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 /* Create a stack of the subexpressions so later we can walk them in
1513 order from inner to outer. */
1514 VARRAY_TREE_INIT (stack, 10, "stack");
1516 /* We can either handle REALPART_EXPR, IMAGEPART_EXPR anything that
1517 handled_components can deal with. */
1519 (handled_component_p (*p)
1520 || TREE_CODE (*p) == REALPART_EXPR || TREE_CODE (*p) == IMAGPART_EXPR);
1521 p = &TREE_OPERAND (*p, 0))
1522 VARRAY_PUSH_TREE (stack, *p);
1524 #if defined ENABLE_CHECKING
1525 if (VARRAY_ACTIVE_SIZE (stack) == 0)
1529 /* Now STACK is a stack of pointers to all the refs we've walked through
1530 and P points to the innermost expression.
1532 Java requires that we elaborated nodes in source order. That
1533 means we must gimplify the inner expression followed by each of
1534 the indices, in order. But we can't gimplify the inner
1535 expression until we deal with any variable bounds, sizes, or
1536 positions in order to deal with PLACEHOLDER_EXPRs.
1538 So we do this in three steps. First we deal with the annotations
1539 for any variables in the components, then we gimplify the base,
1540 then we gimplify any indices, from left to right. */
1541 for (i = VARRAY_ACTIVE_SIZE (stack) - 1; i >= 0; i--)
1543 tree t = VARRAY_TREE (stack, i);
1545 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1547 /* Gimplify the low bound and element type size and put them into
1548 the ARRAY_REF. If these values are set, they have already been
1550 if (!TREE_OPERAND (t, 2))
1552 tree low = unshare_expr (array_ref_low_bound (t));
1553 if (!is_gimple_min_invariant (low))
1555 TREE_OPERAND (t, 2) = low;
1556 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1557 is_gimple_tmp_reg, fb_rvalue);
1558 ret = MIN (ret, tret);
1562 if (!TREE_OPERAND (t, 3))
1564 tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
1565 tree elmt_size = unshare_expr (array_ref_element_size (t));
1566 tree factor = size_int (TYPE_ALIGN (elmt_type) / BITS_PER_UNIT);
1568 /* Divide the element size by the alignment of the element
1570 elmt_size = size_binop (EXACT_DIV_EXPR, elmt_size, factor);
1572 if (!is_gimple_min_invariant (elmt_size))
1574 TREE_OPERAND (t, 3) = elmt_size;
1575 tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p,
1576 is_gimple_tmp_reg, fb_rvalue);
1577 ret = MIN (ret, tret);
1581 else if (TREE_CODE (t) == COMPONENT_REF)
1583 /* Set the field offset into T and gimplify it. */
1584 if (!TREE_OPERAND (t, 2))
1586 tree offset = unshare_expr (component_ref_field_offset (t));
1587 tree field = TREE_OPERAND (t, 1);
1589 = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
1591 /* Divide the offset by its alignment. */
1592 offset = size_binop (EXACT_DIV_EXPR, offset, factor);
1594 if (!is_gimple_min_invariant (offset))
1596 TREE_OPERAND (t, 2) = offset;
1597 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1598 is_gimple_tmp_reg, fb_rvalue);
1599 ret = MIN (ret, tret);
1605 /* Step 2 is to gimplify the base expression. */
1606 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1607 ret = MIN (ret, tret);
1609 /* And finally, the indices and operands to BIT_FIELD_REF. During this
1610 loop we also remove any useless conversions. */
1611 for (; VARRAY_ACTIVE_SIZE (stack) > 0; )
1613 tree t = VARRAY_TOP_TREE (stack);
1615 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1617 /* Gimplify the dimension.
1618 Temporary fix for gcc.c-torture/execute/20040313-1.c.
1619 Gimplify non-constant array indices into a temporary
1621 FIXME - The real fix is to gimplify post-modify
1622 expressions into a minimal gimple lvalue. However, that
1623 exposes bugs in alias analysis. The alias analyzer does
1624 not handle &PTR->FIELD very well. Will fix after the
1625 branch is merged into mainline (dnovillo 2004-05-03). */
1626 if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
1628 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1629 is_gimple_tmp_reg, fb_rvalue);
1630 ret = MIN (ret, tret);
1633 else if (TREE_CODE (t) == BIT_FIELD_REF)
1635 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1636 is_gimple_val, fb_rvalue);
1637 ret = MIN (ret, tret);
1638 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1639 is_gimple_val, fb_rvalue);
1640 ret = MIN (ret, tret);
1643 STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0));
1645 /* The innermost expression P may have originally had TREE_SIDE_EFFECTS
1646 set which would have caused all the outer expressions in EXPR_P
1647 leading to P to also have had TREE_SIDE_EFFECTS set. */
1648 recalculate_side_effects (t);
1652 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1653 ret = MIN (ret, tret);
1655 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
1656 if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF)
1658 canonicalize_component_ref (expr_p);
1659 ret = MIN (ret, GS_OK);
1665 /* Gimplify the self modifying expression pointed by EXPR_P (++, --, +=, -=).
1667 PRE_P points to the list where side effects that must happen before
1668 *EXPR_P should be stored.
1670 POST_P points to the list where side effects that must happen after
1671 *EXPR_P should be stored.
1673 WANT_VALUE is nonzero iff we want to use the value of this expression
1674 in another expression. */
1676 static enum gimplify_status
1677 gimplify_self_mod_expr (tree *expr_p, tree *pre_p, tree *post_p,
1680 enum tree_code code;
1681 tree lhs, lvalue, rhs, t1;
1683 enum tree_code arith_code;
1684 enum gimplify_status ret;
1686 code = TREE_CODE (*expr_p);
1688 #if defined ENABLE_CHECKING
1689 if (code != POSTINCREMENT_EXPR
1690 && code != POSTDECREMENT_EXPR
1691 && code != PREINCREMENT_EXPR
1692 && code != PREDECREMENT_EXPR)
1696 /* Prefix or postfix? */
1697 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
1698 /* Faster to treat as prefix if result is not used. */
1699 postfix = want_value;
1703 /* Add or subtract? */
1704 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
1705 arith_code = PLUS_EXPR;
1707 arith_code = MINUS_EXPR;
1709 /* Gimplify the LHS into a GIMPLE lvalue. */
1710 lvalue = TREE_OPERAND (*expr_p, 0);
1711 ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
1712 if (ret == GS_ERROR)
1715 /* Extract the operands to the arithmetic operation. */
1717 rhs = TREE_OPERAND (*expr_p, 1);
1719 /* For postfix operator, we evaluate the LHS to an rvalue and then use
1720 that as the result value and in the postqueue operation. */
1723 ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
1724 if (ret == GS_ERROR)
1728 t1 = build (arith_code, TREE_TYPE (*expr_p), lhs, rhs);
1729 t1 = build (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
1733 gimplify_and_add (t1, post_p);
1744 /* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
1747 maybe_with_size_expr (tree *expr_p)
1749 tree expr, type, size;
1752 type = TREE_TYPE (expr);
1753 if (type == error_mark_node)
1756 size = TYPE_SIZE_UNIT (type);
1757 if (size && TREE_CODE (size) != INTEGER_CST)
1759 size = unshare_expr (size);
1760 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr);
1761 *expr_p = build2 (WITH_SIZE_EXPR, type, expr, size);
1765 /* Subroutine of gimplify_call_expr: Gimplify a single argument. */
1767 static enum gimplify_status
1768 gimplify_arg (tree *expr_p, tree *pre_p)
1770 bool (*test) (tree);
1773 /* In general, we allow lvalues for function arguments to avoid
1774 extra overhead of copying large aggregates out of even larger
1775 aggregates into temporaries only to copy the temporaries to
1776 the argument list. Make optimizers happy by pulling out to
1777 temporaries those types that fit in registers. */
1778 if (is_gimple_reg_type (TREE_TYPE (*expr_p)))
1779 test = is_gimple_val, fb = fb_rvalue;
1781 test = is_gimple_lvalue, fb = fb_either;
1783 /* If this is a variable sized type, we must remember the size. */
1784 maybe_with_size_expr (expr_p);
1786 /* There is a sequence point before a function call. Side effects in
1787 the argument list must occur before the actual call. So, when
1788 gimplifying arguments, force gimplify_expr to use an internal
1789 post queue which is then appended to the end of PRE_P. */
1790 return gimplify_expr (expr_p, pre_p, NULL, test, fb);
1793 /* Gimplify the CALL_EXPR node pointed by EXPR_P. PRE_P points to the
1794 list where side effects that must happen before *EXPR_P should be stored.
1795 WANT_VALUE is true if the result of the call is desired. */
1797 static enum gimplify_status
1798 gimplify_call_expr (tree *expr_p, tree *pre_p, bool want_value)
1802 enum gimplify_status ret;
1804 #if defined ENABLE_CHECKING
1805 if (TREE_CODE (*expr_p) != CALL_EXPR)
1809 /* For reliable diagnostics during inlining, it is necessary that
1810 every call_expr be annotated with file and line. */
1811 if (! EXPR_HAS_LOCATION (*expr_p))
1812 SET_EXPR_LOCATION (*expr_p, input_location);
1814 /* This may be a call to a builtin function.
1816 Builtin function calls may be transformed into different
1817 (and more efficient) builtin function calls under certain
1818 circumstances. Unfortunately, gimplification can muck things
1819 up enough that the builtin expanders are not aware that certain
1820 transformations are still valid.
1822 So we attempt transformation/gimplification of the call before
1823 we gimplify the CALL_EXPR. At this time we do not manage to
1824 transform all calls in the same manner as the expanders do, but
1825 we do transform most of them. */
1826 decl = get_callee_fndecl (*expr_p);
1827 if (decl && DECL_BUILT_IN (decl))
1831 /* If it is allocation of stack, record the need to restore the memory
1832 when the enclosing bind_expr is exited. */
1833 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_STACK_ALLOC)
1834 gimplify_ctxp->save_stack = true;
1836 /* If it is restore of the stack, reset it, since it means we are
1837 regimplifying the bind_expr. Note that we use the fact that
1838 for try_finally_expr, try part is processed first. */
1839 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_STACK_RESTORE)
1840 gimplify_ctxp->save_stack = false;
1842 new = simplify_builtin (*expr_p, !want_value);
1844 if (new && new != *expr_p)
1846 /* There was a transformation of this call which computes the
1847 same value, but in a more efficient way. Return and try
1853 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_VA_START)
1854 /* Avoid gimplifying the second argument to va_start, which needs
1855 to be the plain PARM_DECL. */
1856 return gimplify_arg (&TREE_VALUE (TREE_OPERAND (*expr_p, 1)), pre_p);
1859 /* There is a sequence point before the call, so any side effects in
1860 the calling expression must occur before the actual call. Force
1861 gimplify_expr to use an internal post queue. */
1862 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, NULL,
1863 is_gimple_call_addr, fb_rvalue);
1865 if (PUSH_ARGS_REVERSED)
1866 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1867 for (arglist = TREE_OPERAND (*expr_p, 1); arglist;
1868 arglist = TREE_CHAIN (arglist))
1870 enum gimplify_status t;
1872 t = gimplify_arg (&TREE_VALUE (arglist), pre_p);
1877 if (PUSH_ARGS_REVERSED)
1878 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1880 /* Try this again in case gimplification exposed something. */
1881 if (ret != GS_ERROR && decl && DECL_BUILT_IN (decl))
1883 tree new = simplify_builtin (*expr_p, !want_value);
1885 if (new && new != *expr_p)
1887 /* There was a transformation of this call which computes the
1888 same value, but in a more efficient way. Return and try
1895 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
1896 decl. This allows us to eliminate redundant or useless
1897 calls to "const" functions. */
1898 if (TREE_CODE (*expr_p) == CALL_EXPR
1899 && (call_expr_flags (*expr_p) & (ECF_CONST | ECF_PURE)))
1900 TREE_SIDE_EFFECTS (*expr_p) = 0;
1905 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
1906 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
1908 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
1909 condition is true or false, respectively. If null, we should generate
1910 our own to skip over the evaluation of this specific expression.
1912 This function is the tree equivalent of do_jump.
1914 shortcut_cond_r should only be called by shortcut_cond_expr. */
1917 shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p)
1919 tree local_label = NULL_TREE;
1920 tree t, expr = NULL;
1922 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
1923 retain the shortcut semantics. Just insert the gotos here;
1924 shortcut_cond_expr will append the real blocks later. */
1925 if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
1927 /* Turn if (a && b) into
1929 if (a); else goto no;
1930 if (b) goto yes; else goto no;
1933 if (false_label_p == NULL)
1934 false_label_p = &local_label;
1936 t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p);
1937 append_to_statement_list (t, &expr);
1939 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1941 append_to_statement_list (t, &expr);
1943 else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
1945 /* Turn if (a || b) into
1948 if (b) goto yes; else goto no;
1951 if (true_label_p == NULL)
1952 true_label_p = &local_label;
1954 t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL);
1955 append_to_statement_list (t, &expr);
1957 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1959 append_to_statement_list (t, &expr);
1961 else if (TREE_CODE (pred) == COND_EXPR)
1963 /* As long as we're messing with gotos, turn if (a ? b : c) into
1965 if (b) goto yes; else goto no;
1967 if (c) goto yes; else goto no; */
1968 expr = build (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
1969 shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1971 shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
1976 expr = build (COND_EXPR, void_type_node, pred,
1977 build_and_jump (true_label_p),
1978 build_and_jump (false_label_p));
1983 t = build1 (LABEL_EXPR, void_type_node, local_label);
1984 append_to_statement_list (t, &expr);
1991 shortcut_cond_expr (tree expr)
1993 tree pred = TREE_OPERAND (expr, 0);
1994 tree then_ = TREE_OPERAND (expr, 1);
1995 tree else_ = TREE_OPERAND (expr, 2);
1996 tree true_label, false_label, end_label, t;
1998 tree *false_label_p;
1999 bool emit_end, emit_false;
2000 bool then_se = then_ && TREE_SIDE_EFFECTS (then_);
2001 bool else_se = else_ && TREE_SIDE_EFFECTS (else_);
2003 /* First do simple transformations. */
2006 /* If there is no 'else', turn (a && b) into if (a) if (b). */
2007 while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2009 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2010 then_ = shortcut_cond_expr (expr);
2011 pred = TREE_OPERAND (pred, 0);
2012 expr = build (COND_EXPR, void_type_node, pred, then_, NULL_TREE);
2017 /* If there is no 'then', turn
2020 if (a); else if (b); else d. */
2021 while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2023 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2024 else_ = shortcut_cond_expr (expr);
2025 pred = TREE_OPERAND (pred, 0);
2026 expr = build (COND_EXPR, void_type_node, pred, NULL_TREE, else_);
2030 /* If we're done, great. */
2031 if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
2032 && TREE_CODE (pred) != TRUTH_ORIF_EXPR)
2035 /* Otherwise we need to mess with gotos. Change
2038 if (a); else goto no;
2041 and recursively gimplify the condition. */
2043 true_label = false_label = end_label = NULL_TREE;
2045 /* If our arms just jump somewhere, hijack those labels so we don't
2046 generate jumps to jumps. */
2049 && TREE_CODE (then_) == GOTO_EXPR
2050 && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
2052 true_label = GOTO_DESTINATION (then_);
2058 && TREE_CODE (else_) == GOTO_EXPR
2059 && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
2061 false_label = GOTO_DESTINATION (else_);
2066 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2068 true_label_p = &true_label;
2070 true_label_p = NULL;
2072 /* The 'else' branch also needs a label if it contains interesting code. */
2073 if (false_label || else_se)
2074 false_label_p = &false_label;
2076 false_label_p = NULL;
2078 /* If there was nothing else in our arms, just forward the label(s). */
2079 if (!then_se && !else_se)
2080 return shortcut_cond_r (pred, true_label_p, false_label_p);
2082 /* If our last subexpression already has a terminal label, reuse it. */
2084 expr = expr_last (else_);
2086 expr = expr_last (then_);
2089 if (expr && TREE_CODE (expr) == LABEL_EXPR)
2090 end_label = LABEL_EXPR_LABEL (expr);
2092 /* If we don't care about jumping to the 'else' branch, jump to the end
2093 if the condition is false. */
2095 false_label_p = &end_label;
2097 /* We only want to emit these labels if we aren't hijacking them. */
2098 emit_end = (end_label == NULL_TREE);
2099 emit_false = (false_label == NULL_TREE);
2101 pred = shortcut_cond_r (pred, true_label_p, false_label_p);
2104 append_to_statement_list (pred, &expr);
2106 append_to_statement_list (then_, &expr);
2109 t = build_and_jump (&end_label);
2110 append_to_statement_list (t, &expr);
2113 t = build1 (LABEL_EXPR, void_type_node, false_label);
2114 append_to_statement_list (t, &expr);
2116 append_to_statement_list (else_, &expr);
2118 if (emit_end && end_label)
2120 t = build1 (LABEL_EXPR, void_type_node, end_label);
2121 append_to_statement_list (t, &expr);
2127 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2130 gimple_boolify (tree expr)
2132 tree type = TREE_TYPE (expr);
2134 if (TREE_CODE (type) == BOOLEAN_TYPE)
2137 /* If this is the predicate of a COND_EXPR, it might not even be a
2139 expr = lang_hooks.truthvalue_conversion (expr);
2141 switch (TREE_CODE (expr))
2143 case TRUTH_AND_EXPR:
2145 case TRUTH_XOR_EXPR:
2146 case TRUTH_ANDIF_EXPR:
2147 case TRUTH_ORIF_EXPR:
2148 /* Also boolify the arguments of truth exprs. */
2149 TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
2152 case TRUTH_NOT_EXPR:
2153 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2156 case EQ_EXPR: case NE_EXPR:
2157 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2158 /* These expressions always produce boolean results. */
2159 TREE_TYPE (expr) = boolean_type_node;
2163 /* Other expressions that get here must have boolean values, but
2164 might need to be converted to the appropriate mode. */
2165 return convert (boolean_type_node, expr);
2169 /* Convert the conditional expression pointed by EXPR_P '(p) ? a : b;'
2178 The second form is used when *EXPR_P is of type void.
2180 TARGET is the tree for T1 above.
2182 PRE_P points to the list where side effects that must happen before
2183 *EXPR_P should be stored. */
2185 static enum gimplify_status
2186 gimplify_cond_expr (tree *expr_p, tree *pre_p, tree target)
2188 tree expr = *expr_p;
2189 tree tmp, tmp2, type;
2190 enum gimplify_status ret;
2192 type = TREE_TYPE (expr);
2194 TREE_TYPE (expr) = void_type_node;
2196 /* If this COND_EXPR has a value, copy the values into a temporary within
2198 else if (! VOID_TYPE_P (type))
2202 ret = gimplify_expr (&target, pre_p, NULL,
2203 is_gimple_min_lval, fb_lvalue);
2204 if (ret != GS_ERROR)
2207 tmp2 = unshare_expr (target);
2211 tmp2 = tmp = create_tmp_var (TREE_TYPE (expr), "iftmp");
2215 /* Build the then clause, 't1 = a;'. But don't build an assignment
2216 if this branch is void; in C++ it can be, if it's a throw. */
2217 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2218 TREE_OPERAND (expr, 1)
2219 = build (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 1));
2221 /* Build the else clause, 't1 = b;'. */
2222 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2223 TREE_OPERAND (expr, 2)
2224 = build (MODIFY_EXPR, void_type_node, tmp2, TREE_OPERAND (expr, 2));
2226 TREE_TYPE (expr) = void_type_node;
2227 recalculate_side_effects (expr);
2229 /* Move the COND_EXPR to the prequeue. */
2230 gimplify_and_add (expr, pre_p);
2236 /* Make sure the condition has BOOLEAN_TYPE. */
2237 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2239 /* Break apart && and || conditions. */
2240 if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
2241 || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
2243 expr = shortcut_cond_expr (expr);
2245 if (expr != *expr_p)
2249 /* We can't rely on gimplify_expr to re-gimplify the expanded
2250 form properly, as cleanups might cause the target labels to be
2251 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2252 set up a conditional context. */
2253 gimple_push_condition ();
2254 gimplify_stmt (expr_p);
2255 gimple_pop_condition (pre_p);
2261 /* Now do the normal gimplification. */
2262 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2263 is_gimple_condexpr, fb_rvalue);
2265 gimple_push_condition ();
2267 gimplify_to_stmt_list (&TREE_OPERAND (expr, 1));
2268 gimplify_to_stmt_list (&TREE_OPERAND (expr, 2));
2269 recalculate_side_effects (expr);
2271 gimple_pop_condition (pre_p);
2273 if (ret == GS_ERROR)
2275 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2277 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 2)))
2278 /* Rewrite "if (a); else b" to "if (!a) b" */
2280 TREE_OPERAND (expr, 0) = invert_truthvalue (TREE_OPERAND (expr, 0));
2281 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2282 is_gimple_condexpr, fb_rvalue);
2284 tmp = TREE_OPERAND (expr, 1);
2285 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 2);
2286 TREE_OPERAND (expr, 2) = tmp;
2289 /* Both arms are empty; replace the COND_EXPR with its predicate. */
2290 expr = TREE_OPERAND (expr, 0);
2296 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2297 a call to __builtin_memcpy. */
2299 static enum gimplify_status
2300 gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value)
2302 tree args, t, to, to_ptr, from;
2304 to = TREE_OPERAND (*expr_p, 0);
2305 from = TREE_OPERAND (*expr_p, 1);
2307 args = tree_cons (NULL, size, NULL);
2309 t = build_fold_addr_expr (from);
2310 args = tree_cons (NULL, t, args);
2312 to_ptr = build_fold_addr_expr (to);
2313 args = tree_cons (NULL, to_ptr, args);
2314 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
2315 t = build_function_call_expr (t, args);
2319 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2320 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2327 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2328 a call to __builtin_memset. In this case we know that the RHS is
2329 a CONSTRUCTOR with an empty element list. */
2331 static enum gimplify_status
2332 gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value)
2334 tree args, t, to, to_ptr;
2336 to = TREE_OPERAND (*expr_p, 0);
2338 args = tree_cons (NULL, size, NULL);
2340 args = tree_cons (NULL, integer_zero_node, args);
2342 to_ptr = build_fold_addr_expr (to);
2343 args = tree_cons (NULL, to_ptr, args);
2344 t = implicit_built_in_decls[BUILT_IN_MEMSET];
2345 t = build_function_call_expr (t, args);
2349 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2350 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2357 /* A subroutine of gimplify_modify_expr. Break out elements of a
2358 CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.
2360 Note that we still need to clear any elements that don't have explicit
2361 initializers, so if not all elements are initialized we keep the
2362 original MODIFY_EXPR, we just remove all of the constructor elements. */
2364 static enum gimplify_status
2365 gimplify_init_constructor (tree *expr_p, tree *pre_p,
2366 tree *post_p, bool want_value)
2368 tree object = TREE_OPERAND (*expr_p, 0);
2369 tree ctor = TREE_OPERAND (*expr_p, 1);
2370 tree type = TREE_TYPE (ctor);
2371 enum gimplify_status ret;
2374 if (TREE_CODE (ctor) != CONSTRUCTOR)
2375 return GS_UNHANDLED;
2377 elt_list = CONSTRUCTOR_ELTS (ctor);
2380 switch (TREE_CODE (type))
2384 case QUAL_UNION_TYPE:
2387 HOST_WIDE_INT i, num_elements, num_nonzero_elements;
2388 HOST_WIDE_INT num_nonconstant_elements;
2391 /* Aggregate types must lower constructors to initialization of
2392 individual elements. The exception is that a CONSTRUCTOR node
2393 with no elements indicates zero-initialization of the whole. */
2394 if (elt_list == NULL)
2402 return GS_UNHANDLED;
2405 categorize_ctor_elements (ctor, &num_nonzero_elements,
2406 &num_nonconstant_elements);
2407 num_elements = count_type_elements (TREE_TYPE (ctor));
2409 /* If a const aggregate variable is being initialized, then it
2410 should never be a lose to promote the variable to be static. */
2411 if (num_nonconstant_elements == 0
2412 && TREE_READONLY (object)
2413 && TREE_CODE (object) == VAR_DECL)
2415 DECL_INITIAL (object) = ctor;
2416 TREE_STATIC (object) = 1;
2417 if (!DECL_NAME (object))
2418 DECL_NAME (object) = create_tmp_var_name ("C");
2419 walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL);
2421 /* ??? C++ doesn't automatically append a .<number> to the
2422 assembler name, and even when it does, it looks a FE private
2423 data structures to figure out what that number should be,
2424 which are not set for this variable. I suppose this is
2425 important for local statics for inline functions, which aren't
2426 "local" in the object file sense. So in order to get a unique
2427 TU-local symbol, we must invoke the lhd version now. */
2428 lhd_set_decl_assembler_name (object);
2430 *expr_p = NULL_TREE;
2434 /* If there are "lots" of initialized elements, and all of them
2435 are valid address constants, then the entire initializer can
2436 be dropped to memory, and then memcpy'd out. */
2437 if (num_nonconstant_elements == 0)
2439 HOST_WIDE_INT size = int_size_in_bytes (type);
2442 /* ??? We can still get unbounded array types, at least
2443 from the C++ front end. This seems wrong, but attempt
2444 to work around it for now. */
2447 size = int_size_in_bytes (TREE_TYPE (object));
2449 TREE_TYPE (ctor) = type = TREE_TYPE (object);
2452 /* Find the maximum alignment we can assume for the object. */
2453 /* ??? Make use of DECL_OFFSET_ALIGN. */
2454 if (DECL_P (object))
2455 align = DECL_ALIGN (object);
2457 align = TYPE_ALIGN (type);
2459 if (size > 0 && !can_move_by_pieces (size, align))
2461 tree new = create_tmp_var_raw (type, "C");
2462 gimple_add_tmp_var (new);
2463 TREE_STATIC (new) = 1;
2464 TREE_READONLY (new) = 1;
2465 DECL_INITIAL (new) = ctor;
2466 if (align > DECL_ALIGN (new))
2468 DECL_ALIGN (new) = align;
2469 DECL_USER_ALIGN (new) = 1;
2471 walk_tree (&DECL_INITIAL (new), force_labels_r, NULL, NULL);
2473 TREE_OPERAND (*expr_p, 1) = new;
2478 /* If there are "lots" of initialized elements, even discounting
2479 those that are not address constants (and thus *must* be
2480 computed at runtime), then partition the constructor into
2481 constant and non-constant parts. Block copy the constant
2482 parts in, then generate code for the non-constant parts. */
2483 /* TODO. There's code in cp/typeck.c to do this. */
2485 /* If there are "lots" of zeros, then block clear the object first. */
2487 if (num_elements - num_nonzero_elements > CLEAR_RATIO
2488 && num_nonzero_elements < num_elements/4)
2491 /* ??? This bit ought not be needed. For any element not present
2492 in the initializer, we should simply set them to zero. Except
2493 we'd need to *find* the elements that are not present, and that
2494 requires trickery to avoid quadratic compile-time behavior in
2495 large cases or excessive memory use in small cases. */
2498 HOST_WIDE_INT len = list_length (elt_list);
2499 if (TREE_CODE (type) == ARRAY_TYPE)
2501 tree nelts = array_type_nelts (type);
2502 if (!host_integerp (nelts, 1)
2503 || tree_low_cst (nelts, 1) + 1 != len)
2506 else if (len != fields_length (type))
2512 /* Zap the CONSTRUCTOR element list, which simplifies this case.
2513 Note that we still have to gimplify, in order to handle the
2514 case of variable sized types. Make an unshared copy of
2515 OBJECT before that so we can match a PLACEHOLDER_EXPR to it
2516 later, if needed. */
2517 CONSTRUCTOR_ELTS (ctor) = NULL_TREE;
2518 object = unshare_expr (TREE_OPERAND (*expr_p, 0));
2519 gimplify_stmt (expr_p);
2520 append_to_statement_list (*expr_p, pre_p);
2523 for (i = 0; elt_list; i++, elt_list = TREE_CHAIN (elt_list))
2525 tree purpose, value, cref, init;
2527 purpose = TREE_PURPOSE (elt_list);
2528 value = TREE_VALUE (elt_list);
2530 if (cleared && initializer_zerop (value))
2533 if (TREE_CODE (type) == ARRAY_TYPE)
2535 tree t = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object)));
2537 /* ??? Here's to hoping the front end fills in all of the
2538 indicies, so we don't have to figure out what's missing
2542 /* ??? Need to handle this. */
2543 if (TREE_CODE (purpose) == RANGE_EXPR)
2546 cref = build (ARRAY_REF, t, unshare_expr (object), purpose,
2547 NULL_TREE, NULL_TREE);
2550 cref = build (COMPONENT_REF, TREE_TYPE (purpose),
2551 unshare_expr (object), purpose, NULL_TREE);
2553 init = build (MODIFY_EXPR, TREE_TYPE (purpose), cref, value);
2555 /* Each member initialization is a full-expression. */
2556 gimplify_and_add (init, pre_p);
2559 *expr_p = NULL_TREE;
2567 /* Extract the real and imaginary parts out of the ctor. */
2571 r = TREE_VALUE (elt_list);
2572 elt_list = TREE_CHAIN (elt_list);
2575 i = TREE_VALUE (elt_list);
2576 if (TREE_CHAIN (elt_list))
2580 if (r == NULL || i == NULL)
2582 tree zero = convert (TREE_TYPE (type), integer_zero_node);
2589 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
2590 represent creation of a complex value. */
2591 if (TREE_CONSTANT (r) && TREE_CONSTANT (i))
2593 ctor = build_complex (type, r, i);
2594 TREE_OPERAND (*expr_p, 1) = ctor;
2598 ctor = build (COMPLEX_EXPR, type, r, i);
2599 TREE_OPERAND (*expr_p, 1) = ctor;
2600 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
2601 is_gimple_tmp_rhs, fb_rvalue);
2607 /* Go ahead and simplify constant constructors to VECTOR_CST. */
2608 if (TREE_CONSTANT (ctor))
2609 TREE_OPERAND (*expr_p, 1) = build_vector (type, elt_list);
2612 /* Vector types use CONSTRUCTOR all the way through gimple
2613 compilation as a general initializer. */
2614 for (; elt_list; elt_list = TREE_CHAIN (elt_list))
2616 enum gimplify_status tret;
2617 tret = gimplify_expr (&TREE_VALUE (elt_list), pre_p, post_p,
2618 is_gimple_constructor_elt, fb_rvalue);
2619 if (tret == GS_ERROR)
2626 /* So how did we get a CONSTRUCTOR for a scalar type? */
2630 if (ret == GS_ERROR)
2632 else if (want_value)
2634 append_to_statement_list (*expr_p, pre_p);
2642 /* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs
2643 based on the code of the RHS. We loop for as long as something changes. */
2645 static enum gimplify_status
2646 gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p,
2647 tree *post_p, bool want_value)
2649 enum gimplify_status ret = GS_OK;
2651 while (ret != GS_UNHANDLED)
2652 switch (TREE_CODE (*from_p))
2656 /* If we are initializing something from a TARGET_EXPR, strip the
2657 TARGET_EXPR and initialize it directly, if possible. This can't
2658 be done if the initializer is void, since that implies that the
2659 temporary is set in some non-trivial way.
2661 ??? What about code that pulls out the temp and uses it
2662 elsewhere? I think that such code never uses the TARGET_EXPR as
2663 an initializer. If I'm wrong, we'll abort because the temp won't
2664 have any RTL. In that case, I guess we'll need to replace
2665 references somehow. */
2666 tree init = TARGET_EXPR_INITIAL (*from_p);
2668 if (!VOID_TYPE_P (TREE_TYPE (init)))
2679 /* Remove any COMPOUND_EXPR in the RHS so the following cases will be
2681 gimplify_compound_expr (from_p, pre_p, true);
2686 /* If we're initializing from a CONSTRUCTOR, break this into
2687 individual MODIFY_EXPRs. */
2688 return gimplify_init_constructor (expr_p, pre_p, post_p, want_value);
2691 /* If we're assigning to a non-register type, push the assignment
2692 down into the branches. This is mandatory for ADDRESSABLE types,
2693 since we cannot generate temporaries for such, but it saves a
2694 copy in other cases as well. */
2695 if (!is_gimple_reg_type (TREE_TYPE (*from_p)))
2698 return gimplify_cond_expr (expr_p, pre_p, *to_p);
2712 /* Return true if T is either a valid GIMPLE operand or is an
2713 INDIRECT_REF (the latter is valid since we'll strip it off). */
2716 is_gimple_addr_expr_arg_or_indirect (tree t)
2718 return (TREE_CODE (t) == INDIRECT_REF || is_gimple_addr_expr_arg (t));
2721 /* Gimplify the MODIFY_EXPR node pointed by EXPR_P.
2727 PRE_P points to the list where side effects that must happen before
2728 *EXPR_P should be stored.
2730 POST_P points to the list where side effects that must happen after
2731 *EXPR_P should be stored.
2733 WANT_VALUE is nonzero iff we want to use the value of this expression
2734 in another expression. */
2736 static enum gimplify_status
2737 gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value)
2739 tree *from_p = &TREE_OPERAND (*expr_p, 1);
2740 tree *to_p = &TREE_OPERAND (*expr_p, 0);
2741 enum gimplify_status ret = GS_UNHANDLED;
2743 #if defined ENABLE_CHECKING
2744 if (TREE_CODE (*expr_p) != MODIFY_EXPR && TREE_CODE (*expr_p) != INIT_EXPR)
2748 /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer useful. */
2749 if (TREE_CODE (*expr_p) == INIT_EXPR)
2750 TREE_SET_CODE (*expr_p, MODIFY_EXPR);
2752 /* See if any simplifications can be done based on what the RHS is. */
2753 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2755 if (ret != GS_UNHANDLED)
2758 /* If the value being copied is of variable width, compute the length
2759 of the copy into a WITH_SIZE_EXPR. Note that we need to do this
2760 before gimplifying any of the operands so that we can resolve any
2761 PLACEHOLDER_EXPRs in the size. Also note that the RTL expander uses
2762 the size of the expression to be copied, not of the destination, so
2763 that is what we must here. */
2764 maybe_with_size_expr (from_p);
2766 ret = gimplify_expr (to_p, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
2767 if (ret == GS_ERROR)
2770 ret = gimplify_expr (from_p, pre_p, post_p,
2771 rhs_predicate_for (*to_p), fb_rvalue);
2772 if (ret == GS_ERROR)
2775 /* Now see if the above changed *from_p to something we handle specially. */
2776 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2778 if (ret != GS_UNHANDLED)
2781 /* If we've got a variable sized assignment between two lvalues (i.e. does
2782 not involve a call), then we can make things a bit more straightforward
2783 by converting the assignment to memcpy or memset. */
2784 if (TREE_CODE (*from_p) == WITH_SIZE_EXPR)
2786 tree from = TREE_OPERAND (*from_p, 0);
2787 tree size = TREE_OPERAND (*from_p, 1);
2789 if (TREE_CODE (from) == CONSTRUCTOR)
2790 return gimplify_modify_expr_to_memset (expr_p, size, want_value);
2791 if (is_gimple_addr_expr_arg (from))
2794 return gimplify_modify_expr_to_memcpy (expr_p, size, want_value);
2798 /* If the destination is already simple, nothing else needed. */
2799 if (is_gimple_tmp_var (*to_p) || !want_value)
2806 append_to_statement_list (*expr_p, pre_p);
2813 /* Gimplify a comparison between two variable-sized objects. Do this
2814 with a call to BUILT_IN_MEMCMP. */
2816 static enum gimplify_status
2817 gimplify_variable_sized_compare (tree *expr_p)
2819 tree op0 = TREE_OPERAND (*expr_p, 0);
2820 tree op1 = TREE_OPERAND (*expr_p, 1);
2823 t = TYPE_SIZE_UNIT (TREE_TYPE (op0));
2824 t = unshare_expr (t);
2825 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, op0);
2826 args = tree_cons (NULL, t, NULL);
2827 t = build_fold_addr_expr (op1);
2828 args = tree_cons (NULL, t, args);
2829 dest = build_fold_addr_expr (op0);
2830 args = tree_cons (NULL, dest, args);
2831 t = implicit_built_in_decls[BUILT_IN_MEMCMP];
2832 t = build_function_call_expr (t, args);
2834 = build (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), t, integer_zero_node);
2839 /* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P
2840 points to the expression to gimplify.
2842 Expressions of the form 'a && b' are gimplified to:
2844 a && b ? true : false
2846 gimplify_cond_expr will do the rest.
2848 PRE_P points to the list where side effects that must happen before
2849 *EXPR_P should be stored. */
2851 static enum gimplify_status
2852 gimplify_boolean_expr (tree *expr_p)
2854 /* Preserve the original type of the expression. */
2855 tree type = TREE_TYPE (*expr_p);
2857 *expr_p = build (COND_EXPR, type, *expr_p,
2858 convert (type, boolean_true_node),
2859 convert (type, boolean_false_node));
2864 /* Gimplifies an expression sequence. This function gimplifies each
2865 expression and re-writes the original expression with the last
2866 expression of the sequence in GIMPLE form.
2868 PRE_P points to the list where the side effects for all the
2869 expressions in the sequence will be emitted.
2871 WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */
2872 /* ??? Should rearrange to share the pre-queue with all the indirect
2873 invocations of gimplify_expr. Would probably save on creations
2874 of statement_list nodes. */
2876 static enum gimplify_status
2877 gimplify_compound_expr (tree *expr_p, tree *pre_p, bool want_value)
2883 tree *sub_p = &TREE_OPERAND (t, 0);
2885 if (TREE_CODE (*sub_p) == COMPOUND_EXPR)
2886 gimplify_compound_expr (sub_p, pre_p, false);
2888 gimplify_stmt (sub_p);
2889 append_to_statement_list (*sub_p, pre_p);
2891 t = TREE_OPERAND (t, 1);
2893 while (TREE_CODE (t) == COMPOUND_EXPR);
2900 gimplify_stmt (expr_p);
2905 /* Gimplifies a statement list. These may be created either by an
2906 enlightened front-end, or by shortcut_cond_expr. */
2908 static enum gimplify_status
2909 gimplify_statement_list (tree *expr_p)
2911 tree_stmt_iterator i = tsi_start (*expr_p);
2913 while (!tsi_end_p (i))
2917 gimplify_stmt (tsi_stmt_ptr (i));
2922 else if (TREE_CODE (t) == STATEMENT_LIST)
2924 tsi_link_before (&i, t, TSI_SAME_STMT);
2934 /* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to
2935 gimplify. After gimplification, EXPR_P will point to a new temporary
2936 that holds the original value of the SAVE_EXPR node.
2938 PRE_P points to the list where side effects that must happen before
2939 *EXPR_P should be stored. */
2941 static enum gimplify_status
2942 gimplify_save_expr (tree *expr_p, tree *pre_p, tree *post_p)
2944 enum gimplify_status ret = GS_ALL_DONE;
2947 #if defined ENABLE_CHECKING
2948 if (TREE_CODE (*expr_p) != SAVE_EXPR)
2952 val = TREE_OPERAND (*expr_p, 0);
2954 /* If the operand is already a GIMPLE temporary, just re-write the
2956 if (is_gimple_tmp_var (val))
2958 /* The operand may be a void-valued expression such as SAVE_EXPRs
2959 generated by the Java frontend for class initialization. It is
2960 being executed only for its side-effects. */
2961 else if (TREE_TYPE (val) == void_type_node)
2963 tree body = TREE_OPERAND (*expr_p, 0);
2964 ret = gimplify_expr (& body, pre_p, post_p, is_gimple_stmt, fb_none);
2965 append_to_statement_list (body, pre_p);
2969 *expr_p = TREE_OPERAND (*expr_p, 0)
2970 = get_initialized_tmp_var (val, pre_p, post_p);
2975 /* Re-write the ADDR_EXPR node pointed by EXPR_P
2982 PRE_P points to the list where side effects that must happen before
2983 *EXPR_P should be stored.
2985 POST_P points to the list where side effects that must happen after
2986 *EXPR_P should be stored. */
2988 static enum gimplify_status
2989 gimplify_addr_expr (tree *expr_p, tree *pre_p, tree *post_p)
2991 tree expr = *expr_p;
2992 tree op0 = TREE_OPERAND (expr, 0);
2993 enum gimplify_status ret;
2995 switch (TREE_CODE (op0))
2998 /* Check if we are dealing with an expression of the form '&*ptr'.
2999 While the front end folds away '&*ptr' into 'ptr', these
3000 expressions may be generated internally by the compiler (e.g.,
3001 builtins like __builtin_va_end). */
3002 *expr_p = TREE_OPERAND (op0, 0);
3007 /* Fold &a[6] to (&a + 6). */
3008 ret = gimplify_array_ref_to_plus (&TREE_OPERAND (expr, 0),
3011 /* This added an INDIRECT_REF. Fold it away. */
3012 *expr_p = TREE_OPERAND (TREE_OPERAND (expr, 0), 0);
3015 case VIEW_CONVERT_EXPR:
3016 /* Take the address of our operand and then convert it to the type of
3019 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3020 all clear. The impact of this transformation is even less clear. */
3021 *expr_p = fold_convert (TREE_TYPE (expr),
3022 build_fold_addr_expr (TREE_OPERAND (op0, 0)));
3027 /* We use fb_either here because the C frontend sometimes takes
3028 the address of a call that returns a struct. */
3029 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, post_p,
3030 is_gimple_addr_expr_arg_or_indirect, fb_either);
3031 if (ret != GS_ERROR)
3033 /* The above may have made an INDIRECT ref (e.g, Ada's NULL_EXPR),
3034 so check for it here. It's not worth checking for the other
3036 if (TREE_CODE (TREE_OPERAND (expr, 0)) == INDIRECT_REF)
3038 *expr_p = TREE_OPERAND (TREE_OPERAND (expr, 0), 0);
3042 /* Make sure TREE_INVARIANT, TREE_CONSTANT, and TREE_SIDE_EFFECTS
3044 recompute_tree_invarant_for_addr_expr (expr);
3046 /* Mark the RHS addressable. */
3047 lang_hooks.mark_addressable (TREE_OPERAND (expr, 0));
3055 /* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple
3056 value; output operands should be a gimple lvalue. */
3058 static enum gimplify_status
3059 gimplify_asm_expr (tree *expr_p, tree *pre_p, tree *post_p)
3061 tree expr = *expr_p;
3062 int noutputs = list_length (ASM_OUTPUTS (expr));
3063 const char **oconstraints
3064 = (const char **) alloca ((noutputs) * sizeof (const char *));
3067 const char *constraint;
3068 bool allows_mem, allows_reg, is_inout;
3069 enum gimplify_status ret, tret;
3072 = resolve_asm_operand_names (ASM_STRING (expr), ASM_OUTPUTS (expr),
3076 for (i = 0, link = ASM_OUTPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3078 oconstraints[i] = constraint
3079 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3081 parse_output_constraint (&constraint, i, 0, 0,
3082 &allows_mem, &allows_reg, &is_inout);
3084 if (!allows_reg && allows_mem)
3085 lang_hooks.mark_addressable (TREE_VALUE (link));
3087 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3088 is_inout ? is_gimple_min_lval : is_gimple_lvalue,
3089 fb_lvalue | fb_mayfail);
3090 if (tret == GS_ERROR)
3092 error ("invalid lvalue in asm output %d", i);
3098 /* An input/output operand. To give the optimizers more
3099 flexibility, split it into separate input and output
3103 size_t constraint_len = strlen (constraint);
3105 /* Turn the in/out constraint into an output constraint. */
3106 char *p = xstrdup (constraint);
3108 TREE_VALUE (TREE_PURPOSE (link)) = build_string (constraint_len, p);
3111 /* And add a matching input constraint. */
3114 sprintf (buf, "%d", i);
3115 input = build_string (strlen (buf), buf);
3118 input = build_string (constraint_len - 1, constraint + 1);
3119 input = build_tree_list (build_tree_list (NULL_TREE, input),
3120 unshare_expr (TREE_VALUE (link)));
3121 ASM_INPUTS (expr) = chainon (ASM_INPUTS (expr), input);
3125 for (link = ASM_INPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3128 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3129 parse_input_constraint (&constraint, 0, 0, noutputs, 0,
3130 oconstraints, &allows_mem, &allows_reg);
3132 /* If the operand is a memory input, it should be an lvalue. */
3133 if (!allows_reg && allows_mem)
3135 lang_hooks.mark_addressable (TREE_VALUE (link));
3136 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3137 is_gimple_lvalue, fb_lvalue | fb_mayfail);
3138 if (tret == GS_ERROR)
3140 error ("memory input %d is not directly addressable", i);
3146 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3147 is_gimple_val, fb_rvalue);
3148 if (tret == GS_ERROR)
3156 /* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding
3157 WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
3158 gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
3159 return to this function.
3161 FIXME should we complexify the prequeue handling instead? Or use flags
3162 for all the cleanups and let the optimizer tighten them up? The current
3163 code seems pretty fragile; it will break on a cleanup within any
3164 non-conditional nesting. But any such nesting would be broken, anyway;
3165 we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
3166 and continues out of it. We can do that at the RTL level, though, so
3167 having an optimizer to tighten up try/finally regions would be a Good
3170 static enum gimplify_status
3171 gimplify_cleanup_point_expr (tree *expr_p, tree *pre_p)
3173 tree_stmt_iterator iter;
3176 tree temp = voidify_wrapper_expr (*expr_p, NULL);
3178 /* We only care about the number of conditions between the innermost
3179 CLEANUP_POINT_EXPR and the cleanup. So save and reset the count. */
3180 int old_conds = gimplify_ctxp->conditions;
3181 gimplify_ctxp->conditions = 0;
3183 body = TREE_OPERAND (*expr_p, 0);
3184 gimplify_to_stmt_list (&body);
3186 gimplify_ctxp->conditions = old_conds;
3188 for (iter = tsi_start (body); !tsi_end_p (iter); )
3190 tree *wce_p = tsi_stmt_ptr (iter);
3193 if (TREE_CODE (wce) == WITH_CLEANUP_EXPR)
3195 if (tsi_one_before_end_p (iter))
3197 tsi_link_before (&iter, TREE_OPERAND (wce, 0), TSI_SAME_STMT);
3205 sl = tsi_split_statement_list_after (&iter);
3206 tfe = build (TRY_FINALLY_EXPR, void_type_node, sl, NULL_TREE);
3207 append_to_statement_list (TREE_OPERAND (wce, 0),
3208 &TREE_OPERAND (tfe, 1));
3210 iter = tsi_start (sl);
3220 append_to_statement_list (body, pre_p);
3230 /* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP
3231 is the cleanup action required. */
3234 gimple_push_cleanup (tree var, tree cleanup, tree *pre_p)
3238 /* Errors can result in improperly nested cleanups. Which results in
3239 confusion when trying to resolve the WITH_CLEANUP_EXPR. */
3240 if (errorcount || sorrycount)
3243 if (gimple_conditional_context ())
3245 /* If we're in a conditional context, this is more complex. We only
3246 want to run the cleanup if we actually ran the initialization that
3247 necessitates it, but we want to run it after the end of the
3248 conditional context. So we wrap the try/finally around the
3249 condition and use a flag to determine whether or not to actually
3250 run the destructor. Thus
3254 becomes (approximately)
3258 if (test) { A::A(temp); flag = 1; val = f(temp); }
3261 if (flag) A::~A(temp);
3266 tree flag = create_tmp_var (boolean_type_node, "cleanup");
3267 tree ffalse = build (MODIFY_EXPR, void_type_node, flag,
3268 boolean_false_node);
3269 tree ftrue = build (MODIFY_EXPR, void_type_node, flag,
3271 cleanup = build (COND_EXPR, void_type_node, flag, cleanup, NULL);
3272 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3273 append_to_statement_list (ffalse, &gimplify_ctxp->conditional_cleanups);
3274 append_to_statement_list (wce, &gimplify_ctxp->conditional_cleanups);
3275 append_to_statement_list (ftrue, pre_p);
3277 /* Because of this manipulation, and the EH edges that jump
3278 threading cannot redirect, the temporary (VAR) will appear
3279 to be used uninitialized. Don't warn. */
3280 TREE_NO_WARNING (var) = 1;
3284 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3285 append_to_statement_list (wce, pre_p);
3288 gimplify_stmt (&TREE_OPERAND (wce, 0));
3291 /* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */
3293 static enum gimplify_status
3294 gimplify_target_expr (tree *expr_p, tree *pre_p, tree *post_p)
3296 tree targ = *expr_p;
3297 tree temp = TARGET_EXPR_SLOT (targ);
3298 tree init = TARGET_EXPR_INITIAL (targ);
3299 enum gimplify_status ret;
3303 /* TARGET_EXPR temps aren't part of the enclosing block, so add it
3304 to the temps list. */
3305 gimple_add_tmp_var (temp);
3307 /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
3308 expression is supposed to initialize the slot. */
3309 if (VOID_TYPE_P (TREE_TYPE (init)))
3310 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, fb_none);
3313 /* Special handling for BIND_EXPR can result in fewer temps. */
3315 if (TREE_CODE (init) == BIND_EXPR)
3316 gimplify_bind_expr (&init, temp, pre_p);
3319 init = build (MODIFY_EXPR, void_type_node, temp, init);
3320 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt,
3324 if (ret == GS_ERROR)
3326 append_to_statement_list (init, pre_p);
3328 /* If needed, push the cleanup for the temp. */
3329 if (TARGET_EXPR_CLEANUP (targ))
3331 gimplify_stmt (&TARGET_EXPR_CLEANUP (targ));
3332 gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ), pre_p);
3335 /* Only expand this once. */
3336 TREE_OPERAND (targ, 3) = init;
3337 TARGET_EXPR_INITIAL (targ) = NULL_TREE;
3339 else if (!DECL_SEEN_IN_BIND_EXPR_P (temp))
3340 /* We should have expanded this before. */
3347 /* Gimplification of expression trees. */
3349 /* Gimplify an expression which appears at statement context; usually, this
3350 means replacing it with a suitably gimple STATEMENT_LIST. */
3353 gimplify_stmt (tree *stmt_p)
3355 gimplify_expr (stmt_p, NULL, NULL, is_gimple_stmt, fb_none);
3358 /* Similarly, but force the result to be a STATEMENT_LIST. */
3361 gimplify_to_stmt_list (tree *stmt_p)
3363 gimplify_stmt (stmt_p);
3365 *stmt_p = alloc_stmt_list ();
3366 else if (TREE_CODE (*stmt_p) != STATEMENT_LIST)
3369 *stmt_p = alloc_stmt_list ();
3370 append_to_statement_list (t, stmt_p);
3375 /* Gimplifies the expression tree pointed by EXPR_P. Return 0 if
3376 gimplification failed.
3378 PRE_P points to the list where side effects that must happen before
3379 EXPR should be stored.
3381 POST_P points to the list where side effects that must happen after
3382 EXPR should be stored, or NULL if there is no suitable list. In
3383 that case, we copy the result to a temporary, emit the
3384 post-effects, and then return the temporary.
3386 GIMPLE_TEST_F points to a function that takes a tree T and
3387 returns nonzero if T is in the GIMPLE form requested by the
3388 caller. The GIMPLE predicates are in tree-gimple.c.
3390 This test is used twice. Before gimplification, the test is
3391 invoked to determine whether *EXPR_P is already gimple enough. If
3392 that fails, *EXPR_P is gimplified according to its code and
3393 GIMPLE_TEST_F is called again. If the test still fails, then a new
3394 temporary variable is created and assigned the value of the
3395 gimplified expression.
3397 FALLBACK tells the function what sort of a temporary we want. If the 1
3398 bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK.
3399 If both are set, either is OK, but an lvalue is preferable.
3401 The return value is either GS_ERROR or GS_ALL_DONE, since this function
3402 iterates until solution. */
3404 enum gimplify_status
3405 gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
3406 bool (* gimple_test_f) (tree), fallback_t fallback)
3409 tree internal_pre = NULL_TREE;
3410 tree internal_post = NULL_TREE;
3412 int is_statement = (pre_p == NULL);
3413 location_t saved_location;
3414 enum gimplify_status ret;
3416 save_expr = *expr_p;
3417 if (save_expr == NULL_TREE)
3420 /* We used to check the predicate here and return immediately if it
3421 succeeds. This is wrong; the design is for gimplification to be
3422 idempotent, and for the predicates to only test for valid forms, not
3423 whether they are fully simplified. */
3425 /* Set up our internal queues if needed. */
3427 pre_p = &internal_pre;
3429 post_p = &internal_post;
3431 saved_location = input_location;
3432 if (save_expr != error_mark_node
3433 && EXPR_HAS_LOCATION (*expr_p))
3434 input_location = EXPR_LOCATION (*expr_p);
3436 /* Loop over the specific gimplifiers until the toplevel node
3437 remains the same. */
3440 /* Strip away as many useless type conversions as possible
3442 STRIP_USELESS_TYPE_CONVERSION (*expr_p);
3444 /* Remember the expr. */
3445 save_expr = *expr_p;
3447 /* Die, die, die, my darling. */
3448 if (save_expr == error_mark_node
3449 || (TREE_TYPE (save_expr)
3450 && TREE_TYPE (save_expr) == error_mark_node))
3456 /* Do any language-specific gimplification. */
3457 ret = lang_hooks.gimplify_expr (expr_p, pre_p, post_p);
3460 if (*expr_p == NULL_TREE)
3462 if (*expr_p != save_expr)
3465 else if (ret != GS_UNHANDLED)
3469 switch (TREE_CODE (*expr_p))
3471 /* First deal with the special cases. */
3473 case POSTINCREMENT_EXPR:
3474 case POSTDECREMENT_EXPR:
3475 case PREINCREMENT_EXPR:
3476 case PREDECREMENT_EXPR:
3477 ret = gimplify_self_mod_expr (expr_p, pre_p, post_p,
3478 fallback != fb_none);
3482 case ARRAY_RANGE_REF:
3486 case VIEW_CONVERT_EXPR:
3487 ret = gimplify_compound_lval (expr_p, pre_p, post_p,
3488 fallback ? fallback : fb_rvalue);
3492 ret = gimplify_cond_expr (expr_p, pre_p, NULL_TREE);
3496 ret = gimplify_call_expr (expr_p, pre_p, fallback != fb_none);
3503 ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none);
3508 ret = gimplify_modify_expr (expr_p, pre_p, post_p,
3509 fallback != fb_none);
3512 case TRUTH_ANDIF_EXPR:
3513 case TRUTH_ORIF_EXPR:
3514 ret = gimplify_boolean_expr (expr_p);
3517 case TRUTH_NOT_EXPR:
3518 TREE_OPERAND (*expr_p, 0)
3519 = gimple_boolify (TREE_OPERAND (*expr_p, 0));
3520 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3521 is_gimple_val, fb_rvalue);
3522 recalculate_side_effects (*expr_p);
3526 ret = gimplify_addr_expr (expr_p, pre_p, post_p);
3530 ret = gimplify_va_arg_expr (expr_p, pre_p, post_p);
3535 if (IS_EMPTY_STMT (*expr_p))
3541 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
3542 || fallback == fb_none)
3544 /* Just strip a conversion to void (or in void context) and
3546 *expr_p = TREE_OPERAND (*expr_p, 0);
3550 ret = gimplify_conversion (expr_p);
3551 if (ret == GS_ERROR)
3553 if (*expr_p != save_expr)
3557 case FIX_TRUNC_EXPR:
3559 case FIX_FLOOR_EXPR:
3560 case FIX_ROUND_EXPR:
3561 /* unary_expr: ... | '(' cast ')' val | ... */
3562 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3563 is_gimple_val, fb_rvalue);
3564 recalculate_side_effects (*expr_p);
3568 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3569 is_gimple_reg, fb_rvalue);
3570 recalculate_side_effects (*expr_p);
3573 /* Constants need not be gimplified. */
3583 *expr_p = DECL_INITIAL (*expr_p);
3587 ret = gimplify_decl_expr (expr_p);
3591 /* FIXME make this a decl. */
3596 ret = gimplify_bind_expr (expr_p, NULL, pre_p);
3600 ret = gimplify_loop_expr (expr_p, pre_p);
3604 ret = gimplify_switch_expr (expr_p, pre_p);
3607 case LABELED_BLOCK_EXPR:
3608 ret = gimplify_labeled_block_expr (expr_p);
3611 case EXIT_BLOCK_EXPR:
3612 ret = gimplify_exit_block_expr (expr_p);
3616 ret = gimplify_exit_expr (expr_p);
3620 /* If the target is not LABEL, then it is a computed jump
3621 and the target needs to be gimplified. */
3622 if (TREE_CODE (GOTO_DESTINATION (*expr_p)) != LABEL_DECL)
3623 ret = gimplify_expr (&GOTO_DESTINATION (*expr_p), pre_p,
3624 NULL, is_gimple_val, fb_rvalue);
3629 #ifdef ENABLE_CHECKING
3630 if (decl_function_context (LABEL_EXPR_LABEL (*expr_p)) != current_function_decl)
3635 case CASE_LABEL_EXPR:
3636 ret = gimplify_case_label_expr (expr_p);
3640 ret = gimplify_return_expr (*expr_p, pre_p);
3644 /* Don't reduce this in place; let gimplify_init_constructor work its
3645 magic. Buf if we're just elaborating this for side effects, just
3646 gimplify any element that has side-effects. */
3647 if (fallback == fb_none)
3649 for (tmp = CONSTRUCTOR_ELTS (*expr_p); tmp;
3650 tmp = TREE_CHAIN (tmp))
3651 if (TREE_SIDE_EFFECTS (TREE_VALUE (tmp)))
3652 gimplify_expr (&TREE_VALUE (tmp), pre_p, post_p,
3653 gimple_test_f, fallback);
3655 *expr_p = NULL_TREE;
3661 /* The following are special cases that are not handled by the
3662 original GIMPLE grammar. */
3664 /* SAVE_EXPR nodes are converted into a GIMPLE identifier and
3667 ret = gimplify_save_expr (expr_p, pre_p, post_p);
3672 enum gimplify_status r0, r1, r2;
3674 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3675 is_gimple_lvalue, fb_either);
3676 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3677 is_gimple_val, fb_rvalue);
3678 r2 = gimplify_expr (&TREE_OPERAND (*expr_p, 2), pre_p, post_p,
3679 is_gimple_val, fb_rvalue);
3680 recalculate_side_effects (*expr_p);
3682 ret = MIN (r0, MIN (r1, r2));
3686 case NON_LVALUE_EXPR:
3687 /* This should have been stripped above. */
3692 ret = gimplify_asm_expr (expr_p, pre_p, post_p);
3695 case TRY_FINALLY_EXPR:
3696 case TRY_CATCH_EXPR:
3697 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 0));
3698 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 1));
3702 case CLEANUP_POINT_EXPR:
3703 ret = gimplify_cleanup_point_expr (expr_p, pre_p);
3707 ret = gimplify_target_expr (expr_p, pre_p, post_p);
3711 gimplify_to_stmt_list (&CATCH_BODY (*expr_p));
3715 case EH_FILTER_EXPR:
3716 gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p));
3722 enum gimplify_status r0, r1;
3723 r0 = gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p), pre_p, post_p,
3724 is_gimple_val, fb_rvalue);
3725 r1 = gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p), pre_p, post_p,
3726 is_gimple_val, fb_rvalue);
3733 ret = gimplify_minimax_expr (expr_p, pre_p, post_p);
3737 /* We get here when taking the address of a label. We mark
3738 the label as "forced"; meaning it can never be removed and
3739 it is a potential target for any computed goto. */
3740 FORCED_LABEL (*expr_p) = 1;
3744 case STATEMENT_LIST:
3745 ret = gimplify_statement_list (expr_p);
3748 case WITH_SIZE_EXPR:
3750 enum gimplify_status r0, r1;
3751 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3752 post_p == &internal_post ? NULL : post_p,
3753 gimple_test_f, fallback);
3754 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3755 is_gimple_val, fb_rvalue);
3760 /* ??? If this is a local variable, and it has not been seen in any
3761 outer BIND_EXPR, then it's probably the result of a duplicate
3762 declaration, for which we've already issued an error. It would
3763 be really nice if the front end wouldn't leak these at all.
3764 Currently the only known culprit is C++ destructors, as seen
3765 in g++.old-deja/g++.jason/binding.C. */
3767 if (!TREE_STATIC (tmp) && !DECL_EXTERNAL (tmp)
3768 && decl_function_context (tmp) == current_function_decl
3769 && !DECL_SEEN_IN_BIND_EXPR_P (tmp))
3771 #ifdef ENABLE_CHECKING
3772 if (!errorcount && !sorrycount)
3782 /* Allow callbacks into the gimplifier during optimization. */
3787 /* If this is a comparison of objects of aggregate type, handle
3788 it specially (by converting to a call to memcmp). It would be
3789 nice to only have to do this for variable-sized objects, but
3790 then we'd have to allow the same nest of reference nodes we
3791 allow for MODIFY_EXPR and that's too complex. */
3792 if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3793 && (AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 1)))))
3794 ret = gimplify_variable_sized_compare (expr_p);
3796 /* If *EXPR_P does not need to be special-cased, handle it
3797 according to its class. */
3798 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '1')
3799 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3800 post_p, is_gimple_val, fb_rvalue);
3801 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '2'
3802 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3803 || TREE_CODE (*expr_p) == TRUTH_AND_EXPR
3804 || TREE_CODE (*expr_p) == TRUTH_OR_EXPR
3805 || TREE_CODE (*expr_p) == TRUTH_XOR_EXPR)
3807 enum gimplify_status r0, r1;
3809 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3810 post_p, is_gimple_val, fb_rvalue);
3811 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p,
3812 post_p, is_gimple_val, fb_rvalue);
3816 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'd'
3817 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'c')
3823 /* Fail if we don't know how to handle this tree code. */
3826 recalculate_side_effects (*expr_p);
3830 /* If we replaced *expr_p, gimplify again. */
3831 if (ret == GS_OK && (*expr_p == NULL || *expr_p == save_expr))
3834 while (ret == GS_OK);
3836 /* If we encountered an error_mark somewhere nested inside, either
3837 stub out the statement or propagate the error back out. */
3838 if (ret == GS_ERROR)
3845 #ifdef ENABLE_CHECKING
3846 /* This was only valid as a return value from the langhook, which
3847 we handled. Make sure it doesn't escape from any other context. */
3848 if (ret == GS_UNHANDLED)
3852 if (fallback == fb_none && *expr_p && !is_gimple_stmt (*expr_p))
3854 /* We aren't looking for a value, and we don't have a valid
3855 statement. If it doesn't have side-effects, throw it away. */
3856 if (!TREE_SIDE_EFFECTS (*expr_p))
3858 else if (!TREE_THIS_VOLATILE (*expr_p))
3860 /* This is probably a _REF that contains something nested that
3861 has side effects. Recurse through the operands to find it. */
3862 enum tree_code code = TREE_CODE (*expr_p);
3864 if (code == COMPONENT_REF
3865 || code == REALPART_EXPR || code == IMAGPART_EXPR)
3866 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3867 gimple_test_f, fallback);
3868 else if (code == ARRAY_REF || code == ARRAY_RANGE_REF)
3870 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3871 gimple_test_f, fallback);
3872 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3873 gimple_test_f, fallback);
3876 /* Anything else with side-effects
3877 must be converted to a valid statement before we get here. */
3882 else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p)))
3884 /* Historically, the compiler has treated a bare
3885 reference to a volatile lvalue as forcing a load. */
3886 tree tmp = create_tmp_var (TREE_TYPE (*expr_p), "vol");
3887 *expr_p = build (MODIFY_EXPR, TREE_TYPE (tmp), tmp, *expr_p);
3890 /* We can't do anything useful with a volatile reference to
3891 incomplete type, so just throw it away. */
3895 /* If we are gimplifying at the statement level, we're done. Tack
3896 everything together and replace the original statement with the
3898 if (fallback == fb_none || is_statement)
3900 if (internal_pre || internal_post)
3902 append_to_statement_list (*expr_p, &internal_pre);
3903 append_to_statement_list (internal_post, &internal_pre);
3904 annotate_all_with_locus (&internal_pre, input_location);
3905 *expr_p = internal_pre;
3909 else if (TREE_CODE (*expr_p) == STATEMENT_LIST)
3910 annotate_all_with_locus (expr_p, input_location);
3912 annotate_one_with_locus (*expr_p, input_location);
3916 /* Otherwise we're gimplifying a subexpression, so the resulting value is
3919 /* If it's sufficiently simple already, we're done. Unless we are
3920 handling some post-effects internally; if that's the case, we need to
3921 copy into a temp before adding the post-effects to the tree. */
3922 if (!internal_post && (*gimple_test_f) (*expr_p))
3925 /* Otherwise, we need to create a new temporary for the gimplified
3928 /* We can't return an lvalue if we have an internal postqueue. The
3929 object the lvalue refers to would (probably) be modified by the
3930 postqueue; we need to copy the value out first, which means an
3932 if ((fallback & fb_lvalue) && !internal_post
3933 && is_gimple_addr_expr_arg (*expr_p))
3935 /* An lvalue will do. Take the address of the expression, store it
3936 in a temporary, and replace the expression with an INDIRECT_REF of
3938 tmp = build_fold_addr_expr (*expr_p);
3939 gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue);
3940 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp);
3942 else if ((fallback & fb_rvalue) && is_gimple_tmp_rhs (*expr_p))
3944 #if defined ENABLE_CHECKING
3945 if (VOID_TYPE_P (TREE_TYPE (*expr_p)))
3949 /* An rvalue will do. Assign the gimplified expression into a new
3950 temporary TMP and replace the original expression with TMP. */
3952 if (internal_post || (fallback & fb_lvalue))
3953 /* The postqueue might change the value of the expression between
3954 the initialization and use of the temporary, so we can't use a
3955 formal temp. FIXME do we care? */
3956 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
3958 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
3960 else if (fallback & fb_mayfail)
3962 /* If this is an asm statement, and the user asked for the impossible,
3963 don't abort. Fail and let gimplify_asm_expr issue an error. */
3969 fprintf (stderr, "gimplification failed:\n");
3970 print_generic_expr (stderr, *expr_p, 0);
3971 debug_tree (*expr_p);
3975 #if defined ENABLE_CHECKING
3976 /* Make sure the temporary matches our predicate. */
3977 if (!(*gimple_test_f) (*expr_p))
3983 annotate_all_with_locus (&internal_post, input_location);
3984 append_to_statement_list (internal_post, pre_p);
3988 input_location = saved_location;
3992 /* Look through TYPE for variable-sized objects and gimplify each such
3993 size that we find. Add to LIST_P any statements generated. */
3996 gimplify_type_sizes (tree type, tree *list_p)
4000 switch (TREE_CODE (type))
4010 gimplify_one_sizepos (&TYPE_MIN_VALUE (type), list_p);
4011 gimplify_one_sizepos (&TYPE_MAX_VALUE (type), list_p);
4015 /* These anonymous types don't have declarations, so handle them here. */
4016 gimplify_type_sizes (TYPE_DOMAIN (type), list_p);
4021 case QUAL_UNION_TYPE:
4022 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4023 if (TREE_CODE (field) == FIELD_DECL)
4024 gimplify_one_sizepos (&DECL_FIELD_OFFSET (field), list_p);
4031 gimplify_one_sizepos (&TYPE_SIZE (type), list_p);
4032 gimplify_one_sizepos (&TYPE_SIZE_UNIT (type), list_p);
4035 /* Subroutine of the above to gimplify one size or position, *EXPR_P.
4036 We add any required statements to STMT_P. */
4039 gimplify_one_sizepos (tree *expr_p, tree *stmt_p)
4041 /* We don't do anything if the value isn't there, is constant, or contains
4042 A PLACEHOLDER_EXPR. We also don't want to do anything if it's already
4043 a VAR_DECL. If it's a VAR_DECL from another function, the gimplfier
4044 will want to replace it with a new variable, but that will cause problems
4045 if this type is from outside the function. It's OK to have that here. */
4046 if (*expr_p == NULL_TREE || TREE_CONSTANT (*expr_p)
4047 || TREE_CODE (*expr_p) == VAR_DECL
4048 || CONTAINS_PLACEHOLDER_P (*expr_p))
4051 gimplify_expr (expr_p, stmt_p, NULL, is_gimple_val, fb_rvalue);
4054 #ifdef ENABLE_CHECKING
4055 /* Compare types A and B for a "close enough" match. */
4058 cpt_same_type (tree a, tree b)
4060 if (lang_hooks.types_compatible_p (a, b))
4063 /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't
4064 link them together. This routine is intended to catch type errors
4065 that will affect the optimizers, and the optimizers don't add new
4066 dereferences of function pointers, so ignore it. */
4067 if ((TREE_CODE (a) == FUNCTION_TYPE || TREE_CODE (a) == METHOD_TYPE)
4068 && (TREE_CODE (b) == FUNCTION_TYPE || TREE_CODE (b) == METHOD_TYPE))
4071 /* ??? The C FE pushes type qualifiers after the fact into the type of
4072 the element from the type of the array. See build_unary_op's handling
4073 of ADDR_EXPR. This seems wrong -- if we were going to do this, we
4074 should have done it when creating the variable in the first place.
4075 Alternately, why aren't the two array types made variants? */
4076 if (TREE_CODE (a) == ARRAY_TYPE && TREE_CODE (b) == ARRAY_TYPE)
4077 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4079 /* And because of those, we have to recurse down through pointers. */
4080 if (POINTER_TYPE_P (a) && POINTER_TYPE_P (b))
4081 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4086 /* Check for some cases of the front end missing cast expressions.
4087 The type of a dereference should correspond to the pointer type;
4088 similarly the type of an address should match its object. */
4091 check_pointer_types_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
4092 void *data ATTRIBUTE_UNUSED)
4095 tree ptype, otype, dtype;
4097 switch (TREE_CODE (t))
4101 otype = TREE_TYPE (t);
4102 ptype = TREE_TYPE (TREE_OPERAND (t, 0));
4103 dtype = TREE_TYPE (ptype);
4104 if (!cpt_same_type (otype, dtype))
4109 ptype = TREE_TYPE (t);
4110 otype = TREE_TYPE (TREE_OPERAND (t, 0));
4111 dtype = TREE_TYPE (ptype);
4112 if (!cpt_same_type (otype, dtype))
4114 /* &array is allowed to produce a pointer to the element, rather than
4115 a pointer to the array type. We must allow this in order to
4116 properly represent assigning the address of an array in C into
4117 pointer to the element type. */
4118 if (TREE_CODE (otype) == ARRAY_TYPE
4119 && POINTER_TYPE_P (ptype)
4120 && cpt_same_type (TREE_TYPE (otype), dtype))
4135 /* Gimplify the body of statements pointed by BODY_P. FNDECL is the
4136 function decl containing BODY. */
4139 gimplify_body (tree *body_p, tree fndecl)
4141 location_t saved_location = input_location;
4144 timevar_push (TV_TREE_GIMPLIFY);
4145 push_gimplify_context ();
4147 /* Unshare most shared trees in the body and in that of any nested functions.
4148 It would seem we don't have to do this for nested functions because
4149 they are supposed to be output and then the outer function gimplified
4150 first, but the g++ front end doesn't always do it that way. */
4151 unshare_body (body_p, fndecl);
4152 unvisit_body (body_p, fndecl);
4154 /* Make sure input_location isn't set to something wierd. */
4155 input_location = DECL_SOURCE_LOCATION (fndecl);
4157 /* Gimplify the function's body. */
4158 gimplify_stmt (body_p);
4161 /* Unshare again, in case gimplification was sloppy. */
4162 unshare_all_trees (body);
4165 body = alloc_stmt_list ();
4166 else if (TREE_CODE (body) == STATEMENT_LIST)
4168 tree t = expr_only (*body_p);
4173 /* If there isn't an outer BIND_EXPR, add one. */
4174 if (TREE_CODE (body) != BIND_EXPR)
4176 tree b = build (BIND_EXPR, void_type_node, NULL_TREE,
4177 NULL_TREE, NULL_TREE);
4178 TREE_SIDE_EFFECTS (b) = 1;
4179 append_to_statement_list_force (body, &BIND_EXPR_BODY (b));
4184 pop_gimplify_context (body);
4186 #ifdef ENABLE_CHECKING
4187 walk_tree (body_p, check_pointer_types_r, NULL, NULL);
4190 timevar_pop (TV_TREE_GIMPLIFY);
4191 input_location = saved_location;
4194 /* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL
4195 node for the function we want to gimplify. */
4198 gimplify_function_tree (tree fndecl)
4202 oldfn = current_function_decl;
4203 current_function_decl = fndecl;
4205 gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl);
4207 /* If we're instrumenting function entry/exit, then prepend the call to
4208 the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
4209 catch the exit hook. */
4210 /* ??? Add some way to ignore exceptions for this TFE. */
4211 if (flag_instrument_function_entry_exit
4212 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl))
4216 tf = build (TRY_FINALLY_EXPR, void_type_node, NULL, NULL);
4217 TREE_SIDE_EFFECTS (tf) = 1;
4218 x = DECL_SAVED_TREE (fndecl);
4219 append_to_statement_list (x, &TREE_OPERAND (tf, 0));
4220 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_EXIT];
4221 x = build_function_call_expr (x, NULL);
4222 append_to_statement_list (x, &TREE_OPERAND (tf, 1));
4224 bind = build (BIND_EXPR, void_type_node, NULL, NULL, NULL);
4225 TREE_SIDE_EFFECTS (bind) = 1;
4226 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_ENTER];
4227 x = build_function_call_expr (x, NULL);
4228 append_to_statement_list (x, &BIND_EXPR_BODY (bind));
4229 append_to_statement_list (tf, &BIND_EXPR_BODY (bind));
4231 DECL_SAVED_TREE (fndecl) = bind;
4234 current_function_decl = oldfn;
4237 #include "gt-gimplify.h"