1 /* Tree lowering pass. This pass converts the GENERIC functions-as-trees
2 tree representation into the GIMPLE form.
3 Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
4 Major work done by Sebastian Pop <s.pop@laposte.net>,
5 Diego Novillo <dnovillo@redhat.com> and Jason Merrill <jason@redhat.com>.
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify it under
10 the terms of the GNU General Public License as published by the Free
11 Software Foundation; either version 2, or (at your option) any later
14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to the Free
21 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
26 #include "coretypes.h"
32 #include "tree-gimple.h"
33 #include "tree-inline.h"
34 #include "diagnostic.h"
35 #include "langhooks.h"
36 #include "langhooks-def.h"
37 #include "tree-flow.h"
50 static struct gimplify_ctx
52 tree current_bind_expr;
55 tree conditional_cleanups;
59 varray_type case_labels;
60 /* The formal temporary table. Should this be persistent? */
65 /* Formal (expression) temporary table handling: Multiple occurrences of
66 the same scalar expression are evaluated into the same temporary. */
68 typedef struct gimple_temp_hash_elt
71 tree temp; /* Value */
74 /* Forward declarations. */
75 static enum gimplify_status gimplify_compound_expr (tree *, tree *, bool);
78 /* Return a hash value for a formal temporary table entry. */
81 gimple_tree_hash (const void *p)
83 tree t = ((const elt_t *) p)->val;
84 return iterative_hash_expr (t, 0);
87 /* Compare two formal temporary table entries. */
90 gimple_tree_eq (const void *p1, const void *p2)
92 tree t1 = ((const elt_t *) p1)->val;
93 tree t2 = ((const elt_t *) p2)->val;
94 enum tree_code code = TREE_CODE (t1);
96 if (TREE_CODE (t2) != code
97 || TREE_TYPE (t1) != TREE_TYPE (t2))
100 if (!operand_equal_p (t1, t2, 0))
103 /* Only allow them to compare equal if they also hash equal; otherwise
104 results are nondeterminate, and we fail bootstrap comparison. */
105 if (gimple_tree_hash (p1) != gimple_tree_hash (p2))
111 /* Set up a context for the gimplifier. */
114 push_gimplify_context (void)
119 = (struct gimplify_ctx *) xcalloc (1, sizeof (struct gimplify_ctx));
120 gimplify_ctxp->temp_htab
121 = htab_create (1000, gimple_tree_hash, gimple_tree_eq, free);
124 /* Tear down a context for the gimplifier. If BODY is non-null, then
125 put the temporaries into the outer BIND_EXPR. Otherwise, put them
126 in the unexpanded_var_list. */
129 pop_gimplify_context (tree body)
131 if (!gimplify_ctxp || gimplify_ctxp->current_bind_expr)
135 declare_tmp_vars (gimplify_ctxp->temps, body);
137 record_vars (gimplify_ctxp->temps);
141 fprintf (stderr, " collisions: %f ",
142 htab_collisions (gimplify_ctxp->temp_htab));
145 htab_delete (gimplify_ctxp->temp_htab);
146 free (gimplify_ctxp);
147 gimplify_ctxp = NULL;
151 gimple_push_bind_expr (tree bind)
153 TREE_CHAIN (bind) = gimplify_ctxp->current_bind_expr;
154 gimplify_ctxp->current_bind_expr = bind;
158 gimple_pop_bind_expr (void)
160 gimplify_ctxp->current_bind_expr
161 = TREE_CHAIN (gimplify_ctxp->current_bind_expr);
165 gimple_current_bind_expr (void)
167 return gimplify_ctxp->current_bind_expr;
170 /* Returns true iff there is a COND_EXPR between us and the innermost
171 CLEANUP_POINT_EXPR. This info is used by gimple_push_cleanup. */
174 gimple_conditional_context (void)
176 return gimplify_ctxp->conditions > 0;
179 /* Note that we've entered a COND_EXPR. */
182 gimple_push_condition (void)
184 ++(gimplify_ctxp->conditions);
187 /* Note that we've left a COND_EXPR. If we're back at unconditional scope
188 now, add any conditional cleanups we've seen to the prequeue. */
191 gimple_pop_condition (tree *pre_p)
193 int conds = --(gimplify_ctxp->conditions);
197 append_to_statement_list (gimplify_ctxp->conditional_cleanups, pre_p);
198 gimplify_ctxp->conditional_cleanups = NULL_TREE;
204 /* A subroutine of append_to_statement_list{,_force}. */
207 append_to_statement_list_1 (tree t, tree *list_p, bool side_effects)
210 tree_stmt_iterator i;
217 if (t && TREE_CODE (t) == STATEMENT_LIST)
222 *list_p = list = alloc_stmt_list ();
226 tsi_link_after (&i, t, TSI_CONTINUE_LINKING);
229 /* Add T to the end of the list container pointed by LIST_P.
230 If T is an expression with no effects, it is ignored. */
233 append_to_statement_list (tree t, tree *list_p)
235 append_to_statement_list_1 (t, list_p, t ? TREE_SIDE_EFFECTS (t) : false);
238 /* Similar, but the statement is always added, regardless of side effects. */
241 append_to_statement_list_force (tree t, tree *list_p)
243 append_to_statement_list_1 (t, list_p, t != NULL);
246 /* Both gimplify the statement T and append it to LIST_P. */
249 gimplify_and_add (tree t, tree *list_p)
252 append_to_statement_list (t, list_p);
255 /* Strip off a legitimate source ending from the input string NAME of
256 length LEN. Rather than having to know the names used by all of
257 our front ends, we strip off an ending of a period followed by
258 up to five characters. (Java uses ".class".) */
261 remove_suffix (char *name, int len)
265 for (i = 2; i < 8 && len > i; i++)
267 if (name[len - i] == '.')
269 name[len - i] = '\0';
275 /* Create a nameless artificial label and put it in the current function
276 context. Returns the newly created label. */
279 create_artificial_label (void)
281 tree lab = build_decl (LABEL_DECL, NULL_TREE, void_type_node);
283 DECL_ARTIFICIAL (lab) = 1;
284 DECL_CONTEXT (lab) = current_function_decl;
288 /* Create a new temporary name with PREFIX. Returns an identifier. */
290 static GTY(()) unsigned int tmp_var_id_num;
293 create_tmp_var_name (const char *prefix)
299 char *preftmp = ASTRDUP (prefix);
301 remove_suffix (preftmp, strlen (preftmp));
305 ASM_FORMAT_PRIVATE_NAME (tmp_name, prefix ? prefix : "T", tmp_var_id_num++);
306 return get_identifier (tmp_name);
310 /* Create a new temporary variable declaration of type TYPE.
311 Does NOT push it into the current binding. */
314 create_tmp_var_raw (tree type, const char *prefix)
319 /* Make the type of the variable writable. */
320 new_type = build_type_variant (type, 0, 0);
321 TYPE_ATTRIBUTES (new_type) = TYPE_ATTRIBUTES (type);
323 tmp_var = build_decl (VAR_DECL, create_tmp_var_name (prefix), type);
325 /* The variable was declared by the compiler. */
326 DECL_ARTIFICIAL (tmp_var) = 1;
327 /* And we don't want debug info for it. */
328 DECL_IGNORED_P (tmp_var) = 1;
330 /* Make the variable writable. */
331 TREE_READONLY (tmp_var) = 0;
333 DECL_EXTERNAL (tmp_var) = 0;
334 TREE_STATIC (tmp_var) = 0;
335 TREE_USED (tmp_var) = 1;
340 /* Create a new temporary variable declaration of type TYPE. DOES push the
341 variable into the current binding. Further, assume that this is called
342 only from gimplification or optimization, at which point the creation of
343 certain types are bugs. */
346 create_tmp_var (tree type, const char *prefix)
350 #if defined ENABLE_CHECKING
351 /* We don't allow types that are addressable (meaning we can't make copies),
352 incomplete, or of variable size. */
353 if (TREE_ADDRESSABLE (type)
354 || !COMPLETE_TYPE_P (type)
355 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST)
359 tmp_var = create_tmp_var_raw (type, prefix);
360 gimple_add_tmp_var (tmp_var);
364 /* Given a tree, try to return a useful variable name that we can use
365 to prefix a temporary that is being assigned the value of the tree.
366 I.E. given <temp> = &A, return A. */
374 STRIP_NOPS (stripped_decl);
375 if (DECL_P (stripped_decl) && DECL_NAME (stripped_decl))
376 return IDENTIFIER_POINTER (DECL_NAME (stripped_decl));
379 switch (TREE_CODE (stripped_decl))
382 return get_name (TREE_OPERAND (stripped_decl, 0));
390 /* Create a temporary with a name derived from VAL. Subroutine of
391 lookup_tmp_var; nobody else should call this function. */
394 create_tmp_from_val (tree val)
396 return create_tmp_var (TREE_TYPE (val), get_name (val));
399 /* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse
400 an existing expression temporary. */
403 lookup_tmp_var (tree val, bool is_formal)
405 if (!is_formal || TREE_SIDE_EFFECTS (val))
406 return create_tmp_from_val (val);
413 slot = htab_find_slot (gimplify_ctxp->temp_htab, (void *)&elt, INSERT);
416 elt_p = xmalloc (sizeof (*elt_p));
418 elt_p->temp = create_tmp_from_val (val);
419 TREE_READONLY (elt_p->temp) = 1;
420 *slot = (void *) elt_p;
423 elt_p = (elt_t *) *slot;
429 /* Returns a formal temporary variable initialized with VAL. PRE_P is as
430 in gimplify_expr. Only use this function if:
432 1) The value of the unfactored expression represented by VAL will not
433 change between the initialization and use of the temporary, and
434 2) The temporary will not be otherwise modified.
436 For instance, #1 means that this is inappropriate for SAVE_EXPR temps,
437 and #2 means it is inappropriate for && temps.
439 For other cases, use get_initialized_tmp_var instead. */
442 internal_get_tmp_var (tree val, tree *pre_p, tree *post_p, bool is_formal)
447 gimplify_expr (&val, pre_p, post_p, is_gimple_tmp_rhs, fb_rvalue);
449 t = lookup_tmp_var (val, is_formal);
451 mod = build (MODIFY_EXPR, TREE_TYPE (t), t, val);
453 class = TREE_CODE_CLASS (TREE_CODE (val));
454 if (EXPR_HAS_LOCATION (val))
455 SET_EXPR_LOCUS (mod, EXPR_LOCUS (val));
457 SET_EXPR_LOCATION (mod, input_location);
459 /* gimplify_modify_expr might want to reduce this further. */
460 gimplify_and_add (mod, pre_p);
465 get_formal_tmp_var (tree val, tree *pre_p)
467 return internal_get_tmp_var (val, pre_p, NULL, true);
470 /* Returns a temporary variable initialized with VAL. PRE_P and POST_P
471 are as in gimplify_expr. */
474 get_initialized_tmp_var (tree val, tree *pre_p, tree *post_p)
476 return internal_get_tmp_var (val, pre_p, post_p, false);
479 /* Declares all the variables in VARS in SCOPE. */
482 declare_tmp_vars (tree vars, tree scope)
489 /* C99 mode puts the default 'return 0;' for main outside the outer
490 braces. So drill down until we find an actual scope. */
491 while (TREE_CODE (scope) == COMPOUND_EXPR)
492 scope = TREE_OPERAND (scope, 0);
494 if (TREE_CODE (scope) != BIND_EXPR)
497 temps = nreverse (last);
498 TREE_CHAIN (last) = BIND_EXPR_VARS (scope);
499 BIND_EXPR_VARS (scope) = temps;
504 gimple_add_tmp_var (tree tmp)
506 if (TREE_CHAIN (tmp) || DECL_SEEN_IN_BIND_EXPR_P (tmp))
509 DECL_CONTEXT (tmp) = current_function_decl;
510 DECL_SEEN_IN_BIND_EXPR_P (tmp) = 1;
514 TREE_CHAIN (tmp) = gimplify_ctxp->temps;
515 gimplify_ctxp->temps = tmp;
520 declare_tmp_vars (tmp, DECL_SAVED_TREE (current_function_decl));
523 /* Determines whether to assign a locus to the statement STMT. */
526 should_carry_locus_p (tree stmt)
528 /* Don't emit a line note for a label. We particularly don't want to
529 emit one for the break label, since it doesn't actually correspond
530 to the beginning of the loop/switch. */
531 if (TREE_CODE (stmt) == LABEL_EXPR)
534 /* Do not annotate empty statements, since it confuses gcov. */
535 if (!TREE_SIDE_EFFECTS (stmt))
542 annotate_one_with_locus (tree t, location_t locus)
544 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (t)))
545 && ! EXPR_HAS_LOCATION (t)
546 && should_carry_locus_p (t))
547 SET_EXPR_LOCATION (t, locus);
551 annotate_all_with_locus (tree *stmt_p, location_t locus)
553 tree_stmt_iterator i;
558 for (i = tsi_start (*stmt_p); !tsi_end_p (i); tsi_next (&i))
560 tree t = tsi_stmt (i);
562 #ifdef ENABLE_CHECKING
563 /* Assuming we've already been gimplified, we shouldn't
564 see nested chaining constructs anymore. */
565 if (TREE_CODE (t) == STATEMENT_LIST
566 || TREE_CODE (t) == COMPOUND_EXPR)
570 annotate_one_with_locus (t, locus);
574 /* Similar to copy_tree_r() but do not copy SAVE_EXPR or TARGET_EXPR nodes.
575 These nodes model computations that should only be done once. If we
576 were to unshare something like SAVE_EXPR(i++), the gimplification
577 process would create wrong code. */
580 mostly_copy_tree_r (tree *tp, int *walk_subtrees, void *data)
582 enum tree_code code = TREE_CODE (*tp);
583 /* Don't unshare types, decls, constants and SAVE_EXPR nodes. */
584 if (TREE_CODE_CLASS (code) == 't'
585 || TREE_CODE_CLASS (code) == 'd'
586 || TREE_CODE_CLASS (code) == 'c'
587 || code == SAVE_EXPR || code == TARGET_EXPR
588 /* We can't do anything sensible with a BLOCK used as an expression,
589 but we also can't abort when we see it because of non-expression
590 uses. So just avert our eyes and cross our fingers. Silly Java. */
593 else if (code == BIND_EXPR)
596 copy_tree_r (tp, walk_subtrees, data);
601 /* Callback for walk_tree to unshare most of the shared trees rooted at
602 *TP. If *TP has been visited already (i.e., TREE_VISITED (*TP) == 1),
603 then *TP is deep copied by calling copy_tree_r.
605 This unshares the same trees as copy_tree_r with the exception of
606 SAVE_EXPR nodes. These nodes model computations that should only be
607 done once. If we were to unshare something like SAVE_EXPR(i++), the
608 gimplification process would create wrong code. */
611 copy_if_shared_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
612 void *data ATTRIBUTE_UNUSED)
615 enum tree_code code = TREE_CODE (t);
617 /* Skip types, decls, and constants. But we do want to look at their
618 types and the bounds of types. Mark them as visited so we properly
619 unmark their subtrees on the unmark pass. If we've already seen them,
620 don't look down further. */
621 if (TREE_CODE_CLASS (code) == 't'
622 || TREE_CODE_CLASS (code) == 'd'
623 || TREE_CODE_CLASS (code) == 'c')
625 if (TREE_VISITED (t))
628 TREE_VISITED (t) = 1;
631 /* If this node has been visited already, unshare it and don't look
633 else if (TREE_VISITED (t))
635 walk_tree (tp, mostly_copy_tree_r, NULL, NULL);
639 /* Otherwise, mark the tree as visited and keep looking. */
641 TREE_VISITED (t) = 1;
647 unmark_visited_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
648 void *data ATTRIBUTE_UNUSED)
650 if (TREE_VISITED (*tp))
651 TREE_VISITED (*tp) = 0;
658 /* Unshare all the trees in BODY_P, a pointer into the body of FNDECL, and the
659 bodies of any nested functions if we are unsharing the entire body of
663 unshare_body (tree *body_p, tree fndecl)
665 struct cgraph_node *cgn = cgraph_node (fndecl);
667 walk_tree (body_p, copy_if_shared_r, NULL, NULL);
668 if (body_p == &DECL_SAVED_TREE (fndecl))
669 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
670 unshare_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
673 /* Likewise, but mark all trees as not visited. */
676 unvisit_body (tree *body_p, tree fndecl)
678 struct cgraph_node *cgn = cgraph_node (fndecl);
680 walk_tree (body_p, unmark_visited_r, NULL, NULL);
681 if (body_p == &DECL_SAVED_TREE (fndecl))
682 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
683 unvisit_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
686 /* Unshare T and all the trees reached from T via TREE_CHAIN. */
689 unshare_all_trees (tree t)
691 walk_tree (&t, copy_if_shared_r, NULL, NULL);
692 walk_tree (&t, unmark_visited_r, NULL, NULL);
695 /* Unconditionally make an unshared copy of EXPR. This is used when using
696 stored expressions which span multiple functions, such as BINFO_VTABLE,
697 as the normal unsharing process can't tell that they're shared. */
700 unshare_expr (tree expr)
702 walk_tree (&expr, mostly_copy_tree_r, NULL, NULL);
706 /* A terser interface for building a representation of a exception
710 gimple_build_eh_filter (tree body, tree allowed, tree failure)
714 /* FIXME should the allowed types go in TREE_TYPE? */
715 t = build (EH_FILTER_EXPR, void_type_node, allowed, NULL_TREE);
716 append_to_statement_list (failure, &EH_FILTER_FAILURE (t));
718 t = build (TRY_CATCH_EXPR, void_type_node, NULL_TREE, t);
719 append_to_statement_list (body, &TREE_OPERAND (t, 0));
725 /* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
726 contain statements and have a value. Assign its value to a temporary
727 and give it void_type_node. Returns the temporary, or NULL_TREE if
728 WRAPPER was already void. */
731 voidify_wrapper_expr (tree wrapper, tree temp)
733 if (!VOID_TYPE_P (TREE_TYPE (wrapper)))
735 tree *p, sub = wrapper;
738 /* Set p to point to the body of the wrapper. */
739 switch (TREE_CODE (sub))
742 /* For a BIND_EXPR, the body is operand 1. */
743 p = &BIND_EXPR_BODY (sub);
747 p = &TREE_OPERAND (sub, 0);
751 /* Advance to the last statement. Set all container types to void. */
752 if (TREE_CODE (*p) == STATEMENT_LIST)
754 tree_stmt_iterator i = tsi_last (*p);
755 p = tsi_end_p (i) ? NULL : tsi_stmt_ptr (i);
759 for (; TREE_CODE (*p) == COMPOUND_EXPR; p = &TREE_OPERAND (*p, 1))
761 TREE_SIDE_EFFECTS (*p) = 1;
762 TREE_TYPE (*p) = void_type_node;
766 if (p == NULL || IS_EMPTY_STMT (*p))
768 /* Look through exception handling. */
769 else if (TREE_CODE (*p) == TRY_FINALLY_EXPR
770 || TREE_CODE (*p) == TRY_CATCH_EXPR)
775 /* The C++ frontend already did this for us. */
776 else if (TREE_CODE (*p) == INIT_EXPR
777 || TREE_CODE (*p) == TARGET_EXPR)
778 temp = TREE_OPERAND (*p, 0);
779 /* If we're returning a dereference, move the dereference
780 outside the wrapper. */
781 else if (TREE_CODE (*p) == INDIRECT_REF)
783 tree ptr = TREE_OPERAND (*p, 0);
784 temp = create_tmp_var (TREE_TYPE (ptr), "retval");
785 *p = build (MODIFY_EXPR, TREE_TYPE (ptr), temp, ptr);
786 temp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (temp)), temp);
787 /* If this is a BIND_EXPR for a const inline function, it might not
788 have TREE_SIDE_EFFECTS set. That is no longer accurate. */
789 TREE_SIDE_EFFECTS (wrapper) = 1;
794 temp = create_tmp_var (TREE_TYPE (wrapper), "retval");
795 *p = build (MODIFY_EXPR, TREE_TYPE (temp), temp, *p);
796 TREE_SIDE_EFFECTS (wrapper) = 1;
799 TREE_TYPE (wrapper) = void_type_node;
806 /* Prepare calls to builtins to SAVE and RESTORE the stack as well as
807 a temporary through which they communicate. */
810 build_stack_save_restore (tree *save, tree *restore)
812 tree save_call, tmp_var;
815 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_SAVE],
817 tmp_var = create_tmp_var (ptr_type_node, "saved_stack");
819 *save = build (MODIFY_EXPR, ptr_type_node, tmp_var, save_call);
821 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_RESTORE],
822 tree_cons (NULL_TREE, tmp_var, NULL_TREE));
825 /* Gimplify a BIND_EXPR. Just voidify and recurse. */
827 static enum gimplify_status
828 gimplify_bind_expr (tree *expr_p, tree temp, tree *pre_p)
830 tree bind_expr = *expr_p;
831 bool old_save_stack = gimplify_ctxp->save_stack;
834 temp = voidify_wrapper_expr (bind_expr, temp);
836 /* Mark variables seen in this bind expr. */
837 for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t))
838 DECL_SEEN_IN_BIND_EXPR_P (t) = 1;
840 gimple_push_bind_expr (bind_expr);
841 gimplify_ctxp->save_stack = false;
843 gimplify_to_stmt_list (&BIND_EXPR_BODY (bind_expr));
845 if (gimplify_ctxp->save_stack)
847 tree stack_save, stack_restore;
849 /* Save stack on entry and restore it on exit. Add a try_finally
850 block to achieve this. Note that mudflap depends on the
851 format of the emitted code: see mx_register_decls(). */
852 build_stack_save_restore (&stack_save, &stack_restore);
854 t = build (TRY_FINALLY_EXPR, void_type_node,
855 BIND_EXPR_BODY (bind_expr), NULL_TREE);
856 append_to_statement_list (stack_restore, &TREE_OPERAND (t, 1));
858 BIND_EXPR_BODY (bind_expr) = NULL_TREE;
859 append_to_statement_list (stack_save, &BIND_EXPR_BODY (bind_expr));
860 append_to_statement_list (t, &BIND_EXPR_BODY (bind_expr));
863 gimplify_ctxp->save_stack = old_save_stack;
864 gimple_pop_bind_expr ();
869 append_to_statement_list (bind_expr, pre_p);
876 /* Gimplify a RETURN_EXPR. If the expression to be returned is not a
877 GIMPLE value, it is assigned to a new temporary and the statement is
878 re-written to return the temporary.
880 PRE_P points to the list where side effects that must happen before
881 STMT should be stored. */
883 static enum gimplify_status
884 gimplify_return_expr (tree stmt, tree *pre_p)
886 tree ret_expr = TREE_OPERAND (stmt, 0);
887 tree result_decl, result;
889 if (!ret_expr || TREE_CODE (ret_expr) == RESULT_DECL
890 || ret_expr == error_mark_node)
893 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
894 result_decl = NULL_TREE;
897 result_decl = TREE_OPERAND (ret_expr, 0);
898 #ifdef ENABLE_CHECKING
899 if ((TREE_CODE (ret_expr) != MODIFY_EXPR
900 && TREE_CODE (ret_expr) != INIT_EXPR)
901 || TREE_CODE (result_decl) != RESULT_DECL)
906 /* If aggregate_value_p is true, then we can return the bare RESULT_DECL.
907 Recall that aggregate_value_p is FALSE for any aggregate type that is
908 returned in registers. If we're returning values in registers, then
909 we don't want to extend the lifetime of the RESULT_DECL, particularly
910 across another call. In addition, for those aggregates for which
911 hard_function_value generates a PARALLEL, we'll abort during normal
912 expansion of structure assignments; there's special code in expand_return
913 to handle this case that does not exist in expand_expr. */
915 || aggregate_value_p (result_decl, TREE_TYPE (current_function_decl)))
916 result = result_decl;
917 else if (gimplify_ctxp->return_temp)
918 result = gimplify_ctxp->return_temp;
921 result = create_tmp_var (TREE_TYPE (result_decl), NULL);
923 /* ??? With complex control flow (usually involving abnormal edges),
924 we can wind up warning about an uninitialized value for this. Due
925 to how this variable is constructed and initialized, this is never
926 true. Give up and never warn. */
927 TREE_NO_WARNING (result) = 1;
929 gimplify_ctxp->return_temp = result;
932 /* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
933 Then gimplify the whole thing. */
934 if (result != result_decl)
935 TREE_OPERAND (ret_expr, 0) = result;
937 gimplify_and_add (TREE_OPERAND (stmt, 0), pre_p);
939 /* If we didn't use a temporary, then the result is just the result_decl.
940 Otherwise we need a simple copy. This should already be gimple. */
941 if (result == result_decl)
944 ret_expr = build (MODIFY_EXPR, TREE_TYPE (result), result_decl, result);
945 TREE_OPERAND (stmt, 0) = ret_expr;
950 /* Gimplifies a DECL_EXPR node *STMT_P by making any necessary allocation
951 and initialization explicit. */
953 static enum gimplify_status
954 gimplify_decl_expr (tree *stmt_p)
957 tree decl = DECL_EXPR_DECL (stmt);
961 if (TREE_TYPE (decl) == error_mark_node)
964 else if (TREE_CODE (decl) == TYPE_DECL)
965 gimplify_type_sizes (TREE_TYPE (decl), stmt_p);
967 else if (TREE_CODE (decl) == VAR_DECL && !DECL_EXTERNAL (decl))
969 tree init = DECL_INITIAL (decl);
971 if (!TREE_CONSTANT (DECL_SIZE (decl)))
973 /* This is a variable-sized decl. Simplify its size and mark it
974 for deferred expansion. Note that mudflap depends on the format
975 of the emitted code: see mx_register_decls(). */
978 gimplify_type_sizes (TREE_TYPE (decl), stmt_p);
979 gimplify_one_sizepos (&DECL_SIZE (decl), stmt_p);
980 gimplify_one_sizepos (&DECL_SIZE_UNIT (decl), stmt_p);
982 args = tree_cons (NULL, DECL_SIZE_UNIT (decl), NULL);
983 t = build_fold_addr_expr (decl);
984 args = tree_cons (NULL, t, args);
985 t = implicit_built_in_decls[BUILT_IN_STACK_ALLOC];
986 t = build_function_call_expr (t, args);
988 gimplify_and_add (t, stmt_p);
989 DECL_DEFER_OUTPUT (decl) = 1;
992 if (init && init != error_mark_node)
994 if (!TREE_STATIC (decl))
996 DECL_INITIAL (decl) = NULL_TREE;
997 init = build (MODIFY_EXPR, void_type_node, decl, init);
998 gimplify_and_add (init, stmt_p);
1001 /* We must still examine initializers for static variables
1002 as they may contain a label address. */
1003 walk_tree (&init, force_labels_r, NULL, NULL);
1006 /* This decl isn't mentioned in the enclosing block, so add it to the
1007 list of temps. FIXME it seems a bit of a kludge to say that
1008 anonymous artificial vars aren't pushed, but everything else is. */
1009 if (DECL_ARTIFICIAL (decl) && DECL_NAME (decl) == NULL_TREE)
1010 gimple_add_tmp_var (decl);
1016 /* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body
1017 and replacing the LOOP_EXPR with goto, but if the loop contains an
1018 EXIT_EXPR, we need to append a label for it to jump to. */
1020 static enum gimplify_status
1021 gimplify_loop_expr (tree *expr_p, tree *pre_p)
1023 tree saved_label = gimplify_ctxp->exit_label;
1024 tree start_label = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
1025 tree jump_stmt = build_and_jump (&LABEL_EXPR_LABEL (start_label));
1027 append_to_statement_list (start_label, pre_p);
1029 gimplify_ctxp->exit_label = NULL_TREE;
1031 gimplify_and_add (LOOP_EXPR_BODY (*expr_p), pre_p);
1033 if (gimplify_ctxp->exit_label)
1035 append_to_statement_list (jump_stmt, pre_p);
1036 *expr_p = build1 (LABEL_EXPR, void_type_node, gimplify_ctxp->exit_label);
1039 *expr_p = jump_stmt;
1041 gimplify_ctxp->exit_label = saved_label;
1046 /* Compare two case labels. Because the front end should already have
1047 made sure that case ranges do not overlap, it is enough to only compare
1048 the CASE_LOW values of each case label. */
1051 compare_case_labels (const void *p1, const void *p2)
1053 tree case1 = *(tree *)p1;
1054 tree case2 = *(tree *)p2;
1056 return tree_int_cst_compare (CASE_LOW (case1), CASE_LOW (case2));
1059 /* Sort the case labels in LABEL_VEC in place in ascending order. */
1062 sort_case_labels (tree label_vec)
1064 size_t len = TREE_VEC_LENGTH (label_vec);
1065 tree default_case = TREE_VEC_ELT (label_vec, len - 1);
1067 if (CASE_LOW (default_case))
1071 /* The last label in the vector should be the default case
1073 for (i = 0; i < len; ++i)
1075 tree t = TREE_VEC_ELT (label_vec, i);
1079 TREE_VEC_ELT (label_vec, i) = TREE_VEC_ELT (label_vec, len - 1);
1080 TREE_VEC_ELT (label_vec, len - 1) = default_case;
1086 qsort (&TREE_VEC_ELT (label_vec, 0), len - 1, sizeof (tree),
1087 compare_case_labels);
1090 /* Gimplify a SWITCH_EXPR, and collect a TREE_VEC of the labels it can
1093 static enum gimplify_status
1094 gimplify_switch_expr (tree *expr_p, tree *pre_p)
1096 tree switch_expr = *expr_p;
1097 enum gimplify_status ret;
1099 ret = gimplify_expr (&SWITCH_COND (switch_expr), pre_p, NULL,
1100 is_gimple_val, fb_rvalue);
1102 if (SWITCH_BODY (switch_expr))
1104 varray_type labels, saved_labels;
1105 tree label_vec, default_case = NULL_TREE;
1108 /* If someone can be bothered to fill in the labels, they can
1109 be bothered to null out the body too. */
1110 if (SWITCH_LABELS (switch_expr))
1113 saved_labels = gimplify_ctxp->case_labels;
1114 VARRAY_TREE_INIT (gimplify_ctxp->case_labels, 8, "case_labels");
1116 gimplify_to_stmt_list (&SWITCH_BODY (switch_expr));
1118 labels = gimplify_ctxp->case_labels;
1119 gimplify_ctxp->case_labels = saved_labels;
1121 len = VARRAY_ACTIVE_SIZE (labels);
1123 for (i = 0; i < len; ++i)
1125 tree t = VARRAY_TREE (labels, i);
1128 /* The default case must be the last label in the list. */
1130 VARRAY_TREE (labels, i) = VARRAY_TREE (labels, len - 1);
1136 label_vec = make_tree_vec (len + 1);
1137 SWITCH_LABELS (*expr_p) = label_vec;
1138 append_to_statement_list (switch_expr, pre_p);
1142 /* If the switch has no default label, add one, so that we jump
1143 around the switch body. */
1144 default_case = build (CASE_LABEL_EXPR, void_type_node, NULL_TREE,
1145 NULL_TREE, create_artificial_label ());
1146 append_to_statement_list (SWITCH_BODY (switch_expr), pre_p);
1147 *expr_p = build (LABEL_EXPR, void_type_node,
1148 CASE_LABEL (default_case));
1151 *expr_p = SWITCH_BODY (switch_expr);
1153 for (i = 0; i < len; ++i)
1154 TREE_VEC_ELT (label_vec, i) = VARRAY_TREE (labels, i);
1155 TREE_VEC_ELT (label_vec, len) = default_case;
1157 sort_case_labels (label_vec);
1159 SWITCH_BODY (switch_expr) = NULL;
1161 else if (!SWITCH_LABELS (switch_expr))
1167 static enum gimplify_status
1168 gimplify_case_label_expr (tree *expr_p)
1170 tree expr = *expr_p;
1171 if (gimplify_ctxp->case_labels)
1172 VARRAY_PUSH_TREE (gimplify_ctxp->case_labels, expr);
1175 *expr_p = build (LABEL_EXPR, void_type_node, CASE_LABEL (expr));
1179 /* Gimplify a LABELED_BLOCK_EXPR into a LABEL_EXPR following
1180 a (possibly empty) body. */
1182 static enum gimplify_status
1183 gimplify_labeled_block_expr (tree *expr_p)
1185 tree body = LABELED_BLOCK_BODY (*expr_p);
1186 tree label = LABELED_BLOCK_LABEL (*expr_p);
1189 DECL_CONTEXT (label) = current_function_decl;
1190 t = build (LABEL_EXPR, void_type_node, label);
1191 if (body != NULL_TREE)
1192 t = build (COMPOUND_EXPR, void_type_node, body, t);
1198 /* Gimplify a EXIT_BLOCK_EXPR into a GOTO_EXPR. */
1200 static enum gimplify_status
1201 gimplify_exit_block_expr (tree *expr_p)
1203 tree labeled_block = TREE_OPERAND (*expr_p, 0);
1206 /* First operand must be a LABELED_BLOCK_EXPR, which should
1207 already be lowered (or partially lowered) when we get here. */
1208 #if defined ENABLE_CHECKING
1209 if (TREE_CODE (labeled_block) != LABELED_BLOCK_EXPR)
1213 label = LABELED_BLOCK_LABEL (labeled_block);
1214 *expr_p = build1 (GOTO_EXPR, void_type_node, label);
1219 /* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
1223 build_and_jump (tree *label_p)
1225 if (label_p == NULL)
1226 /* If there's nowhere to jump, just fall through. */
1229 if (*label_p == NULL_TREE)
1231 tree label = create_artificial_label ();
1235 return build1 (GOTO_EXPR, void_type_node, *label_p);
1238 /* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
1239 This also involves building a label to jump to and communicating it to
1240 gimplify_loop_expr through gimplify_ctxp->exit_label. */
1242 static enum gimplify_status
1243 gimplify_exit_expr (tree *expr_p)
1245 tree cond = TREE_OPERAND (*expr_p, 0);
1248 expr = build_and_jump (&gimplify_ctxp->exit_label);
1249 expr = build (COND_EXPR, void_type_node, cond, expr, NULL_TREE);
1255 /* A helper function to be called via walk_tree. Mark all labels under *TP
1256 as being forced. To be called for DECL_INITIAL of static variables. */
1259 force_labels_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1263 if (TREE_CODE (*tp) == LABEL_DECL)
1264 FORCED_LABEL (*tp) = 1;
1269 /* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is
1270 different from its canonical type, wrap the whole thing inside a
1271 NOP_EXPR and force the type of the COMPONENT_REF to be the canonical
1274 The canonical type of a COMPONENT_REF is the type of the field being
1275 referenced--unless the field is a bit-field which can be read directly
1276 in a smaller mode, in which case the canonical type is the
1277 sign-appropriate type corresponding to that mode. */
1280 canonicalize_component_ref (tree *expr_p)
1282 tree expr = *expr_p;
1285 if (TREE_CODE (expr) != COMPONENT_REF)
1288 if (INTEGRAL_TYPE_P (TREE_TYPE (expr)))
1289 type = TREE_TYPE (get_unwidened (expr, NULL_TREE));
1291 type = TREE_TYPE (TREE_OPERAND (expr, 1));
1293 if (TREE_TYPE (expr) != type)
1295 tree old_type = TREE_TYPE (expr);
1297 /* Set the type of the COMPONENT_REF to the underlying type. */
1298 TREE_TYPE (expr) = type;
1300 /* And wrap the whole thing inside a NOP_EXPR. */
1301 expr = build1 (NOP_EXPR, old_type, expr);
1307 /* If a NOP conversion is changing a pointer to array of foo to a pointer
1308 to foo, embed that change in the ADDR_EXPR by converting
1313 where L is the lower bound. For simplicity, only do this for constant
1317 canonicalize_addr_expr (tree *expr_p)
1319 tree expr = *expr_p;
1320 tree ctype = TREE_TYPE (expr);
1321 tree addr_expr = TREE_OPERAND (expr, 0);
1322 tree atype = TREE_TYPE (addr_expr);
1323 tree dctype, datype, ddatype, otype, obj_expr;
1325 /* Both cast and addr_expr types should be pointers. */
1326 if (!POINTER_TYPE_P (ctype) || !POINTER_TYPE_P (atype))
1329 /* The addr_expr type should be a pointer to an array. */
1330 datype = TREE_TYPE (atype);
1331 if (TREE_CODE (datype) != ARRAY_TYPE)
1334 /* Both cast and addr_expr types should address the same object type. */
1335 dctype = TREE_TYPE (ctype);
1336 ddatype = TREE_TYPE (datype);
1337 if (!lang_hooks.types_compatible_p (ddatype, dctype))
1340 /* The addr_expr and the object type should match. */
1341 obj_expr = TREE_OPERAND (addr_expr, 0);
1342 otype = TREE_TYPE (obj_expr);
1343 if (!lang_hooks.types_compatible_p (otype, datype))
1346 /* The lower bound and element sizes must be constant. */
1347 if (TREE_CODE (TYPE_SIZE_UNIT (dctype)) != INTEGER_CST
1348 || !TYPE_DOMAIN (datype) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype))
1349 || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype))) != INTEGER_CST)
1352 /* All checks succeeded. Build a new node to merge the cast. */
1353 *expr_p = build4 (ARRAY_REF, dctype, obj_expr,
1354 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1355 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1356 size_binop (EXACT_DIV_EXPR, TYPE_SIZE_UNIT (dctype),
1357 size_int (TYPE_ALIGN (dctype)
1359 *expr_p = build1 (ADDR_EXPR, ctype, *expr_p);
1362 /* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
1363 underneath as appropriate. */
1365 static enum gimplify_status
1366 gimplify_conversion (tree *expr_p)
1368 /* If we still have a conversion at the toplevel, then strip
1369 away all but the outermost conversion. */
1370 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1372 STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0));
1374 /* And remove the outermost conversion if it's useless. */
1375 if (tree_ssa_useless_type_conversion (*expr_p))
1376 *expr_p = TREE_OPERAND (*expr_p, 0);
1379 /* If we still have a conversion at the toplevel,
1380 then canonicalize some constructs. */
1381 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1383 tree sub = TREE_OPERAND (*expr_p, 0);
1385 /* If a NOP conversion is changing the type of a COMPONENT_REF
1386 expression, then canonicalize its type now in order to expose more
1387 redundant conversions. */
1388 if (TREE_CODE (sub) == COMPONENT_REF)
1389 canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0));
1391 /* If a NOP conversion is changing a pointer to array of foo
1392 to a pointer to foo, embed that change in the ADDR_EXPR. */
1393 else if (TREE_CODE (sub) == ADDR_EXPR)
1394 canonicalize_addr_expr (expr_p);
1400 /* Reduce MIN/MAX_EXPR to a COND_EXPR for further gimplification. */
1402 static enum gimplify_status
1403 gimplify_minimax_expr (tree *expr_p, tree *pre_p, tree *post_p)
1405 tree op1 = TREE_OPERAND (*expr_p, 0);
1406 tree op2 = TREE_OPERAND (*expr_p, 1);
1407 enum tree_code code;
1408 enum gimplify_status r0, r1;
1410 if (TREE_CODE (*expr_p) == MIN_EXPR)
1415 r0 = gimplify_expr (&op1, pre_p, post_p, is_gimple_val, fb_rvalue);
1416 r1 = gimplify_expr (&op2, pre_p, post_p, is_gimple_val, fb_rvalue);
1418 *expr_p = build (COND_EXPR, TREE_TYPE (*expr_p),
1419 build (code, boolean_type_node, op1, op2),
1422 if (r0 == GS_ERROR || r1 == GS_ERROR)
1428 /* Subroutine of gimplify_compound_lval.
1429 Converts an ARRAY_REF to the equivalent *(&array + offset) form. */
1431 static enum gimplify_status
1432 gimplify_array_ref_to_plus (tree *expr_p, tree *pre_p, tree *post_p)
1434 tree array = TREE_OPERAND (*expr_p, 0);
1435 tree arrtype = TREE_TYPE (array);
1436 tree elttype = TREE_TYPE (arrtype);
1437 tree size = array_ref_element_size (*expr_p);
1438 tree ptrtype = build_pointer_type (elttype);
1439 enum tree_code add_code = PLUS_EXPR;
1440 tree idx = TREE_OPERAND (*expr_p, 1);
1441 tree minidx = unshare_expr (array_ref_low_bound (*expr_p));
1442 tree offset, addr, result;
1443 enum gimplify_status ret;
1445 /* If the array domain does not start at zero, apply the offset. */
1446 if (!integer_zerop (minidx))
1448 idx = convert (TREE_TYPE (minidx), idx);
1449 idx = fold (build (MINUS_EXPR, TREE_TYPE (minidx), idx, minidx));
1452 /* If the index is negative -- a technically invalid situation now
1453 that we've biased the index back to zero -- then casting it to
1454 unsigned has ill effects. In particular, -1*4U/4U != -1.
1455 Represent this as a subtraction of a positive rather than addition
1456 of a negative. This will prevent any conversion back to ARRAY_REF
1457 from getting the wrong results from the division. */
1458 if (TREE_CODE (idx) == INTEGER_CST && tree_int_cst_sgn (idx) < 0)
1460 idx = fold (build1 (NEGATE_EXPR, TREE_TYPE (idx), idx));
1461 add_code = MINUS_EXPR;
1464 /* Pointer arithmetic must be done in sizetype. */
1465 idx = fold_convert (sizetype, idx);
1467 /* Convert the index to a byte offset. */
1468 offset = size_binop (MULT_EXPR, size, idx);
1470 ret = gimplify_expr (&array, pre_p, post_p, is_gimple_min_lval, fb_lvalue);
1471 if (ret == GS_ERROR)
1474 addr = build_fold_addr_expr_with_type (array, ptrtype);
1475 result = fold (build (add_code, ptrtype, addr, offset));
1476 *expr_p = build1 (INDIRECT_REF, elttype, result);
1481 /* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
1482 node pointed by EXPR_P.
1485 : min_lval '[' val ']'
1487 | compound_lval '[' val ']'
1488 | compound_lval '.' ID
1490 This is not part of the original SIMPLE definition, which separates
1491 array and member references, but it seems reasonable to handle them
1492 together. Also, this way we don't run into problems with union
1493 aliasing; gcc requires that for accesses through a union to alias, the
1494 union reference must be explicit, which was not always the case when we
1495 were splitting up array and member refs.
1497 PRE_P points to the list where side effects that must happen before
1498 *EXPR_P should be stored.
1500 POST_P points to the list where side effects that must happen after
1501 *EXPR_P should be stored. */
1503 static enum gimplify_status
1504 gimplify_compound_lval (tree *expr_p, tree *pre_p,
1505 tree *post_p, fallback_t fallback)
1509 enum gimplify_status ret = GS_OK, tret;
1512 #if defined ENABLE_CHECKING
1513 if (TREE_CODE (*expr_p) != ARRAY_REF
1514 && TREE_CODE (*expr_p) != ARRAY_RANGE_REF
1515 && TREE_CODE (*expr_p) != COMPONENT_REF
1516 && TREE_CODE (*expr_p) != BIT_FIELD_REF
1517 && TREE_CODE (*expr_p) != REALPART_EXPR
1518 && TREE_CODE (*expr_p) != IMAGPART_EXPR)
1522 /* Create a stack of the subexpressions so later we can walk them in
1523 order from inner to outer. */
1524 VARRAY_TREE_INIT (stack, 10, "stack");
1526 /* We can either handle REALPART_EXPR, IMAGEPART_EXPR anything that
1527 handled_components can deal with. */
1529 (handled_component_p (*p)
1530 || TREE_CODE (*p) == REALPART_EXPR || TREE_CODE (*p) == IMAGPART_EXPR);
1531 p = &TREE_OPERAND (*p, 0))
1532 VARRAY_PUSH_TREE (stack, *p);
1534 /* Now STACK is a stack of pointers to all the refs we've walked through
1535 and P points to the innermost expression.
1537 Java requires that we elaborated nodes in source order. That
1538 means we must gimplify the inner expression followed by each of
1539 the indices, in order. But we can't gimplify the inner
1540 expression until we deal with any variable bounds, sizes, or
1541 positions in order to deal with PLACEHOLDER_EXPRs.
1543 So we do this in three steps. First we deal with the annotations
1544 for any variables in the components, then we gimplify the base,
1545 then we gimplify any indices, from left to right. */
1546 for (i = VARRAY_ACTIVE_SIZE (stack) - 1; i >= 0; i--)
1548 tree t = VARRAY_TREE (stack, i);
1550 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1552 /* Gimplify the low bound and element type size and put them into
1553 the ARRAY_REF. If these values are set, they have already been
1555 if (!TREE_OPERAND (t, 2))
1557 tree low = unshare_expr (array_ref_low_bound (t));
1558 if (!is_gimple_min_invariant (low))
1560 TREE_OPERAND (t, 2) = low;
1561 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1562 is_gimple_tmp_reg, fb_rvalue);
1563 ret = MIN (ret, tret);
1567 if (!TREE_OPERAND (t, 3))
1569 tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
1570 tree elmt_size = unshare_expr (array_ref_element_size (t));
1571 tree factor = size_int (TYPE_ALIGN (elmt_type) / BITS_PER_UNIT);
1573 /* Divide the element size by the alignment of the element
1575 elmt_size = size_binop (EXACT_DIV_EXPR, elmt_size, factor);
1577 if (!is_gimple_min_invariant (elmt_size))
1579 TREE_OPERAND (t, 3) = elmt_size;
1580 tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p,
1581 is_gimple_tmp_reg, fb_rvalue);
1582 ret = MIN (ret, tret);
1586 else if (TREE_CODE (t) == COMPONENT_REF)
1588 /* Set the field offset into T and gimplify it. */
1589 if (!TREE_OPERAND (t, 2))
1591 tree offset = unshare_expr (component_ref_field_offset (t));
1592 tree field = TREE_OPERAND (t, 1);
1594 = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
1596 /* Divide the offset by its alignment. */
1597 offset = size_binop (EXACT_DIV_EXPR, offset, factor);
1599 if (!is_gimple_min_invariant (offset))
1601 TREE_OPERAND (t, 2) = offset;
1602 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1603 is_gimple_tmp_reg, fb_rvalue);
1604 ret = MIN (ret, tret);
1610 /* Step 2 is to gimplify the base expression. */
1611 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1612 ret = MIN (ret, tret);
1614 /* And finally, the indices and operands to BIT_FIELD_REF. During this
1615 loop we also remove any useless conversions. */
1616 for (; VARRAY_ACTIVE_SIZE (stack) > 0; )
1618 tree t = VARRAY_TOP_TREE (stack);
1620 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1622 /* Gimplify the dimension.
1623 Temporary fix for gcc.c-torture/execute/20040313-1.c.
1624 Gimplify non-constant array indices into a temporary
1626 FIXME - The real fix is to gimplify post-modify
1627 expressions into a minimal gimple lvalue. However, that
1628 exposes bugs in alias analysis. The alias analyzer does
1629 not handle &PTR->FIELD very well. Will fix after the
1630 branch is merged into mainline (dnovillo 2004-05-03). */
1631 if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
1633 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1634 is_gimple_tmp_reg, fb_rvalue);
1635 ret = MIN (ret, tret);
1638 else if (TREE_CODE (t) == BIT_FIELD_REF)
1640 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1641 is_gimple_val, fb_rvalue);
1642 ret = MIN (ret, tret);
1643 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1644 is_gimple_val, fb_rvalue);
1645 ret = MIN (ret, tret);
1648 STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0));
1650 /* The innermost expression P may have originally had TREE_SIDE_EFFECTS
1651 set which would have caused all the outer expressions in EXPR_P
1652 leading to P to also have had TREE_SIDE_EFFECTS set. */
1653 recalculate_side_effects (t);
1657 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1658 ret = MIN (ret, tret);
1660 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
1661 if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF)
1663 canonicalize_component_ref (expr_p);
1664 ret = MIN (ret, GS_OK);
1670 /* Gimplify the self modifying expression pointed by EXPR_P (++, --, +=, -=).
1672 PRE_P points to the list where side effects that must happen before
1673 *EXPR_P should be stored.
1675 POST_P points to the list where side effects that must happen after
1676 *EXPR_P should be stored.
1678 WANT_VALUE is nonzero iff we want to use the value of this expression
1679 in another expression. */
1681 static enum gimplify_status
1682 gimplify_self_mod_expr (tree *expr_p, tree *pre_p, tree *post_p,
1685 enum tree_code code;
1686 tree lhs, lvalue, rhs, t1;
1688 enum tree_code arith_code;
1689 enum gimplify_status ret;
1691 code = TREE_CODE (*expr_p);
1693 #if defined ENABLE_CHECKING
1694 if (code != POSTINCREMENT_EXPR
1695 && code != POSTDECREMENT_EXPR
1696 && code != PREINCREMENT_EXPR
1697 && code != PREDECREMENT_EXPR)
1701 /* Prefix or postfix? */
1702 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
1703 /* Faster to treat as prefix if result is not used. */
1704 postfix = want_value;
1708 /* Add or subtract? */
1709 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
1710 arith_code = PLUS_EXPR;
1712 arith_code = MINUS_EXPR;
1714 /* Gimplify the LHS into a GIMPLE lvalue. */
1715 lvalue = TREE_OPERAND (*expr_p, 0);
1716 ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
1717 if (ret == GS_ERROR)
1720 /* Extract the operands to the arithmetic operation. */
1722 rhs = TREE_OPERAND (*expr_p, 1);
1724 /* For postfix operator, we evaluate the LHS to an rvalue and then use
1725 that as the result value and in the postqueue operation. */
1728 ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
1729 if (ret == GS_ERROR)
1733 t1 = build (arith_code, TREE_TYPE (*expr_p), lhs, rhs);
1734 t1 = build (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
1738 gimplify_and_add (t1, post_p);
1749 /* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
1752 maybe_with_size_expr (tree *expr_p)
1754 tree expr, type, size;
1757 type = TREE_TYPE (expr);
1758 if (type == error_mark_node)
1761 size = TYPE_SIZE_UNIT (type);
1762 if (size && TREE_CODE (size) != INTEGER_CST)
1764 size = unshare_expr (size);
1765 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr);
1766 *expr_p = build2 (WITH_SIZE_EXPR, type, expr, size);
1770 /* Subroutine of gimplify_call_expr: Gimplify a single argument. */
1772 static enum gimplify_status
1773 gimplify_arg (tree *expr_p, tree *pre_p)
1775 bool (*test) (tree);
1778 /* In general, we allow lvalues for function arguments to avoid
1779 extra overhead of copying large aggregates out of even larger
1780 aggregates into temporaries only to copy the temporaries to
1781 the argument list. Make optimizers happy by pulling out to
1782 temporaries those types that fit in registers. */
1783 if (is_gimple_reg_type (TREE_TYPE (*expr_p)))
1784 test = is_gimple_val, fb = fb_rvalue;
1786 test = is_gimple_lvalue, fb = fb_either;
1788 /* If this is a variable sized type, we must remember the size. */
1789 maybe_with_size_expr (expr_p);
1791 /* There is a sequence point before a function call. Side effects in
1792 the argument list must occur before the actual call. So, when
1793 gimplifying arguments, force gimplify_expr to use an internal
1794 post queue which is then appended to the end of PRE_P. */
1795 return gimplify_expr (expr_p, pre_p, NULL, test, fb);
1798 /* Gimplify the CALL_EXPR node pointed by EXPR_P. PRE_P points to the
1799 list where side effects that must happen before *EXPR_P should be stored.
1800 WANT_VALUE is true if the result of the call is desired. */
1802 static enum gimplify_status
1803 gimplify_call_expr (tree *expr_p, tree *pre_p, bool want_value)
1807 enum gimplify_status ret;
1809 #if defined ENABLE_CHECKING
1810 if (TREE_CODE (*expr_p) != CALL_EXPR)
1814 /* For reliable diagnostics during inlining, it is necessary that
1815 every call_expr be annotated with file and line. */
1816 if (! EXPR_HAS_LOCATION (*expr_p))
1817 SET_EXPR_LOCATION (*expr_p, input_location);
1819 /* This may be a call to a builtin function.
1821 Builtin function calls may be transformed into different
1822 (and more efficient) builtin function calls under certain
1823 circumstances. Unfortunately, gimplification can muck things
1824 up enough that the builtin expanders are not aware that certain
1825 transformations are still valid.
1827 So we attempt transformation/gimplification of the call before
1828 we gimplify the CALL_EXPR. At this time we do not manage to
1829 transform all calls in the same manner as the expanders do, but
1830 we do transform most of them. */
1831 decl = get_callee_fndecl (*expr_p);
1832 if (decl && DECL_BUILT_IN (decl))
1836 /* If it is allocation of stack, record the need to restore the memory
1837 when the enclosing bind_expr is exited. */
1838 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_STACK_ALLOC)
1839 gimplify_ctxp->save_stack = true;
1841 /* If it is restore of the stack, reset it, since it means we are
1842 regimplifying the bind_expr. Note that we use the fact that
1843 for try_finally_expr, try part is processed first. */
1844 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_STACK_RESTORE)
1845 gimplify_ctxp->save_stack = false;
1847 new = simplify_builtin (*expr_p, !want_value);
1849 if (new && new != *expr_p)
1851 /* There was a transformation of this call which computes the
1852 same value, but in a more efficient way. Return and try
1858 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_VA_START)
1859 /* Avoid gimplifying the second argument to va_start, which needs
1860 to be the plain PARM_DECL. */
1861 return gimplify_arg (&TREE_VALUE (TREE_OPERAND (*expr_p, 1)), pre_p);
1864 /* There is a sequence point before the call, so any side effects in
1865 the calling expression must occur before the actual call. Force
1866 gimplify_expr to use an internal post queue. */
1867 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, NULL,
1868 is_gimple_call_addr, fb_rvalue);
1870 if (PUSH_ARGS_REVERSED)
1871 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1872 for (arglist = TREE_OPERAND (*expr_p, 1); arglist;
1873 arglist = TREE_CHAIN (arglist))
1875 enum gimplify_status t;
1877 t = gimplify_arg (&TREE_VALUE (arglist), pre_p);
1882 if (PUSH_ARGS_REVERSED)
1883 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1885 /* Try this again in case gimplification exposed something. */
1886 if (ret != GS_ERROR && decl && DECL_BUILT_IN (decl))
1888 tree new = simplify_builtin (*expr_p, !want_value);
1890 if (new && new != *expr_p)
1892 /* There was a transformation of this call which computes the
1893 same value, but in a more efficient way. Return and try
1900 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
1901 decl. This allows us to eliminate redundant or useless
1902 calls to "const" functions. */
1903 if (TREE_CODE (*expr_p) == CALL_EXPR
1904 && (call_expr_flags (*expr_p) & (ECF_CONST | ECF_PURE)))
1905 TREE_SIDE_EFFECTS (*expr_p) = 0;
1910 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
1911 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
1913 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
1914 condition is true or false, respectively. If null, we should generate
1915 our own to skip over the evaluation of this specific expression.
1917 This function is the tree equivalent of do_jump.
1919 shortcut_cond_r should only be called by shortcut_cond_expr. */
1922 shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p)
1924 tree local_label = NULL_TREE;
1925 tree t, expr = NULL;
1927 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
1928 retain the shortcut semantics. Just insert the gotos here;
1929 shortcut_cond_expr will append the real blocks later. */
1930 if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
1932 /* Turn if (a && b) into
1934 if (a); else goto no;
1935 if (b) goto yes; else goto no;
1938 if (false_label_p == NULL)
1939 false_label_p = &local_label;
1941 t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p);
1942 append_to_statement_list (t, &expr);
1944 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1946 append_to_statement_list (t, &expr);
1948 else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
1950 /* Turn if (a || b) into
1953 if (b) goto yes; else goto no;
1956 if (true_label_p == NULL)
1957 true_label_p = &local_label;
1959 t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL);
1960 append_to_statement_list (t, &expr);
1962 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1964 append_to_statement_list (t, &expr);
1966 else if (TREE_CODE (pred) == COND_EXPR)
1968 /* As long as we're messing with gotos, turn if (a ? b : c) into
1970 if (b) goto yes; else goto no;
1972 if (c) goto yes; else goto no; */
1973 expr = build (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
1974 shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1976 shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
1981 expr = build (COND_EXPR, void_type_node, pred,
1982 build_and_jump (true_label_p),
1983 build_and_jump (false_label_p));
1988 t = build1 (LABEL_EXPR, void_type_node, local_label);
1989 append_to_statement_list (t, &expr);
1996 shortcut_cond_expr (tree expr)
1998 tree pred = TREE_OPERAND (expr, 0);
1999 tree then_ = TREE_OPERAND (expr, 1);
2000 tree else_ = TREE_OPERAND (expr, 2);
2001 tree true_label, false_label, end_label, t;
2003 tree *false_label_p;
2004 bool emit_end, emit_false;
2005 bool then_se = then_ && TREE_SIDE_EFFECTS (then_);
2006 bool else_se = else_ && TREE_SIDE_EFFECTS (else_);
2008 /* First do simple transformations. */
2011 /* If there is no 'else', turn (a && b) into if (a) if (b). */
2012 while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2014 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2015 then_ = shortcut_cond_expr (expr);
2016 pred = TREE_OPERAND (pred, 0);
2017 expr = build (COND_EXPR, void_type_node, pred, then_, NULL_TREE);
2022 /* If there is no 'then', turn
2025 if (a); else if (b); else d. */
2026 while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2028 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2029 else_ = shortcut_cond_expr (expr);
2030 pred = TREE_OPERAND (pred, 0);
2031 expr = build (COND_EXPR, void_type_node, pred, NULL_TREE, else_);
2035 /* If we're done, great. */
2036 if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
2037 && TREE_CODE (pred) != TRUTH_ORIF_EXPR)
2040 /* Otherwise we need to mess with gotos. Change
2043 if (a); else goto no;
2046 and recursively gimplify the condition. */
2048 true_label = false_label = end_label = NULL_TREE;
2050 /* If our arms just jump somewhere, hijack those labels so we don't
2051 generate jumps to jumps. */
2054 && TREE_CODE (then_) == GOTO_EXPR
2055 && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
2057 true_label = GOTO_DESTINATION (then_);
2063 && TREE_CODE (else_) == GOTO_EXPR
2064 && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
2066 false_label = GOTO_DESTINATION (else_);
2071 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2073 true_label_p = &true_label;
2075 true_label_p = NULL;
2077 /* The 'else' branch also needs a label if it contains interesting code. */
2078 if (false_label || else_se)
2079 false_label_p = &false_label;
2081 false_label_p = NULL;
2083 /* If there was nothing else in our arms, just forward the label(s). */
2084 if (!then_se && !else_se)
2085 return shortcut_cond_r (pred, true_label_p, false_label_p);
2087 /* If our last subexpression already has a terminal label, reuse it. */
2089 expr = expr_last (else_);
2091 expr = expr_last (then_);
2094 if (expr && TREE_CODE (expr) == LABEL_EXPR)
2095 end_label = LABEL_EXPR_LABEL (expr);
2097 /* If we don't care about jumping to the 'else' branch, jump to the end
2098 if the condition is false. */
2100 false_label_p = &end_label;
2102 /* We only want to emit these labels if we aren't hijacking them. */
2103 emit_end = (end_label == NULL_TREE);
2104 emit_false = (false_label == NULL_TREE);
2106 pred = shortcut_cond_r (pred, true_label_p, false_label_p);
2109 append_to_statement_list (pred, &expr);
2111 append_to_statement_list (then_, &expr);
2114 t = build_and_jump (&end_label);
2115 append_to_statement_list (t, &expr);
2118 t = build1 (LABEL_EXPR, void_type_node, false_label);
2119 append_to_statement_list (t, &expr);
2121 append_to_statement_list (else_, &expr);
2123 if (emit_end && end_label)
2125 t = build1 (LABEL_EXPR, void_type_node, end_label);
2126 append_to_statement_list (t, &expr);
2132 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2135 gimple_boolify (tree expr)
2137 tree type = TREE_TYPE (expr);
2139 if (TREE_CODE (type) == BOOLEAN_TYPE)
2142 /* If this is the predicate of a COND_EXPR, it might not even be a
2144 expr = lang_hooks.truthvalue_conversion (expr);
2146 switch (TREE_CODE (expr))
2148 case TRUTH_AND_EXPR:
2150 case TRUTH_XOR_EXPR:
2151 case TRUTH_ANDIF_EXPR:
2152 case TRUTH_ORIF_EXPR:
2153 /* Also boolify the arguments of truth exprs. */
2154 TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
2157 case TRUTH_NOT_EXPR:
2158 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2161 case EQ_EXPR: case NE_EXPR:
2162 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2163 /* These expressions always produce boolean results. */
2164 TREE_TYPE (expr) = boolean_type_node;
2168 /* Other expressions that get here must have boolean values, but
2169 might need to be converted to the appropriate mode. */
2170 return convert (boolean_type_node, expr);
2174 /* Convert the conditional expression pointed by EXPR_P '(p) ? a : b;'
2183 The second form is used when *EXPR_P is of type void.
2185 TARGET is the tree for T1 above.
2187 PRE_P points to the list where side effects that must happen before
2188 *EXPR_P should be stored. */
2190 static enum gimplify_status
2191 gimplify_cond_expr (tree *expr_p, tree *pre_p, tree target)
2193 tree expr = *expr_p;
2195 enum gimplify_status ret;
2197 type = TREE_TYPE (expr);
2199 TREE_TYPE (expr) = void_type_node;
2201 /* If this COND_EXPR has a value, copy the values into a temporary within
2203 else if (! VOID_TYPE_P (type))
2212 tmp = create_tmp_var (TREE_TYPE (expr), "iftmp");
2216 /* Build the then clause, 't1 = a;'. But don't build an assignment
2217 if this branch is void; in C++ it can be, if it's a throw. */
2218 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2219 TREE_OPERAND (expr, 1)
2220 = build (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 1));
2222 /* Build the else clause, 't1 = b;'. */
2223 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2224 TREE_OPERAND (expr, 2)
2225 = build (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 2));
2227 TREE_TYPE (expr) = void_type_node;
2228 recalculate_side_effects (expr);
2230 /* Move the COND_EXPR to the prequeue and use the temp in its place. */
2231 gimplify_and_add (expr, pre_p);
2237 /* Make sure the condition has BOOLEAN_TYPE. */
2238 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2240 /* Break apart && and || conditions. */
2241 if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
2242 || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
2244 expr = shortcut_cond_expr (expr);
2246 if (expr != *expr_p)
2250 /* We can't rely on gimplify_expr to re-gimplify the expanded
2251 form properly, as cleanups might cause the target labels to be
2252 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2253 set up a conditional context. */
2254 gimple_push_condition ();
2255 gimplify_stmt (expr_p);
2256 gimple_pop_condition (pre_p);
2262 /* Now do the normal gimplification. */
2263 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2264 is_gimple_condexpr, fb_rvalue);
2266 gimple_push_condition ();
2268 gimplify_to_stmt_list (&TREE_OPERAND (expr, 1));
2269 gimplify_to_stmt_list (&TREE_OPERAND (expr, 2));
2270 recalculate_side_effects (expr);
2272 gimple_pop_condition (pre_p);
2274 if (ret == GS_ERROR)
2276 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2278 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 2)))
2279 /* Rewrite "if (a); else b" to "if (!a) b" */
2281 TREE_OPERAND (expr, 0) = invert_truthvalue (TREE_OPERAND (expr, 0));
2282 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2283 is_gimple_condexpr, fb_rvalue);
2285 tmp = TREE_OPERAND (expr, 1);
2286 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 2);
2287 TREE_OPERAND (expr, 2) = tmp;
2290 /* Both arms are empty; replace the COND_EXPR with its predicate. */
2291 expr = TREE_OPERAND (expr, 0);
2297 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2298 a call to __builtin_memcpy. */
2300 static enum gimplify_status
2301 gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value)
2303 tree args, t, to, to_ptr, from;
2305 to = TREE_OPERAND (*expr_p, 0);
2306 from = TREE_OPERAND (*expr_p, 1);
2308 args = tree_cons (NULL, size, NULL);
2310 t = build_fold_addr_expr (from);
2311 args = tree_cons (NULL, t, args);
2313 to_ptr = build_fold_addr_expr (to);
2314 args = tree_cons (NULL, to_ptr, args);
2315 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
2316 t = build_function_call_expr (t, args);
2320 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2321 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2328 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2329 a call to __builtin_memset. In this case we know that the RHS is
2330 a CONSTRUCTOR with an empty element list. */
2332 static enum gimplify_status
2333 gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value)
2335 tree args, t, to, to_ptr;
2337 to = TREE_OPERAND (*expr_p, 0);
2339 args = tree_cons (NULL, size, NULL);
2341 args = tree_cons (NULL, integer_zero_node, args);
2343 to_ptr = build_fold_addr_expr (to);
2344 args = tree_cons (NULL, to_ptr, args);
2345 t = implicit_built_in_decls[BUILT_IN_MEMSET];
2346 t = build_function_call_expr (t, args);
2350 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2351 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2358 /* A subroutine of gimplify_modify_expr. Break out elements of a
2359 CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.
2361 Note that we still need to clear any elements that don't have explicit
2362 initializers, so if not all elements are initialized we keep the
2363 original MODIFY_EXPR, we just remove all of the constructor elements. */
2365 static enum gimplify_status
2366 gimplify_init_constructor (tree *expr_p, tree *pre_p,
2367 tree *post_p, bool want_value)
2369 tree object = TREE_OPERAND (*expr_p, 0);
2370 tree ctor = TREE_OPERAND (*expr_p, 1);
2371 tree type = TREE_TYPE (ctor);
2372 enum gimplify_status ret;
2375 if (TREE_CODE (ctor) != CONSTRUCTOR)
2376 return GS_UNHANDLED;
2378 elt_list = CONSTRUCTOR_ELTS (ctor);
2381 switch (TREE_CODE (type))
2385 case QUAL_UNION_TYPE:
2388 HOST_WIDE_INT i, num_elements, num_nonzero_elements;
2389 HOST_WIDE_INT num_nonconstant_elements;
2392 /* Aggregate types must lower constructors to initialization of
2393 individual elements. The exception is that a CONSTRUCTOR node
2394 with no elements indicates zero-initialization of the whole. */
2395 if (elt_list == NULL)
2403 return GS_UNHANDLED;
2406 categorize_ctor_elements (ctor, &num_nonzero_elements,
2407 &num_nonconstant_elements);
2408 num_elements = count_type_elements (TREE_TYPE (ctor));
2410 /* If a const aggregate variable is being initialized, then it
2411 should never be a lose to promote the variable to be static. */
2412 if (num_nonconstant_elements == 0
2413 && TREE_READONLY (object)
2414 && TREE_CODE (object) == VAR_DECL)
2416 DECL_INITIAL (object) = ctor;
2417 TREE_STATIC (object) = 1;
2418 if (!DECL_NAME (object))
2419 DECL_NAME (object) = create_tmp_var_name ("C");
2420 walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL);
2422 /* ??? C++ doesn't automatically append a .<number> to the
2423 assembler name, and even when it does, it looks a FE private
2424 data structures to figure out what that number should be,
2425 which are not set for this variable. I suppose this is
2426 important for local statics for inline functions, which aren't
2427 "local" in the object file sense. So in order to get a unique
2428 TU-local symbol, we must invoke the lhd version now. */
2429 lhd_set_decl_assembler_name (object);
2431 *expr_p = NULL_TREE;
2435 /* If there are "lots" of initialized elements, and all of them
2436 are valid address constants, then the entire initializer can
2437 be dropped to memory, and then memcpy'd out. */
2438 if (num_nonconstant_elements == 0)
2440 HOST_WIDE_INT size = int_size_in_bytes (type);
2443 /* ??? We can still get unbounded array types, at least
2444 from the C++ front end. This seems wrong, but attempt
2445 to work around it for now. */
2448 size = int_size_in_bytes (TREE_TYPE (object));
2450 TREE_TYPE (ctor) = type = TREE_TYPE (object);
2453 /* Find the maximum alignment we can assume for the object. */
2454 /* ??? Make use of DECL_OFFSET_ALIGN. */
2455 if (DECL_P (object))
2456 align = DECL_ALIGN (object);
2458 align = TYPE_ALIGN (type);
2460 if (size > 0 && !can_move_by_pieces (size, align))
2462 tree new = create_tmp_var_raw (type, "C");
2463 gimple_add_tmp_var (new);
2464 TREE_STATIC (new) = 1;
2465 TREE_READONLY (new) = 1;
2466 DECL_INITIAL (new) = ctor;
2467 if (align > DECL_ALIGN (new))
2469 DECL_ALIGN (new) = align;
2470 DECL_USER_ALIGN (new) = 1;
2472 walk_tree (&DECL_INITIAL (new), force_labels_r, NULL, NULL);
2474 TREE_OPERAND (*expr_p, 1) = new;
2479 /* If there are "lots" of initialized elements, even discounting
2480 those that are not address constants (and thus *must* be
2481 computed at runtime), then partition the constructor into
2482 constant and non-constant parts. Block copy the constant
2483 parts in, then generate code for the non-constant parts. */
2484 /* TODO. There's code in cp/typeck.c to do this. */
2486 /* If there are "lots" of zeros, then block clear the object first. */
2488 if (num_elements - num_nonzero_elements > CLEAR_RATIO
2489 && num_nonzero_elements < num_elements/4)
2492 /* ??? This bit ought not be needed. For any element not present
2493 in the initializer, we should simply set them to zero. Except
2494 we'd need to *find* the elements that are not present, and that
2495 requires trickery to avoid quadratic compile-time behavior in
2496 large cases or excessive memory use in small cases. */
2499 HOST_WIDE_INT len = list_length (elt_list);
2500 if (TREE_CODE (type) == ARRAY_TYPE)
2502 tree nelts = array_type_nelts (type);
2503 if (!host_integerp (nelts, 1)
2504 || tree_low_cst (nelts, 1) + 1 != len)
2507 else if (len != fields_length (type))
2513 /* Zap the CONSTRUCTOR element list, which simplifies this case.
2514 Note that we still have to gimplify, in order to handle the
2515 case of variable sized types. Make an unshared copy of
2516 OBJECT before that so we can match a PLACEHOLDER_EXPR to it
2517 later, if needed. */
2518 CONSTRUCTOR_ELTS (ctor) = NULL_TREE;
2519 object = unshare_expr (TREE_OPERAND (*expr_p, 0));
2520 gimplify_stmt (expr_p);
2521 append_to_statement_list (*expr_p, pre_p);
2524 for (i = 0; elt_list; i++, elt_list = TREE_CHAIN (elt_list))
2526 tree purpose, value, cref, init;
2528 purpose = TREE_PURPOSE (elt_list);
2529 value = TREE_VALUE (elt_list);
2531 if (cleared && initializer_zerop (value))
2534 if (TREE_CODE (type) == ARRAY_TYPE)
2536 tree t = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object)));
2538 /* ??? Here's to hoping the front end fills in all of the
2539 indicies, so we don't have to figure out what's missing
2543 /* ??? Need to handle this. */
2544 if (TREE_CODE (purpose) == RANGE_EXPR)
2547 cref = build (ARRAY_REF, t, unshare_expr (object), purpose,
2548 NULL_TREE, NULL_TREE);
2551 cref = build (COMPONENT_REF, TREE_TYPE (purpose),
2552 unshare_expr (object), purpose, NULL_TREE);
2554 init = build (MODIFY_EXPR, TREE_TYPE (purpose), cref, value);
2556 /* Each member initialization is a full-expression. */
2557 gimplify_and_add (init, pre_p);
2560 *expr_p = NULL_TREE;
2568 /* Extract the real and imaginary parts out of the ctor. */
2572 r = TREE_VALUE (elt_list);
2573 elt_list = TREE_CHAIN (elt_list);
2576 i = TREE_VALUE (elt_list);
2577 if (TREE_CHAIN (elt_list))
2581 if (r == NULL || i == NULL)
2583 tree zero = convert (TREE_TYPE (type), integer_zero_node);
2590 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
2591 represent creation of a complex value. */
2592 if (TREE_CONSTANT (r) && TREE_CONSTANT (i))
2594 ctor = build_complex (type, r, i);
2595 TREE_OPERAND (*expr_p, 1) = ctor;
2599 ctor = build (COMPLEX_EXPR, type, r, i);
2600 TREE_OPERAND (*expr_p, 1) = ctor;
2601 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
2602 is_gimple_tmp_rhs, fb_rvalue);
2608 /* Go ahead and simplify constant constructors to VECTOR_CST. */
2609 if (TREE_CONSTANT (ctor))
2610 TREE_OPERAND (*expr_p, 1) = build_vector (type, elt_list);
2613 /* Vector types use CONSTRUCTOR all the way through gimple
2614 compilation as a general initializer. */
2615 for (; elt_list; elt_list = TREE_CHAIN (elt_list))
2617 enum gimplify_status tret;
2618 tret = gimplify_expr (&TREE_VALUE (elt_list), pre_p, post_p,
2619 is_gimple_constructor_elt, fb_rvalue);
2620 if (tret == GS_ERROR)
2627 /* So how did we get a CONSTRUCTOR for a scalar type? */
2631 if (ret == GS_ERROR)
2633 else if (want_value)
2635 append_to_statement_list (*expr_p, pre_p);
2643 /* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs
2644 based on the code of the RHS. We loop for as long as something changes. */
2646 static enum gimplify_status
2647 gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p,
2648 tree *post_p, bool want_value)
2650 enum gimplify_status ret = GS_OK;
2652 while (ret != GS_UNHANDLED)
2653 switch (TREE_CODE (*from_p))
2657 /* If we are initializing something from a TARGET_EXPR, strip the
2658 TARGET_EXPR and initialize it directly, if possible. This can't
2659 be done if the initializer is void, since that implies that the
2660 temporary is set in some non-trivial way.
2662 ??? What about code that pulls out the temp and uses it
2663 elsewhere? I think that such code never uses the TARGET_EXPR as
2664 an initializer. If I'm wrong, we'll abort because the temp won't
2665 have any RTL. In that case, I guess we'll need to replace
2666 references somehow. */
2667 tree init = TARGET_EXPR_INITIAL (*from_p);
2669 if (!VOID_TYPE_P (TREE_TYPE (init)))
2680 /* Remove any COMPOUND_EXPR in the RHS so the following cases will be
2682 gimplify_compound_expr (from_p, pre_p, true);
2687 /* If we're initializing from a CONSTRUCTOR, break this into
2688 individual MODIFY_EXPRs. */
2689 return gimplify_init_constructor (expr_p, pre_p, post_p, want_value);
2692 /* If we're assigning from a ?: expression with ADDRESSABLE type, push
2693 the assignment down into the branches, since we can't generate a
2694 temporary of such a type. */
2695 if (TREE_ADDRESSABLE (TREE_TYPE (*from_p)))
2698 return gimplify_cond_expr (expr_p, pre_p, *to_p);
2712 /* Gimplify the MODIFY_EXPR node pointed by EXPR_P.
2718 PRE_P points to the list where side effects that must happen before
2719 *EXPR_P should be stored.
2721 POST_P points to the list where side effects that must happen after
2722 *EXPR_P should be stored.
2724 WANT_VALUE is nonzero iff we want to use the value of this expression
2725 in another expression. */
2727 static enum gimplify_status
2728 gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value)
2730 tree *from_p = &TREE_OPERAND (*expr_p, 1);
2731 tree *to_p = &TREE_OPERAND (*expr_p, 0);
2732 enum gimplify_status ret = GS_UNHANDLED;
2734 #if defined ENABLE_CHECKING
2735 if (TREE_CODE (*expr_p) != MODIFY_EXPR && TREE_CODE (*expr_p) != INIT_EXPR)
2739 /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer useful. */
2740 if (TREE_CODE (*expr_p) == INIT_EXPR)
2741 TREE_SET_CODE (*expr_p, MODIFY_EXPR);
2743 /* See if any simplifications can be done based on what the RHS is. */
2744 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2746 if (ret != GS_UNHANDLED)
2749 /* If the value being copied is of variable width, compute the length
2750 of the copy into a WITH_SIZE_EXPR. Note that we need to do this
2751 before gimplifying any of the operands so that we can resolve any
2752 PLACEHOLDER_EXPRs in the size. Also note that the RTL expander uses
2753 the size of the expression to be copied, not of the destination, so
2754 that is what we must here. */
2755 maybe_with_size_expr (from_p);
2757 ret = gimplify_expr (to_p, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
2758 if (ret == GS_ERROR)
2761 ret = gimplify_expr (from_p, pre_p, post_p,
2762 rhs_predicate_for (*to_p), fb_rvalue);
2763 if (ret == GS_ERROR)
2766 /* Now see if the above changed *from_p to something we handle specially. */
2767 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2769 if (ret != GS_UNHANDLED)
2772 /* If we've got a variable sized assignment between two lvalues (i.e. does
2773 not involve a call), then we can make things a bit more straightforward
2774 by converting the assignment to memcpy or memset. */
2775 if (TREE_CODE (*from_p) == WITH_SIZE_EXPR)
2777 tree from = TREE_OPERAND (*from_p, 0);
2778 tree size = TREE_OPERAND (*from_p, 1);
2780 if (TREE_CODE (from) == CONSTRUCTOR)
2781 return gimplify_modify_expr_to_memset (expr_p, size, want_value);
2782 if (is_gimple_addr_expr_arg (from))
2785 return gimplify_modify_expr_to_memcpy (expr_p, size, want_value);
2789 /* If the destination is already simple, nothing else needed. */
2790 if (is_gimple_tmp_var (*to_p) || !want_value)
2797 append_to_statement_list (*expr_p, pre_p);
2804 /* Gimplify a comparison between two variable-sized objects. Do this
2805 with a call to BUILT_IN_MEMCMP. */
2807 static enum gimplify_status
2808 gimplify_variable_sized_compare (tree *expr_p)
2810 tree op0 = TREE_OPERAND (*expr_p, 0);
2811 tree op1 = TREE_OPERAND (*expr_p, 1);
2814 t = TYPE_SIZE_UNIT (TREE_TYPE (op0));
2815 t = unshare_expr (t);
2816 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, op0);
2817 args = tree_cons (NULL, t, NULL);
2818 t = build_fold_addr_expr (op1);
2819 args = tree_cons (NULL, t, args);
2820 dest = build_fold_addr_expr (op0);
2821 args = tree_cons (NULL, dest, args);
2822 t = implicit_built_in_decls[BUILT_IN_MEMCMP];
2823 t = build_function_call_expr (t, args);
2825 = build (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), t, integer_zero_node);
2830 /* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P
2831 points to the expression to gimplify.
2833 Expressions of the form 'a && b' are gimplified to:
2835 a && b ? true : false
2837 gimplify_cond_expr will do the rest.
2839 PRE_P points to the list where side effects that must happen before
2840 *EXPR_P should be stored. */
2842 static enum gimplify_status
2843 gimplify_boolean_expr (tree *expr_p)
2845 /* Preserve the original type of the expression. */
2846 tree type = TREE_TYPE (*expr_p);
2848 *expr_p = build (COND_EXPR, type, *expr_p,
2849 convert (type, boolean_true_node),
2850 convert (type, boolean_false_node));
2855 /* Gimplifies an expression sequence. This function gimplifies each
2856 expression and re-writes the original expression with the last
2857 expression of the sequence in GIMPLE form.
2859 PRE_P points to the list where the side effects for all the
2860 expressions in the sequence will be emitted.
2862 WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */
2863 /* ??? Should rearrange to share the pre-queue with all the indirect
2864 invocations of gimplify_expr. Would probably save on creations
2865 of statement_list nodes. */
2867 static enum gimplify_status
2868 gimplify_compound_expr (tree *expr_p, tree *pre_p, bool want_value)
2874 tree *sub_p = &TREE_OPERAND (t, 0);
2876 if (TREE_CODE (*sub_p) == COMPOUND_EXPR)
2877 gimplify_compound_expr (sub_p, pre_p, false);
2879 gimplify_stmt (sub_p);
2880 append_to_statement_list (*sub_p, pre_p);
2882 t = TREE_OPERAND (t, 1);
2884 while (TREE_CODE (t) == COMPOUND_EXPR);
2891 gimplify_stmt (expr_p);
2896 /* Gimplifies a statement list. These may be created either by an
2897 enlightened front-end, or by shortcut_cond_expr. */
2899 static enum gimplify_status
2900 gimplify_statement_list (tree *expr_p)
2902 tree_stmt_iterator i = tsi_start (*expr_p);
2904 while (!tsi_end_p (i))
2908 gimplify_stmt (tsi_stmt_ptr (i));
2913 else if (TREE_CODE (t) == STATEMENT_LIST)
2915 tsi_link_before (&i, t, TSI_SAME_STMT);
2925 /* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to
2926 gimplify. After gimplification, EXPR_P will point to a new temporary
2927 that holds the original value of the SAVE_EXPR node.
2929 PRE_P points to the list where side effects that must happen before
2930 *EXPR_P should be stored. */
2932 static enum gimplify_status
2933 gimplify_save_expr (tree *expr_p, tree *pre_p, tree *post_p)
2935 enum gimplify_status ret = GS_ALL_DONE;
2938 #if defined ENABLE_CHECKING
2939 if (TREE_CODE (*expr_p) != SAVE_EXPR)
2943 val = TREE_OPERAND (*expr_p, 0);
2945 /* If the operand is already a GIMPLE temporary, just re-write the
2947 if (is_gimple_tmp_var (val))
2949 /* The operand may be a void-valued expression such as SAVE_EXPRs
2950 generated by the Java frontend for class initialization. It is
2951 being executed only for its side-effects. */
2952 else if (TREE_TYPE (val) == void_type_node)
2954 tree body = TREE_OPERAND (*expr_p, 0);
2955 ret = gimplify_expr (& body, pre_p, post_p, is_gimple_stmt, fb_none);
2956 append_to_statement_list (body, pre_p);
2960 *expr_p = TREE_OPERAND (*expr_p, 0)
2961 = get_initialized_tmp_var (val, pre_p, post_p);
2966 /* Re-write the ADDR_EXPR node pointed by EXPR_P
2973 PRE_P points to the list where side effects that must happen before
2974 *EXPR_P should be stored.
2976 POST_P points to the list where side effects that must happen after
2977 *EXPR_P should be stored. */
2979 static enum gimplify_status
2980 gimplify_addr_expr (tree *expr_p, tree *pre_p, tree *post_p)
2982 tree expr = *expr_p;
2983 tree op0 = TREE_OPERAND (expr, 0);
2984 enum gimplify_status ret;
2986 switch (TREE_CODE (op0))
2989 /* Check if we are dealing with an expression of the form '&*ptr'.
2990 While the front end folds away '&*ptr' into 'ptr', these
2991 expressions may be generated internally by the compiler (e.g.,
2992 builtins like __builtin_va_end). */
2993 *expr_p = TREE_OPERAND (op0, 0);
2998 /* Fold &a[6] to (&a + 6). */
2999 ret = gimplify_array_ref_to_plus (&TREE_OPERAND (expr, 0),
3002 /* This added an INDIRECT_REF. Fold it away. */
3003 *expr_p = TREE_OPERAND (TREE_OPERAND (expr, 0), 0);
3006 case VIEW_CONVERT_EXPR:
3007 /* Take the address of our operand and then convert it to the type of
3010 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3011 all clear. The impact of this transformation is even less clear. */
3012 *expr_p = fold_convert (TREE_TYPE (expr),
3013 build_fold_addr_expr (TREE_OPERAND (op0, 0)));
3018 /* We use fb_either here because the C frontend sometimes takes
3019 the address of a call that returns a struct. */
3020 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, post_p,
3021 is_gimple_addr_expr_arg, fb_either);
3022 if (ret != GS_ERROR)
3024 /* Make sure TREE_INVARIANT, TREE_CONSTANT, and TREE_SIDE_EFFECTS
3026 recompute_tree_invarant_for_addr_expr (expr);
3028 /* Mark the RHS addressable. */
3029 lang_hooks.mark_addressable (TREE_OPERAND (expr, 0));
3034 /* If the operand is gimplified into a _DECL, mark the address expression
3035 as TREE_INVARIANT. */
3036 if (DECL_P (TREE_OPERAND (expr, 0)))
3037 TREE_INVARIANT (expr) = 1;
3042 /* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple
3043 value; output operands should be a gimple lvalue. */
3045 static enum gimplify_status
3046 gimplify_asm_expr (tree *expr_p, tree *pre_p, tree *post_p)
3048 tree expr = *expr_p;
3049 int noutputs = list_length (ASM_OUTPUTS (expr));
3050 const char **oconstraints
3051 = (const char **) alloca ((noutputs) * sizeof (const char *));
3054 const char *constraint;
3055 bool allows_mem, allows_reg, is_inout;
3056 enum gimplify_status ret, tret;
3059 = resolve_asm_operand_names (ASM_STRING (expr), ASM_OUTPUTS (expr),
3063 for (i = 0, link = ASM_OUTPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3065 oconstraints[i] = constraint
3066 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3068 parse_output_constraint (&constraint, i, 0, 0,
3069 &allows_mem, &allows_reg, &is_inout);
3071 if (!allows_reg && allows_mem)
3072 lang_hooks.mark_addressable (TREE_VALUE (link));
3074 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3075 is_inout ? is_gimple_min_lval : is_gimple_lvalue,
3076 fb_lvalue | fb_mayfail);
3077 if (tret == GS_ERROR)
3079 error ("invalid lvalue in asm output %d", i);
3085 /* An input/output operand. To give the optimizers more
3086 flexibility, split it into separate input and output
3090 size_t constraint_len = strlen (constraint);
3092 /* Turn the in/out constraint into an output constraint. */
3093 char *p = xstrdup (constraint);
3095 TREE_VALUE (TREE_PURPOSE (link)) = build_string (constraint_len, p);
3098 /* And add a matching input constraint. */
3101 sprintf (buf, "%d", i);
3102 input = build_string (strlen (buf), buf);
3105 input = build_string (constraint_len - 1, constraint + 1);
3106 input = build_tree_list (build_tree_list (NULL_TREE, input),
3107 unshare_expr (TREE_VALUE (link)));
3108 ASM_INPUTS (expr) = chainon (ASM_INPUTS (expr), input);
3112 for (link = ASM_INPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3115 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3116 parse_input_constraint (&constraint, 0, 0, noutputs, 0,
3117 oconstraints, &allows_mem, &allows_reg);
3119 /* If the operand is a memory input, it should be an lvalue. */
3120 if (!allows_reg && allows_mem)
3122 lang_hooks.mark_addressable (TREE_VALUE (link));
3123 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3124 is_gimple_lvalue, fb_lvalue | fb_mayfail);
3125 if (tret == GS_ERROR)
3127 error ("memory input %d is not directly addressable", i);
3133 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3134 is_gimple_val, fb_rvalue);
3135 if (tret == GS_ERROR)
3143 /* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding
3144 WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
3145 gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
3146 return to this function.
3148 FIXME should we complexify the prequeue handling instead? Or use flags
3149 for all the cleanups and let the optimizer tighten them up? The current
3150 code seems pretty fragile; it will break on a cleanup within any
3151 non-conditional nesting. But any such nesting would be broken, anyway;
3152 we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
3153 and continues out of it. We can do that at the RTL level, though, so
3154 having an optimizer to tighten up try/finally regions would be a Good
3157 static enum gimplify_status
3158 gimplify_cleanup_point_expr (tree *expr_p, tree *pre_p)
3160 tree_stmt_iterator iter;
3163 tree temp = voidify_wrapper_expr (*expr_p, NULL);
3165 /* We only care about the number of conditions between the innermost
3166 CLEANUP_POINT_EXPR and the cleanup. So save and reset the count. */
3167 int old_conds = gimplify_ctxp->conditions;
3168 gimplify_ctxp->conditions = 0;
3170 body = TREE_OPERAND (*expr_p, 0);
3171 gimplify_to_stmt_list (&body);
3173 gimplify_ctxp->conditions = old_conds;
3175 for (iter = tsi_start (body); !tsi_end_p (iter); )
3177 tree *wce_p = tsi_stmt_ptr (iter);
3180 if (TREE_CODE (wce) == WITH_CLEANUP_EXPR)
3182 if (tsi_one_before_end_p (iter))
3184 tsi_link_before (&iter, TREE_OPERAND (wce, 0), TSI_SAME_STMT);
3192 sl = tsi_split_statement_list_after (&iter);
3193 tfe = build (TRY_FINALLY_EXPR, void_type_node, sl, NULL_TREE);
3194 append_to_statement_list (TREE_OPERAND (wce, 0),
3195 &TREE_OPERAND (tfe, 1));
3197 iter = tsi_start (sl);
3207 append_to_statement_list (body, pre_p);
3217 /* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP
3218 is the cleanup action required. */
3221 gimple_push_cleanup (tree var, tree cleanup, tree *pre_p)
3225 /* Errors can result in improperly nested cleanups. Which results in
3226 confusion when trying to resolve the WITH_CLEANUP_EXPR. */
3227 if (errorcount || sorrycount)
3230 if (gimple_conditional_context ())
3232 /* If we're in a conditional context, this is more complex. We only
3233 want to run the cleanup if we actually ran the initialization that
3234 necessitates it, but we want to run it after the end of the
3235 conditional context. So we wrap the try/finally around the
3236 condition and use a flag to determine whether or not to actually
3237 run the destructor. Thus
3241 becomes (approximately)
3245 if (test) { A::A(temp); flag = 1; val = f(temp); }
3248 if (flag) A::~A(temp);
3253 tree flag = create_tmp_var (boolean_type_node, "cleanup");
3254 tree ffalse = build (MODIFY_EXPR, void_type_node, flag,
3255 boolean_false_node);
3256 tree ftrue = build (MODIFY_EXPR, void_type_node, flag,
3258 cleanup = build (COND_EXPR, void_type_node, flag, cleanup, NULL);
3259 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3260 append_to_statement_list (ffalse, &gimplify_ctxp->conditional_cleanups);
3261 append_to_statement_list (wce, &gimplify_ctxp->conditional_cleanups);
3262 append_to_statement_list (ftrue, pre_p);
3264 /* Because of this manipulation, and the EH edges that jump
3265 threading cannot redirect, the temporary (VAR) will appear
3266 to be used uninitialized. Don't warn. */
3267 TREE_NO_WARNING (var) = 1;
3271 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3272 append_to_statement_list (wce, pre_p);
3275 gimplify_stmt (&TREE_OPERAND (wce, 0));
3278 /* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */
3280 static enum gimplify_status
3281 gimplify_target_expr (tree *expr_p, tree *pre_p, tree *post_p)
3283 tree targ = *expr_p;
3284 tree temp = TARGET_EXPR_SLOT (targ);
3285 tree init = TARGET_EXPR_INITIAL (targ);
3286 enum gimplify_status ret;
3290 /* TARGET_EXPR temps aren't part of the enclosing block, so add it
3291 to the temps list. */
3292 gimple_add_tmp_var (temp);
3294 /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
3295 expression is supposed to initialize the slot. */
3296 if (VOID_TYPE_P (TREE_TYPE (init)))
3297 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, fb_none);
3300 /* Special handling for BIND_EXPR can result in fewer temps. */
3302 if (TREE_CODE (init) == BIND_EXPR)
3303 gimplify_bind_expr (&init, temp, pre_p);
3306 init = build (MODIFY_EXPR, void_type_node, temp, init);
3307 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt,
3311 if (ret == GS_ERROR)
3313 append_to_statement_list (init, pre_p);
3315 /* If needed, push the cleanup for the temp. */
3316 if (TARGET_EXPR_CLEANUP (targ))
3318 gimplify_stmt (&TARGET_EXPR_CLEANUP (targ));
3319 gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ), pre_p);
3322 /* Only expand this once. */
3323 TREE_OPERAND (targ, 3) = init;
3324 TARGET_EXPR_INITIAL (targ) = NULL_TREE;
3326 else if (!DECL_SEEN_IN_BIND_EXPR_P (temp))
3327 /* We should have expanded this before. */
3334 /* Gimplification of expression trees. */
3336 /* Gimplify an expression which appears at statement context; usually, this
3337 means replacing it with a suitably gimple STATEMENT_LIST. */
3340 gimplify_stmt (tree *stmt_p)
3342 gimplify_expr (stmt_p, NULL, NULL, is_gimple_stmt, fb_none);
3345 /* Similarly, but force the result to be a STATEMENT_LIST. */
3348 gimplify_to_stmt_list (tree *stmt_p)
3350 gimplify_stmt (stmt_p);
3352 *stmt_p = alloc_stmt_list ();
3353 else if (TREE_CODE (*stmt_p) != STATEMENT_LIST)
3356 *stmt_p = alloc_stmt_list ();
3357 append_to_statement_list (t, stmt_p);
3362 /* Gimplifies the expression tree pointed by EXPR_P. Return 0 if
3363 gimplification failed.
3365 PRE_P points to the list where side effects that must happen before
3366 EXPR should be stored.
3368 POST_P points to the list where side effects that must happen after
3369 EXPR should be stored, or NULL if there is no suitable list. In
3370 that case, we copy the result to a temporary, emit the
3371 post-effects, and then return the temporary.
3373 GIMPLE_TEST_F points to a function that takes a tree T and
3374 returns nonzero if T is in the GIMPLE form requested by the
3375 caller. The GIMPLE predicates are in tree-gimple.c.
3377 This test is used twice. Before gimplification, the test is
3378 invoked to determine whether *EXPR_P is already gimple enough. If
3379 that fails, *EXPR_P is gimplified according to its code and
3380 GIMPLE_TEST_F is called again. If the test still fails, then a new
3381 temporary variable is created and assigned the value of the
3382 gimplified expression.
3384 FALLBACK tells the function what sort of a temporary we want. If the 1
3385 bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK.
3386 If both are set, either is OK, but an lvalue is preferable.
3388 The return value is either GS_ERROR or GS_ALL_DONE, since this function
3389 iterates until solution. */
3391 enum gimplify_status
3392 gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
3393 bool (* gimple_test_f) (tree), fallback_t fallback)
3396 tree internal_pre = NULL_TREE;
3397 tree internal_post = NULL_TREE;
3399 int is_statement = (pre_p == NULL);
3400 location_t saved_location;
3401 enum gimplify_status ret;
3403 save_expr = *expr_p;
3404 if (save_expr == NULL_TREE)
3407 /* We used to check the predicate here and return immediately if it
3408 succeeds. This is wrong; the design is for gimplification to be
3409 idempotent, and for the predicates to only test for valid forms, not
3410 whether they are fully simplified. */
3412 /* Set up our internal queues if needed. */
3414 pre_p = &internal_pre;
3416 post_p = &internal_post;
3418 saved_location = input_location;
3419 if (save_expr != error_mark_node
3420 && EXPR_HAS_LOCATION (*expr_p))
3421 input_location = EXPR_LOCATION (*expr_p);
3423 /* Loop over the specific gimplifiers until the toplevel node
3424 remains the same. */
3427 /* Strip away as many useless type conversions as possible
3429 STRIP_USELESS_TYPE_CONVERSION (*expr_p);
3431 /* Remember the expr. */
3432 save_expr = *expr_p;
3434 /* Die, die, die, my darling. */
3435 if (save_expr == error_mark_node
3436 || (TREE_TYPE (save_expr)
3437 && TREE_TYPE (save_expr) == error_mark_node))
3443 /* Do any language-specific gimplification. */
3444 ret = lang_hooks.gimplify_expr (expr_p, pre_p, post_p);
3447 if (*expr_p == NULL_TREE)
3449 if (*expr_p != save_expr)
3452 else if (ret != GS_UNHANDLED)
3456 switch (TREE_CODE (*expr_p))
3458 /* First deal with the special cases. */
3460 case POSTINCREMENT_EXPR:
3461 case POSTDECREMENT_EXPR:
3462 case PREINCREMENT_EXPR:
3463 case PREDECREMENT_EXPR:
3464 ret = gimplify_self_mod_expr (expr_p, pre_p, post_p,
3465 fallback != fb_none);
3469 case ARRAY_RANGE_REF:
3473 ret = gimplify_compound_lval (expr_p, pre_p, post_p,
3474 fallback ? fallback : fb_rvalue);
3478 ret = gimplify_cond_expr (expr_p, pre_p, NULL_TREE);
3482 ret = gimplify_call_expr (expr_p, pre_p, fallback != fb_none);
3489 ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none);
3494 ret = gimplify_modify_expr (expr_p, pre_p, post_p,
3495 fallback != fb_none);
3498 case TRUTH_ANDIF_EXPR:
3499 case TRUTH_ORIF_EXPR:
3500 ret = gimplify_boolean_expr (expr_p);
3503 case TRUTH_NOT_EXPR:
3504 TREE_OPERAND (*expr_p, 0)
3505 = gimple_boolify (TREE_OPERAND (*expr_p, 0));
3506 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3507 is_gimple_val, fb_rvalue);
3508 recalculate_side_effects (*expr_p);
3512 ret = gimplify_addr_expr (expr_p, pre_p, post_p);
3516 ret = gimplify_va_arg_expr (expr_p, pre_p, post_p);
3519 case VIEW_CONVERT_EXPR:
3520 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
3521 || fallback == fb_none)
3523 /* Just strip a conversion to void (or in void context) and
3525 *expr_p = TREE_OPERAND (*expr_p, 0);
3529 /* If both types are BLKmode or if one type is of variable size,
3530 convert this into a pointer punning operation. This avoids
3531 copies of large data or making a variable-size temporary.
3533 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3534 all clear. The impact of this transformation is even less
3537 if ((TYPE_MODE (TREE_TYPE (*expr_p)) == BLKmode
3538 && TYPE_MODE (TREE_TYPE (TREE_OPERAND (*expr_p, 0))) == BLKmode)
3539 || !TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (*expr_p)))
3540 || !TREE_CONSTANT (TYPE_SIZE (TREE_TYPE
3541 (TREE_OPERAND (*expr_p,0)))))
3543 tree restype = TREE_TYPE (*expr_p);
3544 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (*expr_p),
3545 fold_convert (build_pointer_type (restype),
3546 build_fold_addr_expr
3547 (TREE_OPERAND (*expr_p, 0))));
3554 if (IS_EMPTY_STMT (*expr_p))
3560 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
3561 || fallback == fb_none)
3563 /* Just strip a conversion to void (or in void context) and
3565 *expr_p = TREE_OPERAND (*expr_p, 0);
3569 ret = gimplify_conversion (expr_p);
3570 if (ret == GS_ERROR)
3572 if (*expr_p != save_expr)
3576 case FIX_TRUNC_EXPR:
3578 case FIX_FLOOR_EXPR:
3579 case FIX_ROUND_EXPR:
3581 /* unary_expr: ... | '(' cast ')' val | ... */
3582 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3583 is_gimple_val, fb_rvalue);
3584 recalculate_side_effects (*expr_p);
3588 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3589 is_gimple_reg, fb_rvalue);
3590 recalculate_side_effects (*expr_p);
3593 /* Constants need not be gimplified. */
3603 *expr_p = DECL_INITIAL (*expr_p);
3607 ret = gimplify_decl_expr (expr_p);
3611 /* FIXME make this a decl. */
3616 ret = gimplify_bind_expr (expr_p, NULL, pre_p);
3620 ret = gimplify_loop_expr (expr_p, pre_p);
3624 ret = gimplify_switch_expr (expr_p, pre_p);
3627 case LABELED_BLOCK_EXPR:
3628 ret = gimplify_labeled_block_expr (expr_p);
3631 case EXIT_BLOCK_EXPR:
3632 ret = gimplify_exit_block_expr (expr_p);
3636 ret = gimplify_exit_expr (expr_p);
3640 /* If the target is not LABEL, then it is a computed jump
3641 and the target needs to be gimplified. */
3642 if (TREE_CODE (GOTO_DESTINATION (*expr_p)) != LABEL_DECL)
3643 ret = gimplify_expr (&GOTO_DESTINATION (*expr_p), pre_p,
3644 NULL, is_gimple_val, fb_rvalue);
3649 #ifdef ENABLE_CHECKING
3650 if (decl_function_context (LABEL_EXPR_LABEL (*expr_p)) != current_function_decl)
3655 case CASE_LABEL_EXPR:
3656 ret = gimplify_case_label_expr (expr_p);
3660 ret = gimplify_return_expr (*expr_p, pre_p);
3664 /* Don't reduce this in place; let gimplify_init_constructor work its
3665 magic. Buf if we're just elaborating this for side effects, just
3666 gimplify any element that has side-effects. */
3667 if (fallback == fb_none)
3669 for (tmp = CONSTRUCTOR_ELTS (*expr_p); tmp;
3670 tmp = TREE_CHAIN (tmp))
3671 if (TREE_SIDE_EFFECTS (TREE_VALUE (tmp)))
3672 gimplify_expr (&TREE_VALUE (tmp), pre_p, post_p,
3673 gimple_test_f, fallback);
3675 *expr_p = NULL_TREE;
3681 /* The following are special cases that are not handled by the
3682 original GIMPLE grammar. */
3684 /* SAVE_EXPR nodes are converted into a GIMPLE identifier and
3687 ret = gimplify_save_expr (expr_p, pre_p, post_p);
3692 enum gimplify_status r0, r1, r2;
3694 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3695 is_gimple_lvalue, fb_either);
3696 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3697 is_gimple_val, fb_rvalue);
3698 r2 = gimplify_expr (&TREE_OPERAND (*expr_p, 2), pre_p, post_p,
3699 is_gimple_val, fb_rvalue);
3700 recalculate_side_effects (*expr_p);
3702 ret = MIN (r0, MIN (r1, r2));
3706 case NON_LVALUE_EXPR:
3707 /* This should have been stripped above. */
3712 ret = gimplify_asm_expr (expr_p, pre_p, post_p);
3715 case TRY_FINALLY_EXPR:
3716 case TRY_CATCH_EXPR:
3717 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 0));
3718 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 1));
3722 case CLEANUP_POINT_EXPR:
3723 ret = gimplify_cleanup_point_expr (expr_p, pre_p);
3727 ret = gimplify_target_expr (expr_p, pre_p, post_p);
3731 gimplify_to_stmt_list (&CATCH_BODY (*expr_p));
3735 case EH_FILTER_EXPR:
3736 gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p));
3742 enum gimplify_status r0, r1;
3743 r0 = gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p), pre_p, post_p,
3744 is_gimple_val, fb_rvalue);
3745 r1 = gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p), pre_p, post_p,
3746 is_gimple_val, fb_rvalue);
3753 ret = gimplify_minimax_expr (expr_p, pre_p, post_p);
3757 /* We get here when taking the address of a label. We mark
3758 the label as "forced"; meaning it can never be removed and
3759 it is a potential target for any computed goto. */
3760 FORCED_LABEL (*expr_p) = 1;
3764 case STATEMENT_LIST:
3765 ret = gimplify_statement_list (expr_p);
3768 case WITH_SIZE_EXPR:
3770 enum gimplify_status r0, r1;
3771 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3772 post_p == &internal_post ? NULL : post_p,
3773 gimple_test_f, fallback);
3774 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3775 is_gimple_val, fb_rvalue);
3780 /* ??? If this is a local variable, and it has not been seen in any
3781 outer BIND_EXPR, then it's probably the result of a duplicate
3782 declaration, for which we've already issued an error. It would
3783 be really nice if the front end wouldn't leak these at all.
3784 Currently the only known culprit is C++ destructors, as seen
3785 in g++.old-deja/g++.jason/binding.C. */
3787 if (!TREE_STATIC (tmp) && !DECL_EXTERNAL (tmp)
3788 && decl_function_context (tmp) == current_function_decl
3789 && !DECL_SEEN_IN_BIND_EXPR_P (tmp))
3791 #ifdef ENABLE_CHECKING
3792 if (!errorcount && !sorrycount)
3802 /* Allow callbacks into the gimplifier during optimization. */
3807 /* If this is a comparison of objects of aggregate type, handle
3808 it specially (by converting to a call to memcmp). It would be
3809 nice to only have to do this for variable-sized objects, but
3810 then we'd have to allow the same nest of reference nodes we
3811 allow for MODIFY_EXPR and that's too complex. */
3812 if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3813 && (AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 1)))))
3814 ret = gimplify_variable_sized_compare (expr_p);
3816 /* If *EXPR_P does not need to be special-cased, handle it
3817 according to its class. */
3818 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '1')
3819 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3820 post_p, is_gimple_val, fb_rvalue);
3821 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '2'
3822 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3823 || TREE_CODE (*expr_p) == TRUTH_AND_EXPR
3824 || TREE_CODE (*expr_p) == TRUTH_OR_EXPR
3825 || TREE_CODE (*expr_p) == TRUTH_XOR_EXPR)
3827 enum gimplify_status r0, r1;
3829 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3830 post_p, is_gimple_val, fb_rvalue);
3831 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p,
3832 post_p, is_gimple_val, fb_rvalue);
3836 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'd'
3837 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'c')
3843 /* Fail if we don't know how to handle this tree code. */
3846 recalculate_side_effects (*expr_p);
3850 /* If we replaced *expr_p, gimplify again. */
3851 if (ret == GS_OK && (*expr_p == NULL || *expr_p == save_expr))
3854 while (ret == GS_OK);
3856 /* If we encountered an error_mark somewhere nested inside, either
3857 stub out the statement or propagate the error back out. */
3858 if (ret == GS_ERROR)
3865 #ifdef ENABLE_CHECKING
3866 /* This was only valid as a return value from the langhook, which
3867 we handled. Make sure it doesn't escape from any other context. */
3868 if (ret == GS_UNHANDLED)
3872 if (fallback == fb_none && *expr_p && !is_gimple_stmt (*expr_p))
3874 /* We aren't looking for a value, and we don't have a valid
3875 statement. If it doesn't have side-effects, throw it away. */
3876 if (!TREE_SIDE_EFFECTS (*expr_p))
3878 else if (!TREE_THIS_VOLATILE (*expr_p))
3880 /* This is probably a _REF that contains something nested that
3881 has side effects. Recurse through the operands to find it. */
3882 enum tree_code code = TREE_CODE (*expr_p);
3884 if (code == COMPONENT_REF
3885 || code == REALPART_EXPR || code == IMAGPART_EXPR)
3886 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3887 gimple_test_f, fallback);
3888 else if (code == ARRAY_REF || code == ARRAY_RANGE_REF)
3890 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3891 gimple_test_f, fallback);
3892 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3893 gimple_test_f, fallback);
3896 /* Anything else with side-effects
3897 must be converted to a valid statement before we get here. */
3902 else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p)))
3904 /* Historically, the compiler has treated a bare
3905 reference to a volatile lvalue as forcing a load. */
3906 tree tmp = create_tmp_var (TREE_TYPE (*expr_p), "vol");
3907 *expr_p = build (MODIFY_EXPR, TREE_TYPE (tmp), tmp, *expr_p);
3910 /* We can't do anything useful with a volatile reference to
3911 incomplete type, so just throw it away. */
3915 /* If we are gimplifying at the statement level, we're done. Tack
3916 everything together and replace the original statement with the
3918 if (fallback == fb_none || is_statement)
3920 if (internal_pre || internal_post)
3922 append_to_statement_list (*expr_p, &internal_pre);
3923 append_to_statement_list (internal_post, &internal_pre);
3924 annotate_all_with_locus (&internal_pre, input_location);
3925 *expr_p = internal_pre;
3929 else if (TREE_CODE (*expr_p) == STATEMENT_LIST)
3930 annotate_all_with_locus (expr_p, input_location);
3932 annotate_one_with_locus (*expr_p, input_location);
3936 /* Otherwise we're gimplifying a subexpression, so the resulting value is
3939 /* If it's sufficiently simple already, we're done. Unless we are
3940 handling some post-effects internally; if that's the case, we need to
3941 copy into a temp before adding the post-effects to the tree. */
3942 if (!internal_post && (*gimple_test_f) (*expr_p))
3945 /* Otherwise, we need to create a new temporary for the gimplified
3948 /* We can't return an lvalue if we have an internal postqueue. The
3949 object the lvalue refers to would (probably) be modified by the
3950 postqueue; we need to copy the value out first, which means an
3952 if ((fallback & fb_lvalue) && !internal_post
3953 && is_gimple_addr_expr_arg (*expr_p))
3955 /* An lvalue will do. Take the address of the expression, store it
3956 in a temporary, and replace the expression with an INDIRECT_REF of
3958 tmp = build_fold_addr_expr (*expr_p);
3959 gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue);
3960 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp);
3962 else if ((fallback & fb_rvalue) && is_gimple_tmp_rhs (*expr_p))
3964 #if defined ENABLE_CHECKING
3965 if (VOID_TYPE_P (TREE_TYPE (*expr_p)))
3969 /* An rvalue will do. Assign the gimplified expression into a new
3970 temporary TMP and replace the original expression with TMP. */
3972 if (internal_post || (fallback & fb_lvalue))
3973 /* The postqueue might change the value of the expression between
3974 the initialization and use of the temporary, so we can't use a
3975 formal temp. FIXME do we care? */
3976 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
3978 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
3980 else if (fallback & fb_mayfail)
3982 /* If this is an asm statement, and the user asked for the impossible,
3983 don't abort. Fail and let gimplify_asm_expr issue an error. */
3989 fprintf (stderr, "gimplification failed:\n");
3990 print_generic_expr (stderr, *expr_p, 0);
3991 debug_tree (*expr_p);
3995 #if defined ENABLE_CHECKING
3996 /* Make sure the temporary matches our predicate. */
3997 if (!(*gimple_test_f) (*expr_p))
4003 annotate_all_with_locus (&internal_post, input_location);
4004 append_to_statement_list (internal_post, pre_p);
4008 input_location = saved_location;
4012 /* Look through TYPE for variable-sized objects and gimplify each such
4013 size that we find. Add to LIST_P any statements generated. */
4016 gimplify_type_sizes (tree type, tree *list_p)
4020 switch (TREE_CODE (type))
4030 gimplify_one_sizepos (&TYPE_MIN_VALUE (type), list_p);
4031 gimplify_one_sizepos (&TYPE_MAX_VALUE (type), list_p);
4035 /* These anonymous types don't have declarations, so handle them here. */
4036 gimplify_type_sizes (TYPE_DOMAIN (type), list_p);
4041 case QUAL_UNION_TYPE:
4042 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4043 if (TREE_CODE (field) == FIELD_DECL)
4044 gimplify_one_sizepos (&DECL_FIELD_OFFSET (field), list_p);
4051 gimplify_one_sizepos (&TYPE_SIZE (type), list_p);
4052 gimplify_one_sizepos (&TYPE_SIZE_UNIT (type), list_p);
4055 /* Subroutine of the above to gimplify one size or position, *EXPR_P.
4056 We add any required statements to STMT_P. */
4059 gimplify_one_sizepos (tree *expr_p, tree *stmt_p)
4061 /* We don't do anything if the value isn't there, is constant, or contains
4062 A PLACEHOLDER_EXPR. We also don't want to do anything if it's already
4063 a VAR_DECL. If it's a VAR_DECL from another function, the gimplfier
4064 will want to replace it with a new variable, but that will cause problems
4065 if this type is from outside the function. It's OK to have that here. */
4066 if (*expr_p == NULL_TREE || TREE_CONSTANT (*expr_p)
4067 || TREE_CODE (*expr_p) == VAR_DECL
4068 || CONTAINS_PLACEHOLDER_P (*expr_p))
4071 gimplify_expr (expr_p, stmt_p, NULL, is_gimple_val, fb_rvalue);
4074 #ifdef ENABLE_CHECKING
4075 /* Compare types A and B for a "close enough" match. */
4078 cpt_same_type (tree a, tree b)
4080 if (lang_hooks.types_compatible_p (a, b))
4083 /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't
4084 link them together. This routine is intended to catch type errors
4085 that will affect the optimizers, and the optimizers don't add new
4086 dereferences of function pointers, so ignore it. */
4087 if ((TREE_CODE (a) == FUNCTION_TYPE || TREE_CODE (a) == METHOD_TYPE)
4088 && (TREE_CODE (b) == FUNCTION_TYPE || TREE_CODE (b) == METHOD_TYPE))
4091 /* ??? The C FE pushes type qualifiers after the fact into the type of
4092 the element from the type of the array. See build_unary_op's handling
4093 of ADDR_EXPR. This seems wrong -- if we were going to do this, we
4094 should have done it when creating the variable in the first place.
4095 Alternately, why aren't the two array types made variants? */
4096 if (TREE_CODE (a) == ARRAY_TYPE && TREE_CODE (b) == ARRAY_TYPE)
4097 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4099 /* And because of those, we have to recurse down through pointers. */
4100 if (POINTER_TYPE_P (a) && POINTER_TYPE_P (b))
4101 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4106 /* Check for some cases of the front end missing cast expressions.
4107 The type of a dereference should correspond to the pointer type;
4108 similarly the type of an address should match its object. */
4111 check_pointer_types_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
4112 void *data ATTRIBUTE_UNUSED)
4115 tree ptype, otype, dtype;
4117 switch (TREE_CODE (t))
4121 otype = TREE_TYPE (t);
4122 ptype = TREE_TYPE (TREE_OPERAND (t, 0));
4123 dtype = TREE_TYPE (ptype);
4124 if (!cpt_same_type (otype, dtype))
4129 ptype = TREE_TYPE (t);
4130 otype = TREE_TYPE (TREE_OPERAND (t, 0));
4131 dtype = TREE_TYPE (ptype);
4132 if (!cpt_same_type (otype, dtype))
4134 /* &array is allowed to produce a pointer to the element, rather than
4135 a pointer to the array type. We must allow this in order to
4136 properly represent assigning the address of an array in C into
4137 pointer to the element type. */
4138 if (TREE_CODE (otype) == ARRAY_TYPE
4139 && POINTER_TYPE_P (ptype)
4140 && cpt_same_type (TREE_TYPE (otype), dtype))
4155 /* Gimplify the body of statements pointed by BODY_P. FNDECL is the
4156 function decl containing BODY. */
4159 gimplify_body (tree *body_p, tree fndecl)
4161 location_t saved_location = input_location;
4164 timevar_push (TV_TREE_GIMPLIFY);
4165 push_gimplify_context ();
4167 /* Unshare most shared trees in the body and in that of any nested functions.
4168 It would seem we don't have to do this for nested functions because
4169 they are supposed to be output and then the outer function gimplified
4170 first, but the g++ front end doesn't always do it that way. */
4171 unshare_body (body_p, fndecl);
4172 unvisit_body (body_p, fndecl);
4174 /* Make sure input_location isn't set to something wierd. */
4175 input_location = DECL_SOURCE_LOCATION (fndecl);
4177 /* Gimplify the function's body. */
4178 gimplify_stmt (body_p);
4181 /* Unshare again, in case gimplification was sloppy. */
4182 unshare_all_trees (body);
4185 body = alloc_stmt_list ();
4186 else if (TREE_CODE (body) == STATEMENT_LIST)
4188 tree t = expr_only (*body_p);
4193 /* If there isn't an outer BIND_EXPR, add one. */
4194 if (TREE_CODE (body) != BIND_EXPR)
4196 tree b = build (BIND_EXPR, void_type_node, NULL_TREE,
4197 NULL_TREE, NULL_TREE);
4198 TREE_SIDE_EFFECTS (b) = 1;
4199 append_to_statement_list_force (body, &BIND_EXPR_BODY (b));
4204 pop_gimplify_context (body);
4206 #ifdef ENABLE_CHECKING
4207 walk_tree (body_p, check_pointer_types_r, NULL, NULL);
4210 timevar_pop (TV_TREE_GIMPLIFY);
4211 input_location = saved_location;
4214 /* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL
4215 node for the function we want to gimplify. */
4218 gimplify_function_tree (tree fndecl)
4222 oldfn = current_function_decl;
4223 current_function_decl = fndecl;
4225 gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl);
4227 /* If we're instrumenting function entry/exit, then prepend the call to
4228 the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
4229 catch the exit hook. */
4230 /* ??? Add some way to ignore exceptions for this TFE. */
4231 if (flag_instrument_function_entry_exit
4232 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl))
4236 tf = build (TRY_FINALLY_EXPR, void_type_node, NULL, NULL);
4237 TREE_SIDE_EFFECTS (tf) = 1;
4238 x = DECL_SAVED_TREE (fndecl);
4239 append_to_statement_list (x, &TREE_OPERAND (tf, 0));
4240 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_EXIT];
4241 x = build_function_call_expr (x, NULL);
4242 append_to_statement_list (x, &TREE_OPERAND (tf, 1));
4244 bind = build (BIND_EXPR, void_type_node, NULL, NULL, NULL);
4245 TREE_SIDE_EFFECTS (bind) = 1;
4246 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_ENTER];
4247 x = build_function_call_expr (x, NULL);
4248 append_to_statement_list (x, &BIND_EXPR_BODY (bind));
4249 append_to_statement_list (tf, &BIND_EXPR_BODY (bind));
4251 DECL_SAVED_TREE (fndecl) = bind;
4254 current_function_decl = oldfn;
4257 #include "gt-gimplify.h"