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, 2005 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, 51 Franklin Street, Fifth Floor, Boston, MA
26 #include "coretypes.h"
31 #include "tree-gimple.h"
32 #include "tree-inline.h"
33 #include "diagnostic.h"
34 #include "langhooks.h"
35 #include "langhooks-def.h"
36 #include "tree-flow.h"
50 static struct gimplify_ctx
52 tree current_bind_expr;
54 tree conditional_cleanups;
57 VEC(tree,heap) *case_labels;
58 /* The formal temporary table. Should this be persistent? */
66 /* Formal (expression) temporary table handling: Multiple occurrences of
67 the same scalar expression are evaluated into the same temporary. */
69 typedef struct gimple_temp_hash_elt
72 tree temp; /* Value */
75 /* Forward declarations. */
76 static enum gimplify_status gimplify_compound_expr (tree *, tree *, bool);
77 #ifdef ENABLE_CHECKING
78 static bool cpt_same_type (tree a, tree b);
82 /* Return a hash value for a formal temporary table entry. */
85 gimple_tree_hash (const void *p)
87 tree t = ((const elt_t *) p)->val;
88 return iterative_hash_expr (t, 0);
91 /* Compare two formal temporary table entries. */
94 gimple_tree_eq (const void *p1, const void *p2)
96 tree t1 = ((const elt_t *) p1)->val;
97 tree t2 = ((const elt_t *) p2)->val;
98 enum tree_code code = TREE_CODE (t1);
100 if (TREE_CODE (t2) != code
101 || TREE_TYPE (t1) != TREE_TYPE (t2))
104 if (!operand_equal_p (t1, t2, 0))
107 /* Only allow them to compare equal if they also hash equal; otherwise
108 results are nondeterminate, and we fail bootstrap comparison. */
109 gcc_assert (gimple_tree_hash (p1) == gimple_tree_hash (p2));
114 /* Set up a context for the gimplifier. */
117 push_gimplify_context (void)
119 gcc_assert (!gimplify_ctxp);
121 = (struct gimplify_ctx *) xcalloc (1, sizeof (struct gimplify_ctx));
123 gimplify_ctxp->temp_htab
124 = htab_create (1000, gimple_tree_hash, gimple_tree_eq, free);
126 gimplify_ctxp->temp_htab = NULL;
129 /* Tear down a context for the gimplifier. If BODY is non-null, then
130 put the temporaries into the outer BIND_EXPR. Otherwise, put them
131 in the unexpanded_var_list. */
134 pop_gimplify_context (tree body)
138 gcc_assert (gimplify_ctxp && !gimplify_ctxp->current_bind_expr);
140 for (t = gimplify_ctxp->temps; t ; t = TREE_CHAIN (t))
141 DECL_GIMPLE_FORMAL_TEMP_P (t) = 0;
144 declare_tmp_vars (gimplify_ctxp->temps, body);
146 record_vars (gimplify_ctxp->temps);
149 if (!quiet_flag && optimize)
150 fprintf (stderr, " collisions: %f ",
151 htab_collisions (gimplify_ctxp->temp_htab));
155 htab_delete (gimplify_ctxp->temp_htab);
156 free (gimplify_ctxp);
157 gimplify_ctxp = NULL;
161 gimple_push_bind_expr (tree bind)
163 TREE_CHAIN (bind) = gimplify_ctxp->current_bind_expr;
164 gimplify_ctxp->current_bind_expr = bind;
168 gimple_pop_bind_expr (void)
170 gimplify_ctxp->current_bind_expr
171 = TREE_CHAIN (gimplify_ctxp->current_bind_expr);
175 gimple_current_bind_expr (void)
177 return gimplify_ctxp->current_bind_expr;
180 /* Returns true iff there is a COND_EXPR between us and the innermost
181 CLEANUP_POINT_EXPR. This info is used by gimple_push_cleanup. */
184 gimple_conditional_context (void)
186 return gimplify_ctxp->conditions > 0;
189 /* Note that we've entered a COND_EXPR. */
192 gimple_push_condition (void)
194 #ifdef ENABLE_CHECKING
195 if (gimplify_ctxp->conditions == 0)
196 gcc_assert (!gimplify_ctxp->conditional_cleanups);
198 ++(gimplify_ctxp->conditions);
201 /* Note that we've left a COND_EXPR. If we're back at unconditional scope
202 now, add any conditional cleanups we've seen to the prequeue. */
205 gimple_pop_condition (tree *pre_p)
207 int conds = --(gimplify_ctxp->conditions);
209 gcc_assert (conds >= 0);
212 append_to_statement_list (gimplify_ctxp->conditional_cleanups, pre_p);
213 gimplify_ctxp->conditional_cleanups = NULL_TREE;
217 /* A subroutine of append_to_statement_list{,_force}. T is not NULL. */
220 append_to_statement_list_1 (tree t, tree *list_p)
223 tree_stmt_iterator i;
227 if (t && TREE_CODE (t) == STATEMENT_LIST)
232 *list_p = list = alloc_stmt_list ();
236 tsi_link_after (&i, t, TSI_CONTINUE_LINKING);
239 /* Add T to the end of the list container pointed by LIST_P.
240 If T is an expression with no effects, it is ignored. */
243 append_to_statement_list (tree t, tree *list_p)
245 if (t && TREE_SIDE_EFFECTS (t))
246 append_to_statement_list_1 (t, list_p);
249 /* Similar, but the statement is always added, regardless of side effects. */
252 append_to_statement_list_force (tree t, tree *list_p)
255 append_to_statement_list_1 (t, list_p);
258 /* Both gimplify the statement T and append it to LIST_P. */
261 gimplify_and_add (tree t, tree *list_p)
264 append_to_statement_list (t, list_p);
267 /* Strip off a legitimate source ending from the input string NAME of
268 length LEN. Rather than having to know the names used by all of
269 our front ends, we strip off an ending of a period followed by
270 up to five characters. (Java uses ".class".) */
273 remove_suffix (char *name, int len)
277 for (i = 2; i < 8 && len > i; i++)
279 if (name[len - i] == '.')
281 name[len - i] = '\0';
287 /* Create a nameless artificial label and put it in the current function
288 context. Returns the newly created label. */
291 create_artificial_label (void)
293 tree lab = build_decl (LABEL_DECL, NULL_TREE, void_type_node);
295 DECL_ARTIFICIAL (lab) = 1;
296 DECL_IGNORED_P (lab) = 1;
297 DECL_CONTEXT (lab) = current_function_decl;
301 /* Create a new temporary name with PREFIX. Returns an identifier. */
303 static GTY(()) unsigned int tmp_var_id_num;
306 create_tmp_var_name (const char *prefix)
312 char *preftmp = ASTRDUP (prefix);
314 remove_suffix (preftmp, strlen (preftmp));
318 ASM_FORMAT_PRIVATE_NAME (tmp_name, prefix ? prefix : "T", tmp_var_id_num++);
319 return get_identifier (tmp_name);
323 /* Create a new temporary variable declaration of type TYPE.
324 Does NOT push it into the current binding. */
327 create_tmp_var_raw (tree type, const char *prefix)
332 /* Make the type of the variable writable. */
333 new_type = build_type_variant (type, 0, 0);
334 TYPE_ATTRIBUTES (new_type) = TYPE_ATTRIBUTES (type);
336 tmp_var = build_decl (VAR_DECL, prefix ? create_tmp_var_name (prefix) : NULL,
339 /* The variable was declared by the compiler. */
340 DECL_ARTIFICIAL (tmp_var) = 1;
341 /* And we don't want debug info for it. */
342 DECL_IGNORED_P (tmp_var) = 1;
344 /* Make the variable writable. */
345 TREE_READONLY (tmp_var) = 0;
347 DECL_EXTERNAL (tmp_var) = 0;
348 TREE_STATIC (tmp_var) = 0;
349 TREE_USED (tmp_var) = 1;
354 /* Create a new temporary variable declaration of type TYPE. DOES push the
355 variable into the current binding. Further, assume that this is called
356 only from gimplification or optimization, at which point the creation of
357 certain types are bugs. */
360 create_tmp_var (tree type, const char *prefix)
364 /* We don't allow types that are addressable (meaning we can't make copies),
365 incomplete, or of variable size. */
366 gcc_assert (!TREE_ADDRESSABLE (type)
367 && COMPLETE_TYPE_P (type)
368 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST);
370 tmp_var = create_tmp_var_raw (type, prefix);
371 gimple_add_tmp_var (tmp_var);
375 /* Given a tree, try to return a useful variable name that we can use
376 to prefix a temporary that is being assigned the value of the tree.
377 I.E. given <temp> = &A, return A. */
385 STRIP_NOPS (stripped_decl);
386 if (DECL_P (stripped_decl) && DECL_NAME (stripped_decl))
387 return IDENTIFIER_POINTER (DECL_NAME (stripped_decl));
390 switch (TREE_CODE (stripped_decl))
393 return get_name (TREE_OPERAND (stripped_decl, 0));
401 /* Create a temporary with a name derived from VAL. Subroutine of
402 lookup_tmp_var; nobody else should call this function. */
405 create_tmp_from_val (tree val)
407 return create_tmp_var (TREE_TYPE (val), get_name (val));
410 /* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse
411 an existing expression temporary. */
414 lookup_tmp_var (tree val, bool is_formal)
418 /* If not optimizing, never really reuse a temporary. local-alloc
419 won't allocate any variable that is used in more than one basic
420 block, which means it will go into memory, causing much extra
421 work in reload and final and poorer code generation, outweighing
422 the extra memory allocation here. */
423 if (!optimize || !is_formal || TREE_SIDE_EFFECTS (val))
424 ret = create_tmp_from_val (val);
431 slot = htab_find_slot (gimplify_ctxp->temp_htab, (void *)&elt, INSERT);
434 elt_p = xmalloc (sizeof (*elt_p));
436 elt_p->temp = ret = create_tmp_from_val (val);
437 *slot = (void *) elt_p;
441 elt_p = (elt_t *) *slot;
447 DECL_GIMPLE_FORMAL_TEMP_P (ret) = 1;
452 /* Returns a formal temporary variable initialized with VAL. PRE_P is as
453 in gimplify_expr. Only use this function if:
455 1) The value of the unfactored expression represented by VAL will not
456 change between the initialization and use of the temporary, and
457 2) The temporary will not be otherwise modified.
459 For instance, #1 means that this is inappropriate for SAVE_EXPR temps,
460 and #2 means it is inappropriate for && temps.
462 For other cases, use get_initialized_tmp_var instead. */
465 internal_get_tmp_var (tree val, tree *pre_p, tree *post_p, bool is_formal)
469 gimplify_expr (&val, pre_p, post_p, is_gimple_formal_tmp_rhs, fb_rvalue);
471 t = lookup_tmp_var (val, is_formal);
473 if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE)
474 DECL_COMPLEX_GIMPLE_REG_P (t) = 1;
476 mod = build (MODIFY_EXPR, TREE_TYPE (t), t, val);
478 if (EXPR_HAS_LOCATION (val))
479 SET_EXPR_LOCUS (mod, EXPR_LOCUS (val));
481 SET_EXPR_LOCATION (mod, input_location);
483 /* gimplify_modify_expr might want to reduce this further. */
484 gimplify_and_add (mod, pre_p);
486 /* If we're gimplifying into ssa, gimplify_modify_expr will have
487 given our temporary an ssa name. Find and return it. */
488 if (gimplify_ctxp->into_ssa)
489 t = TREE_OPERAND (mod, 0);
495 get_formal_tmp_var (tree val, tree *pre_p)
497 return internal_get_tmp_var (val, pre_p, NULL, true);
500 /* Returns a temporary variable initialized with VAL. PRE_P and POST_P
501 are as in gimplify_expr. */
504 get_initialized_tmp_var (tree val, tree *pre_p, tree *post_p)
506 return internal_get_tmp_var (val, pre_p, post_p, false);
509 /* Declares all the variables in VARS in SCOPE. */
512 declare_tmp_vars (tree vars, tree scope)
519 /* C99 mode puts the default 'return 0;' for main outside the outer
520 braces. So drill down until we find an actual scope. */
521 while (TREE_CODE (scope) == COMPOUND_EXPR)
522 scope = TREE_OPERAND (scope, 0);
524 gcc_assert (TREE_CODE (scope) == BIND_EXPR);
526 temps = nreverse (last);
527 TREE_CHAIN (last) = BIND_EXPR_VARS (scope);
528 BIND_EXPR_VARS (scope) = temps;
533 gimple_add_tmp_var (tree tmp)
535 gcc_assert (!TREE_CHAIN (tmp) && !DECL_SEEN_IN_BIND_EXPR_P (tmp));
537 DECL_CONTEXT (tmp) = current_function_decl;
538 DECL_SEEN_IN_BIND_EXPR_P (tmp) = 1;
542 TREE_CHAIN (tmp) = gimplify_ctxp->temps;
543 gimplify_ctxp->temps = tmp;
548 declare_tmp_vars (tmp, DECL_SAVED_TREE (current_function_decl));
551 /* Determines whether to assign a locus to the statement STMT. */
554 should_carry_locus_p (tree stmt)
556 /* Don't emit a line note for a label. We particularly don't want to
557 emit one for the break label, since it doesn't actually correspond
558 to the beginning of the loop/switch. */
559 if (TREE_CODE (stmt) == LABEL_EXPR)
562 /* Do not annotate empty statements, since it confuses gcov. */
563 if (!TREE_SIDE_EFFECTS (stmt))
570 annotate_one_with_locus (tree t, location_t locus)
572 if (EXPR_P (t) && ! EXPR_HAS_LOCATION (t) && should_carry_locus_p (t))
573 SET_EXPR_LOCATION (t, locus);
577 annotate_all_with_locus (tree *stmt_p, location_t locus)
579 tree_stmt_iterator i;
584 for (i = tsi_start (*stmt_p); !tsi_end_p (i); tsi_next (&i))
586 tree t = tsi_stmt (i);
588 /* Assuming we've already been gimplified, we shouldn't
589 see nested chaining constructs anymore. */
590 gcc_assert (TREE_CODE (t) != STATEMENT_LIST
591 && TREE_CODE (t) != COMPOUND_EXPR);
593 annotate_one_with_locus (t, locus);
597 /* Similar to copy_tree_r() but do not copy SAVE_EXPR or TARGET_EXPR nodes.
598 These nodes model computations that should only be done once. If we
599 were to unshare something like SAVE_EXPR(i++), the gimplification
600 process would create wrong code. */
603 mostly_copy_tree_r (tree *tp, int *walk_subtrees, void *data)
605 enum tree_code code = TREE_CODE (*tp);
606 /* Don't unshare types, decls, constants and SAVE_EXPR nodes. */
607 if (TREE_CODE_CLASS (code) == tcc_type
608 || TREE_CODE_CLASS (code) == tcc_declaration
609 || TREE_CODE_CLASS (code) == tcc_constant
610 || code == SAVE_EXPR || code == TARGET_EXPR
611 /* We can't do anything sensible with a BLOCK used as an expression,
612 but we also can't just die when we see it because of non-expression
613 uses. So just avert our eyes and cross our fingers. Silly Java. */
618 gcc_assert (code != BIND_EXPR);
619 copy_tree_r (tp, walk_subtrees, data);
625 /* Callback for walk_tree to unshare most of the shared trees rooted at
626 *TP. If *TP has been visited already (i.e., TREE_VISITED (*TP) == 1),
627 then *TP is deep copied by calling copy_tree_r.
629 This unshares the same trees as copy_tree_r with the exception of
630 SAVE_EXPR nodes. These nodes model computations that should only be
631 done once. If we were to unshare something like SAVE_EXPR(i++), the
632 gimplification process would create wrong code. */
635 copy_if_shared_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
636 void *data ATTRIBUTE_UNUSED)
639 enum tree_code code = TREE_CODE (t);
641 /* Skip types, decls, and constants. But we do want to look at their
642 types and the bounds of types. Mark them as visited so we properly
643 unmark their subtrees on the unmark pass. If we've already seen them,
644 don't look down further. */
645 if (TREE_CODE_CLASS (code) == tcc_type
646 || TREE_CODE_CLASS (code) == tcc_declaration
647 || TREE_CODE_CLASS (code) == tcc_constant)
649 if (TREE_VISITED (t))
652 TREE_VISITED (t) = 1;
655 /* If this node has been visited already, unshare it and don't look
657 else if (TREE_VISITED (t))
659 walk_tree (tp, mostly_copy_tree_r, NULL, NULL);
663 /* Otherwise, mark the tree as visited and keep looking. */
665 TREE_VISITED (t) = 1;
671 unmark_visited_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
672 void *data ATTRIBUTE_UNUSED)
674 if (TREE_VISITED (*tp))
675 TREE_VISITED (*tp) = 0;
682 /* Unshare all the trees in BODY_P, a pointer into the body of FNDECL, and the
683 bodies of any nested functions if we are unsharing the entire body of
687 unshare_body (tree *body_p, tree fndecl)
689 struct cgraph_node *cgn = cgraph_node (fndecl);
691 walk_tree (body_p, copy_if_shared_r, NULL, NULL);
692 if (body_p == &DECL_SAVED_TREE (fndecl))
693 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
694 unshare_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
697 /* Likewise, but mark all trees as not visited. */
700 unvisit_body (tree *body_p, tree fndecl)
702 struct cgraph_node *cgn = cgraph_node (fndecl);
704 walk_tree (body_p, unmark_visited_r, NULL, NULL);
705 if (body_p == &DECL_SAVED_TREE (fndecl))
706 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
707 unvisit_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
710 /* Unshare T and all the trees reached from T via TREE_CHAIN. */
713 unshare_all_trees (tree t)
715 walk_tree (&t, copy_if_shared_r, NULL, NULL);
716 walk_tree (&t, unmark_visited_r, NULL, NULL);
719 /* Unconditionally make an unshared copy of EXPR. This is used when using
720 stored expressions which span multiple functions, such as BINFO_VTABLE,
721 as the normal unsharing process can't tell that they're shared. */
724 unshare_expr (tree expr)
726 walk_tree (&expr, mostly_copy_tree_r, NULL, NULL);
730 /* A terser interface for building a representation of an exception
734 gimple_build_eh_filter (tree body, tree allowed, tree failure)
738 /* FIXME should the allowed types go in TREE_TYPE? */
739 t = build (EH_FILTER_EXPR, void_type_node, allowed, NULL_TREE);
740 append_to_statement_list (failure, &EH_FILTER_FAILURE (t));
742 t = build (TRY_CATCH_EXPR, void_type_node, NULL_TREE, t);
743 append_to_statement_list (body, &TREE_OPERAND (t, 0));
749 /* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
750 contain statements and have a value. Assign its value to a temporary
751 and give it void_type_node. Returns the temporary, or NULL_TREE if
752 WRAPPER was already void. */
755 voidify_wrapper_expr (tree wrapper, tree temp)
757 if (!VOID_TYPE_P (TREE_TYPE (wrapper)))
759 tree *p, sub = wrapper;
762 /* Set p to point to the body of the wrapper. */
763 switch (TREE_CODE (sub))
766 /* For a BIND_EXPR, the body is operand 1. */
767 p = &BIND_EXPR_BODY (sub);
771 p = &TREE_OPERAND (sub, 0);
775 /* Advance to the last statement. Set all container types to void. */
776 if (TREE_CODE (*p) == STATEMENT_LIST)
778 tree_stmt_iterator i = tsi_last (*p);
779 p = tsi_end_p (i) ? NULL : tsi_stmt_ptr (i);
783 for (; TREE_CODE (*p) == COMPOUND_EXPR; p = &TREE_OPERAND (*p, 1))
785 TREE_SIDE_EFFECTS (*p) = 1;
786 TREE_TYPE (*p) = void_type_node;
790 if (p == NULL || IS_EMPTY_STMT (*p))
792 /* Look through exception handling. */
793 else if (TREE_CODE (*p) == TRY_FINALLY_EXPR
794 || TREE_CODE (*p) == TRY_CATCH_EXPR)
799 /* The C++ frontend already did this for us. */
800 else if (TREE_CODE (*p) == INIT_EXPR
801 || TREE_CODE (*p) == TARGET_EXPR)
802 temp = TREE_OPERAND (*p, 0);
803 /* If we're returning a dereference, move the dereference
804 outside the wrapper. */
805 else if (TREE_CODE (*p) == INDIRECT_REF)
807 tree ptr = TREE_OPERAND (*p, 0);
808 temp = create_tmp_var (TREE_TYPE (ptr), "retval");
809 *p = build (MODIFY_EXPR, TREE_TYPE (ptr), temp, ptr);
810 temp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (temp)), temp);
811 /* If this is a BIND_EXPR for a const inline function, it might not
812 have TREE_SIDE_EFFECTS set. That is no longer accurate. */
813 TREE_SIDE_EFFECTS (wrapper) = 1;
818 temp = create_tmp_var (TREE_TYPE (wrapper), "retval");
819 *p = build (MODIFY_EXPR, TREE_TYPE (temp), temp, *p);
820 TREE_SIDE_EFFECTS (wrapper) = 1;
823 TREE_TYPE (wrapper) = void_type_node;
830 /* Prepare calls to builtins to SAVE and RESTORE the stack as well as
831 a temporary through which they communicate. */
834 build_stack_save_restore (tree *save, tree *restore)
836 tree save_call, tmp_var;
839 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_SAVE],
841 tmp_var = create_tmp_var (ptr_type_node, "saved_stack");
843 *save = build (MODIFY_EXPR, ptr_type_node, tmp_var, save_call);
845 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_RESTORE],
846 tree_cons (NULL_TREE, tmp_var, NULL_TREE));
849 /* Gimplify a BIND_EXPR. Just voidify and recurse. */
851 static enum gimplify_status
852 gimplify_bind_expr (tree *expr_p, tree temp, tree *pre_p)
854 tree bind_expr = *expr_p;
855 bool old_save_stack = gimplify_ctxp->save_stack;
858 temp = voidify_wrapper_expr (bind_expr, temp);
860 /* Mark variables seen in this bind expr. */
861 for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t))
863 if (TREE_CODE (t) == VAR_DECL)
864 DECL_SEEN_IN_BIND_EXPR_P (t) = 1;
866 /* Preliminarily mark non-addressed complex variables as eligible
867 for promotion to gimple registers. We'll transform their uses
869 if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE
870 && !TREE_THIS_VOLATILE (t)
871 && (TREE_CODE (t) == VAR_DECL && !DECL_HARD_REGISTER (t))
872 && !needs_to_live_in_memory (t))
873 DECL_COMPLEX_GIMPLE_REG_P (t) = 1;
876 gimple_push_bind_expr (bind_expr);
877 gimplify_ctxp->save_stack = false;
879 gimplify_to_stmt_list (&BIND_EXPR_BODY (bind_expr));
881 if (gimplify_ctxp->save_stack)
883 tree stack_save, stack_restore;
885 /* Save stack on entry and restore it on exit. Add a try_finally
886 block to achieve this. Note that mudflap depends on the
887 format of the emitted code: see mx_register_decls(). */
888 build_stack_save_restore (&stack_save, &stack_restore);
890 t = build (TRY_FINALLY_EXPR, void_type_node,
891 BIND_EXPR_BODY (bind_expr), NULL_TREE);
892 append_to_statement_list (stack_restore, &TREE_OPERAND (t, 1));
894 BIND_EXPR_BODY (bind_expr) = NULL_TREE;
895 append_to_statement_list (stack_save, &BIND_EXPR_BODY (bind_expr));
896 append_to_statement_list (t, &BIND_EXPR_BODY (bind_expr));
899 gimplify_ctxp->save_stack = old_save_stack;
900 gimple_pop_bind_expr ();
905 append_to_statement_list (bind_expr, pre_p);
912 /* Gimplify a RETURN_EXPR. If the expression to be returned is not a
913 GIMPLE value, it is assigned to a new temporary and the statement is
914 re-written to return the temporary.
916 PRE_P points to the list where side effects that must happen before
917 STMT should be stored. */
919 static enum gimplify_status
920 gimplify_return_expr (tree stmt, tree *pre_p)
922 tree ret_expr = TREE_OPERAND (stmt, 0);
923 tree result_decl, result;
925 if (!ret_expr || TREE_CODE (ret_expr) == RESULT_DECL
926 || ret_expr == error_mark_node)
929 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
930 result_decl = NULL_TREE;
933 result_decl = TREE_OPERAND (ret_expr, 0);
934 if (TREE_CODE (result_decl) == INDIRECT_REF)
935 /* See through a return by reference. */
936 result_decl = TREE_OPERAND (result_decl, 0);
938 gcc_assert ((TREE_CODE (ret_expr) == MODIFY_EXPR
939 || TREE_CODE (ret_expr) == INIT_EXPR)
940 && TREE_CODE (result_decl) == RESULT_DECL);
943 /* If aggregate_value_p is true, then we can return the bare RESULT_DECL.
944 Recall that aggregate_value_p is FALSE for any aggregate type that is
945 returned in registers. If we're returning values in registers, then
946 we don't want to extend the lifetime of the RESULT_DECL, particularly
947 across another call. In addition, for those aggregates for which
948 hard_function_value generates a PARALLEL, we'll die during normal
949 expansion of structure assignments; there's special code in expand_return
950 to handle this case that does not exist in expand_expr. */
952 || aggregate_value_p (result_decl, TREE_TYPE (current_function_decl)))
953 result = result_decl;
954 else if (gimplify_ctxp->return_temp)
955 result = gimplify_ctxp->return_temp;
958 result = create_tmp_var (TREE_TYPE (result_decl), NULL);
960 /* ??? With complex control flow (usually involving abnormal edges),
961 we can wind up warning about an uninitialized value for this. Due
962 to how this variable is constructed and initialized, this is never
963 true. Give up and never warn. */
964 TREE_NO_WARNING (result) = 1;
966 gimplify_ctxp->return_temp = result;
969 /* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
970 Then gimplify the whole thing. */
971 if (result != result_decl)
972 TREE_OPERAND (ret_expr, 0) = result;
974 gimplify_and_add (TREE_OPERAND (stmt, 0), pre_p);
976 /* If we didn't use a temporary, then the result is just the result_decl.
977 Otherwise we need a simple copy. This should already be gimple. */
978 if (result == result_decl)
981 ret_expr = build (MODIFY_EXPR, TREE_TYPE (result), result_decl, result);
982 TREE_OPERAND (stmt, 0) = ret_expr;
987 /* Gimplifies a DECL_EXPR node *STMT_P by making any necessary allocation
988 and initialization explicit. */
990 static enum gimplify_status
991 gimplify_decl_expr (tree *stmt_p)
994 tree decl = DECL_EXPR_DECL (stmt);
998 if (TREE_TYPE (decl) == error_mark_node)
1001 if ((TREE_CODE (decl) == TYPE_DECL
1002 || TREE_CODE (decl) == VAR_DECL)
1003 && !TYPE_SIZES_GIMPLIFIED (TREE_TYPE (decl)))
1004 gimplify_type_sizes (TREE_TYPE (decl), stmt_p);
1006 if (TREE_CODE (decl) == VAR_DECL && !DECL_EXTERNAL (decl))
1008 tree init = DECL_INITIAL (decl);
1010 if (!TREE_CONSTANT (DECL_SIZE (decl)))
1012 /* This is a variable-sized decl. Simplify its size and mark it
1013 for deferred expansion. Note that mudflap depends on the format
1014 of the emitted code: see mx_register_decls(). */
1015 tree t, args, addr, ptr_type;
1017 gimplify_one_sizepos (&DECL_SIZE (decl), stmt_p);
1018 gimplify_one_sizepos (&DECL_SIZE_UNIT (decl), stmt_p);
1020 /* All occurrences of this decl in final gimplified code will be
1021 replaced by indirection. Setting DECL_VALUE_EXPR does two
1022 things: First, it lets the rest of the gimplifier know what
1023 replacement to use. Second, it lets the debug info know
1024 where to find the value. */
1025 ptr_type = build_pointer_type (TREE_TYPE (decl));
1026 addr = create_tmp_var (ptr_type, get_name (decl));
1027 DECL_IGNORED_P (addr) = 0;
1028 t = build_fold_indirect_ref (addr);
1029 SET_DECL_VALUE_EXPR (decl, t);
1030 DECL_HAS_VALUE_EXPR_P (decl) = 1;
1032 args = tree_cons (NULL, DECL_SIZE_UNIT (decl), NULL);
1033 t = built_in_decls[BUILT_IN_ALLOCA];
1034 t = build_function_call_expr (t, args);
1035 t = fold_convert (ptr_type, t);
1036 t = build2 (MODIFY_EXPR, void_type_node, addr, t);
1038 gimplify_and_add (t, stmt_p);
1040 /* Indicate that we need to restore the stack level when the
1041 enclosing BIND_EXPR is exited. */
1042 gimplify_ctxp->save_stack = true;
1045 if (init && init != error_mark_node)
1047 if (!TREE_STATIC (decl))
1049 DECL_INITIAL (decl) = NULL_TREE;
1050 init = build (MODIFY_EXPR, void_type_node, decl, init);
1051 gimplify_and_add (init, stmt_p);
1054 /* We must still examine initializers for static variables
1055 as they may contain a label address. */
1056 walk_tree (&init, force_labels_r, NULL, NULL);
1059 /* This decl isn't mentioned in the enclosing block, so add it to the
1060 list of temps. FIXME it seems a bit of a kludge to say that
1061 anonymous artificial vars aren't pushed, but everything else is. */
1062 if (DECL_ARTIFICIAL (decl) && DECL_NAME (decl) == NULL_TREE)
1063 gimple_add_tmp_var (decl);
1069 /* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body
1070 and replacing the LOOP_EXPR with goto, but if the loop contains an
1071 EXIT_EXPR, we need to append a label for it to jump to. */
1073 static enum gimplify_status
1074 gimplify_loop_expr (tree *expr_p, tree *pre_p)
1076 tree saved_label = gimplify_ctxp->exit_label;
1077 tree start_label = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
1078 tree jump_stmt = build_and_jump (&LABEL_EXPR_LABEL (start_label));
1080 append_to_statement_list (start_label, pre_p);
1082 gimplify_ctxp->exit_label = NULL_TREE;
1084 gimplify_and_add (LOOP_EXPR_BODY (*expr_p), pre_p);
1086 if (gimplify_ctxp->exit_label)
1088 append_to_statement_list (jump_stmt, pre_p);
1089 *expr_p = build1 (LABEL_EXPR, void_type_node, gimplify_ctxp->exit_label);
1092 *expr_p = jump_stmt;
1094 gimplify_ctxp->exit_label = saved_label;
1099 /* Compare two case labels. Because the front end should already have
1100 made sure that case ranges do not overlap, it is enough to only compare
1101 the CASE_LOW values of each case label. */
1104 compare_case_labels (const void *p1, const void *p2)
1106 tree case1 = *(tree *)p1;
1107 tree case2 = *(tree *)p2;
1109 return tree_int_cst_compare (CASE_LOW (case1), CASE_LOW (case2));
1112 /* Sort the case labels in LABEL_VEC in place in ascending order. */
1115 sort_case_labels (tree label_vec)
1117 size_t len = TREE_VEC_LENGTH (label_vec);
1118 tree default_case = TREE_VEC_ELT (label_vec, len - 1);
1120 if (CASE_LOW (default_case))
1124 /* The last label in the vector should be the default case
1126 for (i = 0; i < len; ++i)
1128 tree t = TREE_VEC_ELT (label_vec, i);
1132 TREE_VEC_ELT (label_vec, i) = TREE_VEC_ELT (label_vec, len - 1);
1133 TREE_VEC_ELT (label_vec, len - 1) = default_case;
1139 qsort (&TREE_VEC_ELT (label_vec, 0), len - 1, sizeof (tree),
1140 compare_case_labels);
1143 /* Gimplify a SWITCH_EXPR, and collect a TREE_VEC of the labels it can
1146 static enum gimplify_status
1147 gimplify_switch_expr (tree *expr_p, tree *pre_p)
1149 tree switch_expr = *expr_p;
1150 enum gimplify_status ret;
1152 ret = gimplify_expr (&SWITCH_COND (switch_expr), pre_p, NULL,
1153 is_gimple_val, fb_rvalue);
1155 if (SWITCH_BODY (switch_expr))
1157 VEC(tree,heap) *labels, *saved_labels;
1158 tree label_vec, default_case = NULL_TREE;
1161 /* If someone can be bothered to fill in the labels, they can
1162 be bothered to null out the body too. */
1163 gcc_assert (!SWITCH_LABELS (switch_expr));
1165 saved_labels = gimplify_ctxp->case_labels;
1166 gimplify_ctxp->case_labels = VEC_alloc (tree, heap, 8);
1168 gimplify_to_stmt_list (&SWITCH_BODY (switch_expr));
1170 labels = gimplify_ctxp->case_labels;
1171 gimplify_ctxp->case_labels = saved_labels;
1173 len = VEC_length (tree, labels);
1175 for (i = 0; i < len; ++i)
1177 tree t = VEC_index (tree, labels, i);
1180 /* The default case must be the last label in the list. */
1182 VEC_replace (tree, labels, i, VEC_index (tree, labels, len - 1));
1188 label_vec = make_tree_vec (len + 1);
1189 SWITCH_LABELS (*expr_p) = label_vec;
1190 append_to_statement_list (switch_expr, pre_p);
1194 /* If the switch has no default label, add one, so that we jump
1195 around the switch body. */
1196 default_case = build (CASE_LABEL_EXPR, void_type_node, NULL_TREE,
1197 NULL_TREE, create_artificial_label ());
1198 append_to_statement_list (SWITCH_BODY (switch_expr), pre_p);
1199 *expr_p = build (LABEL_EXPR, void_type_node,
1200 CASE_LABEL (default_case));
1203 *expr_p = SWITCH_BODY (switch_expr);
1205 for (i = 0; i < len; ++i)
1206 TREE_VEC_ELT (label_vec, i) = VEC_index (tree, labels, i);
1207 TREE_VEC_ELT (label_vec, len) = default_case;
1209 VEC_free (tree, heap, labels);
1211 sort_case_labels (label_vec);
1213 SWITCH_BODY (switch_expr) = NULL;
1216 gcc_assert (SWITCH_LABELS (switch_expr));
1221 static enum gimplify_status
1222 gimplify_case_label_expr (tree *expr_p)
1224 tree expr = *expr_p;
1226 gcc_assert (gimplify_ctxp->case_labels);
1227 VEC_safe_push (tree, heap, gimplify_ctxp->case_labels, expr);
1228 *expr_p = build (LABEL_EXPR, void_type_node, CASE_LABEL (expr));
1232 /* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
1236 build_and_jump (tree *label_p)
1238 if (label_p == NULL)
1239 /* If there's nowhere to jump, just fall through. */
1242 if (*label_p == NULL_TREE)
1244 tree label = create_artificial_label ();
1248 return build1 (GOTO_EXPR, void_type_node, *label_p);
1251 /* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
1252 This also involves building a label to jump to and communicating it to
1253 gimplify_loop_expr through gimplify_ctxp->exit_label. */
1255 static enum gimplify_status
1256 gimplify_exit_expr (tree *expr_p)
1258 tree cond = TREE_OPERAND (*expr_p, 0);
1261 expr = build_and_jump (&gimplify_ctxp->exit_label);
1262 expr = build (COND_EXPR, void_type_node, cond, expr, NULL_TREE);
1268 /* A helper function to be called via walk_tree. Mark all labels under *TP
1269 as being forced. To be called for DECL_INITIAL of static variables. */
1272 force_labels_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1276 if (TREE_CODE (*tp) == LABEL_DECL)
1277 FORCED_LABEL (*tp) = 1;
1282 /* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is
1283 different from its canonical type, wrap the whole thing inside a
1284 NOP_EXPR and force the type of the COMPONENT_REF to be the canonical
1287 The canonical type of a COMPONENT_REF is the type of the field being
1288 referenced--unless the field is a bit-field which can be read directly
1289 in a smaller mode, in which case the canonical type is the
1290 sign-appropriate type corresponding to that mode. */
1293 canonicalize_component_ref (tree *expr_p)
1295 tree expr = *expr_p;
1298 gcc_assert (TREE_CODE (expr) == COMPONENT_REF);
1300 if (INTEGRAL_TYPE_P (TREE_TYPE (expr)))
1301 type = TREE_TYPE (get_unwidened (expr, NULL_TREE));
1303 type = TREE_TYPE (TREE_OPERAND (expr, 1));
1305 if (TREE_TYPE (expr) != type)
1307 tree old_type = TREE_TYPE (expr);
1309 /* Set the type of the COMPONENT_REF to the underlying type. */
1310 TREE_TYPE (expr) = type;
1312 /* And wrap the whole thing inside a NOP_EXPR. */
1313 expr = build1 (NOP_EXPR, old_type, expr);
1319 /* If a NOP conversion is changing a pointer to array of foo to a pointer
1320 to foo, embed that change in the ADDR_EXPR by converting
1325 where L is the lower bound. For simplicity, only do this for constant
1329 canonicalize_addr_expr (tree *expr_p)
1331 tree expr = *expr_p;
1332 tree ctype = TREE_TYPE (expr);
1333 tree addr_expr = TREE_OPERAND (expr, 0);
1334 tree atype = TREE_TYPE (addr_expr);
1335 tree dctype, datype, ddatype, otype, obj_expr;
1337 /* Both cast and addr_expr types should be pointers. */
1338 if (!POINTER_TYPE_P (ctype) || !POINTER_TYPE_P (atype))
1341 /* The addr_expr type should be a pointer to an array. */
1342 datype = TREE_TYPE (atype);
1343 if (TREE_CODE (datype) != ARRAY_TYPE)
1346 /* Both cast and addr_expr types should address the same object type. */
1347 dctype = TREE_TYPE (ctype);
1348 ddatype = TREE_TYPE (datype);
1349 if (!lang_hooks.types_compatible_p (ddatype, dctype))
1352 /* The addr_expr and the object type should match. */
1353 obj_expr = TREE_OPERAND (addr_expr, 0);
1354 otype = TREE_TYPE (obj_expr);
1355 if (!lang_hooks.types_compatible_p (otype, datype))
1358 /* The lower bound and element sizes must be constant. */
1359 if (!TYPE_SIZE_UNIT (dctype)
1360 || TREE_CODE (TYPE_SIZE_UNIT (dctype)) != INTEGER_CST
1361 || !TYPE_DOMAIN (datype) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype))
1362 || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype))) != INTEGER_CST)
1365 /* All checks succeeded. Build a new node to merge the cast. */
1366 *expr_p = build4 (ARRAY_REF, dctype, obj_expr,
1367 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1368 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1369 size_binop (EXACT_DIV_EXPR, TYPE_SIZE_UNIT (dctype),
1370 size_int (TYPE_ALIGN_UNIT (dctype))));
1371 *expr_p = build1 (ADDR_EXPR, ctype, *expr_p);
1374 /* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
1375 underneath as appropriate. */
1377 static enum gimplify_status
1378 gimplify_conversion (tree *expr_p)
1380 gcc_assert (TREE_CODE (*expr_p) == NOP_EXPR
1381 || TREE_CODE (*expr_p) == CONVERT_EXPR);
1383 /* Then strip away all but the outermost conversion. */
1384 STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0));
1386 /* And remove the outermost conversion if it's useless. */
1387 if (tree_ssa_useless_type_conversion (*expr_p))
1388 *expr_p = TREE_OPERAND (*expr_p, 0);
1390 /* If we still have a conversion at the toplevel,
1391 then canonicalize some constructs. */
1392 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1394 tree sub = TREE_OPERAND (*expr_p, 0);
1396 /* If a NOP conversion is changing the type of a COMPONENT_REF
1397 expression, then canonicalize its type now in order to expose more
1398 redundant conversions. */
1399 if (TREE_CODE (sub) == COMPONENT_REF)
1400 canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0));
1402 /* If a NOP conversion is changing a pointer to array of foo
1403 to a pointer to foo, embed that change in the ADDR_EXPR. */
1404 else if (TREE_CODE (sub) == ADDR_EXPR)
1405 canonicalize_addr_expr (expr_p);
1411 /* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
1412 node pointed by EXPR_P.
1415 : min_lval '[' val ']'
1417 | compound_lval '[' val ']'
1418 | compound_lval '.' ID
1420 This is not part of the original SIMPLE definition, which separates
1421 array and member references, but it seems reasonable to handle them
1422 together. Also, this way we don't run into problems with union
1423 aliasing; gcc requires that for accesses through a union to alias, the
1424 union reference must be explicit, which was not always the case when we
1425 were splitting up array and member refs.
1427 PRE_P points to the list where side effects that must happen before
1428 *EXPR_P should be stored.
1430 POST_P points to the list where side effects that must happen after
1431 *EXPR_P should be stored. */
1433 static enum gimplify_status
1434 gimplify_compound_lval (tree *expr_p, tree *pre_p,
1435 tree *post_p, fallback_t fallback)
1438 VEC(tree,heap) *stack;
1439 enum gimplify_status ret = GS_OK, tret;
1442 /* Create a stack of the subexpressions so later we can walk them in
1443 order from inner to outer. */
1444 stack = VEC_alloc (tree, heap, 10);
1446 /* We can handle anything that get_inner_reference can deal with. */
1447 for (p = expr_p; ; p = &TREE_OPERAND (*p, 0))
1449 /* Fold INDIRECT_REFs now to turn them into ARRAY_REFs. */
1450 if (TREE_CODE (*p) == INDIRECT_REF)
1451 *p = fold_indirect_ref (*p);
1452 if (!handled_component_p (*p))
1454 VEC_safe_push (tree, heap, stack, *p);
1457 gcc_assert (VEC_length (tree, stack));
1459 /* Now STACK is a stack of pointers to all the refs we've walked through
1460 and P points to the innermost expression.
1462 Java requires that we elaborated nodes in source order. That
1463 means we must gimplify the inner expression followed by each of
1464 the indices, in order. But we can't gimplify the inner
1465 expression until we deal with any variable bounds, sizes, or
1466 positions in order to deal with PLACEHOLDER_EXPRs.
1468 So we do this in three steps. First we deal with the annotations
1469 for any variables in the components, then we gimplify the base,
1470 then we gimplify any indices, from left to right. */
1471 for (i = VEC_length (tree, stack) - 1; i >= 0; i--)
1473 tree t = VEC_index (tree, stack, i);
1475 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1477 /* Gimplify the low bound and element type size and put them into
1478 the ARRAY_REF. If these values are set, they have already been
1480 if (!TREE_OPERAND (t, 2))
1482 tree low = unshare_expr (array_ref_low_bound (t));
1483 if (!is_gimple_min_invariant (low))
1485 TREE_OPERAND (t, 2) = low;
1486 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1487 is_gimple_formal_tmp_reg, fb_rvalue);
1488 ret = MIN (ret, tret);
1492 if (!TREE_OPERAND (t, 3))
1494 tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
1495 tree elmt_size = unshare_expr (array_ref_element_size (t));
1496 tree factor = size_int (TYPE_ALIGN_UNIT (elmt_type));
1498 /* Divide the element size by the alignment of the element
1500 elmt_size = size_binop (EXACT_DIV_EXPR, elmt_size, factor);
1502 if (!is_gimple_min_invariant (elmt_size))
1504 TREE_OPERAND (t, 3) = elmt_size;
1505 tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p,
1506 is_gimple_formal_tmp_reg, fb_rvalue);
1507 ret = MIN (ret, tret);
1511 else if (TREE_CODE (t) == COMPONENT_REF)
1513 /* Set the field offset into T and gimplify it. */
1514 if (!TREE_OPERAND (t, 2))
1516 tree offset = unshare_expr (component_ref_field_offset (t));
1517 tree field = TREE_OPERAND (t, 1);
1519 = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
1521 /* Divide the offset by its alignment. */
1522 offset = size_binop (EXACT_DIV_EXPR, offset, factor);
1524 if (!is_gimple_min_invariant (offset))
1526 TREE_OPERAND (t, 2) = offset;
1527 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1528 is_gimple_formal_tmp_reg, fb_rvalue);
1529 ret = MIN (ret, tret);
1535 /* Step 2 is to gimplify the base expression. */
1536 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1537 ret = MIN (ret, tret);
1539 /* And finally, the indices and operands to BIT_FIELD_REF. During this
1540 loop we also remove any useless conversions. */
1541 for (; VEC_length (tree, stack) > 0; )
1543 tree t = VEC_pop (tree, stack);
1545 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1547 /* Gimplify the dimension.
1548 Temporary fix for gcc.c-torture/execute/20040313-1.c.
1549 Gimplify non-constant array indices into a temporary
1551 FIXME - The real fix is to gimplify post-modify
1552 expressions into a minimal gimple lvalue. However, that
1553 exposes bugs in alias analysis. The alias analyzer does
1554 not handle &PTR->FIELD very well. Will fix after the
1555 branch is merged into mainline (dnovillo 2004-05-03). */
1556 if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
1558 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1559 is_gimple_formal_tmp_reg, fb_rvalue);
1560 ret = MIN (ret, tret);
1563 else if (TREE_CODE (t) == BIT_FIELD_REF)
1565 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1566 is_gimple_val, fb_rvalue);
1567 ret = MIN (ret, tret);
1568 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1569 is_gimple_val, fb_rvalue);
1570 ret = MIN (ret, tret);
1573 STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0));
1575 /* The innermost expression P may have originally had TREE_SIDE_EFFECTS
1576 set which would have caused all the outer expressions in EXPR_P
1577 leading to P to also have had TREE_SIDE_EFFECTS set. */
1578 recalculate_side_effects (t);
1581 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1582 ret = MIN (ret, tret);
1584 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
1585 if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF)
1587 canonicalize_component_ref (expr_p);
1588 ret = MIN (ret, GS_OK);
1591 VEC_free (tree, heap, stack);
1596 /* Gimplify the self modifying expression pointed by EXPR_P (++, --, +=, -=).
1598 PRE_P points to the list where side effects that must happen before
1599 *EXPR_P should be stored.
1601 POST_P points to the list where side effects that must happen after
1602 *EXPR_P should be stored.
1604 WANT_VALUE is nonzero iff we want to use the value of this expression
1605 in another expression. */
1607 static enum gimplify_status
1608 gimplify_self_mod_expr (tree *expr_p, tree *pre_p, tree *post_p,
1611 enum tree_code code;
1612 tree lhs, lvalue, rhs, t1;
1614 enum tree_code arith_code;
1615 enum gimplify_status ret;
1617 code = TREE_CODE (*expr_p);
1619 gcc_assert (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR
1620 || code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR);
1622 /* Prefix or postfix? */
1623 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
1624 /* Faster to treat as prefix if result is not used. */
1625 postfix = want_value;
1629 /* Add or subtract? */
1630 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
1631 arith_code = PLUS_EXPR;
1633 arith_code = MINUS_EXPR;
1635 /* Gimplify the LHS into a GIMPLE lvalue. */
1636 lvalue = TREE_OPERAND (*expr_p, 0);
1637 ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
1638 if (ret == GS_ERROR)
1641 /* Extract the operands to the arithmetic operation. */
1643 rhs = TREE_OPERAND (*expr_p, 1);
1645 /* For postfix operator, we evaluate the LHS to an rvalue and then use
1646 that as the result value and in the postqueue operation. */
1649 ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
1650 if (ret == GS_ERROR)
1654 t1 = build (arith_code, TREE_TYPE (*expr_p), lhs, rhs);
1655 t1 = build (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
1659 gimplify_and_add (t1, post_p);
1670 /* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
1673 maybe_with_size_expr (tree *expr_p)
1675 tree expr = *expr_p;
1676 tree type = TREE_TYPE (expr);
1679 /* If we've already wrapped this or the type is error_mark_node, we can't do
1681 if (TREE_CODE (expr) == WITH_SIZE_EXPR
1682 || type == error_mark_node)
1685 /* If the size isn't known or is a constant, we have nothing to do. */
1686 size = TYPE_SIZE_UNIT (type);
1687 if (!size || TREE_CODE (size) == INTEGER_CST)
1690 /* Otherwise, make a WITH_SIZE_EXPR. */
1691 size = unshare_expr (size);
1692 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr);
1693 *expr_p = build2 (WITH_SIZE_EXPR, type, expr, size);
1696 /* Subroutine of gimplify_call_expr: Gimplify a single argument. */
1698 static enum gimplify_status
1699 gimplify_arg (tree *expr_p, tree *pre_p)
1701 bool (*test) (tree);
1704 /* In general, we allow lvalues for function arguments to avoid
1705 extra overhead of copying large aggregates out of even larger
1706 aggregates into temporaries only to copy the temporaries to
1707 the argument list. Make optimizers happy by pulling out to
1708 temporaries those types that fit in registers. */
1709 if (is_gimple_reg_type (TREE_TYPE (*expr_p)))
1710 test = is_gimple_val, fb = fb_rvalue;
1712 test = is_gimple_lvalue, fb = fb_either;
1714 /* If this is a variable sized type, we must remember the size. */
1715 maybe_with_size_expr (expr_p);
1717 /* There is a sequence point before a function call. Side effects in
1718 the argument list must occur before the actual call. So, when
1719 gimplifying arguments, force gimplify_expr to use an internal
1720 post queue which is then appended to the end of PRE_P. */
1721 return gimplify_expr (expr_p, pre_p, NULL, test, fb);
1724 /* Gimplify the CALL_EXPR node pointed by EXPR_P. PRE_P points to the
1725 list where side effects that must happen before *EXPR_P should be stored.
1726 WANT_VALUE is true if the result of the call is desired. */
1728 static enum gimplify_status
1729 gimplify_call_expr (tree *expr_p, tree *pre_p, bool want_value)
1733 enum gimplify_status ret;
1735 gcc_assert (TREE_CODE (*expr_p) == CALL_EXPR);
1737 /* For reliable diagnostics during inlining, it is necessary that
1738 every call_expr be annotated with file and line. */
1739 if (! EXPR_HAS_LOCATION (*expr_p))
1740 SET_EXPR_LOCATION (*expr_p, input_location);
1742 /* This may be a call to a builtin function.
1744 Builtin function calls may be transformed into different
1745 (and more efficient) builtin function calls under certain
1746 circumstances. Unfortunately, gimplification can muck things
1747 up enough that the builtin expanders are not aware that certain
1748 transformations are still valid.
1750 So we attempt transformation/gimplification of the call before
1751 we gimplify the CALL_EXPR. At this time we do not manage to
1752 transform all calls in the same manner as the expanders do, but
1753 we do transform most of them. */
1754 decl = get_callee_fndecl (*expr_p);
1755 if (decl && DECL_BUILT_IN (decl))
1757 tree fndecl = get_callee_fndecl (*expr_p);
1758 tree arglist = TREE_OPERAND (*expr_p, 1);
1759 tree new = fold_builtin (fndecl, arglist, !want_value);
1761 if (new && new != *expr_p)
1763 /* There was a transformation of this call which computes the
1764 same value, but in a more efficient way. Return and try
1770 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
1771 && DECL_FUNCTION_CODE (decl) == BUILT_IN_VA_START)
1773 if (!arglist || !TREE_CHAIN (arglist))
1775 error ("too few arguments to function %<va_start%>");
1776 *expr_p = build_empty_stmt ();
1780 if (fold_builtin_next_arg (TREE_CHAIN (arglist)))
1782 *expr_p = build_empty_stmt ();
1785 /* Avoid gimplifying the second argument to va_start, which needs
1786 to be the plain PARM_DECL. */
1787 return gimplify_arg (&TREE_VALUE (TREE_OPERAND (*expr_p, 1)), pre_p);
1791 /* There is a sequence point before the call, so any side effects in
1792 the calling expression must occur before the actual call. Force
1793 gimplify_expr to use an internal post queue. */
1794 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, NULL,
1795 is_gimple_call_addr, fb_rvalue);
1797 if (PUSH_ARGS_REVERSED)
1798 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1799 for (arglist = TREE_OPERAND (*expr_p, 1); arglist;
1800 arglist = TREE_CHAIN (arglist))
1802 enum gimplify_status t;
1804 t = gimplify_arg (&TREE_VALUE (arglist), pre_p);
1809 if (PUSH_ARGS_REVERSED)
1810 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
1812 /* Try this again in case gimplification exposed something. */
1813 if (ret != GS_ERROR && decl && DECL_BUILT_IN (decl))
1815 tree fndecl = get_callee_fndecl (*expr_p);
1816 tree arglist = TREE_OPERAND (*expr_p, 1);
1817 tree new = fold_builtin (fndecl, arglist, !want_value);
1819 if (new && new != *expr_p)
1821 /* There was a transformation of this call which computes the
1822 same value, but in a more efficient way. Return and try
1829 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
1830 decl. This allows us to eliminate redundant or useless
1831 calls to "const" functions. */
1832 if (TREE_CODE (*expr_p) == CALL_EXPR
1833 && (call_expr_flags (*expr_p) & (ECF_CONST | ECF_PURE)))
1834 TREE_SIDE_EFFECTS (*expr_p) = 0;
1839 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
1840 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
1842 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
1843 condition is true or false, respectively. If null, we should generate
1844 our own to skip over the evaluation of this specific expression.
1846 This function is the tree equivalent of do_jump.
1848 shortcut_cond_r should only be called by shortcut_cond_expr. */
1851 shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p)
1853 tree local_label = NULL_TREE;
1854 tree t, expr = NULL;
1856 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
1857 retain the shortcut semantics. Just insert the gotos here;
1858 shortcut_cond_expr will append the real blocks later. */
1859 if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
1861 /* Turn if (a && b) into
1863 if (a); else goto no;
1864 if (b) goto yes; else goto no;
1867 if (false_label_p == NULL)
1868 false_label_p = &local_label;
1870 t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p);
1871 append_to_statement_list (t, &expr);
1873 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1875 append_to_statement_list (t, &expr);
1877 else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
1879 /* Turn if (a || b) into
1882 if (b) goto yes; else goto no;
1885 if (true_label_p == NULL)
1886 true_label_p = &local_label;
1888 t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL);
1889 append_to_statement_list (t, &expr);
1891 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1893 append_to_statement_list (t, &expr);
1895 else if (TREE_CODE (pred) == COND_EXPR)
1897 /* As long as we're messing with gotos, turn if (a ? b : c) into
1899 if (b) goto yes; else goto no;
1901 if (c) goto yes; else goto no; */
1902 expr = build (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
1903 shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
1905 shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
1910 expr = build (COND_EXPR, void_type_node, pred,
1911 build_and_jump (true_label_p),
1912 build_and_jump (false_label_p));
1917 t = build1 (LABEL_EXPR, void_type_node, local_label);
1918 append_to_statement_list (t, &expr);
1925 shortcut_cond_expr (tree expr)
1927 tree pred = TREE_OPERAND (expr, 0);
1928 tree then_ = TREE_OPERAND (expr, 1);
1929 tree else_ = TREE_OPERAND (expr, 2);
1930 tree true_label, false_label, end_label, t;
1932 tree *false_label_p;
1933 bool emit_end, emit_false, jump_over_else;
1934 bool then_se = then_ && TREE_SIDE_EFFECTS (then_);
1935 bool else_se = else_ && TREE_SIDE_EFFECTS (else_);
1937 /* First do simple transformations. */
1940 /* If there is no 'else', turn (a && b) into if (a) if (b). */
1941 while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
1943 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
1944 then_ = shortcut_cond_expr (expr);
1945 then_se = then_ && TREE_SIDE_EFFECTS (then_);
1946 pred = TREE_OPERAND (pred, 0);
1947 expr = build (COND_EXPR, void_type_node, pred, then_, NULL_TREE);
1952 /* If there is no 'then', turn
1955 if (a); else if (b); else d. */
1956 while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
1958 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
1959 else_ = shortcut_cond_expr (expr);
1960 else_se = else_ && TREE_SIDE_EFFECTS (else_);
1961 pred = TREE_OPERAND (pred, 0);
1962 expr = build (COND_EXPR, void_type_node, pred, NULL_TREE, else_);
1966 /* If we're done, great. */
1967 if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
1968 && TREE_CODE (pred) != TRUTH_ORIF_EXPR)
1971 /* Otherwise we need to mess with gotos. Change
1974 if (a); else goto no;
1977 and recursively gimplify the condition. */
1979 true_label = false_label = end_label = NULL_TREE;
1981 /* If our arms just jump somewhere, hijack those labels so we don't
1982 generate jumps to jumps. */
1985 && TREE_CODE (then_) == GOTO_EXPR
1986 && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
1988 true_label = GOTO_DESTINATION (then_);
1994 && TREE_CODE (else_) == GOTO_EXPR
1995 && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
1997 false_label = GOTO_DESTINATION (else_);
2002 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2004 true_label_p = &true_label;
2006 true_label_p = NULL;
2008 /* The 'else' branch also needs a label if it contains interesting code. */
2009 if (false_label || else_se)
2010 false_label_p = &false_label;
2012 false_label_p = NULL;
2014 /* If there was nothing else in our arms, just forward the label(s). */
2015 if (!then_se && !else_se)
2016 return shortcut_cond_r (pred, true_label_p, false_label_p);
2018 /* If our last subexpression already has a terminal label, reuse it. */
2020 expr = expr_last (else_);
2022 expr = expr_last (then_);
2025 if (expr && TREE_CODE (expr) == LABEL_EXPR)
2026 end_label = LABEL_EXPR_LABEL (expr);
2028 /* If we don't care about jumping to the 'else' branch, jump to the end
2029 if the condition is false. */
2031 false_label_p = &end_label;
2033 /* We only want to emit these labels if we aren't hijacking them. */
2034 emit_end = (end_label == NULL_TREE);
2035 emit_false = (false_label == NULL_TREE);
2037 /* We only emit the jump over the else clause if we have to--if the
2038 then clause may fall through. Otherwise we can wind up with a
2039 useless jump and a useless label at the end of gimplified code,
2040 which will cause us to think that this conditional as a whole
2041 falls through even if it doesn't. If we then inline a function
2042 which ends with such a condition, that can cause us to issue an
2043 inappropriate warning about control reaching the end of a
2044 non-void function. */
2045 jump_over_else = block_may_fallthru (then_);
2047 pred = shortcut_cond_r (pred, true_label_p, false_label_p);
2050 append_to_statement_list (pred, &expr);
2052 append_to_statement_list (then_, &expr);
2057 t = build_and_jump (&end_label);
2058 append_to_statement_list (t, &expr);
2062 t = build1 (LABEL_EXPR, void_type_node, false_label);
2063 append_to_statement_list (t, &expr);
2065 append_to_statement_list (else_, &expr);
2067 if (emit_end && end_label)
2069 t = build1 (LABEL_EXPR, void_type_node, end_label);
2070 append_to_statement_list (t, &expr);
2076 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2079 gimple_boolify (tree expr)
2081 tree type = TREE_TYPE (expr);
2083 if (TREE_CODE (type) == BOOLEAN_TYPE)
2086 switch (TREE_CODE (expr))
2088 case TRUTH_AND_EXPR:
2090 case TRUTH_XOR_EXPR:
2091 case TRUTH_ANDIF_EXPR:
2092 case TRUTH_ORIF_EXPR:
2093 /* Also boolify the arguments of truth exprs. */
2094 TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
2097 case TRUTH_NOT_EXPR:
2098 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2101 case EQ_EXPR: case NE_EXPR:
2102 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2103 /* These expressions always produce boolean results. */
2104 TREE_TYPE (expr) = boolean_type_node;
2108 /* Other expressions that get here must have boolean values, but
2109 might need to be converted to the appropriate mode. */
2110 return convert (boolean_type_node, expr);
2114 /* Convert the conditional expression pointed by EXPR_P '(p) ? a : b;'
2123 The second form is used when *EXPR_P is of type void.
2125 TARGET is the tree for T1 above.
2127 PRE_P points to the list where side effects that must happen before
2128 *EXPR_P should be stored.
2130 POST_P points to the list where side effects that must happen after
2131 *EXPR_P should be stored. */
2133 static enum gimplify_status
2134 gimplify_cond_expr (tree *expr_p, tree *pre_p, tree *post_p, tree target,
2135 fallback_t fallback)
2137 tree expr = *expr_p;
2138 tree tmp, tmp2, type;
2139 enum gimplify_status ret;
2141 type = TREE_TYPE (expr);
2143 /* If this COND_EXPR has a value, copy the values into a temporary within
2145 if (! VOID_TYPE_P (type))
2151 ret = gimplify_expr (&target, pre_p, post_p,
2152 is_gimple_min_lval, fb_lvalue);
2153 if (ret != GS_ERROR)
2155 result = tmp = target;
2156 tmp2 = unshare_expr (target);
2158 else if ((fallback & fb_lvalue) == 0)
2160 result = tmp2 = tmp = create_tmp_var (TREE_TYPE (expr), "iftmp");
2165 tree type = build_pointer_type (TREE_TYPE (expr));
2167 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2168 TREE_OPERAND (expr, 1) =
2169 build_fold_addr_expr (TREE_OPERAND (expr, 1));
2171 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2172 TREE_OPERAND (expr, 2) =
2173 build_fold_addr_expr (TREE_OPERAND (expr, 2));
2175 tmp2 = tmp = create_tmp_var (type, "iftmp");
2177 expr = build (COND_EXPR, void_type_node, TREE_OPERAND (expr, 0),
2178 TREE_OPERAND (expr, 1), TREE_OPERAND (expr, 2));
2180 result = build_fold_indirect_ref (tmp);
2184 /* Build the then clause, 't1 = a;'. But don't build an assignment
2185 if this branch is void; in C++ it can be, if it's a throw. */
2186 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2187 TREE_OPERAND (expr, 1)
2188 = build (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 1));
2190 /* Build the else clause, 't1 = b;'. */
2191 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2192 TREE_OPERAND (expr, 2)
2193 = build (MODIFY_EXPR, void_type_node, tmp2, TREE_OPERAND (expr, 2));
2195 TREE_TYPE (expr) = void_type_node;
2196 recalculate_side_effects (expr);
2198 /* Move the COND_EXPR to the prequeue. */
2199 gimplify_and_add (expr, pre_p);
2205 /* Make sure the condition has BOOLEAN_TYPE. */
2206 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2208 /* Break apart && and || conditions. */
2209 if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
2210 || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
2212 expr = shortcut_cond_expr (expr);
2214 if (expr != *expr_p)
2218 /* We can't rely on gimplify_expr to re-gimplify the expanded
2219 form properly, as cleanups might cause the target labels to be
2220 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2221 set up a conditional context. */
2222 gimple_push_condition ();
2223 gimplify_stmt (expr_p);
2224 gimple_pop_condition (pre_p);
2230 /* Now do the normal gimplification. */
2231 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2232 is_gimple_condexpr, fb_rvalue);
2234 gimple_push_condition ();
2236 gimplify_to_stmt_list (&TREE_OPERAND (expr, 1));
2237 gimplify_to_stmt_list (&TREE_OPERAND (expr, 2));
2238 recalculate_side_effects (expr);
2240 gimple_pop_condition (pre_p);
2242 if (ret == GS_ERROR)
2244 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2246 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 2)))
2247 /* Rewrite "if (a); else b" to "if (!a) b" */
2249 TREE_OPERAND (expr, 0) = invert_truthvalue (TREE_OPERAND (expr, 0));
2250 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2251 is_gimple_condexpr, fb_rvalue);
2253 tmp = TREE_OPERAND (expr, 1);
2254 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 2);
2255 TREE_OPERAND (expr, 2) = tmp;
2258 /* Both arms are empty; replace the COND_EXPR with its predicate. */
2259 expr = TREE_OPERAND (expr, 0);
2265 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2266 a call to __builtin_memcpy. */
2268 static enum gimplify_status
2269 gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value)
2271 tree args, t, to, to_ptr, from;
2273 to = TREE_OPERAND (*expr_p, 0);
2274 from = TREE_OPERAND (*expr_p, 1);
2276 args = tree_cons (NULL, size, NULL);
2278 t = build_fold_addr_expr (from);
2279 args = tree_cons (NULL, t, args);
2281 to_ptr = build_fold_addr_expr (to);
2282 args = tree_cons (NULL, to_ptr, args);
2283 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
2284 t = build_function_call_expr (t, args);
2288 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2289 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2296 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2297 a call to __builtin_memset. In this case we know that the RHS is
2298 a CONSTRUCTOR with an empty element list. */
2300 static enum gimplify_status
2301 gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value)
2303 tree args, t, to, to_ptr;
2305 to = TREE_OPERAND (*expr_p, 0);
2307 args = tree_cons (NULL, size, NULL);
2309 args = tree_cons (NULL, integer_zero_node, args);
2311 to_ptr = build_fold_addr_expr (to);
2312 args = tree_cons (NULL, to_ptr, args);
2313 t = implicit_built_in_decls[BUILT_IN_MEMSET];
2314 t = build_function_call_expr (t, args);
2318 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2319 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2326 /* A subroutine of gimplify_init_ctor_preeval. Called via walk_tree,
2327 determine, cautiously, if a CONSTRUCTOR overlaps the lhs of an
2328 assignment. Returns non-null if we detect a potential overlap. */
2330 struct gimplify_init_ctor_preeval_data
2332 /* The base decl of the lhs object. May be NULL, in which case we
2333 have to assume the lhs is indirect. */
2336 /* The alias set of the lhs object. */
2341 gimplify_init_ctor_preeval_1 (tree *tp, int *walk_subtrees, void *xdata)
2343 struct gimplify_init_ctor_preeval_data *data
2344 = (struct gimplify_init_ctor_preeval_data *) xdata;
2347 /* If we find the base object, obviously we have overlap. */
2348 if (data->lhs_base_decl == t)
2351 /* If the constructor component is indirect, determine if we have a
2352 potential overlap with the lhs. The only bits of information we
2353 have to go on at this point are addressability and alias sets. */
2354 if (TREE_CODE (t) == INDIRECT_REF
2355 && (!data->lhs_base_decl || TREE_ADDRESSABLE (data->lhs_base_decl))
2356 && alias_sets_conflict_p (data->lhs_alias_set, get_alias_set (t)))
2359 if (IS_TYPE_OR_DECL_P (t))
2364 /* A subroutine of gimplify_init_constructor. Pre-evaluate *EXPR_P,
2365 force values that overlap with the lhs (as described by *DATA)
2366 into temporaries. */
2369 gimplify_init_ctor_preeval (tree *expr_p, tree *pre_p, tree *post_p,
2370 struct gimplify_init_ctor_preeval_data *data)
2372 enum gimplify_status one;
2374 /* If the value is invariant, then there's nothing to pre-evaluate.
2375 But ensure it doesn't have any side-effects since a SAVE_EXPR is
2376 invariant but has side effects and might contain a reference to
2377 the object we're initializing. */
2378 if (TREE_INVARIANT (*expr_p) && !TREE_SIDE_EFFECTS (*expr_p))
2381 /* If the type has non-trivial constructors, we can't pre-evaluate. */
2382 if (TREE_ADDRESSABLE (TREE_TYPE (*expr_p)))
2385 /* Recurse for nested constructors. */
2386 if (TREE_CODE (*expr_p) == CONSTRUCTOR)
2389 for (list = CONSTRUCTOR_ELTS (*expr_p); list ; list = TREE_CHAIN (list))
2390 gimplify_init_ctor_preeval (&TREE_VALUE (list), pre_p, post_p, data);
2394 /* We can't preevaluate if the type contains a placeholder. */
2395 if (type_contains_placeholder_p (TREE_TYPE (*expr_p)))
2398 /* Gimplify the constructor element to something appropriate for the rhs
2399 of a MODIFY_EXPR. Given that we know the lhs is an aggregate, we know
2400 the gimplifier will consider this a store to memory. Doing this
2401 gimplification now means that we won't have to deal with complicated
2402 language-specific trees, nor trees like SAVE_EXPR that can induce
2403 exponential search behavior. */
2404 one = gimplify_expr (expr_p, pre_p, post_p, is_gimple_mem_rhs, fb_rvalue);
2405 if (one == GS_ERROR)
2411 /* If we gimplified to a bare decl, we can be sure that it doesn't overlap
2412 with the lhs, since "a = { .x=a }" doesn't make sense. This will
2413 always be true for all scalars, since is_gimple_mem_rhs insists on a
2414 temporary variable for them. */
2415 if (DECL_P (*expr_p))
2418 /* If this is of variable size, we have no choice but to assume it doesn't
2419 overlap since we can't make a temporary for it. */
2420 if (!TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (*expr_p))))
2423 /* Otherwise, we must search for overlap ... */
2424 if (!walk_tree (expr_p, gimplify_init_ctor_preeval_1, data, NULL))
2427 /* ... and if found, force the value into a temporary. */
2428 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
2431 /* A subroutine of gimplify_init_ctor_eval. Create a loop for
2432 a RANGE_EXPR in a CONSTRUCTOR for an array.
2436 object[var] = value;
2443 We increment var _after_ the loop exit check because we might otherwise
2444 fail if upper == TYPE_MAX_VALUE (type for upper).
2446 Note that we never have to deal with SAVE_EXPRs here, because this has
2447 already been taken care of for us, in gimplify_init_ctor_preeval(). */
2449 static void gimplify_init_ctor_eval (tree, tree, tree *, bool);
2452 gimplify_init_ctor_eval_range (tree object, tree lower, tree upper,
2453 tree value, tree array_elt_type,
2454 tree *pre_p, bool cleared)
2456 tree loop_entry_label, loop_exit_label;
2457 tree var, var_type, cref;
2459 loop_entry_label = create_artificial_label ();
2460 loop_exit_label = create_artificial_label ();
2462 /* Create and initialize the index variable. */
2463 var_type = TREE_TYPE (upper);
2464 var = create_tmp_var (var_type, NULL);
2465 append_to_statement_list (build2 (MODIFY_EXPR, var_type, var, lower), pre_p);
2467 /* Add the loop entry label. */
2468 append_to_statement_list (build1 (LABEL_EXPR,
2473 /* Build the reference. */
2474 cref = build4 (ARRAY_REF, array_elt_type, unshare_expr (object),
2475 var, NULL_TREE, NULL_TREE);
2477 /* If we are a constructor, just call gimplify_init_ctor_eval to do
2478 the store. Otherwise just assign value to the reference. */
2480 if (TREE_CODE (value) == CONSTRUCTOR)
2481 /* NB we might have to call ourself recursively through
2482 gimplify_init_ctor_eval if the value is a constructor. */
2483 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
2486 append_to_statement_list (build2 (MODIFY_EXPR, TREE_TYPE (cref),
2490 /* We exit the loop when the index var is equal to the upper bound. */
2491 gimplify_and_add (build3 (COND_EXPR, void_type_node,
2492 build2 (EQ_EXPR, boolean_type_node,
2500 /* Otherwise, increment the index var... */
2501 append_to_statement_list (build2 (MODIFY_EXPR, var_type, var,
2502 build2 (PLUS_EXPR, var_type, var,
2503 fold_convert (var_type,
2504 integer_one_node))),
2507 /* ...and jump back to the loop entry. */
2508 append_to_statement_list (build1 (GOTO_EXPR,
2513 /* Add the loop exit label. */
2514 append_to_statement_list (build1 (LABEL_EXPR,
2520 /* Return true if FDECL is accessing a field that is zero sized. */
2523 zero_sized_field_decl (tree fdecl)
2525 if (TREE_CODE (fdecl) == FIELD_DECL && DECL_SIZE (fdecl)
2526 && integer_zerop (DECL_SIZE (fdecl)))
2531 /* A subroutine of gimplify_init_constructor. Generate individual
2532 MODIFY_EXPRs for a CONSTRUCTOR. OBJECT is the LHS against which the
2533 assignments should happen. LIST is the CONSTRUCTOR_ELTS of the
2534 CONSTRUCTOR. CLEARED is true if the entire LHS object has been
2538 gimplify_init_ctor_eval (tree object, tree list, tree *pre_p, bool cleared)
2540 tree array_elt_type = NULL;
2542 if (TREE_CODE (TREE_TYPE (object)) == ARRAY_TYPE)
2543 array_elt_type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object)));
2545 for (; list; list = TREE_CHAIN (list))
2547 tree purpose, value, cref, init;
2549 purpose = TREE_PURPOSE (list);
2550 value = TREE_VALUE (list);
2552 /* NULL values are created above for gimplification errors. */
2556 if (cleared && initializer_zerop (value))
2559 /* ??? Here's to hoping the front end fills in all of the indices,
2560 so we don't have to figure out what's missing ourselves. */
2561 gcc_assert (purpose);
2563 if (zero_sized_field_decl (purpose))
2566 /* If we have a RANGE_EXPR, we have to build a loop to assign the
2568 if (TREE_CODE (purpose) == RANGE_EXPR)
2570 tree lower = TREE_OPERAND (purpose, 0);
2571 tree upper = TREE_OPERAND (purpose, 1);
2573 /* If the lower bound is equal to upper, just treat it as if
2574 upper was the index. */
2575 if (simple_cst_equal (lower, upper))
2579 gimplify_init_ctor_eval_range (object, lower, upper, value,
2580 array_elt_type, pre_p, cleared);
2587 cref = build (ARRAY_REF, array_elt_type, unshare_expr (object),
2588 purpose, NULL_TREE, NULL_TREE);
2591 cref = build (COMPONENT_REF, TREE_TYPE (purpose),
2592 unshare_expr (object), purpose, NULL_TREE);
2594 if (TREE_CODE (value) == CONSTRUCTOR)
2595 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
2599 init = build (MODIFY_EXPR, TREE_TYPE (cref), cref, value);
2600 gimplify_and_add (init, pre_p);
2605 /* A subroutine of gimplify_modify_expr. Break out elements of a
2606 CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.
2608 Note that we still need to clear any elements that don't have explicit
2609 initializers, so if not all elements are initialized we keep the
2610 original MODIFY_EXPR, we just remove all of the constructor elements. */
2612 static enum gimplify_status
2613 gimplify_init_constructor (tree *expr_p, tree *pre_p,
2614 tree *post_p, bool want_value)
2617 tree ctor = TREE_OPERAND (*expr_p, 1);
2618 tree type = TREE_TYPE (ctor);
2619 enum gimplify_status ret;
2622 if (TREE_CODE (ctor) != CONSTRUCTOR)
2623 return GS_UNHANDLED;
2625 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
2626 is_gimple_lvalue, fb_lvalue);
2627 if (ret == GS_ERROR)
2629 object = TREE_OPERAND (*expr_p, 0);
2631 elt_list = CONSTRUCTOR_ELTS (ctor);
2634 switch (TREE_CODE (type))
2638 case QUAL_UNION_TYPE:
2641 struct gimplify_init_ctor_preeval_data preeval_data;
2642 HOST_WIDE_INT num_type_elements, num_ctor_elements;
2643 HOST_WIDE_INT num_nonzero_elements, num_nonconstant_elements;
2646 /* Aggregate types must lower constructors to initialization of
2647 individual elements. The exception is that a CONSTRUCTOR node
2648 with no elements indicates zero-initialization of the whole. */
2649 if (elt_list == NULL)
2652 categorize_ctor_elements (ctor, &num_nonzero_elements,
2653 &num_nonconstant_elements,
2654 &num_ctor_elements, &cleared);
2656 /* If a const aggregate variable is being initialized, then it
2657 should never be a lose to promote the variable to be static. */
2658 if (num_nonconstant_elements == 0
2659 && num_nonzero_elements > 1
2660 && TREE_READONLY (object)
2661 && TREE_CODE (object) == VAR_DECL)
2663 DECL_INITIAL (object) = ctor;
2664 TREE_STATIC (object) = 1;
2665 if (!DECL_NAME (object))
2666 DECL_NAME (object) = create_tmp_var_name ("C");
2667 walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL);
2669 /* ??? C++ doesn't automatically append a .<number> to the
2670 assembler name, and even when it does, it looks a FE private
2671 data structures to figure out what that number should be,
2672 which are not set for this variable. I suppose this is
2673 important for local statics for inline functions, which aren't
2674 "local" in the object file sense. So in order to get a unique
2675 TU-local symbol, we must invoke the lhd version now. */
2676 lhd_set_decl_assembler_name (object);
2678 *expr_p = NULL_TREE;
2682 /* If there are "lots" of initialized elements, even discounting
2683 those that are not address constants (and thus *must* be
2684 computed at runtime), then partition the constructor into
2685 constant and non-constant parts. Block copy the constant
2686 parts in, then generate code for the non-constant parts. */
2687 /* TODO. There's code in cp/typeck.c to do this. */
2689 num_type_elements = count_type_elements (TREE_TYPE (ctor));
2691 /* If there are "lots" of zeros, then block clear the object first. */
2692 if (num_type_elements - num_nonzero_elements > CLEAR_RATIO
2693 && num_nonzero_elements < num_type_elements/4)
2696 /* ??? This bit ought not be needed. For any element not present
2697 in the initializer, we should simply set them to zero. Except
2698 we'd need to *find* the elements that are not present, and that
2699 requires trickery to avoid quadratic compile-time behavior in
2700 large cases or excessive memory use in small cases. */
2701 else if (num_ctor_elements < num_type_elements)
2704 /* If there are "lots" of initialized elements, and all of them
2705 are valid address constants, then the entire initializer can
2706 be dropped to memory, and then memcpy'd out. Don't do this
2707 for sparse arrays, though, as it's more efficient to follow
2708 the standard CONSTRUCTOR behavior of memset followed by
2709 individual element initialization. */
2710 if (num_nonconstant_elements == 0 && !cleared)
2712 HOST_WIDE_INT size = int_size_in_bytes (type);
2715 /* ??? We can still get unbounded array types, at least
2716 from the C++ front end. This seems wrong, but attempt
2717 to work around it for now. */
2720 size = int_size_in_bytes (TREE_TYPE (object));
2722 TREE_TYPE (ctor) = type = TREE_TYPE (object);
2725 /* Find the maximum alignment we can assume for the object. */
2726 /* ??? Make use of DECL_OFFSET_ALIGN. */
2727 if (DECL_P (object))
2728 align = DECL_ALIGN (object);
2730 align = TYPE_ALIGN (type);
2732 if (size > 0 && !can_move_by_pieces (size, align))
2734 tree new = create_tmp_var_raw (type, "C");
2736 gimple_add_tmp_var (new);
2737 TREE_STATIC (new) = 1;
2738 TREE_READONLY (new) = 1;
2739 DECL_INITIAL (new) = ctor;
2740 if (align > DECL_ALIGN (new))
2742 DECL_ALIGN (new) = align;
2743 DECL_USER_ALIGN (new) = 1;
2745 walk_tree (&DECL_INITIAL (new), force_labels_r, NULL, NULL);
2747 TREE_OPERAND (*expr_p, 1) = new;
2749 /* This is no longer an assignment of a CONSTRUCTOR, but
2750 we still may have processing to do on the LHS. So
2751 pretend we didn't do anything here to let that happen. */
2752 return GS_UNHANDLED;
2758 /* Zap the CONSTRUCTOR element list, which simplifies this case.
2759 Note that we still have to gimplify, in order to handle the
2760 case of variable sized types. Avoid shared tree structures. */
2761 CONSTRUCTOR_ELTS (ctor) = NULL_TREE;
2762 object = unshare_expr (object);
2763 gimplify_stmt (expr_p);
2764 append_to_statement_list (*expr_p, pre_p);
2767 /* If we have not block cleared the object, or if there are nonzero
2768 elements in the constructor, add assignments to the individual
2769 scalar fields of the object. */
2770 if (!cleared || num_nonzero_elements > 0)
2772 preeval_data.lhs_base_decl = get_base_address (object);
2773 if (!DECL_P (preeval_data.lhs_base_decl))
2774 preeval_data.lhs_base_decl = NULL;
2775 preeval_data.lhs_alias_set = get_alias_set (object);
2777 gimplify_init_ctor_preeval (&TREE_OPERAND (*expr_p, 1),
2778 pre_p, post_p, &preeval_data);
2779 gimplify_init_ctor_eval (object, elt_list, pre_p, cleared);
2782 *expr_p = NULL_TREE;
2790 /* Extract the real and imaginary parts out of the ctor. */
2794 r = TREE_VALUE (elt_list);
2795 elt_list = TREE_CHAIN (elt_list);
2798 i = TREE_VALUE (elt_list);
2799 gcc_assert (!TREE_CHAIN (elt_list));
2802 if (r == NULL || i == NULL)
2804 tree zero = convert (TREE_TYPE (type), integer_zero_node);
2811 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
2812 represent creation of a complex value. */
2813 if (TREE_CONSTANT (r) && TREE_CONSTANT (i))
2815 ctor = build_complex (type, r, i);
2816 TREE_OPERAND (*expr_p, 1) = ctor;
2820 ctor = build (COMPLEX_EXPR, type, r, i);
2821 TREE_OPERAND (*expr_p, 1) = ctor;
2822 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
2823 rhs_predicate_for (TREE_OPERAND (*expr_p, 0)),
2830 /* Go ahead and simplify constant constructors to VECTOR_CST. */
2831 if (TREE_CONSTANT (ctor))
2835 /* Even when ctor is constant, it might contain non-*_CST
2836 elements (e.g. { 1.0/0.0 - 1.0/0.0, 0.0 }) and those don't
2837 belong into VECTOR_CST nodes. */
2838 for (tem = elt_list; tem; tem = TREE_CHAIN (tem))
2839 if (! CONSTANT_CLASS_P (TREE_VALUE (tem)))
2844 TREE_OPERAND (*expr_p, 1) = build_vector (type, elt_list);
2849 /* Vector types use CONSTRUCTOR all the way through gimple
2850 compilation as a general initializer. */
2851 for (; elt_list; elt_list = TREE_CHAIN (elt_list))
2853 enum gimplify_status tret;
2854 tret = gimplify_expr (&TREE_VALUE (elt_list), pre_p, post_p,
2855 is_gimple_val, fb_rvalue);
2856 if (tret == GS_ERROR)
2862 /* So how did we get a CONSTRUCTOR for a scalar type? */
2866 if (ret == GS_ERROR)
2868 else if (want_value)
2870 append_to_statement_list (*expr_p, pre_p);
2878 /* Given a pointer value OP0, return a simplified version of an
2879 indirection through OP0, or NULL_TREE if no simplification is
2880 possible. This may only be applied to a rhs of an expression.
2881 Note that the resulting type may be different from the type pointed
2882 to in the sense that it is still compatible from the langhooks
2886 fold_indirect_ref_rhs (tree t)
2888 tree type = TREE_TYPE (TREE_TYPE (t));
2893 subtype = TREE_TYPE (sub);
2894 if (!POINTER_TYPE_P (subtype))
2897 if (TREE_CODE (sub) == ADDR_EXPR)
2899 tree op = TREE_OPERAND (sub, 0);
2900 tree optype = TREE_TYPE (op);
2902 if (lang_hooks.types_compatible_p (type, optype))
2904 /* *(foo *)&fooarray => fooarray[0] */
2905 else if (TREE_CODE (optype) == ARRAY_TYPE
2906 && lang_hooks.types_compatible_p (type, TREE_TYPE (optype)))
2908 tree type_domain = TYPE_DOMAIN (optype);
2909 tree min_val = size_zero_node;
2910 if (type_domain && TYPE_MIN_VALUE (type_domain))
2911 min_val = TYPE_MIN_VALUE (type_domain);
2912 return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
2916 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
2917 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
2918 && lang_hooks.types_compatible_p (type, TREE_TYPE (TREE_TYPE (subtype))))
2921 tree min_val = size_zero_node;
2922 sub = fold_indirect_ref_rhs (sub);
2924 sub = build1 (INDIRECT_REF, TREE_TYPE (subtype), sub);
2925 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
2926 if (type_domain && TYPE_MIN_VALUE (type_domain))
2927 min_val = TYPE_MIN_VALUE (type_domain);
2928 return build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
2934 /* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs
2935 based on the code of the RHS. We loop for as long as something changes. */
2937 static enum gimplify_status
2938 gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p,
2939 tree *post_p, bool want_value)
2941 enum gimplify_status ret = GS_OK;
2943 while (ret != GS_UNHANDLED)
2944 switch (TREE_CODE (*from_p))
2948 /* If we have code like
2952 where the type of "x" is a (possibly cv-qualified variant
2953 of "A"), treat the entire expression as identical to "x".
2954 This kind of code arises in C++ when an object is bound
2955 to a const reference, and if "x" is a TARGET_EXPR we want
2956 to take advantage of the optimization below. */
2957 tree t = fold_indirect_ref_rhs (TREE_OPERAND (*from_p, 0));
2970 /* If we are initializing something from a TARGET_EXPR, strip the
2971 TARGET_EXPR and initialize it directly, if possible. This can't
2972 be done if the initializer is void, since that implies that the
2973 temporary is set in some non-trivial way.
2975 ??? What about code that pulls out the temp and uses it
2976 elsewhere? I think that such code never uses the TARGET_EXPR as
2977 an initializer. If I'm wrong, we'll die because the temp won't
2978 have any RTL. In that case, I guess we'll need to replace
2979 references somehow. */
2980 tree init = TARGET_EXPR_INITIAL (*from_p);
2982 if (!VOID_TYPE_P (TREE_TYPE (init)))
2993 /* Remove any COMPOUND_EXPR in the RHS so the following cases will be
2995 gimplify_compound_expr (from_p, pre_p, true);
3000 /* If we're initializing from a CONSTRUCTOR, break this into
3001 individual MODIFY_EXPRs. */
3002 return gimplify_init_constructor (expr_p, pre_p, post_p, want_value);
3005 /* If we're assigning to a non-register type, push the assignment
3006 down into the branches. This is mandatory for ADDRESSABLE types,
3007 since we cannot generate temporaries for such, but it saves a
3008 copy in other cases as well. */
3009 if (!is_gimple_reg_type (TREE_TYPE (*from_p)))
3012 return gimplify_cond_expr (expr_p, pre_p, post_p, *to_p,
3020 /* For calls that return in memory, give *to_p as the CALL_EXPR's
3021 return slot so that we don't generate a temporary. */
3022 if (!CALL_EXPR_RETURN_SLOT_OPT (*from_p)
3023 && aggregate_value_p (*from_p, *from_p))
3027 if (TREE_CODE (*to_p) == RESULT_DECL
3028 && needs_to_live_in_memory (*to_p))
3029 /* It's always OK to use the return slot directly. */
3031 else if (!is_gimple_non_addressable (*to_p))
3032 /* Don't use the original target if it's already addressable;
3033 if its address escapes, and the called function uses the
3034 NRV optimization, a conforming program could see *to_p
3035 change before the called function returns; see c++/19317.
3036 When optimizing, the return_slot pass marks more functions
3037 as safe after we have escape info. */
3039 else if (TREE_CODE (*to_p) != PARM_DECL
3040 && DECL_GIMPLE_FORMAL_TEMP_P (*to_p))
3041 /* Don't use the original target if it's a formal temp; we
3042 don't want to take their addresses. */
3044 else if (is_gimple_reg_type (TREE_TYPE (*to_p)))
3045 /* Also don't force regs into memory. */
3052 CALL_EXPR_RETURN_SLOT_OPT (*from_p) = 1;
3053 lang_hooks.mark_addressable (*to_p);
3068 /* Promote partial stores to COMPLEX variables to total stores. *EXPR_P is
3069 a MODIFY_EXPR with a lhs of a REAL/IMAGPART_EXPR of a variable with
3070 DECL_COMPLEX_GIMPLE_REG_P set. */
3072 static enum gimplify_status
3073 gimplify_modify_expr_complex_part (tree *expr_p, tree *pre_p, bool want_value)
3075 enum tree_code code, ocode;
3076 tree lhs, rhs, new_rhs, other, realpart, imagpart;
3078 lhs = TREE_OPERAND (*expr_p, 0);
3079 rhs = TREE_OPERAND (*expr_p, 1);
3080 code = TREE_CODE (lhs);
3081 lhs = TREE_OPERAND (lhs, 0);
3083 ocode = code == REALPART_EXPR ? IMAGPART_EXPR : REALPART_EXPR;
3084 other = build1 (ocode, TREE_TYPE (rhs), lhs);
3085 other = get_formal_tmp_var (other, pre_p);
3087 realpart = code == REALPART_EXPR ? rhs : other;
3088 imagpart = code == REALPART_EXPR ? other : rhs;
3090 if (TREE_CONSTANT (realpart) && TREE_CONSTANT (imagpart))
3091 new_rhs = build_complex (TREE_TYPE (lhs), realpart, imagpart);
3093 new_rhs = build2 (COMPLEX_EXPR, TREE_TYPE (lhs), realpart, imagpart);
3095 TREE_OPERAND (*expr_p, 0) = lhs;
3096 TREE_OPERAND (*expr_p, 1) = new_rhs;
3100 append_to_statement_list (*expr_p, pre_p);
3107 /* Gimplify the MODIFY_EXPR node pointed by EXPR_P.
3113 PRE_P points to the list where side effects that must happen before
3114 *EXPR_P should be stored.
3116 POST_P points to the list where side effects that must happen after
3117 *EXPR_P should be stored.
3119 WANT_VALUE is nonzero iff we want to use the value of this expression
3120 in another expression. */
3122 static enum gimplify_status
3123 gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value)
3125 tree *from_p = &TREE_OPERAND (*expr_p, 1);
3126 tree *to_p = &TREE_OPERAND (*expr_p, 0);
3127 enum gimplify_status ret = GS_UNHANDLED;
3129 gcc_assert (TREE_CODE (*expr_p) == MODIFY_EXPR
3130 || TREE_CODE (*expr_p) == INIT_EXPR);
3132 /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer useful. */
3133 if (TREE_CODE (*expr_p) == INIT_EXPR)
3134 TREE_SET_CODE (*expr_p, MODIFY_EXPR);
3136 /* See if any simplifications can be done based on what the RHS is. */
3137 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
3139 if (ret != GS_UNHANDLED)
3142 /* If the value being copied is of variable width, compute the length
3143 of the copy into a WITH_SIZE_EXPR. Note that we need to do this
3144 before gimplifying any of the operands so that we can resolve any
3145 PLACEHOLDER_EXPRs in the size. Also note that the RTL expander uses
3146 the size of the expression to be copied, not of the destination, so
3147 that is what we must here. */
3148 maybe_with_size_expr (from_p);
3150 ret = gimplify_expr (to_p, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
3151 if (ret == GS_ERROR)
3154 ret = gimplify_expr (from_p, pre_p, post_p,
3155 rhs_predicate_for (*to_p), fb_rvalue);
3156 if (ret == GS_ERROR)
3159 /* Now see if the above changed *from_p to something we handle specially. */
3160 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
3162 if (ret != GS_UNHANDLED)
3165 /* If we've got a variable sized assignment between two lvalues (i.e. does
3166 not involve a call), then we can make things a bit more straightforward
3167 by converting the assignment to memcpy or memset. */
3168 if (TREE_CODE (*from_p) == WITH_SIZE_EXPR)
3170 tree from = TREE_OPERAND (*from_p, 0);
3171 tree size = TREE_OPERAND (*from_p, 1);
3173 if (TREE_CODE (from) == CONSTRUCTOR)
3174 return gimplify_modify_expr_to_memset (expr_p, size, want_value);
3175 if (is_gimple_addressable (from))
3178 return gimplify_modify_expr_to_memcpy (expr_p, size, want_value);
3182 /* Transform partial stores to non-addressable complex variables into
3183 total stores. This allows us to use real instead of virtual operands
3184 for these variables, which improves optimization. */
3185 if ((TREE_CODE (*to_p) == REALPART_EXPR
3186 || TREE_CODE (*to_p) == IMAGPART_EXPR)
3187 && is_gimple_reg (TREE_OPERAND (*to_p, 0)))
3188 return gimplify_modify_expr_complex_part (expr_p, pre_p, want_value);
3190 if (gimplify_ctxp->into_ssa && is_gimple_reg (*to_p))
3192 /* If we've somehow already got an SSA_NAME on the LHS, then
3193 we're probably modified it twice. Not good. */
3194 gcc_assert (TREE_CODE (*to_p) != SSA_NAME);
3195 *to_p = make_ssa_name (*to_p, *expr_p);
3200 append_to_statement_list (*expr_p, pre_p);
3208 /* Gimplify a comparison between two variable-sized objects. Do this
3209 with a call to BUILT_IN_MEMCMP. */
3211 static enum gimplify_status
3212 gimplify_variable_sized_compare (tree *expr_p)
3214 tree op0 = TREE_OPERAND (*expr_p, 0);
3215 tree op1 = TREE_OPERAND (*expr_p, 1);
3218 t = TYPE_SIZE_UNIT (TREE_TYPE (op0));
3219 t = unshare_expr (t);
3220 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, op0);
3221 args = tree_cons (NULL, t, NULL);
3222 t = build_fold_addr_expr (op1);
3223 args = tree_cons (NULL, t, args);
3224 dest = build_fold_addr_expr (op0);
3225 args = tree_cons (NULL, dest, args);
3226 t = implicit_built_in_decls[BUILT_IN_MEMCMP];
3227 t = build_function_call_expr (t, args);
3229 = build (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), t, integer_zero_node);
3234 /* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P
3235 points to the expression to gimplify.
3237 Expressions of the form 'a && b' are gimplified to:
3239 a && b ? true : false
3241 gimplify_cond_expr will do the rest.
3243 PRE_P points to the list where side effects that must happen before
3244 *EXPR_P should be stored. */
3246 static enum gimplify_status
3247 gimplify_boolean_expr (tree *expr_p)
3249 /* Preserve the original type of the expression. */
3250 tree type = TREE_TYPE (*expr_p);
3252 *expr_p = build (COND_EXPR, type, *expr_p,
3253 convert (type, boolean_true_node),
3254 convert (type, boolean_false_node));
3259 /* Gimplifies an expression sequence. This function gimplifies each
3260 expression and re-writes the original expression with the last
3261 expression of the sequence in GIMPLE form.
3263 PRE_P points to the list where the side effects for all the
3264 expressions in the sequence will be emitted.
3266 WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */
3267 /* ??? Should rearrange to share the pre-queue with all the indirect
3268 invocations of gimplify_expr. Would probably save on creations
3269 of statement_list nodes. */
3271 static enum gimplify_status
3272 gimplify_compound_expr (tree *expr_p, tree *pre_p, bool want_value)
3278 tree *sub_p = &TREE_OPERAND (t, 0);
3280 if (TREE_CODE (*sub_p) == COMPOUND_EXPR)
3281 gimplify_compound_expr (sub_p, pre_p, false);
3283 gimplify_stmt (sub_p);
3284 append_to_statement_list (*sub_p, pre_p);
3286 t = TREE_OPERAND (t, 1);
3288 while (TREE_CODE (t) == COMPOUND_EXPR);
3295 gimplify_stmt (expr_p);
3300 /* Gimplifies a statement list. These may be created either by an
3301 enlightened front-end, or by shortcut_cond_expr. */
3303 static enum gimplify_status
3304 gimplify_statement_list (tree *expr_p)
3306 tree_stmt_iterator i = tsi_start (*expr_p);
3308 while (!tsi_end_p (i))
3312 gimplify_stmt (tsi_stmt_ptr (i));
3317 else if (TREE_CODE (t) == STATEMENT_LIST)
3319 tsi_link_before (&i, t, TSI_SAME_STMT);
3329 /* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to
3330 gimplify. After gimplification, EXPR_P will point to a new temporary
3331 that holds the original value of the SAVE_EXPR node.
3333 PRE_P points to the list where side effects that must happen before
3334 *EXPR_P should be stored. */
3336 static enum gimplify_status
3337 gimplify_save_expr (tree *expr_p, tree *pre_p, tree *post_p)
3339 enum gimplify_status ret = GS_ALL_DONE;
3342 gcc_assert (TREE_CODE (*expr_p) == SAVE_EXPR);
3343 val = TREE_OPERAND (*expr_p, 0);
3345 /* If the SAVE_EXPR has not been resolved, then evaluate it once. */
3346 if (!SAVE_EXPR_RESOLVED_P (*expr_p))
3348 /* The operand may be a void-valued expression such as SAVE_EXPRs
3349 generated by the Java frontend for class initialization. It is
3350 being executed only for its side-effects. */
3351 if (TREE_TYPE (val) == void_type_node)
3353 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3354 is_gimple_stmt, fb_none);
3355 append_to_statement_list (TREE_OPERAND (*expr_p, 0), pre_p);
3359 val = get_initialized_tmp_var (val, pre_p, post_p);
3361 TREE_OPERAND (*expr_p, 0) = val;
3362 SAVE_EXPR_RESOLVED_P (*expr_p) = 1;
3370 /* Re-write the ADDR_EXPR node pointed by EXPR_P
3377 PRE_P points to the list where side effects that must happen before
3378 *EXPR_P should be stored.
3380 POST_P points to the list where side effects that must happen after
3381 *EXPR_P should be stored. */
3383 static enum gimplify_status
3384 gimplify_addr_expr (tree *expr_p, tree *pre_p, tree *post_p)
3386 tree expr = *expr_p;
3387 tree op0 = TREE_OPERAND (expr, 0);
3388 enum gimplify_status ret;
3390 switch (TREE_CODE (op0))
3393 case MISALIGNED_INDIRECT_REF:
3395 /* Check if we are dealing with an expression of the form '&*ptr'.
3396 While the front end folds away '&*ptr' into 'ptr', these
3397 expressions may be generated internally by the compiler (e.g.,
3398 builtins like __builtin_va_end). */
3399 /* Caution: the silent array decomposition semantics we allow for
3400 ADDR_EXPR means we can't always discard the pair. */
3401 /* Gimplification of the ADDR_EXPR operand may drop
3402 cv-qualification conversions, so make sure we add them if
3405 tree op00 = TREE_OPERAND (op0, 0);
3406 tree t_expr = TREE_TYPE (expr);
3407 tree t_op00 = TREE_TYPE (op00);
3409 if (!lang_hooks.types_compatible_p (t_expr, t_op00))
3411 #ifdef ENABLE_CHECKING
3412 tree t_op0 = TREE_TYPE (op0);
3413 gcc_assert (POINTER_TYPE_P (t_expr)
3414 && cpt_same_type (TREE_CODE (t_op0) == ARRAY_TYPE
3415 ? TREE_TYPE (t_op0) : t_op0,
3417 && POINTER_TYPE_P (t_op00)
3418 && cpt_same_type (t_op0, TREE_TYPE (t_op00)));
3420 op00 = fold_convert (TREE_TYPE (expr), op00);
3427 case VIEW_CONVERT_EXPR:
3428 /* Take the address of our operand and then convert it to the type of
3431 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3432 all clear. The impact of this transformation is even less clear. */
3434 /* If the operand is a useless conversion, look through it. Doing so
3435 guarantees that the ADDR_EXPR and its operand will remain of the
3437 if (tree_ssa_useless_type_conversion (TREE_OPERAND (op0, 0)))
3438 op0 = TREE_OPERAND (op0, 0);
3440 *expr_p = fold_convert (TREE_TYPE (expr),
3441 build_fold_addr_expr (TREE_OPERAND (op0, 0)));
3446 /* We use fb_either here because the C frontend sometimes takes
3447 the address of a call that returns a struct; see
3448 gcc.dg/c99-array-lval-1.c. The gimplifier will correctly make
3449 the implied temporary explicit. */
3450 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, post_p,
3451 is_gimple_addressable, fb_either);
3452 if (ret != GS_ERROR)
3454 op0 = TREE_OPERAND (expr, 0);
3456 /* For various reasons, the gimplification of the expression
3457 may have made a new INDIRECT_REF. */
3458 if (TREE_CODE (op0) == INDIRECT_REF)
3459 goto do_indirect_ref;
3461 /* Make sure TREE_INVARIANT, TREE_CONSTANT, and TREE_SIDE_EFFECTS
3463 recompute_tree_invarant_for_addr_expr (expr);
3465 /* Mark the RHS addressable. */
3466 lang_hooks.mark_addressable (TREE_OPERAND (expr, 0));
3474 /* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple
3475 value; output operands should be a gimple lvalue. */
3477 static enum gimplify_status
3478 gimplify_asm_expr (tree *expr_p, tree *pre_p, tree *post_p)
3480 tree expr = *expr_p;
3481 int noutputs = list_length (ASM_OUTPUTS (expr));
3482 const char **oconstraints
3483 = (const char **) alloca ((noutputs) * sizeof (const char *));
3486 const char *constraint;
3487 bool allows_mem, allows_reg, is_inout;
3488 enum gimplify_status ret, tret;
3491 for (i = 0, link = ASM_OUTPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3493 size_t constraint_len;
3494 oconstraints[i] = constraint
3495 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3496 constraint_len = strlen (constraint);
3497 if (constraint_len == 0)
3500 parse_output_constraint (&constraint, i, 0, 0,
3501 &allows_mem, &allows_reg, &is_inout);
3503 if (!allows_reg && allows_mem)
3504 lang_hooks.mark_addressable (TREE_VALUE (link));
3506 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3507 is_inout ? is_gimple_min_lval : is_gimple_lvalue,
3508 fb_lvalue | fb_mayfail);
3509 if (tret == GS_ERROR)
3511 error ("invalid lvalue in asm output %d", i);
3517 /* An input/output operand. To give the optimizers more
3518 flexibility, split it into separate input and output
3523 /* Turn the in/out constraint into an output constraint. */
3524 char *p = xstrdup (constraint);
3526 TREE_VALUE (TREE_PURPOSE (link)) = build_string (constraint_len, p);
3528 /* And add a matching input constraint. */
3531 sprintf (buf, "%d", i);
3533 /* If there are multiple alternatives in the constraint,
3534 handle each of them individually. Those that allow register
3535 will be replaced with operand number, the others will stay
3537 if (strchr (p, ',') != NULL)
3539 size_t len = 0, buflen = strlen (buf);
3540 char *beg, *end, *str, *dst;
3544 end = strchr (beg, ',');
3546 end = strchr (beg, '\0');
3547 if ((size_t) (end - beg) < buflen)
3550 len += end - beg + 1;
3558 for (beg = p + 1, dst = str;;)
3561 bool mem_p, reg_p, inout_p;
3563 end = strchr (beg, ',');
3568 parse_output_constraint (&tem, i, 0, 0,
3569 &mem_p, ®_p, &inout_p);
3574 memcpy (dst, buf, buflen);
3583 memcpy (dst, beg, len);
3592 input = build_string (dst - str, str);
3595 input = build_string (strlen (buf), buf);
3598 input = build_string (constraint_len - 1, constraint + 1);
3602 input = build_tree_list (build_tree_list (NULL_TREE, input),
3603 unshare_expr (TREE_VALUE (link)));
3604 ASM_INPUTS (expr) = chainon (ASM_INPUTS (expr), input);
3608 for (link = ASM_INPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3611 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3612 parse_input_constraint (&constraint, 0, 0, noutputs, 0,
3613 oconstraints, &allows_mem, &allows_reg);
3615 /* If the operand is a memory input, it should be an lvalue. */
3616 if (!allows_reg && allows_mem)
3618 lang_hooks.mark_addressable (TREE_VALUE (link));
3619 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3620 is_gimple_lvalue, fb_lvalue | fb_mayfail);
3621 if (tret == GS_ERROR)
3623 error ("memory input %d is not directly addressable", i);
3629 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3630 is_gimple_asm_val, fb_rvalue);
3631 if (tret == GS_ERROR)
3639 /* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding
3640 WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
3641 gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
3642 return to this function.
3644 FIXME should we complexify the prequeue handling instead? Or use flags
3645 for all the cleanups and let the optimizer tighten them up? The current
3646 code seems pretty fragile; it will break on a cleanup within any
3647 non-conditional nesting. But any such nesting would be broken, anyway;
3648 we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
3649 and continues out of it. We can do that at the RTL level, though, so
3650 having an optimizer to tighten up try/finally regions would be a Good
3653 static enum gimplify_status
3654 gimplify_cleanup_point_expr (tree *expr_p, tree *pre_p)
3656 tree_stmt_iterator iter;
3659 tree temp = voidify_wrapper_expr (*expr_p, NULL);
3661 /* We only care about the number of conditions between the innermost
3662 CLEANUP_POINT_EXPR and the cleanup. So save and reset the count. */
3663 int old_conds = gimplify_ctxp->conditions;
3664 gimplify_ctxp->conditions = 0;
3666 body = TREE_OPERAND (*expr_p, 0);
3667 gimplify_to_stmt_list (&body);
3669 gimplify_ctxp->conditions = old_conds;
3671 for (iter = tsi_start (body); !tsi_end_p (iter); )
3673 tree *wce_p = tsi_stmt_ptr (iter);
3676 if (TREE_CODE (wce) == WITH_CLEANUP_EXPR)
3678 if (tsi_one_before_end_p (iter))
3680 tsi_link_before (&iter, TREE_OPERAND (wce, 0), TSI_SAME_STMT);
3687 enum tree_code code;
3689 if (CLEANUP_EH_ONLY (wce))
3690 code = TRY_CATCH_EXPR;
3692 code = TRY_FINALLY_EXPR;
3694 sl = tsi_split_statement_list_after (&iter);
3695 tfe = build (code, void_type_node, sl, NULL_TREE);
3696 append_to_statement_list (TREE_OPERAND (wce, 0),
3697 &TREE_OPERAND (tfe, 1));
3699 iter = tsi_start (sl);
3709 append_to_statement_list (body, pre_p);
3719 /* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP
3720 is the cleanup action required. */
3723 gimple_push_cleanup (tree var, tree cleanup, bool eh_only, tree *pre_p)
3727 /* Errors can result in improperly nested cleanups. Which results in
3728 confusion when trying to resolve the WITH_CLEANUP_EXPR. */
3729 if (errorcount || sorrycount)
3732 if (gimple_conditional_context ())
3734 /* If we're in a conditional context, this is more complex. We only
3735 want to run the cleanup if we actually ran the initialization that
3736 necessitates it, but we want to run it after the end of the
3737 conditional context. So we wrap the try/finally around the
3738 condition and use a flag to determine whether or not to actually
3739 run the destructor. Thus
3743 becomes (approximately)
3747 if (test) { A::A(temp); flag = 1; val = f(temp); }
3750 if (flag) A::~A(temp);
3755 tree flag = create_tmp_var (boolean_type_node, "cleanup");
3756 tree ffalse = build (MODIFY_EXPR, void_type_node, flag,
3757 boolean_false_node);
3758 tree ftrue = build (MODIFY_EXPR, void_type_node, flag,
3760 cleanup = build (COND_EXPR, void_type_node, flag, cleanup, NULL);
3761 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3762 append_to_statement_list (ffalse, &gimplify_ctxp->conditional_cleanups);
3763 append_to_statement_list (wce, &gimplify_ctxp->conditional_cleanups);
3764 append_to_statement_list (ftrue, pre_p);
3766 /* Because of this manipulation, and the EH edges that jump
3767 threading cannot redirect, the temporary (VAR) will appear
3768 to be used uninitialized. Don't warn. */
3769 TREE_NO_WARNING (var) = 1;
3773 wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
3774 CLEANUP_EH_ONLY (wce) = eh_only;
3775 append_to_statement_list (wce, pre_p);
3778 gimplify_stmt (&TREE_OPERAND (wce, 0));
3781 /* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */
3783 static enum gimplify_status
3784 gimplify_target_expr (tree *expr_p, tree *pre_p, tree *post_p)
3786 tree targ = *expr_p;
3787 tree temp = TARGET_EXPR_SLOT (targ);
3788 tree init = TARGET_EXPR_INITIAL (targ);
3789 enum gimplify_status ret;
3793 /* TARGET_EXPR temps aren't part of the enclosing block, so add it
3794 to the temps list. */
3795 gimple_add_tmp_var (temp);
3797 /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
3798 expression is supposed to initialize the slot. */
3799 if (VOID_TYPE_P (TREE_TYPE (init)))
3800 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, fb_none);
3803 /* Special handling for BIND_EXPR can result in fewer temps. */
3805 if (TREE_CODE (init) == BIND_EXPR)
3806 gimplify_bind_expr (&init, temp, pre_p);
3809 init = build (MODIFY_EXPR, void_type_node, temp, init);
3810 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt,
3814 if (ret == GS_ERROR)
3816 append_to_statement_list (init, pre_p);
3818 /* If needed, push the cleanup for the temp. */
3819 if (TARGET_EXPR_CLEANUP (targ))
3821 gimplify_stmt (&TARGET_EXPR_CLEANUP (targ));
3822 gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ),
3823 CLEANUP_EH_ONLY (targ), pre_p);
3826 /* Only expand this once. */
3827 TREE_OPERAND (targ, 3) = init;
3828 TARGET_EXPR_INITIAL (targ) = NULL_TREE;
3831 /* We should have expanded this before. */
3832 gcc_assert (DECL_SEEN_IN_BIND_EXPR_P (temp));
3838 /* Gimplification of expression trees. */
3840 /* Gimplify an expression which appears at statement context; usually, this
3841 means replacing it with a suitably gimple STATEMENT_LIST. */
3844 gimplify_stmt (tree *stmt_p)
3846 gimplify_expr (stmt_p, NULL, NULL, is_gimple_stmt, fb_none);
3849 /* Similarly, but force the result to be a STATEMENT_LIST. */
3852 gimplify_to_stmt_list (tree *stmt_p)
3854 gimplify_stmt (stmt_p);
3856 *stmt_p = alloc_stmt_list ();
3857 else if (TREE_CODE (*stmt_p) != STATEMENT_LIST)
3860 *stmt_p = alloc_stmt_list ();
3861 append_to_statement_list (t, stmt_p);
3866 /* Gimplifies the expression tree pointed by EXPR_P. Return 0 if
3867 gimplification failed.
3869 PRE_P points to the list where side effects that must happen before
3870 EXPR should be stored.
3872 POST_P points to the list where side effects that must happen after
3873 EXPR should be stored, or NULL if there is no suitable list. In
3874 that case, we copy the result to a temporary, emit the
3875 post-effects, and then return the temporary.
3877 GIMPLE_TEST_F points to a function that takes a tree T and
3878 returns nonzero if T is in the GIMPLE form requested by the
3879 caller. The GIMPLE predicates are in tree-gimple.c.
3881 This test is used twice. Before gimplification, the test is
3882 invoked to determine whether *EXPR_P is already gimple enough. If
3883 that fails, *EXPR_P is gimplified according to its code and
3884 GIMPLE_TEST_F is called again. If the test still fails, then a new
3885 temporary variable is created and assigned the value of the
3886 gimplified expression.
3888 FALLBACK tells the function what sort of a temporary we want. If the 1
3889 bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK.
3890 If both are set, either is OK, but an lvalue is preferable.
3892 The return value is either GS_ERROR or GS_ALL_DONE, since this function
3893 iterates until solution. */
3895 enum gimplify_status
3896 gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
3897 bool (* gimple_test_f) (tree), fallback_t fallback)
3900 tree internal_pre = NULL_TREE;
3901 tree internal_post = NULL_TREE;
3903 int is_statement = (pre_p == NULL);
3904 location_t saved_location;
3905 enum gimplify_status ret;
3907 save_expr = *expr_p;
3908 if (save_expr == NULL_TREE)
3911 /* We used to check the predicate here and return immediately if it
3912 succeeds. This is wrong; the design is for gimplification to be
3913 idempotent, and for the predicates to only test for valid forms, not
3914 whether they are fully simplified. */
3916 /* Set up our internal queues if needed. */
3918 pre_p = &internal_pre;
3920 post_p = &internal_post;
3922 saved_location = input_location;
3923 if (save_expr != error_mark_node
3924 && EXPR_HAS_LOCATION (*expr_p))
3925 input_location = EXPR_LOCATION (*expr_p);
3927 /* Loop over the specific gimplifiers until the toplevel node
3928 remains the same. */
3931 /* Strip away as many useless type conversions as possible
3933 STRIP_USELESS_TYPE_CONVERSION (*expr_p);
3935 /* Remember the expr. */
3936 save_expr = *expr_p;
3938 /* Die, die, die, my darling. */
3939 if (save_expr == error_mark_node
3940 || (TREE_TYPE (save_expr)
3941 && TREE_TYPE (save_expr) == error_mark_node))
3947 /* Do any language-specific gimplification. */
3948 ret = lang_hooks.gimplify_expr (expr_p, pre_p, post_p);
3951 if (*expr_p == NULL_TREE)
3953 if (*expr_p != save_expr)
3956 else if (ret != GS_UNHANDLED)
3960 switch (TREE_CODE (*expr_p))
3962 /* First deal with the special cases. */
3964 case POSTINCREMENT_EXPR:
3965 case POSTDECREMENT_EXPR:
3966 case PREINCREMENT_EXPR:
3967 case PREDECREMENT_EXPR:
3968 ret = gimplify_self_mod_expr (expr_p, pre_p, post_p,
3969 fallback != fb_none);
3973 case ARRAY_RANGE_REF:
3977 case VIEW_CONVERT_EXPR:
3978 ret = gimplify_compound_lval (expr_p, pre_p, post_p,
3979 fallback ? fallback : fb_rvalue);
3983 ret = gimplify_cond_expr (expr_p, pre_p, post_p, NULL_TREE,
3985 /* C99 code may assign to an array in a structure value of a
3986 conditional expression, and this has undefined behavior
3987 only on execution, so create a temporary if an lvalue is
3989 if (fallback == fb_lvalue)
3991 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
3992 lang_hooks.mark_addressable (*expr_p);
3997 ret = gimplify_call_expr (expr_p, pre_p, fallback != fb_none);
3998 /* C99 code may assign to an array in a structure returned
3999 from a function, and this has undefined behavior only on
4000 execution, so create a temporary if an lvalue is
4002 if (fallback == fb_lvalue)
4004 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
4005 lang_hooks.mark_addressable (*expr_p);
4013 ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none);
4018 ret = gimplify_modify_expr (expr_p, pre_p, post_p,
4019 fallback != fb_none);
4022 case TRUTH_ANDIF_EXPR:
4023 case TRUTH_ORIF_EXPR:
4024 ret = gimplify_boolean_expr (expr_p);
4027 case TRUTH_NOT_EXPR:
4028 TREE_OPERAND (*expr_p, 0)
4029 = gimple_boolify (TREE_OPERAND (*expr_p, 0));
4030 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4031 is_gimple_val, fb_rvalue);
4032 recalculate_side_effects (*expr_p);
4036 ret = gimplify_addr_expr (expr_p, pre_p, post_p);
4040 ret = gimplify_va_arg_expr (expr_p, pre_p, post_p);
4045 if (IS_EMPTY_STMT (*expr_p))
4051 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
4052 || fallback == fb_none)
4054 /* Just strip a conversion to void (or in void context) and
4056 *expr_p = TREE_OPERAND (*expr_p, 0);
4060 ret = gimplify_conversion (expr_p);
4061 if (ret == GS_ERROR)
4063 if (*expr_p != save_expr)
4067 case FIX_TRUNC_EXPR:
4069 case FIX_FLOOR_EXPR:
4070 case FIX_ROUND_EXPR:
4071 /* unary_expr: ... | '(' cast ')' val | ... */
4072 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4073 is_gimple_val, fb_rvalue);
4074 recalculate_side_effects (*expr_p);
4078 *expr_p = fold_indirect_ref (*expr_p);
4079 if (*expr_p != save_expr)
4081 /* else fall through. */
4082 case ALIGN_INDIRECT_REF:
4083 case MISALIGNED_INDIRECT_REF:
4084 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4085 is_gimple_reg, fb_rvalue);
4086 recalculate_side_effects (*expr_p);
4089 /* Constants need not be gimplified. */
4099 /* If we require an lvalue, such as for ADDR_EXPR, retain the
4100 CONST_DECL node. Otherwise the decl is replaceable by its
4102 /* ??? Should be == fb_lvalue, but ADDR_EXPR passes fb_either. */
4103 if (fallback & fb_lvalue)
4106 *expr_p = DECL_INITIAL (*expr_p);
4110 ret = gimplify_decl_expr (expr_p);
4114 /* FIXME make this a decl. */
4119 ret = gimplify_bind_expr (expr_p, NULL, pre_p);
4123 ret = gimplify_loop_expr (expr_p, pre_p);
4127 ret = gimplify_switch_expr (expr_p, pre_p);
4131 ret = gimplify_exit_expr (expr_p);
4135 /* If the target is not LABEL, then it is a computed jump
4136 and the target needs to be gimplified. */
4137 if (TREE_CODE (GOTO_DESTINATION (*expr_p)) != LABEL_DECL)
4138 ret = gimplify_expr (&GOTO_DESTINATION (*expr_p), pre_p,
4139 NULL, is_gimple_val, fb_rvalue);
4144 gcc_assert (decl_function_context (LABEL_EXPR_LABEL (*expr_p))
4145 == current_function_decl);
4148 case CASE_LABEL_EXPR:
4149 ret = gimplify_case_label_expr (expr_p);
4153 ret = gimplify_return_expr (*expr_p, pre_p);
4157 /* Don't reduce this in place; let gimplify_init_constructor work its
4158 magic. Buf if we're just elaborating this for side effects, just
4159 gimplify any element that has side-effects. */
4160 if (fallback == fb_none)
4162 for (tmp = CONSTRUCTOR_ELTS (*expr_p); tmp;
4163 tmp = TREE_CHAIN (tmp))
4164 if (TREE_SIDE_EFFECTS (TREE_VALUE (tmp)))
4165 gimplify_expr (&TREE_VALUE (tmp), pre_p, post_p,
4166 gimple_test_f, fallback);
4168 *expr_p = NULL_TREE;
4174 /* The following are special cases that are not handled by the
4175 original GIMPLE grammar. */
4177 /* SAVE_EXPR nodes are converted into a GIMPLE identifier and
4180 ret = gimplify_save_expr (expr_p, pre_p, post_p);
4185 enum gimplify_status r0, r1, r2;
4187 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4188 is_gimple_lvalue, fb_either);
4189 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
4190 is_gimple_val, fb_rvalue);
4191 r2 = gimplify_expr (&TREE_OPERAND (*expr_p, 2), pre_p, post_p,
4192 is_gimple_val, fb_rvalue);
4193 recalculate_side_effects (*expr_p);
4195 ret = MIN (r0, MIN (r1, r2));
4199 case NON_LVALUE_EXPR:
4200 /* This should have been stripped above. */
4204 ret = gimplify_asm_expr (expr_p, pre_p, post_p);
4207 case TRY_FINALLY_EXPR:
4208 case TRY_CATCH_EXPR:
4209 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 0));
4210 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 1));
4214 case CLEANUP_POINT_EXPR:
4215 ret = gimplify_cleanup_point_expr (expr_p, pre_p);
4219 ret = gimplify_target_expr (expr_p, pre_p, post_p);
4223 gimplify_to_stmt_list (&CATCH_BODY (*expr_p));
4227 case EH_FILTER_EXPR:
4228 gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p));
4234 enum gimplify_status r0, r1;
4235 r0 = gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p), pre_p, post_p,
4236 is_gimple_val, fb_rvalue);
4237 r1 = gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p), pre_p, post_p,
4238 is_gimple_val, fb_rvalue);
4244 /* We get here when taking the address of a label. We mark
4245 the label as "forced"; meaning it can never be removed and
4246 it is a potential target for any computed goto. */
4247 FORCED_LABEL (*expr_p) = 1;
4251 case STATEMENT_LIST:
4252 ret = gimplify_statement_list (expr_p);
4255 case WITH_SIZE_EXPR:
4257 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
4258 post_p == &internal_post ? NULL : post_p,
4259 gimple_test_f, fallback);
4260 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
4261 is_gimple_val, fb_rvalue);
4266 /* ??? If this is a local variable, and it has not been seen in any
4267 outer BIND_EXPR, then it's probably the result of a duplicate
4268 declaration, for which we've already issued an error. It would
4269 be really nice if the front end wouldn't leak these at all.
4270 Currently the only known culprit is C++ destructors, as seen
4271 in g++.old-deja/g++.jason/binding.C. */
4273 if (!TREE_STATIC (tmp) && !DECL_EXTERNAL (tmp)
4274 && decl_function_context (tmp) == current_function_decl
4275 && !DECL_SEEN_IN_BIND_EXPR_P (tmp))
4277 gcc_assert (errorcount || sorrycount);
4286 /* If this is a local variable sized decl, it must be accessed
4287 indirectly. Perform that substitution. */
4288 if (DECL_HAS_VALUE_EXPR_P (tmp))
4290 *expr_p = unshare_expr (DECL_VALUE_EXPR (tmp));
4299 /* Allow callbacks into the gimplifier during optimization. */
4304 switch (TREE_CODE_CLASS (TREE_CODE (*expr_p)))
4306 case tcc_comparison:
4307 /* If this is a comparison of objects of aggregate type,
4308 handle it specially (by converting to a call to
4309 memcmp). It would be nice to only have to do this
4310 for variable-sized objects, but then we'd have to
4311 allow the same nest of reference nodes we allow for
4312 MODIFY_EXPR and that's too complex. */
4313 if (!AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 1))))
4315 ret = gimplify_variable_sized_compare (expr_p);
4318 /* If *EXPR_P does not need to be special-cased, handle it
4319 according to its class. */
4321 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
4322 post_p, is_gimple_val, fb_rvalue);
4328 enum gimplify_status r0, r1;
4330 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
4331 post_p, is_gimple_val, fb_rvalue);
4332 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p,
4333 post_p, is_gimple_val, fb_rvalue);
4339 case tcc_declaration:
4342 goto dont_recalculate;
4345 gcc_assert (TREE_CODE (*expr_p) == TRUTH_AND_EXPR
4346 || TREE_CODE (*expr_p) == TRUTH_OR_EXPR
4347 || TREE_CODE (*expr_p) == TRUTH_XOR_EXPR);
4351 recalculate_side_effects (*expr_p);
4356 /* If we replaced *expr_p, gimplify again. */
4357 if (ret == GS_OK && (*expr_p == NULL || *expr_p == save_expr))
4360 while (ret == GS_OK);
4362 /* If we encountered an error_mark somewhere nested inside, either
4363 stub out the statement or propagate the error back out. */
4364 if (ret == GS_ERROR)
4371 /* This was only valid as a return value from the langhook, which
4372 we handled. Make sure it doesn't escape from any other context. */
4373 gcc_assert (ret != GS_UNHANDLED);
4375 if (fallback == fb_none && *expr_p && !is_gimple_stmt (*expr_p))
4377 /* We aren't looking for a value, and we don't have a valid
4378 statement. If it doesn't have side-effects, throw it away. */
4379 if (!TREE_SIDE_EFFECTS (*expr_p))
4381 else if (!TREE_THIS_VOLATILE (*expr_p))
4383 /* This is probably a _REF that contains something nested that
4384 has side effects. Recurse through the operands to find it. */
4385 enum tree_code code = TREE_CODE (*expr_p);
4390 case REALPART_EXPR: case IMAGPART_EXPR:
4391 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4392 gimple_test_f, fallback);
4395 case ARRAY_REF: case ARRAY_RANGE_REF:
4396 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
4397 gimple_test_f, fallback);
4398 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
4399 gimple_test_f, fallback);
4403 /* Anything else with side-effects must be converted to
4404 a valid statement before we get here. */
4410 else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p)))
4412 /* Historically, the compiler has treated a bare
4413 reference to a volatile lvalue as forcing a load. */
4414 tree tmp = create_tmp_var (TREE_TYPE (*expr_p), "vol");
4415 *expr_p = build (MODIFY_EXPR, TREE_TYPE (tmp), tmp, *expr_p);
4418 /* We can't do anything useful with a volatile reference to
4419 incomplete type, so just throw it away. */
4423 /* If we are gimplifying at the statement level, we're done. Tack
4424 everything together and replace the original statement with the
4426 if (fallback == fb_none || is_statement)
4428 if (internal_pre || internal_post)
4430 append_to_statement_list (*expr_p, &internal_pre);
4431 append_to_statement_list (internal_post, &internal_pre);
4432 annotate_all_with_locus (&internal_pre, input_location);
4433 *expr_p = internal_pre;
4437 else if (TREE_CODE (*expr_p) == STATEMENT_LIST)
4438 annotate_all_with_locus (expr_p, input_location);
4440 annotate_one_with_locus (*expr_p, input_location);
4444 /* Otherwise we're gimplifying a subexpression, so the resulting value is
4447 /* If it's sufficiently simple already, we're done. Unless we are
4448 handling some post-effects internally; if that's the case, we need to
4449 copy into a temp before adding the post-effects to the tree. */
4450 if (!internal_post && (*gimple_test_f) (*expr_p))
4453 /* Otherwise, we need to create a new temporary for the gimplified
4456 /* We can't return an lvalue if we have an internal postqueue. The
4457 object the lvalue refers to would (probably) be modified by the
4458 postqueue; we need to copy the value out first, which means an
4460 if ((fallback & fb_lvalue) && !internal_post
4461 && is_gimple_addressable (*expr_p))
4463 /* An lvalue will do. Take the address of the expression, store it
4464 in a temporary, and replace the expression with an INDIRECT_REF of
4466 tmp = build_fold_addr_expr (*expr_p);
4467 gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue);
4468 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp);
4470 else if ((fallback & fb_rvalue) && is_gimple_formal_tmp_rhs (*expr_p))
4472 gcc_assert (!VOID_TYPE_P (TREE_TYPE (*expr_p)));
4474 /* An rvalue will do. Assign the gimplified expression into a new
4475 temporary TMP and replace the original expression with TMP. */
4477 if (internal_post || (fallback & fb_lvalue))
4478 /* The postqueue might change the value of the expression between
4479 the initialization and use of the temporary, so we can't use a
4480 formal temp. FIXME do we care? */
4481 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
4483 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
4485 if (TREE_CODE (*expr_p) != SSA_NAME)
4486 DECL_GIMPLE_FORMAL_TEMP_P (*expr_p) = 1;
4490 #ifdef ENABLE_CHECKING
4491 if (!(fallback & fb_mayfail))
4493 fprintf (stderr, "gimplification failed:\n");
4494 print_generic_expr (stderr, *expr_p, 0);
4495 debug_tree (*expr_p);
4496 internal_error ("gimplification failed");
4499 gcc_assert (fallback & fb_mayfail);
4500 /* If this is an asm statement, and the user asked for the
4501 impossible, don't die. Fail and let gimplify_asm_expr
4507 /* Make sure the temporary matches our predicate. */
4508 gcc_assert ((*gimple_test_f) (*expr_p));
4512 annotate_all_with_locus (&internal_post, input_location);
4513 append_to_statement_list (internal_post, pre_p);
4517 input_location = saved_location;
4521 /* Look through TYPE for variable-sized objects and gimplify each such
4522 size that we find. Add to LIST_P any statements generated. */
4525 gimplify_type_sizes (tree type, tree *list_p)
4529 if (type == NULL || type == error_mark_node)
4532 /* We first do the main variant, then copy into any other variants. */
4533 type = TYPE_MAIN_VARIANT (type);
4535 /* Avoid infinite recursion. */
4536 if (TYPE_SIZES_GIMPLIFIED (type))
4539 TYPE_SIZES_GIMPLIFIED (type) = 1;
4541 switch (TREE_CODE (type))
4548 gimplify_one_sizepos (&TYPE_MIN_VALUE (type), list_p);
4549 gimplify_one_sizepos (&TYPE_MAX_VALUE (type), list_p);
4551 for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
4553 TYPE_MIN_VALUE (t) = TYPE_MIN_VALUE (type);
4554 TYPE_MAX_VALUE (t) = TYPE_MAX_VALUE (type);
4559 /* These types may not have declarations, so handle them here. */
4560 gimplify_type_sizes (TREE_TYPE (type), list_p);
4561 gimplify_type_sizes (TYPE_DOMAIN (type), list_p);
4566 case QUAL_UNION_TYPE:
4567 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4568 if (TREE_CODE (field) == FIELD_DECL)
4570 gimplify_one_sizepos (&DECL_FIELD_OFFSET (field), list_p);
4571 gimplify_type_sizes (TREE_TYPE (field), list_p);
4576 case REFERENCE_TYPE:
4577 gimplify_type_sizes (TREE_TYPE (type), list_p);
4584 gimplify_one_sizepos (&TYPE_SIZE (type), list_p);
4585 gimplify_one_sizepos (&TYPE_SIZE_UNIT (type), list_p);
4587 for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
4589 TYPE_SIZE (t) = TYPE_SIZE (type);
4590 TYPE_SIZE_UNIT (t) = TYPE_SIZE_UNIT (type);
4591 TYPE_SIZES_GIMPLIFIED (t) = 1;
4595 /* A subroutine of gimplify_type_sizes to make sure that *EXPR_P,
4596 a size or position, has had all of its SAVE_EXPRs evaluated.
4597 We add any required statements to STMT_P. */
4600 gimplify_one_sizepos (tree *expr_p, tree *stmt_p)
4602 /* We don't do anything if the value isn't there, is constant, or contains
4603 A PLACEHOLDER_EXPR. We also don't want to do anything if it's already
4604 a VAR_DECL. If it's a VAR_DECL from another function, the gimplifier
4605 will want to replace it with a new variable, but that will cause problems
4606 if this type is from outside the function. It's OK to have that here. */
4607 if (*expr_p == NULL_TREE || TREE_CONSTANT (*expr_p)
4608 || TREE_CODE (*expr_p) == VAR_DECL
4609 || CONTAINS_PLACEHOLDER_P (*expr_p))
4612 *expr_p = unshare_expr (*expr_p);
4613 gimplify_expr (expr_p, stmt_p, NULL, is_gimple_val, fb_rvalue);
4616 #ifdef ENABLE_CHECKING
4617 /* Compare types A and B for a "close enough" match. */
4620 cpt_same_type (tree a, tree b)
4622 if (lang_hooks.types_compatible_p (a, b))
4625 /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't
4626 link them together. This routine is intended to catch type errors
4627 that will affect the optimizers, and the optimizers don't add new
4628 dereferences of function pointers, so ignore it. */
4629 if ((TREE_CODE (a) == FUNCTION_TYPE || TREE_CODE (a) == METHOD_TYPE)
4630 && (TREE_CODE (b) == FUNCTION_TYPE || TREE_CODE (b) == METHOD_TYPE))
4633 /* ??? The C FE pushes type qualifiers after the fact into the type of
4634 the element from the type of the array. See build_unary_op's handling
4635 of ADDR_EXPR. This seems wrong -- if we were going to do this, we
4636 should have done it when creating the variable in the first place.
4637 Alternately, why aren't the two array types made variants? */
4638 if (TREE_CODE (a) == ARRAY_TYPE && TREE_CODE (b) == ARRAY_TYPE)
4639 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4641 /* And because of those, we have to recurse down through pointers. */
4642 if (POINTER_TYPE_P (a) && POINTER_TYPE_P (b))
4643 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
4648 /* Check for some cases of the front end missing cast expressions.
4649 The type of a dereference should correspond to the pointer type;
4650 similarly the type of an address should match its object. */
4653 check_pointer_types_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
4654 void *data ATTRIBUTE_UNUSED)
4657 tree ptype, otype, dtype;
4659 switch (TREE_CODE (t))
4663 otype = TREE_TYPE (t);
4664 ptype = TREE_TYPE (TREE_OPERAND (t, 0));
4665 dtype = TREE_TYPE (ptype);
4666 gcc_assert (cpt_same_type (otype, dtype));
4670 ptype = TREE_TYPE (t);
4671 otype = TREE_TYPE (TREE_OPERAND (t, 0));
4672 dtype = TREE_TYPE (ptype);
4673 if (!cpt_same_type (otype, dtype))
4675 /* &array is allowed to produce a pointer to the element, rather than
4676 a pointer to the array type. We must allow this in order to
4677 properly represent assigning the address of an array in C into
4678 pointer to the element type. */
4679 gcc_assert (TREE_CODE (otype) == ARRAY_TYPE
4680 && POINTER_TYPE_P (ptype)
4681 && cpt_same_type (TREE_TYPE (otype), dtype));
4695 /* Gimplify the body of statements pointed by BODY_P. FNDECL is the
4696 function decl containing BODY. */
4699 gimplify_body (tree *body_p, tree fndecl, bool do_parms)
4701 location_t saved_location = input_location;
4702 tree body, parm_stmts;
4704 timevar_push (TV_TREE_GIMPLIFY);
4705 push_gimplify_context ();
4707 /* Unshare most shared trees in the body and in that of any nested functions.
4708 It would seem we don't have to do this for nested functions because
4709 they are supposed to be output and then the outer function gimplified
4710 first, but the g++ front end doesn't always do it that way. */
4711 unshare_body (body_p, fndecl);
4712 unvisit_body (body_p, fndecl);
4714 /* Make sure input_location isn't set to something wierd. */
4715 input_location = DECL_SOURCE_LOCATION (fndecl);
4717 /* Resolve callee-copies. This has to be done before processing
4718 the body so that DECL_VALUE_EXPR gets processed correctly. */
4719 parm_stmts = do_parms ? gimplify_parameters () : NULL;
4721 /* Gimplify the function's body. */
4722 gimplify_stmt (body_p);
4726 body = alloc_stmt_list ();
4727 else if (TREE_CODE (body) == STATEMENT_LIST)
4729 tree t = expr_only (*body_p);
4734 /* If there isn't an outer BIND_EXPR, add one. */
4735 if (TREE_CODE (body) != BIND_EXPR)
4737 tree b = build (BIND_EXPR, void_type_node, NULL_TREE,
4738 NULL_TREE, NULL_TREE);
4739 TREE_SIDE_EFFECTS (b) = 1;
4740 append_to_statement_list_force (body, &BIND_EXPR_BODY (b));
4744 /* If we had callee-copies statements, insert them at the beginning
4748 append_to_statement_list_force (BIND_EXPR_BODY (body), &parm_stmts);
4749 BIND_EXPR_BODY (body) = parm_stmts;
4752 /* Unshare again, in case gimplification was sloppy. */
4753 unshare_all_trees (body);
4757 pop_gimplify_context (body);
4759 #ifdef ENABLE_CHECKING
4760 walk_tree (body_p, check_pointer_types_r, NULL, NULL);
4763 timevar_pop (TV_TREE_GIMPLIFY);
4764 input_location = saved_location;
4767 /* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL
4768 node for the function we want to gimplify. */
4771 gimplify_function_tree (tree fndecl)
4773 tree oldfn, parm, ret;
4775 oldfn = current_function_decl;
4776 current_function_decl = fndecl;
4777 cfun = DECL_STRUCT_FUNCTION (fndecl);
4779 allocate_struct_function (fndecl);
4781 for (parm = DECL_ARGUMENTS (fndecl); parm ; parm = TREE_CHAIN (parm))
4783 /* Preliminarily mark non-addressed complex variables as eligible
4784 for promotion to gimple registers. We'll transform their uses
4786 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
4787 && !TREE_THIS_VOLATILE (parm)
4788 && !needs_to_live_in_memory (parm))
4789 DECL_COMPLEX_GIMPLE_REG_P (parm) = 1;
4792 ret = DECL_RESULT (fndecl);
4793 if (TREE_CODE (TREE_TYPE (ret)) == COMPLEX_TYPE
4794 && !needs_to_live_in_memory (ret))
4795 DECL_COMPLEX_GIMPLE_REG_P (ret) = 1;
4797 gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl, true);
4799 /* If we're instrumenting function entry/exit, then prepend the call to
4800 the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
4801 catch the exit hook. */
4802 /* ??? Add some way to ignore exceptions for this TFE. */
4803 if (flag_instrument_function_entry_exit
4804 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl))
4808 tf = build (TRY_FINALLY_EXPR, void_type_node, NULL, NULL);
4809 TREE_SIDE_EFFECTS (tf) = 1;
4810 x = DECL_SAVED_TREE (fndecl);
4811 append_to_statement_list (x, &TREE_OPERAND (tf, 0));
4812 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_EXIT];
4813 x = build_function_call_expr (x, NULL);
4814 append_to_statement_list (x, &TREE_OPERAND (tf, 1));
4816 bind = build (BIND_EXPR, void_type_node, NULL, NULL, NULL);
4817 TREE_SIDE_EFFECTS (bind) = 1;
4818 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_ENTER];
4819 x = build_function_call_expr (x, NULL);
4820 append_to_statement_list (x, &BIND_EXPR_BODY (bind));
4821 append_to_statement_list (tf, &BIND_EXPR_BODY (bind));
4823 DECL_SAVED_TREE (fndecl) = bind;
4826 current_function_decl = oldfn;
4827 cfun = oldfn ? DECL_STRUCT_FUNCTION (oldfn) : NULL;
4831 /* Expands EXPR to list of gimple statements STMTS. If SIMPLE is true,
4832 force the result to be either ssa_name or an invariant, otherwise
4833 just force it to be a rhs expression. If VAR is not NULL, make the
4834 base variable of the final destination be VAR if suitable. */
4837 force_gimple_operand (tree expr, tree *stmts, bool simple, tree var)
4840 enum gimplify_status ret;
4841 gimple_predicate gimple_test_f;
4845 if (is_gimple_val (expr))
4848 gimple_test_f = simple ? is_gimple_val : is_gimple_reg_rhs;
4850 push_gimplify_context ();
4851 gimplify_ctxp->into_ssa = in_ssa_p;
4854 expr = build (MODIFY_EXPR, TREE_TYPE (var), var, expr);
4856 ret = gimplify_expr (&expr, stmts, NULL,
4857 gimple_test_f, fb_rvalue);
4858 gcc_assert (ret != GS_ERROR);
4860 if (referenced_vars)
4862 for (t = gimplify_ctxp->temps; t ; t = TREE_CHAIN (t))
4863 add_referenced_tmp_var (t);
4866 pop_gimplify_context (NULL);
4871 /* Invokes force_gimple_operand for EXPR with parameters SIMPLE_P and VAR. If
4872 some statements are produced, emits them before BSI. */
4875 force_gimple_operand_bsi (block_stmt_iterator *bsi, tree expr,
4876 bool simple_p, tree var)
4880 expr = force_gimple_operand (expr, &stmts, simple_p, var);
4882 bsi_insert_before (bsi, stmts, BSI_SAME_STMT);
4887 #include "gt-gimplify.h"