variables. */
1323 force_labels_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1327 if (TREE_CODE (*tp) == LABEL_DECL)
1328 FORCED_LABEL (*tp) = 1;
1333 /* Break out elements of a constructor used as an initializer into separate
1336 Note that we still need to clear any elements that don't have explicit
1337 initializers, so if not all elements are initialized we keep the
1338 original MODIFY_EXPR, we just remove all of the constructor elements. */
1340 static enum gimplify_status
1341 gimplify_init_constructor (tree *expr_p, tree *pre_p,
1342 tree *post_p, bool want_value)
1344 tree object = TREE_OPERAND (*expr_p, 0);
1345 tree ctor = TREE_OPERAND (*expr_p, 1);
1346 tree type = TREE_TYPE (ctor);
1347 enum gimplify_status ret;
1350 if (TREE_CODE (ctor) != CONSTRUCTOR)
1351 return GS_UNHANDLED;
1353 elt_list = CONSTRUCTOR_ELTS (ctor);
1356 switch (TREE_CODE (type))
1360 case QUAL_UNION_TYPE:
1363 HOST_WIDE_INT i, num_elements, num_nonzero_elements;
1364 HOST_WIDE_INT num_nonconstant_elements;
1367 /* Aggregate types must lower constructors to initialization of
1368 individual elements. The exception is that a CONSTRUCTOR node
1369 with no elements indicates zero-initialization of the whole. */
1370 if (elt_list == NULL)
1378 return GS_UNHANDLED;
1381 categorize_ctor_elements (ctor, &num_nonzero_elements,
1382 &num_nonconstant_elements);
1383 num_elements = count_type_elements (TREE_TYPE (ctor));
1385 /* If a const aggregate variable is being initialized, then it
1386 should never be a lose to promote the variable to be static. */
1387 if (num_nonconstant_elements == 0
1388 && TREE_READONLY (object)
1389 && TREE_CODE (object) == VAR_DECL)
1391 DECL_INITIAL (object) = ctor;
1392 TREE_STATIC (object) = 1;
1393 if (!DECL_NAME (object))
1394 DECL_NAME (object) = create_tmp_var_name ("C");
1395 walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL);
1397 /* ??? C++ doesn't automatically append a .<number> to the
1398 assembler name, and even when it does, it looks a FE private
1399 data structures to figure out what that number should be,
1400 which are not set for this variable. I suppose this is
1401 important for local statics for inline functions, which aren't
1402 "local" in the object file sense. So in order to get a unique
1403 TU-local symbol, we must invoke the lhd version now. */
1404 lhd_set_decl_assembler_name (object);
1406 *expr_p = alloc_stmt_list ();
1410 /* If there are "lots" of initialized elements, and all of them
1411 are valid address constants, then the entire initializer can
1412 be dropped to memory, and then memcpy'd out. */
1413 if (num_nonconstant_elements == 0)
1415 HOST_WIDE_INT size = int_size_in_bytes (type);
1418 /* ??? We can still get unbounded array types, at least
1419 from the C++ front end. This seems wrong, but attempt
1420 to work around it for now. */
1423 size = int_size_in_bytes (TREE_TYPE (object));
1425 TREE_TYPE (ctor) = type = TREE_TYPE (object);
1428 /* Find the maximum alignment we can assume for the object. */
1429 /* ??? Make use of DECL_OFFSET_ALIGN. */
1430 if (DECL_P (object))
1431 align = DECL_ALIGN (object);
1433 align = TYPE_ALIGN (type);
1435 if (size > 0 && !can_move_by_pieces (size, align))
1437 tree new = create_tmp_var_raw (type, "C");
1438 gimple_add_tmp_var (new);
1439 TREE_STATIC (new) = 1;
1440 TREE_READONLY (new) = 1;
1441 DECL_INITIAL (new) = ctor;
1442 if (align > DECL_ALIGN (new))
1444 DECL_ALIGN (new) = align;
1445 DECL_USER_ALIGN (new) = 1;
1447 walk_tree (&DECL_INITIAL (new), force_labels_r, NULL, NULL);
1449 TREE_OPERAND (*expr_p, 1) = new;
1454 /* If there are "lots" of initialized elements, even discounting
1455 those that are not address constants (and thus *must* be
1456 computed at runtime), then partition the constructor into
1457 constant and non-constant parts. Block copy the constant
1458 parts in, then generate code for the non-constant parts. */
1459 /* TODO. There's code in cp/typeck.c to do this. */
1461 /* If there are "lots" of zeros, then block clear the object first. */
1463 if (num_elements - num_nonzero_elements > CLEAR_RATIO
1464 && num_nonzero_elements < num_elements/4)
1467 /* ??? This bit ought not be needed. For any element not present
1468 in the initializer, we should simply set them to zero. Except
1469 we'd need to *find* the elements that are not present, and that
1470 requires trickery to avoid quadratic compile-time behavior in
1471 large cases or excessive memory use in small cases. */
1474 HOST_WIDE_INT len = list_length (elt_list);
1475 if (TREE_CODE (type) == ARRAY_TYPE)
1477 tree nelts = array_type_nelts (type);
1478 if (!host_integerp (nelts, 1)
1479 || tree_low_cst (nelts, 1) != len)
1482 else if (len != fields_length (type))
1488 CONSTRUCTOR_ELTS (ctor) = NULL_TREE;
1489 append_to_statement_list (*expr_p, pre_p);
1492 for (i = 0; elt_list; i++, elt_list = TREE_CHAIN (elt_list))
1494 tree purpose, value, cref, init;
1496 purpose = TREE_PURPOSE (elt_list);
1497 value = TREE_VALUE (elt_list);
1499 if (cleared && initializer_zerop (value))
1502 if (TREE_CODE (type) == ARRAY_TYPE)
1504 tree t = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object)));
1506 /* ??? Here's to hoping the front end fills in all of the
1507 indicies, so we don't have to figure out what's missing
1511 /* ??? Need to handle this. */
1512 if (TREE_CODE (purpose) == RANGE_EXPR)
1515 cref = build (ARRAY_REF, t, object, purpose, NULL_TREE, NULL_TREE);
1518 cref = build (COMPONENT_REF, TREE_TYPE (purpose), object,
1519 purpose, NULL_TREE);
1521 init = build (MODIFY_EXPR, TREE_TYPE (purpose), cref, value);
1522 /* Each member initialization is a full-expression. */
1523 gimplify_stmt (&init);
1524 append_to_statement_list (init, pre_p);
1527 *expr_p = alloc_stmt_list ();
1535 /* Extract the real and imaginary parts out of the ctor. */
1539 r = TREE_VALUE (elt_list);
1540 elt_list = TREE_CHAIN (elt_list);
1543 i = TREE_VALUE (elt_list);
1544 if (TREE_CHAIN (elt_list))
1548 if (r == NULL || i == NULL)
1550 tree zero = convert (TREE_TYPE (type), integer_zero_node);
1557 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
1558 represent creation of a complex value. */
1559 if (TREE_CONSTANT (r) && TREE_CONSTANT (i))
1561 ctor = build_complex (type, r, i);
1562 TREE_OPERAND (*expr_p, 1) = ctor;
1566 ctor = build (COMPLEX_EXPR, type, r, i);
1567 TREE_OPERAND (*expr_p, 1) = ctor;
1568 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
1569 is_gimple_rhs, fb_rvalue);
1575 /* Go ahead and simplify constant constructors to VECTOR_CST. */
1576 if (TREE_CONSTANT (ctor))
1577 TREE_OPERAND (*expr_p, 1) = build_vector (type, elt_list);
1580 /* Vector types use CONSTRUCTOR all the way through gimple
1581 compilation as a general initializer. */
1582 for (; elt_list; elt_list = TREE_CHAIN (elt_list))
1584 enum gimplify_status tret;
1585 tret = gimplify_expr (&TREE_VALUE (elt_list), pre_p, post_p,
1586 is_gimple_constructor_elt, fb_rvalue);
1587 if (tret == GS_ERROR)
1594 /* So how did we get a CONSTRUCTOR for a scalar type? */
1598 if (ret == GS_ERROR)
1600 else if (want_value)
1602 append_to_statement_list (*expr_p, pre_p);
1610 /* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is
1611 different from its canonical type, wrap the whole thing inside a
1612 NOP_EXPR and force the type of the COMPONENT_REF to be the canonical
1615 The canonical type of a COMPONENT_REF is the type of the field being
1616 referenced--unless the field is a bit-field which can be read directly
1617 in a smaller mode, in which case the canonical type is the
1618 sign-appropriate type corresponding to that mode. */
1621 canonicalize_component_ref (tree *expr_p)
1623 tree expr = *expr_p;
1626 if (TREE_CODE (expr) != COMPONENT_REF)
1629 if (INTEGRAL_TYPE_P (TREE_TYPE (expr)))
1630 type = TREE_TYPE (get_unwidened (expr, NULL_TREE));
1632 type = TREE_TYPE (TREE_OPERAND (expr, 1));
1634 if (TREE_TYPE (expr) != type)
1636 tree old_type = TREE_TYPE (expr);
1638 /* Set the type of the COMPONENT_REF to the underlying type. */
1639 TREE_TYPE (expr) = type;
1641 /* And wrap the whole thing inside a NOP_EXPR. */
1642 expr = build1 (NOP_EXPR, old_type, expr);
1648 /* If a NOP conversion is changing a pointer to array of foo to a pointer
1649 to foo, embed that change in the ADDR_EXPR by converting
1654 where L is the lower bound. Only do this for constant lower bound since
1655 we have no place to put any statements made during gimplification of
1659 canonicalize_addr_expr (tree *expr_p)
1661 tree expr = *expr_p;
1662 tree ctype = TREE_TYPE (expr);
1663 tree addr_expr = TREE_OPERAND (expr, 0);
1664 tree atype = TREE_TYPE (addr_expr);
1665 tree dctype, datype, ddatype, otype, obj_expr;
1667 /* Both cast and addr_expr types should be pointers. */
1668 if (!POINTER_TYPE_P (ctype) || !POINTER_TYPE_P (atype))
1671 /* The addr_expr type should be a pointer to an array. */
1672 datype = TREE_TYPE (atype);
1673 if (TREE_CODE (datype) != ARRAY_TYPE)
1676 /* Both cast and addr_expr types should address the same object type. */
1677 dctype = TREE_TYPE (ctype);
1678 ddatype = TREE_TYPE (datype);
1679 if (!lang_hooks.types_compatible_p (ddatype, dctype))
1682 /* The addr_expr and the object type should match. */
1683 obj_expr = TREE_OPERAND (addr_expr, 0);
1684 otype = TREE_TYPE (obj_expr);
1685 if (!lang_hooks.types_compatible_p (otype, datype))
1688 /* The lower bound and element sizes must be constant. */
1689 if (TREE_CODE (TYPE_SIZE_UNIT (dctype)) != INTEGER_CST
1690 || !TYPE_DOMAIN (datype) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype))
1691 || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype))) != INTEGER_CST)
1694 /* All checks succeeded. Build a new node to merge the cast. */
1695 *expr_p = build4 (ARRAY_REF, dctype, obj_expr,
1696 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1697 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1698 size_binop (EXACT_DIV_EXPR, TYPE_SIZE_UNIT (dctype),
1699 size_int (TYPE_ALIGN (dctype)
1701 *expr_p = build1 (ADDR_EXPR, ctype, *expr_p);
1704 /* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
1705 underneath as appropriate. */
1707 static enum gimplify_status
1708 gimplify_conversion (tree *expr_p)
1710 /* Strip away as many useless type conversions as possible
1712 STRIP_USELESS_TYPE_CONVERSION (*expr_p);
1714 /* If we still have a conversion at the toplevel, then strip
1715 away all but the outermost conversion. */
1716 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1718 STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0));
1720 /* And remove the outermost conversion if it's useless. */
1721 if (tree_ssa_useless_type_conversion (*expr_p))
1722 *expr_p = TREE_OPERAND (*expr_p, 0);
1725 /* If we still have a conversion at the toplevel,
1726 then canonicalize some constructs. */
1727 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1729 tree sub = TREE_OPERAND (*expr_p, 0);
1731 /* If a NOP conversion is changing the type of a COMPONENT_REF
1732 expression, then canonicalize its type now in order to expose more
1733 redundant conversions. */
1734 if (TREE_CODE (sub) == COMPONENT_REF)
1735 canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0));
1737 /* If a NOP conversion is changing a pointer to array of foo
1738 to a pointer to foo, embed that change in the ADDR_EXPR. */
1739 else if (TREE_CODE (sub) == ADDR_EXPR)
1740 canonicalize_addr_expr (expr_p);
1746 /* Reduce MIN/MAX_EXPR to a COND_EXPR for further gimplification. */
1748 static enum gimplify_status
1749 gimplify_minimax_expr (tree *expr_p, tree *pre_p, tree *post_p)
1751 tree op1 = TREE_OPERAND (*expr_p, 0);
1752 tree op2 = TREE_OPERAND (*expr_p, 1);
1753 enum tree_code code;
1754 enum gimplify_status r0, r1;
1756 if (TREE_CODE (*expr_p) == MIN_EXPR)
1761 r0 = gimplify_expr (&op1, pre_p, post_p, is_gimple_val, fb_rvalue);
1762 r1 = gimplify_expr (&op2, pre_p, post_p, is_gimple_val, fb_rvalue);
1764 *expr_p = build (COND_EXPR, TREE_TYPE (*expr_p),
1765 build (code, boolean_type_node, op1, op2),
1768 if (r0 == GS_ERROR || r1 == GS_ERROR)
1774 /* Subroutine of gimplify_compound_lval.
1775 Converts an ARRAY_REF to the equivalent *(&array + offset) form. */
1777 static enum gimplify_status
1778 gimplify_array_ref_to_plus (tree *expr_p, tree *pre_p, tree *post_p)
1780 tree array = TREE_OPERAND (*expr_p, 0);
1781 tree arrtype = TREE_TYPE (array);
1782 tree elttype = TREE_TYPE (arrtype);
1783 tree size = array_ref_element_size (*expr_p);
1784 tree ptrtype = build_pointer_type (elttype);
1785 enum tree_code add_code = PLUS_EXPR;
1786 tree idx = TREE_OPERAND (*expr_p, 1);
1787 tree minidx = unshare_expr (array_ref_low_bound (*expr_p));
1788 tree offset, addr, result;
1789 enum gimplify_status ret;
1791 /* If the array domain does not start at zero, apply the offset. */
1792 if (!integer_zerop (minidx))
1794 idx = convert (TREE_TYPE (minidx), idx);
1795 idx = fold (build (MINUS_EXPR, TREE_TYPE (minidx), idx, minidx));
1798 /* If the index is negative -- a technically invalid situation now
1799 that we've biased the index back to zero -- then casting it to
1800 unsigned has ill effects. In particular, -1*4U/4U != -1.
1801 Represent this as a subtraction of a positive rather than addition
1802 of a negative. This will prevent any conversion back to ARRAY_REF
1803 from getting the wrong results from the division. */
1804 if (TREE_CODE (idx) == INTEGER_CST && tree_int_cst_sgn (idx) < 0)
1806 idx = fold (build1 (NEGATE_EXPR, TREE_TYPE (idx), idx));
1807 add_code = MINUS_EXPR;
1810 /* Pointer arithmetic must be done in sizetype. */
1811 idx = fold_convert (sizetype, idx);
1813 /* Convert the index to a byte offset. */
1814 offset = size_binop (MULT_EXPR, size, idx);
1816 ret = gimplify_expr (&array, pre_p, post_p, is_gimple_min_lval, fb_lvalue);
1817 if (ret == GS_ERROR)
1820 addr = build_fold_addr_expr_with_type (array, ptrtype);
1821 result = fold (build (add_code, ptrtype, addr, offset));
1822 *expr_p = build1 (INDIRECT_REF, elttype, result);
1827 /* Build an expression for the address of T. Folds away INDIRECT_REF to
1828 avoid confusing the gimplify process. */
1831 build_addr_expr_with_type (tree t, tree ptrtype)
1833 if (TREE_CODE (t) == INDIRECT_REF)
1835 t = TREE_OPERAND (t, 0);
1836 if (TREE_TYPE (t) != ptrtype)
1837 t = build1 (NOP_EXPR, ptrtype, t);
1843 if (TREE_CODE (base) == REALPART_EXPR
1844 || TREE_CODE (base) == IMAGPART_EXPR)
1845 base = TREE_OPERAND (base, 0);
1847 while (handled_component_p (base))
1848 base = TREE_OPERAND (base, 0);
1851 TREE_ADDRESSABLE (base) = 1;
1853 t = build1 (ADDR_EXPR, ptrtype, t);
1860 build_addr_expr (tree t)
1862 return build_addr_expr_with_type (t, build_pointer_type (TREE_TYPE (t)));
1865 /* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
1866 node pointed by EXPR_P.
1869 : min_lval '[' val ']'
1871 | compound_lval '[' val ']'
1872 | compound_lval '.' ID
1874 This is not part of the original SIMPLE definition, which separates
1875 array and member references, but it seems reasonable to handle them
1876 together. Also, this way we don't run into problems with union
1877 aliasing; gcc requires that for accesses through a union to alias, the
1878 union reference must be explicit, which was not always the case when we
1879 were splitting up array and member refs.
1881 PRE_P points to the list where side effects that must happen before
1882 *EXPR_P should be stored.
1884 POST_P points to the list where side effects that must happen after
1885 *EXPR_P should be stored. */
1887 static enum gimplify_status
1888 gimplify_compound_lval (tree *expr_p, tree *pre_p,
1889 tree *post_p, bool want_lvalue)
1893 enum gimplify_status ret = GS_OK, tret;
1895 #if defined ENABLE_CHECKING
1896 if (TREE_CODE (*expr_p) != ARRAY_REF
1897 && TREE_CODE (*expr_p) != ARRAY_RANGE_REF
1898 && TREE_CODE (*expr_p) != COMPONENT_REF
1899 && TREE_CODE (*expr_p) != BIT_FIELD_REF
1900 && TREE_CODE (*expr_p) != REALPART_EXPR
1901 && TREE_CODE (*expr_p) != IMAGPART_EXPR)
1905 /* Create a stack of the subexpressions so later we can walk them in
1906 order from inner to outer. */
1907 VARRAY_TREE_INIT (stack, 10, "stack");
1909 /* We can either handle one REALPART_EXPR or IMAGEPART_EXPR or
1910 nest of handled components. */
1911 if (TREE_CODE (*expr_p) == REALPART_EXPR
1912 || TREE_CODE (*expr_p) == IMAGPART_EXPR)
1913 p = &TREE_OPERAND (*expr_p, 0);
1915 for (p = expr_p; handled_component_p (*p); p = &TREE_OPERAND (*p, 0))
1916 VARRAY_PUSH_TREE (stack, *p);
1918 /* Now STACK is a stack of pointers to all the refs we've walked through
1919 and P points to the innermost expression.
1921 Process each of the outer nodes from left to right, then gimplify the
1922 base. We need to do it in this order so that PLACEHOLDER_EXPRs
1924 for (; VARRAY_ACTIVE_SIZE (stack) > 0; )
1926 tree t = VARRAY_TOP_TREE (stack);
1928 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1930 /* Gimplify the dimension.
1931 Temporary fix for gcc.c-torture/execute/20040313-1.c.
1932 Gimplify non-constant array indices into a temporary
1934 FIXME - The real fix is to gimplify post-modify
1935 expressions into a minimal gimple lvalue. However, that
1936 exposes bugs in alias analysis. The alias analyzer does
1937 not handle &PTR->FIELD very well. Will fix after the
1938 branch is merged into mainline (dnovillo 2004-05-03). */
1939 if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
1941 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1942 is_gimple_tmp_var, fb_rvalue);
1943 ret = MIN (ret, tret);
1946 /* Gimplify the low bound and element type size and put them into
1947 the ARRAY_REF. If these values are set, they have already been
1949 if (!TREE_OPERAND (t, 2))
1951 TREE_OPERAND (t, 2) = unshare_expr (array_ref_low_bound (t));
1952 if (!is_gimple_min_invariant (TREE_OPERAND (t, 2)))
1954 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1955 is_gimple_tmp_var, fb_rvalue);
1956 ret = MIN (ret, tret);
1960 if (!TREE_OPERAND (t, 3))
1962 tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
1963 tree elmt_size = unshare_expr (array_ref_element_size (t));
1964 tree factor = size_int (TYPE_ALIGN (elmt_type) / BITS_PER_UNIT);
1966 /* Divide the element size by the alignment of the element
1968 elmt_size = size_binop (EXACT_DIV_EXPR, elmt_size, factor);
1970 TREE_OPERAND (t, 3) = elmt_size;
1971 if (!is_gimple_min_invariant (TREE_OPERAND (t, 3)))
1973 tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p,
1974 is_gimple_tmp_var, fb_rvalue);
1975 ret = MIN (ret, tret);
1979 else if (TREE_CODE (t) == COMPONENT_REF)
1981 /* Set the field offset into T and gimplify it. */
1982 if (!TREE_OPERAND (t, 2))
1984 tree offset = unshare_expr (component_ref_field_offset (t));
1985 tree field = TREE_OPERAND (t, 1);
1987 = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
1989 /* Divide the offset by its alignment. */
1990 offset = size_binop (EXACT_DIV_EXPR, offset, factor);
1992 TREE_OPERAND (t, 2) = offset;
1993 if (!is_gimple_min_invariant (TREE_OPERAND (t, 2)))
1995 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1996 is_gimple_tmp_var, fb_rvalue);
1997 ret = MIN (ret, tret);
2001 else if (TREE_CODE (t) == BIT_FIELD_REF)
2003 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
2004 is_gimple_val, fb_rvalue);
2005 ret = MIN (ret, tret);
2006 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
2007 is_gimple_val, fb_rvalue);
2008 ret = MIN (ret, tret);
2011 recalculate_side_effects (t);
2015 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval,
2016 want_lvalue ? fb_lvalue : fb_rvalue);
2017 ret = MIN (ret, tret);
2019 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
2020 if (!want_lvalue && TREE_CODE (*expr_p) == COMPONENT_REF)
2022 canonicalize_component_ref (expr_p);
2023 ret = MIN (ret, GS_OK);
2029 /* Gimplify the self modifying expression pointed by EXPR_P (++, --, +=, -=).
2031 PRE_P points to the list where side effects that must happen before
2032 *EXPR_P should be stored.
2034 POST_P points to the list where side effects that must happen after
2035 *EXPR_P should be stored.
2037 WANT_VALUE is nonzero iff we want to use the value of this expression
2038 in another expression. */
2040 static enum gimplify_status
2041 gimplify_self_mod_expr (tree *expr_p, tree *pre_p, tree *post_p,
2044 enum tree_code code;
2045 tree lhs, lvalue, rhs, t1;
2047 enum tree_code arith_code;
2048 enum gimplify_status ret;
2050 code = TREE_CODE (*expr_p);
2052 #if defined ENABLE_CHECKING
2053 if (code != POSTINCREMENT_EXPR
2054 && code != POSTDECREMENT_EXPR
2055 && code != PREINCREMENT_EXPR
2056 && code != PREDECREMENT_EXPR)
2060 /* Prefix or postfix? */
2061 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
2062 /* Faster to treat as prefix if result is not used. */
2063 postfix = want_value;
2067 /* Add or subtract? */
2068 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2069 arith_code = PLUS_EXPR;
2071 arith_code = MINUS_EXPR;
2073 /* Gimplify the LHS into a GIMPLE lvalue. */
2074 lvalue = TREE_OPERAND (*expr_p, 0);
2075 ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
2076 if (ret == GS_ERROR)
2079 /* Extract the operands to the arithmetic operation. */
2081 rhs = TREE_OPERAND (*expr_p, 1);
2083 /* For postfix operator, we evaluate the LHS to an rvalue and then use
2084 that as the result value and in the postqueue operation. */
2087 ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
2088 if (ret == GS_ERROR)
2092 t1 = build (arith_code, TREE_TYPE (*expr_p), lhs, rhs);
2093 t1 = build (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
2097 gimplify_stmt (&t1);
2098 append_to_statement_list (t1, post_p);
2109 /* Gimplify the CALL_EXPR node pointed by EXPR_P.
2112 : ID '(' arglist ')'
2118 PRE_P points to the list where side effects that must happen before
2119 *EXPR_P should be stored. */
2121 static enum gimplify_status
2122 gimplify_call_expr (tree *expr_p, tree *pre_p, bool (*gimple_test_f) (tree))
2126 enum gimplify_status ret;
2128 #if defined ENABLE_CHECKING
2129 if (TREE_CODE (*expr_p) != CALL_EXPR)
2133 /* For reliable diagnostics during inlining, it is necessary that
2134 every call_expr be annotated with file and line. */
2135 if (!EXPR_LOCUS (*expr_p))
2136 annotate_with_locus (*expr_p, input_location);
2138 /* This may be a call to a builtin function.
2140 Builtin function calls may be transformed into different
2141 (and more efficient) builtin function calls under certain
2142 circumstances. Unfortunately, gimplification can muck things
2143 up enough that the builtin expanders are not aware that certain
2144 transformations are still valid.
2146 So we attempt transformation/gimplification of the call before
2147 we gimplify the CALL_EXPR. At this time we do not manage to
2148 transform all calls in the same manner as the expanders do, but
2149 we do transform most of them. */
2150 decl = get_callee_fndecl (*expr_p);
2151 if (decl && DECL_BUILT_IN (decl))
2155 /* If it is allocation of stack, record the need to restore the memory
2156 when the enclosing bind_expr is exited. */
2157 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_STACK_ALLOC)
2158 gimplify_ctxp->save_stack = true;
2160 /* If it is restore of the stack, reset it, since it means we are
2161 regimplifying the bind_expr. Note that we use the fact that
2162 for try_finally_expr, try part is processed first. */
2163 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_STACK_RESTORE)
2164 gimplify_ctxp->save_stack = false;
2166 new = simplify_builtin (*expr_p, gimple_test_f == is_gimple_stmt);
2168 if (new && new != *expr_p)
2170 /* There was a transformation of this call which computes the
2171 same value, but in a more efficient way. Return and try
2178 /* There is a sequence point before the call, so any side effects in
2179 the calling expression must occur before the actual call. Force
2180 gimplify_expr to use an internal post queue. */
2181 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, NULL,
2182 is_gimple_call_addr, fb_rvalue);
2184 if (PUSH_ARGS_REVERSED)
2185 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
2186 for (arglist = TREE_OPERAND (*expr_p, 1); arglist;
2187 arglist = TREE_CHAIN (arglist))
2189 enum gimplify_status t;
2191 /* There is a sequence point before a function call. Side effects in
2192 the argument list must occur before the actual call. So, when
2193 gimplifying arguments, force gimplify_expr to use an internal
2194 post queue which is then appended to the end of PRE_P. */
2195 t = gimplify_expr (&TREE_VALUE (arglist), pre_p, NULL, is_gimple_val,
2201 if (PUSH_ARGS_REVERSED)
2202 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
2204 /* Try this again in case gimplification exposed something. */
2205 if (ret != GS_ERROR && decl && DECL_BUILT_IN (decl))
2207 tree new = simplify_builtin (*expr_p, gimple_test_f == is_gimple_stmt);
2209 if (new && new != *expr_p)
2211 /* There was a transformation of this call which computes the
2212 same value, but in a more efficient way. Return and try
2219 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
2220 decl. This allows us to eliminate redundant or useless
2221 calls to "const" functions. */
2222 if (TREE_CODE (*expr_p) == CALL_EXPR
2223 && (call_expr_flags (*expr_p) & (ECF_CONST | ECF_PURE)))
2224 TREE_SIDE_EFFECTS (*expr_p) = 0;
2229 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
2230 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
2232 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
2233 condition is true or false, respectively. If null, we should generate
2234 our own to skip over the evaluation of this specific expression.
2236 This function is the tree equivalent of do_jump.
2238 shortcut_cond_r should only be called by shortcut_cond_expr. */
2241 shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p)
2243 tree local_label = NULL_TREE;
2244 tree t, expr = NULL;
2246 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
2247 retain the shortcut semantics. Just insert the gotos here;
2248 shortcut_cond_expr will append the real blocks later. */
2249 if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2251 /* Turn if (a && b) into
2253 if (a); else goto no;
2254 if (b) goto yes; else goto no;
2257 if (false_label_p == NULL)
2258 false_label_p = &local_label;
2260 t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p);
2261 append_to_statement_list (t, &expr);
2263 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2265 append_to_statement_list (t, &expr);
2267 else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2269 /* Turn if (a || b) into
2272 if (b) goto yes; else goto no;
2275 if (true_label_p == NULL)
2276 true_label_p = &local_label;
2278 t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL);
2279 append_to_statement_list (t, &expr);
2281 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2283 append_to_statement_list (t, &expr);
2285 else if (TREE_CODE (pred) == COND_EXPR)
2287 /* As long as we're messing with gotos, turn if (a ? b : c) into
2289 if (b) goto yes; else goto no;
2291 if (c) goto yes; else goto no; */
2292 expr = build (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
2293 shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2295 shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
2300 expr = build (COND_EXPR, void_type_node, pred,
2301 build_and_jump (true_label_p),
2302 build_and_jump (false_label_p));
2307 t = build1 (LABEL_EXPR, void_type_node, local_label);
2308 append_to_statement_list (t, &expr);
2315 shortcut_cond_expr (tree expr)
2317 tree pred = TREE_OPERAND (expr, 0);
2318 tree then_ = TREE_OPERAND (expr, 1);
2319 tree else_ = TREE_OPERAND (expr, 2);
2320 tree true_label, false_label, end_label, t;
2322 tree *false_label_p;
2323 bool emit_end, emit_false;
2325 /* First do simple transformations. */
2326 if (!TREE_SIDE_EFFECTS (else_))
2328 /* If there is no 'else', turn (a && b) into if (a) if (b). */
2329 while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2331 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2332 then_ = shortcut_cond_expr (expr);
2333 pred = TREE_OPERAND (pred, 0);
2334 expr = build (COND_EXPR, void_type_node, pred, then_,
2335 alloc_stmt_list ());
2338 if (!TREE_SIDE_EFFECTS (then_))
2340 /* If there is no 'then', turn
2343 if (a); else if (b); else d. */
2344 while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2346 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2347 else_ = shortcut_cond_expr (expr);
2348 pred = TREE_OPERAND (pred, 0);
2349 expr = build (COND_EXPR, void_type_node, pred,
2350 alloc_stmt_list (), else_);
2354 /* If we're done, great. */
2355 if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
2356 && TREE_CODE (pred) != TRUTH_ORIF_EXPR)
2359 /* Otherwise we need to mess with gotos. Change
2362 if (a); else goto no;
2365 and recursively gimplify the condition. */
2367 true_label = false_label = end_label = NULL_TREE;
2369 /* If our arms just jump somewhere, hijack those labels so we don't
2370 generate jumps to jumps. */
2372 if (TREE_CODE (then_) == GOTO_EXPR
2373 && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
2375 true_label = GOTO_DESTINATION (then_);
2376 then_ = alloc_stmt_list ();
2379 if (TREE_CODE (else_) == GOTO_EXPR
2380 && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
2382 false_label = GOTO_DESTINATION (else_);
2383 else_ = alloc_stmt_list ();
2386 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2388 true_label_p = &true_label;
2390 true_label_p = NULL;
2392 /* The 'else' branch also needs a label if it contains interesting code. */
2393 if (false_label || TREE_SIDE_EFFECTS (else_))
2394 false_label_p = &false_label;
2396 false_label_p = NULL;
2398 /* If there was nothing else in our arms, just forward the label(s). */
2399 if (!TREE_SIDE_EFFECTS (then_) && !TREE_SIDE_EFFECTS (else_))
2400 return shortcut_cond_r (pred, true_label_p, false_label_p);
2402 /* If our last subexpression already has a terminal label, reuse it. */
2403 if (TREE_SIDE_EFFECTS (else_))
2404 expr = expr_last (else_);
2406 expr = expr_last (then_);
2407 if (TREE_CODE (expr) == LABEL_EXPR)
2408 end_label = LABEL_EXPR_LABEL (expr);
2410 /* If we don't care about jumping to the 'else' branch, jump to the end
2411 if the condition is false. */
2413 false_label_p = &end_label;
2415 /* We only want to emit these labels if we aren't hijacking them. */
2416 emit_end = (end_label == NULL_TREE);
2417 emit_false = (false_label == NULL_TREE);
2419 pred = shortcut_cond_r (pred, true_label_p, false_label_p);
2422 append_to_statement_list (pred, &expr);
2424 append_to_statement_list (then_, &expr);
2425 if (TREE_SIDE_EFFECTS (else_))
2427 t = build_and_jump (&end_label);
2428 append_to_statement_list (t, &expr);
2431 t = build1 (LABEL_EXPR, void_type_node, false_label);
2432 append_to_statement_list (t, &expr);
2434 append_to_statement_list (else_, &expr);
2436 if (emit_end && end_label)
2438 t = build1 (LABEL_EXPR, void_type_node, end_label);
2439 append_to_statement_list (t, &expr);
2445 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2448 gimple_boolify (tree expr)
2450 tree type = TREE_TYPE (expr);
2452 if (TREE_CODE (type) == BOOLEAN_TYPE)
2455 /* If this is the predicate of a COND_EXPR, it might not even be a
2457 expr = lang_hooks.truthvalue_conversion (expr);
2459 switch (TREE_CODE (expr))
2461 case TRUTH_AND_EXPR:
2463 case TRUTH_XOR_EXPR:
2464 case TRUTH_ANDIF_EXPR:
2465 case TRUTH_ORIF_EXPR:
2466 /* Also boolify the arguments of truth exprs. */
2467 TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
2470 case TRUTH_NOT_EXPR:
2471 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2474 case EQ_EXPR: case NE_EXPR:
2475 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2476 /* These expressions always produce boolean results. */
2477 TREE_TYPE (expr) = boolean_type_node;
2481 /* Other expressions that get here must have boolean values, but
2482 might need to be converted to the appropriate mode. */
2483 return convert (boolean_type_node, expr);
2487 /* Convert the conditional expression pointed by EXPR_P '(p) ? a : b;'
2496 The second form is used when *EXPR_P is of type void.
2498 TARGET is the tree for T1 above.
2500 PRE_P points to the list where side effects that must happen before
2501 *EXPR_P should be stored. */
2503 static enum gimplify_status
2504 gimplify_cond_expr (tree *expr_p, tree *pre_p, tree target)
2506 tree expr = *expr_p;
2508 enum gimplify_status ret;
2510 /* If this COND_EXPR has a value, copy the values into a temporary within
2512 if (! VOID_TYPE_P (TREE_TYPE (expr)))
2521 tmp = create_tmp_var (TREE_TYPE (expr), "iftmp");
2525 /* Build the then clause, 't1 = a;'. But don't build an assignment
2526 if this branch is void; in C++ it can be, if it's a throw. */
2527 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2528 TREE_OPERAND (expr, 1)
2529 = build (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 1));
2531 /* Build the else clause, 't1 = b;'. */
2532 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2533 TREE_OPERAND (expr, 2)
2534 = build (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 2));
2536 TREE_TYPE (expr) = void_type_node;
2537 recalculate_side_effects (expr);
2539 /* Move the COND_EXPR to the prequeue and use the temp in its place. */
2540 gimplify_stmt (&expr);
2541 append_to_statement_list (expr, pre_p);
2547 /* Make sure the condition has BOOLEAN_TYPE. */
2548 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2550 /* Break apart && and || conditions. */
2551 if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
2552 || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
2554 expr = shortcut_cond_expr (expr);
2556 if (expr != *expr_p)
2560 /* We can't rely on gimplify_expr to re-gimplify the expanded
2561 form properly, as cleanups might cause the target labels to be
2562 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2563 set up a conditional context. */
2564 gimple_push_condition ();
2565 gimplify_stmt (expr_p);
2566 gimple_pop_condition (pre_p);
2572 /* Now do the normal gimplification. */
2573 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2574 is_gimple_condexpr, fb_rvalue);
2576 gimple_push_condition ();
2578 gimplify_to_stmt_list (&TREE_OPERAND (expr, 1));
2579 gimplify_to_stmt_list (&TREE_OPERAND (expr, 2));
2580 recalculate_side_effects (expr);
2582 gimple_pop_condition (pre_p);
2584 if (ret == GS_ERROR)
2586 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2588 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 2)))
2589 /* Rewrite "if (a); else b" to "if (!a) b" */
2591 TREE_OPERAND (expr, 0) = invert_truthvalue (TREE_OPERAND (expr, 0));
2592 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2593 is_gimple_condexpr, fb_rvalue);
2595 tmp = TREE_OPERAND (expr, 1);
2596 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 2);
2597 TREE_OPERAND (expr, 2) = tmp;
2600 /* Both arms are empty; replace the COND_EXPR with its predicate. */
2601 expr = TREE_OPERAND (expr, 0);
2607 /* Gimplify the MODIFY_EXPR node pointed by EXPR_P.
2613 PRE_P points to the list where side effects that must happen before
2614 *EXPR_P should be stored.
2616 POST_P points to the list where side effects that must happen after
2617 *EXPR_P should be stored.
2619 WANT_VALUE is nonzero iff we want to use the value of this expression
2620 in another expression. */
2622 static enum gimplify_status
2623 gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value)
2625 tree *from_p = &TREE_OPERAND (*expr_p, 1);
2626 tree *to_p = &TREE_OPERAND (*expr_p, 0);
2627 enum gimplify_status ret = GS_UNHANDLED;
2629 #if defined ENABLE_CHECKING
2630 if (TREE_CODE (*expr_p) != MODIFY_EXPR && TREE_CODE (*expr_p) != INIT_EXPR)
2634 /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer useful. */
2635 if (TREE_CODE (*expr_p) == INIT_EXPR)
2636 TREE_SET_CODE (*expr_p, MODIFY_EXPR);
2638 /* See if any simplifications can be done based on what the RHS is. */
2639 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2641 if (ret != GS_UNHANDLED)
2644 /* If the value being copied is of variable width, expose the length
2645 if the copy by converting the whole thing to a memcpy. Note that
2646 we need to do this before gimplifying any of the operands
2647 so that we can resolve any PLACEHOLDER_EXPRs in the size. */
2648 if (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (*to_p))) != INTEGER_CST)
2652 t = TYPE_SIZE_UNIT (TREE_TYPE (*to_p));
2653 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, *to_p);
2654 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, *from_p);
2655 t = unshare_expr (t);
2656 args = tree_cons (NULL, t, NULL);
2657 t = build_fold_addr_expr (*from_p);
2658 args = tree_cons (NULL, t, args);
2659 dest = build_fold_addr_expr (*to_p);
2660 args = tree_cons (NULL, dest, args);
2661 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
2662 t = build_function_call_expr (t, args);
2665 t = build1 (NOP_EXPR, TREE_TYPE (dest), t);
2666 t = build1 (INDIRECT_REF, TREE_TYPE (*to_p), t);
2672 ret = gimplify_expr (to_p, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
2673 if (ret == GS_ERROR)
2676 ret = gimplify_expr (from_p, pre_p, post_p, is_gimple_rhs, fb_rvalue);
2677 if (ret == GS_ERROR)
2680 /* Now see if the above changed *from_p to something we handle specially. */
2681 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2683 if (ret != GS_UNHANDLED)
2686 /* If the destination is already simple, nothing else needed. */
2687 if (is_gimple_tmp_var (*to_p))
2691 /* If the RHS of the MODIFY_EXPR may throw or make a nonlocal goto and
2692 the LHS is a user variable, then we need to introduce a temporary.
2693 ie temp = RHS; LHS = temp.
2695 This way the optimizers can determine that the user variable is
2696 only modified if evaluation of the RHS does not throw.
2698 FIXME this should be handled by the is_gimple_rhs predicate. */
2700 if (aggregate_value_p (TREE_TYPE (*from_p), NULL_TREE))
2701 /* Don't force a temp of a large aggregate type; the copy could be
2702 arbitrarily expensive. Instead we will generate a V_MAY_DEF for
2704 else if (TREE_CODE (*from_p) == CALL_EXPR
2705 || (flag_non_call_exceptions && tree_could_trap_p (*from_p))
2706 /* If we're dealing with a renamable type, either source or dest
2707 must be a renamed variable. */
2708 || (is_gimple_reg_type (TREE_TYPE (*from_p))
2709 && !is_gimple_reg (*to_p)))
2710 gimplify_expr (from_p, pre_p, post_p, is_gimple_val, fb_rvalue);
2712 ret = want_value ? GS_OK : GS_ALL_DONE;
2717 append_to_statement_list (*expr_p, pre_p);
2724 /* Subroutine of above to do simplications of MODIFY_EXPRs based on
2725 the code of the RHS. We loop for as long as we can do something. */
2727 static enum gimplify_status
2728 gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p,
2729 tree *post_p, bool want_value)
2731 enum gimplify_status ret = GS_OK;
2733 while (ret != GS_UNHANDLED)
2734 switch (TREE_CODE (*from_p))
2738 /* If we are initializing something from a TARGET_EXPR, strip the
2739 TARGET_EXPR and initialize it directly, if possible. This can't
2740 be done if the initializer is void, since that implies that the
2741 temporary is set in some non-trivial way.
2743 ??? What about code that pulls out the temp and uses it
2744 elsewhere? I think that such code never uses the TARGET_EXPR as
2745 an initializer. If I'm wrong, we'll abort because the temp won't
2746 have any RTL. In that case, I guess we'll need to replace
2747 references somehow. */
2748 tree init = TARGET_EXPR_INITIAL (*from_p);
2750 if (!VOID_TYPE_P (TREE_TYPE (init)))
2761 /* Remove any COMPOUND_EXPR in the RHS so the following cases will be
2763 gimplify_compound_expr (from_p, pre_p, true);
2768 /* If we're initializing from a CONSTRUCTOR, break this into
2769 individual MODIFY_EXPRs. */
2770 return gimplify_init_constructor (expr_p, pre_p, post_p, want_value);
2773 /* If we're assigning from a ?: expression with ADDRESSABLE type, push
2774 the assignment down into the branches, since we can't generate a
2775 temporary of such a type. */
2776 if (TREE_ADDRESSABLE (TREE_TYPE (*from_p)))
2779 return gimplify_cond_expr (expr_p, pre_p, *to_p);
2793 /* Gimplify a comparison between two variable-sized objects. Do this
2794 with a call to BUILT_IN_MEMCMP. */
2796 static enum gimplify_status
2797 gimplify_variable_sized_compare (tree *expr_p)
2799 tree op0 = TREE_OPERAND (*expr_p, 0);
2800 tree op1 = TREE_OPERAND (*expr_p, 1);
2803 t = TYPE_SIZE_UNIT (TREE_TYPE (op0));
2804 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, op0);
2805 t = unshare_expr (t);
2806 args = tree_cons (NULL, t, NULL);
2807 t = build_addr_expr (op1);
2808 args = tree_cons (NULL, t, args);
2809 dest = build_addr_expr (op0);
2810 args = tree_cons (NULL, dest, args);
2811 t = implicit_built_in_decls[BUILT_IN_MEMCMP];
2812 t = build_function_call_expr (t, args);
2814 = build (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), t, integer_zero_node);
2819 /* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P
2820 points to the expression to gimplify.
2822 Expressions of the form 'a && b' are gimplified to:
2824 a && b ? true : false
2826 gimplify_cond_expr will do the rest.
2828 PRE_P points to the list where side effects that must happen before
2829 *EXPR_P should be stored. */
2831 static enum gimplify_status
2832 gimplify_boolean_expr (tree *expr_p)
2834 /* Preserve the original type of the expression. */
2835 tree type = TREE_TYPE (*expr_p);
2837 *expr_p = build (COND_EXPR, type, *expr_p,
2838 convert (type, boolean_true_node),
2839 convert (type, boolean_false_node));
2844 /* Gimplifies an expression sequence. This function gimplifies each
2845 expression and re-writes the original expression with the last
2846 expression of the sequence in GIMPLE form.
2848 PRE_P points to the list where the side effects for all the
2849 expressions in the sequence will be emitted.
2851 WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */
2852 /* ??? Should rearrange to share the pre-queue with all the indirect
2853 invocations of gimplify_expr. Would probably save on creations
2854 of statement_list nodes. */
2856 static enum gimplify_status
2857 gimplify_compound_expr (tree *expr_p, tree *pre_p, bool want_value)
2863 tree *sub_p = &TREE_OPERAND (t, 0);
2865 if (TREE_CODE (*sub_p) == COMPOUND_EXPR)
2866 gimplify_compound_expr (sub_p, pre_p, false);
2868 gimplify_stmt (sub_p);
2869 append_to_statement_list (*sub_p, pre_p);
2871 t = TREE_OPERAND (t, 1);
2873 while (TREE_CODE (t) == COMPOUND_EXPR);
2880 gimplify_stmt (expr_p);
2885 /* Gimplifies a statement list. These may be created either by an
2886 enlightened front-end, or by shortcut_cond_expr. */
2888 static enum gimplify_status
2889 gimplify_statement_list (tree *expr_p)
2891 tree_stmt_iterator i = tsi_start (*expr_p);
2893 while (!tsi_end_p (i))
2897 gimplify_stmt (tsi_stmt_ptr (i));
2900 if (TREE_CODE (t) == STATEMENT_LIST)
2902 tsi_link_before (&i, t, TSI_SAME_STMT);
2912 /* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to
2913 gimplify. After gimplification, EXPR_P will point to a new temporary
2914 that holds the original value of the SAVE_EXPR node.
2916 PRE_P points to the list where side effects that must happen before
2917 *EXPR_P should be stored. */
2919 static enum gimplify_status
2920 gimplify_save_expr (tree *expr_p, tree *pre_p, tree *post_p)
2922 enum gimplify_status ret = GS_ALL_DONE;
2925 #if defined ENABLE_CHECKING
2926 if (TREE_CODE (*expr_p) != SAVE_EXPR)
2930 val = TREE_OPERAND (*expr_p, 0);
2932 /* If the operand is already a GIMPLE temporary, just re-write the
2934 if (is_gimple_tmp_var (val))
2936 /* The operand may be a void-valued expression such as SAVE_EXPRs
2937 generated by the Java frontend for class initialization. It is
2938 being executed only for its side-effects. */
2939 else if (TREE_TYPE (val) == void_type_node)
2941 tree body = TREE_OPERAND (*expr_p, 0);
2942 ret = gimplify_expr (& body, pre_p, post_p, is_gimple_stmt, fb_none);
2943 append_to_statement_list (body, pre_p);
2944 *expr_p = alloc_stmt_list ();
2947 *expr_p = TREE_OPERAND (*expr_p, 0)
2948 = get_initialized_tmp_var (val, pre_p, post_p);
2953 /* Re-write the ADDR_EXPR node pointed by EXPR_P
2960 PRE_P points to the list where side effects that must happen before
2961 *EXPR_P should be stored.
2963 POST_P points to the list where side effects that must happen after
2964 *EXPR_P should be stored. */
2966 static enum gimplify_status
2967 gimplify_addr_expr (tree *expr_p, tree *pre_p, tree *post_p)
2969 tree expr = *expr_p;
2970 tree op0 = TREE_OPERAND (expr, 0);
2971 enum gimplify_status ret;
2973 switch (TREE_CODE (op0))
2976 /* Check if we are dealing with an expression of the form '&*ptr'.
2977 While the front end folds away '&*ptr' into 'ptr', these
2978 expressions may be generated internally by the compiler (e.g.,
2979 builtins like __builtin_va_end). */
2980 *expr_p = TREE_OPERAND (op0, 0);
2985 /* Fold &a[6] to (&a + 6). */
2986 ret = gimplify_array_ref_to_plus (&TREE_OPERAND (expr, 0),
2989 /* This added an INDIRECT_REF. Fold it away. */
2990 *expr_p = TREE_OPERAND (TREE_OPERAND (expr, 0), 0);
2993 case VIEW_CONVERT_EXPR:
2994 /* Take the address of our operand and then convert it to the type of
2996 *expr_p = fold_convert (TREE_TYPE (expr),
2997 build_addr_expr (TREE_OPERAND (op0, 0)));
3002 /* We use fb_either here because the C frontend sometimes takes
3003 the address of a call that returns a struct. */
3004 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, post_p,
3005 is_gimple_addr_expr_arg, fb_either);
3006 if (ret != GS_ERROR)
3008 /* At this point, the argument of the ADDR_EXPR should be
3009 sufficiently simple that there are never side effects. */
3010 /* ??? Could split out the decision code from build1 to verify. */
3011 TREE_SIDE_EFFECTS (expr) = 0;
3013 /* Make sure TREE_INVARIANT/TREE_CONSTANT is set properly. */
3014 recompute_tree_invarant_for_addr_expr (expr);
3016 /* Mark the RHS addressable. */
3017 lang_hooks.mark_addressable (TREE_OPERAND (expr, 0));
3022 /* If the operand is gimplified into a _DECL, mark the address expression
3023 as TREE_INVARIANT. */
3024 if (DECL_P (TREE_OPERAND (expr, 0)))
3025 TREE_INVARIANT (expr) = 1;
3030 /* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple
3031 value; output operands should be a gimple lvalue. */
3033 static enum gimplify_status
3034 gimplify_asm_expr (tree *expr_p, tree *pre_p, tree *post_p)
3036 tree expr = *expr_p;
3037 int noutputs = list_length (ASM_OUTPUTS (expr));
3038 const char **oconstraints
3039 = (const char **) alloca ((noutputs) * sizeof (const char *));
3042 const char *constraint;
3043 bool allows_mem, allows_reg, is_inout;
3044 enum gimplify_status ret, tret;
3047 = resolve_asm_operand_names (ASM_STRING (expr), ASM_OUTPUTS (expr),
3051 for (i = 0, link = ASM_OUTPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3053 oconstraints[i] = constraint
3054 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3056 parse_output_constraint (&constraint, i, 0, 0,
3057 &allows_mem, &allows_reg, &is_inout);
3059 if (!allows_reg && allows_mem)
3060 lang_hooks.mark_addressable (TREE_VALUE (link));
3062 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3063 is_inout ? is_gimple_min_lval : is_gimple_lvalue,
3064 fb_lvalue | fb_mayfail);
3065 if (tret == GS_ERROR)
3067 error ("invalid lvalue in asm output %d", i);
3073 /* An input/output operand. To give the optimizers more
3074 flexibility, split it into separate input and output
3078 size_t constraint_len = strlen (constraint);
3080 /* Turn the in/out constraint into an output constraint. */
3081 char *p = xstrdup (constraint);
3083 TREE_VALUE (TREE_PURPOSE (link)) = build_string (constraint_len, p);
3086 /* And add a matching input constraint. */
3089 sprintf (buf, "%d", i);
3090 input = build_string (strlen (buf), buf);
3093 input = build_string (constraint_len - 1, constraint + 1);
3094 input = build_tree_list (build_tree_list (NULL_TREE, input),
3095 unshare_expr (TREE_VALUE (link)));
3096 ASM_INPUTS (expr) = chainon (ASM_INPUTS (expr), input);
3100 for (link = ASM_INPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3103 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3104 parse_input_constraint (&constraint, 0, 0, noutputs, 0,
3105 oconstraints, &allows_mem, &allows_reg);
3107 /* If the operand is a memory input, it should be an lvalue. */
3108 if (!allows_reg && allows_mem)
3110 lang_hooks.mark_addressable (TREE_VALUE (link));
3111 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3112 is_gimple_lvalue, fb_lvalue | fb_mayfail);
3113 if (tret == GS_ERROR)
3115 error ("memory input %d is not directly addressable", i);
3121 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3122 is_gimple_val, fb_rvalue);
3123 if (tret == GS_ERROR)
3131 /* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding
3132 WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
3133 gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
3134 return to this function.
3136 FIXME should we complexify the prequeue handling instead? Or use flags
3137 for all the cleanups and let the optimizer tighten them up? The current
3138 code seems pretty fragile; it will break on a cleanup within any
3139 non-conditional nesting. But any such nesting would be broken, anyway;
3140 we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
3141 and continues out of it. We can do that at the RTL level, though, so
3142 having an optimizer to tighten up try/finally regions would be a Good
3145 static enum gimplify_status
3146 gimplify_cleanup_point_expr (tree *expr_p, tree *pre_p)
3148 tree_stmt_iterator iter;
3151 tree temp = voidify_wrapper_expr (*expr_p, NULL);
3153 /* We only care about the number of conditions between the innermost
3154 CLEANUP_POINT_EXPR and the cleanup. So save and reset the count. */
3155 int old_conds = gimplify_ctxp->conditions;
3156 gimplify_ctxp->conditions = 0;
3158 body = TREE_OPERAND (*expr_p, 0);
3159 gimplify_to_stmt_list (&body);
3161 gimplify_ctxp->conditions = old_conds;
3163 for (iter = tsi_start (body); !tsi_end_p (iter); )
3165 tree *wce_p = tsi_stmt_ptr (iter);
3168 if (TREE_CODE (wce) == WITH_CLEANUP_EXPR)
3170 if (tsi_one_before_end_p (iter))
3172 tsi_link_before (&iter, TREE_OPERAND (wce, 1), TSI_SAME_STMT);
3180 sl = tsi_split_statement_list_after (&iter);
3181 tfe = build (TRY_FINALLY_EXPR, void_type_node, sl, NULL_TREE);
3182 append_to_statement_list (TREE_OPERAND (wce, 1),
3183 &TREE_OPERAND (tfe, 1));
3185 iter = tsi_start (sl);
3195 append_to_statement_list (body, pre_p);
3205 /* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP
3206 is the cleanup action required. */
3209 gimple_push_cleanup (tree var, tree cleanup, tree *pre_p)
3213 /* Errors can result in improperly nested cleanups. Which results in
3214 confusion when trying to resolve the WITH_CLEANUP_EXPR. */
3215 if (errorcount || sorrycount)
3218 if (gimple_conditional_context ())
3220 /* If we're in a conditional context, this is more complex. We only
3221 want to run the cleanup if we actually ran the initialization that
3222 necessitates it, but we want to run it after the end of the
3223 conditional context. So we wrap the try/finally around the
3224 condition and use a flag to determine whether or not to actually
3225 run the destructor. Thus
3229 becomes (approximately)
3233 if (test) { A::A(temp); flag = 1; val = f(temp); }
3236 if (flag) A::~A(temp);
3241 tree flag = create_tmp_var (boolean_type_node, "cleanup");
3242 tree ffalse = build (MODIFY_EXPR, void_type_node, flag,
3243 boolean_false_node);
3244 tree ftrue = build (MODIFY_EXPR, void_type_node, flag,
3246 cleanup = build (COND_EXPR, void_type_node, flag, cleanup,
3247 alloc_stmt_list ());
3248 wce = build (WITH_CLEANUP_EXPR, void_type_node, NULL_TREE,
3249 cleanup, NULL_TREE);
3250 append_to_statement_list (ffalse, &gimplify_ctxp->conditional_cleanups);
3251 append_to_statement_list (wce, &gimplify_ctxp->conditional_cleanups);
3252 append_to_statement_list (ftrue, pre_p);
3254 /* Because of this manipulation, and the EH edges that jump
3255 threading cannot redirect, the temporary (VAR) will appear
3256 to be used uninitialized. Don't warn. */
3257 TREE_NO_WARNING (var) = 1;
3261 wce = build (WITH_CLEANUP_EXPR, void_type_node, NULL_TREE,
3262 cleanup, NULL_TREE);
3263 append_to_statement_list (wce, pre_p);
3266 gimplify_stmt (&TREE_OPERAND (wce, 1));
3269 /* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */
3271 static enum gimplify_status
3272 gimplify_target_expr (tree *expr_p, tree *pre_p, tree *post_p)
3274 tree targ = *expr_p;
3275 tree temp = TARGET_EXPR_SLOT (targ);
3276 tree init = TARGET_EXPR_INITIAL (targ);
3277 enum gimplify_status ret;
3281 /* TARGET_EXPR temps aren't part of the enclosing block, so add it
3282 to the temps list. */
3283 gimple_add_tmp_var (temp);
3285 /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
3286 expression is supposed to initialize the slot. */
3287 if (VOID_TYPE_P (TREE_TYPE (init)))
3288 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, fb_none);
3291 /* Special handling for BIND_EXPR can result in fewer temps. */
3293 if (TREE_CODE (init) == BIND_EXPR)
3294 gimplify_bind_expr (&init, temp, pre_p);
3297 init = build (MODIFY_EXPR, void_type_node, temp, init);
3298 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt,
3302 if (ret == GS_ERROR)
3304 append_to_statement_list (init, pre_p);
3306 /* If needed, push the cleanup for the temp. */
3307 if (TARGET_EXPR_CLEANUP (targ))
3309 gimplify_stmt (&TARGET_EXPR_CLEANUP (targ));
3310 gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ), pre_p);
3313 /* Only expand this once. */
3314 TREE_OPERAND (targ, 3) = init;
3315 TARGET_EXPR_INITIAL (targ) = NULL_TREE;
3317 else if (!temp->decl.seen_in_bind_expr)
3318 /* We should have expanded this before. */
3325 /* Gimplification of expression trees. */
3327 /* Gimplify an expression which appears at statement context; usually, this
3328 means replacing it with a suitably gimple STATEMENT_LIST. */
3331 gimplify_stmt (tree *stmt_p)
3333 gimplify_expr (stmt_p, NULL, NULL, is_gimple_stmt, fb_none);
3335 *stmt_p = alloc_stmt_list ();
3338 /* Similarly, but force the result to be a STATEMENT_LIST. */
3341 gimplify_to_stmt_list (tree *stmt_p)
3343 gimplify_stmt (stmt_p);
3344 if (TREE_CODE (*stmt_p) != STATEMENT_LIST)
3347 *stmt_p = alloc_stmt_list ();
3348 append_to_statement_list (t, stmt_p);
3353 /* Gimplifies the expression tree pointed by EXPR_P. Return 0 if
3354 gimplification failed.
3356 PRE_P points to the list where side effects that must happen before
3357 EXPR should be stored.
3359 POST_P points to the list where side effects that must happen after
3360 EXPR should be stored, or NULL if there is no suitable list. In
3361 that case, we copy the result to a temporary, emit the
3362 post-effects, and then return the temporary.
3364 GIMPLE_TEST_F points to a function that takes a tree T and
3365 returns nonzero if T is in the GIMPLE form requested by the
3366 caller. The GIMPLE predicates are in tree-gimple.c.
3368 This test is used twice. Before gimplification, the test is
3369 invoked to determine whether *EXPR_P is already gimple enough. If
3370 that fails, *EXPR_P is gimplified according to its code and
3371 GIMPLE_TEST_F is called again. If the test still fails, then a new
3372 temporary variable is created and assigned the value of the
3373 gimplified expression.
3375 FALLBACK tells the function what sort of a temporary we want. If the 1
3376 bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK.
3377 If both are set, either is OK, but an lvalue is preferable.
3379 The return value is either GS_ERROR or GS_ALL_DONE, since this function
3380 iterates until solution. */
3382 enum gimplify_status
3383 gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
3384 bool (* gimple_test_f) (tree), fallback_t fallback)
3387 tree internal_pre = NULL_TREE;
3388 tree internal_post = NULL_TREE;
3390 int is_statement = (pre_p == NULL);
3392 location_t saved_location;
3393 enum gimplify_status ret;
3395 save_expr = *expr_p;
3396 if (save_expr == NULL_TREE)
3399 /* We used to check the predicate here and return immediately if it
3400 succeeds. This is wrong; the design is for gimplification to be
3401 idempotent, and for the predicates to only test for valid forms, not
3402 whether they are fully simplified. */
3404 /* Set up our internal queues if needed. */
3406 pre_p = &internal_pre;
3408 post_p = &internal_post;
3410 saved_location = input_location;
3411 if (save_expr == error_mark_node)
3414 locus = EXPR_LOCUS (save_expr);
3416 input_location = *locus;
3418 /* Loop over the specific gimplifiers until the toplevel node
3419 remains the same. */
3422 /* Strip any uselessness. */
3423 STRIP_MAIN_TYPE_NOPS (*expr_p);
3425 /* Remember the expr. */
3426 save_expr = *expr_p;
3428 /* Die, die, die, my darling. */
3429 if (save_expr == error_mark_node
3430 || TREE_TYPE (save_expr) == error_mark_node)
3436 /* Do any language-specific gimplification. */
3437 ret = lang_hooks.gimplify_expr (expr_p, pre_p, post_p);
3440 if (*expr_p == NULL_TREE)
3442 if (*expr_p != save_expr)
3445 else if (ret != GS_UNHANDLED)
3449 switch (TREE_CODE (*expr_p))
3451 /* First deal with the special cases. */
3453 case POSTINCREMENT_EXPR:
3454 case POSTDECREMENT_EXPR:
3455 case PREINCREMENT_EXPR:
3456 case PREDECREMENT_EXPR:
3457 ret = gimplify_self_mod_expr (expr_p, pre_p, post_p,
3458 fallback != fb_none);
3462 case ARRAY_RANGE_REF:
3466 ret = gimplify_compound_lval (expr_p, pre_p, post_p,
3467 fallback & fb_lvalue);
3471 ret = gimplify_cond_expr (expr_p, pre_p, NULL_TREE);
3475 ret = gimplify_call_expr (expr_p, pre_p, gimple_test_f);
3482 ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none);
3487 ret = gimplify_modify_expr (expr_p, pre_p, post_p,
3488 fallback != fb_none);
3491 case TRUTH_ANDIF_EXPR:
3492 case TRUTH_ORIF_EXPR:
3493 ret = gimplify_boolean_expr (expr_p);
3496 case TRUTH_NOT_EXPR:
3497 TREE_OPERAND (*expr_p, 0)
3498 = gimple_boolify (TREE_OPERAND (*expr_p, 0));
3499 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3500 is_gimple_val, fb_rvalue);
3501 recalculate_side_effects (*expr_p);
3505 ret = gimplify_addr_expr (expr_p, pre_p, post_p);
3509 ret = gimplify_va_arg_expr (expr_p, pre_p, post_p);
3512 case VIEW_CONVERT_EXPR:
3513 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
3514 || fallback == fb_none)
3516 /* Just strip a conversion to void (or in void context) and
3518 *expr_p = TREE_OPERAND (*expr_p, 0);
3522 /* If both types are BLKmode or if one type is of variable size,
3523 convert this into a pointer punning operation. This avoids
3524 copies of large data or making a variable-size temporary. */
3525 if ((TYPE_MODE (TREE_TYPE (*expr_p)) == BLKmode
3526 && TYPE_MODE (TREE_TYPE (TREE_OPERAND (*expr_p, 0))) == BLKmode)
3527 || !TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (*expr_p)))
3528 || !TREE_CONSTANT (TYPE_SIZE (TREE_TYPE
3529 (TREE_OPERAND (*expr_p,0)))))
3531 tree restype = TREE_TYPE (*expr_p);
3532 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (*expr_p),
3533 fold_convert (build_pointer_type (restype),
3535 (TREE_OPERAND (*expr_p, 0))));
3542 if (IS_EMPTY_STMT (*expr_p))
3548 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
3549 || fallback == fb_none)
3551 /* Just strip a conversion to void (or in void context) and
3553 *expr_p = TREE_OPERAND (*expr_p, 0);
3557 ret = gimplify_conversion (expr_p);
3558 if (ret == GS_ERROR)
3560 if (*expr_p != save_expr)
3564 case FIX_TRUNC_EXPR:
3566 case FIX_FLOOR_EXPR:
3567 case FIX_ROUND_EXPR:
3569 /* unary_expr: ... | '(' cast ')' val | ... */
3570 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3571 is_gimple_val, fb_rvalue);
3572 recalculate_side_effects (*expr_p);
3576 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3577 is_gimple_reg, fb_rvalue);
3578 recalculate_side_effects (*expr_p);
3581 /* Constants need not be gimplified. */
3591 *expr_p = DECL_INITIAL (*expr_p);
3595 /* FIXME make this a decl. */
3600 ret = gimplify_bind_expr (expr_p, NULL, pre_p);
3604 ret = gimplify_loop_expr (expr_p, pre_p);
3608 ret = gimplify_switch_expr (expr_p, pre_p);
3611 case LABELED_BLOCK_EXPR:
3612 ret = gimplify_labeled_block_expr (expr_p);
3615 case EXIT_BLOCK_EXPR:
3616 ret = gimplify_exit_block_expr (expr_p);
3620 ret = gimplify_exit_expr (expr_p);
3624 /* If the target is not LABEL, then it is a computed jump
3625 and the target needs to be gimplified. */
3626 if (TREE_CODE (GOTO_DESTINATION (*expr_p)) != LABEL_DECL)
3627 ret = gimplify_expr (&GOTO_DESTINATION (*expr_p), pre_p,
3628 NULL, is_gimple_val, fb_rvalue);
3633 #ifdef ENABLE_CHECKING
3634 if (decl_function_context (LABEL_EXPR_LABEL (*expr_p)) != current_function_decl)
3639 case CASE_LABEL_EXPR:
3640 ret = gimplify_case_label_expr (expr_p);
3644 ret = gimplify_return_expr (*expr_p, pre_p);
3648 /* Don't reduce this in place; let gimplify_init_constructor work
3653 /* The following are special cases that are not handled by the
3654 original GIMPLE grammar. */
3656 /* SAVE_EXPR nodes are converted into a GIMPLE identifier and
3659 ret = gimplify_save_expr (expr_p, pre_p, post_p);
3664 enum gimplify_status r0, r1, r2;
3666 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3667 is_gimple_min_lval, fb_either);
3668 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3669 is_gimple_val, fb_rvalue);
3670 r2 = gimplify_expr (&TREE_OPERAND (*expr_p, 2), pre_p, post_p,
3671 is_gimple_val, fb_rvalue);
3672 recalculate_side_effects (*expr_p);
3674 ret = MIN (r0, MIN (r1, r2));
3678 case NON_LVALUE_EXPR:
3679 /* This should have been stripped above. */
3684 ret = gimplify_asm_expr (expr_p, pre_p, post_p);
3687 case TRY_FINALLY_EXPR:
3688 case TRY_CATCH_EXPR:
3689 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 0));
3690 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 1));
3694 case CLEANUP_POINT_EXPR:
3695 ret = gimplify_cleanup_point_expr (expr_p, pre_p);
3699 ret = gimplify_target_expr (expr_p, pre_p, post_p);
3703 gimplify_to_stmt_list (&CATCH_BODY (*expr_p));
3707 case EH_FILTER_EXPR:
3708 gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p));
3714 enum gimplify_status r0, r1;
3715 r0 = gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p), pre_p, post_p,
3716 is_gimple_val, fb_rvalue);
3717 r1 = gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p), pre_p, post_p,
3718 is_gimple_val, fb_rvalue);
3725 ret = gimplify_minimax_expr (expr_p, pre_p, post_p);
3729 /* We get here when taking the address of a label. We mark
3730 the label as "forced"; meaning it can never be removed and
3731 it is a potential target for any computed goto. */
3732 FORCED_LABEL (*expr_p) = 1;
3736 case STATEMENT_LIST:
3737 ret = gimplify_statement_list (expr_p);
3741 /* ??? If this is a local variable, and it has not been seen in any
3742 outer BIND_EXPR, then it's probably the result of a duplicate
3743 declaration, for which we've already issued an error. It would
3744 be really nice if the front end wouldn't leak these at all.
3745 Currently the only known culprit is C++ destructors, as seen
3746 in g++.old-deja/g++.jason/binding.C. */
3748 if (!TREE_STATIC (tmp) && !DECL_EXTERNAL (tmp)
3749 && decl_function_context (tmp) == current_function_decl
3750 && !tmp->decl.seen_in_bind_expr)
3752 #ifdef ENABLE_CHECKING
3753 if (!errorcount && !sorrycount)
3763 /* If this is a comparison of objects of aggregate type, handle
3764 it specially (by converting to a call to memcmp). It would be
3765 nice to only have to do this for variable-sized objects, but
3766 then we'd have to allow the same nest of reference nodes we
3767 allow for MODIFY_EXPR and that's too complex. */
3768 if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3769 && (AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 1)))))
3770 ret = gimplify_variable_sized_compare (expr_p);
3772 /* If *EXPR_P does not need to be special-cased, handle it
3773 according to its class. */
3774 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '1')
3775 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3776 post_p, is_gimple_val, fb_rvalue);
3777 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '2'
3778 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3779 || TREE_CODE (*expr_p) == TRUTH_AND_EXPR
3780 || TREE_CODE (*expr_p) == TRUTH_OR_EXPR
3781 || TREE_CODE (*expr_p) == TRUTH_XOR_EXPR)
3783 enum gimplify_status r0, r1;
3785 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3786 post_p, is_gimple_val, fb_rvalue);
3787 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p,
3788 post_p, is_gimple_val, fb_rvalue);
3792 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'd'
3793 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'c')
3799 /* Fail if we don't know how to handle this tree code. */
3802 recalculate_side_effects (*expr_p);
3806 /* If we replaced *expr_p, gimplify again. */
3807 if (ret == GS_OK && (*expr_p == NULL || *expr_p == save_expr))
3810 while (ret == GS_OK);
3812 /* If we encountered an error_mark somewhere nested inside, either
3813 stub out the statement or propagate the error back out. */
3814 if (ret == GS_ERROR)
3817 *expr_p = alloc_stmt_list ();
3821 #ifdef ENABLE_CHECKING
3822 /* This was only valid as a return value from the langhook, which
3823 we handled. Make sure it doesn't escape from any other context. */
3824 if (ret == GS_UNHANDLED)
3829 *expr_p = alloc_stmt_list ();
3830 if (fallback == fb_none && !is_gimple_stmt (*expr_p))
3832 /* We aren't looking for a value, and we don't have a valid
3833 statement. If it doesn't have side-effects, throw it away. */
3834 if (!TREE_SIDE_EFFECTS (*expr_p))
3835 *expr_p = alloc_stmt_list ();
3836 else if (!TREE_THIS_VOLATILE (*expr_p))
3838 /* This is probably a _REF that contains something nested that
3839 has side effects. Recurse through the operands to find it. */
3840 enum tree_code code = TREE_CODE (*expr_p);
3842 if (code == COMPONENT_REF
3843 || code == REALPART_EXPR || code == IMAGPART_EXPR)
3844 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3845 gimple_test_f, fallback);
3846 else if (code == ARRAY_REF || code == ARRAY_RANGE_REF)
3848 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3849 gimple_test_f, fallback);
3850 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3851 gimple_test_f, fallback);
3854 /* Anything else with side-effects
3855 must be converted to a valid statement before we get here. */
3858 *expr_p = alloc_stmt_list ();
3860 else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p)))
3862 /* Historically, the compiler has treated a bare
3863 reference to a volatile lvalue as forcing a load. */
3864 tree tmp = create_tmp_var (TREE_TYPE (*expr_p), "vol");
3865 *expr_p = build (MODIFY_EXPR, TREE_TYPE (tmp), tmp, *expr_p);
3868 /* We can't do anything useful with a volatile reference to
3869 incomplete type, so just throw it away. */
3870 *expr_p = alloc_stmt_list ();
3873 /* If we are gimplifying at the statement level, we're done. Tack
3874 everything together and replace the original statement with the
3876 if (fallback == fb_none || is_statement)
3878 if (internal_pre || internal_post)
3880 append_to_statement_list (*expr_p, &internal_pre);
3881 append_to_statement_list (internal_post, &internal_pre);
3882 annotate_all_with_locus (&internal_pre, input_location);
3883 *expr_p = internal_pre;
3885 else if (TREE_CODE (*expr_p) == STATEMENT_LIST)
3886 annotate_all_with_locus (expr_p, input_location);
3888 annotate_one_with_locus (*expr_p, input_location);
3892 /* Otherwise we're gimplifying a subexpression, so the resulting value is
3895 /* If it's sufficiently simple already, we're done. Unless we are
3896 handling some post-effects internally; if that's the case, we need to
3897 copy into a temp before adding the post-effects to the tree. */
3898 if (!internal_post && (*gimple_test_f) (*expr_p))
3901 /* Otherwise, we need to create a new temporary for the gimplified
3904 /* We can't return an lvalue if we have an internal postqueue. The
3905 object the lvalue refers to would (probably) be modified by the
3906 postqueue; we need to copy the value out first, which means an
3908 if ((fallback & fb_lvalue) && !internal_post
3909 && is_gimple_addr_expr_arg (*expr_p))
3911 /* An lvalue will do. Take the address of the expression, store it
3912 in a temporary, and replace the expression with an INDIRECT_REF of
3914 tmp = build_fold_addr_expr (*expr_p);
3915 gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue);
3916 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp);
3918 else if ((fallback & fb_rvalue) && is_gimple_rhs (*expr_p))
3920 #if defined ENABLE_CHECKING
3921 if (VOID_TYPE_P (TREE_TYPE (*expr_p)))
3925 /* An rvalue will do. Assign the gimplified expression into a new
3926 temporary TMP and replace the original expression with TMP. */
3928 if (internal_post || (fallback & fb_lvalue))
3929 /* The postqueue might change the value of the expression between
3930 the initialization and use of the temporary, so we can't use a
3931 formal temp. FIXME do we care? */
3932 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
3934 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
3936 else if (fallback & fb_mayfail)
3938 /* If this is an asm statement, and the user asked for the impossible,
3939 don't abort. Fail and let gimplify_asm_expr issue an error. */
3945 fprintf (stderr, "gimplification failed:\n");
3946 print_generic_expr (stderr, *expr_p, 0);
3947 debug_tree (*expr_p);
3951 #if defined ENABLE_CHECKING
3952 /* Make sure the temporary matches our predicate. */
3953 if (!(*gimple_test_f) (*expr_p))
3959 annotate_all_with_locus (&internal_post, input_location);
3960 append_to_statement_list (internal_post, pre_p);
3964 input_location = saved_location;
3968 /* Look through TYPE for variable-sized objects and gimplify each such
3969 size that we find. Return a STATEMENT_LIST containing the result. */
3972 gimplify_type_sizes (tree type)
3974 tree stmts = NULL_TREE;
3977 switch (TREE_CODE (type))
3980 return alloc_stmt_list ();
3987 gimplify_one_sizepos (&TYPE_MIN_VALUE (type), &stmts);
3988 gimplify_one_sizepos (&TYPE_MAX_VALUE (type), &stmts);
3992 /* These anonymous types don't have declarations, so handle them here. */
3993 append_to_statement_list (gimplify_type_sizes (TYPE_DOMAIN (type)),
3999 case QUAL_UNION_TYPE:
4000 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4001 if (TREE_CODE (field) == FIELD_DECL)
4002 gimplify_one_sizepos (&DECL_FIELD_OFFSET (field), &stmts);
4009 gimplify_one_sizepos (&TYPE_SIZE (type), &stmts);
4010 gimplify_one_sizepos (&TYPE_SIZE_UNIT (type), &stmts);
4013 stmts = alloc_stmt_list ();
4018 /* Subroutine of the above to gimplify one size or position, *EXPR_P.
4019 We add any required statements to STMT_P. */
4022 gimplify_one_sizepos (tree *expr_p, tree *stmt_p)
4024 tree pre = NULL_TREE, post = NULL_TREE;
4026 /* We don't do anything if the value isn't there, is constant, or contains
4027 A PLACEHOLDER_EXPR. */
4028 if (*expr_p == NULL_TREE || TREE_CONSTANT (*expr_p)
4029 || CONTAINS_PLACEHOLDER_P (*expr_p))
4032 gimplify_expr (expr_p, &pre, &post, is_gimple_val, fb_rvalue);
4035 append_to_statement_list (pre, stmt_p);
4037 append_to_statement_list (post, stmt_p);
4040 #ifdef ENABLE_CHECKING
4041 /* Compare types A and B for a "close enough" match. */
4044 cpt_same_type (tree a, tree b)
4046 if (lang_hooks.types_compatible_p (a, b))
4049 /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't
4050 link them together. This routine is intended to catch type errors
4051 that will affect the optimizers, and the optimizers don't add new
4052 dereferences of function pointers, so ignore it. */
4053 if ((TREE_CODE (a) == FUNCTION_TYPE || TREE_CODE (a) == METHOD_TYPE)
4054 && (TREE_CODE (b) == FUNCTION_TYPE || TREE_CODE (b) == METHOD_TYPE))
4057 /* ??? The C FE pushes type qualifiers after the fact into the type of
4058 the element from the type of the array. See build_unary_op's handling
4059 of ADDR_EXPR. This seems wrong -- if we were going to do this, we
4060 should have done it when creating the variable in the first place.
4061 Alternately, why aren't the two array types made variants? */
4062 if (TREE_CODE (a) == ARRAY_TYPE && TREE_CODE (b) == ARRAY_TYPE)
4063 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4065 /* And because of those, we have to recurse down through pointers. */
4066 if (POINTER_TYPE_P (a) && POINTER_TYPE_P (b))
4067 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4072 /* Check for some cases of the front end missing cast expressions.
4073 The type of a dereference should correspond to the pointer type;
4074 similarly the type of an address should match its object. */
4077 check_pointer_types_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
4078 void *data ATTRIBUTE_UNUSED)
4081 tree ptype, otype, dtype;
4083 switch (TREE_CODE (t))
4087 otype = TREE_TYPE (t);
4088 ptype = TREE_TYPE (TREE_OPERAND (t, 0));
4089 dtype = TREE_TYPE (ptype);
4090 if (!cpt_same_type (otype, dtype))
4095 ptype = TREE_TYPE (t);
4096 otype = TREE_TYPE (TREE_OPERAND (t, 0));
4097 dtype = TREE_TYPE (ptype);
4098 if (!cpt_same_type (otype, dtype))
4100 /* &array is allowed to produce a pointer to the element, rather than
4101 a pointer to the array type. We must allow this in order to
4102 properly represent assigning the address of an array in C into
4103 pointer to the element type. */
4104 if (TREE_CODE (otype) == ARRAY_TYPE
4105 && POINTER_TYPE_P (ptype)
4106 && cpt_same_type (TREE_TYPE (otype), dtype))
4121 /* Gimplify the body of statements pointed by BODY_P. FNDECL is the
4122 function decl containing BODY. */
4125 gimplify_body (tree *body_p, tree fndecl)
4127 location_t saved_location = input_location;
4130 timevar_push (TV_TREE_GIMPLIFY);
4131 push_gimplify_context ();
4133 /* Unshare most shared trees in the body and in that of any nested functions.
4134 It would seem we don't have to do this for nested functions because
4135 they are supposed to be output and then the outer function gimplified
4136 first, but the g++ front end doesn't always do it that way. */
4137 unshare_body (body_p, fndecl);
4138 unvisit_body (body_p, fndecl);
4140 /* Make sure input_location isn't set to something wierd. */
4141 input_location = DECL_SOURCE_LOCATION (fndecl);
4143 /* Gimplify the function's body. */
4144 gimplify_stmt (body_p);
4147 /* Unshare again, in case gimplification was sloppy. */
4148 unshare_all_trees (body);
4150 if (TREE_CODE (body) == STATEMENT_LIST)
4152 tree t = expr_only (*body_p);
4157 /* If there isn't an outer BIND_EXPR, add one. */
4158 if (TREE_CODE (body) != BIND_EXPR)
4160 tree b = build (BIND_EXPR, void_type_node, NULL_TREE,
4161 NULL_TREE, NULL_TREE);
4162 TREE_SIDE_EFFECTS (b) = 1;
4163 append_to_statement_list_force (body, &BIND_EXPR_BODY (b));
4168 pop_gimplify_context (body);
4170 #ifdef ENABLE_CHECKING
4171 walk_tree (body_p, check_pointer_types_r, NULL, NULL);
4174 timevar_pop (TV_TREE_GIMPLIFY);
4175 input_location = saved_location;
4178 /* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL
4179 node for the function we want to gimplify. */
4182 gimplify_function_tree (tree fndecl)
4186 oldfn = current_function_decl;
4187 current_function_decl = fndecl;
4189 gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl);
4191 /* If we're instrumenting function entry/exit, then prepend the call to
4192 the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
4193 catch the exit hook. */
4194 /* ??? Add some way to ignore exceptions for this TFE. */
4195 if (flag_instrument_function_entry_exit
4196 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl))
4200 tf = build (TRY_FINALLY_EXPR, void_type_node, NULL, NULL);
4201 TREE_SIDE_EFFECTS (tf) = 1;
4202 x = DECL_SAVED_TREE (fndecl);
4203 append_to_statement_list (x, &TREE_OPERAND (tf, 0));
4204 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_EXIT];
4205 x = build_function_call_expr (x, NULL);
4206 append_to_statement_list (x, &TREE_OPERAND (tf, 1));
4208 bind = build (BIND_EXPR, void_type_node, NULL, NULL, NULL);
4209 TREE_SIDE_EFFECTS (bind) = 1;
4210 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_ENTER];
4211 x = build_function_call_expr (x, NULL);
4212 append_to_statement_list (x, &BIND_EXPR_BODY (bind));
4213 append_to_statement_list (tf, &BIND_EXPR_BODY (bind));
4215 DECL_SAVED_TREE (fndecl) = bind;
4218 current_function_decl = oldfn;
4221 #include "gt-gimplify.h"