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 to 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 /* Subroutine for find_single_pointer_decl. */
304 find_single_pointer_decl_1 (tree
*tp
, int *walk_subtrees ATTRIBUTE_UNUSED
,
307 tree
*pdecl
= (tree
*) data
;
309 if (DECL_P (*tp
) && POINTER_TYPE_P (TREE_TYPE (*tp
)))
313 /* We already found a pointer decl; return anything other
314 than NULL_TREE to unwind from walk_tree signalling that
315 we have a duplicate. */
324 /* Find the single DECL of pointer type in the tree T and return it.
325 If there are zero or more than one such DECLs, return NULL. */
328 find_single_pointer_decl (tree t
)
330 tree decl
= NULL_TREE
;
332 if (walk_tree (&t
, find_single_pointer_decl_1
, &decl
, NULL
))
334 /* find_single_pointer_decl_1 returns a non-zero value, causing
335 walk_tree to return a non-zero value, to indicate that it
336 found more than one pointer DECL. */
343 /* Create a new temporary name with PREFIX. Returns an identifier. */
345 static GTY(()) unsigned int tmp_var_id_num
;
348 create_tmp_var_name (const char *prefix
)
354 char *preftmp
= ASTRDUP (prefix
);
356 remove_suffix (preftmp
, strlen (preftmp
));
360 ASM_FORMAT_PRIVATE_NAME (tmp_name
, prefix
? prefix
: "T", tmp_var_id_num
++);
361 return get_identifier (tmp_name
);
365 /* Create a new temporary variable declaration of type TYPE.
366 Does NOT push it into the current binding. */
369 create_tmp_var_raw (tree type
, const char *prefix
)
374 /* Make the type of the variable writable. */
375 new_type
= build_type_variant (type
, 0, 0);
376 TYPE_ATTRIBUTES (new_type
) = TYPE_ATTRIBUTES (type
);
378 tmp_var
= build_decl (VAR_DECL
, prefix
? create_tmp_var_name (prefix
) : NULL
,
381 /* The variable was declared by the compiler. */
382 DECL_ARTIFICIAL (tmp_var
) = 1;
383 /* And we don't want debug info for it. */
384 DECL_IGNORED_P (tmp_var
) = 1;
386 /* Make the variable writable. */
387 TREE_READONLY (tmp_var
) = 0;
389 DECL_EXTERNAL (tmp_var
) = 0;
390 TREE_STATIC (tmp_var
) = 0;
391 TREE_USED (tmp_var
) = 1;
396 /* Create a new temporary variable declaration of type TYPE. DOES push the
397 variable into the current binding. Further, assume that this is called
398 only from gimplification or optimization, at which point the creation of
399 certain types are bugs. */
402 create_tmp_var (tree type
, const char *prefix
)
406 /* We don't allow types that are addressable (meaning we can't make copies),
407 incomplete, or of variable size. */
408 gcc_assert (!TREE_ADDRESSABLE (type
)
409 && COMPLETE_TYPE_P (type
)
410 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
);
412 tmp_var
= create_tmp_var_raw (type
, prefix
);
413 gimple_add_tmp_var (tmp_var
);
417 /* Given a tree, try to return a useful variable name that we can use
418 to prefix a temporary that is being assigned the value of the tree.
419 I.E. given <temp> = &A, return A. */
427 STRIP_NOPS (stripped_decl
);
428 if (DECL_P (stripped_decl
) && DECL_NAME (stripped_decl
))
429 return IDENTIFIER_POINTER (DECL_NAME (stripped_decl
));
432 switch (TREE_CODE (stripped_decl
))
435 return get_name (TREE_OPERAND (stripped_decl
, 0));
443 /* Create a temporary with a name derived from VAL. Subroutine of
444 lookup_tmp_var; nobody else should call this function. */
447 create_tmp_from_val (tree val
)
449 return create_tmp_var (TYPE_MAIN_VARIANT (TREE_TYPE (val
)), get_name (val
));
452 /* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse
453 an existing expression temporary. */
456 lookup_tmp_var (tree val
, bool is_formal
)
460 /* If not optimizing, never really reuse a temporary. local-alloc
461 won't allocate any variable that is used in more than one basic
462 block, which means it will go into memory, causing much extra
463 work in reload and final and poorer code generation, outweighing
464 the extra memory allocation here. */
465 if (!optimize
|| !is_formal
|| TREE_SIDE_EFFECTS (val
))
466 ret
= create_tmp_from_val (val
);
473 slot
= htab_find_slot (gimplify_ctxp
->temp_htab
, (void *)&elt
, INSERT
);
476 elt_p
= xmalloc (sizeof (*elt_p
));
478 elt_p
->temp
= ret
= create_tmp_from_val (val
);
479 *slot
= (void *) elt_p
;
483 elt_p
= (elt_t
*) *slot
;
489 DECL_GIMPLE_FORMAL_TEMP_P (ret
) = 1;
494 /* Returns a formal temporary variable initialized with VAL. PRE_P is as
495 in gimplify_expr. Only use this function if:
497 1) The value of the unfactored expression represented by VAL will not
498 change between the initialization and use of the temporary, and
499 2) The temporary will not be otherwise modified.
501 For instance, #1 means that this is inappropriate for SAVE_EXPR temps,
502 and #2 means it is inappropriate for && temps.
504 For other cases, use get_initialized_tmp_var instead. */
507 internal_get_tmp_var (tree val
, tree
*pre_p
, tree
*post_p
, bool is_formal
)
511 gimplify_expr (&val
, pre_p
, post_p
, is_gimple_formal_tmp_rhs
, fb_rvalue
);
513 t
= lookup_tmp_var (val
, is_formal
);
517 tree u
= find_single_pointer_decl (val
);
519 if (u
&& TREE_CODE (u
) == VAR_DECL
&& DECL_BASED_ON_RESTRICT_P (u
))
520 u
= DECL_GET_RESTRICT_BASE (u
);
521 if (u
&& TYPE_RESTRICT (TREE_TYPE (u
)))
523 if (DECL_BASED_ON_RESTRICT_P (t
))
524 gcc_assert (u
== DECL_GET_RESTRICT_BASE (t
));
527 DECL_BASED_ON_RESTRICT_P (t
) = 1;
528 SET_DECL_RESTRICT_BASE (t
, u
);
533 if (TREE_CODE (TREE_TYPE (t
)) == COMPLEX_TYPE
)
534 DECL_COMPLEX_GIMPLE_REG_P (t
) = 1;
536 mod
= build (MODIFY_EXPR
, TREE_TYPE (t
), t
, val
);
538 if (EXPR_HAS_LOCATION (val
))
539 SET_EXPR_LOCUS (mod
, EXPR_LOCUS (val
));
541 SET_EXPR_LOCATION (mod
, input_location
);
543 /* gimplify_modify_expr might want to reduce this further. */
544 gimplify_and_add (mod
, pre_p
);
546 /* If we're gimplifying into ssa, gimplify_modify_expr will have
547 given our temporary an ssa name. Find and return it. */
548 if (gimplify_ctxp
->into_ssa
)
549 t
= TREE_OPERAND (mod
, 0);
555 get_formal_tmp_var (tree val
, tree
*pre_p
)
557 return internal_get_tmp_var (val
, pre_p
, NULL
, true);
560 /* Returns a temporary variable initialized with VAL. PRE_P and POST_P
561 are as in gimplify_expr. */
564 get_initialized_tmp_var (tree val
, tree
*pre_p
, tree
*post_p
)
566 return internal_get_tmp_var (val
, pre_p
, post_p
, false);
569 /* Declares all the variables in VARS in SCOPE. */
572 declare_tmp_vars (tree vars
, tree scope
)
579 /* C99 mode puts the default 'return 0;' for main outside the outer
580 braces. So drill down until we find an actual scope. */
581 while (TREE_CODE (scope
) == COMPOUND_EXPR
)
582 scope
= TREE_OPERAND (scope
, 0);
584 gcc_assert (TREE_CODE (scope
) == BIND_EXPR
);
586 temps
= nreverse (last
);
587 TREE_CHAIN (last
) = BIND_EXPR_VARS (scope
);
588 BIND_EXPR_VARS (scope
) = temps
;
593 gimple_add_tmp_var (tree tmp
)
595 gcc_assert (!TREE_CHAIN (tmp
) && !DECL_SEEN_IN_BIND_EXPR_P (tmp
));
597 DECL_CONTEXT (tmp
) = current_function_decl
;
598 DECL_SEEN_IN_BIND_EXPR_P (tmp
) = 1;
602 TREE_CHAIN (tmp
) = gimplify_ctxp
->temps
;
603 gimplify_ctxp
->temps
= tmp
;
608 declare_tmp_vars (tmp
, DECL_SAVED_TREE (current_function_decl
));
611 /* Determines whether to assign a locus to the statement STMT. */
614 should_carry_locus_p (tree stmt
)
616 /* Don't emit a line note for a label. We particularly don't want to
617 emit one for the break label, since it doesn't actually correspond
618 to the beginning of the loop/switch. */
619 if (TREE_CODE (stmt
) == LABEL_EXPR
)
622 /* Do not annotate empty statements, since it confuses gcov. */
623 if (!TREE_SIDE_EFFECTS (stmt
))
630 annotate_one_with_locus (tree t
, location_t locus
)
632 if (EXPR_P (t
) && ! EXPR_HAS_LOCATION (t
) && should_carry_locus_p (t
))
633 SET_EXPR_LOCATION (t
, locus
);
637 annotate_all_with_locus (tree
*stmt_p
, location_t locus
)
639 tree_stmt_iterator i
;
644 for (i
= tsi_start (*stmt_p
); !tsi_end_p (i
); tsi_next (&i
))
646 tree t
= tsi_stmt (i
);
648 /* Assuming we've already been gimplified, we shouldn't
649 see nested chaining constructs anymore. */
650 gcc_assert (TREE_CODE (t
) != STATEMENT_LIST
651 && TREE_CODE (t
) != COMPOUND_EXPR
);
653 annotate_one_with_locus (t
, locus
);
657 /* Similar to copy_tree_r() but do not copy SAVE_EXPR or TARGET_EXPR nodes.
658 These nodes model computations that should only be done once. If we
659 were to unshare something like SAVE_EXPR(i++), the gimplification
660 process would create wrong code. */
663 mostly_copy_tree_r (tree
*tp
, int *walk_subtrees
, void *data
)
665 enum tree_code code
= TREE_CODE (*tp
);
666 /* Don't unshare types, decls, constants and SAVE_EXPR nodes. */
667 if (TREE_CODE_CLASS (code
) == tcc_type
668 || TREE_CODE_CLASS (code
) == tcc_declaration
669 || TREE_CODE_CLASS (code
) == tcc_constant
670 || code
== SAVE_EXPR
|| code
== TARGET_EXPR
671 /* We can't do anything sensible with a BLOCK used as an expression,
672 but we also can't just die when we see it because of non-expression
673 uses. So just avert our eyes and cross our fingers. Silly Java. */
678 gcc_assert (code
!= BIND_EXPR
);
679 copy_tree_r (tp
, walk_subtrees
, data
);
685 /* Callback for walk_tree to unshare most of the shared trees rooted at
686 *TP. If *TP has been visited already (i.e., TREE_VISITED (*TP) == 1),
687 then *TP is deep copied by calling copy_tree_r.
689 This unshares the same trees as copy_tree_r with the exception of
690 SAVE_EXPR nodes. These nodes model computations that should only be
691 done once. If we were to unshare something like SAVE_EXPR(i++), the
692 gimplification process would create wrong code. */
695 copy_if_shared_r (tree
*tp
, int *walk_subtrees ATTRIBUTE_UNUSED
,
696 void *data ATTRIBUTE_UNUSED
)
699 enum tree_code code
= TREE_CODE (t
);
701 /* Skip types, decls, and constants. But we do want to look at their
702 types and the bounds of types. Mark them as visited so we properly
703 unmark their subtrees on the unmark pass. If we've already seen them,
704 don't look down further. */
705 if (TREE_CODE_CLASS (code
) == tcc_type
706 || TREE_CODE_CLASS (code
) == tcc_declaration
707 || TREE_CODE_CLASS (code
) == tcc_constant
)
709 if (TREE_VISITED (t
))
712 TREE_VISITED (t
) = 1;
715 /* If this node has been visited already, unshare it and don't look
717 else if (TREE_VISITED (t
))
719 walk_tree (tp
, mostly_copy_tree_r
, NULL
, NULL
);
723 /* Otherwise, mark the tree as visited and keep looking. */
725 TREE_VISITED (t
) = 1;
731 unmark_visited_r (tree
*tp
, int *walk_subtrees ATTRIBUTE_UNUSED
,
732 void *data ATTRIBUTE_UNUSED
)
734 if (TREE_VISITED (*tp
))
735 TREE_VISITED (*tp
) = 0;
742 /* Unshare all the trees in BODY_P, a pointer into the body of FNDECL, and the
743 bodies of any nested functions if we are unsharing the entire body of
747 unshare_body (tree
*body_p
, tree fndecl
)
749 struct cgraph_node
*cgn
= cgraph_node (fndecl
);
751 walk_tree (body_p
, copy_if_shared_r
, NULL
, NULL
);
752 if (body_p
== &DECL_SAVED_TREE (fndecl
))
753 for (cgn
= cgn
->nested
; cgn
; cgn
= cgn
->next_nested
)
754 unshare_body (&DECL_SAVED_TREE (cgn
->decl
), cgn
->decl
);
757 /* Likewise, but mark all trees as not visited. */
760 unvisit_body (tree
*body_p
, tree fndecl
)
762 struct cgraph_node
*cgn
= cgraph_node (fndecl
);
764 walk_tree (body_p
, unmark_visited_r
, NULL
, NULL
);
765 if (body_p
== &DECL_SAVED_TREE (fndecl
))
766 for (cgn
= cgn
->nested
; cgn
; cgn
= cgn
->next_nested
)
767 unvisit_body (&DECL_SAVED_TREE (cgn
->decl
), cgn
->decl
);
770 /* Unshare T and all the trees reached from T via TREE_CHAIN. */
773 unshare_all_trees (tree t
)
775 walk_tree (&t
, copy_if_shared_r
, NULL
, NULL
);
776 walk_tree (&t
, unmark_visited_r
, NULL
, NULL
);
779 /* Unconditionally make an unshared copy of EXPR. This is used when using
780 stored expressions which span multiple functions, such as BINFO_VTABLE,
781 as the normal unsharing process can't tell that they're shared. */
784 unshare_expr (tree expr
)
786 walk_tree (&expr
, mostly_copy_tree_r
, NULL
, NULL
);
790 /* A terser interface for building a representation of an exception
794 gimple_build_eh_filter (tree body
, tree allowed
, tree failure
)
798 /* FIXME should the allowed types go in TREE_TYPE? */
799 t
= build (EH_FILTER_EXPR
, void_type_node
, allowed
, NULL_TREE
);
800 append_to_statement_list (failure
, &EH_FILTER_FAILURE (t
));
802 t
= build (TRY_CATCH_EXPR
, void_type_node
, NULL_TREE
, t
);
803 append_to_statement_list (body
, &TREE_OPERAND (t
, 0));
809 /* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
810 contain statements and have a value. Assign its value to a temporary
811 and give it void_type_node. Returns the temporary, or NULL_TREE if
812 WRAPPER was already void. */
815 voidify_wrapper_expr (tree wrapper
, tree temp
)
817 if (!VOID_TYPE_P (TREE_TYPE (wrapper
)))
819 tree
*p
, sub
= wrapper
;
822 /* Set p to point to the body of the wrapper. */
823 switch (TREE_CODE (sub
))
826 /* For a BIND_EXPR, the body is operand 1. */
827 p
= &BIND_EXPR_BODY (sub
);
831 p
= &TREE_OPERAND (sub
, 0);
835 /* Advance to the last statement. Set all container types to void. */
836 if (TREE_CODE (*p
) == STATEMENT_LIST
)
838 tree_stmt_iterator i
= tsi_last (*p
);
839 p
= tsi_end_p (i
) ? NULL
: tsi_stmt_ptr (i
);
843 for (; TREE_CODE (*p
) == COMPOUND_EXPR
; p
= &TREE_OPERAND (*p
, 1))
845 TREE_SIDE_EFFECTS (*p
) = 1;
846 TREE_TYPE (*p
) = void_type_node
;
850 if (p
== NULL
|| IS_EMPTY_STMT (*p
))
852 /* Look through exception handling. */
853 else if (TREE_CODE (*p
) == TRY_FINALLY_EXPR
854 || TREE_CODE (*p
) == TRY_CATCH_EXPR
)
859 /* The C++ frontend already did this for us. */
860 else if (TREE_CODE (*p
) == INIT_EXPR
861 || TREE_CODE (*p
) == TARGET_EXPR
)
862 temp
= TREE_OPERAND (*p
, 0);
863 /* If we're returning a dereference, move the dereference
864 outside the wrapper. */
865 else if (TREE_CODE (*p
) == INDIRECT_REF
)
867 tree ptr
= TREE_OPERAND (*p
, 0);
868 temp
= create_tmp_var (TREE_TYPE (ptr
), "retval");
869 *p
= build (MODIFY_EXPR
, TREE_TYPE (ptr
), temp
, ptr
);
870 temp
= build1 (INDIRECT_REF
, TREE_TYPE (TREE_TYPE (temp
)), temp
);
871 /* If this is a BIND_EXPR for a const inline function, it might not
872 have TREE_SIDE_EFFECTS set. That is no longer accurate. */
873 TREE_SIDE_EFFECTS (wrapper
) = 1;
878 temp
= create_tmp_var (TREE_TYPE (wrapper
), "retval");
879 *p
= build (MODIFY_EXPR
, TREE_TYPE (temp
), temp
, *p
);
880 TREE_SIDE_EFFECTS (wrapper
) = 1;
883 TREE_TYPE (wrapper
) = void_type_node
;
890 /* Prepare calls to builtins to SAVE and RESTORE the stack as well as
891 a temporary through which they communicate. */
894 build_stack_save_restore (tree
*save
, tree
*restore
)
896 tree save_call
, tmp_var
;
899 build_function_call_expr (implicit_built_in_decls
[BUILT_IN_STACK_SAVE
],
901 tmp_var
= create_tmp_var (ptr_type_node
, "saved_stack");
903 *save
= build (MODIFY_EXPR
, ptr_type_node
, tmp_var
, save_call
);
905 build_function_call_expr (implicit_built_in_decls
[BUILT_IN_STACK_RESTORE
],
906 tree_cons (NULL_TREE
, tmp_var
, NULL_TREE
));
909 /* Gimplify a BIND_EXPR. Just voidify and recurse. */
911 static enum gimplify_status
912 gimplify_bind_expr (tree
*expr_p
, tree temp
, tree
*pre_p
)
914 tree bind_expr
= *expr_p
;
915 bool old_save_stack
= gimplify_ctxp
->save_stack
;
918 temp
= voidify_wrapper_expr (bind_expr
, temp
);
920 /* Mark variables seen in this bind expr. */
921 for (t
= BIND_EXPR_VARS (bind_expr
); t
; t
= TREE_CHAIN (t
))
923 if (TREE_CODE (t
) == VAR_DECL
)
924 DECL_SEEN_IN_BIND_EXPR_P (t
) = 1;
926 /* Preliminarily mark non-addressed complex variables as eligible
927 for promotion to gimple registers. We'll transform their uses
929 if (TREE_CODE (TREE_TYPE (t
)) == COMPLEX_TYPE
930 && !TREE_THIS_VOLATILE (t
)
931 && (TREE_CODE (t
) == VAR_DECL
&& !DECL_HARD_REGISTER (t
))
932 && !needs_to_live_in_memory (t
))
933 DECL_COMPLEX_GIMPLE_REG_P (t
) = 1;
936 gimple_push_bind_expr (bind_expr
);
937 gimplify_ctxp
->save_stack
= false;
939 gimplify_to_stmt_list (&BIND_EXPR_BODY (bind_expr
));
941 if (gimplify_ctxp
->save_stack
)
943 tree stack_save
, stack_restore
;
945 /* Save stack on entry and restore it on exit. Add a try_finally
946 block to achieve this. Note that mudflap depends on the
947 format of the emitted code: see mx_register_decls(). */
948 build_stack_save_restore (&stack_save
, &stack_restore
);
950 t
= build (TRY_FINALLY_EXPR
, void_type_node
,
951 BIND_EXPR_BODY (bind_expr
), NULL_TREE
);
952 append_to_statement_list (stack_restore
, &TREE_OPERAND (t
, 1));
954 BIND_EXPR_BODY (bind_expr
) = NULL_TREE
;
955 append_to_statement_list (stack_save
, &BIND_EXPR_BODY (bind_expr
));
956 append_to_statement_list (t
, &BIND_EXPR_BODY (bind_expr
));
959 gimplify_ctxp
->save_stack
= old_save_stack
;
960 gimple_pop_bind_expr ();
965 append_to_statement_list (bind_expr
, pre_p
);
972 /* Gimplify a RETURN_EXPR. If the expression to be returned is not a
973 GIMPLE value, it is assigned to a new temporary and the statement is
974 re-written to return the temporary.
976 PRE_P points to the list where side effects that must happen before
977 STMT should be stored. */
979 static enum gimplify_status
980 gimplify_return_expr (tree stmt
, tree
*pre_p
)
982 tree ret_expr
= TREE_OPERAND (stmt
, 0);
983 tree result_decl
, result
;
985 if (!ret_expr
|| TREE_CODE (ret_expr
) == RESULT_DECL
986 || ret_expr
== error_mark_node
)
989 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl
))))
990 result_decl
= NULL_TREE
;
993 result_decl
= TREE_OPERAND (ret_expr
, 0);
994 if (TREE_CODE (result_decl
) == INDIRECT_REF
)
995 /* See through a return by reference. */
996 result_decl
= TREE_OPERAND (result_decl
, 0);
998 gcc_assert ((TREE_CODE (ret_expr
) == MODIFY_EXPR
999 || TREE_CODE (ret_expr
) == INIT_EXPR
)
1000 && TREE_CODE (result_decl
) == RESULT_DECL
);
1003 /* If aggregate_value_p is true, then we can return the bare RESULT_DECL.
1004 Recall that aggregate_value_p is FALSE for any aggregate type that is
1005 returned in registers. If we're returning values in registers, then
1006 we don't want to extend the lifetime of the RESULT_DECL, particularly
1007 across another call. In addition, for those aggregates for which
1008 hard_function_value generates a PARALLEL, we'll die during normal
1009 expansion of structure assignments; there's special code in expand_return
1010 to handle this case that does not exist in expand_expr. */
1012 || aggregate_value_p (result_decl
, TREE_TYPE (current_function_decl
)))
1013 result
= result_decl
;
1014 else if (gimplify_ctxp
->return_temp
)
1015 result
= gimplify_ctxp
->return_temp
;
1018 result
= create_tmp_var (TREE_TYPE (result_decl
), NULL
);
1020 /* ??? With complex control flow (usually involving abnormal edges),
1021 we can wind up warning about an uninitialized value for this. Due
1022 to how this variable is constructed and initialized, this is never
1023 true. Give up and never warn. */
1024 TREE_NO_WARNING (result
) = 1;
1026 gimplify_ctxp
->return_temp
= result
;
1029 /* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
1030 Then gimplify the whole thing. */
1031 if (result
!= result_decl
)
1032 TREE_OPERAND (ret_expr
, 0) = result
;
1034 gimplify_and_add (TREE_OPERAND (stmt
, 0), pre_p
);
1036 /* If we didn't use a temporary, then the result is just the result_decl.
1037 Otherwise we need a simple copy. This should already be gimple. */
1038 if (result
== result_decl
)
1041 ret_expr
= build (MODIFY_EXPR
, TREE_TYPE (result
), result_decl
, result
);
1042 TREE_OPERAND (stmt
, 0) = ret_expr
;
1047 /* Gimplifies a DECL_EXPR node *STMT_P by making any necessary allocation
1048 and initialization explicit. */
1050 static enum gimplify_status
1051 gimplify_decl_expr (tree
*stmt_p
)
1053 tree stmt
= *stmt_p
;
1054 tree decl
= DECL_EXPR_DECL (stmt
);
1056 *stmt_p
= NULL_TREE
;
1058 if (TREE_TYPE (decl
) == error_mark_node
)
1061 if ((TREE_CODE (decl
) == TYPE_DECL
1062 || TREE_CODE (decl
) == VAR_DECL
)
1063 && !TYPE_SIZES_GIMPLIFIED (TREE_TYPE (decl
)))
1064 gimplify_type_sizes (TREE_TYPE (decl
), stmt_p
);
1066 if (TREE_CODE (decl
) == VAR_DECL
&& !DECL_EXTERNAL (decl
))
1068 tree init
= DECL_INITIAL (decl
);
1070 if (!TREE_CONSTANT (DECL_SIZE (decl
)))
1072 /* This is a variable-sized decl. Simplify its size and mark it
1073 for deferred expansion. Note that mudflap depends on the format
1074 of the emitted code: see mx_register_decls(). */
1075 tree t
, args
, addr
, ptr_type
;
1077 gimplify_one_sizepos (&DECL_SIZE (decl
), stmt_p
);
1078 gimplify_one_sizepos (&DECL_SIZE_UNIT (decl
), stmt_p
);
1080 /* All occurrences of this decl in final gimplified code will be
1081 replaced by indirection. Setting DECL_VALUE_EXPR does two
1082 things: First, it lets the rest of the gimplifier know what
1083 replacement to use. Second, it lets the debug info know
1084 where to find the value. */
1085 ptr_type
= build_pointer_type (TREE_TYPE (decl
));
1086 addr
= create_tmp_var (ptr_type
, get_name (decl
));
1087 DECL_IGNORED_P (addr
) = 0;
1088 t
= build_fold_indirect_ref (addr
);
1089 SET_DECL_VALUE_EXPR (decl
, t
);
1090 DECL_HAS_VALUE_EXPR_P (decl
) = 1;
1092 args
= tree_cons (NULL
, DECL_SIZE_UNIT (decl
), NULL
);
1093 t
= built_in_decls
[BUILT_IN_ALLOCA
];
1094 t
= build_function_call_expr (t
, args
);
1095 t
= fold_convert (ptr_type
, t
);
1096 t
= build2 (MODIFY_EXPR
, void_type_node
, addr
, t
);
1098 gimplify_and_add (t
, stmt_p
);
1100 /* Indicate that we need to restore the stack level when the
1101 enclosing BIND_EXPR is exited. */
1102 gimplify_ctxp
->save_stack
= true;
1105 if (init
&& init
!= error_mark_node
)
1107 if (!TREE_STATIC (decl
))
1109 DECL_INITIAL (decl
) = NULL_TREE
;
1110 init
= build (MODIFY_EXPR
, void_type_node
, decl
, init
);
1111 gimplify_and_add (init
, stmt_p
);
1114 /* We must still examine initializers for static variables
1115 as they may contain a label address. */
1116 walk_tree (&init
, force_labels_r
, NULL
, NULL
);
1119 /* This decl isn't mentioned in the enclosing block, so add it to the
1120 list of temps. FIXME it seems a bit of a kludge to say that
1121 anonymous artificial vars aren't pushed, but everything else is. */
1122 if (DECL_ARTIFICIAL (decl
) && DECL_NAME (decl
) == NULL_TREE
)
1123 gimple_add_tmp_var (decl
);
1129 /* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body
1130 and replacing the LOOP_EXPR with goto, but if the loop contains an
1131 EXIT_EXPR, we need to append a label for it to jump to. */
1133 static enum gimplify_status
1134 gimplify_loop_expr (tree
*expr_p
, tree
*pre_p
)
1136 tree saved_label
= gimplify_ctxp
->exit_label
;
1137 tree start_label
= build1 (LABEL_EXPR
, void_type_node
, NULL_TREE
);
1138 tree jump_stmt
= build_and_jump (&LABEL_EXPR_LABEL (start_label
));
1140 append_to_statement_list (start_label
, pre_p
);
1142 gimplify_ctxp
->exit_label
= NULL_TREE
;
1144 gimplify_and_add (LOOP_EXPR_BODY (*expr_p
), pre_p
);
1146 if (gimplify_ctxp
->exit_label
)
1148 append_to_statement_list (jump_stmt
, pre_p
);
1149 *expr_p
= build1 (LABEL_EXPR
, void_type_node
, gimplify_ctxp
->exit_label
);
1152 *expr_p
= jump_stmt
;
1154 gimplify_ctxp
->exit_label
= saved_label
;
1159 /* Compare two case labels. Because the front end should already have
1160 made sure that case ranges do not overlap, it is enough to only compare
1161 the CASE_LOW values of each case label. */
1164 compare_case_labels (const void *p1
, const void *p2
)
1166 tree case1
= *(tree
*)p1
;
1167 tree case2
= *(tree
*)p2
;
1169 return tree_int_cst_compare (CASE_LOW (case1
), CASE_LOW (case2
));
1172 /* Sort the case labels in LABEL_VEC in place in ascending order. */
1175 sort_case_labels (tree label_vec
)
1177 size_t len
= TREE_VEC_LENGTH (label_vec
);
1178 tree default_case
= TREE_VEC_ELT (label_vec
, len
- 1);
1180 if (CASE_LOW (default_case
))
1184 /* The last label in the vector should be the default case
1186 for (i
= 0; i
< len
; ++i
)
1188 tree t
= TREE_VEC_ELT (label_vec
, i
);
1192 TREE_VEC_ELT (label_vec
, i
) = TREE_VEC_ELT (label_vec
, len
- 1);
1193 TREE_VEC_ELT (label_vec
, len
- 1) = default_case
;
1199 qsort (&TREE_VEC_ELT (label_vec
, 0), len
- 1, sizeof (tree
),
1200 compare_case_labels
);
1203 /* Gimplify a SWITCH_EXPR, and collect a TREE_VEC of the labels it can
1206 static enum gimplify_status
1207 gimplify_switch_expr (tree
*expr_p
, tree
*pre_p
)
1209 tree switch_expr
= *expr_p
;
1210 enum gimplify_status ret
;
1212 ret
= gimplify_expr (&SWITCH_COND (switch_expr
), pre_p
, NULL
,
1213 is_gimple_val
, fb_rvalue
);
1215 if (SWITCH_BODY (switch_expr
))
1217 VEC(tree
,heap
) *labels
, *saved_labels
;
1218 tree label_vec
, default_case
= NULL_TREE
;
1221 /* If someone can be bothered to fill in the labels, they can
1222 be bothered to null out the body too. */
1223 gcc_assert (!SWITCH_LABELS (switch_expr
));
1225 saved_labels
= gimplify_ctxp
->case_labels
;
1226 gimplify_ctxp
->case_labels
= VEC_alloc (tree
, heap
, 8);
1228 gimplify_to_stmt_list (&SWITCH_BODY (switch_expr
));
1230 labels
= gimplify_ctxp
->case_labels
;
1231 gimplify_ctxp
->case_labels
= saved_labels
;
1233 len
= VEC_length (tree
, labels
);
1235 for (i
= 0; i
< len
; ++i
)
1237 tree t
= VEC_index (tree
, labels
, i
);
1240 /* The default case must be the last label in the list. */
1242 VEC_replace (tree
, labels
, i
, VEC_index (tree
, labels
, len
- 1));
1248 label_vec
= make_tree_vec (len
+ 1);
1249 SWITCH_LABELS (*expr_p
) = label_vec
;
1250 append_to_statement_list (switch_expr
, pre_p
);
1254 /* If the switch has no default label, add one, so that we jump
1255 around the switch body. */
1256 default_case
= build (CASE_LABEL_EXPR
, void_type_node
, NULL_TREE
,
1257 NULL_TREE
, create_artificial_label ());
1258 append_to_statement_list (SWITCH_BODY (switch_expr
), pre_p
);
1259 *expr_p
= build (LABEL_EXPR
, void_type_node
,
1260 CASE_LABEL (default_case
));
1263 *expr_p
= SWITCH_BODY (switch_expr
);
1265 for (i
= 0; i
< len
; ++i
)
1266 TREE_VEC_ELT (label_vec
, i
) = VEC_index (tree
, labels
, i
);
1267 TREE_VEC_ELT (label_vec
, len
) = default_case
;
1269 VEC_free (tree
, heap
, labels
);
1271 sort_case_labels (label_vec
);
1273 SWITCH_BODY (switch_expr
) = NULL
;
1276 gcc_assert (SWITCH_LABELS (switch_expr
));
1281 static enum gimplify_status
1282 gimplify_case_label_expr (tree
*expr_p
)
1284 tree expr
= *expr_p
;
1286 gcc_assert (gimplify_ctxp
->case_labels
);
1287 VEC_safe_push (tree
, heap
, gimplify_ctxp
->case_labels
, expr
);
1288 *expr_p
= build (LABEL_EXPR
, void_type_node
, CASE_LABEL (expr
));
1292 /* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
1296 build_and_jump (tree
*label_p
)
1298 if (label_p
== NULL
)
1299 /* If there's nowhere to jump, just fall through. */
1302 if (*label_p
== NULL_TREE
)
1304 tree label
= create_artificial_label ();
1308 return build1 (GOTO_EXPR
, void_type_node
, *label_p
);
1311 /* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
1312 This also involves building a label to jump to and communicating it to
1313 gimplify_loop_expr through gimplify_ctxp->exit_label. */
1315 static enum gimplify_status
1316 gimplify_exit_expr (tree
*expr_p
)
1318 tree cond
= TREE_OPERAND (*expr_p
, 0);
1321 expr
= build_and_jump (&gimplify_ctxp
->exit_label
);
1322 expr
= build (COND_EXPR
, void_type_node
, cond
, expr
, NULL_TREE
);
1328 /* A helper function to be called via walk_tree. Mark all labels under *TP
1329 as being forced. To be called for DECL_INITIAL of static variables. */
1332 force_labels_r (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1336 if (TREE_CODE (*tp
) == LABEL_DECL
)
1337 FORCED_LABEL (*tp
) = 1;
1342 /* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is
1343 different from its canonical type, wrap the whole thing inside a
1344 NOP_EXPR and force the type of the COMPONENT_REF to be the canonical
1347 The canonical type of a COMPONENT_REF is the type of the field being
1348 referenced--unless the field is a bit-field which can be read directly
1349 in a smaller mode, in which case the canonical type is the
1350 sign-appropriate type corresponding to that mode. */
1353 canonicalize_component_ref (tree
*expr_p
)
1355 tree expr
= *expr_p
;
1358 gcc_assert (TREE_CODE (expr
) == COMPONENT_REF
);
1360 if (INTEGRAL_TYPE_P (TREE_TYPE (expr
)))
1361 type
= TREE_TYPE (get_unwidened (expr
, NULL_TREE
));
1363 type
= TREE_TYPE (TREE_OPERAND (expr
, 1));
1365 if (TREE_TYPE (expr
) != type
)
1367 tree old_type
= TREE_TYPE (expr
);
1369 /* Set the type of the COMPONENT_REF to the underlying type. */
1370 TREE_TYPE (expr
) = type
;
1372 /* And wrap the whole thing inside a NOP_EXPR. */
1373 expr
= build1 (NOP_EXPR
, old_type
, expr
);
1379 /* If a NOP conversion is changing a pointer to array of foo to a pointer
1380 to foo, embed that change in the ADDR_EXPR by converting
1385 where L is the lower bound. For simplicity, only do this for constant
1389 canonicalize_addr_expr (tree
*expr_p
)
1391 tree expr
= *expr_p
;
1392 tree ctype
= TREE_TYPE (expr
);
1393 tree addr_expr
= TREE_OPERAND (expr
, 0);
1394 tree atype
= TREE_TYPE (addr_expr
);
1395 tree dctype
, datype
, ddatype
, otype
, obj_expr
;
1397 /* Both cast and addr_expr types should be pointers. */
1398 if (!POINTER_TYPE_P (ctype
) || !POINTER_TYPE_P (atype
))
1401 /* The addr_expr type should be a pointer to an array. */
1402 datype
= TREE_TYPE (atype
);
1403 if (TREE_CODE (datype
) != ARRAY_TYPE
)
1406 /* Both cast and addr_expr types should address the same object type. */
1407 dctype
= TREE_TYPE (ctype
);
1408 ddatype
= TREE_TYPE (datype
);
1409 if (!lang_hooks
.types_compatible_p (ddatype
, dctype
))
1412 /* The addr_expr and the object type should match. */
1413 obj_expr
= TREE_OPERAND (addr_expr
, 0);
1414 otype
= TREE_TYPE (obj_expr
);
1415 if (!lang_hooks
.types_compatible_p (otype
, datype
))
1418 /* The lower bound and element sizes must be constant. */
1419 if (!TYPE_SIZE_UNIT (dctype
)
1420 || TREE_CODE (TYPE_SIZE_UNIT (dctype
)) != INTEGER_CST
1421 || !TYPE_DOMAIN (datype
) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype
))
1422 || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype
))) != INTEGER_CST
)
1425 /* All checks succeeded. Build a new node to merge the cast. */
1426 *expr_p
= build4 (ARRAY_REF
, dctype
, obj_expr
,
1427 TYPE_MIN_VALUE (TYPE_DOMAIN (datype
)),
1428 TYPE_MIN_VALUE (TYPE_DOMAIN (datype
)),
1429 size_binop (EXACT_DIV_EXPR
, TYPE_SIZE_UNIT (dctype
),
1430 size_int (TYPE_ALIGN_UNIT (dctype
))));
1431 *expr_p
= build1 (ADDR_EXPR
, ctype
, *expr_p
);
1434 /* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
1435 underneath as appropriate. */
1437 static enum gimplify_status
1438 gimplify_conversion (tree
*expr_p
)
1440 gcc_assert (TREE_CODE (*expr_p
) == NOP_EXPR
1441 || TREE_CODE (*expr_p
) == CONVERT_EXPR
);
1443 /* Then strip away all but the outermost conversion. */
1444 STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p
, 0));
1446 /* And remove the outermost conversion if it's useless. */
1447 if (tree_ssa_useless_type_conversion (*expr_p
))
1448 *expr_p
= TREE_OPERAND (*expr_p
, 0);
1450 /* If we still have a conversion at the toplevel,
1451 then canonicalize some constructs. */
1452 if (TREE_CODE (*expr_p
) == NOP_EXPR
|| TREE_CODE (*expr_p
) == CONVERT_EXPR
)
1454 tree sub
= TREE_OPERAND (*expr_p
, 0);
1456 /* If a NOP conversion is changing the type of a COMPONENT_REF
1457 expression, then canonicalize its type now in order to expose more
1458 redundant conversions. */
1459 if (TREE_CODE (sub
) == COMPONENT_REF
)
1460 canonicalize_component_ref (&TREE_OPERAND (*expr_p
, 0));
1462 /* If a NOP conversion is changing a pointer to array of foo
1463 to a pointer to foo, embed that change in the ADDR_EXPR. */
1464 else if (TREE_CODE (sub
) == ADDR_EXPR
)
1465 canonicalize_addr_expr (expr_p
);
1471 /* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
1472 node pointed to by EXPR_P.
1475 : min_lval '[' val ']'
1477 | compound_lval '[' val ']'
1478 | compound_lval '.' ID
1480 This is not part of the original SIMPLE definition, which separates
1481 array and member references, but it seems reasonable to handle them
1482 together. Also, this way we don't run into problems with union
1483 aliasing; gcc requires that for accesses through a union to alias, the
1484 union reference must be explicit, which was not always the case when we
1485 were splitting up array and member refs.
1487 PRE_P points to the list where side effects that must happen before
1488 *EXPR_P should be stored.
1490 POST_P points to the list where side effects that must happen after
1491 *EXPR_P should be stored. */
1493 static enum gimplify_status
1494 gimplify_compound_lval (tree
*expr_p
, tree
*pre_p
,
1495 tree
*post_p
, fallback_t fallback
)
1498 VEC(tree
,heap
) *stack
;
1499 enum gimplify_status ret
= GS_OK
, tret
;
1502 /* Create a stack of the subexpressions so later we can walk them in
1503 order from inner to outer. */
1504 stack
= VEC_alloc (tree
, heap
, 10);
1506 /* We can handle anything that get_inner_reference can deal with. */
1507 for (p
= expr_p
; ; p
= &TREE_OPERAND (*p
, 0))
1509 /* Fold INDIRECT_REFs now to turn them into ARRAY_REFs. */
1510 if (TREE_CODE (*p
) == INDIRECT_REF
)
1511 *p
= fold_indirect_ref (*p
);
1512 if (!handled_component_p (*p
))
1514 VEC_safe_push (tree
, heap
, stack
, *p
);
1517 gcc_assert (VEC_length (tree
, stack
));
1519 /* Now STACK is a stack of pointers to all the refs we've walked through
1520 and P points to the innermost expression.
1522 Java requires that we elaborated nodes in source order. That
1523 means we must gimplify the inner expression followed by each of
1524 the indices, in order. But we can't gimplify the inner
1525 expression until we deal with any variable bounds, sizes, or
1526 positions in order to deal with PLACEHOLDER_EXPRs.
1528 So we do this in three steps. First we deal with the annotations
1529 for any variables in the components, then we gimplify the base,
1530 then we gimplify any indices, from left to right. */
1531 for (i
= VEC_length (tree
, stack
) - 1; i
>= 0; i
--)
1533 tree t
= VEC_index (tree
, stack
, i
);
1535 if (TREE_CODE (t
) == ARRAY_REF
|| TREE_CODE (t
) == ARRAY_RANGE_REF
)
1537 /* Gimplify the low bound and element type size and put them into
1538 the ARRAY_REF. If these values are set, they have already been
1540 if (!TREE_OPERAND (t
, 2))
1542 tree low
= unshare_expr (array_ref_low_bound (t
));
1543 if (!is_gimple_min_invariant (low
))
1545 TREE_OPERAND (t
, 2) = low
;
1546 tret
= gimplify_expr (&TREE_OPERAND (t
, 2), pre_p
, post_p
,
1547 is_gimple_formal_tmp_reg
, fb_rvalue
);
1548 ret
= MIN (ret
, tret
);
1552 if (!TREE_OPERAND (t
, 3))
1554 tree elmt_type
= TREE_TYPE (TREE_TYPE (TREE_OPERAND (t
, 0)));
1555 tree elmt_size
= unshare_expr (array_ref_element_size (t
));
1556 tree factor
= size_int (TYPE_ALIGN_UNIT (elmt_type
));
1558 /* Divide the element size by the alignment of the element
1560 elmt_size
= size_binop (EXACT_DIV_EXPR
, elmt_size
, factor
);
1562 if (!is_gimple_min_invariant (elmt_size
))
1564 TREE_OPERAND (t
, 3) = elmt_size
;
1565 tret
= gimplify_expr (&TREE_OPERAND (t
, 3), pre_p
, post_p
,
1566 is_gimple_formal_tmp_reg
, fb_rvalue
);
1567 ret
= MIN (ret
, tret
);
1571 else if (TREE_CODE (t
) == COMPONENT_REF
)
1573 /* Set the field offset into T and gimplify it. */
1574 if (!TREE_OPERAND (t
, 2))
1576 tree offset
= unshare_expr (component_ref_field_offset (t
));
1577 tree field
= TREE_OPERAND (t
, 1);
1579 = size_int (DECL_OFFSET_ALIGN (field
) / BITS_PER_UNIT
);
1581 /* Divide the offset by its alignment. */
1582 offset
= size_binop (EXACT_DIV_EXPR
, offset
, factor
);
1584 if (!is_gimple_min_invariant (offset
))
1586 TREE_OPERAND (t
, 2) = offset
;
1587 tret
= gimplify_expr (&TREE_OPERAND (t
, 2), pre_p
, post_p
,
1588 is_gimple_formal_tmp_reg
, fb_rvalue
);
1589 ret
= MIN (ret
, tret
);
1595 /* Step 2 is to gimplify the base expression. */
1596 tret
= gimplify_expr (p
, pre_p
, post_p
, is_gimple_min_lval
, fallback
);
1597 ret
= MIN (ret
, tret
);
1599 /* And finally, the indices and operands to BIT_FIELD_REF. During this
1600 loop we also remove any useless conversions. */
1601 for (; VEC_length (tree
, stack
) > 0; )
1603 tree t
= VEC_pop (tree
, stack
);
1605 if (TREE_CODE (t
) == ARRAY_REF
|| TREE_CODE (t
) == ARRAY_RANGE_REF
)
1607 /* Gimplify the dimension.
1608 Temporary fix for gcc.c-torture/execute/20040313-1.c.
1609 Gimplify non-constant array indices into a temporary
1611 FIXME - The real fix is to gimplify post-modify
1612 expressions into a minimal gimple lvalue. However, that
1613 exposes bugs in alias analysis. The alias analyzer does
1614 not handle &PTR->FIELD very well. Will fix after the
1615 branch is merged into mainline (dnovillo 2004-05-03). */
1616 if (!is_gimple_min_invariant (TREE_OPERAND (t
, 1)))
1618 tret
= gimplify_expr (&TREE_OPERAND (t
, 1), pre_p
, post_p
,
1619 is_gimple_formal_tmp_reg
, fb_rvalue
);
1620 ret
= MIN (ret
, tret
);
1623 else if (TREE_CODE (t
) == BIT_FIELD_REF
)
1625 tret
= gimplify_expr (&TREE_OPERAND (t
, 1), pre_p
, post_p
,
1626 is_gimple_val
, fb_rvalue
);
1627 ret
= MIN (ret
, tret
);
1628 tret
= gimplify_expr (&TREE_OPERAND (t
, 2), pre_p
, post_p
,
1629 is_gimple_val
, fb_rvalue
);
1630 ret
= MIN (ret
, tret
);
1633 STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t
, 0));
1635 /* The innermost expression P may have originally had TREE_SIDE_EFFECTS
1636 set which would have caused all the outer expressions in EXPR_P
1637 leading to P to also have had TREE_SIDE_EFFECTS set. */
1638 recalculate_side_effects (t
);
1641 tret
= gimplify_expr (p
, pre_p
, post_p
, is_gimple_min_lval
, fallback
);
1642 ret
= MIN (ret
, tret
);
1644 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
1645 if ((fallback
& fb_rvalue
) && TREE_CODE (*expr_p
) == COMPONENT_REF
)
1647 canonicalize_component_ref (expr_p
);
1648 ret
= MIN (ret
, GS_OK
);
1651 VEC_free (tree
, heap
, stack
);
1656 /* Gimplify the self modifying expression pointed to by EXPR_P
1659 PRE_P points to the list where side effects that must happen before
1660 *EXPR_P should be stored.
1662 POST_P points to the list where side effects that must happen after
1663 *EXPR_P should be stored.
1665 WANT_VALUE is nonzero iff we want to use the value of this expression
1666 in another expression. */
1668 static enum gimplify_status
1669 gimplify_self_mod_expr (tree
*expr_p
, tree
*pre_p
, tree
*post_p
,
1672 enum tree_code code
;
1673 tree lhs
, lvalue
, rhs
, t1
;
1675 enum tree_code arith_code
;
1676 enum gimplify_status ret
;
1678 code
= TREE_CODE (*expr_p
);
1680 gcc_assert (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
1681 || code
== PREINCREMENT_EXPR
|| code
== PREDECREMENT_EXPR
);
1683 /* Prefix or postfix? */
1684 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
1685 /* Faster to treat as prefix if result is not used. */
1686 postfix
= want_value
;
1690 /* Add or subtract? */
1691 if (code
== PREINCREMENT_EXPR
|| code
== POSTINCREMENT_EXPR
)
1692 arith_code
= PLUS_EXPR
;
1694 arith_code
= MINUS_EXPR
;
1696 /* Gimplify the LHS into a GIMPLE lvalue. */
1697 lvalue
= TREE_OPERAND (*expr_p
, 0);
1698 ret
= gimplify_expr (&lvalue
, pre_p
, post_p
, is_gimple_lvalue
, fb_lvalue
);
1699 if (ret
== GS_ERROR
)
1702 /* Extract the operands to the arithmetic operation. */
1704 rhs
= TREE_OPERAND (*expr_p
, 1);
1706 /* For postfix operator, we evaluate the LHS to an rvalue and then use
1707 that as the result value and in the postqueue operation. */
1710 ret
= gimplify_expr (&lhs
, pre_p
, post_p
, is_gimple_val
, fb_rvalue
);
1711 if (ret
== GS_ERROR
)
1715 t1
= build (arith_code
, TREE_TYPE (*expr_p
), lhs
, rhs
);
1716 t1
= build (MODIFY_EXPR
, TREE_TYPE (lvalue
), lvalue
, t1
);
1720 gimplify_and_add (t1
, post_p
);
1731 /* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
1734 maybe_with_size_expr (tree
*expr_p
)
1736 tree expr
= *expr_p
;
1737 tree type
= TREE_TYPE (expr
);
1740 /* If we've already wrapped this or the type is error_mark_node, we can't do
1742 if (TREE_CODE (expr
) == WITH_SIZE_EXPR
1743 || type
== error_mark_node
)
1746 /* If the size isn't known or is a constant, we have nothing to do. */
1747 size
= TYPE_SIZE_UNIT (type
);
1748 if (!size
|| TREE_CODE (size
) == INTEGER_CST
)
1751 /* Otherwise, make a WITH_SIZE_EXPR. */
1752 size
= unshare_expr (size
);
1753 size
= SUBSTITUTE_PLACEHOLDER_IN_EXPR (size
, expr
);
1754 *expr_p
= build2 (WITH_SIZE_EXPR
, type
, expr
, size
);
1757 /* Subroutine of gimplify_call_expr: Gimplify a single argument. */
1759 static enum gimplify_status
1760 gimplify_arg (tree
*expr_p
, tree
*pre_p
)
1762 bool (*test
) (tree
);
1765 /* In general, we allow lvalues for function arguments to avoid
1766 extra overhead of copying large aggregates out of even larger
1767 aggregates into temporaries only to copy the temporaries to
1768 the argument list. Make optimizers happy by pulling out to
1769 temporaries those types that fit in registers. */
1770 if (is_gimple_reg_type (TREE_TYPE (*expr_p
)))
1771 test
= is_gimple_val
, fb
= fb_rvalue
;
1773 test
= is_gimple_lvalue
, fb
= fb_either
;
1775 /* If this is a variable sized type, we must remember the size. */
1776 maybe_with_size_expr (expr_p
);
1778 /* There is a sequence point before a function call. Side effects in
1779 the argument list must occur before the actual call. So, when
1780 gimplifying arguments, force gimplify_expr to use an internal
1781 post queue which is then appended to the end of PRE_P. */
1782 return gimplify_expr (expr_p
, pre_p
, NULL
, test
, fb
);
1785 /* Gimplify the CALL_EXPR node pointed to by EXPR_P. PRE_P points to the
1786 list where side effects that must happen before *EXPR_P should be stored.
1787 WANT_VALUE is true if the result of the call is desired. */
1789 static enum gimplify_status
1790 gimplify_call_expr (tree
*expr_p
, tree
*pre_p
, bool want_value
)
1794 enum gimplify_status ret
;
1796 gcc_assert (TREE_CODE (*expr_p
) == CALL_EXPR
);
1798 /* For reliable diagnostics during inlining, it is necessary that
1799 every call_expr be annotated with file and line. */
1800 if (! EXPR_HAS_LOCATION (*expr_p
))
1801 SET_EXPR_LOCATION (*expr_p
, input_location
);
1803 /* This may be a call to a builtin function.
1805 Builtin function calls may be transformed into different
1806 (and more efficient) builtin function calls under certain
1807 circumstances. Unfortunately, gimplification can muck things
1808 up enough that the builtin expanders are not aware that certain
1809 transformations are still valid.
1811 So we attempt transformation/gimplification of the call before
1812 we gimplify the CALL_EXPR. At this time we do not manage to
1813 transform all calls in the same manner as the expanders do, but
1814 we do transform most of them. */
1815 decl
= get_callee_fndecl (*expr_p
);
1816 if (decl
&& DECL_BUILT_IN (decl
))
1818 tree fndecl
= get_callee_fndecl (*expr_p
);
1819 tree arglist
= TREE_OPERAND (*expr_p
, 1);
1820 tree
new = fold_builtin (fndecl
, arglist
, !want_value
);
1822 if (new && new != *expr_p
)
1824 /* There was a transformation of this call which computes the
1825 same value, but in a more efficient way. Return and try
1831 if (DECL_BUILT_IN_CLASS (decl
) == BUILT_IN_NORMAL
1832 && DECL_FUNCTION_CODE (decl
) == BUILT_IN_VA_START
)
1834 if (!arglist
|| !TREE_CHAIN (arglist
))
1836 error ("too few arguments to function %<va_start%>");
1837 *expr_p
= build_empty_stmt ();
1841 if (fold_builtin_next_arg (TREE_CHAIN (arglist
)))
1843 *expr_p
= build_empty_stmt ();
1846 /* Avoid gimplifying the second argument to va_start, which needs
1847 to be the plain PARM_DECL. */
1848 return gimplify_arg (&TREE_VALUE (TREE_OPERAND (*expr_p
, 1)), pre_p
);
1852 /* There is a sequence point before the call, so any side effects in
1853 the calling expression must occur before the actual call. Force
1854 gimplify_expr to use an internal post queue. */
1855 ret
= gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
, NULL
,
1856 is_gimple_call_addr
, fb_rvalue
);
1858 if (PUSH_ARGS_REVERSED
)
1859 TREE_OPERAND (*expr_p
, 1) = nreverse (TREE_OPERAND (*expr_p
, 1));
1860 for (arglist
= TREE_OPERAND (*expr_p
, 1); arglist
;
1861 arglist
= TREE_CHAIN (arglist
))
1863 enum gimplify_status t
;
1865 t
= gimplify_arg (&TREE_VALUE (arglist
), pre_p
);
1870 if (PUSH_ARGS_REVERSED
)
1871 TREE_OPERAND (*expr_p
, 1) = nreverse (TREE_OPERAND (*expr_p
, 1));
1873 /* Try this again in case gimplification exposed something. */
1874 if (ret
!= GS_ERROR
&& decl
&& DECL_BUILT_IN (decl
))
1876 tree fndecl
= get_callee_fndecl (*expr_p
);
1877 tree arglist
= TREE_OPERAND (*expr_p
, 1);
1878 tree
new = fold_builtin (fndecl
, arglist
, !want_value
);
1880 if (new && new != *expr_p
)
1882 /* There was a transformation of this call which computes the
1883 same value, but in a more efficient way. Return and try
1890 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
1891 decl. This allows us to eliminate redundant or useless
1892 calls to "const" functions. */
1893 if (TREE_CODE (*expr_p
) == CALL_EXPR
1894 && (call_expr_flags (*expr_p
) & (ECF_CONST
| ECF_PURE
)))
1895 TREE_SIDE_EFFECTS (*expr_p
) = 0;
1900 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
1901 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
1903 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
1904 condition is true or false, respectively. If null, we should generate
1905 our own to skip over the evaluation of this specific expression.
1907 This function is the tree equivalent of do_jump.
1909 shortcut_cond_r should only be called by shortcut_cond_expr. */
1912 shortcut_cond_r (tree pred
, tree
*true_label_p
, tree
*false_label_p
)
1914 tree local_label
= NULL_TREE
;
1915 tree t
, expr
= NULL
;
1917 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
1918 retain the shortcut semantics. Just insert the gotos here;
1919 shortcut_cond_expr will append the real blocks later. */
1920 if (TREE_CODE (pred
) == TRUTH_ANDIF_EXPR
)
1922 /* Turn if (a && b) into
1924 if (a); else goto no;
1925 if (b) goto yes; else goto no;
1928 if (false_label_p
== NULL
)
1929 false_label_p
= &local_label
;
1931 t
= shortcut_cond_r (TREE_OPERAND (pred
, 0), NULL
, false_label_p
);
1932 append_to_statement_list (t
, &expr
);
1934 t
= shortcut_cond_r (TREE_OPERAND (pred
, 1), true_label_p
,
1936 append_to_statement_list (t
, &expr
);
1938 else if (TREE_CODE (pred
) == TRUTH_ORIF_EXPR
)
1940 /* Turn if (a || b) into
1943 if (b) goto yes; else goto no;
1946 if (true_label_p
== NULL
)
1947 true_label_p
= &local_label
;
1949 t
= shortcut_cond_r (TREE_OPERAND (pred
, 0), true_label_p
, NULL
);
1950 append_to_statement_list (t
, &expr
);
1952 t
= shortcut_cond_r (TREE_OPERAND (pred
, 1), true_label_p
,
1954 append_to_statement_list (t
, &expr
);
1956 else if (TREE_CODE (pred
) == COND_EXPR
)
1958 /* As long as we're messing with gotos, turn if (a ? b : c) into
1960 if (b) goto yes; else goto no;
1962 if (c) goto yes; else goto no; */
1963 expr
= build (COND_EXPR
, void_type_node
, TREE_OPERAND (pred
, 0),
1964 shortcut_cond_r (TREE_OPERAND (pred
, 1), true_label_p
,
1966 shortcut_cond_r (TREE_OPERAND (pred
, 2), true_label_p
,
1971 expr
= build (COND_EXPR
, void_type_node
, pred
,
1972 build_and_jump (true_label_p
),
1973 build_and_jump (false_label_p
));
1978 t
= build1 (LABEL_EXPR
, void_type_node
, local_label
);
1979 append_to_statement_list (t
, &expr
);
1986 shortcut_cond_expr (tree expr
)
1988 tree pred
= TREE_OPERAND (expr
, 0);
1989 tree then_
= TREE_OPERAND (expr
, 1);
1990 tree else_
= TREE_OPERAND (expr
, 2);
1991 tree true_label
, false_label
, end_label
, t
;
1993 tree
*false_label_p
;
1994 bool emit_end
, emit_false
, jump_over_else
;
1995 bool then_se
= then_
&& TREE_SIDE_EFFECTS (then_
);
1996 bool else_se
= else_
&& TREE_SIDE_EFFECTS (else_
);
1998 /* First do simple transformations. */
2001 /* If there is no 'else', turn (a && b) into if (a) if (b). */
2002 while (TREE_CODE (pred
) == TRUTH_ANDIF_EXPR
)
2004 TREE_OPERAND (expr
, 0) = TREE_OPERAND (pred
, 1);
2005 then_
= shortcut_cond_expr (expr
);
2006 then_se
= then_
&& TREE_SIDE_EFFECTS (then_
);
2007 pred
= TREE_OPERAND (pred
, 0);
2008 expr
= build (COND_EXPR
, void_type_node
, pred
, then_
, NULL_TREE
);
2013 /* If there is no 'then', turn
2016 if (a); else if (b); else d. */
2017 while (TREE_CODE (pred
) == TRUTH_ORIF_EXPR
)
2019 TREE_OPERAND (expr
, 0) = TREE_OPERAND (pred
, 1);
2020 else_
= shortcut_cond_expr (expr
);
2021 else_se
= else_
&& TREE_SIDE_EFFECTS (else_
);
2022 pred
= TREE_OPERAND (pred
, 0);
2023 expr
= build (COND_EXPR
, void_type_node
, pred
, NULL_TREE
, else_
);
2027 /* If we're done, great. */
2028 if (TREE_CODE (pred
) != TRUTH_ANDIF_EXPR
2029 && TREE_CODE (pred
) != TRUTH_ORIF_EXPR
)
2032 /* Otherwise we need to mess with gotos. Change
2035 if (a); else goto no;
2038 and recursively gimplify the condition. */
2040 true_label
= false_label
= end_label
= NULL_TREE
;
2042 /* If our arms just jump somewhere, hijack those labels so we don't
2043 generate jumps to jumps. */
2046 && TREE_CODE (then_
) == GOTO_EXPR
2047 && TREE_CODE (GOTO_DESTINATION (then_
)) == LABEL_DECL
)
2049 true_label
= GOTO_DESTINATION (then_
);
2055 && TREE_CODE (else_
) == GOTO_EXPR
2056 && TREE_CODE (GOTO_DESTINATION (else_
)) == LABEL_DECL
)
2058 false_label
= GOTO_DESTINATION (else_
);
2063 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2065 true_label_p
= &true_label
;
2067 true_label_p
= NULL
;
2069 /* The 'else' branch also needs a label if it contains interesting code. */
2070 if (false_label
|| else_se
)
2071 false_label_p
= &false_label
;
2073 false_label_p
= NULL
;
2075 /* If there was nothing else in our arms, just forward the label(s). */
2076 if (!then_se
&& !else_se
)
2077 return shortcut_cond_r (pred
, true_label_p
, false_label_p
);
2079 /* If our last subexpression already has a terminal label, reuse it. */
2081 expr
= expr_last (else_
);
2083 expr
= expr_last (then_
);
2086 if (expr
&& TREE_CODE (expr
) == LABEL_EXPR
)
2087 end_label
= LABEL_EXPR_LABEL (expr
);
2089 /* If we don't care about jumping to the 'else' branch, jump to the end
2090 if the condition is false. */
2092 false_label_p
= &end_label
;
2094 /* We only want to emit these labels if we aren't hijacking them. */
2095 emit_end
= (end_label
== NULL_TREE
);
2096 emit_false
= (false_label
== NULL_TREE
);
2098 /* We only emit the jump over the else clause if we have to--if the
2099 then clause may fall through. Otherwise we can wind up with a
2100 useless jump and a useless label at the end of gimplified code,
2101 which will cause us to think that this conditional as a whole
2102 falls through even if it doesn't. If we then inline a function
2103 which ends with such a condition, that can cause us to issue an
2104 inappropriate warning about control reaching the end of a
2105 non-void function. */
2106 jump_over_else
= block_may_fallthru (then_
);
2108 pred
= shortcut_cond_r (pred
, true_label_p
, false_label_p
);
2111 append_to_statement_list (pred
, &expr
);
2113 append_to_statement_list (then_
, &expr
);
2118 t
= build_and_jump (&end_label
);
2119 append_to_statement_list (t
, &expr
);
2123 t
= build1 (LABEL_EXPR
, void_type_node
, false_label
);
2124 append_to_statement_list (t
, &expr
);
2126 append_to_statement_list (else_
, &expr
);
2128 if (emit_end
&& end_label
)
2130 t
= build1 (LABEL_EXPR
, void_type_node
, end_label
);
2131 append_to_statement_list (t
, &expr
);
2137 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2140 gimple_boolify (tree expr
)
2142 tree type
= TREE_TYPE (expr
);
2144 if (TREE_CODE (type
) == BOOLEAN_TYPE
)
2147 switch (TREE_CODE (expr
))
2149 case TRUTH_AND_EXPR
:
2151 case TRUTH_XOR_EXPR
:
2152 case TRUTH_ANDIF_EXPR
:
2153 case TRUTH_ORIF_EXPR
:
2154 /* Also boolify the arguments of truth exprs. */
2155 TREE_OPERAND (expr
, 1) = gimple_boolify (TREE_OPERAND (expr
, 1));
2158 case TRUTH_NOT_EXPR
:
2159 TREE_OPERAND (expr
, 0) = gimple_boolify (TREE_OPERAND (expr
, 0));
2162 case EQ_EXPR
: case NE_EXPR
:
2163 case LE_EXPR
: case GE_EXPR
: case LT_EXPR
: case GT_EXPR
:
2164 /* These expressions always produce boolean results. */
2165 TREE_TYPE (expr
) = boolean_type_node
;
2169 /* Other expressions that get here must have boolean values, but
2170 might need to be converted to the appropriate mode. */
2171 return convert (boolean_type_node
, expr
);
2175 /* Convert the conditional expression pointed to by EXPR_P '(p) ? a : b;'
2184 The second form is used when *EXPR_P is of type void.
2186 TARGET is the tree for T1 above.
2188 PRE_P points to the list where side effects that must happen before
2189 *EXPR_P should be stored.
2191 POST_P points to the list where side effects that must happen after
2192 *EXPR_P should be stored. */
2194 static enum gimplify_status
2195 gimplify_cond_expr (tree
*expr_p
, tree
*pre_p
, tree
*post_p
, tree target
,
2196 fallback_t fallback
)
2198 tree expr
= *expr_p
;
2199 tree tmp
, tmp2
, type
;
2200 enum gimplify_status ret
;
2202 type
= TREE_TYPE (expr
);
2204 /* If this COND_EXPR has a value, copy the values into a temporary within
2206 if (! VOID_TYPE_P (type
))
2212 ret
= gimplify_expr (&target
, pre_p
, post_p
,
2213 is_gimple_min_lval
, fb_lvalue
);
2214 if (ret
!= GS_ERROR
)
2216 result
= tmp
= target
;
2217 tmp2
= unshare_expr (target
);
2219 else if ((fallback
& fb_lvalue
) == 0)
2221 result
= tmp2
= tmp
= create_tmp_var (TREE_TYPE (expr
), "iftmp");
2226 tree type
= build_pointer_type (TREE_TYPE (expr
));
2228 if (TREE_TYPE (TREE_OPERAND (expr
, 1)) != void_type_node
)
2229 TREE_OPERAND (expr
, 1) =
2230 build_fold_addr_expr (TREE_OPERAND (expr
, 1));
2232 if (TREE_TYPE (TREE_OPERAND (expr
, 2)) != void_type_node
)
2233 TREE_OPERAND (expr
, 2) =
2234 build_fold_addr_expr (TREE_OPERAND (expr
, 2));
2236 tmp2
= tmp
= create_tmp_var (type
, "iftmp");
2238 expr
= build (COND_EXPR
, void_type_node
, TREE_OPERAND (expr
, 0),
2239 TREE_OPERAND (expr
, 1), TREE_OPERAND (expr
, 2));
2241 result
= build_fold_indirect_ref (tmp
);
2245 /* Build the then clause, 't1 = a;'. But don't build an assignment
2246 if this branch is void; in C++ it can be, if it's a throw. */
2247 if (TREE_TYPE (TREE_OPERAND (expr
, 1)) != void_type_node
)
2248 TREE_OPERAND (expr
, 1)
2249 = build (MODIFY_EXPR
, void_type_node
, tmp
, TREE_OPERAND (expr
, 1));
2251 /* Build the else clause, 't1 = b;'. */
2252 if (TREE_TYPE (TREE_OPERAND (expr
, 2)) != void_type_node
)
2253 TREE_OPERAND (expr
, 2)
2254 = build (MODIFY_EXPR
, void_type_node
, tmp2
, TREE_OPERAND (expr
, 2));
2256 TREE_TYPE (expr
) = void_type_node
;
2257 recalculate_side_effects (expr
);
2259 /* Move the COND_EXPR to the prequeue. */
2260 gimplify_and_add (expr
, pre_p
);
2266 /* Make sure the condition has BOOLEAN_TYPE. */
2267 TREE_OPERAND (expr
, 0) = gimple_boolify (TREE_OPERAND (expr
, 0));
2269 /* Break apart && and || conditions. */
2270 if (TREE_CODE (TREE_OPERAND (expr
, 0)) == TRUTH_ANDIF_EXPR
2271 || TREE_CODE (TREE_OPERAND (expr
, 0)) == TRUTH_ORIF_EXPR
)
2273 expr
= shortcut_cond_expr (expr
);
2275 if (expr
!= *expr_p
)
2279 /* We can't rely on gimplify_expr to re-gimplify the expanded
2280 form properly, as cleanups might cause the target labels to be
2281 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2282 set up a conditional context. */
2283 gimple_push_condition ();
2284 gimplify_stmt (expr_p
);
2285 gimple_pop_condition (pre_p
);
2291 /* Now do the normal gimplification. */
2292 ret
= gimplify_expr (&TREE_OPERAND (expr
, 0), pre_p
, NULL
,
2293 is_gimple_condexpr
, fb_rvalue
);
2295 gimple_push_condition ();
2297 gimplify_to_stmt_list (&TREE_OPERAND (expr
, 1));
2298 gimplify_to_stmt_list (&TREE_OPERAND (expr
, 2));
2299 recalculate_side_effects (expr
);
2301 gimple_pop_condition (pre_p
);
2303 if (ret
== GS_ERROR
)
2305 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr
, 1)))
2307 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr
, 2)))
2308 /* Rewrite "if (a); else b" to "if (!a) b" */
2310 TREE_OPERAND (expr
, 0) = invert_truthvalue (TREE_OPERAND (expr
, 0));
2311 ret
= gimplify_expr (&TREE_OPERAND (expr
, 0), pre_p
, NULL
,
2312 is_gimple_condexpr
, fb_rvalue
);
2314 tmp
= TREE_OPERAND (expr
, 1);
2315 TREE_OPERAND (expr
, 1) = TREE_OPERAND (expr
, 2);
2316 TREE_OPERAND (expr
, 2) = tmp
;
2319 /* Both arms are empty; replace the COND_EXPR with its predicate. */
2320 expr
= TREE_OPERAND (expr
, 0);
2326 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2327 a call to __builtin_memcpy. */
2329 static enum gimplify_status
2330 gimplify_modify_expr_to_memcpy (tree
*expr_p
, tree size
, bool want_value
)
2332 tree args
, t
, to
, to_ptr
, from
;
2334 to
= TREE_OPERAND (*expr_p
, 0);
2335 from
= TREE_OPERAND (*expr_p
, 1);
2337 args
= tree_cons (NULL
, size
, NULL
);
2339 t
= build_fold_addr_expr (from
);
2340 args
= tree_cons (NULL
, t
, args
);
2342 to_ptr
= build_fold_addr_expr (to
);
2343 args
= tree_cons (NULL
, to_ptr
, args
);
2344 t
= implicit_built_in_decls
[BUILT_IN_MEMCPY
];
2345 t
= build_function_call_expr (t
, args
);
2349 t
= build1 (NOP_EXPR
, TREE_TYPE (to_ptr
), t
);
2350 t
= build1 (INDIRECT_REF
, TREE_TYPE (to
), t
);
2357 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2358 a call to __builtin_memset. In this case we know that the RHS is
2359 a CONSTRUCTOR with an empty element list. */
2361 static enum gimplify_status
2362 gimplify_modify_expr_to_memset (tree
*expr_p
, tree size
, bool want_value
)
2364 tree args
, t
, to
, to_ptr
;
2366 to
= TREE_OPERAND (*expr_p
, 0);
2368 args
= tree_cons (NULL
, size
, NULL
);
2370 args
= tree_cons (NULL
, integer_zero_node
, args
);
2372 to_ptr
= build_fold_addr_expr (to
);
2373 args
= tree_cons (NULL
, to_ptr
, args
);
2374 t
= implicit_built_in_decls
[BUILT_IN_MEMSET
];
2375 t
= build_function_call_expr (t
, args
);
2379 t
= build1 (NOP_EXPR
, TREE_TYPE (to_ptr
), t
);
2380 t
= build1 (INDIRECT_REF
, TREE_TYPE (to
), t
);
2387 /* A subroutine of gimplify_init_ctor_preeval. Called via walk_tree,
2388 determine, cautiously, if a CONSTRUCTOR overlaps the lhs of an
2389 assignment. Returns non-null if we detect a potential overlap. */
2391 struct gimplify_init_ctor_preeval_data
2393 /* The base decl of the lhs object. May be NULL, in which case we
2394 have to assume the lhs is indirect. */
2397 /* The alias set of the lhs object. */
2402 gimplify_init_ctor_preeval_1 (tree
*tp
, int *walk_subtrees
, void *xdata
)
2404 struct gimplify_init_ctor_preeval_data
*data
2405 = (struct gimplify_init_ctor_preeval_data
*) xdata
;
2408 /* If we find the base object, obviously we have overlap. */
2409 if (data
->lhs_base_decl
== t
)
2412 /* If the constructor component is indirect, determine if we have a
2413 potential overlap with the lhs. The only bits of information we
2414 have to go on at this point are addressability and alias sets. */
2415 if (TREE_CODE (t
) == INDIRECT_REF
2416 && (!data
->lhs_base_decl
|| TREE_ADDRESSABLE (data
->lhs_base_decl
))
2417 && alias_sets_conflict_p (data
->lhs_alias_set
, get_alias_set (t
)))
2420 if (IS_TYPE_OR_DECL_P (t
))
2425 /* A subroutine of gimplify_init_constructor. Pre-evaluate *EXPR_P,
2426 force values that overlap with the lhs (as described by *DATA)
2427 into temporaries. */
2430 gimplify_init_ctor_preeval (tree
*expr_p
, tree
*pre_p
, tree
*post_p
,
2431 struct gimplify_init_ctor_preeval_data
*data
)
2433 enum gimplify_status one
;
2435 /* If the value is invariant, then there's nothing to pre-evaluate.
2436 But ensure it doesn't have any side-effects since a SAVE_EXPR is
2437 invariant but has side effects and might contain a reference to
2438 the object we're initializing. */
2439 if (TREE_INVARIANT (*expr_p
) && !TREE_SIDE_EFFECTS (*expr_p
))
2442 /* If the type has non-trivial constructors, we can't pre-evaluate. */
2443 if (TREE_ADDRESSABLE (TREE_TYPE (*expr_p
)))
2446 /* Recurse for nested constructors. */
2447 if (TREE_CODE (*expr_p
) == CONSTRUCTOR
)
2449 unsigned HOST_WIDE_INT ix
;
2450 constructor_elt
*ce
;
2451 VEC(constructor_elt
,gc
) *v
= CONSTRUCTOR_ELTS (*expr_p
);
2453 for (ix
= 0; VEC_iterate (constructor_elt
, v
, ix
, ce
); ix
++)
2454 gimplify_init_ctor_preeval (&ce
->value
, pre_p
, post_p
, data
);
2458 /* We can't preevaluate if the type contains a placeholder. */
2459 if (type_contains_placeholder_p (TREE_TYPE (*expr_p
)))
2462 /* Gimplify the constructor element to something appropriate for the rhs
2463 of a MODIFY_EXPR. Given that we know the lhs is an aggregate, we know
2464 the gimplifier will consider this a store to memory. Doing this
2465 gimplification now means that we won't have to deal with complicated
2466 language-specific trees, nor trees like SAVE_EXPR that can induce
2467 exponential search behavior. */
2468 one
= gimplify_expr (expr_p
, pre_p
, post_p
, is_gimple_mem_rhs
, fb_rvalue
);
2469 if (one
== GS_ERROR
)
2475 /* If we gimplified to a bare decl, we can be sure that it doesn't overlap
2476 with the lhs, since "a = { .x=a }" doesn't make sense. This will
2477 always be true for all scalars, since is_gimple_mem_rhs insists on a
2478 temporary variable for them. */
2479 if (DECL_P (*expr_p
))
2482 /* If this is of variable size, we have no choice but to assume it doesn't
2483 overlap since we can't make a temporary for it. */
2484 if (!TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (*expr_p
))))
2487 /* Otherwise, we must search for overlap ... */
2488 if (!walk_tree (expr_p
, gimplify_init_ctor_preeval_1
, data
, NULL
))
2491 /* ... and if found, force the value into a temporary. */
2492 *expr_p
= get_formal_tmp_var (*expr_p
, pre_p
);
2495 /* A subroutine of gimplify_init_ctor_eval. Create a loop for
2496 a RANGE_EXPR in a CONSTRUCTOR for an array.
2500 object[var] = value;
2507 We increment var _after_ the loop exit check because we might otherwise
2508 fail if upper == TYPE_MAX_VALUE (type for upper).
2510 Note that we never have to deal with SAVE_EXPRs here, because this has
2511 already been taken care of for us, in gimplify_init_ctor_preeval(). */
2513 static void gimplify_init_ctor_eval (tree
, VEC(constructor_elt
,gc
) *,
2517 gimplify_init_ctor_eval_range (tree object
, tree lower
, tree upper
,
2518 tree value
, tree array_elt_type
,
2519 tree
*pre_p
, bool cleared
)
2521 tree loop_entry_label
, loop_exit_label
;
2522 tree var
, var_type
, cref
;
2524 loop_entry_label
= create_artificial_label ();
2525 loop_exit_label
= create_artificial_label ();
2527 /* Create and initialize the index variable. */
2528 var_type
= TREE_TYPE (upper
);
2529 var
= create_tmp_var (var_type
, NULL
);
2530 append_to_statement_list (build2 (MODIFY_EXPR
, var_type
, var
, lower
), pre_p
);
2532 /* Add the loop entry label. */
2533 append_to_statement_list (build1 (LABEL_EXPR
,
2538 /* Build the reference. */
2539 cref
= build4 (ARRAY_REF
, array_elt_type
, unshare_expr (object
),
2540 var
, NULL_TREE
, NULL_TREE
);
2542 /* If we are a constructor, just call gimplify_init_ctor_eval to do
2543 the store. Otherwise just assign value to the reference. */
2545 if (TREE_CODE (value
) == CONSTRUCTOR
)
2546 /* NB we might have to call ourself recursively through
2547 gimplify_init_ctor_eval if the value is a constructor. */
2548 gimplify_init_ctor_eval (cref
, CONSTRUCTOR_ELTS (value
),
2551 append_to_statement_list (build2 (MODIFY_EXPR
, TREE_TYPE (cref
),
2555 /* We exit the loop when the index var is equal to the upper bound. */
2556 gimplify_and_add (build3 (COND_EXPR
, void_type_node
,
2557 build2 (EQ_EXPR
, boolean_type_node
,
2565 /* Otherwise, increment the index var... */
2566 append_to_statement_list (build2 (MODIFY_EXPR
, var_type
, var
,
2567 build2 (PLUS_EXPR
, var_type
, var
,
2568 fold_convert (var_type
,
2569 integer_one_node
))),
2572 /* ...and jump back to the loop entry. */
2573 append_to_statement_list (build1 (GOTO_EXPR
,
2578 /* Add the loop exit label. */
2579 append_to_statement_list (build1 (LABEL_EXPR
,
2585 /* Return true if FDECL is accessing a field that is zero sized. */
2588 zero_sized_field_decl (tree fdecl
)
2590 if (TREE_CODE (fdecl
) == FIELD_DECL
&& DECL_SIZE (fdecl
)
2591 && integer_zerop (DECL_SIZE (fdecl
)))
2596 /* Return true if TYPE is zero sized. */
2599 zero_sized_type (tree type
)
2601 if (AGGREGATE_TYPE_P (type
) && TYPE_SIZE (type
)
2602 && integer_zerop (TYPE_SIZE (type
)))
2607 /* A subroutine of gimplify_init_constructor. Generate individual
2608 MODIFY_EXPRs for a CONSTRUCTOR. OBJECT is the LHS against which the
2609 assignments should happen. ELTS is the CONSTRUCTOR_ELTS of the
2610 CONSTRUCTOR. CLEARED is true if the entire LHS object has been
2614 gimplify_init_ctor_eval (tree object
, VEC(constructor_elt
,gc
) *elts
,
2615 tree
*pre_p
, bool cleared
)
2617 tree array_elt_type
= NULL
;
2618 unsigned HOST_WIDE_INT ix
;
2619 tree purpose
, value
;
2621 if (TREE_CODE (TREE_TYPE (object
)) == ARRAY_TYPE
)
2622 array_elt_type
= TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object
)));
2624 FOR_EACH_CONSTRUCTOR_ELT (elts
, ix
, purpose
, value
)
2628 /* NULL values are created above for gimplification errors. */
2632 if (cleared
&& initializer_zerop (value
))
2635 /* ??? Here's to hoping the front end fills in all of the indices,
2636 so we don't have to figure out what's missing ourselves. */
2637 gcc_assert (purpose
);
2639 /* Skip zero-sized fields, unless value has side-effects. This can
2640 happen with calls to functions returning a zero-sized type, which
2641 we shouldn't discard. As a number of downstream passes don't
2642 expect sets of zero-sized fields, we rely on the gimplification of
2643 the MODIFY_EXPR we make below to drop the assignment statement. */
2644 if (! TREE_SIDE_EFFECTS (value
) && zero_sized_field_decl (purpose
))
2647 /* If we have a RANGE_EXPR, we have to build a loop to assign the
2649 if (TREE_CODE (purpose
) == RANGE_EXPR
)
2651 tree lower
= TREE_OPERAND (purpose
, 0);
2652 tree upper
= TREE_OPERAND (purpose
, 1);
2654 /* If the lower bound is equal to upper, just treat it as if
2655 upper was the index. */
2656 if (simple_cst_equal (lower
, upper
))
2660 gimplify_init_ctor_eval_range (object
, lower
, upper
, value
,
2661 array_elt_type
, pre_p
, cleared
);
2668 cref
= build (ARRAY_REF
, array_elt_type
, unshare_expr (object
),
2669 purpose
, NULL_TREE
, NULL_TREE
);
2673 gcc_assert (TREE_CODE (purpose
) == FIELD_DECL
);
2674 cref
= build (COMPONENT_REF
, TREE_TYPE (purpose
),
2675 unshare_expr (object
), purpose
, NULL_TREE
);
2678 if (TREE_CODE (value
) == CONSTRUCTOR
2679 && TREE_CODE (TREE_TYPE (value
)) != VECTOR_TYPE
)
2680 gimplify_init_ctor_eval (cref
, CONSTRUCTOR_ELTS (value
),
2684 init
= build (MODIFY_EXPR
, TREE_TYPE (cref
), cref
, value
);
2685 gimplify_and_add (init
, pre_p
);
2690 /* A subroutine of gimplify_modify_expr. Break out elements of a
2691 CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.
2693 Note that we still need to clear any elements that don't have explicit
2694 initializers, so if not all elements are initialized we keep the
2695 original MODIFY_EXPR, we just remove all of the constructor elements. */
2697 static enum gimplify_status
2698 gimplify_init_constructor (tree
*expr_p
, tree
*pre_p
,
2699 tree
*post_p
, bool want_value
)
2702 tree ctor
= TREE_OPERAND (*expr_p
, 1);
2703 tree type
= TREE_TYPE (ctor
);
2704 enum gimplify_status ret
;
2705 VEC(constructor_elt
,gc
) *elts
;
2707 if (TREE_CODE (ctor
) != CONSTRUCTOR
)
2708 return GS_UNHANDLED
;
2710 ret
= gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
, post_p
,
2711 is_gimple_lvalue
, fb_lvalue
);
2712 if (ret
== GS_ERROR
)
2714 object
= TREE_OPERAND (*expr_p
, 0);
2716 elts
= CONSTRUCTOR_ELTS (ctor
);
2719 switch (TREE_CODE (type
))
2723 case QUAL_UNION_TYPE
:
2726 struct gimplify_init_ctor_preeval_data preeval_data
;
2727 HOST_WIDE_INT num_type_elements
, num_ctor_elements
;
2728 HOST_WIDE_INT num_nonzero_elements
, num_nonconstant_elements
;
2731 /* Aggregate types must lower constructors to initialization of
2732 individual elements. The exception is that a CONSTRUCTOR node
2733 with no elements indicates zero-initialization of the whole. */
2734 if (VEC_empty (constructor_elt
, elts
))
2737 categorize_ctor_elements (ctor
, &num_nonzero_elements
,
2738 &num_nonconstant_elements
,
2739 &num_ctor_elements
, &cleared
);
2741 /* If a const aggregate variable is being initialized, then it
2742 should never be a lose to promote the variable to be static. */
2743 if (num_nonconstant_elements
== 0
2744 && num_nonzero_elements
> 1
2745 && TREE_READONLY (object
)
2746 && TREE_CODE (object
) == VAR_DECL
)
2748 DECL_INITIAL (object
) = ctor
;
2749 TREE_STATIC (object
) = 1;
2750 if (!DECL_NAME (object
))
2751 DECL_NAME (object
) = create_tmp_var_name ("C");
2752 walk_tree (&DECL_INITIAL (object
), force_labels_r
, NULL
, NULL
);
2754 /* ??? C++ doesn't automatically append a .<number> to the
2755 assembler name, and even when it does, it looks a FE private
2756 data structures to figure out what that number should be,
2757 which are not set for this variable. I suppose this is
2758 important for local statics for inline functions, which aren't
2759 "local" in the object file sense. So in order to get a unique
2760 TU-local symbol, we must invoke the lhd version now. */
2761 lhd_set_decl_assembler_name (object
);
2763 *expr_p
= NULL_TREE
;
2767 /* If there are "lots" of initialized elements, even discounting
2768 those that are not address constants (and thus *must* be
2769 computed at runtime), then partition the constructor into
2770 constant and non-constant parts. Block copy the constant
2771 parts in, then generate code for the non-constant parts. */
2772 /* TODO. There's code in cp/typeck.c to do this. */
2774 num_type_elements
= count_type_elements (type
, true);
2776 /* If count_type_elements could not determine number of type elements
2777 for a constant-sized object, assume clearing is needed.
2778 Don't do this for variable-sized objects, as store_constructor
2779 will ignore the clearing of variable-sized objects. */
2780 if (num_type_elements
< 0 && int_size_in_bytes (type
) >= 0)
2782 /* If there are "lots" of zeros, then block clear the object first. */
2783 else if (num_type_elements
- num_nonzero_elements
> CLEAR_RATIO
2784 && num_nonzero_elements
< num_type_elements
/4)
2786 /* ??? This bit ought not be needed. For any element not present
2787 in the initializer, we should simply set them to zero. Except
2788 we'd need to *find* the elements that are not present, and that
2789 requires trickery to avoid quadratic compile-time behavior in
2790 large cases or excessive memory use in small cases. */
2791 else if (num_ctor_elements
< num_type_elements
)
2794 /* If there are "lots" of initialized elements, and all of them
2795 are valid address constants, then the entire initializer can
2796 be dropped to memory, and then memcpy'd out. Don't do this
2797 for sparse arrays, though, as it's more efficient to follow
2798 the standard CONSTRUCTOR behavior of memset followed by
2799 individual element initialization. */
2800 if (num_nonconstant_elements
== 0 && !cleared
)
2802 HOST_WIDE_INT size
= int_size_in_bytes (type
);
2805 /* ??? We can still get unbounded array types, at least
2806 from the C++ front end. This seems wrong, but attempt
2807 to work around it for now. */
2810 size
= int_size_in_bytes (TREE_TYPE (object
));
2812 TREE_TYPE (ctor
) = type
= TREE_TYPE (object
);
2815 /* Find the maximum alignment we can assume for the object. */
2816 /* ??? Make use of DECL_OFFSET_ALIGN. */
2817 if (DECL_P (object
))
2818 align
= DECL_ALIGN (object
);
2820 align
= TYPE_ALIGN (type
);
2822 if (size
> 0 && !can_move_by_pieces (size
, align
))
2824 tree
new = create_tmp_var_raw (type
, "C");
2826 gimple_add_tmp_var (new);
2827 TREE_STATIC (new) = 1;
2828 TREE_READONLY (new) = 1;
2829 DECL_INITIAL (new) = ctor
;
2830 if (align
> DECL_ALIGN (new))
2832 DECL_ALIGN (new) = align
;
2833 DECL_USER_ALIGN (new) = 1;
2835 walk_tree (&DECL_INITIAL (new), force_labels_r
, NULL
, NULL
);
2837 TREE_OPERAND (*expr_p
, 1) = new;
2839 /* This is no longer an assignment of a CONSTRUCTOR, but
2840 we still may have processing to do on the LHS. So
2841 pretend we didn't do anything here to let that happen. */
2842 return GS_UNHANDLED
;
2848 /* Zap the CONSTRUCTOR element list, which simplifies this case.
2849 Note that we still have to gimplify, in order to handle the
2850 case of variable sized types. Avoid shared tree structures. */
2851 CONSTRUCTOR_ELTS (ctor
) = NULL
;
2852 object
= unshare_expr (object
);
2853 gimplify_stmt (expr_p
);
2854 append_to_statement_list (*expr_p
, pre_p
);
2857 /* If we have not block cleared the object, or if there are nonzero
2858 elements in the constructor, add assignments to the individual
2859 scalar fields of the object. */
2860 if (!cleared
|| num_nonzero_elements
> 0)
2862 preeval_data
.lhs_base_decl
= get_base_address (object
);
2863 if (!DECL_P (preeval_data
.lhs_base_decl
))
2864 preeval_data
.lhs_base_decl
= NULL
;
2865 preeval_data
.lhs_alias_set
= get_alias_set (object
);
2867 gimplify_init_ctor_preeval (&TREE_OPERAND (*expr_p
, 1),
2868 pre_p
, post_p
, &preeval_data
);
2869 gimplify_init_ctor_eval (object
, elts
, pre_p
, cleared
);
2872 *expr_p
= NULL_TREE
;
2880 /* Extract the real and imaginary parts out of the ctor. */
2881 gcc_assert (VEC_length (constructor_elt
, elts
) == 2);
2882 r
= VEC_index (constructor_elt
, elts
, 0)->value
;
2883 i
= VEC_index (constructor_elt
, elts
, 1)->value
;
2884 if (r
== NULL
|| i
== NULL
)
2886 tree zero
= convert (TREE_TYPE (type
), integer_zero_node
);
2893 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
2894 represent creation of a complex value. */
2895 if (TREE_CONSTANT (r
) && TREE_CONSTANT (i
))
2897 ctor
= build_complex (type
, r
, i
);
2898 TREE_OPERAND (*expr_p
, 1) = ctor
;
2902 ctor
= build (COMPLEX_EXPR
, type
, r
, i
);
2903 TREE_OPERAND (*expr_p
, 1) = ctor
;
2904 ret
= gimplify_expr (&TREE_OPERAND (*expr_p
, 1), pre_p
, post_p
,
2905 rhs_predicate_for (TREE_OPERAND (*expr_p
, 0)),
2913 unsigned HOST_WIDE_INT ix
;
2914 constructor_elt
*ce
;
2916 /* Go ahead and simplify constant constructors to VECTOR_CST. */
2917 if (TREE_CONSTANT (ctor
))
2919 bool constant_p
= true;
2922 /* Even when ctor is constant, it might contain non-*_CST
2923 elements (e.g. { 1.0/0.0 - 1.0/0.0, 0.0 }) and those don't
2924 belong into VECTOR_CST nodes. */
2925 FOR_EACH_CONSTRUCTOR_VALUE (elts
, ix
, value
)
2926 if (!CONSTANT_CLASS_P (value
))
2934 TREE_OPERAND (*expr_p
, 1) = build_vector_from_ctor (type
, elts
);
2939 /* Vector types use CONSTRUCTOR all the way through gimple
2940 compilation as a general initializer. */
2941 for (ix
= 0; VEC_iterate (constructor_elt
, elts
, ix
, ce
); ix
++)
2943 enum gimplify_status tret
;
2944 tret
= gimplify_expr (&ce
->value
, pre_p
, post_p
,
2945 is_gimple_val
, fb_rvalue
);
2946 if (tret
== GS_ERROR
)
2953 /* So how did we get a CONSTRUCTOR for a scalar type? */
2957 if (ret
== GS_ERROR
)
2959 else if (want_value
)
2961 append_to_statement_list (*expr_p
, pre_p
);
2969 /* Given a pointer value OP0, return a simplified version of an
2970 indirection through OP0, or NULL_TREE if no simplification is
2971 possible. This may only be applied to a rhs of an expression.
2972 Note that the resulting type may be different from the type pointed
2973 to in the sense that it is still compatible from the langhooks
2977 fold_indirect_ref_rhs (tree t
)
2979 tree type
= TREE_TYPE (TREE_TYPE (t
));
2984 subtype
= TREE_TYPE (sub
);
2985 if (!POINTER_TYPE_P (subtype
))
2988 if (TREE_CODE (sub
) == ADDR_EXPR
)
2990 tree op
= TREE_OPERAND (sub
, 0);
2991 tree optype
= TREE_TYPE (op
);
2993 if (lang_hooks
.types_compatible_p (type
, optype
))
2995 /* *(foo *)&fooarray => fooarray[0] */
2996 else if (TREE_CODE (optype
) == ARRAY_TYPE
2997 && lang_hooks
.types_compatible_p (type
, TREE_TYPE (optype
)))
2999 tree type_domain
= TYPE_DOMAIN (optype
);
3000 tree min_val
= size_zero_node
;
3001 if (type_domain
&& TYPE_MIN_VALUE (type_domain
))
3002 min_val
= TYPE_MIN_VALUE (type_domain
);
3003 return build4 (ARRAY_REF
, type
, op
, min_val
, NULL_TREE
, NULL_TREE
);
3007 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
3008 if (TREE_CODE (TREE_TYPE (subtype
)) == ARRAY_TYPE
3009 && lang_hooks
.types_compatible_p (type
, TREE_TYPE (TREE_TYPE (subtype
))))
3012 tree min_val
= size_zero_node
;
3014 sub
= fold_indirect_ref_rhs (sub
);
3016 sub
= build1 (INDIRECT_REF
, TREE_TYPE (subtype
), osub
);
3017 type_domain
= TYPE_DOMAIN (TREE_TYPE (sub
));
3018 if (type_domain
&& TYPE_MIN_VALUE (type_domain
))
3019 min_val
= TYPE_MIN_VALUE (type_domain
);
3020 return build4 (ARRAY_REF
, type
, sub
, min_val
, NULL_TREE
, NULL_TREE
);
3026 /* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs
3027 based on the code of the RHS. We loop for as long as something changes. */
3029 static enum gimplify_status
3030 gimplify_modify_expr_rhs (tree
*expr_p
, tree
*from_p
, tree
*to_p
, tree
*pre_p
,
3031 tree
*post_p
, bool want_value
)
3033 enum gimplify_status ret
= GS_OK
;
3035 while (ret
!= GS_UNHANDLED
)
3036 switch (TREE_CODE (*from_p
))
3040 /* If we have code like
3044 where the type of "x" is a (possibly cv-qualified variant
3045 of "A"), treat the entire expression as identical to "x".
3046 This kind of code arises in C++ when an object is bound
3047 to a const reference, and if "x" is a TARGET_EXPR we want
3048 to take advantage of the optimization below. */
3049 tree t
= fold_indirect_ref_rhs (TREE_OPERAND (*from_p
, 0));
3062 /* If we are initializing something from a TARGET_EXPR, strip the
3063 TARGET_EXPR and initialize it directly, if possible. This can't
3064 be done if the initializer is void, since that implies that the
3065 temporary is set in some non-trivial way.
3067 ??? What about code that pulls out the temp and uses it
3068 elsewhere? I think that such code never uses the TARGET_EXPR as
3069 an initializer. If I'm wrong, we'll die because the temp won't
3070 have any RTL. In that case, I guess we'll need to replace
3071 references somehow. */
3072 tree init
= TARGET_EXPR_INITIAL (*from_p
);
3074 if (!VOID_TYPE_P (TREE_TYPE (init
)))
3085 /* Remove any COMPOUND_EXPR in the RHS so the following cases will be
3087 gimplify_compound_expr (from_p
, pre_p
, true);
3092 /* If we're initializing from a CONSTRUCTOR, break this into
3093 individual MODIFY_EXPRs. */
3094 return gimplify_init_constructor (expr_p
, pre_p
, post_p
, want_value
);
3097 /* If we're assigning to a non-register type, push the assignment
3098 down into the branches. This is mandatory for ADDRESSABLE types,
3099 since we cannot generate temporaries for such, but it saves a
3100 copy in other cases as well. */
3101 if (!is_gimple_reg_type (TREE_TYPE (*from_p
)))
3104 return gimplify_cond_expr (expr_p
, pre_p
, post_p
, *to_p
,
3112 /* For calls that return in memory, give *to_p as the CALL_EXPR's
3113 return slot so that we don't generate a temporary. */
3114 if (!CALL_EXPR_RETURN_SLOT_OPT (*from_p
)
3115 && aggregate_value_p (*from_p
, *from_p
))
3119 if (TREE_CODE (*to_p
) == RESULT_DECL
3120 && needs_to_live_in_memory (*to_p
))
3121 /* It's always OK to use the return slot directly. */
3123 else if (!is_gimple_non_addressable (*to_p
))
3124 /* Don't use the original target if it's already addressable;
3125 if its address escapes, and the called function uses the
3126 NRV optimization, a conforming program could see *to_p
3127 change before the called function returns; see c++/19317.
3128 When optimizing, the return_slot pass marks more functions
3129 as safe after we have escape info. */
3131 else if (TREE_CODE (*to_p
) != PARM_DECL
3132 && DECL_GIMPLE_FORMAL_TEMP_P (*to_p
))
3133 /* Don't use the original target if it's a formal temp; we
3134 don't want to take their addresses. */
3136 else if (is_gimple_reg_type (TREE_TYPE (*to_p
)))
3137 /* Also don't force regs into memory. */
3144 CALL_EXPR_RETURN_SLOT_OPT (*from_p
) = 1;
3145 lang_hooks
.mark_addressable (*to_p
);
3160 /* Promote partial stores to COMPLEX variables to total stores. *EXPR_P is
3161 a MODIFY_EXPR with a lhs of a REAL/IMAGPART_EXPR of a variable with
3162 DECL_COMPLEX_GIMPLE_REG_P set. */
3164 static enum gimplify_status
3165 gimplify_modify_expr_complex_part (tree
*expr_p
, tree
*pre_p
, bool want_value
)
3167 enum tree_code code
, ocode
;
3168 tree lhs
, rhs
, new_rhs
, other
, realpart
, imagpart
;
3170 lhs
= TREE_OPERAND (*expr_p
, 0);
3171 rhs
= TREE_OPERAND (*expr_p
, 1);
3172 code
= TREE_CODE (lhs
);
3173 lhs
= TREE_OPERAND (lhs
, 0);
3175 ocode
= code
== REALPART_EXPR
? IMAGPART_EXPR
: REALPART_EXPR
;
3176 other
= build1 (ocode
, TREE_TYPE (rhs
), lhs
);
3177 other
= get_formal_tmp_var (other
, pre_p
);
3179 realpart
= code
== REALPART_EXPR
? rhs
: other
;
3180 imagpart
= code
== REALPART_EXPR
? other
: rhs
;
3182 if (TREE_CONSTANT (realpart
) && TREE_CONSTANT (imagpart
))
3183 new_rhs
= build_complex (TREE_TYPE (lhs
), realpart
, imagpart
);
3185 new_rhs
= build2 (COMPLEX_EXPR
, TREE_TYPE (lhs
), realpart
, imagpart
);
3187 TREE_OPERAND (*expr_p
, 0) = lhs
;
3188 TREE_OPERAND (*expr_p
, 1) = new_rhs
;
3192 append_to_statement_list (*expr_p
, pre_p
);
3199 /* Gimplify the MODIFY_EXPR node pointed to by EXPR_P.
3205 PRE_P points to the list where side effects that must happen before
3206 *EXPR_P should be stored.
3208 POST_P points to the list where side effects that must happen after
3209 *EXPR_P should be stored.
3211 WANT_VALUE is nonzero iff we want to use the value of this expression
3212 in another expression. */
3214 static enum gimplify_status
3215 gimplify_modify_expr (tree
*expr_p
, tree
*pre_p
, tree
*post_p
, bool want_value
)
3217 tree
*from_p
= &TREE_OPERAND (*expr_p
, 1);
3218 tree
*to_p
= &TREE_OPERAND (*expr_p
, 0);
3219 enum gimplify_status ret
= GS_UNHANDLED
;
3221 gcc_assert (TREE_CODE (*expr_p
) == MODIFY_EXPR
3222 || TREE_CODE (*expr_p
) == INIT_EXPR
);
3224 /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer useful. */
3225 if (TREE_CODE (*expr_p
) == INIT_EXPR
)
3226 TREE_SET_CODE (*expr_p
, MODIFY_EXPR
);
3228 /* For zero sized types only gimplify the left hand side and right hand side
3229 as statements and throw away the assignment. */
3230 if (zero_sized_type (TREE_TYPE (*from_p
)))
3232 gimplify_stmt (from_p
);
3233 gimplify_stmt (to_p
);
3234 append_to_statement_list (*from_p
, pre_p
);
3235 append_to_statement_list (*to_p
, pre_p
);
3236 *expr_p
= NULL_TREE
;
3240 /* See if any simplifications can be done based on what the RHS is. */
3241 ret
= gimplify_modify_expr_rhs (expr_p
, from_p
, to_p
, pre_p
, post_p
,
3243 if (ret
!= GS_UNHANDLED
)
3246 /* If the value being copied is of variable width, compute the length
3247 of the copy into a WITH_SIZE_EXPR. Note that we need to do this
3248 before gimplifying any of the operands so that we can resolve any
3249 PLACEHOLDER_EXPRs in the size. Also note that the RTL expander uses
3250 the size of the expression to be copied, not of the destination, so
3251 that is what we must here. */
3252 maybe_with_size_expr (from_p
);
3254 ret
= gimplify_expr (to_p
, pre_p
, post_p
, is_gimple_lvalue
, fb_lvalue
);
3255 if (ret
== GS_ERROR
)
3258 ret
= gimplify_expr (from_p
, pre_p
, post_p
,
3259 rhs_predicate_for (*to_p
), fb_rvalue
);
3260 if (ret
== GS_ERROR
)
3263 /* Now see if the above changed *from_p to something we handle specially. */
3264 ret
= gimplify_modify_expr_rhs (expr_p
, from_p
, to_p
, pre_p
, post_p
,
3266 if (ret
!= GS_UNHANDLED
)
3269 /* If we've got a variable sized assignment between two lvalues (i.e. does
3270 not involve a call), then we can make things a bit more straightforward
3271 by converting the assignment to memcpy or memset. */
3272 if (TREE_CODE (*from_p
) == WITH_SIZE_EXPR
)
3274 tree from
= TREE_OPERAND (*from_p
, 0);
3275 tree size
= TREE_OPERAND (*from_p
, 1);
3277 if (TREE_CODE (from
) == CONSTRUCTOR
)
3278 return gimplify_modify_expr_to_memset (expr_p
, size
, want_value
);
3279 if (is_gimple_addressable (from
))
3282 return gimplify_modify_expr_to_memcpy (expr_p
, size
, want_value
);
3286 /* Transform partial stores to non-addressable complex variables into
3287 total stores. This allows us to use real instead of virtual operands
3288 for these variables, which improves optimization. */
3289 if ((TREE_CODE (*to_p
) == REALPART_EXPR
3290 || TREE_CODE (*to_p
) == IMAGPART_EXPR
)
3291 && is_gimple_reg (TREE_OPERAND (*to_p
, 0)))
3292 return gimplify_modify_expr_complex_part (expr_p
, pre_p
, want_value
);
3294 if (gimplify_ctxp
->into_ssa
&& is_gimple_reg (*to_p
))
3296 /* If we've somehow already got an SSA_NAME on the LHS, then
3297 we're probably modified it twice. Not good. */
3298 gcc_assert (TREE_CODE (*to_p
) != SSA_NAME
);
3299 *to_p
= make_ssa_name (*to_p
, *expr_p
);
3304 append_to_statement_list (*expr_p
, pre_p
);
3312 /* Gimplify a comparison between two variable-sized objects. Do this
3313 with a call to BUILT_IN_MEMCMP. */
3315 static enum gimplify_status
3316 gimplify_variable_sized_compare (tree
*expr_p
)
3318 tree op0
= TREE_OPERAND (*expr_p
, 0);
3319 tree op1
= TREE_OPERAND (*expr_p
, 1);
3322 t
= TYPE_SIZE_UNIT (TREE_TYPE (op0
));
3323 t
= unshare_expr (t
);
3324 t
= SUBSTITUTE_PLACEHOLDER_IN_EXPR (t
, op0
);
3325 args
= tree_cons (NULL
, t
, NULL
);
3326 t
= build_fold_addr_expr (op1
);
3327 args
= tree_cons (NULL
, t
, args
);
3328 dest
= build_fold_addr_expr (op0
);
3329 args
= tree_cons (NULL
, dest
, args
);
3330 t
= implicit_built_in_decls
[BUILT_IN_MEMCMP
];
3331 t
= build_function_call_expr (t
, args
);
3333 = build (TREE_CODE (*expr_p
), TREE_TYPE (*expr_p
), t
, integer_zero_node
);
3338 /* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P
3339 points to the expression to gimplify.
3341 Expressions of the form 'a && b' are gimplified to:
3343 a && b ? true : false
3345 gimplify_cond_expr will do the rest.
3347 PRE_P points to the list where side effects that must happen before
3348 *EXPR_P should be stored. */
3350 static enum gimplify_status
3351 gimplify_boolean_expr (tree
*expr_p
)
3353 /* Preserve the original type of the expression. */
3354 tree type
= TREE_TYPE (*expr_p
);
3356 *expr_p
= build (COND_EXPR
, type
, *expr_p
,
3357 convert (type
, boolean_true_node
),
3358 convert (type
, boolean_false_node
));
3363 /* Gimplifies an expression sequence. This function gimplifies each
3364 expression and re-writes the original expression with the last
3365 expression of the sequence in GIMPLE form.
3367 PRE_P points to the list where the side effects for all the
3368 expressions in the sequence will be emitted.
3370 WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */
3371 /* ??? Should rearrange to share the pre-queue with all the indirect
3372 invocations of gimplify_expr. Would probably save on creations
3373 of statement_list nodes. */
3375 static enum gimplify_status
3376 gimplify_compound_expr (tree
*expr_p
, tree
*pre_p
, bool want_value
)
3382 tree
*sub_p
= &TREE_OPERAND (t
, 0);
3384 if (TREE_CODE (*sub_p
) == COMPOUND_EXPR
)
3385 gimplify_compound_expr (sub_p
, pre_p
, false);
3387 gimplify_stmt (sub_p
);
3388 append_to_statement_list (*sub_p
, pre_p
);
3390 t
= TREE_OPERAND (t
, 1);
3392 while (TREE_CODE (t
) == COMPOUND_EXPR
);
3399 gimplify_stmt (expr_p
);
3404 /* Gimplifies a statement list. These may be created either by an
3405 enlightened front-end, or by shortcut_cond_expr. */
3407 static enum gimplify_status
3408 gimplify_statement_list (tree
*expr_p
)
3410 tree_stmt_iterator i
= tsi_start (*expr_p
);
3412 while (!tsi_end_p (i
))
3416 gimplify_stmt (tsi_stmt_ptr (i
));
3421 else if (TREE_CODE (t
) == STATEMENT_LIST
)
3423 tsi_link_before (&i
, t
, TSI_SAME_STMT
);
3433 /* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to
3434 gimplify. After gimplification, EXPR_P will point to a new temporary
3435 that holds the original value of the SAVE_EXPR node.
3437 PRE_P points to the list where side effects that must happen before
3438 *EXPR_P should be stored. */
3440 static enum gimplify_status
3441 gimplify_save_expr (tree
*expr_p
, tree
*pre_p
, tree
*post_p
)
3443 enum gimplify_status ret
= GS_ALL_DONE
;
3446 gcc_assert (TREE_CODE (*expr_p
) == SAVE_EXPR
);
3447 val
= TREE_OPERAND (*expr_p
, 0);
3449 /* If the SAVE_EXPR has not been resolved, then evaluate it once. */
3450 if (!SAVE_EXPR_RESOLVED_P (*expr_p
))
3452 /* The operand may be a void-valued expression such as SAVE_EXPRs
3453 generated by the Java frontend for class initialization. It is
3454 being executed only for its side-effects. */
3455 if (TREE_TYPE (val
) == void_type_node
)
3457 ret
= gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
, post_p
,
3458 is_gimple_stmt
, fb_none
);
3459 append_to_statement_list (TREE_OPERAND (*expr_p
, 0), pre_p
);
3463 val
= get_initialized_tmp_var (val
, pre_p
, post_p
);
3465 TREE_OPERAND (*expr_p
, 0) = val
;
3466 SAVE_EXPR_RESOLVED_P (*expr_p
) = 1;
3474 /* Re-write the ADDR_EXPR node pointed to by EXPR_P
3481 PRE_P points to the list where side effects that must happen before
3482 *EXPR_P should be stored.
3484 POST_P points to the list where side effects that must happen after
3485 *EXPR_P should be stored. */
3487 static enum gimplify_status
3488 gimplify_addr_expr (tree
*expr_p
, tree
*pre_p
, tree
*post_p
)
3490 tree expr
= *expr_p
;
3491 tree op0
= TREE_OPERAND (expr
, 0);
3492 enum gimplify_status ret
;
3494 switch (TREE_CODE (op0
))
3497 case MISALIGNED_INDIRECT_REF
:
3499 /* Check if we are dealing with an expression of the form '&*ptr'.
3500 While the front end folds away '&*ptr' into 'ptr', these
3501 expressions may be generated internally by the compiler (e.g.,
3502 builtins like __builtin_va_end). */
3503 /* Caution: the silent array decomposition semantics we allow for
3504 ADDR_EXPR means we can't always discard the pair. */
3505 /* Gimplification of the ADDR_EXPR operand may drop
3506 cv-qualification conversions, so make sure we add them if
3509 tree op00
= TREE_OPERAND (op0
, 0);
3510 tree t_expr
= TREE_TYPE (expr
);
3511 tree t_op00
= TREE_TYPE (op00
);
3513 if (!lang_hooks
.types_compatible_p (t_expr
, t_op00
))
3515 #ifdef ENABLE_CHECKING
3516 tree t_op0
= TREE_TYPE (op0
);
3517 gcc_assert (POINTER_TYPE_P (t_expr
)
3518 && cpt_same_type (TREE_CODE (t_op0
) == ARRAY_TYPE
3519 ? TREE_TYPE (t_op0
) : t_op0
,
3521 && POINTER_TYPE_P (t_op00
)
3522 && cpt_same_type (t_op0
, TREE_TYPE (t_op00
)));
3524 op00
= fold_convert (TREE_TYPE (expr
), op00
);
3531 case VIEW_CONVERT_EXPR
:
3532 /* Take the address of our operand and then convert it to the type of
3535 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3536 all clear. The impact of this transformation is even less clear. */
3538 /* If the operand is a useless conversion, look through it. Doing so
3539 guarantees that the ADDR_EXPR and its operand will remain of the
3541 if (tree_ssa_useless_type_conversion (TREE_OPERAND (op0
, 0)))
3542 op0
= TREE_OPERAND (op0
, 0);
3544 *expr_p
= fold_convert (TREE_TYPE (expr
),
3545 build_fold_addr_expr (TREE_OPERAND (op0
, 0)));
3550 /* We use fb_either here because the C frontend sometimes takes
3551 the address of a call that returns a struct; see
3552 gcc.dg/c99-array-lval-1.c. The gimplifier will correctly make
3553 the implied temporary explicit. */
3554 ret
= gimplify_expr (&TREE_OPERAND (expr
, 0), pre_p
, post_p
,
3555 is_gimple_addressable
, fb_either
);
3556 if (ret
!= GS_ERROR
)
3558 op0
= TREE_OPERAND (expr
, 0);
3560 /* For various reasons, the gimplification of the expression
3561 may have made a new INDIRECT_REF. */
3562 if (TREE_CODE (op0
) == INDIRECT_REF
)
3563 goto do_indirect_ref
;
3565 /* Make sure TREE_INVARIANT, TREE_CONSTANT, and TREE_SIDE_EFFECTS
3567 recompute_tree_invarant_for_addr_expr (expr
);
3569 /* Mark the RHS addressable. */
3570 lang_hooks
.mark_addressable (TREE_OPERAND (expr
, 0));
3578 /* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple
3579 value; output operands should be a gimple lvalue. */
3581 static enum gimplify_status
3582 gimplify_asm_expr (tree
*expr_p
, tree
*pre_p
, tree
*post_p
)
3584 tree expr
= *expr_p
;
3585 int noutputs
= list_length (ASM_OUTPUTS (expr
));
3586 const char **oconstraints
3587 = (const char **) alloca ((noutputs
) * sizeof (const char *));
3590 const char *constraint
;
3591 bool allows_mem
, allows_reg
, is_inout
;
3592 enum gimplify_status ret
, tret
;
3595 for (i
= 0, link
= ASM_OUTPUTS (expr
); link
; ++i
, link
= TREE_CHAIN (link
))
3597 size_t constraint_len
;
3598 oconstraints
[i
] = constraint
3599 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link
)));
3600 constraint_len
= strlen (constraint
);
3601 if (constraint_len
== 0)
3604 parse_output_constraint (&constraint
, i
, 0, 0,
3605 &allows_mem
, &allows_reg
, &is_inout
);
3607 if (TYPE_READONLY (TREE_TYPE (TREE_VALUE (link
))))
3609 error ("invalid lvalue in asm output %d", i
);
3613 if (!allows_reg
&& allows_mem
)
3614 lang_hooks
.mark_addressable (TREE_VALUE (link
));
3616 tret
= gimplify_expr (&TREE_VALUE (link
), pre_p
, post_p
,
3617 is_inout
? is_gimple_min_lval
: is_gimple_lvalue
,
3618 fb_lvalue
| fb_mayfail
);
3619 if (tret
== GS_ERROR
)
3621 error ("invalid lvalue in asm output %d", i
);
3627 /* An input/output operand. To give the optimizers more
3628 flexibility, split it into separate input and output
3633 /* Turn the in/out constraint into an output constraint. */
3634 char *p
= xstrdup (constraint
);
3636 TREE_VALUE (TREE_PURPOSE (link
)) = build_string (constraint_len
, p
);
3638 /* And add a matching input constraint. */
3641 sprintf (buf
, "%d", i
);
3643 /* If there are multiple alternatives in the constraint,
3644 handle each of them individually. Those that allow register
3645 will be replaced with operand number, the others will stay
3647 if (strchr (p
, ',') != NULL
)
3649 size_t len
= 0, buflen
= strlen (buf
);
3650 char *beg
, *end
, *str
, *dst
;
3654 end
= strchr (beg
, ',');
3656 end
= strchr (beg
, '\0');
3657 if ((size_t) (end
- beg
) < buflen
)
3660 len
+= end
- beg
+ 1;
3668 for (beg
= p
+ 1, dst
= str
;;)
3671 bool mem_p
, reg_p
, inout_p
;
3673 end
= strchr (beg
, ',');
3678 parse_output_constraint (&tem
, i
, 0, 0,
3679 &mem_p
, ®_p
, &inout_p
);
3684 memcpy (dst
, buf
, buflen
);
3693 memcpy (dst
, beg
, len
);
3702 input
= build_string (dst
- str
, str
);
3705 input
= build_string (strlen (buf
), buf
);
3708 input
= build_string (constraint_len
- 1, constraint
+ 1);
3712 input
= build_tree_list (build_tree_list (NULL_TREE
, input
),
3713 unshare_expr (TREE_VALUE (link
)));
3714 ASM_INPUTS (expr
) = chainon (ASM_INPUTS (expr
), input
);
3718 for (link
= ASM_INPUTS (expr
); link
; ++i
, link
= TREE_CHAIN (link
))
3721 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link
)));
3722 parse_input_constraint (&constraint
, 0, 0, noutputs
, 0,
3723 oconstraints
, &allows_mem
, &allows_reg
);
3725 /* If the operand is a memory input, it should be an lvalue. */
3726 if (!allows_reg
&& allows_mem
)
3728 lang_hooks
.mark_addressable (TREE_VALUE (link
));
3729 tret
= gimplify_expr (&TREE_VALUE (link
), pre_p
, post_p
,
3730 is_gimple_lvalue
, fb_lvalue
| fb_mayfail
);
3731 if (tret
== GS_ERROR
)
3733 error ("memory input %d is not directly addressable", i
);
3739 tret
= gimplify_expr (&TREE_VALUE (link
), pre_p
, post_p
,
3740 is_gimple_asm_val
, fb_rvalue
);
3741 if (tret
== GS_ERROR
)
3749 /* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding
3750 WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
3751 gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
3752 return to this function.
3754 FIXME should we complexify the prequeue handling instead? Or use flags
3755 for all the cleanups and let the optimizer tighten them up? The current
3756 code seems pretty fragile; it will break on a cleanup within any
3757 non-conditional nesting. But any such nesting would be broken, anyway;
3758 we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
3759 and continues out of it. We can do that at the RTL level, though, so
3760 having an optimizer to tighten up try/finally regions would be a Good
3763 static enum gimplify_status
3764 gimplify_cleanup_point_expr (tree
*expr_p
, tree
*pre_p
)
3766 tree_stmt_iterator iter
;
3769 tree temp
= voidify_wrapper_expr (*expr_p
, NULL
);
3771 /* We only care about the number of conditions between the innermost
3772 CLEANUP_POINT_EXPR and the cleanup. So save and reset the count. */
3773 int old_conds
= gimplify_ctxp
->conditions
;
3774 gimplify_ctxp
->conditions
= 0;
3776 body
= TREE_OPERAND (*expr_p
, 0);
3777 gimplify_to_stmt_list (&body
);
3779 gimplify_ctxp
->conditions
= old_conds
;
3781 for (iter
= tsi_start (body
); !tsi_end_p (iter
); )
3783 tree
*wce_p
= tsi_stmt_ptr (iter
);
3786 if (TREE_CODE (wce
) == WITH_CLEANUP_EXPR
)
3788 if (tsi_one_before_end_p (iter
))
3790 tsi_link_before (&iter
, TREE_OPERAND (wce
, 0), TSI_SAME_STMT
);
3797 enum tree_code code
;
3799 if (CLEANUP_EH_ONLY (wce
))
3800 code
= TRY_CATCH_EXPR
;
3802 code
= TRY_FINALLY_EXPR
;
3804 sl
= tsi_split_statement_list_after (&iter
);
3805 tfe
= build (code
, void_type_node
, sl
, NULL_TREE
);
3806 append_to_statement_list (TREE_OPERAND (wce
, 0),
3807 &TREE_OPERAND (tfe
, 1));
3809 iter
= tsi_start (sl
);
3819 append_to_statement_list (body
, pre_p
);
3829 /* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP
3830 is the cleanup action required. */
3833 gimple_push_cleanup (tree var
, tree cleanup
, bool eh_only
, tree
*pre_p
)
3837 /* Errors can result in improperly nested cleanups. Which results in
3838 confusion when trying to resolve the WITH_CLEANUP_EXPR. */
3839 if (errorcount
|| sorrycount
)
3842 if (gimple_conditional_context ())
3844 /* If we're in a conditional context, this is more complex. We only
3845 want to run the cleanup if we actually ran the initialization that
3846 necessitates it, but we want to run it after the end of the
3847 conditional context. So we wrap the try/finally around the
3848 condition and use a flag to determine whether or not to actually
3849 run the destructor. Thus
3853 becomes (approximately)
3857 if (test) { A::A(temp); flag = 1; val = f(temp); }
3860 if (flag) A::~A(temp);
3865 tree flag
= create_tmp_var (boolean_type_node
, "cleanup");
3866 tree ffalse
= build (MODIFY_EXPR
, void_type_node
, flag
,
3867 boolean_false_node
);
3868 tree ftrue
= build (MODIFY_EXPR
, void_type_node
, flag
,
3870 cleanup
= build (COND_EXPR
, void_type_node
, flag
, cleanup
, NULL
);
3871 wce
= build (WITH_CLEANUP_EXPR
, void_type_node
, cleanup
);
3872 append_to_statement_list (ffalse
, &gimplify_ctxp
->conditional_cleanups
);
3873 append_to_statement_list (wce
, &gimplify_ctxp
->conditional_cleanups
);
3874 append_to_statement_list (ftrue
, pre_p
);
3876 /* Because of this manipulation, and the EH edges that jump
3877 threading cannot redirect, the temporary (VAR) will appear
3878 to be used uninitialized. Don't warn. */
3879 TREE_NO_WARNING (var
) = 1;
3883 wce
= build (WITH_CLEANUP_EXPR
, void_type_node
, cleanup
);
3884 CLEANUP_EH_ONLY (wce
) = eh_only
;
3885 append_to_statement_list (wce
, pre_p
);
3888 gimplify_stmt (&TREE_OPERAND (wce
, 0));
3891 /* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */
3893 static enum gimplify_status
3894 gimplify_target_expr (tree
*expr_p
, tree
*pre_p
, tree
*post_p
)
3896 tree targ
= *expr_p
;
3897 tree temp
= TARGET_EXPR_SLOT (targ
);
3898 tree init
= TARGET_EXPR_INITIAL (targ
);
3899 enum gimplify_status ret
;
3903 /* TARGET_EXPR temps aren't part of the enclosing block, so add it
3904 to the temps list. */
3905 gimple_add_tmp_var (temp
);
3907 /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
3908 expression is supposed to initialize the slot. */
3909 if (VOID_TYPE_P (TREE_TYPE (init
)))
3910 ret
= gimplify_expr (&init
, pre_p
, post_p
, is_gimple_stmt
, fb_none
);
3913 /* Special handling for BIND_EXPR can result in fewer temps. */
3915 if (TREE_CODE (init
) == BIND_EXPR
)
3916 gimplify_bind_expr (&init
, temp
, pre_p
);
3919 init
= build (MODIFY_EXPR
, void_type_node
, temp
, init
);
3920 ret
= gimplify_expr (&init
, pre_p
, post_p
, is_gimple_stmt
,
3924 if (ret
== GS_ERROR
)
3926 append_to_statement_list (init
, pre_p
);
3928 /* If needed, push the cleanup for the temp. */
3929 if (TARGET_EXPR_CLEANUP (targ
))
3931 gimplify_stmt (&TARGET_EXPR_CLEANUP (targ
));
3932 gimple_push_cleanup (temp
, TARGET_EXPR_CLEANUP (targ
),
3933 CLEANUP_EH_ONLY (targ
), pre_p
);
3936 /* Only expand this once. */
3937 TREE_OPERAND (targ
, 3) = init
;
3938 TARGET_EXPR_INITIAL (targ
) = NULL_TREE
;
3941 /* We should have expanded this before. */
3942 gcc_assert (DECL_SEEN_IN_BIND_EXPR_P (temp
));
3948 /* Gimplification of expression trees. */
3950 /* Gimplify an expression which appears at statement context; usually, this
3951 means replacing it with a suitably gimple STATEMENT_LIST. */
3954 gimplify_stmt (tree
*stmt_p
)
3956 gimplify_expr (stmt_p
, NULL
, NULL
, is_gimple_stmt
, fb_none
);
3959 /* Similarly, but force the result to be a STATEMENT_LIST. */
3962 gimplify_to_stmt_list (tree
*stmt_p
)
3964 gimplify_stmt (stmt_p
);
3966 *stmt_p
= alloc_stmt_list ();
3967 else if (TREE_CODE (*stmt_p
) != STATEMENT_LIST
)
3970 *stmt_p
= alloc_stmt_list ();
3971 append_to_statement_list (t
, stmt_p
);
3976 /* Gimplifies the expression tree pointed to by EXPR_P. Return 0 if
3977 gimplification failed.
3979 PRE_P points to the list where side effects that must happen before
3980 EXPR should be stored.
3982 POST_P points to the list where side effects that must happen after
3983 EXPR should be stored, or NULL if there is no suitable list. In
3984 that case, we copy the result to a temporary, emit the
3985 post-effects, and then return the temporary.
3987 GIMPLE_TEST_F points to a function that takes a tree T and
3988 returns nonzero if T is in the GIMPLE form requested by the
3989 caller. The GIMPLE predicates are in tree-gimple.c.
3991 This test is used twice. Before gimplification, the test is
3992 invoked to determine whether *EXPR_P is already gimple enough. If
3993 that fails, *EXPR_P is gimplified according to its code and
3994 GIMPLE_TEST_F is called again. If the test still fails, then a new
3995 temporary variable is created and assigned the value of the
3996 gimplified expression.
3998 FALLBACK tells the function what sort of a temporary we want. If the 1
3999 bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK.
4000 If both are set, either is OK, but an lvalue is preferable.
4002 The return value is either GS_ERROR or GS_ALL_DONE, since this function
4003 iterates until solution. */
4005 enum gimplify_status
4006 gimplify_expr (tree
*expr_p
, tree
*pre_p
, tree
*post_p
,
4007 bool (* gimple_test_f
) (tree
), fallback_t fallback
)
4010 tree internal_pre
= NULL_TREE
;
4011 tree internal_post
= NULL_TREE
;
4013 int is_statement
= (pre_p
== NULL
);
4014 location_t saved_location
;
4015 enum gimplify_status ret
;
4017 save_expr
= *expr_p
;
4018 if (save_expr
== NULL_TREE
)
4021 /* We used to check the predicate here and return immediately if it
4022 succeeds. This is wrong; the design is for gimplification to be
4023 idempotent, and for the predicates to only test for valid forms, not
4024 whether they are fully simplified. */
4026 /* Set up our internal queues if needed. */
4028 pre_p
= &internal_pre
;
4030 post_p
= &internal_post
;
4032 saved_location
= input_location
;
4033 if (save_expr
!= error_mark_node
4034 && EXPR_HAS_LOCATION (*expr_p
))
4035 input_location
= EXPR_LOCATION (*expr_p
);
4037 /* Loop over the specific gimplifiers until the toplevel node
4038 remains the same. */
4041 /* Strip away as many useless type conversions as possible
4043 STRIP_USELESS_TYPE_CONVERSION (*expr_p
);
4045 /* Remember the expr. */
4046 save_expr
= *expr_p
;
4048 /* Die, die, die, my darling. */
4049 if (save_expr
== error_mark_node
4050 || (TREE_TYPE (save_expr
)
4051 && TREE_TYPE (save_expr
) == error_mark_node
))
4057 /* Do any language-specific gimplification. */
4058 ret
= lang_hooks
.gimplify_expr (expr_p
, pre_p
, post_p
);
4061 if (*expr_p
== NULL_TREE
)
4063 if (*expr_p
!= save_expr
)
4066 else if (ret
!= GS_UNHANDLED
)
4070 switch (TREE_CODE (*expr_p
))
4072 /* First deal with the special cases. */
4074 case POSTINCREMENT_EXPR
:
4075 case POSTDECREMENT_EXPR
:
4076 case PREINCREMENT_EXPR
:
4077 case PREDECREMENT_EXPR
:
4078 ret
= gimplify_self_mod_expr (expr_p
, pre_p
, post_p
,
4079 fallback
!= fb_none
);
4083 case ARRAY_RANGE_REF
:
4087 case VIEW_CONVERT_EXPR
:
4088 ret
= gimplify_compound_lval (expr_p
, pre_p
, post_p
,
4089 fallback
? fallback
: fb_rvalue
);
4093 ret
= gimplify_cond_expr (expr_p
, pre_p
, post_p
, NULL_TREE
,
4095 /* C99 code may assign to an array in a structure value of a
4096 conditional expression, and this has undefined behavior
4097 only on execution, so create a temporary if an lvalue is
4099 if (fallback
== fb_lvalue
)
4101 *expr_p
= get_initialized_tmp_var (*expr_p
, pre_p
, post_p
);
4102 lang_hooks
.mark_addressable (*expr_p
);
4107 ret
= gimplify_call_expr (expr_p
, pre_p
, fallback
!= fb_none
);
4108 /* C99 code may assign to an array in a structure returned
4109 from a function, and this has undefined behavior only on
4110 execution, so create a temporary if an lvalue is
4112 if (fallback
== fb_lvalue
)
4114 *expr_p
= get_initialized_tmp_var (*expr_p
, pre_p
, post_p
);
4115 lang_hooks
.mark_addressable (*expr_p
);
4123 ret
= gimplify_compound_expr (expr_p
, pre_p
, fallback
!= fb_none
);
4128 ret
= gimplify_modify_expr (expr_p
, pre_p
, post_p
,
4129 fallback
!= fb_none
);
4132 case TRUTH_ANDIF_EXPR
:
4133 case TRUTH_ORIF_EXPR
:
4134 ret
= gimplify_boolean_expr (expr_p
);
4137 case TRUTH_NOT_EXPR
:
4138 TREE_OPERAND (*expr_p
, 0)
4139 = gimple_boolify (TREE_OPERAND (*expr_p
, 0));
4140 ret
= gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
, post_p
,
4141 is_gimple_val
, fb_rvalue
);
4142 recalculate_side_effects (*expr_p
);
4146 ret
= gimplify_addr_expr (expr_p
, pre_p
, post_p
);
4150 ret
= gimplify_va_arg_expr (expr_p
, pre_p
, post_p
);
4155 if (IS_EMPTY_STMT (*expr_p
))
4161 if (VOID_TYPE_P (TREE_TYPE (*expr_p
))
4162 || fallback
== fb_none
)
4164 /* Just strip a conversion to void (or in void context) and
4166 *expr_p
= TREE_OPERAND (*expr_p
, 0);
4170 ret
= gimplify_conversion (expr_p
);
4171 if (ret
== GS_ERROR
)
4173 if (*expr_p
!= save_expr
)
4177 case FIX_TRUNC_EXPR
:
4179 case FIX_FLOOR_EXPR
:
4180 case FIX_ROUND_EXPR
:
4181 /* unary_expr: ... | '(' cast ')' val | ... */
4182 ret
= gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
, post_p
,
4183 is_gimple_val
, fb_rvalue
);
4184 recalculate_side_effects (*expr_p
);
4188 *expr_p
= fold_indirect_ref (*expr_p
);
4189 if (*expr_p
!= save_expr
)
4191 /* else fall through. */
4192 case ALIGN_INDIRECT_REF
:
4193 case MISALIGNED_INDIRECT_REF
:
4194 ret
= gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
, post_p
,
4195 is_gimple_reg
, fb_rvalue
);
4196 recalculate_side_effects (*expr_p
);
4199 /* Constants need not be gimplified. */
4209 /* If we require an lvalue, such as for ADDR_EXPR, retain the
4210 CONST_DECL node. Otherwise the decl is replaceable by its
4212 /* ??? Should be == fb_lvalue, but ADDR_EXPR passes fb_either. */
4213 if (fallback
& fb_lvalue
)
4216 *expr_p
= DECL_INITIAL (*expr_p
);
4220 ret
= gimplify_decl_expr (expr_p
);
4224 /* FIXME make this a decl. */
4229 ret
= gimplify_bind_expr (expr_p
, NULL
, pre_p
);
4233 ret
= gimplify_loop_expr (expr_p
, pre_p
);
4237 ret
= gimplify_switch_expr (expr_p
, pre_p
);
4241 ret
= gimplify_exit_expr (expr_p
);
4245 /* If the target is not LABEL, then it is a computed jump
4246 and the target needs to be gimplified. */
4247 if (TREE_CODE (GOTO_DESTINATION (*expr_p
)) != LABEL_DECL
)
4248 ret
= gimplify_expr (&GOTO_DESTINATION (*expr_p
), pre_p
,
4249 NULL
, is_gimple_val
, fb_rvalue
);
4254 gcc_assert (decl_function_context (LABEL_EXPR_LABEL (*expr_p
))
4255 == current_function_decl
);
4258 case CASE_LABEL_EXPR
:
4259 ret
= gimplify_case_label_expr (expr_p
);
4263 ret
= gimplify_return_expr (*expr_p
, pre_p
);
4267 /* Don't reduce this in place; let gimplify_init_constructor work its
4268 magic. Buf if we're just elaborating this for side effects, just
4269 gimplify any element that has side-effects. */
4270 if (fallback
== fb_none
)
4272 unsigned HOST_WIDE_INT ix
;
4273 constructor_elt
*ce
;
4275 VEC_iterate (constructor_elt
, CONSTRUCTOR_ELTS (*expr_p
),
4278 if (TREE_SIDE_EFFECTS (ce
->value
))
4279 gimplify_expr (&ce
->value
, pre_p
, post_p
,
4280 gimple_test_f
, fallback
);
4282 *expr_p
= NULL_TREE
;
4288 /* The following are special cases that are not handled by the
4289 original GIMPLE grammar. */
4291 /* SAVE_EXPR nodes are converted into a GIMPLE identifier and
4294 ret
= gimplify_save_expr (expr_p
, pre_p
, post_p
);
4299 enum gimplify_status r0
, r1
, r2
;
4301 r0
= gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
, post_p
,
4302 is_gimple_lvalue
, fb_either
);
4303 r1
= gimplify_expr (&TREE_OPERAND (*expr_p
, 1), pre_p
, post_p
,
4304 is_gimple_val
, fb_rvalue
);
4305 r2
= gimplify_expr (&TREE_OPERAND (*expr_p
, 2), pre_p
, post_p
,
4306 is_gimple_val
, fb_rvalue
);
4307 recalculate_side_effects (*expr_p
);
4309 ret
= MIN (r0
, MIN (r1
, r2
));
4313 case NON_LVALUE_EXPR
:
4314 /* This should have been stripped above. */
4318 ret
= gimplify_asm_expr (expr_p
, pre_p
, post_p
);
4321 case TRY_FINALLY_EXPR
:
4322 case TRY_CATCH_EXPR
:
4323 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p
, 0));
4324 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p
, 1));
4328 case CLEANUP_POINT_EXPR
:
4329 ret
= gimplify_cleanup_point_expr (expr_p
, pre_p
);
4333 ret
= gimplify_target_expr (expr_p
, pre_p
, post_p
);
4337 gimplify_to_stmt_list (&CATCH_BODY (*expr_p
));
4341 case EH_FILTER_EXPR
:
4342 gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p
));
4348 enum gimplify_status r0
, r1
;
4349 r0
= gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p
), pre_p
, post_p
,
4350 is_gimple_val
, fb_rvalue
);
4351 r1
= gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p
), pre_p
, post_p
,
4352 is_gimple_val
, fb_rvalue
);
4358 /* We get here when taking the address of a label. We mark
4359 the label as "forced"; meaning it can never be removed and
4360 it is a potential target for any computed goto. */
4361 FORCED_LABEL (*expr_p
) = 1;
4365 case STATEMENT_LIST
:
4366 ret
= gimplify_statement_list (expr_p
);
4369 case WITH_SIZE_EXPR
:
4371 gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
,
4372 post_p
== &internal_post
? NULL
: post_p
,
4373 gimple_test_f
, fallback
);
4374 gimplify_expr (&TREE_OPERAND (*expr_p
, 1), pre_p
, post_p
,
4375 is_gimple_val
, fb_rvalue
);
4380 /* ??? If this is a local variable, and it has not been seen in any
4381 outer BIND_EXPR, then it's probably the result of a duplicate
4382 declaration, for which we've already issued an error. It would
4383 be really nice if the front end wouldn't leak these at all.
4384 Currently the only known culprit is C++ destructors, as seen
4385 in g++.old-deja/g++.jason/binding.C. */
4387 if (!TREE_STATIC (tmp
) && !DECL_EXTERNAL (tmp
)
4388 && decl_function_context (tmp
) == current_function_decl
4389 && !DECL_SEEN_IN_BIND_EXPR_P (tmp
))
4391 gcc_assert (errorcount
|| sorrycount
);
4400 /* If this is a local variable sized decl, it must be accessed
4401 indirectly. Perform that substitution. */
4402 if (DECL_HAS_VALUE_EXPR_P (tmp
))
4404 *expr_p
= unshare_expr (DECL_VALUE_EXPR (tmp
));
4413 /* Allow callbacks into the gimplifier during optimization. */
4418 switch (TREE_CODE_CLASS (TREE_CODE (*expr_p
)))
4420 case tcc_comparison
:
4421 /* If this is a comparison of objects of aggregate type,
4422 handle it specially (by converting to a call to
4423 memcmp). It would be nice to only have to do this
4424 for variable-sized objects, but then we'd have to
4425 allow the same nest of reference nodes we allow for
4426 MODIFY_EXPR and that's too complex. */
4427 if (!AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p
, 1))))
4429 ret
= gimplify_variable_sized_compare (expr_p
);
4432 /* If *EXPR_P does not need to be special-cased, handle it
4433 according to its class. */
4435 ret
= gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
,
4436 post_p
, is_gimple_val
, fb_rvalue
);
4442 enum gimplify_status r0
, r1
;
4444 r0
= gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
,
4445 post_p
, is_gimple_val
, fb_rvalue
);
4446 r1
= gimplify_expr (&TREE_OPERAND (*expr_p
, 1), pre_p
,
4447 post_p
, is_gimple_val
, fb_rvalue
);
4453 case tcc_declaration
:
4456 goto dont_recalculate
;
4459 gcc_assert (TREE_CODE (*expr_p
) == TRUTH_AND_EXPR
4460 || TREE_CODE (*expr_p
) == TRUTH_OR_EXPR
4461 || TREE_CODE (*expr_p
) == TRUTH_XOR_EXPR
);
4465 recalculate_side_effects (*expr_p
);
4470 /* If we replaced *expr_p, gimplify again. */
4471 if (ret
== GS_OK
&& (*expr_p
== NULL
|| *expr_p
== save_expr
))
4474 while (ret
== GS_OK
);
4476 /* If we encountered an error_mark somewhere nested inside, either
4477 stub out the statement or propagate the error back out. */
4478 if (ret
== GS_ERROR
)
4485 /* This was only valid as a return value from the langhook, which
4486 we handled. Make sure it doesn't escape from any other context. */
4487 gcc_assert (ret
!= GS_UNHANDLED
);
4489 if (fallback
== fb_none
&& *expr_p
&& !is_gimple_stmt (*expr_p
))
4491 /* We aren't looking for a value, and we don't have a valid
4492 statement. If it doesn't have side-effects, throw it away. */
4493 if (!TREE_SIDE_EFFECTS (*expr_p
))
4495 else if (!TREE_THIS_VOLATILE (*expr_p
))
4497 /* This is probably a _REF that contains something nested that
4498 has side effects. Recurse through the operands to find it. */
4499 enum tree_code code
= TREE_CODE (*expr_p
);
4504 case REALPART_EXPR
: case IMAGPART_EXPR
:
4505 gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
, post_p
,
4506 gimple_test_f
, fallback
);
4509 case ARRAY_REF
: case ARRAY_RANGE_REF
:
4510 gimplify_expr (&TREE_OPERAND (*expr_p
, 0), pre_p
, post_p
,
4511 gimple_test_f
, fallback
);
4512 gimplify_expr (&TREE_OPERAND (*expr_p
, 1), pre_p
, post_p
,
4513 gimple_test_f
, fallback
);
4517 /* Anything else with side-effects must be converted to
4518 a valid statement before we get here. */
4524 else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p
)))
4526 /* Historically, the compiler has treated a bare
4527 reference to a volatile lvalue as forcing a load. */
4528 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (*expr_p
));
4529 /* Normally, we do want to create a temporary for a
4530 TREE_ADDRESSABLE type because such a type should not be
4531 copied by bitwise-assignment. However, we make an
4532 exception here, as all we are doing here is ensuring that
4533 we read the bytes that make up the type. We use
4534 create_tmp_var_raw because create_tmp_var will abort when
4535 given a TREE_ADDRESSABLE type. */
4536 tree tmp
= create_tmp_var_raw (type
, "vol");
4537 gimple_add_tmp_var (tmp
);
4538 *expr_p
= build (MODIFY_EXPR
, type
, tmp
, *expr_p
);
4541 /* We can't do anything useful with a volatile reference to
4542 incomplete type, so just throw it away. */
4546 /* If we are gimplifying at the statement level, we're done. Tack
4547 everything together and replace the original statement with the
4549 if (fallback
== fb_none
|| is_statement
)
4551 if (internal_pre
|| internal_post
)
4553 append_to_statement_list (*expr_p
, &internal_pre
);
4554 append_to_statement_list (internal_post
, &internal_pre
);
4555 annotate_all_with_locus (&internal_pre
, input_location
);
4556 *expr_p
= internal_pre
;
4560 else if (TREE_CODE (*expr_p
) == STATEMENT_LIST
)
4561 annotate_all_with_locus (expr_p
, input_location
);
4563 annotate_one_with_locus (*expr_p
, input_location
);
4567 /* Otherwise we're gimplifying a subexpression, so the resulting value is
4570 /* If it's sufficiently simple already, we're done. Unless we are
4571 handling some post-effects internally; if that's the case, we need to
4572 copy into a temp before adding the post-effects to the tree. */
4573 if (!internal_post
&& (*gimple_test_f
) (*expr_p
))
4576 /* Otherwise, we need to create a new temporary for the gimplified
4579 /* We can't return an lvalue if we have an internal postqueue. The
4580 object the lvalue refers to would (probably) be modified by the
4581 postqueue; we need to copy the value out first, which means an
4583 if ((fallback
& fb_lvalue
) && !internal_post
4584 && is_gimple_addressable (*expr_p
))
4586 /* An lvalue will do. Take the address of the expression, store it
4587 in a temporary, and replace the expression with an INDIRECT_REF of
4589 tmp
= build_fold_addr_expr (*expr_p
);
4590 gimplify_expr (&tmp
, pre_p
, post_p
, is_gimple_reg
, fb_rvalue
);
4591 *expr_p
= build1 (INDIRECT_REF
, TREE_TYPE (TREE_TYPE (tmp
)), tmp
);
4593 else if ((fallback
& fb_rvalue
) && is_gimple_formal_tmp_rhs (*expr_p
))
4595 gcc_assert (!VOID_TYPE_P (TREE_TYPE (*expr_p
)));
4597 /* An rvalue will do. Assign the gimplified expression into a new
4598 temporary TMP and replace the original expression with TMP. */
4600 if (internal_post
|| (fallback
& fb_lvalue
))
4601 /* The postqueue might change the value of the expression between
4602 the initialization and use of the temporary, so we can't use a
4603 formal temp. FIXME do we care? */
4604 *expr_p
= get_initialized_tmp_var (*expr_p
, pre_p
, post_p
);
4606 *expr_p
= get_formal_tmp_var (*expr_p
, pre_p
);
4608 if (TREE_CODE (*expr_p
) != SSA_NAME
)
4609 DECL_GIMPLE_FORMAL_TEMP_P (*expr_p
) = 1;
4613 #ifdef ENABLE_CHECKING
4614 if (!(fallback
& fb_mayfail
))
4616 fprintf (stderr
, "gimplification failed:\n");
4617 print_generic_expr (stderr
, *expr_p
, 0);
4618 debug_tree (*expr_p
);
4619 internal_error ("gimplification failed");
4622 gcc_assert (fallback
& fb_mayfail
);
4623 /* If this is an asm statement, and the user asked for the
4624 impossible, don't die. Fail and let gimplify_asm_expr
4630 /* Make sure the temporary matches our predicate. */
4631 gcc_assert ((*gimple_test_f
) (*expr_p
));
4635 annotate_all_with_locus (&internal_post
, input_location
);
4636 append_to_statement_list (internal_post
, pre_p
);
4640 input_location
= saved_location
;
4644 /* Look through TYPE for variable-sized objects and gimplify each such
4645 size that we find. Add to LIST_P any statements generated. */
4648 gimplify_type_sizes (tree type
, tree
*list_p
)
4652 if (type
== NULL
|| type
== error_mark_node
)
4655 /* We first do the main variant, then copy into any other variants. */
4656 type
= TYPE_MAIN_VARIANT (type
);
4658 /* Avoid infinite recursion. */
4659 if (TYPE_SIZES_GIMPLIFIED (type
))
4662 TYPE_SIZES_GIMPLIFIED (type
) = 1;
4664 switch (TREE_CODE (type
))
4671 gimplify_one_sizepos (&TYPE_MIN_VALUE (type
), list_p
);
4672 gimplify_one_sizepos (&TYPE_MAX_VALUE (type
), list_p
);
4674 for (t
= TYPE_NEXT_VARIANT (type
); t
; t
= TYPE_NEXT_VARIANT (t
))
4676 TYPE_MIN_VALUE (t
) = TYPE_MIN_VALUE (type
);
4677 TYPE_MAX_VALUE (t
) = TYPE_MAX_VALUE (type
);
4682 /* These types may not have declarations, so handle them here. */
4683 gimplify_type_sizes (TREE_TYPE (type
), list_p
);
4684 gimplify_type_sizes (TYPE_DOMAIN (type
), list_p
);
4689 case QUAL_UNION_TYPE
:
4690 for (field
= TYPE_FIELDS (type
); field
; field
= TREE_CHAIN (field
))
4691 if (TREE_CODE (field
) == FIELD_DECL
)
4693 gimplify_one_sizepos (&DECL_FIELD_OFFSET (field
), list_p
);
4694 gimplify_type_sizes (TREE_TYPE (field
), list_p
);
4699 case REFERENCE_TYPE
:
4700 gimplify_type_sizes (TREE_TYPE (type
), list_p
);
4707 gimplify_one_sizepos (&TYPE_SIZE (type
), list_p
);
4708 gimplify_one_sizepos (&TYPE_SIZE_UNIT (type
), list_p
);
4710 for (t
= TYPE_NEXT_VARIANT (type
); t
; t
= TYPE_NEXT_VARIANT (t
))
4712 TYPE_SIZE (t
) = TYPE_SIZE (type
);
4713 TYPE_SIZE_UNIT (t
) = TYPE_SIZE_UNIT (type
);
4714 TYPE_SIZES_GIMPLIFIED (t
) = 1;
4718 /* A subroutine of gimplify_type_sizes to make sure that *EXPR_P,
4719 a size or position, has had all of its SAVE_EXPRs evaluated.
4720 We add any required statements to STMT_P. */
4723 gimplify_one_sizepos (tree
*expr_p
, tree
*stmt_p
)
4725 tree type
, expr
= *expr_p
;
4727 /* We don't do anything if the value isn't there, is constant, or contains
4728 A PLACEHOLDER_EXPR. We also don't want to do anything if it's already
4729 a VAR_DECL. If it's a VAR_DECL from another function, the gimplifier
4730 will want to replace it with a new variable, but that will cause problems
4731 if this type is from outside the function. It's OK to have that here. */
4732 if (expr
== NULL_TREE
|| TREE_CONSTANT (expr
)
4733 || TREE_CODE (expr
) == VAR_DECL
4734 || CONTAINS_PLACEHOLDER_P (expr
))
4737 type
= TREE_TYPE (expr
);
4738 *expr_p
= unshare_expr (expr
);
4740 gimplify_expr (expr_p
, stmt_p
, NULL
, is_gimple_val
, fb_rvalue
);
4743 /* Verify that we've an exact type match with the original expression.
4744 In particular, we do not wish to drop a "sizetype" in favour of a
4745 type of similar dimensions. We don't want to pollute the generic
4746 type-stripping code with this knowledge because it doesn't matter
4747 for the bulk of GENERIC/GIMPLE. It only matters that TYPE_SIZE_UNIT
4748 and friends retain their "sizetype-ness". */
4749 if (TREE_TYPE (expr
) != type
4750 && TREE_CODE (type
) == INTEGER_TYPE
4751 && TYPE_IS_SIZETYPE (type
))
4755 *expr_p
= create_tmp_var (type
, NULL
);
4756 tmp
= build1 (NOP_EXPR
, type
, expr
);
4757 tmp
= build2 (MODIFY_EXPR
, type
, *expr_p
, expr
);
4758 if (EXPR_HAS_LOCATION (expr
))
4759 SET_EXPR_LOCUS (tmp
, EXPR_LOCUS (expr
));
4761 SET_EXPR_LOCATION (tmp
, input_location
);
4763 gimplify_and_add (tmp
, stmt_p
);
4767 #ifdef ENABLE_CHECKING
4768 /* Compare types A and B for a "close enough" match. */
4771 cpt_same_type (tree a
, tree b
)
4773 if (lang_hooks
.types_compatible_p (a
, b
))
4776 /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't
4777 link them together. This routine is intended to catch type errors
4778 that will affect the optimizers, and the optimizers don't add new
4779 dereferences of function pointers, so ignore it. */
4780 if ((TREE_CODE (a
) == FUNCTION_TYPE
|| TREE_CODE (a
) == METHOD_TYPE
)
4781 && (TREE_CODE (b
) == FUNCTION_TYPE
|| TREE_CODE (b
) == METHOD_TYPE
))
4784 /* ??? The C FE pushes type qualifiers after the fact into the type of
4785 the element from the type of the array. See build_unary_op's handling
4786 of ADDR_EXPR. This seems wrong -- if we were going to do this, we
4787 should have done it when creating the variable in the first place.
4788 Alternately, why aren't the two array types made variants? */
4789 if (TREE_CODE (a
) == ARRAY_TYPE
&& TREE_CODE (b
) == ARRAY_TYPE
)
4790 return cpt_same_type (TREE_TYPE (a
), TREE_TYPE (b
));
4792 /* And because of those, we have to recurse down through pointers. */
4793 if (POINTER_TYPE_P (a
) && POINTER_TYPE_P (b
))
4794 return cpt_same_type (TREE_TYPE (a
), TREE_TYPE (b
));
4799 /* Check for some cases of the front end missing cast expressions.
4800 The type of a dereference should correspond to the pointer type;
4801 similarly the type of an address should match its object. */
4804 check_pointer_types_r (tree
*tp
, int *walk_subtrees ATTRIBUTE_UNUSED
,
4805 void *data ATTRIBUTE_UNUSED
)
4808 tree ptype
, otype
, dtype
;
4810 switch (TREE_CODE (t
))
4814 otype
= TREE_TYPE (t
);
4815 ptype
= TREE_TYPE (TREE_OPERAND (t
, 0));
4816 dtype
= TREE_TYPE (ptype
);
4817 gcc_assert (cpt_same_type (otype
, dtype
));
4821 ptype
= TREE_TYPE (t
);
4822 otype
= TREE_TYPE (TREE_OPERAND (t
, 0));
4823 dtype
= TREE_TYPE (ptype
);
4824 if (!cpt_same_type (otype
, dtype
))
4826 /* &array is allowed to produce a pointer to the element, rather than
4827 a pointer to the array type. We must allow this in order to
4828 properly represent assigning the address of an array in C into
4829 pointer to the element type. */
4830 gcc_assert (TREE_CODE (otype
) == ARRAY_TYPE
4831 && POINTER_TYPE_P (ptype
)
4832 && cpt_same_type (TREE_TYPE (otype
), dtype
));
4846 /* Gimplify the body of statements pointed to by BODY_P. FNDECL is the
4847 function decl containing BODY. */
4850 gimplify_body (tree
*body_p
, tree fndecl
, bool do_parms
)
4852 location_t saved_location
= input_location
;
4853 tree body
, parm_stmts
;
4855 timevar_push (TV_TREE_GIMPLIFY
);
4856 push_gimplify_context ();
4858 /* Unshare most shared trees in the body and in that of any nested functions.
4859 It would seem we don't have to do this for nested functions because
4860 they are supposed to be output and then the outer function gimplified
4861 first, but the g++ front end doesn't always do it that way. */
4862 unshare_body (body_p
, fndecl
);
4863 unvisit_body (body_p
, fndecl
);
4865 /* Make sure input_location isn't set to something wierd. */
4866 input_location
= DECL_SOURCE_LOCATION (fndecl
);
4868 /* Resolve callee-copies. This has to be done before processing
4869 the body so that DECL_VALUE_EXPR gets processed correctly. */
4870 parm_stmts
= do_parms
? gimplify_parameters () : NULL
;
4872 /* Gimplify the function's body. */
4873 gimplify_stmt (body_p
);
4877 body
= alloc_stmt_list ();
4878 else if (TREE_CODE (body
) == STATEMENT_LIST
)
4880 tree t
= expr_only (*body_p
);
4885 /* If there isn't an outer BIND_EXPR, add one. */
4886 if (TREE_CODE (body
) != BIND_EXPR
)
4888 tree b
= build (BIND_EXPR
, void_type_node
, NULL_TREE
,
4889 NULL_TREE
, NULL_TREE
);
4890 TREE_SIDE_EFFECTS (b
) = 1;
4891 append_to_statement_list_force (body
, &BIND_EXPR_BODY (b
));
4895 /* If we had callee-copies statements, insert them at the beginning
4899 append_to_statement_list_force (BIND_EXPR_BODY (body
), &parm_stmts
);
4900 BIND_EXPR_BODY (body
) = parm_stmts
;
4903 /* Unshare again, in case gimplification was sloppy. */
4904 unshare_all_trees (body
);
4908 pop_gimplify_context (body
);
4910 #ifdef ENABLE_CHECKING
4911 walk_tree (body_p
, check_pointer_types_r
, NULL
, NULL
);
4914 timevar_pop (TV_TREE_GIMPLIFY
);
4915 input_location
= saved_location
;
4918 /* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL
4919 node for the function we want to gimplify. */
4922 gimplify_function_tree (tree fndecl
)
4924 tree oldfn
, parm
, ret
;
4926 oldfn
= current_function_decl
;
4927 current_function_decl
= fndecl
;
4928 cfun
= DECL_STRUCT_FUNCTION (fndecl
);
4930 allocate_struct_function (fndecl
);
4932 for (parm
= DECL_ARGUMENTS (fndecl
); parm
; parm
= TREE_CHAIN (parm
))
4934 /* Preliminarily mark non-addressed complex variables as eligible
4935 for promotion to gimple registers. We'll transform their uses
4937 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
4938 && !TREE_THIS_VOLATILE (parm
)
4939 && !needs_to_live_in_memory (parm
))
4940 DECL_COMPLEX_GIMPLE_REG_P (parm
) = 1;
4943 ret
= DECL_RESULT (fndecl
);
4944 if (TREE_CODE (TREE_TYPE (ret
)) == COMPLEX_TYPE
4945 && !needs_to_live_in_memory (ret
))
4946 DECL_COMPLEX_GIMPLE_REG_P (ret
) = 1;
4948 gimplify_body (&DECL_SAVED_TREE (fndecl
), fndecl
, true);
4950 /* If we're instrumenting function entry/exit, then prepend the call to
4951 the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
4952 catch the exit hook. */
4953 /* ??? Add some way to ignore exceptions for this TFE. */
4954 if (flag_instrument_function_entry_exit
4955 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl
))
4959 tf
= build (TRY_FINALLY_EXPR
, void_type_node
, NULL
, NULL
);
4960 TREE_SIDE_EFFECTS (tf
) = 1;
4961 x
= DECL_SAVED_TREE (fndecl
);
4962 append_to_statement_list (x
, &TREE_OPERAND (tf
, 0));
4963 x
= implicit_built_in_decls
[BUILT_IN_PROFILE_FUNC_EXIT
];
4964 x
= build_function_call_expr (x
, NULL
);
4965 append_to_statement_list (x
, &TREE_OPERAND (tf
, 1));
4967 bind
= build (BIND_EXPR
, void_type_node
, NULL
, NULL
, NULL
);
4968 TREE_SIDE_EFFECTS (bind
) = 1;
4969 x
= implicit_built_in_decls
[BUILT_IN_PROFILE_FUNC_ENTER
];
4970 x
= build_function_call_expr (x
, NULL
);
4971 append_to_statement_list (x
, &BIND_EXPR_BODY (bind
));
4972 append_to_statement_list (tf
, &BIND_EXPR_BODY (bind
));
4974 DECL_SAVED_TREE (fndecl
) = bind
;
4977 current_function_decl
= oldfn
;
4978 cfun
= oldfn
? DECL_STRUCT_FUNCTION (oldfn
) : NULL
;
4982 /* Expands EXPR to list of gimple statements STMTS. If SIMPLE is true,
4983 force the result to be either ssa_name or an invariant, otherwise
4984 just force it to be a rhs expression. If VAR is not NULL, make the
4985 base variable of the final destination be VAR if suitable. */
4988 force_gimple_operand (tree expr
, tree
*stmts
, bool simple
, tree var
)
4991 enum gimplify_status ret
;
4992 gimple_predicate gimple_test_f
;
4996 if (is_gimple_val (expr
))
4999 gimple_test_f
= simple
? is_gimple_val
: is_gimple_reg_rhs
;
5001 push_gimplify_context ();
5002 gimplify_ctxp
->into_ssa
= in_ssa_p
;
5005 expr
= build (MODIFY_EXPR
, TREE_TYPE (var
), var
, expr
);
5007 ret
= gimplify_expr (&expr
, stmts
, NULL
,
5008 gimple_test_f
, fb_rvalue
);
5009 gcc_assert (ret
!= GS_ERROR
);
5011 if (referenced_vars
)
5013 for (t
= gimplify_ctxp
->temps
; t
; t
= TREE_CHAIN (t
))
5014 add_referenced_tmp_var (t
);
5017 pop_gimplify_context (NULL
);
5022 /* Invokes force_gimple_operand for EXPR with parameters SIMPLE_P and VAR. If
5023 some statements are produced, emits them before BSI. */
5026 force_gimple_operand_bsi (block_stmt_iterator
*bsi
, tree expr
,
5027 bool simple_p
, tree var
)
5031 expr
= force_gimple_operand (expr
, &stmts
, simple_p
, var
);
5033 bsi_insert_before (bsi
, stmts
, BSI_SAME_STMT
);
5038 #include "gt-gimplify.h"