1 /* Control and data flow functions for trees.
2 Copyright 2001 Free Software Foundation, Inc.
3 Contributed by Alexandre Oliva <aoliva@redhat.com>
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
26 #include "tree-inline.h"
32 #include "insn-config.h"
33 #include "integrate.h"
36 #include "splay-tree.h"
37 #include "langhooks.h"
39 /* This should be eventually be generalized to other languages, but
40 this would require a shared function-as-trees infrastructure. */
43 /* 0 if we should not perform inlining.
44 1 if we should expand functions calls inline at the tree level.
45 2 if we should consider *all* functions to be inline
48 int flag_inline_trees
= 0;
52 o In order to make inlining-on-trees work, we pessimized
53 function-local static constants. In particular, they are now
54 always output, even when not addressed. Fix this by treating
55 function-local static constants just like global static
56 constants; the back-end already knows not to output them if they
59 o Provide heuristics to clamp inlining of recursive template
62 /* Data required for function inlining. */
64 typedef struct inline_data
66 /* A stack of the functions we are inlining. For example, if we are
67 compiling `f', which calls `g', which calls `h', and we are
68 inlining the body of `h', the stack will contain, `h', followed
69 by `g', followed by `f'. The first few elements of the stack may
70 contain other functions that we know we should not recurse into,
71 even though they are not directly being inlined. */
73 /* The index of the first element of FNS that really represents an
75 unsigned first_inlined_fn
;
76 /* The label to jump to when a return statement is encountered. If
77 this value is NULL, then return statements will simply be
78 remapped as return statements, rather than as jumps. */
80 /* The map from local declarations in the inlined function to
81 equivalents in the function into which it is being inlined. */
83 /* Nonzero if we are currently within the cleanup for a
85 int in_target_cleanup_p
;
86 /* A stack of the TARGET_EXPRs that we are currently processing. */
87 varray_type target_exprs
;
88 /* A list of the functions current function has inlined. */
89 varray_type inlined_fns
;
90 /* The approximate number of statements we have inlined in the
91 current call stack. */
93 /* We use the same mechanism to build clones that we do to perform
94 inlining. However, there are a few places where we need to
95 distinguish between those two situations. This flag is true if
96 we are cloning, rather than inlining. */
98 /* Hash table used to prevent walk_tree from visiting the same node
99 umpteen million times. */
105 static tree initialize_inlined_parameters
PARAMS ((inline_data
*, tree
, tree
));
106 static tree declare_return_variable
PARAMS ((inline_data
*, tree
*));
107 static tree copy_body_r
PARAMS ((tree
*, int *, void *));
108 static tree copy_body
PARAMS ((inline_data
*));
109 static tree expand_call_inline
PARAMS ((tree
*, int *, void *));
110 static void expand_calls_inline
PARAMS ((tree
*, inline_data
*));
111 static int inlinable_function_p
PARAMS ((tree
, inline_data
*));
112 static tree remap_decl
PARAMS ((tree
, inline_data
*));
113 static void remap_block
PARAMS ((tree
, tree
, inline_data
*));
114 static void copy_scope_stmt
PARAMS ((tree
*, int *, inline_data
*));
116 /* The approximate number of instructions per statement. This number
117 need not be particularly accurate; it is used only to make
118 decisions about when a function is too big to inline. */
119 #define INSNS_PER_STMT (10)
121 /* Remap DECL during the copying of the BLOCK tree for the function. */
124 remap_decl (decl
, id
)
131 /* We only remap local variables in the current function. */
132 fn
= VARRAY_TOP_TREE (id
->fns
);
133 if (! (*lang_hooks
.tree_inlining
.auto_var_in_fn_p
) (decl
, fn
))
136 /* See if we have remapped this declaration. */
137 n
= splay_tree_lookup (id
->decl_map
, (splay_tree_key
) decl
);
138 /* If we didn't already have an equivalent for this declaration,
144 /* Make a copy of the variable or label. */
145 t
= copy_decl_for_inlining (decl
, fn
,
146 VARRAY_TREE (id
->fns
, 0));
148 /* The decl T could be a dynamic array or other variable size type,
149 in which case some fields need to be remapped because they may
150 contain SAVE_EXPRs. */
151 if (TREE_TYPE (t
) && TREE_CODE (TREE_TYPE (t
)) == ARRAY_TYPE
152 && TYPE_DOMAIN (TREE_TYPE (t
)))
154 TREE_TYPE (t
) = copy_node (TREE_TYPE (t
));
155 TYPE_DOMAIN (TREE_TYPE (t
))
156 = copy_node (TYPE_DOMAIN (TREE_TYPE (t
)));
157 walk_tree (&TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (t
))),
158 copy_body_r
, id
, NULL
);
161 if (! DECL_NAME (t
) && TREE_TYPE (t
)
162 && (*lang_hooks
.tree_inlining
.anon_aggr_type_p
) (TREE_TYPE (t
)))
164 /* For a VAR_DECL of anonymous type, we must also copy the
165 member VAR_DECLS here and rechain the
166 DECL_ANON_UNION_ELEMS. */
170 for (src
= DECL_ANON_UNION_ELEMS (t
); src
;
171 src
= TREE_CHAIN (src
))
173 tree member
= remap_decl (TREE_VALUE (src
), id
);
175 if (TREE_PURPOSE (src
))
177 members
= tree_cons (NULL
, member
, members
);
179 DECL_ANON_UNION_ELEMS (t
) = nreverse (members
);
182 /* Remember it, so that if we encounter this local entity
183 again we can reuse this copy. */
184 n
= splay_tree_insert (id
->decl_map
,
185 (splay_tree_key
) decl
,
186 (splay_tree_value
) t
);
189 return (tree
) n
->value
;
192 /* Copy the SCOPE_STMT_BLOCK associated with SCOPE_STMT to contain
193 remapped versions of the variables therein. And hook the new block
194 into the block-tree. If non-NULL, the DECLS are declarations to
195 add to use instead of the BLOCK_VARS in the old block. */
198 remap_block (scope_stmt
, decls
, id
)
203 /* We cannot do this in the cleanup for a TARGET_EXPR since we do
204 not know whether or not expand_expr will actually write out the
205 code we put there. If it does not, then we'll have more BLOCKs
206 than block-notes, and things will go awry. At some point, we
207 should make the back-end handle BLOCK notes in a tidier way,
208 without requiring a strict correspondence to the block-tree; then
209 this check can go. */
210 if (id
->in_target_cleanup_p
)
212 SCOPE_STMT_BLOCK (scope_stmt
) = NULL_TREE
;
216 /* If this is the beginning of a scope, remap the associated BLOCK. */
217 if (SCOPE_BEGIN_P (scope_stmt
) && SCOPE_STMT_BLOCK (scope_stmt
))
224 /* Make the new block. */
225 old_block
= SCOPE_STMT_BLOCK (scope_stmt
);
226 new_block
= make_node (BLOCK
);
227 TREE_USED (new_block
) = TREE_USED (old_block
);
228 BLOCK_ABSTRACT_ORIGIN (new_block
) = old_block
;
229 SCOPE_STMT_BLOCK (scope_stmt
) = new_block
;
231 /* Remap its variables. */
232 for (old_var
= decls
? decls
: BLOCK_VARS (old_block
);
234 old_var
= TREE_CHAIN (old_var
))
238 /* Remap the variable. */
239 new_var
= remap_decl (old_var
, id
);
240 /* If we didn't remap this variable, so we can't mess with
241 its TREE_CHAIN. If we remapped this variable to
242 something other than a declaration (say, if we mapped it
243 to a constant), then we must similarly omit any mention
245 if (!new_var
|| !DECL_P (new_var
))
249 TREE_CHAIN (new_var
) = BLOCK_VARS (new_block
);
250 BLOCK_VARS (new_block
) = new_var
;
253 /* We put the BLOCK_VARS in reverse order; fix that now. */
254 BLOCK_VARS (new_block
) = nreverse (BLOCK_VARS (new_block
));
255 fn
= VARRAY_TREE (id
->fns
, 0);
257 /* We're building a clone; DECL_INITIAL is still
258 error_mark_node, and current_binding_level is the parm
260 insert_block (new_block
);
263 /* Attach this new block after the DECL_INITIAL block for the
264 function into which this block is being inlined. In
265 rest_of_compilation we will straighten out the BLOCK tree. */
267 if (DECL_INITIAL (fn
))
268 first_block
= &BLOCK_CHAIN (DECL_INITIAL (fn
));
270 first_block
= &DECL_INITIAL (fn
);
271 BLOCK_CHAIN (new_block
) = *first_block
;
272 *first_block
= new_block
;
274 /* Remember the remapped block. */
275 splay_tree_insert (id
->decl_map
,
276 (splay_tree_key
) old_block
,
277 (splay_tree_value
) new_block
);
279 /* If this is the end of a scope, set the SCOPE_STMT_BLOCK to be the
281 else if (SCOPE_END_P (scope_stmt
) && SCOPE_STMT_BLOCK (scope_stmt
))
285 /* Find this block in the table of remapped things. */
286 n
= splay_tree_lookup (id
->decl_map
,
287 (splay_tree_key
) SCOPE_STMT_BLOCK (scope_stmt
));
290 SCOPE_STMT_BLOCK (scope_stmt
) = (tree
) n
->value
;
294 /* Copy the SCOPE_STMT pointed to by TP. */
297 copy_scope_stmt (tp
, walk_subtrees
, id
)
304 /* Remember whether or not this statement was nullified. When
305 making a copy, copy_tree_r always sets SCOPE_NULLIFIED_P (and
306 doesn't copy the SCOPE_STMT_BLOCK) to free callers from having to
307 deal with copying BLOCKs if they do not wish to do so. */
308 block
= SCOPE_STMT_BLOCK (*tp
);
309 /* Copy (and replace) the statement. */
310 copy_tree_r (tp
, walk_subtrees
, NULL
);
311 /* Restore the SCOPE_STMT_BLOCK. */
312 SCOPE_STMT_BLOCK (*tp
) = block
;
314 /* Remap the associated block. */
315 remap_block (*tp
, NULL_TREE
, id
);
318 /* Called from copy_body via walk_tree. DATA is really an
322 copy_body_r (tp
, walk_subtrees
, data
)
331 id
= (inline_data
*) data
;
332 fn
= VARRAY_TOP_TREE (id
->fns
);
335 /* All automatic variables should have a DECL_CONTEXT indicating
336 what function they come from. */
337 if ((TREE_CODE (*tp
) == VAR_DECL
|| TREE_CODE (*tp
) == LABEL_DECL
)
338 && DECL_NAMESPACE_SCOPE_P (*tp
))
339 if (! DECL_EXTERNAL (*tp
) && ! TREE_STATIC (*tp
))
343 /* If this is a RETURN_STMT, change it into an EXPR_STMT and a
344 GOTO_STMT with the RET_LABEL as its target. */
345 if (TREE_CODE (*tp
) == RETURN_STMT
&& id
->ret_label
)
347 tree return_stmt
= *tp
;
350 /* Build the GOTO_STMT. */
351 goto_stmt
= build_stmt (GOTO_STMT
, id
->ret_label
);
352 TREE_CHAIN (goto_stmt
) = TREE_CHAIN (return_stmt
);
354 /* If we're returning something, just turn that into an
355 assignment into the equivalent of the original
357 if (RETURN_EXPR (return_stmt
))
359 *tp
= build_stmt (EXPR_STMT
,
360 RETURN_EXPR (return_stmt
));
361 STMT_IS_FULL_EXPR_P (*tp
) = 1;
362 /* And then jump to the end of the function. */
363 TREE_CHAIN (*tp
) = goto_stmt
;
365 /* If we're not returning anything just do the jump. */
369 /* Local variables and labels need to be replaced by equivalent
370 variables. We don't want to copy static variables; there's only
371 one of those, no matter how many times we inline the containing
373 else if ((*lang_hooks
.tree_inlining
.auto_var_in_fn_p
) (*tp
, fn
))
377 /* Remap the declaration. */
378 new_decl
= remap_decl (*tp
, id
);
381 /* Replace this variable with the copy. */
382 STRIP_TYPE_NOPS (new_decl
);
386 else if (nonstatic_local_decl_p (*tp
)
387 && DECL_CONTEXT (*tp
) != VARRAY_TREE (id
->fns
, 0))
390 else if (TREE_CODE (*tp
) == SAVE_EXPR
)
391 remap_save_expr (tp
, id
->decl_map
, VARRAY_TREE (id
->fns
, 0),
393 else if (TREE_CODE (*tp
) == UNSAVE_EXPR
)
394 /* UNSAVE_EXPRs should not be generated until expansion time. */
396 /* For a SCOPE_STMT, we must copy the associated block so that we
397 can write out debugging information for the inlined variables. */
398 else if (TREE_CODE (*tp
) == SCOPE_STMT
&& !id
->in_target_cleanup_p
)
399 copy_scope_stmt (tp
, walk_subtrees
, id
);
400 /* Otherwise, just copy the node. Note that copy_tree_r already
401 knows not to copy VAR_DECLs, etc., so this is safe. */
404 copy_tree_r (tp
, walk_subtrees
, NULL
);
406 /* The copied TARGET_EXPR has never been expanded, even if the
407 original node was expanded already. */
408 if (TREE_CODE (*tp
) == TARGET_EXPR
&& TREE_OPERAND (*tp
, 3))
410 TREE_OPERAND (*tp
, 1) = TREE_OPERAND (*tp
, 3);
411 TREE_OPERAND (*tp
, 3) = NULL_TREE
;
413 else if (TREE_CODE (*tp
) == MODIFY_EXPR
414 && TREE_OPERAND (*tp
, 0) == TREE_OPERAND (*tp
, 1)
415 && ((*lang_hooks
.tree_inlining
.auto_var_in_fn_p
)
416 (TREE_OPERAND (*tp
, 0), fn
)))
418 /* Some assignments VAR = VAR; don't generate any rtl code
419 and thus don't count as variable modification. Avoid
420 keeping bogosities like 0 = 0. */
421 tree decl
= TREE_OPERAND (*tp
, 0), value
;
424 n
= splay_tree_lookup (id
->decl_map
, (splay_tree_key
) decl
);
427 value
= (tree
) n
->value
;
428 STRIP_TYPE_NOPS (value
);
429 if (TREE_CONSTANT (value
) || TREE_READONLY_DECL_P (value
))
435 /* Keep iterating. */
439 /* Make a copy of the body of FN so that it can be inserted inline in
448 body
= DECL_SAVED_TREE (VARRAY_TOP_TREE (id
->fns
));
449 walk_tree (&body
, copy_body_r
, id
, NULL
);
454 /* Generate code to initialize the parameters of the function at the
455 top of the stack in ID from the ARGS (presented as a TREE_LIST). */
458 initialize_inlined_parameters (id
, args
, fn
)
468 /* Figure out what the parameters are. */
469 parms
= DECL_ARGUMENTS (fn
);
471 /* Start with no initializations whatsoever. */
472 init_stmts
= NULL_TREE
;
474 /* Loop through the parameter declarations, replacing each with an
475 equivalent VAR_DECL, appropriately initialized. */
476 for (p
= parms
, a
= args
; p
;
477 a
= a
? TREE_CHAIN (a
) : a
, p
= TREE_CHAIN (p
))
483 /* Find the initializer. */
484 value
= a
? TREE_VALUE (a
) : NULL_TREE
;
486 /* If the parameter is never assigned to, we may not need to
487 create a new variable here at all. Instead, we may be able
488 to just use the argument value. */
489 if (TREE_READONLY (p
)
490 && !TREE_ADDRESSABLE (p
)
491 && value
&& !TREE_SIDE_EFFECTS (value
))
493 /* Simplify the value, if possible. */
494 value
= fold (DECL_P (value
) ? decl_constant_value (value
) : value
);
496 /* We can't risk substituting complex expressions. They
497 might contain variables that will be assigned to later.
498 Theoretically, we could check the expression to see if
499 all of the variables that determine its value are
500 read-only, but we don't bother. */
501 if (TREE_CONSTANT (value
) || TREE_READONLY_DECL_P (value
))
503 /* If this is a declaration, wrap it a NOP_EXPR so that
504 we don't try to put the VALUE on the list of
507 value
= build1 (NOP_EXPR
, TREE_TYPE (value
), value
);
509 splay_tree_insert (id
->decl_map
,
511 (splay_tree_value
) value
);
516 /* Make an equivalent VAR_DECL. */
517 var
= copy_decl_for_inlining (p
, fn
, VARRAY_TREE (id
->fns
, 0));
518 /* Register the VAR_DECL as the equivalent for the PARM_DECL;
519 that way, when the PARM_DECL is encountered, it will be
520 automatically replaced by the VAR_DECL. */
521 splay_tree_insert (id
->decl_map
,
523 (splay_tree_value
) var
);
525 /* Declare this new variable. */
526 init_stmt
= build_stmt (DECL_STMT
, var
);
527 TREE_CHAIN (init_stmt
) = init_stmts
;
528 init_stmts
= init_stmt
;
530 /* Initialize this VAR_DECL from the equivalent argument. If
531 the argument is an object, created via a constructor or copy,
532 this will not result in an extra copy: the TARGET_EXPR
533 representing the argument will be bound to VAR, and the
534 object will be constructed in VAR. */
535 if (! TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (p
)))
536 DECL_INITIAL (var
) = value
;
539 /* Even if P was TREE_READONLY, the new VAR should not be.
540 In the original code, we would have constructed a
541 temporary, and then the function body would have never
542 changed the value of P. However, now, we will be
543 constructing VAR directly. The constructor body may
544 change its value multiple times as it is being
545 constructed. Therefore, it must not be TREE_READONLY;
546 the back-end assumes that TREE_READONLY variable is
547 assigned to only once. */
548 TREE_READONLY (var
) = 0;
550 /* Build a run-time initialization. */
551 init_stmt
= build_stmt (EXPR_STMT
,
552 build (INIT_EXPR
, TREE_TYPE (p
),
554 /* Add this initialization to the list. Note that we want the
555 declaration *after* the initialization because we are going
556 to reverse all the initialization statements below. */
557 TREE_CHAIN (init_stmt
) = init_stmts
;
558 init_stmts
= init_stmt
;
562 /* Evaluate trailing arguments. */
563 for (; a
; a
= TREE_CHAIN (a
))
568 /* Find the initializer. */
569 value
= a
? TREE_VALUE (a
) : NULL_TREE
;
571 if (! value
|| ! TREE_SIDE_EFFECTS (value
))
574 init_stmt
= build_stmt (EXPR_STMT
, value
);
575 TREE_CHAIN (init_stmt
) = init_stmts
;
576 init_stmts
= init_stmt
;
579 /* The initialization statements have been built up in reverse
580 order. Straighten them out now. */
581 return nreverse (init_stmts
);
584 /* Declare a return variable to replace the RESULT_DECL for the
585 function we are calling. An appropriate DECL_STMT is returned.
586 The USE_STMT is filled in to contain a use of the declaration to
587 indicate the return value of the function. */
590 declare_return_variable (id
, use_stmt
)
591 struct inline_data
*id
;
594 tree fn
= VARRAY_TOP_TREE (id
->fns
);
595 tree result
= DECL_RESULT (fn
);
597 int need_return_decl
= 1;
599 /* We don't need to do anything for functions that don't return
601 if (!result
|| VOID_TYPE_P (TREE_TYPE (result
)))
603 *use_stmt
= NULL_TREE
;
607 var
= ((*lang_hooks
.tree_inlining
.copy_res_decl_for_inlining
)
608 (result
, fn
, VARRAY_TREE (id
->fns
, 0), id
->decl_map
,
609 &need_return_decl
, &id
->target_exprs
));
611 /* Register the VAR_DECL as the equivalent for the RESULT_DECL; that
612 way, when the RESULT_DECL is encountered, it will be
613 automatically replaced by the VAR_DECL. */
614 splay_tree_insert (id
->decl_map
,
615 (splay_tree_key
) result
,
616 (splay_tree_value
) var
);
618 /* Build the USE_STMT. If the return type of the function was
619 promoted, convert it back to the expected type. */
620 if (TREE_TYPE (var
) == TREE_TYPE (TREE_TYPE (fn
)))
621 *use_stmt
= build_stmt (EXPR_STMT
, var
);
623 *use_stmt
= build_stmt (EXPR_STMT
,
624 build1 (NOP_EXPR
, TREE_TYPE (TREE_TYPE (fn
)),
627 /* Build the declaration statement if FN does not return an
629 if (need_return_decl
)
630 return build_stmt (DECL_STMT
, var
);
631 /* If FN does return an aggregate, there's no need to declare the
632 return variable; we're using a variable in our caller's frame. */
637 /* Returns non-zero if a function can be inlined as a tree. */
640 tree_inlinable_function_p (fn
)
643 return inlinable_function_p (fn
, NULL
);
646 /* Returns non-zero if FN is a function that can be inlined into the
647 inlining context ID_. If ID_ is NULL, check whether the function
648 can be inlined at all. */
651 inlinable_function_p (fn
, id
)
657 /* If we've already decided this function shouldn't be inlined,
658 there's no need to check again. */
659 if (DECL_UNINLINABLE (fn
))
662 /* Assume it is not inlinable. */
665 /* If we're not inlining things, then nothing is inlinable. */
666 if (! flag_inline_trees
)
668 /* If we're not inlining all functions and the function was not
669 declared `inline', we don't inline it. Don't think of
670 disregarding DECL_INLINE when flag_inline_trees == 2; it's the
671 front-end that must set DECL_INLINE in this case, because
672 dwarf2out loses if a function is inlined that doesn't have
674 else if (! DECL_INLINE (fn
))
676 /* We can't inline functions that are too big. Only allow a single
677 function to eat up half of our budget. Make special allowance
678 for extern inline functions, though. */
679 else if (! (*lang_hooks
.tree_inlining
.disregard_inline_limits
) (fn
)
680 && DECL_NUM_STMTS (fn
) * INSNS_PER_STMT
> MAX_INLINE_INSNS
/ 2)
682 /* All is well. We can inline this function. Traditionally, GCC
683 has refused to inline functions using alloca, or functions whose
684 values are returned in a PARALLEL, and a few other such obscure
685 conditions. We are not equally constrained at the tree level. */
689 /* Squirrel away the result so that we don't have to check again. */
690 DECL_UNINLINABLE (fn
) = ! inlinable
;
692 /* Even if this function is not itself too big to inline, it might
693 be that we've done so much inlining already that we don't want to
694 risk too much inlining any more and thus halve the acceptable
696 if (! (*lang_hooks
.tree_inlining
.disregard_inline_limits
) (fn
)
697 && ((DECL_NUM_STMTS (fn
) + (id
? id
->inlined_stmts
: 0)) * INSNS_PER_STMT
699 && DECL_NUM_STMTS (fn
) * INSNS_PER_STMT
> MAX_INLINE_INSNS
/ 4)
702 if (inlinable
&& (*lang_hooks
.tree_inlining
.cannot_inline_tree_fn
) (&fn
))
705 /* If we don't have the function body available, we can't inline
707 if (! DECL_SAVED_TREE (fn
))
710 /* Check again, language hooks may have modified it. */
711 if (! inlinable
|| DECL_UNINLINABLE (fn
))
714 /* Don't do recursive inlining, either. We don't record this in
715 DECL_UNINLINABLE; we may be able to inline this function later. */
720 for (i
= 0; i
< VARRAY_ACTIVE_SIZE (id
->fns
); ++i
)
721 if (VARRAY_TREE (id
->fns
, i
) == fn
)
724 if (DECL_INLINED_FNS (fn
))
727 tree inlined_fns
= DECL_INLINED_FNS (fn
);
729 for (j
= 0; j
< TREE_VEC_LENGTH (inlined_fns
); ++j
)
730 if (TREE_VEC_ELT (inlined_fns
, j
) == VARRAY_TREE (id
->fns
, 0))
735 /* Return the result. */
739 /* If *TP is a CALL_EXPR, replace it with its inline expansion. */
742 expand_call_inline (tp
, walk_subtrees
, data
)
758 /* See what we've got. */
759 id
= (inline_data
*) data
;
762 /* Recurse, but letting recursive invocations know that we are
763 inside the body of a TARGET_EXPR. */
764 if (TREE_CODE (*tp
) == TARGET_EXPR
)
766 int i
, len
= first_rtl_op (TARGET_EXPR
);
768 /* We're walking our own subtrees. */
771 /* Push *TP on the stack of pending TARGET_EXPRs. */
772 VARRAY_PUSH_TREE (id
->target_exprs
, *tp
);
774 /* Actually walk over them. This loop is the body of
775 walk_trees, omitting the case where the TARGET_EXPR
776 itself is handled. */
777 for (i
= 0; i
< len
; ++i
)
780 ++id
->in_target_cleanup_p
;
781 walk_tree (&TREE_OPERAND (*tp
, i
), expand_call_inline
, data
,
784 --id
->in_target_cleanup_p
;
787 /* We're done with this TARGET_EXPR now. */
788 VARRAY_POP (id
->target_exprs
);
794 /* Because types were not copied in copy_body, CALL_EXPRs beneath
795 them should not be expanded. This can happen if the type is a
796 dynamic array type, for example. */
799 /* From here on, we're only interested in CALL_EXPRs. */
800 if (TREE_CODE (t
) != CALL_EXPR
)
803 /* First, see if we can figure out what function is being called.
804 If we cannot, then there is no hope of inlining the function. */
805 fn
= get_callee_fndecl (t
);
809 /* Don't try to inline functions that are not well-suited to
811 if (!inlinable_function_p (fn
, id
))
814 /* Set the current filename and line number to the function we are
815 inlining so that when we create new _STMT nodes here they get
816 line numbers corresponding to the function we are calling. We
817 wrap the whole inlined body in an EXPR_WITH_FILE_AND_LINE as well
818 because individual statements don't record the filename. */
819 push_srcloc (fn
->decl
.filename
, fn
->decl
.linenum
);
821 /* Build a statement-expression containing code to initialize the
822 arguments, the actual inline expansion of the body, and a label
823 for the return statements within the function to jump to. The
824 type of the statement expression is the return type of the
826 expr
= build1 (STMT_EXPR
, TREE_TYPE (TREE_TYPE (fn
)), NULL_TREE
);
828 /* Local declarations will be replaced by their equivalents in this
831 id
->decl_map
= splay_tree_new (splay_tree_compare_pointers
,
834 /* Initialize the parameters. */
835 arg_inits
= initialize_inlined_parameters (id
, TREE_OPERAND (t
, 1), fn
);
836 /* Expand any inlined calls in the initializers. Do this before we
837 push FN on the stack of functions we are inlining; we want to
838 inline calls to FN that appear in the initializers for the
840 expand_calls_inline (&arg_inits
, id
);
841 /* And add them to the tree. */
842 STMT_EXPR_STMT (expr
) = chainon (STMT_EXPR_STMT (expr
), arg_inits
);
844 /* Record the function we are about to inline so that we can avoid
845 recursing into it. */
846 VARRAY_PUSH_TREE (id
->fns
, fn
);
848 /* Record the function we are about to inline if optimize_function
849 has not been called on it yet and we don't have it in the list. */
850 if (! DECL_INLINED_FNS (fn
))
854 for (i
= VARRAY_ACTIVE_SIZE (id
->inlined_fns
) - 1; i
>= 0; i
--)
855 if (VARRAY_TREE (id
->inlined_fns
, i
) == fn
)
858 VARRAY_PUSH_TREE (id
->inlined_fns
, fn
);
861 /* Return statements in the function body will be replaced by jumps
863 id
->ret_label
= build_decl (LABEL_DECL
, NULL_TREE
, NULL_TREE
);
864 DECL_CONTEXT (id
->ret_label
) = VARRAY_TREE (id
->fns
, 0);
866 /* Create a block to put the parameters in. We have to do this
867 after the parameters have been remapped because remapping
868 parameters is different from remapping ordinary variables. */
869 scope_stmt
= build_stmt (SCOPE_STMT
, DECL_INITIAL (fn
));
870 SCOPE_BEGIN_P (scope_stmt
) = 1;
871 SCOPE_NO_CLEANUPS_P (scope_stmt
) = 1;
872 remap_block (scope_stmt
, DECL_ARGUMENTS (fn
), id
);
873 TREE_CHAIN (scope_stmt
) = STMT_EXPR_STMT (expr
);
874 STMT_EXPR_STMT (expr
) = scope_stmt
;
876 /* Tell the debugging backends that this block represents the
877 outermost scope of the inlined function. */
878 if (SCOPE_STMT_BLOCK (scope_stmt
))
879 BLOCK_ABSTRACT_ORIGIN (SCOPE_STMT_BLOCK (scope_stmt
)) = DECL_ORIGIN (fn
);
881 /* Declare the return variable for the function. */
882 STMT_EXPR_STMT (expr
)
883 = chainon (STMT_EXPR_STMT (expr
),
884 declare_return_variable (id
, &use_stmt
));
886 /* After we've initialized the parameters, we insert the body of the
888 inlined_body
= &STMT_EXPR_STMT (expr
);
889 while (*inlined_body
)
890 inlined_body
= &TREE_CHAIN (*inlined_body
);
891 *inlined_body
= copy_body (id
);
893 /* Close the block for the parameters. */
894 scope_stmt
= build_stmt (SCOPE_STMT
, DECL_INITIAL (fn
));
895 SCOPE_NO_CLEANUPS_P (scope_stmt
) = 1;
896 if (! DECL_INITIAL (fn
)
897 || TREE_CODE (DECL_INITIAL (fn
)) != BLOCK
)
899 remap_block (scope_stmt
, NULL_TREE
, id
);
900 STMT_EXPR_STMT (expr
)
901 = chainon (STMT_EXPR_STMT (expr
), scope_stmt
);
903 /* After the body of the function comes the RET_LABEL. This must come
904 before we evaluate the returned value below, because that evalulation
905 may cause RTL to be generated. */
906 STMT_EXPR_STMT (expr
)
907 = chainon (STMT_EXPR_STMT (expr
),
908 build_stmt (LABEL_STMT
, id
->ret_label
));
910 /* Finally, mention the returned value so that the value of the
911 statement-expression is the returned value of the function. */
912 STMT_EXPR_STMT (expr
) = chainon (STMT_EXPR_STMT (expr
), use_stmt
);
915 splay_tree_delete (id
->decl_map
);
918 /* The new expression has side-effects if the old one did. */
919 TREE_SIDE_EFFECTS (expr
) = TREE_SIDE_EFFECTS (t
);
921 /* Replace the call by the inlined body. Wrap it in an
922 EXPR_WITH_FILE_LOCATION so that we'll get debugging line notes
923 pointing to the right place. */
924 chain
= TREE_CHAIN (*tp
);
925 *tp
= build_expr_wfl (expr
, DECL_SOURCE_FILE (fn
), DECL_SOURCE_LINE (fn
),
927 EXPR_WFL_EMIT_LINE_NOTE (*tp
) = 1;
928 TREE_CHAIN (*tp
) = chain
;
931 /* If the value of the new expression is ignored, that's OK. We
932 don't warn about this for CALL_EXPRs, so we shouldn't warn about
933 the equivalent inlined version either. */
936 /* Our function now has more statements than it did before. */
937 DECL_NUM_STMTS (VARRAY_TREE (id
->fns
, 0)) += DECL_NUM_STMTS (fn
);
938 id
->inlined_stmts
+= DECL_NUM_STMTS (fn
);
940 /* Recurse into the body of the just inlined function. */
941 expand_calls_inline (inlined_body
, id
);
942 VARRAY_POP (id
->fns
);
944 /* If we've returned to the top level, clear out the record of how
945 much inlining has been done. */
946 if (VARRAY_ACTIVE_SIZE (id
->fns
) == id
->first_inlined_fn
)
947 id
->inlined_stmts
= 0;
949 /* Don't walk into subtrees. We've already handled them above. */
952 /* Keep iterating. */
956 /* Walk over the entire tree *TP, replacing CALL_EXPRs with inline
957 expansions as appropriate. */
960 expand_calls_inline (tp
, id
)
964 /* Search through *TP, replacing all calls to inline functions by
965 appropriate equivalents. Use walk_tree in no-duplicates mode
966 to avoid exponential time complexity. (We can't just use
967 walk_tree_without_duplicates, because of the special TARGET_EXPR
968 handling in expand_calls. The hash table is set up in
969 optimize_function. */
970 walk_tree (tp
, expand_call_inline
, id
, id
->tree_pruner
);
973 /* Expand calls to inline functions in the body of FN. */
976 optimize_inline_calls (fn
)
983 memset (&id
, 0, sizeof (id
));
985 /* Don't allow recursion into FN. */
986 VARRAY_TREE_INIT (id
.fns
, 32, "fns");
987 VARRAY_PUSH_TREE (id
.fns
, fn
);
988 /* Or any functions that aren't finished yet. */
990 if (current_function_decl
)
992 VARRAY_PUSH_TREE (id
.fns
, current_function_decl
);
993 prev_fn
= current_function_decl
;
996 prev_fn
= ((*lang_hooks
.tree_inlining
.add_pending_fn_decls
)
999 /* Create the stack of TARGET_EXPRs. */
1000 VARRAY_TREE_INIT (id
.target_exprs
, 32, "target_exprs");
1002 /* Create the list of functions this call will inline. */
1003 VARRAY_TREE_INIT (id
.inlined_fns
, 32, "inlined_fns");
1005 /* Keep track of the low-water mark, i.e., the point where the first
1006 real inlining is represented in ID.FNS. */
1007 id
.first_inlined_fn
= VARRAY_ACTIVE_SIZE (id
.fns
);
1009 /* Replace all calls to inline functions with the bodies of those
1011 id
.tree_pruner
= htab_create (37, htab_hash_pointer
,
1012 htab_eq_pointer
, NULL
);
1013 expand_calls_inline (&DECL_SAVED_TREE (fn
), &id
);
1016 htab_delete (id
.tree_pruner
);
1017 VARRAY_FREE (id
.fns
);
1018 VARRAY_FREE (id
.target_exprs
);
1019 if (DECL_LANG_SPECIFIC (fn
))
1021 tree ifn
= make_tree_vec (VARRAY_ACTIVE_SIZE (id
.inlined_fns
));
1023 memcpy (&TREE_VEC_ELT (ifn
, 0), &VARRAY_TREE (id
.inlined_fns
, 0),
1024 VARRAY_ACTIVE_SIZE (id
.inlined_fns
) * sizeof (tree
));
1025 DECL_INLINED_FNS (fn
) = ifn
;
1027 VARRAY_FREE (id
.inlined_fns
);
1030 /* FN is a function that has a complete body, and CLONE is a function
1031 whose body is to be set to a copy of FN, mapping argument
1032 declarations according to the ARG_MAP splay_tree. */
1035 clone_body (clone
, fn
, arg_map
)
1041 /* Clone the body, as if we were making an inline call. But, remap
1042 the parameters in the callee to the parameters of caller. If
1043 there's an in-charge parameter, map it to an appropriate
1045 memset (&id
, 0, sizeof (id
));
1046 VARRAY_TREE_INIT (id
.fns
, 2, "fns");
1047 VARRAY_PUSH_TREE (id
.fns
, clone
);
1048 VARRAY_PUSH_TREE (id
.fns
, fn
);
1049 id
.decl_map
= (splay_tree
)arg_map
;
1051 /* Cloning is treated slightly differently from inlining. Set
1052 CLONING_P so that it's clear which operation we're performing. */
1053 id
.cloning_p
= true;
1055 /* Actually copy the body. */
1056 TREE_CHAIN (DECL_SAVED_TREE (clone
)) = copy_body (&id
);
1059 VARRAY_FREE (id
.fns
);
1062 /* Apply FUNC to all the sub-trees of TP in a pre-order traversal.
1063 FUNC is called with the DATA and the address of each sub-tree. If
1064 FUNC returns a non-NULL value, the traversal is aborted, and the
1065 value returned by FUNC is returned. If HTAB is non-NULL it is used
1066 to record the nodes visited, and to avoid visiting a node more than
1070 walk_tree (tp
, func
, data
, htab_
)
1076 htab_t htab
= (htab_t
) htab_
;
1077 enum tree_code code
;
1081 #define WALK_SUBTREE(NODE) \
1084 result = walk_tree (&(NODE), func, data, htab); \
1090 #define WALK_SUBTREE_TAIL(NODE) \
1094 goto tail_recurse; \
1099 /* Skip empty subtrees. */
1107 /* Don't walk the same tree twice, if the user has requested
1108 that we avoid doing so. */
1109 if (htab_find (htab
, *tp
))
1111 /* If we haven't already seen this node, add it to the table. */
1112 slot
= htab_find_slot (htab
, *tp
, INSERT
);
1116 /* Call the function. */
1118 result
= (*func
) (tp
, &walk_subtrees
, data
);
1120 /* If we found something, return it. */
1124 code
= TREE_CODE (*tp
);
1126 /* Even if we didn't, FUNC may have decided that there was nothing
1127 interesting below this point in the tree. */
1130 if (statement_code_p (code
) || code
== TREE_LIST
1131 || (*lang_hooks
.tree_inlining
.tree_chain_matters_p
) (*tp
))
1132 /* But we still need to check our siblings. */
1133 WALK_SUBTREE_TAIL (TREE_CHAIN (*tp
));
1138 /* Handle common cases up front. */
1139 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code
))
1140 || TREE_CODE_CLASS (code
) == 'r'
1141 || TREE_CODE_CLASS (code
) == 's')
1145 /* Set lineno here so we get the right instantiation context
1146 if we call instantiate_decl from inlinable_function_p. */
1147 if (statement_code_p (code
) && !STMT_LINENO_FOR_FN_P (*tp
))
1148 lineno
= STMT_LINENO (*tp
);
1150 /* Walk over all the sub-trees of this operand. */
1151 len
= first_rtl_op (code
);
1152 /* TARGET_EXPRs are peculiar: operands 1 and 3 can be the same.
1153 But, we only want to walk once. */
1154 if (code
== TARGET_EXPR
1155 && TREE_OPERAND (*tp
, 3) == TREE_OPERAND (*tp
, 1))
1157 /* Go through the subtrees. We need to do this in forward order so
1158 that the scope of a FOR_EXPR is handled properly. */
1159 for (i
= 0; i
< len
; ++i
)
1160 WALK_SUBTREE (TREE_OPERAND (*tp
, i
));
1162 /* For statements, we also walk the chain so that we cover the
1163 entire statement tree. */
1164 if (statement_code_p (code
))
1166 if (code
== DECL_STMT
1167 && DECL_STMT_DECL (*tp
)
1168 && DECL_P (DECL_STMT_DECL (*tp
)))
1170 /* Walk the DECL_INITIAL and DECL_SIZE. We don't want to walk
1171 into declarations that are just mentioned, rather than
1172 declared; they don't really belong to this part of the tree.
1173 And, we can see cycles: the initializer for a declaration can
1174 refer to the declaration itself. */
1175 WALK_SUBTREE (DECL_INITIAL (DECL_STMT_DECL (*tp
)));
1176 WALK_SUBTREE (DECL_SIZE (DECL_STMT_DECL (*tp
)));
1177 WALK_SUBTREE (DECL_SIZE_UNIT (DECL_STMT_DECL (*tp
)));
1180 /* This can be tail-recursion optimized if we write it this way. */
1181 WALK_SUBTREE_TAIL (TREE_CHAIN (*tp
));
1184 /* We didn't find what we were looking for. */
1187 else if (TREE_CODE_CLASS (code
) == 'd')
1189 WALK_SUBTREE_TAIL (TREE_TYPE (*tp
));
1192 result
= (*lang_hooks
.tree_inlining
.walk_subtrees
) (tp
, &walk_subtrees
, func
,
1194 if (result
|| ! walk_subtrees
)
1197 /* Not one of the easy cases. We must explicitly go through the
1202 case IDENTIFIER_NODE
:
1215 /* None of thse have subtrees other than those already walked
1220 case REFERENCE_TYPE
:
1221 WALK_SUBTREE_TAIL (TREE_TYPE (*tp
));
1225 WALK_SUBTREE (TREE_VALUE (*tp
));
1226 WALK_SUBTREE_TAIL (TREE_CHAIN (*tp
));
1231 int len
= TREE_VEC_LENGTH (*tp
);
1236 /* Walk all elements but the first. */
1238 WALK_SUBTREE (TREE_VEC_ELT (*tp
, len
));
1240 /* Now walk the first one as a tail call. */
1241 WALK_SUBTREE_TAIL (TREE_VEC_ELT (*tp
, 0));
1245 WALK_SUBTREE (TREE_REALPART (*tp
));
1246 WALK_SUBTREE_TAIL (TREE_IMAGPART (*tp
));
1249 WALK_SUBTREE_TAIL (CONSTRUCTOR_ELTS (*tp
));
1252 WALK_SUBTREE (TYPE_METHOD_BASETYPE (*tp
));
1256 WALK_SUBTREE (TREE_TYPE (*tp
));
1258 tree arg
= TYPE_ARG_TYPES (*tp
);
1260 /* We never want to walk into default arguments. */
1261 for (; arg
; arg
= TREE_CHAIN (arg
))
1262 WALK_SUBTREE (TREE_VALUE (arg
));
1267 WALK_SUBTREE (TREE_TYPE (*tp
));
1268 WALK_SUBTREE_TAIL (TYPE_DOMAIN (*tp
));
1271 WALK_SUBTREE (TYPE_MIN_VALUE (*tp
));
1272 WALK_SUBTREE_TAIL (TYPE_MAX_VALUE (*tp
));
1275 WALK_SUBTREE (TREE_TYPE (*tp
));
1276 WALK_SUBTREE_TAIL (TYPE_OFFSET_BASETYPE (*tp
));
1282 /* We didn't find what we were looking for. */
1288 /* Like walk_tree, but does not walk duplicate nodes more than
1292 walk_tree_without_duplicates (tp
, func
, data
)
1300 htab
= htab_create (37, htab_hash_pointer
, htab_eq_pointer
, NULL
);
1301 result
= walk_tree (tp
, func
, data
, htab
);
1306 /* Passed to walk_tree. Copies the node pointed to, if appropriate. */
1309 copy_tree_r (tp
, walk_subtrees
, data
)
1312 void *data ATTRIBUTE_UNUSED
;
1314 enum tree_code code
= TREE_CODE (*tp
);
1316 /* We make copies of most nodes. */
1317 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code
))
1318 || TREE_CODE_CLASS (code
) == 'r'
1319 || TREE_CODE_CLASS (code
) == 'c'
1320 || TREE_CODE_CLASS (code
) == 's'
1321 || code
== TREE_LIST
1323 || (*lang_hooks
.tree_inlining
.tree_chain_matters_p
) (*tp
))
1325 /* Because the chain gets clobbered when we make a copy, we save it
1327 tree chain
= TREE_CHAIN (*tp
);
1329 /* Copy the node. */
1330 *tp
= copy_node (*tp
);
1332 /* Now, restore the chain, if appropriate. That will cause
1333 walk_tree to walk into the chain as well. */
1334 if (code
== PARM_DECL
|| code
== TREE_LIST
1335 || (*lang_hooks
.tree_inlining
.tree_chain_matters_p
) (*tp
)
1336 || statement_code_p (code
))
1337 TREE_CHAIN (*tp
) = chain
;
1339 /* For now, we don't update BLOCKs when we make copies. So, we
1340 have to nullify all scope-statements. */
1341 if (TREE_CODE (*tp
) == SCOPE_STMT
)
1342 SCOPE_STMT_BLOCK (*tp
) = NULL_TREE
;
1344 else if (TREE_CODE_CLASS (code
) == 't')
1345 /* There's no need to copy types, or anything beneath them. */
1351 /* The SAVE_EXPR pointed to by TP is being copied. If ST contains
1352 information indicating to what new SAVE_EXPR this one should be
1353 mapped, use that one. Otherwise, create a new node and enter it in
1354 ST. FN is the function into which the copy will be placed. */
1357 remap_save_expr (tp
, st_
, fn
, walk_subtrees
)
1363 splay_tree st
= (splay_tree
) st_
;
1366 /* See if we already encountered this SAVE_EXPR. */
1367 n
= splay_tree_lookup (st
, (splay_tree_key
) *tp
);
1369 /* If we didn't already remap this SAVE_EXPR, do so now. */
1372 tree t
= copy_node (*tp
);
1374 /* The SAVE_EXPR is now part of the function into which we
1375 are inlining this body. */
1376 SAVE_EXPR_CONTEXT (t
) = fn
;
1377 /* And we haven't evaluated it yet. */
1378 SAVE_EXPR_RTL (t
) = NULL_RTX
;
1379 /* Remember this SAVE_EXPR. */
1380 n
= splay_tree_insert (st
,
1381 (splay_tree_key
) *tp
,
1382 (splay_tree_value
) t
);
1383 /* Make sure we don't remap an already-remapped SAVE_EXPR. */
1384 splay_tree_insert (st
, (splay_tree_key
) t
,
1385 (splay_tree_value
) error_mark_node
);
1388 /* We've already walked into this SAVE_EXPR, so we needn't do it
1392 /* Replace this SAVE_EXPR with the copy. */
1393 *tp
= (tree
) n
->value
;