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 /* Returns true if T is a GIMPLE temporary variable, false otherwise. */
482 is_gimple_tmp_var (tree t)
484 /* FIXME this could trigger for other local artificials, too. */
485 return (TREE_CODE (t) == VAR_DECL && DECL_ARTIFICIAL (t)
486 && !TREE_STATIC (t) && !DECL_EXTERNAL (t));
489 /* Declares all the variables in VARS in SCOPE. */
492 declare_tmp_vars (tree vars, tree scope)
499 /* C99 mode puts the default 'return 0;' for main outside the outer
500 braces. So drill down until we find an actual scope. */
501 while (TREE_CODE (scope) == COMPOUND_EXPR)
502 scope = TREE_OPERAND (scope, 0);
504 if (TREE_CODE (scope) != BIND_EXPR)
507 temps = nreverse (last);
508 TREE_CHAIN (last) = BIND_EXPR_VARS (scope);
509 BIND_EXPR_VARS (scope) = temps;
514 gimple_add_tmp_var (tree tmp)
516 if (TREE_CHAIN (tmp) || DECL_SEEN_IN_BIND_EXPR_P (tmp))
519 DECL_CONTEXT (tmp) = current_function_decl;
520 DECL_SEEN_IN_BIND_EXPR_P (tmp) = 1;
524 TREE_CHAIN (tmp) = gimplify_ctxp->temps;
525 gimplify_ctxp->temps = tmp;
530 declare_tmp_vars (tmp, DECL_SAVED_TREE (current_function_decl));
533 /* Determines whether to assign a locus to the statement STMT. */
536 should_carry_locus_p (tree stmt)
538 /* Don't emit a line note for a label. We particularly don't want to
539 emit one for the break label, since it doesn't actually correspond
540 to the beginning of the loop/switch. */
541 if (TREE_CODE (stmt) == LABEL_EXPR)
544 /* Do not annotate empty statements, since it confuses gcov. */
545 if (!TREE_SIDE_EFFECTS (stmt))
552 annotate_one_with_locus (tree t, location_t locus)
554 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (t)))
555 && ! EXPR_HAS_LOCATION (t)
556 && should_carry_locus_p (t))
557 SET_EXPR_LOCATION (t, locus);
561 annotate_all_with_locus (tree *stmt_p, location_t locus)
563 tree_stmt_iterator i;
568 for (i = tsi_start (*stmt_p); !tsi_end_p (i); tsi_next (&i))
570 tree t = tsi_stmt (i);
572 #ifdef ENABLE_CHECKING
573 /* Assuming we've already been gimplified, we shouldn't
574 see nested chaining constructs anymore. */
575 if (TREE_CODE (t) == STATEMENT_LIST
576 || TREE_CODE (t) == COMPOUND_EXPR)
580 annotate_one_with_locus (t, locus);
584 /* Similar to copy_tree_r() but do not copy SAVE_EXPR or TARGET_EXPR nodes.
585 These nodes model computations that should only be done once. If we
586 were to unshare something like SAVE_EXPR(i++), the gimplification
587 process would create wrong code. */
590 mostly_copy_tree_r (tree *tp, int *walk_subtrees, void *data)
592 enum tree_code code = TREE_CODE (*tp);
593 /* Don't unshare types, decls, constants and SAVE_EXPR nodes. */
594 if (TREE_CODE_CLASS (code) == 't'
595 || TREE_CODE_CLASS (code) == 'd'
596 || TREE_CODE_CLASS (code) == 'c'
597 || code == SAVE_EXPR || code == TARGET_EXPR
598 /* We can't do anything sensible with a BLOCK used as an expression,
599 but we also can't abort when we see it because of non-expression
600 uses. So just avert our eyes and cross our fingers. Silly Java. */
603 else if (code == BIND_EXPR)
606 copy_tree_r (tp, walk_subtrees, data);
611 /* Callback for walk_tree to unshare most of the shared trees rooted at
612 *TP. If *TP has been visited already (i.e., TREE_VISITED (*TP) == 1),
613 then *TP is deep copied by calling copy_tree_r.
615 This unshares the same trees as copy_tree_r with the exception of
616 SAVE_EXPR nodes. These nodes model computations that should only be
617 done once. If we were to unshare something like SAVE_EXPR(i++), the
618 gimplification process would create wrong code. */
621 copy_if_shared_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
622 void *data ATTRIBUTE_UNUSED)
625 enum tree_code code = TREE_CODE (t);
627 /* Skip types, decls, and constants. But we do want to look at their
628 types and the bounds of types. Mark them as visited so we properly
629 unmark their subtrees on the unmark pass. If we've already seen them,
630 don't look down further. */
631 if (TREE_CODE_CLASS (code) == 't'
632 || TREE_CODE_CLASS (code) == 'd'
633 || TREE_CODE_CLASS (code) == 'c')
635 if (TREE_VISITED (t))
638 TREE_VISITED (t) = 1;
641 /* If this node has been visited already, unshare it and don't look
643 else if (TREE_VISITED (t))
645 walk_tree (tp, mostly_copy_tree_r, NULL, NULL);
649 /* Otherwise, mark the tree as visited and keep looking. */
651 TREE_VISITED (t) = 1;
657 unmark_visited_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
658 void *data ATTRIBUTE_UNUSED)
660 if (TREE_VISITED (*tp))
661 TREE_VISITED (*tp) = 0;
668 /* Unshare all the trees in BODY_P, a pointer into the body of FNDECL, and the
669 bodies of any nested functions if we are unsharing the entire body of
673 unshare_body (tree *body_p, tree fndecl)
675 struct cgraph_node *cgn = cgraph_node (fndecl);
677 walk_tree (body_p, copy_if_shared_r, NULL, NULL);
678 if (body_p == &DECL_SAVED_TREE (fndecl))
679 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
680 unshare_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
683 /* Likewise, but mark all trees as not visited. */
686 unvisit_body (tree *body_p, tree fndecl)
688 struct cgraph_node *cgn = cgraph_node (fndecl);
690 walk_tree (body_p, unmark_visited_r, NULL, NULL);
691 if (body_p == &DECL_SAVED_TREE (fndecl))
692 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
693 unvisit_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
696 /* Unshare T and all the trees reached from T via TREE_CHAIN. */
699 unshare_all_trees (tree t)
701 walk_tree (&t, copy_if_shared_r, NULL, NULL);
702 walk_tree (&t, unmark_visited_r, NULL, NULL);
705 /* Unconditionally make an unshared copy of EXPR. This is used when using
706 stored expressions which span multiple functions, such as BINFO_VTABLE,
707 as the normal unsharing process can't tell that they're shared. */
710 unshare_expr (tree expr)
712 walk_tree (&expr, mostly_copy_tree_r, NULL, NULL);
716 /* A terser interface for building a representation of a exception
720 gimple_build_eh_filter (tree body, tree allowed, tree failure)
724 /* FIXME should the allowed types go in TREE_TYPE? */
725 t = build (EH_FILTER_EXPR, void_type_node, allowed, NULL_TREE);
726 append_to_statement_list (failure, &EH_FILTER_FAILURE (t));
728 t = build (TRY_CATCH_EXPR, void_type_node, NULL_TREE, t);
729 append_to_statement_list (body, &TREE_OPERAND (t, 0));
735 /* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
736 contain statements and have a value. Assign its value to a temporary
737 and give it void_type_node. Returns the temporary, or NULL_TREE if
738 WRAPPER was already void. */
741 voidify_wrapper_expr (tree wrapper, tree temp)
743 if (!VOID_TYPE_P (TREE_TYPE (wrapper)))
745 tree *p, sub = wrapper;
748 /* Set p to point to the body of the wrapper. */
749 switch (TREE_CODE (sub))
752 /* For a BIND_EXPR, the body is operand 1. */
753 p = &BIND_EXPR_BODY (sub);
757 p = &TREE_OPERAND (sub, 0);
761 /* Advance to the last statement. Set all container types to void. */
762 if (TREE_CODE (*p) == STATEMENT_LIST)
764 tree_stmt_iterator i = tsi_last (*p);
765 p = tsi_end_p (i) ? NULL : tsi_stmt_ptr (i);
769 for (; TREE_CODE (*p) == COMPOUND_EXPR; p = &TREE_OPERAND (*p, 1))
771 TREE_SIDE_EFFECTS (*p) = 1;
772 TREE_TYPE (*p) = void_type_node;
776 if (p == NULL || IS_EMPTY_STMT (*p))
778 /* Look through exception handling. */
779 else if (TREE_CODE (*p) == TRY_FINALLY_EXPR
780 || TREE_CODE (*p) == TRY_CATCH_EXPR)
785 /* The C++ frontend already did this for us. */
786 else if (TREE_CODE (*p) == INIT_EXPR
787 || TREE_CODE (*p) == TARGET_EXPR)
788 temp = TREE_OPERAND (*p, 0);
789 /* If we're returning a dereference, move the dereference
790 outside the wrapper. */
791 else if (TREE_CODE (*p) == INDIRECT_REF)
793 tree ptr = TREE_OPERAND (*p, 0);
794 temp = create_tmp_var (TREE_TYPE (ptr), "retval");
795 *p = build (MODIFY_EXPR, TREE_TYPE (ptr), temp, ptr);
796 temp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (temp)), temp);
797 /* If this is a BIND_EXPR for a const inline function, it might not
798 have TREE_SIDE_EFFECTS set. That is no longer accurate. */
799 TREE_SIDE_EFFECTS (wrapper) = 1;
804 temp = create_tmp_var (TREE_TYPE (wrapper), "retval");
805 *p = build (MODIFY_EXPR, TREE_TYPE (temp), temp, *p);
806 TREE_SIDE_EFFECTS (wrapper) = 1;
809 TREE_TYPE (wrapper) = void_type_node;
816 /* Prepare calls to builtins to SAVE and RESTORE the stack as well as
817 a temporary through which they communicate. */
820 build_stack_save_restore (tree *save, tree *restore)
822 tree save_call, tmp_var;
825 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_SAVE],
827 tmp_var = create_tmp_var (ptr_type_node, "saved_stack");
829 *save = build (MODIFY_EXPR, ptr_type_node, tmp_var, save_call);
831 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_RESTORE],
832 tree_cons (NULL_TREE, tmp_var, NULL_TREE));
835 /* Gimplify a BIND_EXPR. Just voidify and recurse. */
837 static enum gimplify_status
838 gimplify_bind_expr (tree *expr_p, tree temp, tree *pre_p)
840 tree bind_expr = *expr_p;
841 bool old_save_stack = gimplify_ctxp->save_stack;
844 temp = voidify_wrapper_expr (bind_expr, temp);
846 /* Mark variables seen in this bind expr. */
847 for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t))
848 DECL_SEEN_IN_BIND_EXPR_P (t) = 1;
850 gimple_push_bind_expr (bind_expr);
851 gimplify_ctxp->save_stack = false;
853 gimplify_to_stmt_list (&BIND_EXPR_BODY (bind_expr));
855 if (gimplify_ctxp->save_stack)
857 tree stack_save, stack_restore;
859 /* Save stack on entry and restore it on exit. Add a try_finally
860 block to achieve this. Note that mudflap depends on the
861 format of the emitted code: see mx_register_decls(). */
862 build_stack_save_restore (&stack_save, &stack_restore);
864 t = build (TRY_FINALLY_EXPR, void_type_node,
865 BIND_EXPR_BODY (bind_expr), NULL_TREE);
866 append_to_statement_list (stack_restore, &TREE_OPERAND (t, 1));
868 BIND_EXPR_BODY (bind_expr) = NULL_TREE;
869 append_to_statement_list (stack_save, &BIND_EXPR_BODY (bind_expr));
870 append_to_statement_list (t, &BIND_EXPR_BODY (bind_expr));
873 gimplify_ctxp->save_stack = old_save_stack;
874 gimple_pop_bind_expr ();
879 append_to_statement_list (bind_expr, pre_p);
886 /* Gimplify a RETURN_EXPR. If the expression to be returned is not a
887 GIMPLE value, it is assigned to a new temporary and the statement is
888 re-written to return the temporary.
890 PRE_P points to the list where side effects that must happen before
891 STMT should be stored. */
893 static enum gimplify_status
894 gimplify_return_expr (tree stmt, tree *pre_p)
896 tree ret_expr = TREE_OPERAND (stmt, 0);
897 tree result_decl, result;
899 if (!ret_expr || TREE_CODE (ret_expr) == RESULT_DECL
900 || ret_expr == error_mark_node)
903 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
904 result_decl = NULL_TREE;
907 result_decl = TREE_OPERAND (ret_expr, 0);
908 #ifdef ENABLE_CHECKING
909 if ((TREE_CODE (ret_expr) != MODIFY_EXPR
910 && TREE_CODE (ret_expr) != INIT_EXPR)
911 || TREE_CODE (result_decl) != RESULT_DECL)
916 /* If aggregate_value_p is true, then we can return the bare RESULT_DECL.
917 Recall that aggregate_value_p is FALSE for any aggregate type that is
918 returned in registers. If we're returning values in registers, then
919 we don't want to extend the lifetime of the RESULT_DECL, particularly
920 across another call. In addition, for those aggregates for which
921 hard_function_value generates a PARALLEL, we'll abort during normal
922 expansion of structure assignments; there's special code in expand_return
923 to handle this case that does not exist in expand_expr. */
925 || aggregate_value_p (result_decl, TREE_TYPE (current_function_decl)))
926 result = result_decl;
927 else if (gimplify_ctxp->return_temp)
928 result = gimplify_ctxp->return_temp;
931 result = create_tmp_var (TREE_TYPE (result_decl), NULL);
933 /* ??? With complex control flow (usually involving abnormal edges),
934 we can wind up warning about an uninitialized value for this. Due
935 to how this variable is constructed and initialized, this is never
936 true. Give up and never warn. */
937 TREE_NO_WARNING (result) = 1;
939 gimplify_ctxp->return_temp = result;
942 /* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
943 Then gimplify the whole thing. */
944 if (result != result_decl)
945 TREE_OPERAND (ret_expr, 0) = result;
947 gimplify_and_add (TREE_OPERAND (stmt, 0), pre_p);
949 /* If we didn't use a temporary, then the result is just the result_decl.
950 Otherwise we need a simple copy. This should already be gimple. */
951 if (result == result_decl)
954 ret_expr = build (MODIFY_EXPR, TREE_TYPE (result), result_decl, result);
955 TREE_OPERAND (stmt, 0) = ret_expr;
960 /* Gimplifies a DECL_EXPR node *STMT_P by making any necessary allocation
961 and initialization explicit. */
963 static enum gimplify_status
964 gimplify_decl_expr (tree *stmt_p)
967 tree decl = DECL_EXPR_DECL (stmt);
971 if (TREE_TYPE (decl) == error_mark_node)
974 else if (TREE_CODE (decl) == TYPE_DECL)
975 gimplify_type_sizes (TREE_TYPE (decl), stmt_p);
977 else if (TREE_CODE (decl) == VAR_DECL && !DECL_EXTERNAL (decl))
979 tree init = DECL_INITIAL (decl);
981 if (!TREE_CONSTANT (DECL_SIZE (decl)))
983 /* This is a variable-sized decl. Simplify its size and mark it
984 for deferred expansion. Note that mudflap depends on the format
985 of the emitted code: see mx_register_decls(). */
988 gimplify_type_sizes (TREE_TYPE (decl), stmt_p);
989 gimplify_one_sizepos (&DECL_SIZE (decl), stmt_p);
990 gimplify_one_sizepos (&DECL_SIZE_UNIT (decl), stmt_p);
992 args = tree_cons (NULL, DECL_SIZE_UNIT (decl), NULL);
993 t = build_fold_addr_expr (decl);
994 args = tree_cons (NULL, t, args);
995 t = implicit_built_in_decls[BUILT_IN_STACK_ALLOC];
996 t = build_function_call_expr (t, args);
998 gimplify_and_add (t, stmt_p);
999 DECL_DEFER_OUTPUT (decl) = 1;
1002 if (init && init != error_mark_node)
1004 if (!TREE_STATIC (decl))
1006 DECL_INITIAL (decl) = NULL_TREE;
1007 init = build (MODIFY_EXPR, void_type_node, decl, init);
1008 gimplify_and_add (init, stmt_p);
1011 /* We must still examine initializers for static variables
1012 as they may contain a label address. */
1013 walk_tree (&init, force_labels_r, NULL, NULL);
1016 /* This decl isn't mentioned in the enclosing block, so add it to the
1017 list of temps. FIXME it seems a bit of a kludge to say that
1018 anonymous artificial vars aren't pushed, but everything else is. */
1019 if (DECL_ARTIFICIAL (decl) && DECL_NAME (decl) == NULL_TREE)
1020 gimple_add_tmp_var (decl);
1026 /* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body
1027 and replacing the LOOP_EXPR with goto, but if the loop contains an
1028 EXIT_EXPR, we need to append a label for it to jump to. */
1030 static enum gimplify_status
1031 gimplify_loop_expr (tree *expr_p, tree *pre_p)
1033 tree saved_label = gimplify_ctxp->exit_label;
1034 tree start_label = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
1035 tree jump_stmt = build_and_jump (&LABEL_EXPR_LABEL (start_label));
1037 append_to_statement_list (start_label, pre_p);
1039 gimplify_ctxp->exit_label = NULL_TREE;
1041 gimplify_and_add (LOOP_EXPR_BODY (*expr_p), pre_p);
1043 if (gimplify_ctxp->exit_label)
1045 append_to_statement_list (jump_stmt, pre_p);
1046 *expr_p = build1 (LABEL_EXPR, void_type_node, gimplify_ctxp->exit_label);
1049 *expr_p = jump_stmt;
1051 gimplify_ctxp->exit_label = saved_label;
1056 /* Compare two case labels. Because the front end should already have
1057 made sure that case ranges do not overlap, it is enough to only compare
1058 the CASE_LOW values of each case label. */
1061 compare_case_labels (const void *p1, const void *p2)
1063 tree case1 = *(tree *)p1;
1064 tree case2 = *(tree *)p2;
1066 return tree_int_cst_compare (CASE_LOW (case1), CASE_LOW (case2));
1069 /* Sort the case labels in LABEL_VEC in place in ascending order. */
1072 sort_case_labels (tree label_vec)
1074 size_t len = TREE_VEC_LENGTH (label_vec);
1075 tree default_case = TREE_VEC_ELT (label_vec, len - 1);
1077 if (CASE_LOW (default_case))
1081 /* The last label in the vector should be the default case
1083 for (i = 0; i < len; ++i)
1085 tree t = TREE_VEC_ELT (label_vec, i);
1089 TREE_VEC_ELT (label_vec, i) = TREE_VEC_ELT (label_vec, len - 1);
1090 TREE_VEC_ELT (label_vec, len - 1) = default_case;
1096 qsort (&TREE_VEC_ELT (label_vec, 0), len - 1, sizeof (tree),
1097 compare_case_labels);
1100 /* Gimplify a SWITCH_EXPR, and collect a TREE_VEC of the labels it can
1103 static enum gimplify_status
1104 gimplify_switch_expr (tree *expr_p, tree *pre_p)
1106 tree switch_expr = *expr_p;
1107 enum gimplify_status ret;
1109 ret = gimplify_expr (&SWITCH_COND (switch_expr), pre_p, NULL,
1110 is_gimple_val, fb_rvalue);
1112 if (SWITCH_BODY (switch_expr))
1114 varray_type labels, saved_labels;
1115 tree label_vec, default_case = NULL_TREE;
1118 /* If someone can be bothered to fill in the labels, they can
1119 be bothered to null out the body too. */
1120 if (SWITCH_LABELS (switch_expr))
1123 saved_labels = gimplify_ctxp->case_labels;
1124 VARRAY_TREE_INIT (gimplify_ctxp->case_labels, 8, "case_labels");
1126 gimplify_to_stmt_list (&SWITCH_BODY (switch_expr));
1128 labels = gimplify_ctxp->case_labels;
1129 gimplify_ctxp->case_labels = saved_labels;
1131 len = VARRAY_ACTIVE_SIZE (labels);
1133 for (i = 0; i < len; ++i)
1135 tree t = VARRAY_TREE (labels, i);
1138 /* The default case must be the last label in the list. */
1140 VARRAY_TREE (labels, i) = VARRAY_TREE (labels, len - 1);
1146 label_vec = make_tree_vec (len + 1);
1147 SWITCH_LABELS (*expr_p) = label_vec;
1148 append_to_statement_list (switch_expr, pre_p);
1152 /* If the switch has no default label, add one, so that we jump
1153 around the switch body. */
1154 default_case = build (CASE_LABEL_EXPR, void_type_node, NULL_TREE,
1155 NULL_TREE, create_artificial_label ());
1156 append_to_statement_list (SWITCH_BODY (switch_expr), pre_p);
1157 *expr_p = build (LABEL_EXPR, void_type_node,
1158 CASE_LABEL (default_case));
1161 *expr_p = SWITCH_BODY (switch_expr);
1163 for (i = 0; i < len; ++i)
1164 TREE_VEC_ELT (label_vec, i) = VARRAY_TREE (labels, i);
1165 TREE_VEC_ELT (label_vec, len) = default_case;
1167 sort_case_labels (label_vec);
1169 SWITCH_BODY (switch_expr) = NULL;
1171 else if (!SWITCH_LABELS (switch_expr))
1177 static enum gimplify_status
1178 gimplify_case_label_expr (tree *expr_p)
1180 tree expr = *expr_p;
1181 if (gimplify_ctxp->case_labels)
1182 VARRAY_PUSH_TREE (gimplify_ctxp->case_labels, expr);
1185 *expr_p = build (LABEL_EXPR, void_type_node, CASE_LABEL (expr));
1189 /* Gimplify a LABELED_BLOCK_EXPR into a LABEL_EXPR following
1190 a (possibly empty) body. */
1192 static enum gimplify_status
1193 gimplify_labeled_block_expr (tree *expr_p)
1195 tree body = LABELED_BLOCK_BODY (*expr_p);
1196 tree label = LABELED_BLOCK_LABEL (*expr_p);
1199 DECL_CONTEXT (label) = current_function_decl;
1200 t = build (LABEL_EXPR, void_type_node, label);
1201 if (body != NULL_TREE)
1202 t = build (COMPOUND_EXPR, void_type_node, body, t);
1208 /* Gimplify a EXIT_BLOCK_EXPR into a GOTO_EXPR. */
1210 static enum gimplify_status
1211 gimplify_exit_block_expr (tree *expr_p)
1213 tree labeled_block = TREE_OPERAND (*expr_p, 0);
1216 /* First operand must be a LABELED_BLOCK_EXPR, which should
1217 already be lowered (or partially lowered) when we get here. */
1218 #if defined ENABLE_CHECKING
1219 if (TREE_CODE (labeled_block) != LABELED_BLOCK_EXPR)
1223 label = LABELED_BLOCK_LABEL (labeled_block);
1224 *expr_p = build1 (GOTO_EXPR, void_type_node, label);
1229 /* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
1233 build_and_jump (tree *label_p)
1235 if (label_p == NULL)
1236 /* If there's nowhere to jump, just fall through. */
1239 if (*label_p == NULL_TREE)
1241 tree label = create_artificial_label ();
1245 return build1 (GOTO_EXPR, void_type_node, *label_p);
1248 /* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
1249 This also involves building a label to jump to and communicating it to
1250 gimplify_loop_expr through gimplify_ctxp->exit_label. */
1252 static enum gimplify_status
1253 gimplify_exit_expr (tree *expr_p)
1255 tree cond = TREE_OPERAND (*expr_p, 0);
1258 expr = build_and_jump (&gimplify_ctxp->exit_label);
1259 expr = build (COND_EXPR, void_type_node, cond, expr, NULL_TREE);
1265 /* A helper function to be called via walk_tree. Mark all labels under *TP
1266 as being forced. To be called for DECL_INITIAL of static variables. */
1269 force_labels_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1273 if (TREE_CODE (*tp) == LABEL_DECL)
1274 FORCED_LABEL (*tp) = 1;
1279 /* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is
1280 different from its canonical type, wrap the whole thing inside a
1281 NOP_EXPR and force the type of the COMPONENT_REF to be the canonical
1284 The canonical type of a COMPONENT_REF is the type of the field being
1285 referenced--unless the field is a bit-field which can be read directly
1286 in a smaller mode, in which case the canonical type is the
1287 sign-appropriate type corresponding to that mode. */
1290 canonicalize_component_ref (tree *expr_p)
1292 tree expr = *expr_p;
1295 if (TREE_CODE (expr) != COMPONENT_REF)
1298 if (INTEGRAL_TYPE_P (TREE_TYPE (expr)))
1299 type = TREE_TYPE (get_unwidened (expr, NULL_TREE));
1301 type = TREE_TYPE (TREE_OPERAND (expr, 1));
1303 if (TREE_TYPE (expr) != type)
1305 tree old_type = TREE_TYPE (expr);
1307 /* Set the type of the COMPONENT_REF to the underlying type. */
1308 TREE_TYPE (expr) = type;
1310 /* And wrap the whole thing inside a NOP_EXPR. */
1311 expr = build1 (NOP_EXPR, old_type, expr);
1317 /* If a NOP conversion is changing a pointer to array of foo to a pointer
1318 to foo, embed that change in the ADDR_EXPR by converting
1323 where L is the lower bound. For simplicity, only do this for constant
1327 canonicalize_addr_expr (tree *expr_p)
1329 tree expr = *expr_p;
1330 tree ctype = TREE_TYPE (expr);
1331 tree addr_expr = TREE_OPERAND (expr, 0);
1332 tree atype = TREE_TYPE (addr_expr);
1333 tree dctype, datype, ddatype, otype, obj_expr;
1335 /* Both cast and addr_expr types should be pointers. */
1336 if (!POINTER_TYPE_P (ctype) || !POINTER_TYPE_P (atype))
1339 /* The addr_expr type should be a pointer to an array. */
1340 datype = TREE_TYPE (atype);
1341 if (TREE_CODE (datype) != ARRAY_TYPE)
1344 /* Both cast and addr_expr types should address the same object type. */
1345 dctype = TREE_TYPE (ctype);
1346 ddatype = TREE_TYPE (datype);
1347 if (!lang_hooks.types_compatible_p (ddatype, dctype))
1350 /* The addr_expr and the object type should match. */
1351 obj_expr = TREE_OPERAND (addr_expr, 0);
1352 otype = TREE_TYPE (obj_expr);
1353 if (!lang_hooks.types_compatible_p (otype, datype))
1356 /* The lower bound and element sizes must be constant. */
1357 if (TREE_CODE (TYPE_SIZE_UNIT (dctype)) != INTEGER_CST
1358 || !TYPE_DOMAIN (datype) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype))
1359 || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype))) != INTEGER_CST)
1362 /* All checks succeeded. Build a new node to merge the cast. */
1363 *expr_p = build4 (ARRAY_REF, dctype, obj_expr,
1364 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1365 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1366 size_binop (EXACT_DIV_EXPR, TYPE_SIZE_UNIT (dctype),
1367 size_int (TYPE_ALIGN (dctype)
1369 *expr_p = build1 (ADDR_EXPR, ctype, *expr_p);
1372 /* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
1373 underneath as appropriate. */
1375 static enum gimplify_status
1376 gimplify_conversion (tree *expr_p)
1378 /* If we still have a conversion at the toplevel, then strip
1379 away all but the outermost conversion. */
1380 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1382 STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0));
1384 /* And remove the outermost conversion if it's useless. */
1385 if (tree_ssa_useless_type_conversion (*expr_p))
1386 *expr_p = TREE_OPERAND (*expr_p, 0);
1389 /* If we still have a conversion at the toplevel,
1390 then canonicalize some constructs. */
1391 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1393 tree sub = TREE_OPERAND (*expr_p, 0);
1395 /* If a NOP conversion is changing the type of a COMPONENT_REF
1396 expression, then canonicalize its type now in order to expose more
1397 redundant conversions. */
1398 if (TREE_CODE (sub) == COMPONENT_REF)
1399 canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0));
1401 /* If a NOP conversion is changing a pointer to array of foo
1402 to a pointer to foo, embed that change in the ADDR_EXPR. */
1403 else if (TREE_CODE (sub) == ADDR_EXPR)
1404 canonicalize_addr_expr (expr_p);
1410 /* Reduce MIN/MAX_EXPR to a COND_EXPR for further gimplification. */
1412 static enum gimplify_status
1413 gimplify_minimax_expr (tree *expr_p, tree *pre_p, tree *post_p)
1415 tree op1 = TREE_OPERAND (*expr_p, 0);
1416 tree op2 = TREE_OPERAND (*expr_p, 1);
1417 enum tree_code code;
1418 enum gimplify_status r0, r1;
1420 if (TREE_CODE (*expr_p) == MIN_EXPR)
1425 r0 = gimplify_expr (&op1, pre_p, post_p, is_gimple_val, fb_rvalue);
1426 r1 = gimplify_expr (&op2, pre_p, post_p, is_gimple_val, fb_rvalue);
1428 *expr_p = build (COND_EXPR, TREE_TYPE (*expr_p),
1429 build (code, boolean_type_node, op1, op2),
1432 if (r0 == GS_ERROR || r1 == GS_ERROR)
1438 /* Subroutine of gimplify_compound_lval.
1439 Converts an ARRAY_REF to the equivalent *(&array + offset) form. */
1441 static enum gimplify_status
1442 gimplify_array_ref_to_plus (tree *expr_p, tree *pre_p, tree *post_p)
1444 tree array = TREE_OPERAND (*expr_p, 0);
1445 tree arrtype = TREE_TYPE (array);
1446 tree elttype = TREE_TYPE (arrtype);
1447 tree size = array_ref_element_size (*expr_p);
1448 tree ptrtype = build_pointer_type (elttype);
1449 enum tree_code add_code = PLUS_EXPR;
1450 tree idx = TREE_OPERAND (*expr_p, 1);
1451 tree minidx = unshare_expr (array_ref_low_bound (*expr_p));
1452 tree offset, addr, result;
1453 enum gimplify_status ret;
1455 /* If the array domain does not start at zero, apply the offset. */
1456 if (!integer_zerop (minidx))
1458 idx = convert (TREE_TYPE (minidx), idx);
1459 idx = fold (build (MINUS_EXPR, TREE_TYPE (minidx), idx, minidx));
1462 /* If the index is negative -- a technically invalid situation now
1463 that we've biased the index back to zero -- then casting it to
1464 unsigned has ill effects. In particular, -1*4U/4U != -1.
1465 Represent this as a subtraction of a positive rather than addition
1466 of a negative. This will prevent any conversion back to ARRAY_REF
1467 from getting the wrong results from the division. */
1468 if (TREE_CODE (idx) == INTEGER_CST && tree_int_cst_sgn (idx) < 0)
1470 idx = fold (build1 (NEGATE_EXPR, TREE_TYPE (idx), idx));
1471 add_code = MINUS_EXPR;
1474 /* Pointer arithmetic must be done in sizetype. */
1475 idx = fold_convert (sizetype, idx);
1477 /* Convert the index to a byte offset. */
1478 offset = size_binop (MULT_EXPR, size, idx);
1480 ret = gimplify_expr (&array, pre_p, post_p, is_gimple_min_lval, fb_lvalue);
1481 if (ret == GS_ERROR)
1484 addr = build_fold_addr_expr_with_type (array, ptrtype);
1485 result = fold (build (add_code, ptrtype, addr, offset));
1486 *expr_p = build1 (INDIRECT_REF, elttype, result);
1491 /* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
1492 node pointed by EXPR_P.
1495 : min_lval '[' val ']'
1497 | compound_lval '[' val ']'
1498 | compound_lval '.' ID
1500 This is not part of the original SIMPLE definition, which separates
1501 array and member references, but it seems reasonable to handle them
1502 together. Also, this way we don't run into problems with union
1503 aliasing; gcc requires that for accesses through a union to alias, the
1504 union reference must be explicit, which was not always the case when we
1505 were splitting up array and member refs.
1507 PRE_P points to the list where side effects that must happen before
1508 *EXPR_P should be stored.
1510 POST_P points to the list where side effects that must happen after
1511 *EXPR_P should be stored. */
1513 static enum gimplify_status
1514 gimplify_compound_lval (tree *expr_p, tree *pre_p,
1515 tree *post_p, fallback_t fallback)
1519 enum gimplify_status ret = GS_OK, tret;
1522 #if defined ENABLE_CHECKING
1523 if (TREE_CODE (*expr_p) != ARRAY_REF
1524 && TREE_CODE (*expr_p) != ARRAY_RANGE_REF
1525 && TREE_CODE (*expr_p) != COMPONENT_REF
1526 && TREE_CODE (*expr_p) != BIT_FIELD_REF
1527 && TREE_CODE (*expr_p) != REALPART_EXPR
1528 && TREE_CODE (*expr_p) != IMAGPART_EXPR)
1532 /* Create a stack of the subexpressions so later we can walk them in
1533 order from inner to outer. */
1534 VARRAY_TREE_INIT (stack, 10, "stack");
1536 /* We can either handle REALPART_EXPR, IMAGEPART_EXPR anything that
1537 handled_components can deal with. */
1539 (handled_component_p (*p)
1540 || TREE_CODE (*p) == REALPART_EXPR || TREE_CODE (*p) == IMAGPART_EXPR);
1541 p = &TREE_OPERAND (*p, 0))
1542 VARRAY_PUSH_TREE (stack, *p);
1544 /* Now STACK is a stack of pointers to all the refs we've walked through
1545 and P points to the innermost expression.
1547 Java requires that we elaborated nodes in source order. That
1548 means we must gimplify the inner expression followed by each of
1549 the indices, in order. But we can't gimplify the inner
1550 expression until we deal with any variable bounds, sizes, or
1551 positions in order to deal with PLACEHOLDER_EXPRs.
1553 So we do this in three steps. First we deal with the annotations
1554 for any variables in the components, then we gimplify the base,
1555 then we gimplify any indices, from left to right. */
1556 for (i = VARRAY_ACTIVE_SIZE (stack) - 1; i >= 0; i--)
1558 tree t = VARRAY_TREE (stack, i);
1560 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1562 /* Gimplify the low bound and element type size and put them into
1563 the ARRAY_REF. If these values are set, they have already been
1565 if (!TREE_OPERAND (t, 2))
1567 tree low = unshare_expr (array_ref_low_bound (t));
1568 if (!is_gimple_min_invariant (low))
1570 TREE_OPERAND (t, 2) = low;
1571 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1572 is_gimple_tmp_var, fb_rvalue);
1573 ret = MIN (ret, tret);
1577 if (!TREE_OPERAND (t, 3))
1579 tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
1580 tree elmt_size = unshare_expr (array_ref_element_size (t));
1581 tree factor = size_int (TYPE_ALIGN (elmt_type) / BITS_PER_UNIT);
1583 /* Divide the element size by the alignment of the element
1585 elmt_size = size_binop (EXACT_DIV_EXPR, elmt_size, factor);
1587 if (!is_gimple_min_invariant (elmt_size))
1589 TREE_OPERAND (t, 3) = elmt_size;
1590 tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p,
1591 is_gimple_tmp_var, fb_rvalue);
1592 ret = MIN (ret, tret);
1596 else if (TREE_CODE (t) == COMPONENT_REF)
1598 /* Set the field offset into T and gimplify it. */
1599 if (!TREE_OPERAND (t, 2))
1601 tree offset = unshare_expr (component_ref_field_offset (t));
1602 tree field = TREE_OPERAND (t, 1);
1604 = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
1606 /* Divide the offset by its alignment. */
1607 offset = size_binop (EXACT_DIV_EXPR, offset, factor);
1609 if (!is_gimple_min_invariant (offset))
1611 TREE_OPERAND (t, 2) = offset;
1612 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1613 is_gimple_tmp_var, fb_rvalue);
1614 ret = MIN (ret, tret);
1620 /* Step 2 is to gimplify the base expression. */
1621 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1622 ret = MIN (ret, tret);
1624 /* And finally, the indices and operands to BIT_FIELD_REF. During this
1625 loop we also remove any useless conversions. */
1626 for (; VARRAY_ACTIVE_SIZE (stack) > 0; )
1628 tree t = VARRAY_TOP_TREE (stack);
1630 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1632 /* Gimplify the dimension.
1633 Temporary fix for gcc.c-torture/execute/20040313-1.c.
1634 Gimplify non-constant array indices into a temporary
1636 FIXME - The real fix is to gimplify post-modify
1637 expressions into a minimal gimple lvalue. However, that
1638 exposes bugs in alias analysis. The alias analyzer does
1639 not handle &PTR->FIELD very well. Will fix after the
1640 branch is merged into mainline (dnovillo 2004-05-03). */
1641 if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
1643 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1644 is_gimple_tmp_var, fb_rvalue);
1645 ret = MIN (ret, tret);
1648 else if (TREE_CODE (t) == BIT_FIELD_REF)
1650 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1651 is_gimple_val, fb_rvalue);
1652 ret = MIN (ret, tret);
1653 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1654 is_gimple_val, fb_rvalue);
1655 ret = MIN (ret, tret);
1658 STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0));
1660 /* The innermost expression P may have originally had TREE_SIDE_EFFECTS
1661 set which would have caused all the outer expressions in EXPR_P
1662 leading to P to also have had TREE_SIDE_EFFECTS set. */
1663 recalculate_side_effects (t);
1667 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1668 ret = MIN (ret, tret);
1670 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
1671 if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF)
1673 canonicalize_component_ref (expr_p);
1674 ret = MIN (ret, GS_OK);
1680 /* Gimplify the self modifying expression pointed by EXPR_P (++, --, +=, -=).
1682 PRE_P points to the list where side effects that must happen before
1683 *EXPR_P should be stored.
1685 POST_P points to the list where side effects that must happen after
1686 *EXPR_P should be stored.
1688 WANT_VALUE is nonzero iff we want to use the value of this expression
1689 in another expression. */
1691 static enum gimplify_status
1692 gimplify_self_mod_expr (tree *expr_p, tree *pre_p, tree *post_p,
1695 enum tree_code code;
1696 tree lhs, lvalue, rhs, t1;
1698 enum tree_code arith_code;
1699 enum gimplify_status ret;
1701 code = TREE_CODE (*expr_p);
1703 #if defined ENABLE_CHECKING
1704 if (code != POSTINCREMENT_EXPR
1705 && code != POSTDECREMENT_EXPR
1706 && code != PREINCREMENT_EXPR
1707 && code != PREDECREMENT_EXPR)
1711 /* Prefix or postfix? */
1712 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
1713 /* Faster to treat as prefix if result is not used. */
1714 postfix = want_value;
1718 /* Add or subtract? */
1719 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
1720 arith_code = PLUS_EXPR;
1722 arith_code = MINUS_EXPR;
1724 /* Gimplify the LHS into a GIMPLE lvalue. */
1725 lvalue = TREE_OPERAND (*expr_p, 0);
1726 ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
1727 if (ret == GS_ERROR)
1730 /* Extract the operands to the arithmetic operation. */
1732 rhs = TREE_OPERAND (*expr_p, 1);
1734 /* For postfix operator, we evaluate the LHS to an rvalue and then use
1735 that as the result value and in the postqueue operation. */
1738 ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
1739 if (ret == GS_ERROR)
1743 t1 = build (arith_code, TREE_TYPE (*expr_p), lhs, rhs);
1744 t1 = build (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
1748 gimplify_and_add (t1, post_p);
1759 /* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
1762 maybe_with_size_expr (tree *expr_p)
1764 tree expr, type, size;
1767 type = TREE_TYPE (expr);
1768 if (type == error_mark_node)
1771 size = TYPE_SIZE_UNIT (type);
1772 if (size && TREE_CODE (size) != INTEGER_CST)
1774 size = unshare_expr (size);
1775 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr);
1776 *expr_p = build2 (WITH_SIZE_EXPR, type, expr, size);
1780 /* Subroutine of gimplify_call_expr: Gimplify a single argument. */
1782 static enum gimplify_status
1783 gimplify_arg (tree *expr_p, tree *pre_p)
1785 bool (*test) (tree);
1788 /* In general, we allow lvalues for function arguments to avoid
1789 extra overhead of copying large aggregates out of even larger
1790 aggregates into temporaries only to copy the temporaries to
1791 the argument list. Make optimizers happy by pulling out to
1792 temporaries those types that fit in registers. */
1793 if (is_gimple_reg_type (TREE_TYPE (*expr_p)))
1794 test = is_gimple_val, fb = fb_rvalue;
1796 test = is_gimple_lvalue, fb = fb_either;
1798 /* If this is a variable sized type, we must remember the size. */
1799 maybe_with_size_expr (expr_p);
1801 /* There is a sequence point before a function call. Side effects in
1802 the argument list must occur before the actual call. So, when
1803 gimplifying arguments, force gimplify_expr to use an internal
1804 post queue which is then appended to the end of PRE_P. */
1805 return gimplify_expr (expr_p, pre_p, NULL, test, fb);
1808 /* Gimplify the CALL_EXPR node pointed by EXPR_P. PRE_P points to the
1809 list where side effects that must happen before *EXPR_P should be stored.
1810 WANT_VALUE is true if the result of the call is desired. */
1812 static enum gimplify_status
1813 gimplify_call_expr (tree *expr_p, tree *pre_p, bool want_value)
1817 enum gimplify_status ret;
1819 #if defined ENABLE_CHECKING
1820 if (TREE_CODE (*expr_p) != CALL_EXPR)
1824 /* For reliable diagnostics during inlining, it is necessary that
1825 every call_expr be annotated with file and line. */
1826 if (! EXPR_HAS_LOCATION (*expr_p))
1827 SET_EXPR_LOCATION (*expr_p, input_location);
1829 /* This may be a call to a builtin function.
1831 Builtin function calls may be transformed into different
1832 (and more efficient) builtin function calls under certain
1833 circumstances. Unfortunately, gimplification can muck things
1834 up enough that the builtin expanders are not aware that certain
1835 transformations are still valid.
1837 So we attempt transformation/gimplification of the call before
1838 we gimplify the CALL_EXPR. At this time we do not manage to
1839 transform all calls in the same manner as the expanders do, but
1840 we do transform most of them. */
1841 decl = get_callee_fndecl (*expr_p);
1842 if (decl && DECL_BUILT_IN (decl))
1846 /* If it is allocation of stack, record the need to restore the memory
1847 when the enclosing bind_expr is exited. */
1848 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_STACK_ALLOC)
1849 gimplify_ctxp->save_stack = true;
1851 /* If it is restore of the stack, reset it, since it means we are
1852 regimplifying the bind_expr. Note that we use the fact that
1853 for try_finally_expr, try part is processed first. */
1854 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_STACK_RESTORE)
1855 gimplify_ctxp->save_stack = false;
1857 new = simplify_builtin (*expr_p, !want_value);
1859 if (new && new != *expr_p)
1861 /* There was a transformation of this call which computes the
1862 same value, but in a more efficient way. Return and try
1868 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_VA_START)
1869 /* Avoid gimplifying the second argument to va_start, which needs
1870 to be the plain PARM_DECL. */
1871 return gimplify_arg (&TREE_VALUE (TREE_OPERAND (*expr_p, 1)), pre_p);
1874 /* There is a sequence point before the call, so any side effects in
1875 the calling expression must occur before the actual call. Force
1876 gimplify_expr to use an internal post queue. */
1877 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, NULL,
1878 is_gimple_call_addr, fb_rvalue);
1880 if (PUSH_ARGS_REVERSED)
1881 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1882 for (arglist = TREE_OPERAND (*expr_p, 1); arglist;
1883 arglist = TREE_CHAIN (arglist))
1885 enum gimplify_status t;
1887 t = gimplify_arg (&TREE_VALUE (arglist), pre_p);
1892 if (PUSH_ARGS_REVERSED)
1893 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1895 /* Try this again in case gimplification exposed something. */
1896 if (ret != GS_ERROR && decl && DECL_BUILT_IN (decl))
1898 tree new = simplify_builtin (*expr_p, !want_value);
1900 if (new && new != *expr_p)
1902 /* There was a transformation of this call which computes the
1903 same value, but in a more efficient way. Return and try
1910 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
1911 decl. This allows us to eliminate redundant or useless
1912 calls to "const" functions. */
1913 if (TREE_CODE (*expr_p) == CALL_EXPR
1914 && (call_expr_flags (*expr_p) & (ECF_CONST | ECF_PURE)))
1915 TREE_SIDE_EFFECTS (*expr_p) = 0;
1920 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
1921 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
1923 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
1924 condition is true or false, respectively. If null, we should generate
1925 our own to skip over the evaluation of this specific expression.
1927 This function is the tree equivalent of do_jump.
1929 shortcut_cond_r should only be called by shortcut_cond_expr. */
1932 shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p)
1934 tree local_label = NULL_TREE;
1935 tree t, expr = NULL;
1937 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
1938 retain the shortcut semantics. Just insert the gotos here;
1939 shortcut_cond_expr will append the real blocks later. */
1940 if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
1942 /* Turn if (a && b) into
1944 if (a); else goto no;
1945 if (b) goto yes; else goto no;
1948 if (false_label_p == NULL)
1949 false_label_p = &local_label;
1951 t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p);
1952 append_to_statement_list (t, &expr);
1954 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1956 append_to_statement_list (t, &expr);
1958 else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
1960 /* Turn if (a || b) into
1963 if (b) goto yes; else goto no;
1966 if (true_label_p == NULL)
1967 true_label_p = &local_label;
1969 t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL);
1970 append_to_statement_list (t, &expr);
1972 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1974 append_to_statement_list (t, &expr);
1976 else if (TREE_CODE (pred) == COND_EXPR)
1978 /* As long as we're messing with gotos, turn if (a ? b : c) into
1980 if (b) goto yes; else goto no;
1982 if (c) goto yes; else goto no; */
1983 expr = build (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
1984 shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1986 shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
1991 expr = build (COND_EXPR, void_type_node, pred,
1992 build_and_jump (true_label_p),
1993 build_and_jump (false_label_p));
1998 t = build1 (LABEL_EXPR, void_type_node, local_label);
1999 append_to_statement_list (t, &expr);
2006 shortcut_cond_expr (tree expr)
2008 tree pred = TREE_OPERAND (expr, 0);
2009 tree then_ = TREE_OPERAND (expr, 1);
2010 tree else_ = TREE_OPERAND (expr, 2);
2011 tree true_label, false_label, end_label, t;
2013 tree *false_label_p;
2014 bool emit_end, emit_false;
2015 bool then_se = then_ && TREE_SIDE_EFFECTS (then_);
2016 bool else_se = else_ && TREE_SIDE_EFFECTS (else_);
2018 /* First do simple transformations. */
2021 /* If there is no 'else', turn (a && b) into if (a) if (b). */
2022 while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2024 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2025 then_ = shortcut_cond_expr (expr);
2026 pred = TREE_OPERAND (pred, 0);
2027 expr = build (COND_EXPR, void_type_node, pred, then_, NULL_TREE);
2032 /* If there is no 'then', turn
2035 if (a); else if (b); else d. */
2036 while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2038 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2039 else_ = shortcut_cond_expr (expr);
2040 pred = TREE_OPERAND (pred, 0);
2041 expr = build (COND_EXPR, void_type_node, pred, NULL_TREE, else_);
2045 /* If we're done, great. */
2046 if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
2047 && TREE_CODE (pred) != TRUTH_ORIF_EXPR)
2050 /* Otherwise we need to mess with gotos. Change
2053 if (a); else goto no;
2056 and recursively gimplify the condition. */
2058 true_label = false_label = end_label = NULL_TREE;
2060 /* If our arms just jump somewhere, hijack those labels so we don't
2061 generate jumps to jumps. */
2064 && TREE_CODE (then_) == GOTO_EXPR
2065 && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
2067 true_label = GOTO_DESTINATION (then_);
2073 && TREE_CODE (else_) == GOTO_EXPR
2074 && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
2076 false_label = GOTO_DESTINATION (else_);
2081 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2083 true_label_p = &true_label;
2085 true_label_p = NULL;
2087 /* The 'else' branch also needs a label if it contains interesting code. */
2088 if (false_label || else_se)
2089 false_label_p = &false_label;
2091 false_label_p = NULL;
2093 /* If there was nothing else in our arms, just forward the label(s). */
2094 if (!then_se && !else_se)
2095 return shortcut_cond_r (pred, true_label_p, false_label_p);
2097 /* If our last subexpression already has a terminal label, reuse it. */
2099 expr = expr_last (else_);
2101 expr = expr_last (then_);
2104 if (expr && TREE_CODE (expr) == LABEL_EXPR)
2105 end_label = LABEL_EXPR_LABEL (expr);
2107 /* If we don't care about jumping to the 'else' branch, jump to the end
2108 if the condition is false. */
2110 false_label_p = &end_label;
2112 /* We only want to emit these labels if we aren't hijacking them. */
2113 emit_end = (end_label == NULL_TREE);
2114 emit_false = (false_label == NULL_TREE);
2116 pred = shortcut_cond_r (pred, true_label_p, false_label_p);
2119 append_to_statement_list (pred, &expr);
2121 append_to_statement_list (then_, &expr);
2124 t = build_and_jump (&end_label);
2125 append_to_statement_list (t, &expr);
2128 t = build1 (LABEL_EXPR, void_type_node, false_label);
2129 append_to_statement_list (t, &expr);
2131 append_to_statement_list (else_, &expr);
2133 if (emit_end && end_label)
2135 t = build1 (LABEL_EXPR, void_type_node, end_label);
2136 append_to_statement_list (t, &expr);
2142 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2145 gimple_boolify (tree expr)
2147 tree type = TREE_TYPE (expr);
2149 if (TREE_CODE (type) == BOOLEAN_TYPE)
2152 /* If this is the predicate of a COND_EXPR, it might not even be a
2154 expr = lang_hooks.truthvalue_conversion (expr);
2156 switch (TREE_CODE (expr))
2158 case TRUTH_AND_EXPR:
2160 case TRUTH_XOR_EXPR:
2161 case TRUTH_ANDIF_EXPR:
2162 case TRUTH_ORIF_EXPR:
2163 /* Also boolify the arguments of truth exprs. */
2164 TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
2167 case TRUTH_NOT_EXPR:
2168 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2171 case EQ_EXPR: case NE_EXPR:
2172 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2173 /* These expressions always produce boolean results. */
2174 TREE_TYPE (expr) = boolean_type_node;
2178 /* Other expressions that get here must have boolean values, but
2179 might need to be converted to the appropriate mode. */
2180 return convert (boolean_type_node, expr);
2184 /* Convert the conditional expression pointed by EXPR_P '(p) ? a : b;'
2193 The second form is used when *EXPR_P is of type void.
2195 TARGET is the tree for T1 above.
2197 PRE_P points to the list where side effects that must happen before
2198 *EXPR_P should be stored. */
2200 static enum gimplify_status
2201 gimplify_cond_expr (tree *expr_p, tree *pre_p, tree target)
2203 tree expr = *expr_p;
2205 enum gimplify_status ret;
2207 type = TREE_TYPE (expr);
2209 TREE_TYPE (expr) = void_type_node;
2211 /* If this COND_EXPR has a value, copy the values into a temporary within
2213 else if (! VOID_TYPE_P (type))
2222 tmp = create_tmp_var (TREE_TYPE (expr), "iftmp");
2226 /* Build the then clause, 't1 = a;'. But don't build an assignment
2227 if this branch is void; in C++ it can be, if it's a throw. */
2228 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2229 TREE_OPERAND (expr, 1)
2230 = build (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 1));
2232 /* Build the else clause, 't1 = b;'. */
2233 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2234 TREE_OPERAND (expr, 2)
2235 = build (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 2));
2237 TREE_TYPE (expr) = void_type_node;
2238 recalculate_side_effects (expr);
2240 /* Move the COND_EXPR to the prequeue and use the temp in its place. */
2241 gimplify_and_add (expr, pre_p);
2247 /* Make sure the condition has BOOLEAN_TYPE. */
2248 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2250 /* Break apart && and || conditions. */
2251 if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
2252 || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
2254 expr = shortcut_cond_expr (expr);
2256 if (expr != *expr_p)
2260 /* We can't rely on gimplify_expr to re-gimplify the expanded
2261 form properly, as cleanups might cause the target labels to be
2262 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2263 set up a conditional context. */
2264 gimple_push_condition ();
2265 gimplify_stmt (expr_p);
2266 gimple_pop_condition (pre_p);
2272 /* Now do the normal gimplification. */
2273 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2274 is_gimple_condexpr, fb_rvalue);
2276 gimple_push_condition ();
2278 gimplify_to_stmt_list (&TREE_OPERAND (expr, 1));
2279 gimplify_to_stmt_list (&TREE_OPERAND (expr, 2));
2280 recalculate_side_effects (expr);
2282 gimple_pop_condition (pre_p);
2284 if (ret == GS_ERROR)
2286 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2288 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 2)))
2289 /* Rewrite "if (a); else b" to "if (!a) b" */
2291 TREE_OPERAND (expr, 0) = invert_truthvalue (TREE_OPERAND (expr, 0));
2292 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2293 is_gimple_condexpr, fb_rvalue);
2295 tmp = TREE_OPERAND (expr, 1);
2296 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 2);
2297 TREE_OPERAND (expr, 2) = tmp;
2300 /* Both arms are empty; replace the COND_EXPR with its predicate. */
2301 expr = TREE_OPERAND (expr, 0);
2307 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2308 a call to __builtin_memcpy. */
2310 static enum gimplify_status
2311 gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value)
2313 tree args, t, to, to_ptr, from;
2315 to = TREE_OPERAND (*expr_p, 0);
2316 from = TREE_OPERAND (*expr_p, 1);
2318 args = tree_cons (NULL, size, NULL);
2320 t = build_fold_addr_expr (from);
2321 args = tree_cons (NULL, t, args);
2323 to_ptr = build_fold_addr_expr (to);
2324 args = tree_cons (NULL, to_ptr, args);
2325 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
2326 t = build_function_call_expr (t, args);
2330 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2331 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2338 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2339 a call to __builtin_memset. In this case we know that the RHS is
2340 a CONSTRUCTOR with an empty element list. */
2342 static enum gimplify_status
2343 gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value)
2345 tree args, t, to, to_ptr;
2347 to = TREE_OPERAND (*expr_p, 0);
2349 args = tree_cons (NULL, size, NULL);
2351 args = tree_cons (NULL, integer_zero_node, args);
2353 to_ptr = build_fold_addr_expr (to);
2354 args = tree_cons (NULL, to_ptr, args);
2355 t = implicit_built_in_decls[BUILT_IN_MEMSET];
2356 t = build_function_call_expr (t, args);
2360 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2361 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2368 /* A subroutine of gimplify_modify_expr. Break out elements of a
2369 CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.
2371 Note that we still need to clear any elements that don't have explicit
2372 initializers, so if not all elements are initialized we keep the
2373 original MODIFY_EXPR, we just remove all of the constructor elements. */
2375 static enum gimplify_status
2376 gimplify_init_constructor (tree *expr_p, tree *pre_p,
2377 tree *post_p, bool want_value)
2379 tree object = TREE_OPERAND (*expr_p, 0);
2380 tree ctor = TREE_OPERAND (*expr_p, 1);
2381 tree type = TREE_TYPE (ctor);
2382 enum gimplify_status ret;
2385 if (TREE_CODE (ctor) != CONSTRUCTOR)
2386 return GS_UNHANDLED;
2388 elt_list = CONSTRUCTOR_ELTS (ctor);
2391 switch (TREE_CODE (type))
2395 case QUAL_UNION_TYPE:
2398 HOST_WIDE_INT i, num_elements, num_nonzero_elements;
2399 HOST_WIDE_INT num_nonconstant_elements;
2402 /* Aggregate types must lower constructors to initialization of
2403 individual elements. The exception is that a CONSTRUCTOR node
2404 with no elements indicates zero-initialization of the whole. */
2405 if (elt_list == NULL)
2413 return GS_UNHANDLED;
2416 categorize_ctor_elements (ctor, &num_nonzero_elements,
2417 &num_nonconstant_elements);
2418 num_elements = count_type_elements (TREE_TYPE (ctor));
2420 /* If a const aggregate variable is being initialized, then it
2421 should never be a lose to promote the variable to be static. */
2422 if (num_nonconstant_elements == 0
2423 && TREE_READONLY (object)
2424 && TREE_CODE (object) == VAR_DECL)
2426 DECL_INITIAL (object) = ctor;
2427 TREE_STATIC (object) = 1;
2428 if (!DECL_NAME (object))
2429 DECL_NAME (object) = create_tmp_var_name ("C");
2430 walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL);
2432 /* ??? C++ doesn't automatically append a .<number> to the
2433 assembler name, and even when it does, it looks a FE private
2434 data structures to figure out what that number should be,
2435 which are not set for this variable. I suppose this is
2436 important for local statics for inline functions, which aren't
2437 "local" in the object file sense. So in order to get a unique
2438 TU-local symbol, we must invoke the lhd version now. */
2439 lhd_set_decl_assembler_name (object);
2441 *expr_p = NULL_TREE;
2445 /* If there are "lots" of initialized elements, and all of them
2446 are valid address constants, then the entire initializer can
2447 be dropped to memory, and then memcpy'd out. */
2448 if (num_nonconstant_elements == 0)
2450 HOST_WIDE_INT size = int_size_in_bytes (type);
2453 /* ??? We can still get unbounded array types, at least
2454 from the C++ front end. This seems wrong, but attempt
2455 to work around it for now. */
2458 size = int_size_in_bytes (TREE_TYPE (object));
2460 TREE_TYPE (ctor) = type = TREE_TYPE (object);
2463 /* Find the maximum alignment we can assume for the object. */
2464 /* ??? Make use of DECL_OFFSET_ALIGN. */
2465 if (DECL_P (object))
2466 align = DECL_ALIGN (object);
2468 align = TYPE_ALIGN (type);
2470 if (size > 0 && !can_move_by_pieces (size, align))
2472 tree new = create_tmp_var_raw (type, "C");
2473 gimple_add_tmp_var (new);
2474 TREE_STATIC (new) = 1;
2475 TREE_READONLY (new) = 1;
2476 DECL_INITIAL (new) = ctor;
2477 if (align > DECL_ALIGN (new))
2479 DECL_ALIGN (new) = align;
2480 DECL_USER_ALIGN (new) = 1;
2482 walk_tree (&DECL_INITIAL (new), force_labels_r, NULL, NULL);
2484 TREE_OPERAND (*expr_p, 1) = new;
2489 /* If there are "lots" of initialized elements, even discounting
2490 those that are not address constants (and thus *must* be
2491 computed at runtime), then partition the constructor into
2492 constant and non-constant parts. Block copy the constant
2493 parts in, then generate code for the non-constant parts. */
2494 /* TODO. There's code in cp/typeck.c to do this. */
2496 /* If there are "lots" of zeros, then block clear the object first. */
2498 if (num_elements - num_nonzero_elements > CLEAR_RATIO
2499 && num_nonzero_elements < num_elements/4)
2502 /* ??? This bit ought not be needed. For any element not present
2503 in the initializer, we should simply set them to zero. Except
2504 we'd need to *find* the elements that are not present, and that
2505 requires trickery to avoid quadratic compile-time behavior in
2506 large cases or excessive memory use in small cases. */
2509 HOST_WIDE_INT len = list_length (elt_list);
2510 if (TREE_CODE (type) == ARRAY_TYPE)
2512 tree nelts = array_type_nelts (type);
2513 if (!host_integerp (nelts, 1)
2514 || tree_low_cst (nelts, 1) + 1 != len)
2517 else if (len != fields_length (type))
2523 /* Zap the CONSTRUCTOR element list, which simplifies this case.
2524 Note that we still have to gimplify, in order to handle the
2525 case of variable sized types. Make an unshared copy of
2526 OBJECT before that so we can match a PLACEHOLDER_EXPR to it
2527 later, if needed. */
2528 CONSTRUCTOR_ELTS (ctor) = NULL_TREE;
2529 object = unshare_expr (TREE_OPERAND (*expr_p, 0));
2530 gimplify_stmt (expr_p);
2531 append_to_statement_list (*expr_p, pre_p);
2534 for (i = 0; elt_list; i++, elt_list = TREE_CHAIN (elt_list))
2536 tree purpose, value, cref, init;
2538 purpose = TREE_PURPOSE (elt_list);
2539 value = TREE_VALUE (elt_list);
2541 if (cleared && initializer_zerop (value))
2544 if (TREE_CODE (type) == ARRAY_TYPE)
2546 tree t = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object)));
2548 /* ??? Here's to hoping the front end fills in all of the
2549 indicies, so we don't have to figure out what's missing
2553 /* ??? Need to handle this. */
2554 if (TREE_CODE (purpose) == RANGE_EXPR)
2557 cref = build (ARRAY_REF, t, unshare_expr (object), purpose,
2558 NULL_TREE, NULL_TREE);
2561 cref = build (COMPONENT_REF, TREE_TYPE (purpose),
2562 unshare_expr (object), purpose, NULL_TREE);
2564 init = build (MODIFY_EXPR, TREE_TYPE (purpose), cref, value);
2566 /* Each member initialization is a full-expression. */
2567 gimplify_and_add (init, pre_p);
2570 *expr_p = NULL_TREE;
2578 /* Extract the real and imaginary parts out of the ctor. */
2582 r = TREE_VALUE (elt_list);
2583 elt_list = TREE_CHAIN (elt_list);
2586 i = TREE_VALUE (elt_list);
2587 if (TREE_CHAIN (elt_list))
2591 if (r == NULL || i == NULL)
2593 tree zero = convert (TREE_TYPE (type), integer_zero_node);
2600 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
2601 represent creation of a complex value. */
2602 if (TREE_CONSTANT (r) && TREE_CONSTANT (i))
2604 ctor = build_complex (type, r, i);
2605 TREE_OPERAND (*expr_p, 1) = ctor;
2609 ctor = build (COMPLEX_EXPR, type, r, i);
2610 TREE_OPERAND (*expr_p, 1) = ctor;
2611 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
2612 is_gimple_tmp_rhs, fb_rvalue);
2618 /* Go ahead and simplify constant constructors to VECTOR_CST. */
2619 if (TREE_CONSTANT (ctor))
2620 TREE_OPERAND (*expr_p, 1) = build_vector (type, elt_list);
2623 /* Vector types use CONSTRUCTOR all the way through gimple
2624 compilation as a general initializer. */
2625 for (; elt_list; elt_list = TREE_CHAIN (elt_list))
2627 enum gimplify_status tret;
2628 tret = gimplify_expr (&TREE_VALUE (elt_list), pre_p, post_p,
2629 is_gimple_constructor_elt, fb_rvalue);
2630 if (tret == GS_ERROR)
2637 /* So how did we get a CONSTRUCTOR for a scalar type? */
2641 if (ret == GS_ERROR)
2643 else if (want_value)
2645 append_to_statement_list (*expr_p, pre_p);
2653 /* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs
2654 based on the code of the RHS. We loop for as long as something changes. */
2656 static enum gimplify_status
2657 gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p,
2658 tree *post_p, bool want_value)
2660 enum gimplify_status ret = GS_OK;
2662 while (ret != GS_UNHANDLED)
2663 switch (TREE_CODE (*from_p))
2667 /* If we are initializing something from a TARGET_EXPR, strip the
2668 TARGET_EXPR and initialize it directly, if possible. This can't
2669 be done if the initializer is void, since that implies that the
2670 temporary is set in some non-trivial way.
2672 ??? What about code that pulls out the temp and uses it
2673 elsewhere? I think that such code never uses the TARGET_EXPR as
2674 an initializer. If I'm wrong, we'll abort because the temp won't
2675 have any RTL. In that case, I guess we'll need to replace
2676 references somehow. */
2677 tree init = TARGET_EXPR_INITIAL (*from_p);
2679 if (!VOID_TYPE_P (TREE_TYPE (init)))
2690 /* Remove any COMPOUND_EXPR in the RHS so the following cases will be
2692 gimplify_compound_expr (from_p, pre_p, true);
2697 /* If we're initializing from a CONSTRUCTOR, break this into
2698 individual MODIFY_EXPRs. */
2699 return gimplify_init_constructor (expr_p, pre_p, post_p, want_value);
2702 /* If we're assigning from a ?: expression with ADDRESSABLE type, push
2703 the assignment down into the branches, since we can't generate a
2704 temporary of such a type. */
2705 if (TREE_ADDRESSABLE (TREE_TYPE (*from_p)))
2708 return gimplify_cond_expr (expr_p, pre_p, *to_p);
2722 /* Gimplify the MODIFY_EXPR node pointed by EXPR_P.
2728 PRE_P points to the list where side effects that must happen before
2729 *EXPR_P should be stored.
2731 POST_P points to the list where side effects that must happen after
2732 *EXPR_P should be stored.
2734 WANT_VALUE is nonzero iff we want to use the value of this expression
2735 in another expression. */
2737 static enum gimplify_status
2738 gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value)
2740 tree *from_p = &TREE_OPERAND (*expr_p, 1);
2741 tree *to_p = &TREE_OPERAND (*expr_p, 0);
2742 enum gimplify_status ret = GS_UNHANDLED;
2744 #if defined ENABLE_CHECKING
2745 if (TREE_CODE (*expr_p) != MODIFY_EXPR && TREE_CODE (*expr_p) != INIT_EXPR)
2749 /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer useful. */
2750 if (TREE_CODE (*expr_p) == INIT_EXPR)
2751 TREE_SET_CODE (*expr_p, MODIFY_EXPR);
2753 /* See if any simplifications can be done based on what the RHS is. */
2754 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2756 if (ret != GS_UNHANDLED)
2759 /* If the value being copied is of variable width, compute the length
2760 of the copy into a WITH_SIZE_EXPR. Note that we need to do this
2761 before gimplifying any of the operands so that we can resolve any
2762 PLACEHOLDER_EXPRs in the size. Also note that the RTL expander uses
2763 the size of the expression to be copied, not of the destination, so
2764 that is what we must here. */
2765 maybe_with_size_expr (from_p);
2767 ret = gimplify_expr (to_p, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
2768 if (ret == GS_ERROR)
2771 ret = gimplify_expr (from_p, pre_p, post_p,
2772 rhs_predicate_for (*to_p), fb_rvalue);
2773 if (ret == GS_ERROR)
2776 /* Now see if the above changed *from_p to something we handle specially. */
2777 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
2779 if (ret != GS_UNHANDLED)
2782 /* If we've got a variable sized assignment between two lvalues (i.e. does
2783 not involve a call), then we can make things a bit more straightforward
2784 by converting the assignment to memcpy or memset. */
2785 if (TREE_CODE (*from_p) == WITH_SIZE_EXPR)
2787 tree from = TREE_OPERAND (*from_p, 0);
2788 tree size = TREE_OPERAND (*from_p, 1);
2790 if (TREE_CODE (from) == CONSTRUCTOR)
2791 return gimplify_modify_expr_to_memset (expr_p, size, want_value);
2792 if (is_gimple_addr_expr_arg (from))
2795 return gimplify_modify_expr_to_memcpy (expr_p, size, want_value);
2799 /* If the destination is already simple, nothing else needed. */
2800 if (is_gimple_tmp_var (*to_p) || !want_value)
2807 append_to_statement_list (*expr_p, pre_p);
2814 /* Gimplify a comparison between two variable-sized objects. Do this
2815 with a call to BUILT_IN_MEMCMP. */
2817 static enum gimplify_status
2818 gimplify_variable_sized_compare (tree *expr_p)
2820 tree op0 = TREE_OPERAND (*expr_p, 0);
2821 tree op1 = TREE_OPERAND (*expr_p, 1);
2824 t = TYPE_SIZE_UNIT (TREE_TYPE (op0));
2825 t = unshare_expr (t);
2826 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, op0);
2827 args = tree_cons (NULL, t, NULL);
2828 t = build_fold_addr_expr (op1);
2829 args = tree_cons (NULL, t, args);
2830 dest = build_fold_addr_expr (op0);
2831 args = tree_cons (NULL, dest, args);
2832 t = implicit_built_in_decls[BUILT_IN_MEMCMP];
2833 t = build_function_call_expr (t, args);
2835 = build (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), t, integer_zero_node);
2840 /* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P
2841 points to the expression to gimplify.
2843 Expressions of the form 'a && b' are gimplified to:
2845 a && b ? true : false
2847 gimplify_cond_expr will do the rest.
2849 PRE_P points to the list where side effects that must happen before
2850 *EXPR_P should be stored. */
2852 static enum gimplify_status
2853 gimplify_boolean_expr (tree *expr_p)
2855 /* Preserve the original type of the expression. */
2856 tree type = TREE_TYPE (*expr_p);
2858 *expr_p = build (COND_EXPR, type, *expr_p,
2859 convert (type, boolean_true_node),
2860 convert (type, boolean_false_node));
2865 /* Gimplifies an expression sequence. This function gimplifies each
2866 expression and re-writes the original expression with the last
2867 expression of the sequence in GIMPLE form.
2869 PRE_P points to the list where the side effects for all the
2870 expressions in the sequence will be emitted.
2872 WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */
2873 /* ??? Should rearrange to share the pre-queue with all the indirect
2874 invocations of gimplify_expr. Would probably save on creations
2875 of statement_list nodes. */
2877 static enum gimplify_status
2878 gimplify_compound_expr (tree *expr_p, tree *pre_p, bool want_value)
2884 tree *sub_p = &TREE_OPERAND (t, 0);
2886 if (TREE_CODE (*sub_p) == COMPOUND_EXPR)
2887 gimplify_compound_expr (sub_p, pre_p, false);
2889 gimplify_stmt (sub_p);
2890 append_to_statement_list (*sub_p, pre_p);
2892 t = TREE_OPERAND (t, 1);
2894 while (TREE_CODE (t) == COMPOUND_EXPR);
2901 gimplify_stmt (expr_p);
2906 /* Gimplifies a statement list. These may be created either by an
2907 enlightened front-end, or by shortcut_cond_expr. */
2909 static enum gimplify_status
2910 gimplify_statement_list (tree *expr_p)
2912 tree_stmt_iterator i = tsi_start (*expr_p);
2914 while (!tsi_end_p (i))
2918 gimplify_stmt (tsi_stmt_ptr (i));
2923 else if (TREE_CODE (t) == STATEMENT_LIST)
2925 tsi_link_before (&i, t, TSI_SAME_STMT);
2935 /* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to
2936 gimplify. After gimplification, EXPR_P will point to a new temporary
2937 that holds the original value of the SAVE_EXPR node.
2939 PRE_P points to the list where side effects that must happen before
2940 *EXPR_P should be stored. */
2942 static enum gimplify_status
2943 gimplify_save_expr (tree *expr_p, tree *pre_p, tree *post_p)
2945 enum gimplify_status ret = GS_ALL_DONE;
2948 #if defined ENABLE_CHECKING
2949 if (TREE_CODE (*expr_p) != SAVE_EXPR)
2953 val = TREE_OPERAND (*expr_p, 0);
2955 /* If the operand is already a GIMPLE temporary, just re-write the
2957 if (is_gimple_tmp_var (val))
2959 /* The operand may be a void-valued expression such as SAVE_EXPRs
2960 generated by the Java frontend for class initialization. It is
2961 being executed only for its side-effects. */
2962 else if (TREE_TYPE (val) == void_type_node)
2964 tree body = TREE_OPERAND (*expr_p, 0);
2965 ret = gimplify_expr (& body, pre_p, post_p, is_gimple_stmt, fb_none);
2966 append_to_statement_list (body, pre_p);
2970 *expr_p = TREE_OPERAND (*expr_p, 0)
2971 = get_initialized_tmp_var (val, pre_p, post_p);
2976 /* Re-write the ADDR_EXPR node pointed by EXPR_P
2983 PRE_P points to the list where side effects that must happen before
2984 *EXPR_P should be stored.
2986 POST_P points to the list where side effects that must happen after
2987 *EXPR_P should be stored. */
2989 static enum gimplify_status
2990 gimplify_addr_expr (tree *expr_p, tree *pre_p, tree *post_p)
2992 tree expr = *expr_p;
2993 tree op0 = TREE_OPERAND (expr, 0);
2994 enum gimplify_status ret;
2996 switch (TREE_CODE (op0))
2999 /* Check if we are dealing with an expression of the form '&*ptr'.
3000 While the front end folds away '&*ptr' into 'ptr', these
3001 expressions may be generated internally by the compiler (e.g.,
3002 builtins like __builtin_va_end). */
3003 *expr_p = TREE_OPERAND (op0, 0);
3008 /* Fold &a[6] to (&a + 6). */
3009 ret = gimplify_array_ref_to_plus (&TREE_OPERAND (expr, 0),
3012 /* This added an INDIRECT_REF. Fold it away. */
3013 *expr_p = TREE_OPERAND (TREE_OPERAND (expr, 0), 0);
3016 case VIEW_CONVERT_EXPR:
3017 /* Take the address of our operand and then convert it to the type of
3020 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3021 all clear. The impact of this transformation is even less clear. */
3022 *expr_p = fold_convert (TREE_TYPE (expr),
3023 build_fold_addr_expr (TREE_OPERAND (op0, 0)));
3028 /* We use fb_either here because the C frontend sometimes takes
3029 the address of a call that returns a struct. */
3030 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, post_p,
3031 is_gimple_addr_expr_arg, fb_either);
3032 if (ret != GS_ERROR)
3034 /* Make sure TREE_INVARIANT, TREE_CONSTANT, and TREE_SIDE_EFFECTS
3036 recompute_tree_invarant_for_addr_expr (expr);
3038 /* Mark the RHS addressable. */
3039 lang_hooks.mark_addressable (TREE_OPERAND (expr, 0));
3044 /* If the operand is gimplified into a _DECL, mark the address expression
3045 as TREE_INVARIANT. */
3046 if (DECL_P (TREE_OPERAND (expr, 0)))
3047 TREE_INVARIANT (expr) = 1;
3052 /* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple
3053 value; output operands should be a gimple lvalue. */
3055 static enum gimplify_status
3056 gimplify_asm_expr (tree *expr_p, tree *pre_p, tree *post_p)
3058 tree expr = *expr_p;
3059 int noutputs = list_length (ASM_OUTPUTS (expr));
3060 const char **oconstraints
3061 = (const char **) alloca ((noutputs) * sizeof (const char *));
3064 const char *constraint;
3065 bool allows_mem, allows_reg, is_inout;
3066 enum gimplify_status ret, tret;
3069 = resolve_asm_operand_names (ASM_STRING (expr), ASM_OUTPUTS (expr),
3073 for (i = 0, link = ASM_OUTPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3075 oconstraints[i] = constraint
3076 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3078 parse_output_constraint (&constraint, i, 0, 0,
3079 &allows_mem, &allows_reg, &is_inout);
3081 if (!allows_reg && allows_mem)
3082 lang_hooks.mark_addressable (TREE_VALUE (link));
3084 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3085 is_inout ? is_gimple_min_lval : is_gimple_lvalue,
3086 fb_lvalue | fb_mayfail);
3087 if (tret == GS_ERROR)
3089 error ("invalid lvalue in asm output %d", i);
3095 /* An input/output operand. To give the optimizers more
3096 flexibility, split it into separate input and output
3100 size_t constraint_len = strlen (constraint);
3102 /* Turn the in/out constraint into an output constraint. */
3103 char *p = xstrdup (constraint);
3105 TREE_VALUE (TREE_PURPOSE (link)) = build_string (constraint_len, p);
3108 /* And add a matching input constraint. */
3111 sprintf (buf, "%d", i);
3112 input = build_string (strlen (buf), buf);
3115 input = build_string (constraint_len - 1, constraint + 1);
3116 input = build_tree_list (build_tree_list (NULL_TREE, input),
3117 unshare_expr (TREE_VALUE (link)));
3118 ASM_INPUTS (expr) = chainon (ASM_INPUTS (expr), input);
3122 for (link = ASM_INPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3125 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3126 parse_input_constraint (&constraint, 0, 0, noutputs, 0,
3127 oconstraints, &allows_mem, &allows_reg);
3129 /* If the operand is a memory input, it should be an lvalue. */
3130 if (!allows_reg && allows_mem)
3132 lang_hooks.mark_addressable (TREE_VALUE (link));
3133 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3134 is_gimple_lvalue, fb_lvalue | fb_mayfail);
3135 if (tret == GS_ERROR)
3137 error ("memory input %d is not directly addressable", i);
3143 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3144 is_gimple_val, fb_rvalue);
3145 if (tret == GS_ERROR)
3153 /* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding
3154 WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
3155 gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
3156 return to this function.
3158 FIXME should we complexify the prequeue handling instead? Or use flags
3159 for all the cleanups and let the optimizer tighten them up? The current
3160 code seems pretty fragile; it will break on a cleanup within any
3161 non-conditional nesting. But any such nesting would be broken, anyway;
3162 we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
3163 and continues out of it. We can do that at the RTL level, though, so
3164 having an optimizer to tighten up try/finally regions would be a Good
3167 static enum gimplify_status
3168 gimplify_cleanup_point_expr (tree *expr_p, tree *pre_p)
3170 tree_stmt_iterator iter;
3173 tree temp = voidify_wrapper_expr (*expr_p, NULL);
3175 /* We only care about the number of conditions between the innermost
3176 CLEANUP_POINT_EXPR and the cleanup. So save and reset the count. */
3177 int old_conds = gimplify_ctxp->conditions;
3178 gimplify_ctxp->conditions = 0;
3180 body = TREE_OPERAND (*expr_p, 0);
3181 gimplify_to_stmt_list (&body);
3183 gimplify_ctxp->conditions = old_conds;
3185 for (iter = tsi_start (body); !tsi_end_p (iter); )
3187 tree *wce_p = tsi_stmt_ptr (iter);
3190 if (TREE_CODE (wce) == WITH_CLEANUP_EXPR)
3192 if (tsi_one_before_end_p (iter))
3194 tsi_link_before (&iter, TREE_OPERAND (wce, 0), TSI_SAME_STMT);
3202 sl = tsi_split_statement_list_after (&iter);
3203 tfe = build (TRY_FINALLY_EXPR, void_type_node, sl, NULL_TREE);
3204 append_to_statement_list (TREE_OPERAND (wce, 0),
3205 &TREE_OPERAND (tfe, 1));
3207 iter = tsi_start (sl);
3217 append_to_statement_list (body, pre_p);
3227 /* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP
3228 is the cleanup action required. */
3231 gimple_push_cleanup (tree var, tree cleanup, tree *pre_p)
3235 /* Errors can result in improperly nested cleanups. Which results in
3236 confusion when trying to resolve the WITH_CLEANUP_EXPR. */
3237 if (errorcount || sorrycount)
3240 if (gimple_conditional_context ())
3242 /* If we're in a conditional context, this is more complex. We only
3243 want to run the cleanup if we actually ran the initialization that
3244 necessitates it, but we want to run it after the end of the
3245 conditional context. So we wrap the try/finally around the
3246 condition and use a flag to determine whether or not to actually
3247 run the destructor. Thus
3251 becomes (approximately)
3255 if (test) { A::A(temp); flag = 1; val = f(temp); }
3258 if (flag) A::~A(temp);
3263 tree flag = create_tmp_var (boolean_type_node, "cleanup");
3264 tree ffalse = build (MODIFY_EXPR, void_type_node, flag,
3265 boolean_false_node);
3266 tree ftrue = build (MODIFY_EXPR, void_type_node, flag,
3268 cleanup = build (COND_EXPR, void_type_node, flag, cleanup, NULL);
3269 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3270 append_to_statement_list (ffalse, &gimplify_ctxp->conditional_cleanups);
3271 append_to_statement_list (wce, &gimplify_ctxp->conditional_cleanups);
3272 append_to_statement_list (ftrue, pre_p);
3274 /* Because of this manipulation, and the EH edges that jump
3275 threading cannot redirect, the temporary (VAR) will appear
3276 to be used uninitialized. Don't warn. */
3277 TREE_NO_WARNING (var) = 1;
3281 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3282 append_to_statement_list (wce, pre_p);
3285 gimplify_stmt (&TREE_OPERAND (wce, 0));
3288 /* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */
3290 static enum gimplify_status
3291 gimplify_target_expr (tree *expr_p, tree *pre_p, tree *post_p)
3293 tree targ = *expr_p;
3294 tree temp = TARGET_EXPR_SLOT (targ);
3295 tree init = TARGET_EXPR_INITIAL (targ);
3296 enum gimplify_status ret;
3300 /* TARGET_EXPR temps aren't part of the enclosing block, so add it
3301 to the temps list. */
3302 gimple_add_tmp_var (temp);
3304 /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
3305 expression is supposed to initialize the slot. */
3306 if (VOID_TYPE_P (TREE_TYPE (init)))
3307 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, fb_none);
3310 /* Special handling for BIND_EXPR can result in fewer temps. */
3312 if (TREE_CODE (init) == BIND_EXPR)
3313 gimplify_bind_expr (&init, temp, pre_p);
3316 init = build (MODIFY_EXPR, void_type_node, temp, init);
3317 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt,
3321 if (ret == GS_ERROR)
3323 append_to_statement_list (init, pre_p);
3325 /* If needed, push the cleanup for the temp. */
3326 if (TARGET_EXPR_CLEANUP (targ))
3328 gimplify_stmt (&TARGET_EXPR_CLEANUP (targ));
3329 gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ), pre_p);
3332 /* Only expand this once. */
3333 TREE_OPERAND (targ, 3) = init;
3334 TARGET_EXPR_INITIAL (targ) = NULL_TREE;
3336 else if (!DECL_SEEN_IN_BIND_EXPR_P (temp))
3337 /* We should have expanded this before. */
3344 /* Gimplification of expression trees. */
3346 /* Gimplify an expression which appears at statement context; usually, this
3347 means replacing it with a suitably gimple STATEMENT_LIST. */
3350 gimplify_stmt (tree *stmt_p)
3352 gimplify_expr (stmt_p, NULL, NULL, is_gimple_stmt, fb_none);
3355 /* Similarly, but force the result to be a STATEMENT_LIST. */
3358 gimplify_to_stmt_list (tree *stmt_p)
3360 gimplify_stmt (stmt_p);
3362 *stmt_p = alloc_stmt_list ();
3363 else if (TREE_CODE (*stmt_p) != STATEMENT_LIST)
3366 *stmt_p = alloc_stmt_list ();
3367 append_to_statement_list (t, stmt_p);
3372 /* Gimplifies the expression tree pointed by EXPR_P. Return 0 if
3373 gimplification failed.
3375 PRE_P points to the list where side effects that must happen before
3376 EXPR should be stored.
3378 POST_P points to the list where side effects that must happen after
3379 EXPR should be stored, or NULL if there is no suitable list. In
3380 that case, we copy the result to a temporary, emit the
3381 post-effects, and then return the temporary.
3383 GIMPLE_TEST_F points to a function that takes a tree T and
3384 returns nonzero if T is in the GIMPLE form requested by the
3385 caller. The GIMPLE predicates are in tree-gimple.c.
3387 This test is used twice. Before gimplification, the test is
3388 invoked to determine whether *EXPR_P is already gimple enough. If
3389 that fails, *EXPR_P is gimplified according to its code and
3390 GIMPLE_TEST_F is called again. If the test still fails, then a new
3391 temporary variable is created and assigned the value of the
3392 gimplified expression.
3394 FALLBACK tells the function what sort of a temporary we want. If the 1
3395 bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK.
3396 If both are set, either is OK, but an lvalue is preferable.
3398 The return value is either GS_ERROR or GS_ALL_DONE, since this function
3399 iterates until solution. */
3401 enum gimplify_status
3402 gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
3403 bool (* gimple_test_f) (tree), fallback_t fallback)
3406 tree internal_pre = NULL_TREE;
3407 tree internal_post = NULL_TREE;
3409 int is_statement = (pre_p == NULL);
3410 location_t saved_location;
3411 enum gimplify_status ret;
3413 save_expr = *expr_p;
3414 if (save_expr == NULL_TREE)
3417 /* We used to check the predicate here and return immediately if it
3418 succeeds. This is wrong; the design is for gimplification to be
3419 idempotent, and for the predicates to only test for valid forms, not
3420 whether they are fully simplified. */
3422 /* Set up our internal queues if needed. */
3424 pre_p = &internal_pre;
3426 post_p = &internal_post;
3428 saved_location = input_location;
3429 if (save_expr != error_mark_node
3430 && EXPR_HAS_LOCATION (*expr_p))
3431 input_location = EXPR_LOCATION (*expr_p);
3433 /* Loop over the specific gimplifiers until the toplevel node
3434 remains the same. */
3437 /* Strip away as many useless type conversions as possible
3439 STRIP_USELESS_TYPE_CONVERSION (*expr_p);
3441 /* Remember the expr. */
3442 save_expr = *expr_p;
3444 /* Die, die, die, my darling. */
3445 if (save_expr == error_mark_node
3446 || (TREE_TYPE (save_expr)
3447 && TREE_TYPE (save_expr) == error_mark_node))
3453 /* Do any language-specific gimplification. */
3454 ret = lang_hooks.gimplify_expr (expr_p, pre_p, post_p);
3457 if (*expr_p == NULL_TREE)
3459 if (*expr_p != save_expr)
3462 else if (ret != GS_UNHANDLED)
3466 switch (TREE_CODE (*expr_p))
3468 /* First deal with the special cases. */
3470 case POSTINCREMENT_EXPR:
3471 case POSTDECREMENT_EXPR:
3472 case PREINCREMENT_EXPR:
3473 case PREDECREMENT_EXPR:
3474 ret = gimplify_self_mod_expr (expr_p, pre_p, post_p,
3475 fallback != fb_none);
3479 case ARRAY_RANGE_REF:
3483 ret = gimplify_compound_lval (expr_p, pre_p, post_p,
3484 fallback ? fallback : fb_rvalue);
3488 ret = gimplify_cond_expr (expr_p, pre_p, NULL_TREE);
3492 ret = gimplify_call_expr (expr_p, pre_p, fallback != fb_none);
3499 ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none);
3504 ret = gimplify_modify_expr (expr_p, pre_p, post_p,
3505 fallback != fb_none);
3508 case TRUTH_ANDIF_EXPR:
3509 case TRUTH_ORIF_EXPR:
3510 ret = gimplify_boolean_expr (expr_p);
3513 case TRUTH_NOT_EXPR:
3514 TREE_OPERAND (*expr_p, 0)
3515 = gimple_boolify (TREE_OPERAND (*expr_p, 0));
3516 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3517 is_gimple_val, fb_rvalue);
3518 recalculate_side_effects (*expr_p);
3522 ret = gimplify_addr_expr (expr_p, pre_p, post_p);
3526 ret = gimplify_va_arg_expr (expr_p, pre_p, post_p);
3529 case VIEW_CONVERT_EXPR:
3530 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
3531 || fallback == fb_none)
3533 /* Just strip a conversion to void (or in void context) and
3535 *expr_p = TREE_OPERAND (*expr_p, 0);
3539 /* If both types are BLKmode or if one type is of variable size,
3540 convert this into a pointer punning operation. This avoids
3541 copies of large data or making a variable-size temporary.
3543 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3544 all clear. The impact of this transformation is even less
3547 if ((TYPE_MODE (TREE_TYPE (*expr_p)) == BLKmode
3548 && TYPE_MODE (TREE_TYPE (TREE_OPERAND (*expr_p, 0))) == BLKmode)
3549 || !TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (*expr_p)))
3550 || !TREE_CONSTANT (TYPE_SIZE (TREE_TYPE
3551 (TREE_OPERAND (*expr_p,0)))))
3553 tree restype = TREE_TYPE (*expr_p);
3554 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (*expr_p),
3555 fold_convert (build_pointer_type (restype),
3556 build_fold_addr_expr
3557 (TREE_OPERAND (*expr_p, 0))));
3564 if (IS_EMPTY_STMT (*expr_p))
3570 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
3571 || fallback == fb_none)
3573 /* Just strip a conversion to void (or in void context) and
3575 *expr_p = TREE_OPERAND (*expr_p, 0);
3579 ret = gimplify_conversion (expr_p);
3580 if (ret == GS_ERROR)
3582 if (*expr_p != save_expr)
3586 case FIX_TRUNC_EXPR:
3588 case FIX_FLOOR_EXPR:
3589 case FIX_ROUND_EXPR:
3591 /* unary_expr: ... | '(' cast ')' val | ... */
3592 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3593 is_gimple_val, fb_rvalue);
3594 recalculate_side_effects (*expr_p);
3598 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3599 is_gimple_reg, fb_rvalue);
3600 recalculate_side_effects (*expr_p);
3603 /* Constants need not be gimplified. */
3613 *expr_p = DECL_INITIAL (*expr_p);
3617 ret = gimplify_decl_expr (expr_p);
3621 /* FIXME make this a decl. */
3626 ret = gimplify_bind_expr (expr_p, NULL, pre_p);
3630 ret = gimplify_loop_expr (expr_p, pre_p);
3634 ret = gimplify_switch_expr (expr_p, pre_p);
3637 case LABELED_BLOCK_EXPR:
3638 ret = gimplify_labeled_block_expr (expr_p);
3641 case EXIT_BLOCK_EXPR:
3642 ret = gimplify_exit_block_expr (expr_p);
3646 ret = gimplify_exit_expr (expr_p);
3650 /* If the target is not LABEL, then it is a computed jump
3651 and the target needs to be gimplified. */
3652 if (TREE_CODE (GOTO_DESTINATION (*expr_p)) != LABEL_DECL)
3653 ret = gimplify_expr (&GOTO_DESTINATION (*expr_p), pre_p,
3654 NULL, is_gimple_val, fb_rvalue);
3659 #ifdef ENABLE_CHECKING
3660 if (decl_function_context (LABEL_EXPR_LABEL (*expr_p)) != current_function_decl)
3665 case CASE_LABEL_EXPR:
3666 ret = gimplify_case_label_expr (expr_p);
3670 ret = gimplify_return_expr (*expr_p, pre_p);
3674 /* Don't reduce this in place; let gimplify_init_constructor work its
3675 magic. Buf if we're just elaborating this for side effects, just
3676 gimplify any element that has side-effects. */
3677 if (fallback == fb_none)
3679 for (tmp = CONSTRUCTOR_ELTS (*expr_p); tmp;
3680 tmp = TREE_CHAIN (tmp))
3681 if (TREE_SIDE_EFFECTS (TREE_VALUE (tmp)))
3682 gimplify_expr (&TREE_VALUE (tmp), pre_p, post_p,
3683 gimple_test_f, fallback);
3685 *expr_p = NULL_TREE;
3691 /* The following are special cases that are not handled by the
3692 original GIMPLE grammar. */
3694 /* SAVE_EXPR nodes are converted into a GIMPLE identifier and
3697 ret = gimplify_save_expr (expr_p, pre_p, post_p);
3702 enum gimplify_status r0, r1, r2;
3704 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3705 is_gimple_lvalue, fb_either);
3706 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3707 is_gimple_val, fb_rvalue);
3708 r2 = gimplify_expr (&TREE_OPERAND (*expr_p, 2), pre_p, post_p,
3709 is_gimple_val, fb_rvalue);
3710 recalculate_side_effects (*expr_p);
3712 ret = MIN (r0, MIN (r1, r2));
3716 case NON_LVALUE_EXPR:
3717 /* This should have been stripped above. */
3722 ret = gimplify_asm_expr (expr_p, pre_p, post_p);
3725 case TRY_FINALLY_EXPR:
3726 case TRY_CATCH_EXPR:
3727 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 0));
3728 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 1));
3732 case CLEANUP_POINT_EXPR:
3733 ret = gimplify_cleanup_point_expr (expr_p, pre_p);
3737 ret = gimplify_target_expr (expr_p, pre_p, post_p);
3741 gimplify_to_stmt_list (&CATCH_BODY (*expr_p));
3745 case EH_FILTER_EXPR:
3746 gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p));
3752 enum gimplify_status r0, r1;
3753 r0 = gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p), pre_p, post_p,
3754 is_gimple_val, fb_rvalue);
3755 r1 = gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p), pre_p, post_p,
3756 is_gimple_val, fb_rvalue);
3763 ret = gimplify_minimax_expr (expr_p, pre_p, post_p);
3767 /* We get here when taking the address of a label. We mark
3768 the label as "forced"; meaning it can never be removed and
3769 it is a potential target for any computed goto. */
3770 FORCED_LABEL (*expr_p) = 1;
3774 case STATEMENT_LIST:
3775 ret = gimplify_statement_list (expr_p);
3778 case WITH_SIZE_EXPR:
3780 enum gimplify_status r0, r1;
3781 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3782 post_p == &internal_post ? NULL : post_p,
3783 gimple_test_f, fallback);
3784 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3785 is_gimple_val, fb_rvalue);
3790 /* ??? If this is a local variable, and it has not been seen in any
3791 outer BIND_EXPR, then it's probably the result of a duplicate
3792 declaration, for which we've already issued an error. It would
3793 be really nice if the front end wouldn't leak these at all.
3794 Currently the only known culprit is C++ destructors, as seen
3795 in g++.old-deja/g++.jason/binding.C. */
3797 if (!TREE_STATIC (tmp) && !DECL_EXTERNAL (tmp)
3798 && decl_function_context (tmp) == current_function_decl
3799 && !DECL_SEEN_IN_BIND_EXPR_P (tmp))
3801 #ifdef ENABLE_CHECKING
3802 if (!errorcount && !sorrycount)
3812 /* Allow callbacks into the gimplifier during optimization. */
3817 /* If this is a comparison of objects of aggregate type, handle
3818 it specially (by converting to a call to memcmp). It would be
3819 nice to only have to do this for variable-sized objects, but
3820 then we'd have to allow the same nest of reference nodes we
3821 allow for MODIFY_EXPR and that's too complex. */
3822 if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3823 && (AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 1)))))
3824 ret = gimplify_variable_sized_compare (expr_p);
3826 /* If *EXPR_P does not need to be special-cased, handle it
3827 according to its class. */
3828 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '1')
3829 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3830 post_p, is_gimple_val, fb_rvalue);
3831 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '2'
3832 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == '<'
3833 || TREE_CODE (*expr_p) == TRUTH_AND_EXPR
3834 || TREE_CODE (*expr_p) == TRUTH_OR_EXPR
3835 || TREE_CODE (*expr_p) == TRUTH_XOR_EXPR)
3837 enum gimplify_status r0, r1;
3839 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
3840 post_p, is_gimple_val, fb_rvalue);
3841 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p,
3842 post_p, is_gimple_val, fb_rvalue);
3846 else if (TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'd'
3847 || TREE_CODE_CLASS (TREE_CODE (*expr_p)) == 'c')
3853 /* Fail if we don't know how to handle this tree code. */
3856 recalculate_side_effects (*expr_p);
3860 /* If we replaced *expr_p, gimplify again. */
3861 if (ret == GS_OK && (*expr_p == NULL || *expr_p == save_expr))
3864 while (ret == GS_OK);
3866 /* If we encountered an error_mark somewhere nested inside, either
3867 stub out the statement or propagate the error back out. */
3868 if (ret == GS_ERROR)
3875 #ifdef ENABLE_CHECKING
3876 /* This was only valid as a return value from the langhook, which
3877 we handled. Make sure it doesn't escape from any other context. */
3878 if (ret == GS_UNHANDLED)
3882 if (fallback == fb_none && *expr_p && !is_gimple_stmt (*expr_p))
3884 /* We aren't looking for a value, and we don't have a valid
3885 statement. If it doesn't have side-effects, throw it away. */
3886 if (!TREE_SIDE_EFFECTS (*expr_p))
3888 else if (!TREE_THIS_VOLATILE (*expr_p))
3890 /* This is probably a _REF that contains something nested that
3891 has side effects. Recurse through the operands to find it. */
3892 enum tree_code code = TREE_CODE (*expr_p);
3894 if (code == COMPONENT_REF
3895 || code == REALPART_EXPR || code == IMAGPART_EXPR)
3896 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3897 gimple_test_f, fallback);
3898 else if (code == ARRAY_REF || code == ARRAY_RANGE_REF)
3900 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3901 gimple_test_f, fallback);
3902 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3903 gimple_test_f, fallback);
3906 /* Anything else with side-effects
3907 must be converted to a valid statement before we get here. */
3912 else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p)))
3914 /* Historically, the compiler has treated a bare
3915 reference to a volatile lvalue as forcing a load. */
3916 tree tmp = create_tmp_var (TREE_TYPE (*expr_p), "vol");
3917 *expr_p = build (MODIFY_EXPR, TREE_TYPE (tmp), tmp, *expr_p);
3920 /* We can't do anything useful with a volatile reference to
3921 incomplete type, so just throw it away. */
3925 /* If we are gimplifying at the statement level, we're done. Tack
3926 everything together and replace the original statement with the
3928 if (fallback == fb_none || is_statement)
3930 if (internal_pre || internal_post)
3932 append_to_statement_list (*expr_p, &internal_pre);
3933 append_to_statement_list (internal_post, &internal_pre);
3934 annotate_all_with_locus (&internal_pre, input_location);
3935 *expr_p = internal_pre;
3939 else if (TREE_CODE (*expr_p) == STATEMENT_LIST)
3940 annotate_all_with_locus (expr_p, input_location);
3942 annotate_one_with_locus (*expr_p, input_location);
3946 /* Otherwise we're gimplifying a subexpression, so the resulting value is
3949 /* If it's sufficiently simple already, we're done. Unless we are
3950 handling some post-effects internally; if that's the case, we need to
3951 copy into a temp before adding the post-effects to the tree. */
3952 if (!internal_post && (*gimple_test_f) (*expr_p))
3955 /* Otherwise, we need to create a new temporary for the gimplified
3958 /* We can't return an lvalue if we have an internal postqueue. The
3959 object the lvalue refers to would (probably) be modified by the
3960 postqueue; we need to copy the value out first, which means an
3962 if ((fallback & fb_lvalue) && !internal_post
3963 && is_gimple_addr_expr_arg (*expr_p))
3965 /* An lvalue will do. Take the address of the expression, store it
3966 in a temporary, and replace the expression with an INDIRECT_REF of
3968 tmp = build_fold_addr_expr (*expr_p);
3969 gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue);
3970 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp);
3972 else if ((fallback & fb_rvalue) && is_gimple_tmp_rhs (*expr_p))
3974 #if defined ENABLE_CHECKING
3975 if (VOID_TYPE_P (TREE_TYPE (*expr_p)))
3979 /* An rvalue will do. Assign the gimplified expression into a new
3980 temporary TMP and replace the original expression with TMP. */
3982 if (internal_post || (fallback & fb_lvalue))
3983 /* The postqueue might change the value of the expression between
3984 the initialization and use of the temporary, so we can't use a
3985 formal temp. FIXME do we care? */
3986 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
3988 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
3990 else if (fallback & fb_mayfail)
3992 /* If this is an asm statement, and the user asked for the impossible,
3993 don't abort. Fail and let gimplify_asm_expr issue an error. */
3999 fprintf (stderr, "gimplification failed:\n");
4000 print_generic_expr (stderr, *expr_p, 0);
4001 debug_tree (*expr_p);
4005 #if defined ENABLE_CHECKING
4006 /* Make sure the temporary matches our predicate. */
4007 if (!(*gimple_test_f) (*expr_p))
4013 annotate_all_with_locus (&internal_post, input_location);
4014 append_to_statement_list (internal_post, pre_p);
4018 input_location = saved_location;
4022 /* Look through TYPE for variable-sized objects and gimplify each such
4023 size that we find. Add to LIST_P any statements generated. */
4026 gimplify_type_sizes (tree type, tree *list_p)
4030 switch (TREE_CODE (type))
4040 gimplify_one_sizepos (&TYPE_MIN_VALUE (type), list_p);
4041 gimplify_one_sizepos (&TYPE_MAX_VALUE (type), list_p);
4045 /* These anonymous types don't have declarations, so handle them here. */
4046 gimplify_type_sizes (TYPE_DOMAIN (type), list_p);
4051 case QUAL_UNION_TYPE:
4052 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4053 if (TREE_CODE (field) == FIELD_DECL)
4054 gimplify_one_sizepos (&DECL_FIELD_OFFSET (field), list_p);
4061 gimplify_one_sizepos (&TYPE_SIZE (type), list_p);
4062 gimplify_one_sizepos (&TYPE_SIZE_UNIT (type), list_p);
4065 /* Subroutine of the above to gimplify one size or position, *EXPR_P.
4066 We add any required statements to STMT_P. */
4069 gimplify_one_sizepos (tree *expr_p, tree *stmt_p)
4071 /* We don't do anything if the value isn't there, is constant, or contains
4072 A PLACEHOLDER_EXPR. We also don't want to do anything if it's already
4073 a VAR_DECL. If it's a VAR_DECL from another function, the gimplfier
4074 will want to replace it with a new variable, but that will cause problems
4075 if this type is from outside the function. It's OK to have that here. */
4076 if (*expr_p == NULL_TREE || TREE_CONSTANT (*expr_p)
4077 || TREE_CODE (*expr_p) == VAR_DECL
4078 || CONTAINS_PLACEHOLDER_P (*expr_p))
4081 gimplify_expr (expr_p, stmt_p, NULL, is_gimple_val, fb_rvalue);
4084 #ifdef ENABLE_CHECKING
4085 /* Compare types A and B for a "close enough" match. */
4088 cpt_same_type (tree a, tree b)
4090 if (lang_hooks.types_compatible_p (a, b))
4093 /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't
4094 link them together. This routine is intended to catch type errors
4095 that will affect the optimizers, and the optimizers don't add new
4096 dereferences of function pointers, so ignore it. */
4097 if ((TREE_CODE (a) == FUNCTION_TYPE || TREE_CODE (a) == METHOD_TYPE)
4098 && (TREE_CODE (b) == FUNCTION_TYPE || TREE_CODE (b) == METHOD_TYPE))
4101 /* ??? The C FE pushes type qualifiers after the fact into the type of
4102 the element from the type of the array. See build_unary_op's handling
4103 of ADDR_EXPR. This seems wrong -- if we were going to do this, we
4104 should have done it when creating the variable in the first place.
4105 Alternately, why aren't the two array types made variants? */
4106 if (TREE_CODE (a) == ARRAY_TYPE && TREE_CODE (b) == ARRAY_TYPE)
4107 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4109 /* And because of those, we have to recurse down through pointers. */
4110 if (POINTER_TYPE_P (a) && POINTER_TYPE_P (b))
4111 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4116 /* Check for some cases of the front end missing cast expressions.
4117 The type of a dereference should correspond to the pointer type;
4118 similarly the type of an address should match its object. */
4121 check_pointer_types_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
4122 void *data ATTRIBUTE_UNUSED)
4125 tree ptype, otype, dtype;
4127 switch (TREE_CODE (t))
4131 otype = TREE_TYPE (t);
4132 ptype = TREE_TYPE (TREE_OPERAND (t, 0));
4133 dtype = TREE_TYPE (ptype);
4134 if (!cpt_same_type (otype, dtype))
4139 ptype = TREE_TYPE (t);
4140 otype = TREE_TYPE (TREE_OPERAND (t, 0));
4141 dtype = TREE_TYPE (ptype);
4142 if (!cpt_same_type (otype, dtype))
4144 /* &array is allowed to produce a pointer to the element, rather than
4145 a pointer to the array type. We must allow this in order to
4146 properly represent assigning the address of an array in C into
4147 pointer to the element type. */
4148 if (TREE_CODE (otype) == ARRAY_TYPE
4149 && POINTER_TYPE_P (ptype)
4150 && cpt_same_type (TREE_TYPE (otype), dtype))
4165 /* Gimplify the body of statements pointed by BODY_P. FNDECL is the
4166 function decl containing BODY. */
4169 gimplify_body (tree *body_p, tree fndecl)
4171 location_t saved_location = input_location;
4174 timevar_push (TV_TREE_GIMPLIFY);
4175 push_gimplify_context ();
4177 /* Unshare most shared trees in the body and in that of any nested functions.
4178 It would seem we don't have to do this for nested functions because
4179 they are supposed to be output and then the outer function gimplified
4180 first, but the g++ front end doesn't always do it that way. */
4181 unshare_body (body_p, fndecl);
4182 unvisit_body (body_p, fndecl);
4184 /* Make sure input_location isn't set to something wierd. */
4185 input_location = DECL_SOURCE_LOCATION (fndecl);
4187 /* Gimplify the function's body. */
4188 gimplify_stmt (body_p);
4191 /* Unshare again, in case gimplification was sloppy. */
4192 unshare_all_trees (body);
4195 body = alloc_stmt_list ();
4196 else if (TREE_CODE (body) == STATEMENT_LIST)
4198 tree t = expr_only (*body_p);
4203 /* If there isn't an outer BIND_EXPR, add one. */
4204 if (TREE_CODE (body) != BIND_EXPR)
4206 tree b = build (BIND_EXPR, void_type_node, NULL_TREE,
4207 NULL_TREE, NULL_TREE);
4208 TREE_SIDE_EFFECTS (b) = 1;
4209 append_to_statement_list_force (body, &BIND_EXPR_BODY (b));
4214 pop_gimplify_context (body);
4216 #ifdef ENABLE_CHECKING
4217 walk_tree (body_p, check_pointer_types_r, NULL, NULL);
4220 timevar_pop (TV_TREE_GIMPLIFY);
4221 input_location = saved_location;
4224 /* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL
4225 node for the function we want to gimplify. */
4228 gimplify_function_tree (tree fndecl)
4232 oldfn = current_function_decl;
4233 current_function_decl = fndecl;
4235 gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl);
4237 /* If we're instrumenting function entry/exit, then prepend the call to
4238 the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
4239 catch the exit hook. */
4240 /* ??? Add some way to ignore exceptions for this TFE. */
4241 if (flag_instrument_function_entry_exit
4242 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl))
4246 tf = build (TRY_FINALLY_EXPR, void_type_node, NULL, NULL);
4247 TREE_SIDE_EFFECTS (tf) = 1;
4248 x = DECL_SAVED_TREE (fndecl);
4249 append_to_statement_list (x, &TREE_OPERAND (tf, 0));
4250 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_EXIT];
4251 x = build_function_call_expr (x, NULL);
4252 append_to_statement_list (x, &TREE_OPERAND (tf, 1));
4254 bind = build (BIND_EXPR, void_type_node, NULL, NULL, NULL);
4255 TREE_SIDE_EFFECTS (bind) = 1;
4256 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_ENTER];
4257 x = build_function_call_expr (x, NULL);
4258 append_to_statement_list (x, &BIND_EXPR_BODY (bind));
4259 append_to_statement_list (tf, &BIND_EXPR_BODY (bind));
4261 DECL_SAVED_TREE (fndecl) = bind;
4264 current_function_decl = oldfn;
4267 #include "gt-gimplify.h"