1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000 Free Software Foundation, Inc.
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. */
22 /* This file handles the generation of rtl code from tree structure
23 above the level of expressions, using subroutines in exp*.c and emit-rtl.c.
24 It also creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 The functions whose names start with `expand_' are called by the
28 parser to generate RTL instructions for various kinds of constructs.
30 Some control and binding constructs require calling several such
31 functions at different times. For example, a simple if-then
32 is expanded by calling `expand_start_cond' (with the condition-expression
33 as argument) before parsing the then-clause and calling `expand_end_cond'
34 after parsing the then-clause. */
45 #include "insn-config.h"
47 #include "hard-reg-set.h"
56 #define obstack_chunk_alloc xmalloc
57 #define obstack_chunk_free free
58 struct obstack stmt_obstack
;
60 /* Assume that case vectors are not pc-relative. */
61 #ifndef CASE_VECTOR_PC_RELATIVE
62 #define CASE_VECTOR_PC_RELATIVE 0
65 /* Functions and data structures for expanding case statements. */
67 /* Case label structure, used to hold info on labels within case
68 statements. We handle "range" labels; for a single-value label
69 as in C, the high and low limits are the same.
71 An AVL tree of case nodes is initially created, and later transformed
72 to a list linked via the RIGHT fields in the nodes. Nodes with
73 higher case values are later in the list.
75 Switch statements can be output in one of two forms. A branch table
76 is used if there are more than a few labels and the labels are dense
77 within the range between the smallest and largest case value. If a
78 branch table is used, no further manipulations are done with the case
81 The alternative to the use of a branch table is to generate a series
82 of compare and jump insns. When that is done, we use the LEFT, RIGHT,
83 and PARENT fields to hold a binary tree. Initially the tree is
84 totally unbalanced, with everything on the right. We balance the tree
85 with nodes on the left having lower case values than the parent
86 and nodes on the right having higher values. We then output the tree
91 struct case_node
*left
; /* Left son in binary tree */
92 struct case_node
*right
; /* Right son in binary tree; also node chain */
93 struct case_node
*parent
; /* Parent of node in binary tree */
94 tree low
; /* Lowest index value for this label */
95 tree high
; /* Highest index value for this label */
96 tree code_label
; /* Label to jump to when node matches */
100 typedef struct case_node case_node
;
101 typedef struct case_node
*case_node_ptr
;
103 /* These are used by estimate_case_costs and balance_case_nodes. */
105 /* This must be a signed type, and non-ANSI compilers lack signed char. */
106 static short cost_table_
[129];
107 static int use_cost_table
;
108 static int cost_table_initialized
;
110 /* Special care is needed because we allow -1, but TREE_INT_CST_LOW
112 #define COST_TABLE(I) cost_table_[(unsigned HOST_WIDE_INT)((I) + 1)]
114 /* Stack of control and binding constructs we are currently inside.
116 These constructs begin when you call `expand_start_WHATEVER'
117 and end when you call `expand_end_WHATEVER'. This stack records
118 info about how the construct began that tells the end-function
119 what to do. It also may provide information about the construct
120 to alter the behavior of other constructs within the body.
121 For example, they may affect the behavior of C `break' and `continue'.
123 Each construct gets one `struct nesting' object.
124 All of these objects are chained through the `all' field.
125 `nesting_stack' points to the first object (innermost construct).
126 The position of an entry on `nesting_stack' is in its `depth' field.
128 Each type of construct has its own individual stack.
129 For example, loops have `loop_stack'. Each object points to the
130 next object of the same type through the `next' field.
132 Some constructs are visible to `break' exit-statements and others
133 are not. Which constructs are visible depends on the language.
134 Therefore, the data structure allows each construct to be visible
135 or not, according to the args given when the construct is started.
136 The construct is visible if the `exit_label' field is non-null.
137 In that case, the value should be a CODE_LABEL rtx. */
142 struct nesting
*next
;
147 /* For conds (if-then and if-then-else statements). */
150 /* Label for the end of the if construct.
151 There is none if EXITFLAG was not set
152 and no `else' has been seen yet. */
154 /* Label for the end of this alternative.
155 This may be the end of the if or the next else/elseif. */
161 /* Label at the top of the loop; place to loop back to. */
163 /* Label at the end of the whole construct. */
165 /* Label before a jump that branches to the end of the whole
166 construct. This is where destructors go if any. */
168 /* Label for `continue' statement to jump to;
169 this is in front of the stepper of the loop. */
172 /* For variable binding contours. */
175 /* Sequence number of this binding contour within the function,
176 in order of entry. */
177 int block_start_count
;
178 /* Nonzero => value to restore stack to on exit. */
180 /* The NOTE that starts this contour.
181 Used by expand_goto to check whether the destination
182 is within each contour or not. */
184 /* Innermost containing binding contour that has a stack level. */
185 struct nesting
*innermost_stack_block
;
186 /* List of cleanups to be run on exit from this contour.
187 This is a list of expressions to be evaluated.
188 The TREE_PURPOSE of each link is the ..._DECL node
189 which the cleanup pertains to. */
191 /* List of cleanup-lists of blocks containing this block,
192 as they were at the locus where this block appears.
193 There is an element for each containing block,
194 ordered innermost containing block first.
195 The tail of this list can be 0,
196 if all remaining elements would be empty lists.
197 The element's TREE_VALUE is the cleanup-list of that block,
198 which may be null. */
200 /* Chain of labels defined inside this binding contour.
201 For contours that have stack levels or cleanups. */
202 struct label_chain
*label_chain
;
203 /* Number of function calls seen, as of start of this block. */
204 int n_function_calls
;
205 /* Nonzero if this is associated with a EH region. */
206 int exception_region
;
207 /* The saved target_temp_slot_level from our outer block.
208 We may reset target_temp_slot_level to be the level of
209 this block, if that is done, target_temp_slot_level
210 reverts to the saved target_temp_slot_level at the very
212 int block_target_temp_slot_level
;
213 /* True if we are currently emitting insns in an area of
214 output code that is controlled by a conditional
215 expression. This is used by the cleanup handling code to
216 generate conditional cleanup actions. */
217 int conditional_code
;
218 /* A place to move the start of the exception region for any
219 of the conditional cleanups, must be at the end or after
220 the start of the last unconditional cleanup, and before any
221 conditional branch points. */
222 rtx last_unconditional_cleanup
;
223 /* When in a conditional context, this is the specific
224 cleanup list associated with last_unconditional_cleanup,
225 where we place the conditionalized cleanups. */
228 /* For switch (C) or case (Pascal) statements,
229 and also for dummies (see `expand_start_case_dummy'). */
232 /* The insn after which the case dispatch should finally
233 be emitted. Zero for a dummy. */
235 /* A list of case labels; it is first built as an AVL tree.
236 During expand_end_case, this is converted to a list, and may be
237 rearranged into a nearly balanced binary tree. */
238 struct case_node
*case_list
;
239 /* Label to jump to if no case matches. */
241 /* The expression to be dispatched on. */
243 /* Type that INDEX_EXPR should be converted to. */
245 /* Name of this kind of statement, for warnings. */
246 const char *printname
;
247 /* Used to save no_line_numbers till we see the first case label.
248 We set this to -1 when we see the first case label in this
250 int line_number_status
;
255 /* Allocate and return a new `struct nesting'. */
257 #define ALLOC_NESTING() \
258 (struct nesting *) obstack_alloc (&stmt_obstack, sizeof (struct nesting))
260 /* Pop the nesting stack element by element until we pop off
261 the element which is at the top of STACK.
262 Update all the other stacks, popping off elements from them
263 as we pop them from nesting_stack. */
265 #define POPSTACK(STACK) \
266 do { struct nesting *target = STACK; \
267 struct nesting *this; \
268 do { this = nesting_stack; \
269 if (loop_stack == this) \
270 loop_stack = loop_stack->next; \
271 if (cond_stack == this) \
272 cond_stack = cond_stack->next; \
273 if (block_stack == this) \
274 block_stack = block_stack->next; \
275 if (stack_block_stack == this) \
276 stack_block_stack = stack_block_stack->next; \
277 if (case_stack == this) \
278 case_stack = case_stack->next; \
279 nesting_depth = nesting_stack->depth - 1; \
280 nesting_stack = this->all; \
281 obstack_free (&stmt_obstack, this); } \
282 while (this != target); } while (0)
284 /* In some cases it is impossible to generate code for a forward goto
285 until the label definition is seen. This happens when it may be necessary
286 for the goto to reset the stack pointer: we don't yet know how to do that.
287 So expand_goto puts an entry on this fixup list.
288 Each time a binding contour that resets the stack is exited,
290 If the target label has now been defined, we can insert the proper code. */
294 /* Points to following fixup. */
295 struct goto_fixup
*next
;
296 /* Points to the insn before the jump insn.
297 If more code must be inserted, it goes after this insn. */
299 /* The LABEL_DECL that this jump is jumping to, or 0
300 for break, continue or return. */
302 /* The BLOCK for the place where this goto was found. */
304 /* The CODE_LABEL rtx that this is jumping to. */
306 /* Number of binding contours started in current function
307 before the label reference. */
308 int block_start_count
;
309 /* The outermost stack level that should be restored for this jump.
310 Each time a binding contour that resets the stack is exited,
311 if the target label is *not* yet defined, this slot is updated. */
313 /* List of lists of cleanup expressions to be run by this goto.
314 There is one element for each block that this goto is within.
315 The tail of this list can be 0,
316 if all remaining elements would be empty.
317 The TREE_VALUE contains the cleanup list of that block as of the
318 time this goto was seen.
319 The TREE_ADDRESSABLE flag is 1 for a block that has been exited. */
320 tree cleanup_list_list
;
323 /* Within any binding contour that must restore a stack level,
324 all labels are recorded with a chain of these structures. */
328 /* Points to following fixup. */
329 struct label_chain
*next
;
335 /* Chain of all pending binding contours. */
336 struct nesting
*x_block_stack
;
338 /* If any new stacks are added here, add them to POPSTACKS too. */
340 /* Chain of all pending binding contours that restore stack levels
342 struct nesting
*x_stack_block_stack
;
344 /* Chain of all pending conditional statements. */
345 struct nesting
*x_cond_stack
;
347 /* Chain of all pending loops. */
348 struct nesting
*x_loop_stack
;
350 /* Chain of all pending case or switch statements. */
351 struct nesting
*x_case_stack
;
353 /* Separate chain including all of the above,
354 chained through the `all' field. */
355 struct nesting
*x_nesting_stack
;
357 /* Number of entries on nesting_stack now. */
360 /* Number of binding contours started so far in this function. */
361 int x_block_start_count
;
363 /* Each time we expand an expression-statement,
364 record the expr's type and its RTL value here. */
365 tree x_last_expr_type
;
366 rtx x_last_expr_value
;
368 /* Nonzero if within a ({...}) grouping, in which case we must
369 always compute a value for each expr-stmt in case it is the last one. */
370 int x_expr_stmts_for_value
;
372 /* Filename and line number of last line-number note,
373 whether we actually emitted it or not. */
374 const char *x_emit_filename
;
377 struct goto_fixup
*x_goto_fixup_chain
;
380 #define block_stack (cfun->stmt->x_block_stack)
381 #define stack_block_stack (cfun->stmt->x_stack_block_stack)
382 #define cond_stack (cfun->stmt->x_cond_stack)
383 #define loop_stack (cfun->stmt->x_loop_stack)
384 #define case_stack (cfun->stmt->x_case_stack)
385 #define nesting_stack (cfun->stmt->x_nesting_stack)
386 #define nesting_depth (cfun->stmt->x_nesting_depth)
387 #define current_block_start_count (cfun->stmt->x_block_start_count)
388 #define last_expr_type (cfun->stmt->x_last_expr_type)
389 #define last_expr_value (cfun->stmt->x_last_expr_value)
390 #define expr_stmts_for_value (cfun->stmt->x_expr_stmts_for_value)
391 #define emit_filename (cfun->stmt->x_emit_filename)
392 #define emit_lineno (cfun->stmt->x_emit_lineno)
393 #define goto_fixup_chain (cfun->stmt->x_goto_fixup_chain)
395 /* Non-zero if we are using EH to handle cleanus. */
396 static int using_eh_for_cleanups_p
= 0;
398 static int n_occurrences
PARAMS ((int, const char *));
399 static void expand_goto_internal
PARAMS ((tree
, rtx
, rtx
));
400 static int expand_fixup
PARAMS ((tree
, rtx
, rtx
));
401 static rtx expand_nl_handler_label
PARAMS ((rtx
, rtx
));
402 static void expand_nl_goto_receiver
PARAMS ((void));
403 static void expand_nl_goto_receivers
PARAMS ((struct nesting
*));
404 static void fixup_gotos
PARAMS ((struct nesting
*, rtx
, tree
,
406 static void expand_null_return_1
PARAMS ((rtx
, int));
407 static void expand_value_return
PARAMS ((rtx
));
408 static int tail_recursion_args
PARAMS ((tree
, tree
));
409 static void expand_cleanups
PARAMS ((tree
, tree
, int, int));
410 static void check_seenlabel
PARAMS ((void));
411 static void do_jump_if_equal
PARAMS ((rtx
, rtx
, rtx
, int));
412 static int estimate_case_costs
PARAMS ((case_node_ptr
));
413 static void group_case_nodes
PARAMS ((case_node_ptr
));
414 static void balance_case_nodes
PARAMS ((case_node_ptr
*,
416 static int node_has_low_bound
PARAMS ((case_node_ptr
, tree
));
417 static int node_has_high_bound
PARAMS ((case_node_ptr
, tree
));
418 static int node_is_bounded
PARAMS ((case_node_ptr
, tree
));
419 static void emit_jump_if_reachable
PARAMS ((rtx
));
420 static void emit_case_nodes
PARAMS ((rtx
, case_node_ptr
, rtx
, tree
));
421 static struct case_node
*case_tree2list
PARAMS ((case_node
*, case_node
*));
422 static void mark_cond_nesting
PARAMS ((struct nesting
*));
423 static void mark_loop_nesting
PARAMS ((struct nesting
*));
424 static void mark_block_nesting
PARAMS ((struct nesting
*));
425 static void mark_case_nesting
PARAMS ((struct nesting
*));
426 static void mark_case_node
PARAMS ((struct case_node
*));
427 static void mark_goto_fixup
PARAMS ((struct goto_fixup
*));
428 static void free_case_nodes
PARAMS ((case_node_ptr
));
431 using_eh_for_cleanups ()
433 using_eh_for_cleanups_p
= 1;
436 /* Mark N (known to be a cond-nesting) for GC. */
439 mark_cond_nesting (n
)
444 ggc_mark_rtx (n
->exit_label
);
445 ggc_mark_rtx (n
->data
.cond
.endif_label
);
446 ggc_mark_rtx (n
->data
.cond
.next_label
);
452 /* Mark N (known to be a loop-nesting) for GC. */
455 mark_loop_nesting (n
)
461 ggc_mark_rtx (n
->exit_label
);
462 ggc_mark_rtx (n
->data
.loop
.start_label
);
463 ggc_mark_rtx (n
->data
.loop
.end_label
);
464 ggc_mark_rtx (n
->data
.loop
.alt_end_label
);
465 ggc_mark_rtx (n
->data
.loop
.continue_label
);
471 /* Mark N (known to be a block-nesting) for GC. */
474 mark_block_nesting (n
)
479 struct label_chain
*l
;
481 ggc_mark_rtx (n
->exit_label
);
482 ggc_mark_rtx (n
->data
.block
.stack_level
);
483 ggc_mark_rtx (n
->data
.block
.first_insn
);
484 ggc_mark_tree (n
->data
.block
.cleanups
);
485 ggc_mark_tree (n
->data
.block
.outer_cleanups
);
487 for (l
= n
->data
.block
.label_chain
; l
!= NULL
; l
= l
->next
)
490 ggc_mark_tree (l
->label
);
493 ggc_mark_rtx (n
->data
.block
.last_unconditional_cleanup
);
495 /* ??? cleanup_ptr never points outside the stack, does it? */
501 /* Mark N (known to be a case-nesting) for GC. */
504 mark_case_nesting (n
)
509 ggc_mark_rtx (n
->exit_label
);
510 ggc_mark_rtx (n
->data
.case_stmt
.start
);
512 ggc_mark_tree (n
->data
.case_stmt
.default_label
);
513 ggc_mark_tree (n
->data
.case_stmt
.index_expr
);
514 ggc_mark_tree (n
->data
.case_stmt
.nominal_type
);
516 mark_case_node (n
->data
.case_stmt
.case_list
);
529 ggc_mark_tree (c
->low
);
530 ggc_mark_tree (c
->high
);
531 ggc_mark_tree (c
->code_label
);
533 mark_case_node (c
->right
);
534 mark_case_node (c
->left
);
542 struct goto_fixup
*g
;
547 ggc_mark_rtx (g
->before_jump
);
548 ggc_mark_tree (g
->target
);
549 ggc_mark_tree (g
->context
);
550 ggc_mark_rtx (g
->target_rtl
);
551 ggc_mark_rtx (g
->stack_level
);
552 ggc_mark_tree (g
->cleanup_list_list
);
558 /* Clear out all parts of the state in F that can safely be discarded
559 after the function has been compiled, to let garbage collection
560 reclaim the memory. */
566 /* We're about to free the function obstack. If we hold pointers to
567 things allocated there, then we'll try to mark them when we do
568 GC. So, we clear them out here explicitly. */
578 struct stmt_status
*p
;
583 mark_block_nesting (p
->x_block_stack
);
584 mark_cond_nesting (p
->x_cond_stack
);
585 mark_loop_nesting (p
->x_loop_stack
);
586 mark_case_nesting (p
->x_case_stack
);
588 ggc_mark_tree (p
->x_last_expr_type
);
589 /* last_epxr_value is only valid if last_expr_type is nonzero. */
590 if (p
->x_last_expr_type
)
591 ggc_mark_rtx (p
->x_last_expr_value
);
593 mark_goto_fixup (p
->x_goto_fixup_chain
);
599 gcc_obstack_init (&stmt_obstack
);
603 init_stmt_for_function ()
605 cfun
->stmt
= (struct stmt_status
*) xmalloc (sizeof (struct stmt_status
));
607 /* We are not currently within any block, conditional, loop or case. */
609 stack_block_stack
= 0;
616 current_block_start_count
= 0;
618 /* No gotos have been expanded yet. */
619 goto_fixup_chain
= 0;
621 /* We are not processing a ({...}) grouping. */
622 expr_stmts_for_value
= 0;
624 last_expr_value
= NULL_RTX
;
627 /* Return nonzero if anything is pushed on the loop, condition, or case
632 return cond_stack
|| loop_stack
|| case_stack
;
635 /* Record the current file and line. Called from emit_line_note. */
637 set_file_and_line_for_stmt (file
, line
)
641 /* If we're outputting an inline function, and we add a line note,
642 there may be no CFUN->STMT information. So, there's no need to
646 emit_filename
= file
;
651 /* Emit a no-op instruction. */
658 last_insn
= get_last_insn ();
660 && (GET_CODE (last_insn
) == CODE_LABEL
661 || (GET_CODE (last_insn
) == NOTE
662 && prev_real_insn (last_insn
) == 0)))
663 emit_insn (gen_nop ());
666 /* Return the rtx-label that corresponds to a LABEL_DECL,
667 creating it if necessary. */
673 if (TREE_CODE (label
) != LABEL_DECL
)
676 if (!DECL_RTL_SET_P (label
))
677 SET_DECL_RTL (label
, gen_label_rtx ());
679 return DECL_RTL (label
);
683 /* Add an unconditional jump to LABEL as the next sequential instruction. */
689 do_pending_stack_adjust ();
690 emit_jump_insn (gen_jump (label
));
694 /* Emit code to jump to the address
695 specified by the pointer expression EXP. */
698 expand_computed_goto (exp
)
701 rtx x
= expand_expr (exp
, NULL_RTX
, VOIDmode
, 0);
703 #ifdef POINTERS_EXTEND_UNSIGNED
704 x
= convert_memory_address (Pmode
, x
);
708 /* Be sure the function is executable. */
709 if (current_function_check_memory_usage
)
710 emit_library_call (chkr_check_exec_libfunc
, LCT_CONST_MAKE_BLOCK
,
711 VOIDmode
, 1, x
, ptr_mode
);
713 do_pending_stack_adjust ();
714 emit_indirect_jump (x
);
716 current_function_has_computed_jump
= 1;
719 /* Handle goto statements and the labels that they can go to. */
721 /* Specify the location in the RTL code of a label LABEL,
722 which is a LABEL_DECL tree node.
724 This is used for the kind of label that the user can jump to with a
725 goto statement, and for alternatives of a switch or case statement.
726 RTL labels generated for loops and conditionals don't go through here;
727 they are generated directly at the RTL level, by other functions below.
729 Note that this has nothing to do with defining label *names*.
730 Languages vary in how they do that and what that even means. */
736 struct label_chain
*p
;
738 do_pending_stack_adjust ();
739 emit_label (label_rtx (label
));
740 if (DECL_NAME (label
))
741 LABEL_NAME (DECL_RTL (label
)) = IDENTIFIER_POINTER (DECL_NAME (label
));
743 if (stack_block_stack
!= 0)
745 p
= (struct label_chain
*) ggc_alloc (sizeof (struct label_chain
));
746 p
->next
= stack_block_stack
->data
.block
.label_chain
;
747 stack_block_stack
->data
.block
.label_chain
= p
;
752 /* Declare that LABEL (a LABEL_DECL) may be used for nonlocal gotos
753 from nested functions. */
756 declare_nonlocal_label (label
)
759 rtx slot
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
761 nonlocal_labels
= tree_cons (NULL_TREE
, label
, nonlocal_labels
);
762 LABEL_PRESERVE_P (label_rtx (label
)) = 1;
763 if (nonlocal_goto_handler_slots
== 0)
765 emit_stack_save (SAVE_NONLOCAL
,
766 &nonlocal_goto_stack_level
,
767 PREV_INSN (tail_recursion_reentry
));
769 nonlocal_goto_handler_slots
770 = gen_rtx_EXPR_LIST (VOIDmode
, slot
, nonlocal_goto_handler_slots
);
773 /* Generate RTL code for a `goto' statement with target label LABEL.
774 LABEL should be a LABEL_DECL tree node that was or will later be
775 defined with `expand_label'. */
783 /* Check for a nonlocal goto to a containing function. */
784 context
= decl_function_context (label
);
785 if (context
!= 0 && context
!= current_function_decl
)
787 struct function
*p
= find_function_data (context
);
788 rtx label_ref
= gen_rtx_LABEL_REF (Pmode
, label_rtx (label
));
789 rtx handler_slot
, static_chain
, save_area
, insn
;
792 /* Find the corresponding handler slot for this label. */
793 handler_slot
= p
->x_nonlocal_goto_handler_slots
;
794 for (link
= p
->x_nonlocal_labels
; TREE_VALUE (link
) != label
;
795 link
= TREE_CHAIN (link
))
796 handler_slot
= XEXP (handler_slot
, 1);
797 handler_slot
= XEXP (handler_slot
, 0);
799 p
->has_nonlocal_label
= 1;
800 current_function_has_nonlocal_goto
= 1;
801 LABEL_REF_NONLOCAL_P (label_ref
) = 1;
803 /* Copy the rtl for the slots so that they won't be shared in
804 case the virtual stack vars register gets instantiated differently
805 in the parent than in the child. */
807 static_chain
= copy_to_reg (lookup_static_chain (label
));
809 /* Get addr of containing function's current nonlocal goto handler,
810 which will do any cleanups and then jump to the label. */
811 handler_slot
= copy_to_reg (replace_rtx (copy_rtx (handler_slot
),
812 virtual_stack_vars_rtx
,
815 /* Get addr of containing function's nonlocal save area. */
816 save_area
= p
->x_nonlocal_goto_stack_level
;
818 save_area
= replace_rtx (copy_rtx (save_area
),
819 virtual_stack_vars_rtx
, static_chain
);
821 #if HAVE_nonlocal_goto
822 if (HAVE_nonlocal_goto
)
823 emit_insn (gen_nonlocal_goto (static_chain
, handler_slot
,
824 save_area
, label_ref
));
828 /* Restore frame pointer for containing function.
829 This sets the actual hard register used for the frame pointer
830 to the location of the function's incoming static chain info.
831 The non-local goto handler will then adjust it to contain the
832 proper value and reload the argument pointer, if needed. */
833 emit_move_insn (hard_frame_pointer_rtx
, static_chain
);
834 emit_stack_restore (SAVE_NONLOCAL
, save_area
, NULL_RTX
);
836 /* USE of hard_frame_pointer_rtx added for consistency;
837 not clear if really needed. */
838 emit_insn (gen_rtx_USE (VOIDmode
, hard_frame_pointer_rtx
));
839 emit_insn (gen_rtx_USE (VOIDmode
, stack_pointer_rtx
));
840 emit_indirect_jump (handler_slot
);
843 /* Search backwards to the jump insn and mark it as a
845 for (insn
= get_last_insn ();
846 GET_CODE (insn
) != JUMP_INSN
;
847 insn
= PREV_INSN (insn
))
849 REG_NOTES (insn
) = alloc_EXPR_LIST (REG_NON_LOCAL_GOTO
, const0_rtx
,
853 expand_goto_internal (label
, label_rtx (label
), NULL_RTX
);
856 /* Generate RTL code for a `goto' statement with target label BODY.
857 LABEL should be a LABEL_REF.
858 LAST_INSN, if non-0, is the rtx we should consider as the last
859 insn emitted (for the purposes of cleaning up a return). */
862 expand_goto_internal (body
, label
, last_insn
)
867 struct nesting
*block
;
870 if (GET_CODE (label
) != CODE_LABEL
)
873 /* If label has already been defined, we can tell now
874 whether and how we must alter the stack level. */
876 if (PREV_INSN (label
) != 0)
878 /* Find the innermost pending block that contains the label.
879 (Check containment by comparing insn-uids.)
880 Then restore the outermost stack level within that block,
881 and do cleanups of all blocks contained in it. */
882 for (block
= block_stack
; block
; block
= block
->next
)
884 if (INSN_UID (block
->data
.block
.first_insn
) < INSN_UID (label
))
886 if (block
->data
.block
.stack_level
!= 0)
887 stack_level
= block
->data
.block
.stack_level
;
888 /* Execute the cleanups for blocks we are exiting. */
889 if (block
->data
.block
.cleanups
!= 0)
891 expand_cleanups (block
->data
.block
.cleanups
, NULL_TREE
, 1, 1);
892 do_pending_stack_adjust ();
898 /* Ensure stack adjust isn't done by emit_jump, as this
899 would clobber the stack pointer. This one should be
900 deleted as dead by flow. */
901 clear_pending_stack_adjust ();
902 do_pending_stack_adjust ();
904 /* Don't do this adjust if it's to the end label and this function
905 is to return with a depressed stack pointer. */
906 if (label
== return_label
907 && (((TREE_CODE (TREE_TYPE (current_function_decl
))
909 && (TYPE_RETURNS_STACK_DEPRESSED
910 (TREE_TYPE (current_function_decl
))))))
913 emit_stack_restore (SAVE_BLOCK
, stack_level
, NULL_RTX
);
916 if (body
!= 0 && DECL_TOO_LATE (body
))
917 error ("jump to `%s' invalidly jumps into binding contour",
918 IDENTIFIER_POINTER (DECL_NAME (body
)));
920 /* Label not yet defined: may need to put this goto
921 on the fixup list. */
922 else if (! expand_fixup (body
, label
, last_insn
))
924 /* No fixup needed. Record that the label is the target
925 of at least one goto that has no fixup. */
927 TREE_ADDRESSABLE (body
) = 1;
933 /* Generate if necessary a fixup for a goto
934 whose target label in tree structure (if any) is TREE_LABEL
935 and whose target in rtl is RTL_LABEL.
937 If LAST_INSN is nonzero, we pretend that the jump appears
938 after insn LAST_INSN instead of at the current point in the insn stream.
940 The fixup will be used later to insert insns just before the goto.
941 Those insns will restore the stack level as appropriate for the
942 target label, and will (in the case of C++) also invoke any object
943 destructors which have to be invoked when we exit the scopes which
944 are exited by the goto.
946 Value is nonzero if a fixup is made. */
949 expand_fixup (tree_label
, rtl_label
, last_insn
)
954 struct nesting
*block
, *end_block
;
956 /* See if we can recognize which block the label will be output in.
957 This is possible in some very common cases.
958 If we succeed, set END_BLOCK to that block.
959 Otherwise, set it to 0. */
962 && (rtl_label
== cond_stack
->data
.cond
.endif_label
963 || rtl_label
== cond_stack
->data
.cond
.next_label
))
964 end_block
= cond_stack
;
965 /* If we are in a loop, recognize certain labels which
966 are likely targets. This reduces the number of fixups
967 we need to create. */
969 && (rtl_label
== loop_stack
->data
.loop
.start_label
970 || rtl_label
== loop_stack
->data
.loop
.end_label
971 || rtl_label
== loop_stack
->data
.loop
.continue_label
))
972 end_block
= loop_stack
;
976 /* Now set END_BLOCK to the binding level to which we will return. */
980 struct nesting
*next_block
= end_block
->all
;
983 /* First see if the END_BLOCK is inside the innermost binding level.
984 If so, then no cleanups or stack levels are relevant. */
985 while (next_block
&& next_block
!= block
)
986 next_block
= next_block
->all
;
991 /* Otherwise, set END_BLOCK to the innermost binding level
992 which is outside the relevant control-structure nesting. */
993 next_block
= block_stack
->next
;
994 for (block
= block_stack
; block
!= end_block
; block
= block
->all
)
995 if (block
== next_block
)
996 next_block
= next_block
->next
;
997 end_block
= next_block
;
1000 /* Does any containing block have a stack level or cleanups?
1001 If not, no fixup is needed, and that is the normal case
1002 (the only case, for standard C). */
1003 for (block
= block_stack
; block
!= end_block
; block
= block
->next
)
1004 if (block
->data
.block
.stack_level
!= 0
1005 || block
->data
.block
.cleanups
!= 0)
1008 if (block
!= end_block
)
1010 /* Ok, a fixup is needed. Add a fixup to the list of such. */
1011 struct goto_fixup
*fixup
1012 = (struct goto_fixup
*) ggc_alloc (sizeof (struct goto_fixup
));
1013 /* In case an old stack level is restored, make sure that comes
1014 after any pending stack adjust. */
1015 /* ?? If the fixup isn't to come at the present position,
1016 doing the stack adjust here isn't useful. Doing it with our
1017 settings at that location isn't useful either. Let's hope
1020 do_pending_stack_adjust ();
1021 fixup
->target
= tree_label
;
1022 fixup
->target_rtl
= rtl_label
;
1024 /* Create a BLOCK node and a corresponding matched set of
1025 NOTE_INSN_BLOCK_BEG and NOTE_INSN_BLOCK_END notes at
1026 this point. The notes will encapsulate any and all fixup
1027 code which we might later insert at this point in the insn
1028 stream. Also, the BLOCK node will be the parent (i.e. the
1029 `SUPERBLOCK') of any other BLOCK nodes which we might create
1030 later on when we are expanding the fixup code.
1032 Note that optimization passes (including expand_end_loop)
1033 might move the *_BLOCK notes away, so we use a NOTE_INSN_DELETED
1034 as a placeholder. */
1037 register rtx original_before_jump
1038 = last_insn
? last_insn
: get_last_insn ();
1043 block
= make_node (BLOCK
);
1044 TREE_USED (block
) = 1;
1046 if (!cfun
->x_whole_function_mode_p
)
1047 insert_block (block
);
1051 = BLOCK_CHAIN (DECL_INITIAL (current_function_decl
));
1052 BLOCK_CHAIN (DECL_INITIAL (current_function_decl
))
1057 start
= emit_note (NULL_PTR
, NOTE_INSN_BLOCK_BEG
);
1058 if (cfun
->x_whole_function_mode_p
)
1059 NOTE_BLOCK (start
) = block
;
1060 fixup
->before_jump
= emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
1061 end
= emit_note (NULL_PTR
, NOTE_INSN_BLOCK_END
);
1062 if (cfun
->x_whole_function_mode_p
)
1063 NOTE_BLOCK (end
) = block
;
1064 fixup
->context
= block
;
1066 emit_insns_after (start
, original_before_jump
);
1069 fixup
->block_start_count
= current_block_start_count
;
1070 fixup
->stack_level
= 0;
1071 fixup
->cleanup_list_list
1072 = ((block
->data
.block
.outer_cleanups
1073 || block
->data
.block
.cleanups
)
1074 ? tree_cons (NULL_TREE
, block
->data
.block
.cleanups
,
1075 block
->data
.block
.outer_cleanups
)
1077 fixup
->next
= goto_fixup_chain
;
1078 goto_fixup_chain
= fixup
;
1084 /* Expand any needed fixups in the outputmost binding level of the
1085 function. FIRST_INSN is the first insn in the function. */
1088 expand_fixups (first_insn
)
1091 fixup_gotos (NULL_PTR
, NULL_RTX
, NULL_TREE
, first_insn
, 0);
1094 /* When exiting a binding contour, process all pending gotos requiring fixups.
1095 THISBLOCK is the structure that describes the block being exited.
1096 STACK_LEVEL is the rtx for the stack level to restore exiting this contour.
1097 CLEANUP_LIST is a list of expressions to evaluate on exiting this contour.
1098 FIRST_INSN is the insn that began this contour.
1100 Gotos that jump out of this contour must restore the
1101 stack level and do the cleanups before actually jumping.
1103 DONT_JUMP_IN nonzero means report error there is a jump into this
1104 contour from before the beginning of the contour.
1105 This is also done if STACK_LEVEL is nonzero. */
1108 fixup_gotos (thisblock
, stack_level
, cleanup_list
, first_insn
, dont_jump_in
)
1109 struct nesting
*thisblock
;
1115 register struct goto_fixup
*f
, *prev
;
1117 /* F is the fixup we are considering; PREV is the previous one. */
1118 /* We run this loop in two passes so that cleanups of exited blocks
1119 are run first, and blocks that are exited are marked so
1122 for (prev
= 0, f
= goto_fixup_chain
; f
; prev
= f
, f
= f
->next
)
1124 /* Test for a fixup that is inactive because it is already handled. */
1125 if (f
->before_jump
== 0)
1127 /* Delete inactive fixup from the chain, if that is easy to do. */
1129 prev
->next
= f
->next
;
1131 /* Has this fixup's target label been defined?
1132 If so, we can finalize it. */
1133 else if (PREV_INSN (f
->target_rtl
) != 0)
1135 register rtx cleanup_insns
;
1137 /* If this fixup jumped into this contour from before the beginning
1138 of this contour, report an error. This code used to use
1139 the first non-label insn after f->target_rtl, but that's
1140 wrong since such can be added, by things like put_var_into_stack
1141 and have INSN_UIDs that are out of the range of the block. */
1142 /* ??? Bug: this does not detect jumping in through intermediate
1143 blocks that have stack levels or cleanups.
1144 It detects only a problem with the innermost block
1145 around the label. */
1147 && (dont_jump_in
|| stack_level
|| cleanup_list
)
1148 && INSN_UID (first_insn
) < INSN_UID (f
->target_rtl
)
1149 && INSN_UID (first_insn
) > INSN_UID (f
->before_jump
)
1150 && ! DECL_ERROR_ISSUED (f
->target
))
1152 error_with_decl (f
->target
,
1153 "label `%s' used before containing binding contour");
1154 /* Prevent multiple errors for one label. */
1155 DECL_ERROR_ISSUED (f
->target
) = 1;
1158 /* We will expand the cleanups into a sequence of their own and
1159 then later on we will attach this new sequence to the insn
1160 stream just ahead of the actual jump insn. */
1164 /* Temporarily restore the lexical context where we will
1165 logically be inserting the fixup code. We do this for the
1166 sake of getting the debugging information right. */
1169 set_block (f
->context
);
1171 /* Expand the cleanups for blocks this jump exits. */
1172 if (f
->cleanup_list_list
)
1175 for (lists
= f
->cleanup_list_list
; lists
; lists
= TREE_CHAIN (lists
))
1176 /* Marked elements correspond to blocks that have been closed.
1177 Do their cleanups. */
1178 if (TREE_ADDRESSABLE (lists
)
1179 && TREE_VALUE (lists
) != 0)
1181 expand_cleanups (TREE_VALUE (lists
), NULL_TREE
, 1, 1);
1182 /* Pop any pushes done in the cleanups,
1183 in case function is about to return. */
1184 do_pending_stack_adjust ();
1188 /* Restore stack level for the biggest contour that this
1189 jump jumps out of. */
1191 && ! (f
->target_rtl
== return_label
1192 && ((TREE_CODE (TREE_TYPE (current_function_decl
))
1194 && (TYPE_RETURNS_STACK_DEPRESSED
1195 (TREE_TYPE (current_function_decl
))))))
1196 emit_stack_restore (SAVE_BLOCK
, f
->stack_level
, f
->before_jump
);
1198 /* Finish up the sequence containing the insns which implement the
1199 necessary cleanups, and then attach that whole sequence to the
1200 insn stream just ahead of the actual jump insn. Attaching it
1201 at that point insures that any cleanups which are in fact
1202 implicit C++ object destructions (which must be executed upon
1203 leaving the block) appear (to the debugger) to be taking place
1204 in an area of the generated code where the object(s) being
1205 destructed are still "in scope". */
1207 cleanup_insns
= get_insns ();
1211 emit_insns_after (cleanup_insns
, f
->before_jump
);
1217 /* For any still-undefined labels, do the cleanups for this block now.
1218 We must do this now since items in the cleanup list may go out
1219 of scope when the block ends. */
1220 for (prev
= 0, f
= goto_fixup_chain
; f
; prev
= f
, f
= f
->next
)
1221 if (f
->before_jump
!= 0
1222 && PREV_INSN (f
->target_rtl
) == 0
1223 /* Label has still not appeared. If we are exiting a block with
1224 a stack level to restore, that started before the fixup,
1225 mark this stack level as needing restoration
1226 when the fixup is later finalized. */
1228 /* Note: if THISBLOCK == 0 and we have a label that hasn't appeared, it
1229 means the label is undefined. That's erroneous, but possible. */
1230 && (thisblock
->data
.block
.block_start_count
1231 <= f
->block_start_count
))
1233 tree lists
= f
->cleanup_list_list
;
1236 for (; lists
; lists
= TREE_CHAIN (lists
))
1237 /* If the following elt. corresponds to our containing block
1238 then the elt. must be for this block. */
1239 if (TREE_CHAIN (lists
) == thisblock
->data
.block
.outer_cleanups
)
1243 set_block (f
->context
);
1244 expand_cleanups (TREE_VALUE (lists
), NULL_TREE
, 1, 1);
1245 do_pending_stack_adjust ();
1246 cleanup_insns
= get_insns ();
1249 if (cleanup_insns
!= 0)
1251 = emit_insns_after (cleanup_insns
, f
->before_jump
);
1253 f
->cleanup_list_list
= TREE_CHAIN (lists
);
1257 f
->stack_level
= stack_level
;
1261 /* Return the number of times character C occurs in string S. */
1263 n_occurrences (c
, s
)
1273 /* Generate RTL for an asm statement (explicit assembler code).
1274 BODY is a STRING_CST node containing the assembler code text,
1275 or an ADDR_EXPR containing a STRING_CST. */
1281 if (current_function_check_memory_usage
)
1283 error ("`asm' cannot be used in function where memory usage is checked");
1287 if (TREE_CODE (body
) == ADDR_EXPR
)
1288 body
= TREE_OPERAND (body
, 0);
1290 emit_insn (gen_rtx_ASM_INPUT (VOIDmode
,
1291 TREE_STRING_POINTER (body
)));
1295 /* Generate RTL for an asm statement with arguments.
1296 STRING is the instruction template.
1297 OUTPUTS is a list of output arguments (lvalues); INPUTS a list of inputs.
1298 Each output or input has an expression in the TREE_VALUE and
1299 a constraint-string in the TREE_PURPOSE.
1300 CLOBBERS is a list of STRING_CST nodes each naming a hard register
1301 that is clobbered by this insn.
1303 Not all kinds of lvalue that may appear in OUTPUTS can be stored directly.
1304 Some elements of OUTPUTS may be replaced with trees representing temporary
1305 values. The caller should copy those temporary values to the originally
1308 VOL nonzero means the insn is volatile; don't optimize it. */
1311 expand_asm_operands (string
, outputs
, inputs
, clobbers
, vol
, filename
, line
)
1312 tree string
, outputs
, inputs
, clobbers
;
1314 const char *filename
;
1317 rtvec argvec
, constraints
;
1319 int ninputs
= list_length (inputs
);
1320 int noutputs
= list_length (outputs
);
1325 /* Vector of RTX's of evaluated output operands. */
1326 rtx
*output_rtx
= (rtx
*) alloca (noutputs
* sizeof (rtx
));
1327 int *inout_opnum
= (int *) alloca (noutputs
* sizeof (int));
1328 rtx
*real_output_rtx
= (rtx
*) alloca (noutputs
* sizeof (rtx
));
1329 enum machine_mode
*inout_mode
1330 = (enum machine_mode
*) alloca (noutputs
* sizeof (enum machine_mode
));
1331 /* The insn we have emitted. */
1333 int old_generating_concat_p
= generating_concat_p
;
1335 /* An ASM with no outputs needs to be treated as volatile, for now. */
1339 if (current_function_check_memory_usage
)
1341 error ("`asm' cannot be used with `-fcheck-memory-usage'");
1345 #ifdef MD_ASM_CLOBBERS
1346 /* Sometimes we wish to automatically clobber registers across an asm.
1347 Case in point is when the i386 backend moved from cc0 to a hard reg --
1348 maintaining source-level compatability means automatically clobbering
1349 the flags register. */
1350 MD_ASM_CLOBBERS (clobbers
);
1353 if (current_function_check_memory_usage
)
1355 error ("`asm' cannot be used in function where memory usage is checked");
1359 /* Count the number of meaningful clobbered registers, ignoring what
1360 we would ignore later. */
1362 for (tail
= clobbers
; tail
; tail
= TREE_CHAIN (tail
))
1364 const char *regname
= TREE_STRING_POINTER (TREE_VALUE (tail
));
1366 i
= decode_reg_name (regname
);
1367 if (i
>= 0 || i
== -4)
1370 error ("unknown register name `%s' in `asm'", regname
);
1375 /* Check that the number of alternatives is constant across all
1377 if (outputs
|| inputs
)
1379 tree tmp
= TREE_PURPOSE (outputs
? outputs
: inputs
);
1380 int nalternatives
= n_occurrences (',', TREE_STRING_POINTER (tmp
));
1383 if (nalternatives
+ 1 > MAX_RECOG_ALTERNATIVES
)
1385 error ("too many alternatives in `asm'");
1392 const char *constraint
= TREE_STRING_POINTER (TREE_PURPOSE (tmp
));
1394 if (n_occurrences (',', constraint
) != nalternatives
)
1396 error ("operand constraints for `asm' differ in number of alternatives");
1400 if (TREE_CHAIN (tmp
))
1401 tmp
= TREE_CHAIN (tmp
);
1403 tmp
= next
, next
= 0;
1407 for (i
= 0, tail
= outputs
; tail
; tail
= TREE_CHAIN (tail
), i
++)
1409 tree val
= TREE_VALUE (tail
);
1410 tree type
= TREE_TYPE (val
);
1411 const char *constraint
;
1419 /* If there's an erroneous arg, emit no insn. */
1420 if (TREE_TYPE (val
) == error_mark_node
)
1423 /* Make sure constraint has `=' and does not have `+'. Also, see
1424 if it allows any register. Be liberal on the latter test, since
1425 the worst that happens if we get it wrong is we issue an error
1428 constraint
= TREE_STRING_POINTER (TREE_PURPOSE (tail
));
1429 c_len
= strlen (constraint
);
1431 /* Allow the `=' or `+' to not be at the beginning of the string,
1432 since it wasn't explicitly documented that way, and there is a
1433 large body of code that puts it last. Swap the character to
1434 the front, so as not to uglify any place else. */
1438 if ((p
= strchr (constraint
, '=')) != NULL
)
1440 if ((p
= strchr (constraint
, '+')) != NULL
)
1443 error ("output operand constraint lacks `='");
1447 is_inout
= *p
== '+';
1451 /* Have to throw away this constraint string and get a new one. */
1452 char *buf
= alloca (c_len
+ 1);
1455 memcpy (buf
+ 1, constraint
, j
);
1456 memcpy (buf
+ 1 + j
, p
+ 1, c_len
- j
); /* not -j-1 - copy null */
1457 constraint
= ggc_alloc_string (buf
, c_len
);
1461 "output constraint `%c' for operand %d is not at the beginning",
1465 /* Make sure we can specify the matching operand. */
1466 if (is_inout
&& i
> 9)
1468 error ("output operand constraint %d contains `+'", i
);
1472 for (j
= 1; j
< c_len
; j
++)
1473 switch (constraint
[j
])
1477 error ("operand constraint contains '+' or '=' at illegal position.");
1481 if (i
+ 1 == ninputs
+ noutputs
)
1483 error ("`%%' constraint used with last operand");
1488 case '?': case '!': case '*': case '&': case '#':
1489 case 'E': case 'F': case 'G': case 'H':
1490 case 's': case 'i': case 'n':
1491 case 'I': case 'J': case 'K': case 'L': case 'M':
1492 case 'N': case 'O': case 'P': case ',':
1495 case '0': case '1': case '2': case '3': case '4':
1496 case '5': case '6': case '7': case '8': case '9':
1497 error ("matching constraint not valid in output operand");
1500 case 'V': case 'm': case 'o':
1505 /* ??? Before flow, auto inc/dec insns are not supposed to exist,
1506 excepting those that expand_call created. So match memory
1521 if (! ISALPHA (constraint
[j
]))
1523 error ("invalid punctuation `%c' in constraint",
1527 if (REG_CLASS_FROM_LETTER (constraint
[j
]) != NO_REGS
)
1529 #ifdef EXTRA_CONSTRAINT
1532 /* Otherwise we can't assume anything about the nature of
1533 the constraint except that it isn't purely registers.
1534 Treat it like "g" and hope for the best. */
1542 /* If an output operand is not a decl or indirect ref and our constraint
1543 allows a register, make a temporary to act as an intermediate.
1544 Make the asm insn write into that, then our caller will copy it to
1545 the real output operand. Likewise for promoted variables. */
1547 generating_concat_p
= 0;
1549 real_output_rtx
[i
] = NULL_RTX
;
1550 if ((TREE_CODE (val
) == INDIRECT_REF
1553 && (allows_mem
|| GET_CODE (DECL_RTL (val
)) == REG
)
1554 && ! (GET_CODE (DECL_RTL (val
)) == REG
1555 && GET_MODE (DECL_RTL (val
)) != TYPE_MODE (type
)))
1560 mark_addressable (TREE_VALUE (tail
));
1563 = expand_expr (TREE_VALUE (tail
), NULL_RTX
, VOIDmode
,
1564 EXPAND_MEMORY_USE_WO
);
1566 if (! allows_reg
&& GET_CODE (output_rtx
[i
]) != MEM
)
1567 error ("output number %d not directly addressable", i
);
1568 if ((! allows_mem
&& GET_CODE (output_rtx
[i
]) == MEM
)
1569 || GET_CODE (output_rtx
[i
]) == CONCAT
)
1571 real_output_rtx
[i
] = protect_from_queue (output_rtx
[i
], 1);
1572 output_rtx
[i
] = gen_reg_rtx (GET_MODE (output_rtx
[i
]));
1574 emit_move_insn (output_rtx
[i
], real_output_rtx
[i
]);
1579 output_rtx
[i
] = assign_temp (type
, 0, 0, 1);
1580 TREE_VALUE (tail
) = make_tree (type
, output_rtx
[i
]);
1583 generating_concat_p
= old_generating_concat_p
;
1587 inout_mode
[ninout
] = TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
)));
1588 inout_opnum
[ninout
++] = i
;
1593 if (ninputs
+ noutputs
> MAX_RECOG_OPERANDS
)
1595 error ("more than %d operands in `asm'", MAX_RECOG_OPERANDS
);
1599 /* Make vectors for the expression-rtx and constraint strings. */
1601 argvec
= rtvec_alloc (ninputs
);
1602 constraints
= rtvec_alloc (ninputs
);
1604 body
= gen_rtx_ASM_OPERANDS ((noutputs
== 0 ? VOIDmode
1605 : GET_MODE (output_rtx
[0])),
1606 TREE_STRING_POINTER (string
),
1607 empty_string
, 0, argvec
, constraints
,
1610 MEM_VOLATILE_P (body
) = vol
;
1612 /* Eval the inputs and put them into ARGVEC.
1613 Put their constraints into ASM_INPUTs and store in CONSTRAINTS. */
1616 for (tail
= inputs
; tail
; tail
= TREE_CHAIN (tail
))
1619 int allows_reg
= 0, allows_mem
= 0;
1620 const char *constraint
, *orig_constraint
;
1624 /* If there's an erroneous arg, emit no insn,
1625 because the ASM_INPUT would get VOIDmode
1626 and that could cause a crash in reload. */
1627 if (TREE_TYPE (TREE_VALUE (tail
)) == error_mark_node
)
1630 /* ??? Can this happen, and does the error message make any sense? */
1631 if (TREE_PURPOSE (tail
) == NULL_TREE
)
1633 error ("hard register `%s' listed as input operand to `asm'",
1634 TREE_STRING_POINTER (TREE_VALUE (tail
)) );
1638 constraint
= TREE_STRING_POINTER (TREE_PURPOSE (tail
));
1639 c_len
= strlen (constraint
);
1640 orig_constraint
= constraint
;
1642 /* Make sure constraint has neither `=', `+', nor '&'. */
1644 for (j
= 0; j
< c_len
; j
++)
1645 switch (constraint
[j
])
1647 case '+': case '=': case '&':
1648 if (constraint
== orig_constraint
)
1650 error ("input operand constraint contains `%c'",
1657 if (constraint
== orig_constraint
1658 && i
+ 1 == ninputs
- ninout
)
1660 error ("`%%' constraint used with last operand");
1665 case 'V': case 'm': case 'o':
1670 case '?': case '!': case '*': case '#':
1671 case 'E': case 'F': case 'G': case 'H':
1672 case 's': case 'i': case 'n':
1673 case 'I': case 'J': case 'K': case 'L': case 'M':
1674 case 'N': case 'O': case 'P': case ',':
1677 /* Whether or not a numeric constraint allows a register is
1678 decided by the matching constraint, and so there is no need
1679 to do anything special with them. We must handle them in
1680 the default case, so that we don't unnecessarily force
1681 operands to memory. */
1682 case '0': case '1': case '2': case '3': case '4':
1683 case '5': case '6': case '7': case '8': case '9':
1684 if (constraint
[j
] >= '0' + noutputs
)
1687 ("matching constraint references invalid operand number");
1691 /* Try and find the real constraint for this dup. */
1692 if ((j
== 0 && c_len
== 1)
1693 || (j
== 1 && c_len
== 2 && constraint
[0] == '%'))
1697 for (j
= constraint
[j
] - '0'; j
> 0; --j
)
1700 constraint
= TREE_STRING_POINTER (TREE_PURPOSE (o
));
1701 c_len
= strlen (constraint
);
1718 if (! ISALPHA (constraint
[j
]))
1720 error ("invalid punctuation `%c' in constraint",
1724 if (REG_CLASS_FROM_LETTER (constraint
[j
]) != NO_REGS
)
1726 #ifdef EXTRA_CONSTRAINT
1729 /* Otherwise we can't assume anything about the nature of
1730 the constraint except that it isn't purely registers.
1731 Treat it like "g" and hope for the best. */
1739 if (! allows_reg
&& allows_mem
)
1740 mark_addressable (TREE_VALUE (tail
));
1742 op
= expand_expr (TREE_VALUE (tail
), NULL_RTX
, VOIDmode
, 0);
1744 /* Never pass a CONCAT to an ASM. */
1745 generating_concat_p
= 0;
1746 if (GET_CODE (op
) == CONCAT
)
1747 op
= force_reg (GET_MODE (op
), op
);
1749 if (asm_operand_ok (op
, constraint
) <= 0)
1752 op
= force_reg (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
))), op
);
1753 else if (!allows_mem
)
1754 warning ("asm operand %d probably doesn't match constraints", i
);
1755 else if (CONSTANT_P (op
))
1756 op
= force_const_mem (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
))),
1758 else if (GET_CODE (op
) == REG
1759 || GET_CODE (op
) == SUBREG
1760 || GET_CODE (op
) == CONCAT
)
1762 tree type
= TREE_TYPE (TREE_VALUE (tail
));
1763 tree qual_type
= build_qualified_type (type
,
1765 | TYPE_QUAL_CONST
));
1766 rtx memloc
= assign_temp (qual_type
, 1, 1, 1);
1768 emit_move_insn (memloc
, op
);
1772 else if (GET_CODE (op
) == MEM
&& MEM_VOLATILE_P (op
))
1773 /* We won't recognize volatile memory as available a
1774 memory_operand at this point. Ignore it. */
1776 else if (queued_subexp_p (op
))
1779 /* ??? Leave this only until we have experience with what
1780 happens in combine and elsewhere when constraints are
1782 warning ("asm operand %d probably doesn't match constraints", i
);
1784 generating_concat_p
= old_generating_concat_p
;
1785 ASM_OPERANDS_INPUT (body
, i
) = op
;
1787 ASM_OPERANDS_INPUT_CONSTRAINT_EXP (body
, i
)
1788 = gen_rtx_ASM_INPUT (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
))),
1793 /* Protect all the operands from the queue now that they have all been
1796 generating_concat_p
= 0;
1798 for (i
= 0; i
< ninputs
- ninout
; i
++)
1799 ASM_OPERANDS_INPUT (body
, i
)
1800 = protect_from_queue (ASM_OPERANDS_INPUT (body
, i
), 0);
1802 for (i
= 0; i
< noutputs
; i
++)
1803 output_rtx
[i
] = protect_from_queue (output_rtx
[i
], 1);
1805 /* For in-out operands, copy output rtx to input rtx. */
1806 for (i
= 0; i
< ninout
; i
++)
1808 int j
= inout_opnum
[i
];
1810 ASM_OPERANDS_INPUT (body
, ninputs
- ninout
+ i
)
1812 ASM_OPERANDS_INPUT_CONSTRAINT_EXP (body
, ninputs
- ninout
+ i
)
1813 = gen_rtx_ASM_INPUT (inout_mode
[i
], digit_string (j
));
1816 generating_concat_p
= old_generating_concat_p
;
1818 /* Now, for each output, construct an rtx
1819 (set OUTPUT (asm_operands INSN OUTPUTNUMBER OUTPUTCONSTRAINT
1820 ARGVEC CONSTRAINTS))
1821 If there is more than one, put them inside a PARALLEL. */
1823 if (noutputs
== 1 && nclobbers
== 0)
1825 ASM_OPERANDS_OUTPUT_CONSTRAINT (body
)
1826 = TREE_STRING_POINTER (TREE_PURPOSE (outputs
));
1827 insn
= emit_insn (gen_rtx_SET (VOIDmode
, output_rtx
[0], body
));
1830 else if (noutputs
== 0 && nclobbers
== 0)
1832 /* No output operands: put in a raw ASM_OPERANDS rtx. */
1833 insn
= emit_insn (body
);
1844 body
= gen_rtx_PARALLEL (VOIDmode
, rtvec_alloc (num
+ nclobbers
));
1846 /* For each output operand, store a SET. */
1847 for (i
= 0, tail
= outputs
; tail
; tail
= TREE_CHAIN (tail
), i
++)
1849 XVECEXP (body
, 0, i
)
1850 = gen_rtx_SET (VOIDmode
,
1852 gen_rtx_ASM_OPERANDS
1853 (GET_MODE (output_rtx
[i
]),
1854 TREE_STRING_POINTER (string
),
1855 TREE_STRING_POINTER (TREE_PURPOSE (tail
)),
1856 i
, argvec
, constraints
,
1859 MEM_VOLATILE_P (SET_SRC (XVECEXP (body
, 0, i
))) = vol
;
1862 /* If there are no outputs (but there are some clobbers)
1863 store the bare ASM_OPERANDS into the PARALLEL. */
1866 XVECEXP (body
, 0, i
++) = obody
;
1868 /* Store (clobber REG) for each clobbered register specified. */
1870 for (tail
= clobbers
; tail
; tail
= TREE_CHAIN (tail
))
1872 const char *regname
= TREE_STRING_POINTER (TREE_VALUE (tail
));
1873 int j
= decode_reg_name (regname
);
1877 if (j
== -3) /* `cc', which is not a register */
1880 if (j
== -4) /* `memory', don't cache memory across asm */
1882 XVECEXP (body
, 0, i
++)
1883 = gen_rtx_CLOBBER (VOIDmode
,
1886 gen_rtx_SCRATCH (VOIDmode
)));
1890 /* Ignore unknown register, error already signaled. */
1894 /* Use QImode since that's guaranteed to clobber just one reg. */
1895 XVECEXP (body
, 0, i
++)
1896 = gen_rtx_CLOBBER (VOIDmode
, gen_rtx_REG (QImode
, j
));
1899 insn
= emit_insn (body
);
1902 /* For any outputs that needed reloading into registers, spill them
1903 back to where they belong. */
1904 for (i
= 0; i
< noutputs
; ++i
)
1905 if (real_output_rtx
[i
])
1906 emit_move_insn (real_output_rtx
[i
], output_rtx
[i
]);
1911 /* Generate RTL to evaluate the expression EXP
1912 and remember it in case this is the VALUE in a ({... VALUE; }) constr. */
1915 expand_expr_stmt (exp
)
1918 /* If -W, warn about statements with no side effects,
1919 except for an explicit cast to void (e.g. for assert()), and
1920 except inside a ({...}) where they may be useful. */
1921 if (expr_stmts_for_value
== 0 && exp
!= error_mark_node
)
1923 if (! TREE_SIDE_EFFECTS (exp
))
1925 if ((extra_warnings
|| warn_unused_value
)
1926 && !(TREE_CODE (exp
) == CONVERT_EXPR
1927 && VOID_TYPE_P (TREE_TYPE (exp
))))
1928 warning_with_file_and_line (emit_filename
, emit_lineno
,
1929 "statement with no effect");
1931 else if (warn_unused_value
)
1932 warn_if_unused_value (exp
);
1935 /* If EXP is of function type and we are expanding statements for
1936 value, convert it to pointer-to-function. */
1937 if (expr_stmts_for_value
&& TREE_CODE (TREE_TYPE (exp
)) == FUNCTION_TYPE
)
1938 exp
= build1 (ADDR_EXPR
, build_pointer_type (TREE_TYPE (exp
)), exp
);
1940 /* The call to `expand_expr' could cause last_expr_type and
1941 last_expr_value to get reset. Therefore, we set last_expr_value
1942 and last_expr_type *after* calling expand_expr. */
1943 last_expr_value
= expand_expr (exp
,
1944 (expr_stmts_for_value
1945 ? NULL_RTX
: const0_rtx
),
1947 last_expr_type
= TREE_TYPE (exp
);
1949 /* If all we do is reference a volatile value in memory,
1950 copy it to a register to be sure it is actually touched. */
1951 if (last_expr_value
!= 0 && GET_CODE (last_expr_value
) == MEM
1952 && TREE_THIS_VOLATILE (exp
))
1954 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
)
1956 else if (TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
)
1957 copy_to_reg (last_expr_value
);
1960 rtx lab
= gen_label_rtx ();
1962 /* Compare the value with itself to reference it. */
1963 emit_cmp_and_jump_insns (last_expr_value
, last_expr_value
, EQ
,
1964 expand_expr (TYPE_SIZE (last_expr_type
),
1965 NULL_RTX
, VOIDmode
, 0),
1967 TYPE_ALIGN (last_expr_type
) / BITS_PER_UNIT
,
1973 /* If this expression is part of a ({...}) and is in memory, we may have
1974 to preserve temporaries. */
1975 preserve_temp_slots (last_expr_value
);
1977 /* Free any temporaries used to evaluate this expression. Any temporary
1978 used as a result of this expression will already have been preserved
1985 /* Warn if EXP contains any computations whose results are not used.
1986 Return 1 if a warning is printed; 0 otherwise. */
1989 warn_if_unused_value (exp
)
1992 if (TREE_USED (exp
))
1995 /* Don't warn about void constructs. This includes casting to void,
1996 void function calls, and statement expressions with a final cast
1998 if (VOID_TYPE_P (TREE_TYPE (exp
)))
2001 /* If this is an expression with side effects, don't warn. */
2002 if (TREE_SIDE_EFFECTS (exp
))
2005 switch (TREE_CODE (exp
))
2007 case PREINCREMENT_EXPR
:
2008 case POSTINCREMENT_EXPR
:
2009 case PREDECREMENT_EXPR
:
2010 case POSTDECREMENT_EXPR
:
2015 case METHOD_CALL_EXPR
:
2017 case TRY_CATCH_EXPR
:
2018 case WITH_CLEANUP_EXPR
:
2023 /* For a binding, warn if no side effect within it. */
2024 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2027 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2029 case TRUTH_ORIF_EXPR
:
2030 case TRUTH_ANDIF_EXPR
:
2031 /* In && or ||, warn if 2nd operand has no side effect. */
2032 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2035 if (TREE_NO_UNUSED_WARNING (exp
))
2037 if (warn_if_unused_value (TREE_OPERAND (exp
, 0)))
2039 /* Let people do `(foo (), 0)' without a warning. */
2040 if (TREE_CONSTANT (TREE_OPERAND (exp
, 1)))
2042 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2046 case NON_LVALUE_EXPR
:
2047 /* Don't warn about conversions not explicit in the user's program. */
2048 if (TREE_NO_UNUSED_WARNING (exp
))
2050 /* Assignment to a cast usually results in a cast of a modify.
2051 Don't complain about that. There can be an arbitrary number of
2052 casts before the modify, so we must loop until we find the first
2053 non-cast expression and then test to see if that is a modify. */
2055 tree tem
= TREE_OPERAND (exp
, 0);
2057 while (TREE_CODE (tem
) == CONVERT_EXPR
|| TREE_CODE (tem
) == NOP_EXPR
)
2058 tem
= TREE_OPERAND (tem
, 0);
2060 if (TREE_CODE (tem
) == MODIFY_EXPR
|| TREE_CODE (tem
) == INIT_EXPR
2061 || TREE_CODE (tem
) == CALL_EXPR
)
2067 /* Don't warn about automatic dereferencing of references, since
2068 the user cannot control it. */
2069 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (exp
, 0))) == REFERENCE_TYPE
)
2070 return warn_if_unused_value (TREE_OPERAND (exp
, 0));
2074 /* Referencing a volatile value is a side effect, so don't warn. */
2076 || TREE_CODE_CLASS (TREE_CODE (exp
)) == 'r')
2077 && TREE_THIS_VOLATILE (exp
))
2080 /* If this is an expression which has no operands, there is no value
2081 to be unused. There are no such language-independent codes,
2082 but front ends may define such. */
2083 if (TREE_CODE_CLASS (TREE_CODE (exp
)) == 'e'
2084 && TREE_CODE_LENGTH (TREE_CODE (exp
)) == 0)
2088 warning_with_file_and_line (emit_filename
, emit_lineno
,
2089 "value computed is not used");
2094 /* Clear out the memory of the last expression evaluated. */
2102 /* Begin a statement which will return a value.
2103 Return the RTL_EXPR for this statement expr.
2104 The caller must save that value and pass it to expand_end_stmt_expr. */
2107 expand_start_stmt_expr ()
2111 /* Make the RTL_EXPR node temporary, not momentary,
2112 so that rtl_expr_chain doesn't become garbage. */
2113 t
= make_node (RTL_EXPR
);
2114 do_pending_stack_adjust ();
2115 start_sequence_for_rtl_expr (t
);
2117 expr_stmts_for_value
++;
2121 /* Restore the previous state at the end of a statement that returns a value.
2122 Returns a tree node representing the statement's value and the
2123 insns to compute the value.
2125 The nodes of that expression have been freed by now, so we cannot use them.
2126 But we don't want to do that anyway; the expression has already been
2127 evaluated and now we just want to use the value. So generate a RTL_EXPR
2128 with the proper type and RTL value.
2130 If the last substatement was not an expression,
2131 return something with type `void'. */
2134 expand_end_stmt_expr (t
)
2139 if (last_expr_type
== 0)
2141 last_expr_type
= void_type_node
;
2142 last_expr_value
= const0_rtx
;
2144 else if (last_expr_value
== 0)
2145 /* There are some cases where this can happen, such as when the
2146 statement is void type. */
2147 last_expr_value
= const0_rtx
;
2148 else if (GET_CODE (last_expr_value
) != REG
&& ! CONSTANT_P (last_expr_value
))
2149 /* Remove any possible QUEUED. */
2150 last_expr_value
= protect_from_queue (last_expr_value
, 0);
2154 TREE_TYPE (t
) = last_expr_type
;
2155 RTL_EXPR_RTL (t
) = last_expr_value
;
2156 RTL_EXPR_SEQUENCE (t
) = get_insns ();
2158 rtl_expr_chain
= tree_cons (NULL_TREE
, t
, rtl_expr_chain
);
2162 /* Don't consider deleting this expr or containing exprs at tree level. */
2163 TREE_SIDE_EFFECTS (t
) = 1;
2164 /* Propagate volatility of the actual RTL expr. */
2165 TREE_THIS_VOLATILE (t
) = volatile_refs_p (last_expr_value
);
2168 expr_stmts_for_value
--;
2173 /* Generate RTL for the start of an if-then. COND is the expression
2174 whose truth should be tested.
2176 If EXITFLAG is nonzero, this conditional is visible to
2177 `exit_something'. */
2180 expand_start_cond (cond
, exitflag
)
2184 struct nesting
*thiscond
= ALLOC_NESTING ();
2186 /* Make an entry on cond_stack for the cond we are entering. */
2188 thiscond
->next
= cond_stack
;
2189 thiscond
->all
= nesting_stack
;
2190 thiscond
->depth
= ++nesting_depth
;
2191 thiscond
->data
.cond
.next_label
= gen_label_rtx ();
2192 /* Before we encounter an `else', we don't need a separate exit label
2193 unless there are supposed to be exit statements
2194 to exit this conditional. */
2195 thiscond
->exit_label
= exitflag
? gen_label_rtx () : 0;
2196 thiscond
->data
.cond
.endif_label
= thiscond
->exit_label
;
2197 cond_stack
= thiscond
;
2198 nesting_stack
= thiscond
;
2200 do_jump (cond
, thiscond
->data
.cond
.next_label
, NULL_RTX
);
2203 /* Generate RTL between then-clause and the elseif-clause
2204 of an if-then-elseif-.... */
2207 expand_start_elseif (cond
)
2210 if (cond_stack
->data
.cond
.endif_label
== 0)
2211 cond_stack
->data
.cond
.endif_label
= gen_label_rtx ();
2212 emit_jump (cond_stack
->data
.cond
.endif_label
);
2213 emit_label (cond_stack
->data
.cond
.next_label
);
2214 cond_stack
->data
.cond
.next_label
= gen_label_rtx ();
2215 do_jump (cond
, cond_stack
->data
.cond
.next_label
, NULL_RTX
);
2218 /* Generate RTL between the then-clause and the else-clause
2219 of an if-then-else. */
2222 expand_start_else ()
2224 if (cond_stack
->data
.cond
.endif_label
== 0)
2225 cond_stack
->data
.cond
.endif_label
= gen_label_rtx ();
2227 emit_jump (cond_stack
->data
.cond
.endif_label
);
2228 emit_label (cond_stack
->data
.cond
.next_label
);
2229 cond_stack
->data
.cond
.next_label
= 0; /* No more _else or _elseif calls. */
2232 /* After calling expand_start_else, turn this "else" into an "else if"
2233 by providing another condition. */
2236 expand_elseif (cond
)
2239 cond_stack
->data
.cond
.next_label
= gen_label_rtx ();
2240 do_jump (cond
, cond_stack
->data
.cond
.next_label
, NULL_RTX
);
2243 /* Generate RTL for the end of an if-then.
2244 Pop the record for it off of cond_stack. */
2249 struct nesting
*thiscond
= cond_stack
;
2251 do_pending_stack_adjust ();
2252 if (thiscond
->data
.cond
.next_label
)
2253 emit_label (thiscond
->data
.cond
.next_label
);
2254 if (thiscond
->data
.cond
.endif_label
)
2255 emit_label (thiscond
->data
.cond
.endif_label
);
2257 POPSTACK (cond_stack
);
2261 /* Generate RTL for the start of a loop. EXIT_FLAG is nonzero if this
2262 loop should be exited by `exit_something'. This is a loop for which
2263 `expand_continue' will jump to the top of the loop.
2265 Make an entry on loop_stack to record the labels associated with
2269 expand_start_loop (exit_flag
)
2272 register struct nesting
*thisloop
= ALLOC_NESTING ();
2274 /* Make an entry on loop_stack for the loop we are entering. */
2276 thisloop
->next
= loop_stack
;
2277 thisloop
->all
= nesting_stack
;
2278 thisloop
->depth
= ++nesting_depth
;
2279 thisloop
->data
.loop
.start_label
= gen_label_rtx ();
2280 thisloop
->data
.loop
.end_label
= gen_label_rtx ();
2281 thisloop
->data
.loop
.alt_end_label
= 0;
2282 thisloop
->data
.loop
.continue_label
= thisloop
->data
.loop
.start_label
;
2283 thisloop
->exit_label
= exit_flag
? thisloop
->data
.loop
.end_label
: 0;
2284 loop_stack
= thisloop
;
2285 nesting_stack
= thisloop
;
2287 do_pending_stack_adjust ();
2289 emit_note (NULL_PTR
, NOTE_INSN_LOOP_BEG
);
2290 emit_label (thisloop
->data
.loop
.start_label
);
2295 /* Like expand_start_loop but for a loop where the continuation point
2296 (for expand_continue_loop) will be specified explicitly. */
2299 expand_start_loop_continue_elsewhere (exit_flag
)
2302 struct nesting
*thisloop
= expand_start_loop (exit_flag
);
2303 loop_stack
->data
.loop
.continue_label
= gen_label_rtx ();
2307 /* Begin a null, aka do { } while (0) "loop". But since the contents
2308 of said loop can still contain a break, we must frob the loop nest. */
2311 expand_start_null_loop ()
2313 register struct nesting
*thisloop
= ALLOC_NESTING ();
2315 /* Make an entry on loop_stack for the loop we are entering. */
2317 thisloop
->next
= loop_stack
;
2318 thisloop
->all
= nesting_stack
;
2319 thisloop
->depth
= ++nesting_depth
;
2320 thisloop
->data
.loop
.start_label
= emit_note (NULL
, NOTE_INSN_DELETED
);
2321 thisloop
->data
.loop
.end_label
= gen_label_rtx ();
2322 thisloop
->data
.loop
.alt_end_label
= NULL_RTX
;
2323 thisloop
->data
.loop
.continue_label
= thisloop
->data
.loop
.end_label
;
2324 thisloop
->exit_label
= thisloop
->data
.loop
.end_label
;
2325 loop_stack
= thisloop
;
2326 nesting_stack
= thisloop
;
2331 /* Specify the continuation point for a loop started with
2332 expand_start_loop_continue_elsewhere.
2333 Use this at the point in the code to which a continue statement
2337 expand_loop_continue_here ()
2339 do_pending_stack_adjust ();
2340 emit_note (NULL_PTR
, NOTE_INSN_LOOP_CONT
);
2341 emit_label (loop_stack
->data
.loop
.continue_label
);
2344 /* Finish a loop. Generate a jump back to the top and the loop-exit label.
2345 Pop the block off of loop_stack. */
2350 rtx start_label
= loop_stack
->data
.loop
.start_label
;
2351 rtx insn
= get_last_insn ();
2352 int needs_end_jump
= 1;
2354 /* Mark the continue-point at the top of the loop if none elsewhere. */
2355 if (start_label
== loop_stack
->data
.loop
.continue_label
)
2356 emit_note_before (NOTE_INSN_LOOP_CONT
, start_label
);
2358 do_pending_stack_adjust ();
2360 /* If optimizing, perhaps reorder the loop.
2361 First, try to use a condjump near the end.
2362 expand_exit_loop_if_false ends loops with unconditional jumps,
2365 if (test) goto label;
2367 goto loop_stack->data.loop.end_label
2371 If we find such a pattern, we can end the loop earlier. */
2374 && GET_CODE (insn
) == CODE_LABEL
2375 && LABEL_NAME (insn
) == NULL
2376 && GET_CODE (PREV_INSN (insn
)) == BARRIER
)
2379 rtx jump
= PREV_INSN (PREV_INSN (label
));
2381 if (GET_CODE (jump
) == JUMP_INSN
2382 && GET_CODE (PATTERN (jump
)) == SET
2383 && SET_DEST (PATTERN (jump
)) == pc_rtx
2384 && GET_CODE (SET_SRC (PATTERN (jump
))) == LABEL_REF
2385 && (XEXP (SET_SRC (PATTERN (jump
)), 0)
2386 == loop_stack
->data
.loop
.end_label
))
2390 /* The test might be complex and reference LABEL multiple times,
2391 like the loop in loop_iterations to set vtop. To handle this,
2393 insn
= PREV_INSN (label
);
2394 reorder_insns (label
, label
, start_label
);
2396 for (prev
= PREV_INSN (jump
);; prev
= PREV_INSN (prev
))
2398 /* We ignore line number notes, but if we see any other note,
2399 in particular NOTE_INSN_BLOCK_*, NOTE_INSN_EH_REGION_*,
2400 NOTE_INSN_LOOP_*, we disable this optimization. */
2401 if (GET_CODE (prev
) == NOTE
)
2403 if (NOTE_LINE_NUMBER (prev
) < 0)
2407 if (GET_CODE (prev
) == CODE_LABEL
)
2409 if (GET_CODE (prev
) == JUMP_INSN
)
2411 if (GET_CODE (PATTERN (prev
)) == SET
2412 && SET_DEST (PATTERN (prev
)) == pc_rtx
2413 && GET_CODE (SET_SRC (PATTERN (prev
))) == IF_THEN_ELSE
2414 && (GET_CODE (XEXP (SET_SRC (PATTERN (prev
)), 1))
2416 && XEXP (XEXP (SET_SRC (PATTERN (prev
)), 1), 0) == label
)
2418 XEXP (XEXP (SET_SRC (PATTERN (prev
)), 1), 0)
2420 emit_note_after (NOTE_INSN_LOOP_END
, prev
);
2429 /* If the loop starts with a loop exit, roll that to the end where
2430 it will optimize together with the jump back.
2432 We look for the conditional branch to the exit, except that once
2433 we find such a branch, we don't look past 30 instructions.
2435 In more detail, if the loop presently looks like this (in pseudo-C):
2438 if (test) goto end_label;
2443 transform it to look like:
2449 if (test) goto end_label;
2450 goto newstart_label;
2453 Here, the `test' may actually consist of some reasonably complex
2454 code, terminating in a test. */
2459 ! (GET_CODE (insn
) == JUMP_INSN
2460 && GET_CODE (PATTERN (insn
)) == SET
2461 && SET_DEST (PATTERN (insn
)) == pc_rtx
2462 && GET_CODE (SET_SRC (PATTERN (insn
))) == IF_THEN_ELSE
))
2466 rtx last_test_insn
= NULL_RTX
;
2468 /* Scan insns from the top of the loop looking for a qualified
2469 conditional exit. */
2470 for (insn
= NEXT_INSN (loop_stack
->data
.loop
.start_label
); insn
;
2471 insn
= NEXT_INSN (insn
))
2473 if (GET_CODE (insn
) == NOTE
)
2476 && (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
2477 || NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
))
2478 /* The code that actually moves the exit test will
2479 carefully leave BLOCK notes in their original
2480 location. That means, however, that we can't debug
2481 the exit test itself. So, we refuse to move code
2482 containing BLOCK notes at low optimization levels. */
2485 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EH_REGION_BEG
)
2487 else if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EH_REGION_END
)
2491 /* We've come to the end of an EH region, but
2492 never saw the beginning of that region. That
2493 means that an EH region begins before the top
2494 of the loop, and ends in the middle of it. The
2495 existence of such a situation violates a basic
2496 assumption in this code, since that would imply
2497 that even when EH_REGIONS is zero, we might
2498 move code out of an exception region. */
2502 /* We must not walk into a nested loop. */
2503 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_LOOP_BEG
)
2506 /* We already know this INSN is a NOTE, so there's no
2507 point in looking at it to see if it's a JUMP. */
2511 if (GET_CODE (insn
) == JUMP_INSN
|| GET_CODE (insn
) == INSN
)
2514 if (last_test_insn
&& num_insns
> 30)
2518 /* We don't want to move a partial EH region. Consider:
2532 This isn't legal C++, but here's what it's supposed to
2533 mean: if cond() is true, stop looping. Otherwise,
2534 call bar, and keep looping. In addition, if cond
2535 throws an exception, catch it and keep looping. Such
2536 constructs are certainy legal in LISP.
2538 We should not move the `if (cond()) 0' test since then
2539 the EH-region for the try-block would be broken up.
2540 (In this case we would the EH_BEG note for the `try'
2541 and `if cond()' but not the call to bar() or the
2544 So we don't look for tests within an EH region. */
2547 if (GET_CODE (insn
) == JUMP_INSN
2548 && GET_CODE (PATTERN (insn
)) == SET
2549 && SET_DEST (PATTERN (insn
)) == pc_rtx
)
2551 /* This is indeed a jump. */
2552 rtx dest1
= NULL_RTX
;
2553 rtx dest2
= NULL_RTX
;
2554 rtx potential_last_test
;
2555 if (GET_CODE (SET_SRC (PATTERN (insn
))) == IF_THEN_ELSE
)
2557 /* A conditional jump. */
2558 dest1
= XEXP (SET_SRC (PATTERN (insn
)), 1);
2559 dest2
= XEXP (SET_SRC (PATTERN (insn
)), 2);
2560 potential_last_test
= insn
;
2564 /* An unconditional jump. */
2565 dest1
= SET_SRC (PATTERN (insn
));
2566 /* Include the BARRIER after the JUMP. */
2567 potential_last_test
= NEXT_INSN (insn
);
2571 if (dest1
&& GET_CODE (dest1
) == LABEL_REF
2572 && ((XEXP (dest1
, 0)
2573 == loop_stack
->data
.loop
.alt_end_label
)
2575 == loop_stack
->data
.loop
.end_label
)))
2577 last_test_insn
= potential_last_test
;
2581 /* If this was a conditional jump, there may be
2582 another label at which we should look. */
2589 if (last_test_insn
!= 0 && last_test_insn
!= get_last_insn ())
2591 /* We found one. Move everything from there up
2592 to the end of the loop, and add a jump into the loop
2593 to jump to there. */
2594 register rtx newstart_label
= gen_label_rtx ();
2595 register rtx start_move
= start_label
;
2598 /* If the start label is preceded by a NOTE_INSN_LOOP_CONT note,
2599 then we want to move this note also. */
2600 if (GET_CODE (PREV_INSN (start_move
)) == NOTE
2601 && (NOTE_LINE_NUMBER (PREV_INSN (start_move
))
2602 == NOTE_INSN_LOOP_CONT
))
2603 start_move
= PREV_INSN (start_move
);
2605 emit_label_after (newstart_label
, PREV_INSN (start_move
));
2607 /* Actually move the insns. Start at the beginning, and
2608 keep copying insns until we've copied the
2610 for (insn
= start_move
; insn
; insn
= next_insn
)
2612 /* Figure out which insn comes after this one. We have
2613 to do this before we move INSN. */
2614 if (insn
== last_test_insn
)
2615 /* We've moved all the insns. */
2616 next_insn
= NULL_RTX
;
2618 next_insn
= NEXT_INSN (insn
);
2620 if (GET_CODE (insn
) == NOTE
2621 && (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
2622 || NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
))
2623 /* We don't want to move NOTE_INSN_BLOCK_BEGs or
2624 NOTE_INSN_BLOCK_ENDs because the correct generation
2625 of debugging information depends on these appearing
2626 in the same order in the RTL and in the tree
2627 structure, where they are represented as BLOCKs.
2628 So, we don't move block notes. Of course, moving
2629 the code inside the block is likely to make it
2630 impossible to debug the instructions in the exit
2631 test, but such is the price of optimization. */
2634 /* Move the INSN. */
2635 reorder_insns (insn
, insn
, get_last_insn ());
2638 emit_jump_insn_after (gen_jump (start_label
),
2639 PREV_INSN (newstart_label
));
2640 emit_barrier_after (PREV_INSN (newstart_label
));
2641 start_label
= newstart_label
;
2647 emit_jump (start_label
);
2648 emit_note (NULL_PTR
, NOTE_INSN_LOOP_END
);
2650 emit_label (loop_stack
->data
.loop
.end_label
);
2652 POPSTACK (loop_stack
);
2657 /* Finish a null loop, aka do { } while (0). */
2660 expand_end_null_loop ()
2662 do_pending_stack_adjust ();
2663 emit_label (loop_stack
->data
.loop
.end_label
);
2665 POPSTACK (loop_stack
);
2670 /* Generate a jump to the current loop's continue-point.
2671 This is usually the top of the loop, but may be specified
2672 explicitly elsewhere. If not currently inside a loop,
2673 return 0 and do nothing; caller will print an error message. */
2676 expand_continue_loop (whichloop
)
2677 struct nesting
*whichloop
;
2681 whichloop
= loop_stack
;
2684 expand_goto_internal (NULL_TREE
, whichloop
->data
.loop
.continue_label
,
2689 /* Generate a jump to exit the current loop. If not currently inside a loop,
2690 return 0 and do nothing; caller will print an error message. */
2693 expand_exit_loop (whichloop
)
2694 struct nesting
*whichloop
;
2698 whichloop
= loop_stack
;
2701 expand_goto_internal (NULL_TREE
, whichloop
->data
.loop
.end_label
, NULL_RTX
);
2705 /* Generate a conditional jump to exit the current loop if COND
2706 evaluates to zero. If not currently inside a loop,
2707 return 0 and do nothing; caller will print an error message. */
2710 expand_exit_loop_if_false (whichloop
, cond
)
2711 struct nesting
*whichloop
;
2714 rtx label
= gen_label_rtx ();
2719 whichloop
= loop_stack
;
2722 /* In order to handle fixups, we actually create a conditional jump
2723 around a unconditional branch to exit the loop. If fixups are
2724 necessary, they go before the unconditional branch. */
2726 do_jump (cond
, NULL_RTX
, label
);
2727 last_insn
= get_last_insn ();
2728 if (GET_CODE (last_insn
) == CODE_LABEL
)
2729 whichloop
->data
.loop
.alt_end_label
= last_insn
;
2730 expand_goto_internal (NULL_TREE
, whichloop
->data
.loop
.end_label
,
2737 /* Return nonzero if the loop nest is empty. Else return zero. */
2740 stmt_loop_nest_empty ()
2742 /* cfun->stmt can be NULL if we are building a call to get the
2743 EH context for a setjmp/longjmp EH target and the current
2744 function was a deferred inline function. */
2745 return (cfun
->stmt
== NULL
|| loop_stack
== NULL
);
2748 /* Return non-zero if we should preserve sub-expressions as separate
2749 pseudos. We never do so if we aren't optimizing. We always do so
2750 if -fexpensive-optimizations.
2752 Otherwise, we only do so if we are in the "early" part of a loop. I.e.,
2753 the loop may still be a small one. */
2756 preserve_subexpressions_p ()
2760 if (flag_expensive_optimizations
)
2763 if (optimize
== 0 || cfun
== 0 || cfun
->stmt
== 0 || loop_stack
== 0)
2766 insn
= get_last_insn_anywhere ();
2769 && (INSN_UID (insn
) - INSN_UID (loop_stack
->data
.loop
.start_label
)
2770 < n_non_fixed_regs
* 3));
2774 /* Generate a jump to exit the current loop, conditional, binding contour
2775 or case statement. Not all such constructs are visible to this function,
2776 only those started with EXIT_FLAG nonzero. Individual languages use
2777 the EXIT_FLAG parameter to control which kinds of constructs you can
2780 If not currently inside anything that can be exited,
2781 return 0 and do nothing; caller will print an error message. */
2784 expand_exit_something ()
2788 for (n
= nesting_stack
; n
; n
= n
->all
)
2789 if (n
->exit_label
!= 0)
2791 expand_goto_internal (NULL_TREE
, n
->exit_label
, NULL_RTX
);
2798 /* Generate RTL to return from the current function, with no value.
2799 (That is, we do not do anything about returning any value.) */
2802 expand_null_return ()
2804 struct nesting
*block
= block_stack
;
2805 rtx last_insn
= get_last_insn ();
2807 /* If this function was declared to return a value, but we
2808 didn't, clobber the return registers so that they are not
2809 propogated live to the rest of the function. */
2810 clobber_return_register ();
2812 /* Does any pending block have cleanups? */
2813 while (block
&& block
->data
.block
.cleanups
== 0)
2814 block
= block
->next
;
2816 /* If yes, use a goto to return, since that runs cleanups. */
2818 expand_null_return_1 (last_insn
, block
!= 0);
2821 /* Generate RTL to return from the current function, with value VAL. */
2824 expand_value_return (val
)
2827 struct nesting
*block
= block_stack
;
2828 rtx last_insn
= get_last_insn ();
2829 rtx return_reg
= DECL_RTL (DECL_RESULT (current_function_decl
));
2831 /* Copy the value to the return location
2832 unless it's already there. */
2834 if (return_reg
!= val
)
2836 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
2837 #ifdef PROMOTE_FUNCTION_RETURN
2838 int unsignedp
= TREE_UNSIGNED (type
);
2839 enum machine_mode old_mode
2840 = DECL_MODE (DECL_RESULT (current_function_decl
));
2841 enum machine_mode mode
2842 = promote_mode (type
, old_mode
, &unsignedp
, 1);
2844 if (mode
!= old_mode
)
2845 val
= convert_modes (mode
, old_mode
, val
, unsignedp
);
2847 if (GET_CODE (return_reg
) == PARALLEL
)
2848 emit_group_load (return_reg
, val
, int_size_in_bytes (type
),
2851 emit_move_insn (return_reg
, val
);
2854 /* Does any pending block have cleanups? */
2856 while (block
&& block
->data
.block
.cleanups
== 0)
2857 block
= block
->next
;
2859 /* If yes, use a goto to return, since that runs cleanups.
2860 Use LAST_INSN to put cleanups *before* the move insn emitted above. */
2862 expand_null_return_1 (last_insn
, block
!= 0);
2865 /* Output a return with no value. If LAST_INSN is nonzero,
2866 pretend that the return takes place after LAST_INSN.
2867 If USE_GOTO is nonzero then don't use a return instruction;
2868 go to the return label instead. This causes any cleanups
2869 of pending blocks to be executed normally. */
2872 expand_null_return_1 (last_insn
, use_goto
)
2876 rtx end_label
= cleanup_label
? cleanup_label
: return_label
;
2878 clear_pending_stack_adjust ();
2879 do_pending_stack_adjust ();
2882 /* PCC-struct return always uses an epilogue. */
2883 if (current_function_returns_pcc_struct
|| use_goto
)
2886 end_label
= return_label
= gen_label_rtx ();
2887 expand_goto_internal (NULL_TREE
, end_label
, last_insn
);
2891 /* Otherwise output a simple return-insn if one is available,
2892 unless it won't do the job. */
2894 if (HAVE_return
&& use_goto
== 0 && cleanup_label
== 0)
2896 emit_jump_insn (gen_return ());
2902 /* Otherwise jump to the epilogue. */
2903 expand_goto_internal (NULL_TREE
, end_label
, last_insn
);
2906 /* Generate RTL to evaluate the expression RETVAL and return it
2907 from the current function. */
2910 expand_return (retval
)
2913 /* If there are any cleanups to be performed, then they will
2914 be inserted following LAST_INSN. It is desirable
2915 that the last_insn, for such purposes, should be the
2916 last insn before computing the return value. Otherwise, cleanups
2917 which call functions can clobber the return value. */
2918 /* ??? rms: I think that is erroneous, because in C++ it would
2919 run destructors on variables that might be used in the subsequent
2920 computation of the return value. */
2923 register rtx val
= 0;
2926 /* If function wants no value, give it none. */
2927 if (TREE_CODE (TREE_TYPE (TREE_TYPE (current_function_decl
))) == VOID_TYPE
)
2929 expand_expr (retval
, NULL_RTX
, VOIDmode
, 0);
2931 expand_null_return ();
2935 if (retval
== error_mark_node
)
2937 /* Treat this like a return of no value from a function that
2939 expand_null_return ();
2942 else if (TREE_CODE (retval
) == RESULT_DECL
)
2943 retval_rhs
= retval
;
2944 else if ((TREE_CODE (retval
) == MODIFY_EXPR
|| TREE_CODE (retval
) == INIT_EXPR
)
2945 && TREE_CODE (TREE_OPERAND (retval
, 0)) == RESULT_DECL
)
2946 retval_rhs
= TREE_OPERAND (retval
, 1);
2947 else if (VOID_TYPE_P (TREE_TYPE (retval
)))
2948 /* Recognize tail-recursive call to void function. */
2949 retval_rhs
= retval
;
2951 retval_rhs
= NULL_TREE
;
2953 last_insn
= get_last_insn ();
2955 /* Distribute return down conditional expr if either of the sides
2956 may involve tail recursion (see test below). This enhances the number
2957 of tail recursions we see. Don't do this always since it can produce
2958 sub-optimal code in some cases and we distribute assignments into
2959 conditional expressions when it would help. */
2961 if (optimize
&& retval_rhs
!= 0
2962 && frame_offset
== 0
2963 && TREE_CODE (retval_rhs
) == COND_EXPR
2964 && (TREE_CODE (TREE_OPERAND (retval_rhs
, 1)) == CALL_EXPR
2965 || TREE_CODE (TREE_OPERAND (retval_rhs
, 2)) == CALL_EXPR
))
2967 rtx label
= gen_label_rtx ();
2970 do_jump (TREE_OPERAND (retval_rhs
, 0), label
, NULL_RTX
);
2971 start_cleanup_deferral ();
2972 expr
= build (MODIFY_EXPR
, TREE_TYPE (TREE_TYPE (current_function_decl
)),
2973 DECL_RESULT (current_function_decl
),
2974 TREE_OPERAND (retval_rhs
, 1));
2975 TREE_SIDE_EFFECTS (expr
) = 1;
2976 expand_return (expr
);
2979 expr
= build (MODIFY_EXPR
, TREE_TYPE (TREE_TYPE (current_function_decl
)),
2980 DECL_RESULT (current_function_decl
),
2981 TREE_OPERAND (retval_rhs
, 2));
2982 TREE_SIDE_EFFECTS (expr
) = 1;
2983 expand_return (expr
);
2984 end_cleanup_deferral ();
2988 result_rtl
= DECL_RTL (DECL_RESULT (current_function_decl
));
2990 /* If the result is an aggregate that is being returned in one (or more)
2991 registers, load the registers here. The compiler currently can't handle
2992 copying a BLKmode value into registers. We could put this code in a
2993 more general area (for use by everyone instead of just function
2994 call/return), but until this feature is generally usable it is kept here
2995 (and in expand_call). The value must go into a pseudo in case there
2996 are cleanups that will clobber the real return register. */
2999 && TYPE_MODE (TREE_TYPE (retval_rhs
)) == BLKmode
3000 && GET_CODE (result_rtl
) == REG
)
3003 unsigned HOST_WIDE_INT bitpos
, xbitpos
;
3004 unsigned HOST_WIDE_INT big_endian_correction
= 0;
3005 unsigned HOST_WIDE_INT bytes
3006 = int_size_in_bytes (TREE_TYPE (retval_rhs
));
3007 int n_regs
= (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
3008 unsigned int bitsize
3009 = MIN (TYPE_ALIGN (TREE_TYPE (retval_rhs
)), BITS_PER_WORD
);
3010 rtx
*result_pseudos
= (rtx
*) alloca (sizeof (rtx
) * n_regs
);
3011 rtx result_reg
, src
= NULL_RTX
, dst
= NULL_RTX
;
3012 rtx result_val
= expand_expr (retval_rhs
, NULL_RTX
, VOIDmode
, 0);
3013 enum machine_mode tmpmode
, result_reg_mode
;
3017 expand_null_return ();
3021 /* Structures whose size is not a multiple of a word are aligned
3022 to the least significant byte (to the right). On a BYTES_BIG_ENDIAN
3023 machine, this means we must skip the empty high order bytes when
3024 calculating the bit offset. */
3025 if (BYTES_BIG_ENDIAN
&& bytes
% UNITS_PER_WORD
)
3026 big_endian_correction
= (BITS_PER_WORD
- ((bytes
% UNITS_PER_WORD
)
3029 /* Copy the structure BITSIZE bits at a time. */
3030 for (bitpos
= 0, xbitpos
= big_endian_correction
;
3031 bitpos
< bytes
* BITS_PER_UNIT
;
3032 bitpos
+= bitsize
, xbitpos
+= bitsize
)
3034 /* We need a new destination pseudo each time xbitpos is
3035 on a word boundary and when xbitpos == big_endian_correction
3036 (the first time through). */
3037 if (xbitpos
% BITS_PER_WORD
== 0
3038 || xbitpos
== big_endian_correction
)
3040 /* Generate an appropriate register. */
3041 dst
= gen_reg_rtx (word_mode
);
3042 result_pseudos
[xbitpos
/ BITS_PER_WORD
] = dst
;
3044 /* Clobber the destination before we move anything into it. */
3045 emit_insn (gen_rtx_CLOBBER (VOIDmode
, dst
));
3048 /* We need a new source operand each time bitpos is on a word
3050 if (bitpos
% BITS_PER_WORD
== 0)
3051 src
= operand_subword_force (result_val
,
3052 bitpos
/ BITS_PER_WORD
,
3055 /* Use bitpos for the source extraction (left justified) and
3056 xbitpos for the destination store (right justified). */
3057 store_bit_field (dst
, bitsize
, xbitpos
% BITS_PER_WORD
, word_mode
,
3058 extract_bit_field (src
, bitsize
,
3059 bitpos
% BITS_PER_WORD
, 1,
3060 NULL_RTX
, word_mode
, word_mode
,
3061 bitsize
, BITS_PER_WORD
),
3062 bitsize
, BITS_PER_WORD
);
3065 /* Find the smallest integer mode large enough to hold the
3066 entire structure and use that mode instead of BLKmode
3067 on the USE insn for the return register. */
3068 for (tmpmode
= GET_CLASS_NARROWEST_MODE (MODE_INT
);
3069 tmpmode
!= VOIDmode
;
3070 tmpmode
= GET_MODE_WIDER_MODE (tmpmode
))
3071 /* Have we found a large enough mode? */
3072 if (GET_MODE_SIZE (tmpmode
) >= bytes
)
3075 /* No suitable mode found. */
3076 if (tmpmode
== VOIDmode
)
3079 PUT_MODE (result_rtl
, tmpmode
);
3081 if (GET_MODE_SIZE (tmpmode
) < GET_MODE_SIZE (word_mode
))
3082 result_reg_mode
= word_mode
;
3084 result_reg_mode
= tmpmode
;
3085 result_reg
= gen_reg_rtx (result_reg_mode
);
3088 for (i
= 0; i
< n_regs
; i
++)
3089 emit_move_insn (operand_subword (result_reg
, i
, 0, result_reg_mode
),
3092 if (tmpmode
!= result_reg_mode
)
3093 result_reg
= gen_lowpart (tmpmode
, result_reg
);
3095 expand_value_return (result_reg
);
3097 else if (retval_rhs
!= 0
3098 && !VOID_TYPE_P (TREE_TYPE (retval_rhs
))
3099 && (GET_CODE (result_rtl
) == REG
3100 || (GET_CODE (result_rtl
) == PARALLEL
)))
3102 /* Calculate the return value into a temporary (usually a pseudo
3104 tree ot
= TREE_TYPE (DECL_RESULT (current_function_decl
));
3105 tree nt
= build_qualified_type (ot
, TYPE_QUALS (ot
) | TYPE_QUAL_CONST
);
3107 val
= assign_temp (nt
, 0, 0, 1);
3108 val
= expand_expr (retval_rhs
, val
, GET_MODE (val
), 0);
3109 val
= force_not_mem (val
);
3111 /* Return the calculated value, doing cleanups first. */
3112 expand_value_return (val
);
3116 /* No cleanups or no hard reg used;
3117 calculate value into hard return reg. */
3118 expand_expr (retval
, const0_rtx
, VOIDmode
, 0);
3120 expand_value_return (result_rtl
);
3124 /* Return 1 if the end of the generated RTX is not a barrier.
3125 This means code already compiled can drop through. */
3128 drop_through_at_end_p ()
3130 rtx insn
= get_last_insn ();
3131 while (insn
&& GET_CODE (insn
) == NOTE
)
3132 insn
= PREV_INSN (insn
);
3133 return insn
&& GET_CODE (insn
) != BARRIER
;
3136 /* Attempt to optimize a potential tail recursion call into a goto.
3137 ARGUMENTS are the arguments to a CALL_EXPR; LAST_INSN indicates
3138 where to place the jump to the tail recursion label.
3140 Return TRUE if the call was optimized into a goto. */
3143 optimize_tail_recursion (arguments
, last_insn
)
3147 /* Finish checking validity, and if valid emit code to set the
3148 argument variables for the new call. */
3149 if (tail_recursion_args (arguments
, DECL_ARGUMENTS (current_function_decl
)))
3151 if (tail_recursion_label
== 0)
3153 tail_recursion_label
= gen_label_rtx ();
3154 emit_label_after (tail_recursion_label
,
3155 tail_recursion_reentry
);
3158 expand_goto_internal (NULL_TREE
, tail_recursion_label
, last_insn
);
3165 /* Emit code to alter this function's formal parms for a tail-recursive call.
3166 ACTUALS is a list of actual parameter expressions (chain of TREE_LISTs).
3167 FORMALS is the chain of decls of formals.
3168 Return 1 if this can be done;
3169 otherwise return 0 and do not emit any code. */
3172 tail_recursion_args (actuals
, formals
)
3173 tree actuals
, formals
;
3175 register tree a
= actuals
, f
= formals
;
3177 register rtx
*argvec
;
3179 /* Check that number and types of actuals are compatible
3180 with the formals. This is not always true in valid C code.
3181 Also check that no formal needs to be addressable
3182 and that all formals are scalars. */
3184 /* Also count the args. */
3186 for (a
= actuals
, f
= formals
, i
= 0; a
&& f
; a
= TREE_CHAIN (a
), f
= TREE_CHAIN (f
), i
++)
3188 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_VALUE (a
)))
3189 != TYPE_MAIN_VARIANT (TREE_TYPE (f
)))
3191 if (GET_CODE (DECL_RTL (f
)) != REG
|| DECL_MODE (f
) == BLKmode
)
3194 if (a
!= 0 || f
!= 0)
3197 /* Compute all the actuals. */
3199 argvec
= (rtx
*) alloca (i
* sizeof (rtx
));
3201 for (a
= actuals
, i
= 0; a
; a
= TREE_CHAIN (a
), i
++)
3202 argvec
[i
] = expand_expr (TREE_VALUE (a
), NULL_RTX
, VOIDmode
, 0);
3204 /* Find which actual values refer to current values of previous formals.
3205 Copy each of them now, before any formal is changed. */
3207 for (a
= actuals
, i
= 0; a
; a
= TREE_CHAIN (a
), i
++)
3211 for (f
= formals
, j
= 0; j
< i
; f
= TREE_CHAIN (f
), j
++)
3212 if (reg_mentioned_p (DECL_RTL (f
), argvec
[i
]))
3218 argvec
[i
] = copy_to_reg (argvec
[i
]);
3221 /* Store the values of the actuals into the formals. */
3223 for (f
= formals
, a
= actuals
, i
= 0; f
;
3224 f
= TREE_CHAIN (f
), a
= TREE_CHAIN (a
), i
++)
3226 if (GET_MODE (DECL_RTL (f
)) == GET_MODE (argvec
[i
]))
3227 emit_move_insn (DECL_RTL (f
), argvec
[i
]);
3229 convert_move (DECL_RTL (f
), argvec
[i
],
3230 TREE_UNSIGNED (TREE_TYPE (TREE_VALUE (a
))));
3237 /* Generate the RTL code for entering a binding contour.
3238 The variables are declared one by one, by calls to `expand_decl'.
3240 FLAGS is a bitwise or of the following flags:
3242 1 - Nonzero if this construct should be visible to
3245 2 - Nonzero if this contour does not require a
3246 NOTE_INSN_BLOCK_BEG note. Virtually all calls from
3247 language-independent code should set this flag because they
3248 will not create corresponding BLOCK nodes. (There should be
3249 a one-to-one correspondence between NOTE_INSN_BLOCK_BEG notes
3250 and BLOCKs.) If this flag is set, MARK_ENDS should be zero
3251 when expand_end_bindings is called.
3253 If we are creating a NOTE_INSN_BLOCK_BEG note, a BLOCK may
3254 optionally be supplied. If so, it becomes the NOTE_BLOCK for the
3258 expand_start_bindings_and_block (flags
, block
)
3262 struct nesting
*thisblock
= ALLOC_NESTING ();
3264 int exit_flag
= ((flags
& 1) != 0);
3265 int block_flag
= ((flags
& 2) == 0);
3267 /* If a BLOCK is supplied, then the caller should be requesting a
3268 NOTE_INSN_BLOCK_BEG note. */
3269 if (!block_flag
&& block
)
3272 /* Create a note to mark the beginning of the block. */
3275 note
= emit_note (NULL_PTR
, NOTE_INSN_BLOCK_BEG
);
3276 NOTE_BLOCK (note
) = block
;
3279 note
= emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
3281 /* Make an entry on block_stack for the block we are entering. */
3283 thisblock
->next
= block_stack
;
3284 thisblock
->all
= nesting_stack
;
3285 thisblock
->depth
= ++nesting_depth
;
3286 thisblock
->data
.block
.stack_level
= 0;
3287 thisblock
->data
.block
.cleanups
= 0;
3288 thisblock
->data
.block
.n_function_calls
= 0;
3289 thisblock
->data
.block
.exception_region
= 0;
3290 thisblock
->data
.block
.block_target_temp_slot_level
= target_temp_slot_level
;
3292 thisblock
->data
.block
.conditional_code
= 0;
3293 thisblock
->data
.block
.last_unconditional_cleanup
= note
;
3294 /* When we insert instructions after the last unconditional cleanup,
3295 we don't adjust last_insn. That means that a later add_insn will
3296 clobber the instructions we've just added. The easiest way to
3297 fix this is to just insert another instruction here, so that the
3298 instructions inserted after the last unconditional cleanup are
3299 never the last instruction. */
3300 emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
3301 thisblock
->data
.block
.cleanup_ptr
= &thisblock
->data
.block
.cleanups
;
3304 && !(block_stack
->data
.block
.cleanups
== NULL_TREE
3305 && block_stack
->data
.block
.outer_cleanups
== NULL_TREE
))
3306 thisblock
->data
.block
.outer_cleanups
3307 = tree_cons (NULL_TREE
, block_stack
->data
.block
.cleanups
,
3308 block_stack
->data
.block
.outer_cleanups
);
3310 thisblock
->data
.block
.outer_cleanups
= 0;
3311 thisblock
->data
.block
.label_chain
= 0;
3312 thisblock
->data
.block
.innermost_stack_block
= stack_block_stack
;
3313 thisblock
->data
.block
.first_insn
= note
;
3314 thisblock
->data
.block
.block_start_count
= ++current_block_start_count
;
3315 thisblock
->exit_label
= exit_flag
? gen_label_rtx () : 0;
3316 block_stack
= thisblock
;
3317 nesting_stack
= thisblock
;
3319 /* Make a new level for allocating stack slots. */
3323 /* Specify the scope of temporaries created by TARGET_EXPRs. Similar
3324 to CLEANUP_POINT_EXPR, but handles cases when a series of calls to
3325 expand_expr are made. After we end the region, we know that all
3326 space for all temporaries that were created by TARGET_EXPRs will be
3327 destroyed and their space freed for reuse. */
3330 expand_start_target_temps ()
3332 /* This is so that even if the result is preserved, the space
3333 allocated will be freed, as we know that it is no longer in use. */
3336 /* Start a new binding layer that will keep track of all cleanup
3337 actions to be performed. */
3338 expand_start_bindings (2);
3340 target_temp_slot_level
= temp_slot_level
;
3344 expand_end_target_temps ()
3346 expand_end_bindings (NULL_TREE
, 0, 0);
3348 /* This is so that even if the result is preserved, the space
3349 allocated will be freed, as we know that it is no longer in use. */
3353 /* Given a pointer to a BLOCK node return non-zero if (and only if) the node
3354 in question represents the outermost pair of curly braces (i.e. the "body
3355 block") of a function or method.
3357 For any BLOCK node representing a "body block" of a function or method, the
3358 BLOCK_SUPERCONTEXT of the node will point to another BLOCK node which
3359 represents the outermost (function) scope for the function or method (i.e.
3360 the one which includes the formal parameters). The BLOCK_SUPERCONTEXT of
3361 *that* node in turn will point to the relevant FUNCTION_DECL node. */
3364 is_body_block (stmt
)
3367 if (TREE_CODE (stmt
) == BLOCK
)
3369 tree parent
= BLOCK_SUPERCONTEXT (stmt
);
3371 if (parent
&& TREE_CODE (parent
) == BLOCK
)
3373 tree grandparent
= BLOCK_SUPERCONTEXT (parent
);
3375 if (grandparent
&& TREE_CODE (grandparent
) == FUNCTION_DECL
)
3383 /* Mark top block of block_stack as an implicit binding for an
3384 exception region. This is used to prevent infinite recursion when
3385 ending a binding with expand_end_bindings. It is only ever called
3386 by expand_eh_region_start, as that it the only way to create a
3387 block stack for a exception region. */
3390 mark_block_as_eh_region ()
3392 block_stack
->data
.block
.exception_region
= 1;
3393 if (block_stack
->next
3394 && block_stack
->next
->data
.block
.conditional_code
)
3396 block_stack
->data
.block
.conditional_code
3397 = block_stack
->next
->data
.block
.conditional_code
;
3398 block_stack
->data
.block
.last_unconditional_cleanup
3399 = block_stack
->next
->data
.block
.last_unconditional_cleanup
;
3400 block_stack
->data
.block
.cleanup_ptr
3401 = block_stack
->next
->data
.block
.cleanup_ptr
;
3405 /* True if we are currently emitting insns in an area of output code
3406 that is controlled by a conditional expression. This is used by
3407 the cleanup handling code to generate conditional cleanup actions. */
3410 conditional_context ()
3412 return block_stack
&& block_stack
->data
.block
.conditional_code
;
3415 /* Mark top block of block_stack as not for an implicit binding for an
3416 exception region. This is only ever done by expand_eh_region_end
3417 to let expand_end_bindings know that it is being called explicitly
3418 to end the binding layer for just the binding layer associated with
3419 the exception region, otherwise expand_end_bindings would try and
3420 end all implicit binding layers for exceptions regions, and then
3421 one normal binding layer. */
3424 mark_block_as_not_eh_region ()
3426 block_stack
->data
.block
.exception_region
= 0;
3429 /* True if the top block of block_stack was marked as for an exception
3430 region by mark_block_as_eh_region. */
3435 return cfun
&& block_stack
&& block_stack
->data
.block
.exception_region
;
3438 /* Emit a handler label for a nonlocal goto handler.
3439 Also emit code to store the handler label in SLOT before BEFORE_INSN. */
3442 expand_nl_handler_label (slot
, before_insn
)
3443 rtx slot
, before_insn
;
3446 rtx handler_label
= gen_label_rtx ();
3448 /* Don't let jump_optimize delete the handler. */
3449 LABEL_PRESERVE_P (handler_label
) = 1;
3452 emit_move_insn (slot
, gen_rtx_LABEL_REF (Pmode
, handler_label
));
3453 insns
= get_insns ();
3455 emit_insns_before (insns
, before_insn
);
3457 emit_label (handler_label
);
3459 return handler_label
;
3462 /* Emit code to restore vital registers at the beginning of a nonlocal goto
3465 expand_nl_goto_receiver ()
3467 #ifdef HAVE_nonlocal_goto
3468 if (! HAVE_nonlocal_goto
)
3470 /* First adjust our frame pointer to its actual value. It was
3471 previously set to the start of the virtual area corresponding to
3472 the stacked variables when we branched here and now needs to be
3473 adjusted to the actual hardware fp value.
3475 Assignments are to virtual registers are converted by
3476 instantiate_virtual_regs into the corresponding assignment
3477 to the underlying register (fp in this case) that makes
3478 the original assignment true.
3479 So the following insn will actually be
3480 decrementing fp by STARTING_FRAME_OFFSET. */
3481 emit_move_insn (virtual_stack_vars_rtx
, hard_frame_pointer_rtx
);
3483 #if ARG_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
3484 if (fixed_regs
[ARG_POINTER_REGNUM
])
3486 #ifdef ELIMINABLE_REGS
3487 /* If the argument pointer can be eliminated in favor of the
3488 frame pointer, we don't need to restore it. We assume here
3489 that if such an elimination is present, it can always be used.
3490 This is the case on all known machines; if we don't make this
3491 assumption, we do unnecessary saving on many machines. */
3492 static struct elims
{int from
, to
;} elim_regs
[] = ELIMINABLE_REGS
;
3495 for (i
= 0; i
< ARRAY_SIZE (elim_regs
); i
++)
3496 if (elim_regs
[i
].from
== ARG_POINTER_REGNUM
3497 && elim_regs
[i
].to
== HARD_FRAME_POINTER_REGNUM
)
3500 if (i
== ARRAY_SIZE (elim_regs
))
3503 /* Now restore our arg pointer from the address at which it
3504 was saved in our stack frame.
3505 If there hasn't be space allocated for it yet, make
3507 if (arg_pointer_save_area
== 0)
3508 arg_pointer_save_area
3509 = assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
3510 emit_move_insn (virtual_incoming_args_rtx
,
3511 /* We need a pseudo here, or else
3512 instantiate_virtual_regs_1 complains. */
3513 copy_to_reg (arg_pointer_save_area
));
3518 #ifdef HAVE_nonlocal_goto_receiver
3519 if (HAVE_nonlocal_goto_receiver
)
3520 emit_insn (gen_nonlocal_goto_receiver ());
3524 /* Make handlers for nonlocal gotos taking place in the function calls in
3528 expand_nl_goto_receivers (thisblock
)
3529 struct nesting
*thisblock
;
3532 rtx afterward
= gen_label_rtx ();
3537 /* Record the handler address in the stack slot for that purpose,
3538 during this block, saving and restoring the outer value. */
3539 if (thisblock
->next
!= 0)
3540 for (slot
= nonlocal_goto_handler_slots
; slot
; slot
= XEXP (slot
, 1))
3542 rtx save_receiver
= gen_reg_rtx (Pmode
);
3543 emit_move_insn (XEXP (slot
, 0), save_receiver
);
3546 emit_move_insn (save_receiver
, XEXP (slot
, 0));
3547 insns
= get_insns ();
3549 emit_insns_before (insns
, thisblock
->data
.block
.first_insn
);
3552 /* Jump around the handlers; they run only when specially invoked. */
3553 emit_jump (afterward
);
3555 /* Make a separate handler for each label. */
3556 link
= nonlocal_labels
;
3557 slot
= nonlocal_goto_handler_slots
;
3558 label_list
= NULL_RTX
;
3559 for (; link
; link
= TREE_CHAIN (link
), slot
= XEXP (slot
, 1))
3560 /* Skip any labels we shouldn't be able to jump to from here,
3561 we generate one special handler for all of them below which just calls
3563 if (! DECL_TOO_LATE (TREE_VALUE (link
)))
3566 lab
= expand_nl_handler_label (XEXP (slot
, 0),
3567 thisblock
->data
.block
.first_insn
);
3568 label_list
= gen_rtx_EXPR_LIST (VOIDmode
, lab
, label_list
);
3570 expand_nl_goto_receiver ();
3572 /* Jump to the "real" nonlocal label. */
3573 expand_goto (TREE_VALUE (link
));
3576 /* A second pass over all nonlocal labels; this time we handle those
3577 we should not be able to jump to at this point. */
3578 link
= nonlocal_labels
;
3579 slot
= nonlocal_goto_handler_slots
;
3581 for (; link
; link
= TREE_CHAIN (link
), slot
= XEXP (slot
, 1))
3582 if (DECL_TOO_LATE (TREE_VALUE (link
)))
3585 lab
= expand_nl_handler_label (XEXP (slot
, 0),
3586 thisblock
->data
.block
.first_insn
);
3587 label_list
= gen_rtx_EXPR_LIST (VOIDmode
, lab
, label_list
);
3593 expand_nl_goto_receiver ();
3594 emit_library_call (gen_rtx_SYMBOL_REF (Pmode
, "abort"), 0,
3599 nonlocal_goto_handler_labels
= label_list
;
3600 emit_label (afterward
);
3603 /* Warn about any unused VARS (which may contain nodes other than
3604 VAR_DECLs, but such nodes are ignored). The nodes are connected
3605 via the TREE_CHAIN field. */
3608 warn_about_unused_variables (vars
)
3613 if (warn_unused_variable
)
3614 for (decl
= vars
; decl
; decl
= TREE_CHAIN (decl
))
3615 if (TREE_CODE (decl
) == VAR_DECL
3616 && ! TREE_USED (decl
)
3617 && ! DECL_IN_SYSTEM_HEADER (decl
)
3618 && DECL_NAME (decl
) && ! DECL_ARTIFICIAL (decl
))
3619 warning_with_decl (decl
, "unused variable `%s'");
3622 /* Generate RTL code to terminate a binding contour.
3624 VARS is the chain of VAR_DECL nodes for the variables bound in this
3625 contour. There may actually be other nodes in this chain, but any
3626 nodes other than VAR_DECLS are ignored.
3628 MARK_ENDS is nonzero if we should put a note at the beginning
3629 and end of this binding contour.
3631 DONT_JUMP_IN is nonzero if it is not valid to jump into this contour.
3632 (That is true automatically if the contour has a saved stack level.) */
3635 expand_end_bindings (vars
, mark_ends
, dont_jump_in
)
3640 register struct nesting
*thisblock
;
3642 while (block_stack
->data
.block
.exception_region
)
3644 /* Because we don't need or want a new temporary level and
3645 because we didn't create one in expand_eh_region_start,
3646 create a fake one now to avoid removing one in
3647 expand_end_bindings. */
3650 block_stack
->data
.block
.exception_region
= 0;
3652 expand_end_bindings (NULL_TREE
, 0, 0);
3655 /* Since expand_eh_region_start does an expand_start_bindings, we
3656 have to first end all the bindings that were created by
3657 expand_eh_region_start. */
3659 thisblock
= block_stack
;
3661 /* If any of the variables in this scope were not used, warn the
3663 warn_about_unused_variables (vars
);
3665 if (thisblock
->exit_label
)
3667 do_pending_stack_adjust ();
3668 emit_label (thisblock
->exit_label
);
3671 /* If necessary, make handlers for nonlocal gotos taking
3672 place in the function calls in this block. */
3673 if (function_call_count
!= thisblock
->data
.block
.n_function_calls
3675 /* Make handler for outermost block
3676 if there were any nonlocal gotos to this function. */
3677 && (thisblock
->next
== 0 ? current_function_has_nonlocal_label
3678 /* Make handler for inner block if it has something
3679 special to do when you jump out of it. */
3680 : (thisblock
->data
.block
.cleanups
!= 0
3681 || thisblock
->data
.block
.stack_level
!= 0)))
3682 expand_nl_goto_receivers (thisblock
);
3684 /* Don't allow jumping into a block that has a stack level.
3685 Cleanups are allowed, though. */
3687 || thisblock
->data
.block
.stack_level
!= 0)
3689 struct label_chain
*chain
;
3691 /* Any labels in this block are no longer valid to go to.
3692 Mark them to cause an error message. */
3693 for (chain
= thisblock
->data
.block
.label_chain
; chain
; chain
= chain
->next
)
3695 DECL_TOO_LATE (chain
->label
) = 1;
3696 /* If any goto without a fixup came to this label,
3697 that must be an error, because gotos without fixups
3698 come from outside all saved stack-levels. */
3699 if (TREE_ADDRESSABLE (chain
->label
))
3700 error_with_decl (chain
->label
,
3701 "label `%s' used before containing binding contour");
3705 /* Restore stack level in effect before the block
3706 (only if variable-size objects allocated). */
3707 /* Perform any cleanups associated with the block. */
3709 if (thisblock
->data
.block
.stack_level
!= 0
3710 || thisblock
->data
.block
.cleanups
!= 0)
3715 /* Don't let cleanups affect ({...}) constructs. */
3716 int old_expr_stmts_for_value
= expr_stmts_for_value
;
3717 rtx old_last_expr_value
= last_expr_value
;
3718 tree old_last_expr_type
= last_expr_type
;
3719 expr_stmts_for_value
= 0;
3721 /* Only clean up here if this point can actually be reached. */
3722 insn
= get_last_insn ();
3723 if (GET_CODE (insn
) == NOTE
)
3724 insn
= prev_nonnote_insn (insn
);
3725 reachable
= (! insn
|| GET_CODE (insn
) != BARRIER
);
3727 /* Do the cleanups. */
3728 expand_cleanups (thisblock
->data
.block
.cleanups
, NULL_TREE
, 0, reachable
);
3730 do_pending_stack_adjust ();
3732 expr_stmts_for_value
= old_expr_stmts_for_value
;
3733 last_expr_value
= old_last_expr_value
;
3734 last_expr_type
= old_last_expr_type
;
3736 /* Restore the stack level. */
3738 if (reachable
&& thisblock
->data
.block
.stack_level
!= 0)
3740 emit_stack_restore (thisblock
->next
? SAVE_BLOCK
: SAVE_FUNCTION
,
3741 thisblock
->data
.block
.stack_level
, NULL_RTX
);
3742 if (nonlocal_goto_handler_slots
!= 0)
3743 emit_stack_save (SAVE_NONLOCAL
, &nonlocal_goto_stack_level
,
3747 /* Any gotos out of this block must also do these things.
3748 Also report any gotos with fixups that came to labels in this
3750 fixup_gotos (thisblock
,
3751 thisblock
->data
.block
.stack_level
,
3752 thisblock
->data
.block
.cleanups
,
3753 thisblock
->data
.block
.first_insn
,
3757 /* Mark the beginning and end of the scope if requested.
3758 We do this now, after running cleanups on the variables
3759 just going out of scope, so they are in scope for their cleanups. */
3763 rtx note
= emit_note (NULL_PTR
, NOTE_INSN_BLOCK_END
);
3764 NOTE_BLOCK (note
) = NOTE_BLOCK (thisblock
->data
.block
.first_insn
);
3767 /* Get rid of the beginning-mark if we don't make an end-mark. */
3768 NOTE_LINE_NUMBER (thisblock
->data
.block
.first_insn
) = NOTE_INSN_DELETED
;
3770 /* Restore the temporary level of TARGET_EXPRs. */
3771 target_temp_slot_level
= thisblock
->data
.block
.block_target_temp_slot_level
;
3773 /* Restore block_stack level for containing block. */
3775 stack_block_stack
= thisblock
->data
.block
.innermost_stack_block
;
3776 POPSTACK (block_stack
);
3778 /* Pop the stack slot nesting and free any slots at this level. */
3782 /* Generate code to save the stack pointer at the start of the current block
3783 and set up to restore it on exit. */
3786 save_stack_pointer ()
3788 struct nesting
*thisblock
= block_stack
;
3790 if (thisblock
->data
.block
.stack_level
== 0)
3792 emit_stack_save (thisblock
->next
? SAVE_BLOCK
: SAVE_FUNCTION
,
3793 &thisblock
->data
.block
.stack_level
,
3794 thisblock
->data
.block
.first_insn
);
3795 stack_block_stack
= thisblock
;
3799 /* Generate RTL for the automatic variable declaration DECL.
3800 (Other kinds of declarations are simply ignored if seen here.) */
3806 struct nesting
*thisblock
;
3809 type
= TREE_TYPE (decl
);
3811 /* Only automatic variables need any expansion done.
3812 Static and external variables, and external functions,
3813 will be handled by `assemble_variable' (called from finish_decl).
3814 TYPE_DECL and CONST_DECL require nothing.
3815 PARM_DECLs are handled in `assign_parms'. */
3817 if (TREE_CODE (decl
) != VAR_DECL
)
3819 if (TREE_STATIC (decl
) || DECL_EXTERNAL (decl
))
3822 thisblock
= block_stack
;
3824 /* Create the RTL representation for the variable. */
3826 if (type
== error_mark_node
)
3827 SET_DECL_RTL (decl
, gen_rtx_MEM (BLKmode
, const0_rtx
));
3829 else if (DECL_SIZE (decl
) == 0)
3830 /* Variable with incomplete type. */
3832 if (DECL_INITIAL (decl
) == 0)
3833 /* Error message was already done; now avoid a crash. */
3834 SET_DECL_RTL (decl
, gen_rtx_MEM (BLKmode
, const0_rtx
));
3836 /* An initializer is going to decide the size of this array.
3837 Until we know the size, represent its address with a reg. */
3838 SET_DECL_RTL (decl
, gen_rtx_MEM (BLKmode
, gen_reg_rtx (Pmode
)));
3840 set_mem_attributes (DECL_RTL (decl
), decl
, 1);
3842 else if (DECL_MODE (decl
) != BLKmode
3843 /* If -ffloat-store, don't put explicit float vars
3845 && !(flag_float_store
3846 && TREE_CODE (type
) == REAL_TYPE
)
3847 && ! TREE_THIS_VOLATILE (decl
)
3848 && (DECL_REGISTER (decl
) || optimize
)
3849 /* if -fcheck-memory-usage, check all variables. */
3850 && ! current_function_check_memory_usage
)
3852 /* Automatic variable that can go in a register. */
3853 int unsignedp
= TREE_UNSIGNED (type
);
3854 enum machine_mode reg_mode
3855 = promote_mode (type
, DECL_MODE (decl
), &unsignedp
, 0);
3857 SET_DECL_RTL (decl
, gen_reg_rtx (reg_mode
));
3858 mark_user_reg (DECL_RTL (decl
));
3860 if (POINTER_TYPE_P (type
))
3861 mark_reg_pointer (DECL_RTL (decl
),
3862 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl
))));
3864 maybe_set_unchanging (DECL_RTL (decl
), decl
);
3866 /* If something wants our address, try to use ADDRESSOF. */
3867 if (TREE_ADDRESSABLE (decl
))
3868 put_var_into_stack (decl
);
3871 else if (TREE_CODE (DECL_SIZE_UNIT (decl
)) == INTEGER_CST
3872 && ! (flag_stack_check
&& ! STACK_CHECK_BUILTIN
3873 && 0 < compare_tree_int (DECL_SIZE_UNIT (decl
),
3874 STACK_CHECK_MAX_VAR_SIZE
)))
3876 /* Variable of fixed size that goes on the stack. */
3880 /* If we previously made RTL for this decl, it must be an array
3881 whose size was determined by the initializer.
3882 The old address was a register; set that register now
3883 to the proper address. */
3884 if (DECL_RTL_SET_P (decl
))
3886 if (GET_CODE (DECL_RTL (decl
)) != MEM
3887 || GET_CODE (XEXP (DECL_RTL (decl
), 0)) != REG
)
3889 oldaddr
= XEXP (DECL_RTL (decl
), 0);
3893 assign_temp (TREE_TYPE (decl
), 1, 1, 1));
3895 /* Set alignment we actually gave this decl. */
3896 DECL_ALIGN (decl
) = (DECL_MODE (decl
) == BLKmode
? BIGGEST_ALIGNMENT
3897 : GET_MODE_BITSIZE (DECL_MODE (decl
)));
3898 DECL_USER_ALIGN (decl
) = 0;
3902 addr
= force_operand (XEXP (DECL_RTL (decl
), 0), oldaddr
);
3903 if (addr
!= oldaddr
)
3904 emit_move_insn (oldaddr
, addr
);
3908 /* Dynamic-size object: must push space on the stack. */
3912 /* Record the stack pointer on entry to block, if have
3913 not already done so. */
3914 do_pending_stack_adjust ();
3915 save_stack_pointer ();
3917 /* In function-at-a-time mode, variable_size doesn't expand this,
3919 if (TREE_CODE (type
) == ARRAY_TYPE
&& TYPE_DOMAIN (type
))
3920 expand_expr (TYPE_MAX_VALUE (TYPE_DOMAIN (type
)),
3921 const0_rtx
, VOIDmode
, 0);
3923 /* Compute the variable's size, in bytes. */
3924 size
= expand_expr (DECL_SIZE_UNIT (decl
), NULL_RTX
, VOIDmode
, 0);
3927 /* Allocate space on the stack for the variable. Note that
3928 DECL_ALIGN says how the variable is to be aligned and we
3929 cannot use it to conclude anything about the alignment of
3931 address
= allocate_dynamic_stack_space (size
, NULL_RTX
,
3932 TYPE_ALIGN (TREE_TYPE (decl
)));
3934 /* Reference the variable indirect through that rtx. */
3935 SET_DECL_RTL (decl
, gen_rtx_MEM (DECL_MODE (decl
), address
));
3937 set_mem_attributes (DECL_RTL (decl
), decl
, 1);
3939 /* Indicate the alignment we actually gave this variable. */
3940 #ifdef STACK_BOUNDARY
3941 DECL_ALIGN (decl
) = STACK_BOUNDARY
;
3943 DECL_ALIGN (decl
) = BIGGEST_ALIGNMENT
;
3945 DECL_USER_ALIGN (decl
) = 0;
3949 /* Emit code to perform the initialization of a declaration DECL. */
3952 expand_decl_init (decl
)
3955 int was_used
= TREE_USED (decl
);
3957 /* If this is a CONST_DECL, we don't have to generate any code, but
3958 if DECL_INITIAL is a constant, call expand_expr to force TREE_CST_RTL
3959 to be set while in the obstack containing the constant. If we don't
3960 do this, we can lose if we have functions nested three deep and the middle
3961 function makes a CONST_DECL whose DECL_INITIAL is a STRING_CST while
3962 the innermost function is the first to expand that STRING_CST. */
3963 if (TREE_CODE (decl
) == CONST_DECL
)
3965 if (DECL_INITIAL (decl
) && TREE_CONSTANT (DECL_INITIAL (decl
)))
3966 expand_expr (DECL_INITIAL (decl
), NULL_RTX
, VOIDmode
,
3967 EXPAND_INITIALIZER
);
3971 if (TREE_STATIC (decl
))
3974 /* Compute and store the initial value now. */
3976 if (DECL_INITIAL (decl
) == error_mark_node
)
3978 enum tree_code code
= TREE_CODE (TREE_TYPE (decl
));
3980 if (code
== INTEGER_TYPE
|| code
== REAL_TYPE
|| code
== ENUMERAL_TYPE
3981 || code
== POINTER_TYPE
|| code
== REFERENCE_TYPE
)
3982 expand_assignment (decl
, convert (TREE_TYPE (decl
), integer_zero_node
),
3986 else if (DECL_INITIAL (decl
) && TREE_CODE (DECL_INITIAL (decl
)) != TREE_LIST
)
3988 emit_line_note (DECL_SOURCE_FILE (decl
), DECL_SOURCE_LINE (decl
));
3989 expand_assignment (decl
, DECL_INITIAL (decl
), 0, 0);
3993 /* Don't let the initialization count as "using" the variable. */
3994 TREE_USED (decl
) = was_used
;
3996 /* Free any temporaries we made while initializing the decl. */
3997 preserve_temp_slots (NULL_RTX
);
4001 /* CLEANUP is an expression to be executed at exit from this binding contour;
4002 for example, in C++, it might call the destructor for this variable.
4004 We wrap CLEANUP in an UNSAVE_EXPR node, so that we can expand the
4005 CLEANUP multiple times, and have the correct semantics. This
4006 happens in exception handling, for gotos, returns, breaks that
4007 leave the current scope.
4009 If CLEANUP is nonzero and DECL is zero, we record a cleanup
4010 that is not associated with any particular variable. */
4013 expand_decl_cleanup (decl
, cleanup
)
4016 struct nesting
*thisblock
;
4018 /* Error if we are not in any block. */
4019 if (cfun
== 0 || block_stack
== 0)
4022 thisblock
= block_stack
;
4024 /* Record the cleanup if there is one. */
4030 tree
*cleanups
= &thisblock
->data
.block
.cleanups
;
4031 int cond_context
= conditional_context ();
4035 rtx flag
= gen_reg_rtx (word_mode
);
4040 emit_move_insn (flag
, const0_rtx
);
4041 set_flag_0
= get_insns ();
4044 thisblock
->data
.block
.last_unconditional_cleanup
4045 = emit_insns_after (set_flag_0
,
4046 thisblock
->data
.block
.last_unconditional_cleanup
);
4048 emit_move_insn (flag
, const1_rtx
);
4050 cond
= build_decl (VAR_DECL
, NULL_TREE
, type_for_mode (word_mode
, 1));
4051 SET_DECL_RTL (cond
, flag
);
4053 /* Conditionalize the cleanup. */
4054 cleanup
= build (COND_EXPR
, void_type_node
,
4055 truthvalue_conversion (cond
),
4056 cleanup
, integer_zero_node
);
4057 cleanup
= fold (cleanup
);
4059 cleanups
= thisblock
->data
.block
.cleanup_ptr
;
4062 cleanup
= unsave_expr (cleanup
);
4064 t
= *cleanups
= tree_cons (decl
, cleanup
, *cleanups
);
4067 /* If this block has a cleanup, it belongs in stack_block_stack. */
4068 stack_block_stack
= thisblock
;
4075 if (! using_eh_for_cleanups_p
)
4076 TREE_ADDRESSABLE (t
) = 1;
4078 expand_eh_region_start ();
4080 /* If that started a new EH region, we're in a new block. */
4081 thisblock
= block_stack
;
4088 thisblock
->data
.block
.last_unconditional_cleanup
4089 = emit_insns_after (seq
,
4090 thisblock
->data
.block
.last_unconditional_cleanup
);
4094 thisblock
->data
.block
.last_unconditional_cleanup
4096 /* When we insert instructions after the last unconditional cleanup,
4097 we don't adjust last_insn. That means that a later add_insn will
4098 clobber the instructions we've just added. The easiest way to
4099 fix this is to just insert another instruction here, so that the
4100 instructions inserted after the last unconditional cleanup are
4101 never the last instruction. */
4102 emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
4103 thisblock
->data
.block
.cleanup_ptr
= &thisblock
->data
.block
.cleanups
;
4109 /* DECL is an anonymous union. CLEANUP is a cleanup for DECL.
4110 DECL_ELTS is the list of elements that belong to DECL's type.
4111 In each, the TREE_VALUE is a VAR_DECL, and the TREE_PURPOSE a cleanup. */
4114 expand_anon_union_decl (decl
, cleanup
, decl_elts
)
4115 tree decl
, cleanup
, decl_elts
;
4117 struct nesting
*thisblock
= cfun
== 0 ? 0 : block_stack
;
4121 /* If any of the elements are addressable, so is the entire union. */
4122 for (t
= decl_elts
; t
; t
= TREE_CHAIN (t
))
4123 if (TREE_ADDRESSABLE (TREE_VALUE (t
)))
4125 TREE_ADDRESSABLE (decl
) = 1;
4130 expand_decl_cleanup (decl
, cleanup
);
4131 x
= DECL_RTL (decl
);
4133 /* Go through the elements, assigning RTL to each. */
4134 for (t
= decl_elts
; t
; t
= TREE_CHAIN (t
))
4136 tree decl_elt
= TREE_VALUE (t
);
4137 tree cleanup_elt
= TREE_PURPOSE (t
);
4138 enum machine_mode mode
= TYPE_MODE (TREE_TYPE (decl_elt
));
4140 /* Propagate the union's alignment to the elements. */
4141 DECL_ALIGN (decl_elt
) = DECL_ALIGN (decl
);
4142 DECL_USER_ALIGN (decl_elt
) = DECL_USER_ALIGN (decl
);
4144 /* If the element has BLKmode and the union doesn't, the union is
4145 aligned such that the element doesn't need to have BLKmode, so
4146 change the element's mode to the appropriate one for its size. */
4147 if (mode
== BLKmode
&& DECL_MODE (decl
) != BLKmode
)
4148 DECL_MODE (decl_elt
) = mode
4149 = mode_for_size_tree (DECL_SIZE (decl_elt
), MODE_INT
, 1);
4151 /* (SUBREG (MEM ...)) at RTL generation time is invalid, so we
4152 instead create a new MEM rtx with the proper mode. */
4153 if (GET_CODE (x
) == MEM
)
4155 if (mode
== GET_MODE (x
))
4156 SET_DECL_RTL (decl_elt
, x
);
4159 SET_DECL_RTL (decl_elt
,
4160 gen_rtx_MEM (mode
, copy_rtx (XEXP (x
, 0))));
4161 MEM_COPY_ATTRIBUTES (DECL_RTL (decl_elt
), x
);
4164 else if (GET_CODE (x
) == REG
)
4166 if (mode
== GET_MODE (x
))
4167 SET_DECL_RTL (decl_elt
, x
);
4169 SET_DECL_RTL (decl_elt
, gen_rtx_SUBREG (mode
, x
, 0));
4174 /* Record the cleanup if there is one. */
4177 thisblock
->data
.block
.cleanups
4178 = tree_cons (decl_elt
, cleanup_elt
,
4179 thisblock
->data
.block
.cleanups
);
4183 /* Expand a list of cleanups LIST.
4184 Elements may be expressions or may be nested lists.
4186 If DONT_DO is nonnull, then any list-element
4187 whose TREE_PURPOSE matches DONT_DO is omitted.
4188 This is sometimes used to avoid a cleanup associated with
4189 a value that is being returned out of the scope.
4191 If IN_FIXUP is non-zero, we are generating this cleanup for a fixup
4192 goto and handle protection regions specially in that case.
4194 If REACHABLE, we emit code, otherwise just inform the exception handling
4195 code about this finalization. */
4198 expand_cleanups (list
, dont_do
, in_fixup
, reachable
)
4205 for (tail
= list
; tail
; tail
= TREE_CHAIN (tail
))
4206 if (dont_do
== 0 || TREE_PURPOSE (tail
) != dont_do
)
4208 if (TREE_CODE (TREE_VALUE (tail
)) == TREE_LIST
)
4209 expand_cleanups (TREE_VALUE (tail
), dont_do
, in_fixup
, reachable
);
4212 if (! in_fixup
&& using_eh_for_cleanups_p
)
4213 expand_eh_region_end_cleanup (TREE_VALUE (tail
));
4217 /* Cleanups may be run multiple times. For example,
4218 when exiting a binding contour, we expand the
4219 cleanups associated with that contour. When a goto
4220 within that binding contour has a target outside that
4221 contour, it will expand all cleanups from its scope to
4222 the target. Though the cleanups are expanded multiple
4223 times, the control paths are non-overlapping so the
4224 cleanups will not be executed twice. */
4226 /* We may need to protect from outer cleanups. */
4227 if (in_fixup
&& using_eh_for_cleanups_p
)
4229 expand_eh_region_start ();
4231 expand_expr (TREE_VALUE (tail
), const0_rtx
, VOIDmode
, 0);
4233 expand_eh_region_end_fixup (TREE_VALUE (tail
));
4236 expand_expr (TREE_VALUE (tail
), const0_rtx
, VOIDmode
, 0);
4244 /* Mark when the context we are emitting RTL for as a conditional
4245 context, so that any cleanup actions we register with
4246 expand_decl_init will be properly conditionalized when those
4247 cleanup actions are later performed. Must be called before any
4248 expression (tree) is expanded that is within a conditional context. */
4251 start_cleanup_deferral ()
4253 /* block_stack can be NULL if we are inside the parameter list. It is
4254 OK to do nothing, because cleanups aren't possible here. */
4256 ++block_stack
->data
.block
.conditional_code
;
4259 /* Mark the end of a conditional region of code. Because cleanup
4260 deferrals may be nested, we may still be in a conditional region
4261 after we end the currently deferred cleanups, only after we end all
4262 deferred cleanups, are we back in unconditional code. */
4265 end_cleanup_deferral ()
4267 /* block_stack can be NULL if we are inside the parameter list. It is
4268 OK to do nothing, because cleanups aren't possible here. */
4270 --block_stack
->data
.block
.conditional_code
;
4273 /* Move all cleanups from the current block_stack
4274 to the containing block_stack, where they are assumed to
4275 have been created. If anything can cause a temporary to
4276 be created, but not expanded for more than one level of
4277 block_stacks, then this code will have to change. */
4282 struct nesting
*block
= block_stack
;
4283 struct nesting
*outer
= block
->next
;
4285 outer
->data
.block
.cleanups
4286 = chainon (block
->data
.block
.cleanups
,
4287 outer
->data
.block
.cleanups
);
4288 block
->data
.block
.cleanups
= 0;
4292 last_cleanup_this_contour ()
4294 if (block_stack
== 0)
4297 return block_stack
->data
.block
.cleanups
;
4300 /* Return 1 if there are any pending cleanups at this point.
4301 If THIS_CONTOUR is nonzero, check the current contour as well.
4302 Otherwise, look only at the contours that enclose this one. */
4305 any_pending_cleanups (this_contour
)
4308 struct nesting
*block
;
4310 if (cfun
== NULL
|| cfun
->stmt
== NULL
|| block_stack
== 0)
4313 if (this_contour
&& block_stack
->data
.block
.cleanups
!= NULL
)
4315 if (block_stack
->data
.block
.cleanups
== 0
4316 && block_stack
->data
.block
.outer_cleanups
== 0)
4319 for (block
= block_stack
->next
; block
; block
= block
->next
)
4320 if (block
->data
.block
.cleanups
!= 0)
4326 /* Enter a case (Pascal) or switch (C) statement.
4327 Push a block onto case_stack and nesting_stack
4328 to accumulate the case-labels that are seen
4329 and to record the labels generated for the statement.
4331 EXIT_FLAG is nonzero if `exit_something' should exit this case stmt.
4332 Otherwise, this construct is transparent for `exit_something'.
4334 EXPR is the index-expression to be dispatched on.
4335 TYPE is its nominal type. We could simply convert EXPR to this type,
4336 but instead we take short cuts. */
4339 expand_start_case (exit_flag
, expr
, type
, printname
)
4343 const char *printname
;
4345 register struct nesting
*thiscase
= ALLOC_NESTING ();
4347 /* Make an entry on case_stack for the case we are entering. */
4349 thiscase
->next
= case_stack
;
4350 thiscase
->all
= nesting_stack
;
4351 thiscase
->depth
= ++nesting_depth
;
4352 thiscase
->exit_label
= exit_flag
? gen_label_rtx () : 0;
4353 thiscase
->data
.case_stmt
.case_list
= 0;
4354 thiscase
->data
.case_stmt
.index_expr
= expr
;
4355 thiscase
->data
.case_stmt
.nominal_type
= type
;
4356 thiscase
->data
.case_stmt
.default_label
= 0;
4357 thiscase
->data
.case_stmt
.printname
= printname
;
4358 thiscase
->data
.case_stmt
.line_number_status
= force_line_numbers ();
4359 case_stack
= thiscase
;
4360 nesting_stack
= thiscase
;
4362 do_pending_stack_adjust ();
4364 /* Make sure case_stmt.start points to something that won't
4365 need any transformation before expand_end_case. */
4366 if (GET_CODE (get_last_insn ()) != NOTE
)
4367 emit_note (NULL_PTR
, NOTE_INSN_DELETED
);
4369 thiscase
->data
.case_stmt
.start
= get_last_insn ();
4371 start_cleanup_deferral ();
4374 /* Start a "dummy case statement" within which case labels are invalid
4375 and are not connected to any larger real case statement.
4376 This can be used if you don't want to let a case statement jump
4377 into the middle of certain kinds of constructs. */
4380 expand_start_case_dummy ()
4382 register struct nesting
*thiscase
= ALLOC_NESTING ();
4384 /* Make an entry on case_stack for the dummy. */
4386 thiscase
->next
= case_stack
;
4387 thiscase
->all
= nesting_stack
;
4388 thiscase
->depth
= ++nesting_depth
;
4389 thiscase
->exit_label
= 0;
4390 thiscase
->data
.case_stmt
.case_list
= 0;
4391 thiscase
->data
.case_stmt
.start
= 0;
4392 thiscase
->data
.case_stmt
.nominal_type
= 0;
4393 thiscase
->data
.case_stmt
.default_label
= 0;
4394 case_stack
= thiscase
;
4395 nesting_stack
= thiscase
;
4396 start_cleanup_deferral ();
4399 /* End a dummy case statement. */
4402 expand_end_case_dummy ()
4404 end_cleanup_deferral ();
4405 POPSTACK (case_stack
);
4408 /* Return the data type of the index-expression
4409 of the innermost case statement, or null if none. */
4412 case_index_expr_type ()
4415 return TREE_TYPE (case_stack
->data
.case_stmt
.index_expr
);
4422 /* If this is the first label, warn if any insns have been emitted. */
4423 if (case_stack
->data
.case_stmt
.line_number_status
>= 0)
4427 restore_line_number_status
4428 (case_stack
->data
.case_stmt
.line_number_status
);
4429 case_stack
->data
.case_stmt
.line_number_status
= -1;
4431 for (insn
= case_stack
->data
.case_stmt
.start
;
4433 insn
= NEXT_INSN (insn
))
4435 if (GET_CODE (insn
) == CODE_LABEL
)
4437 if (GET_CODE (insn
) != NOTE
4438 && (GET_CODE (insn
) != INSN
|| GET_CODE (PATTERN (insn
)) != USE
))
4441 insn
= PREV_INSN (insn
);
4442 while (insn
&& (GET_CODE (insn
) != NOTE
|| NOTE_LINE_NUMBER (insn
) < 0));
4444 /* If insn is zero, then there must have been a syntax error. */
4446 warning_with_file_and_line (NOTE_SOURCE_FILE (insn
),
4447 NOTE_LINE_NUMBER (insn
),
4448 "unreachable code at beginning of %s",
4449 case_stack
->data
.case_stmt
.printname
);
4456 /* Accumulate one case or default label inside a case or switch statement.
4457 VALUE is the value of the case (a null pointer, for a default label).
4458 The function CONVERTER, when applied to arguments T and V,
4459 converts the value V to the type T.
4461 If not currently inside a case or switch statement, return 1 and do
4462 nothing. The caller will print a language-specific error message.
4463 If VALUE is a duplicate or overlaps, return 2 and do nothing
4464 except store the (first) duplicate node in *DUPLICATE.
4465 If VALUE is out of range, return 3 and do nothing.
4466 If we are jumping into the scope of a cleanup or var-sized array, return 5.
4467 Return 0 on success.
4469 Extended to handle range statements. */
4472 pushcase (value
, converter
, label
, duplicate
)
4473 register tree value
;
4474 tree (*converter
) PARAMS ((tree
, tree
));
4475 register tree label
;
4481 /* Fail if not inside a real case statement. */
4482 if (! (case_stack
&& case_stack
->data
.case_stmt
.start
))
4485 if (stack_block_stack
4486 && stack_block_stack
->depth
> case_stack
->depth
)
4489 index_type
= TREE_TYPE (case_stack
->data
.case_stmt
.index_expr
);
4490 nominal_type
= case_stack
->data
.case_stmt
.nominal_type
;
4492 /* If the index is erroneous, avoid more problems: pretend to succeed. */
4493 if (index_type
== error_mark_node
)
4496 /* Convert VALUE to the type in which the comparisons are nominally done. */
4498 value
= (*converter
) (nominal_type
, value
);
4502 /* Fail if this value is out of range for the actual type of the index
4503 (which may be narrower than NOMINAL_TYPE). */
4505 && (TREE_CONSTANT_OVERFLOW (value
)
4506 || ! int_fits_type_p (value
, index_type
)))
4509 return add_case_node (value
, value
, label
, duplicate
);
4512 /* Like pushcase but this case applies to all values between VALUE1 and
4513 VALUE2 (inclusive). If VALUE1 is NULL, the range starts at the lowest
4514 value of the index type and ends at VALUE2. If VALUE2 is NULL, the range
4515 starts at VALUE1 and ends at the highest value of the index type.
4516 If both are NULL, this case applies to all values.
4518 The return value is the same as that of pushcase but there is one
4519 additional error code: 4 means the specified range was empty. */
4522 pushcase_range (value1
, value2
, converter
, label
, duplicate
)
4523 register tree value1
, value2
;
4524 tree (*converter
) PARAMS ((tree
, tree
));
4525 register tree label
;
4531 /* Fail if not inside a real case statement. */
4532 if (! (case_stack
&& case_stack
->data
.case_stmt
.start
))
4535 if (stack_block_stack
4536 && stack_block_stack
->depth
> case_stack
->depth
)
4539 index_type
= TREE_TYPE (case_stack
->data
.case_stmt
.index_expr
);
4540 nominal_type
= case_stack
->data
.case_stmt
.nominal_type
;
4542 /* If the index is erroneous, avoid more problems: pretend to succeed. */
4543 if (index_type
== error_mark_node
)
4548 /* Convert VALUEs to type in which the comparisons are nominally done
4549 and replace any unspecified value with the corresponding bound. */
4551 value1
= TYPE_MIN_VALUE (index_type
);
4553 value2
= TYPE_MAX_VALUE (index_type
);
4555 /* Fail if the range is empty. Do this before any conversion since
4556 we want to allow out-of-range empty ranges. */
4557 if (value2
!= 0 && tree_int_cst_lt (value2
, value1
))
4560 /* If the max was unbounded, use the max of the nominal_type we are
4561 converting to. Do this after the < check above to suppress false
4564 value2
= TYPE_MAX_VALUE (nominal_type
);
4566 value1
= (*converter
) (nominal_type
, value1
);
4567 value2
= (*converter
) (nominal_type
, value2
);
4569 /* Fail if these values are out of range. */
4570 if (TREE_CONSTANT_OVERFLOW (value1
)
4571 || ! int_fits_type_p (value1
, index_type
))
4574 if (TREE_CONSTANT_OVERFLOW (value2
)
4575 || ! int_fits_type_p (value2
, index_type
))
4578 return add_case_node (value1
, value2
, label
, duplicate
);
4581 /* Do the actual insertion of a case label for pushcase and pushcase_range
4582 into case_stack->data.case_stmt.case_list. Use an AVL tree to avoid
4583 slowdown for large switch statements. */
4586 add_case_node (low
, high
, label
, duplicate
)
4591 struct case_node
*p
, **q
, *r
;
4593 /* If there's no HIGH value, then this is not a case range; it's
4594 just a simple case label. But that's just a degenerate case
4599 /* Handle default labels specially. */
4602 if (case_stack
->data
.case_stmt
.default_label
!= 0)
4604 *duplicate
= case_stack
->data
.case_stmt
.default_label
;
4607 case_stack
->data
.case_stmt
.default_label
= label
;
4608 expand_label (label
);
4612 q
= &case_stack
->data
.case_stmt
.case_list
;
4619 /* Keep going past elements distinctly greater than HIGH. */
4620 if (tree_int_cst_lt (high
, p
->low
))
4623 /* or distinctly less than LOW. */
4624 else if (tree_int_cst_lt (p
->high
, low
))
4629 /* We have an overlap; this is an error. */
4630 *duplicate
= p
->code_label
;
4635 /* Add this label to the chain, and succeed. */
4637 r
= (struct case_node
*) xmalloc (sizeof (struct case_node
));
4640 /* If the bounds are equal, turn this into the one-value case. */
4641 if (tree_int_cst_equal (low
, high
))
4646 r
->code_label
= label
;
4647 expand_label (label
);
4657 struct case_node
*s
;
4663 if (! (b
= p
->balance
))
4664 /* Growth propagation from left side. */
4671 if ((p
->left
= s
= r
->right
))
4680 if ((r
->parent
= s
))
4688 case_stack
->data
.case_stmt
.case_list
= r
;
4691 /* r->balance == +1 */
4696 struct case_node
*t
= r
->right
;
4698 if ((p
->left
= s
= t
->right
))
4702 if ((r
->right
= s
= t
->left
))
4716 if ((t
->parent
= s
))
4724 case_stack
->data
.case_stmt
.case_list
= t
;
4731 /* p->balance == +1; growth of left side balances the node. */
4741 if (! (b
= p
->balance
))
4742 /* Growth propagation from right side. */
4750 if ((p
->right
= s
= r
->left
))
4758 if ((r
->parent
= s
))
4767 case_stack
->data
.case_stmt
.case_list
= r
;
4771 /* r->balance == -1 */
4775 struct case_node
*t
= r
->left
;
4777 if ((p
->right
= s
= t
->left
))
4782 if ((r
->left
= s
= t
->right
))
4796 if ((t
->parent
= s
))
4805 case_stack
->data
.case_stmt
.case_list
= t
;
4811 /* p->balance == -1; growth of right side balances the node. */
4824 /* Returns the number of possible values of TYPE.
4825 Returns -1 if the number is unknown, variable, or if the number does not
4826 fit in a HOST_WIDE_INT.
4827 Sets *SPARENESS to 2 if TYPE is an ENUMERAL_TYPE whose values
4828 do not increase monotonically (there may be duplicates);
4829 to 1 if the values increase monotonically, but not always by 1;
4830 otherwise sets it to 0. */
4833 all_cases_count (type
, spareness
)
4838 HOST_WIDE_INT count
, minval
, lastval
;
4842 switch (TREE_CODE (type
))
4849 count
= 1 << BITS_PER_UNIT
;
4854 if (TYPE_MAX_VALUE (type
) != 0
4855 && 0 != (t
= fold (build (MINUS_EXPR
, type
, TYPE_MAX_VALUE (type
),
4856 TYPE_MIN_VALUE (type
))))
4857 && 0 != (t
= fold (build (PLUS_EXPR
, type
, t
,
4858 convert (type
, integer_zero_node
))))
4859 && host_integerp (t
, 1))
4860 count
= tree_low_cst (t
, 1);
4866 /* Don't waste time with enumeral types with huge values. */
4867 if (! host_integerp (TYPE_MIN_VALUE (type
), 0)
4868 || TYPE_MAX_VALUE (type
) == 0
4869 || ! host_integerp (TYPE_MAX_VALUE (type
), 0))
4872 lastval
= minval
= tree_low_cst (TYPE_MIN_VALUE (type
), 0);
4875 for (t
= TYPE_VALUES (type
); t
!= NULL_TREE
; t
= TREE_CHAIN (t
))
4877 HOST_WIDE_INT thisval
= tree_low_cst (TREE_VALUE (t
), 0);
4879 if (*spareness
== 2 || thisval
< lastval
)
4881 else if (thisval
!= minval
+ count
)
4891 #define BITARRAY_TEST(ARRAY, INDEX) \
4892 ((ARRAY)[(unsigned) (INDEX) / HOST_BITS_PER_CHAR]\
4893 & (1 << ((unsigned) (INDEX) % HOST_BITS_PER_CHAR)))
4894 #define BITARRAY_SET(ARRAY, INDEX) \
4895 ((ARRAY)[(unsigned) (INDEX) / HOST_BITS_PER_CHAR]\
4896 |= 1 << ((unsigned) (INDEX) % HOST_BITS_PER_CHAR))
4898 /* Set the elements of the bitstring CASES_SEEN (which has length COUNT),
4899 with the case values we have seen, assuming the case expression
4901 SPARSENESS is as determined by all_cases_count.
4903 The time needed is proportional to COUNT, unless
4904 SPARSENESS is 2, in which case quadratic time is needed. */
4907 mark_seen_cases (type
, cases_seen
, count
, sparseness
)
4909 unsigned char *cases_seen
;
4910 HOST_WIDE_INT count
;
4913 tree next_node_to_try
= NULL_TREE
;
4914 HOST_WIDE_INT next_node_offset
= 0;
4916 register struct case_node
*n
, *root
= case_stack
->data
.case_stmt
.case_list
;
4917 tree val
= make_node (INTEGER_CST
);
4919 TREE_TYPE (val
) = type
;
4923 else if (sparseness
== 2)
4926 unsigned HOST_WIDE_INT xlo
;
4928 /* This less efficient loop is only needed to handle
4929 duplicate case values (multiple enum constants
4930 with the same value). */
4931 TREE_TYPE (val
) = TREE_TYPE (root
->low
);
4932 for (t
= TYPE_VALUES (type
), xlo
= 0; t
!= NULL_TREE
;
4933 t
= TREE_CHAIN (t
), xlo
++)
4935 TREE_INT_CST_LOW (val
) = TREE_INT_CST_LOW (TREE_VALUE (t
));
4936 TREE_INT_CST_HIGH (val
) = TREE_INT_CST_HIGH (TREE_VALUE (t
));
4940 /* Keep going past elements distinctly greater than VAL. */
4941 if (tree_int_cst_lt (val
, n
->low
))
4944 /* or distinctly less than VAL. */
4945 else if (tree_int_cst_lt (n
->high
, val
))
4950 /* We have found a matching range. */
4951 BITARRAY_SET (cases_seen
, xlo
);
4961 case_stack
->data
.case_stmt
.case_list
= root
= case_tree2list (root
, 0);
4963 for (n
= root
; n
; n
= n
->right
)
4965 TREE_INT_CST_LOW (val
) = TREE_INT_CST_LOW (n
->low
);
4966 TREE_INT_CST_HIGH (val
) = TREE_INT_CST_HIGH (n
->low
);
4967 while (! tree_int_cst_lt (n
->high
, val
))
4969 /* Calculate (into xlo) the "offset" of the integer (val).
4970 The element with lowest value has offset 0, the next smallest
4971 element has offset 1, etc. */
4973 unsigned HOST_WIDE_INT xlo
;
4977 if (sparseness
&& TYPE_VALUES (type
) != NULL_TREE
)
4979 /* The TYPE_VALUES will be in increasing order, so
4980 starting searching where we last ended. */
4981 t
= next_node_to_try
;
4982 xlo
= next_node_offset
;
4988 t
= TYPE_VALUES (type
);
4991 if (tree_int_cst_equal (val
, TREE_VALUE (t
)))
4993 next_node_to_try
= TREE_CHAIN (t
);
4994 next_node_offset
= xlo
+ 1;
4999 if (t
== next_node_to_try
)
5008 t
= TYPE_MIN_VALUE (type
);
5010 neg_double (TREE_INT_CST_LOW (t
), TREE_INT_CST_HIGH (t
),
5014 add_double (xlo
, xhi
,
5015 TREE_INT_CST_LOW (val
), TREE_INT_CST_HIGH (val
),
5019 if (xhi
== 0 && xlo
< (unsigned HOST_WIDE_INT
) count
)
5020 BITARRAY_SET (cases_seen
, xlo
);
5022 add_double (TREE_INT_CST_LOW (val
), TREE_INT_CST_HIGH (val
),
5024 &TREE_INT_CST_LOW (val
), &TREE_INT_CST_HIGH (val
));
5030 /* Called when the index of a switch statement is an enumerated type
5031 and there is no default label.
5033 Checks that all enumeration literals are covered by the case
5034 expressions of a switch. Also, warn if there are any extra
5035 switch cases that are *not* elements of the enumerated type.
5037 If all enumeration literals were covered by the case expressions,
5038 turn one of the expressions into the default expression since it should
5039 not be possible to fall through such a switch. */
5042 check_for_full_enumeration_handling (type
)
5045 register struct case_node
*n
;
5046 register tree chain
;
5047 #if 0 /* variable used by 'if 0'ed code below. */
5048 register struct case_node
**l
;
5052 /* True iff the selector type is a numbered set mode. */
5055 /* The number of possible selector values. */
5058 /* For each possible selector value. a one iff it has been matched
5059 by a case value alternative. */
5060 unsigned char *cases_seen
;
5062 /* The allocated size of cases_seen, in chars. */
5063 HOST_WIDE_INT bytes_needed
;
5068 size
= all_cases_count (type
, &sparseness
);
5069 bytes_needed
= (size
+ HOST_BITS_PER_CHAR
) / HOST_BITS_PER_CHAR
;
5071 if (size
> 0 && size
< 600000
5072 /* We deliberately use calloc here, not cmalloc, so that we can suppress
5073 this optimization if we don't have enough memory rather than
5074 aborting, as xmalloc would do. */
5076 (unsigned char *) really_call_calloc (bytes_needed
, 1)) != NULL
)
5079 tree v
= TYPE_VALUES (type
);
5081 /* The time complexity of this code is normally O(N), where
5082 N being the number of members in the enumerated type.
5083 However, if type is a ENUMERAL_TYPE whose values do not
5084 increase monotonically, O(N*log(N)) time may be needed. */
5086 mark_seen_cases (type
, cases_seen
, size
, sparseness
);
5088 for (i
= 0; v
!= NULL_TREE
&& i
< size
; i
++, v
= TREE_CHAIN (v
))
5089 if (BITARRAY_TEST (cases_seen
, i
) == 0)
5090 warning ("enumeration value `%s' not handled in switch",
5091 IDENTIFIER_POINTER (TREE_PURPOSE (v
)));
5096 /* Now we go the other way around; we warn if there are case
5097 expressions that don't correspond to enumerators. This can
5098 occur since C and C++ don't enforce type-checking of
5099 assignments to enumeration variables. */
5101 if (case_stack
->data
.case_stmt
.case_list
5102 && case_stack
->data
.case_stmt
.case_list
->left
)
5103 case_stack
->data
.case_stmt
.case_list
5104 = case_tree2list (case_stack
->data
.case_stmt
.case_list
, 0);
5106 for (n
= case_stack
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5108 for (chain
= TYPE_VALUES (type
);
5109 chain
&& !tree_int_cst_equal (n
->low
, TREE_VALUE (chain
));
5110 chain
= TREE_CHAIN (chain
))
5115 if (TYPE_NAME (type
) == 0)
5116 warning ("case value `%ld' not in enumerated type",
5117 (long) TREE_INT_CST_LOW (n
->low
));
5119 warning ("case value `%ld' not in enumerated type `%s'",
5120 (long) TREE_INT_CST_LOW (n
->low
),
5121 IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type
))
5124 : DECL_NAME (TYPE_NAME (type
))));
5126 if (!tree_int_cst_equal (n
->low
, n
->high
))
5128 for (chain
= TYPE_VALUES (type
);
5129 chain
&& !tree_int_cst_equal (n
->high
, TREE_VALUE (chain
));
5130 chain
= TREE_CHAIN (chain
))
5135 if (TYPE_NAME (type
) == 0)
5136 warning ("case value `%ld' not in enumerated type",
5137 (long) TREE_INT_CST_LOW (n
->high
));
5139 warning ("case value `%ld' not in enumerated type `%s'",
5140 (long) TREE_INT_CST_LOW (n
->high
),
5141 IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type
))
5144 : DECL_NAME (TYPE_NAME (type
))));
5150 /* ??? This optimization is disabled because it causes valid programs to
5151 fail. ANSI C does not guarantee that an expression with enum type
5152 will have a value that is the same as one of the enumeration literals. */
5154 /* If all values were found as case labels, make one of them the default
5155 label. Thus, this switch will never fall through. We arbitrarily pick
5156 the last one to make the default since this is likely the most
5157 efficient choice. */
5161 for (l
= &case_stack
->data
.case_stmt
.case_list
;
5166 case_stack
->data
.case_stmt
.default_label
= (*l
)->code_label
;
5172 /* Free CN, and its children. */
5175 free_case_nodes (cn
)
5180 free_case_nodes (cn
->left
);
5181 free_case_nodes (cn
->right
);
5187 /* Terminate a case (Pascal) or switch (C) statement
5188 in which ORIG_INDEX is the expression to be tested.
5189 Generate the code to test it and jump to the right place. */
5192 expand_end_case (orig_index
)
5195 tree minval
= NULL_TREE
, maxval
= NULL_TREE
, range
= NULL_TREE
, orig_minval
;
5196 rtx default_label
= 0;
5197 register struct case_node
*n
;
5205 register struct nesting
*thiscase
= case_stack
;
5206 tree index_expr
, index_type
;
5209 /* Don't crash due to previous errors. */
5210 if (thiscase
== NULL
)
5213 table_label
= gen_label_rtx ();
5214 index_expr
= thiscase
->data
.case_stmt
.index_expr
;
5215 index_type
= TREE_TYPE (index_expr
);
5216 unsignedp
= TREE_UNSIGNED (index_type
);
5218 do_pending_stack_adjust ();
5220 /* This might get an spurious warning in the presence of a syntax error;
5221 it could be fixed by moving the call to check_seenlabel after the
5222 check for error_mark_node, and copying the code of check_seenlabel that
5223 deals with case_stack->data.case_stmt.line_number_status /
5224 restore_line_number_status in front of the call to end_cleanup_deferral;
5225 However, this might miss some useful warnings in the presence of
5226 non-syntax errors. */
5229 /* An ERROR_MARK occurs for various reasons including invalid data type. */
5230 if (index_type
!= error_mark_node
)
5232 /* If switch expression was an enumerated type, check that all
5233 enumeration literals are covered by the cases.
5234 No sense trying this if there's a default case, however. */
5236 if (!thiscase
->data
.case_stmt
.default_label
5237 && TREE_CODE (TREE_TYPE (orig_index
)) == ENUMERAL_TYPE
5238 && TREE_CODE (index_expr
) != INTEGER_CST
)
5239 check_for_full_enumeration_handling (TREE_TYPE (orig_index
));
5241 /* If we don't have a default-label, create one here,
5242 after the body of the switch. */
5243 if (thiscase
->data
.case_stmt
.default_label
== 0)
5245 thiscase
->data
.case_stmt
.default_label
5246 = build_decl (LABEL_DECL
, NULL_TREE
, NULL_TREE
);
5247 expand_label (thiscase
->data
.case_stmt
.default_label
);
5249 default_label
= label_rtx (thiscase
->data
.case_stmt
.default_label
);
5251 before_case
= get_last_insn ();
5253 if (thiscase
->data
.case_stmt
.case_list
5254 && thiscase
->data
.case_stmt
.case_list
->left
)
5255 thiscase
->data
.case_stmt
.case_list
5256 = case_tree2list (thiscase
->data
.case_stmt
.case_list
, 0);
5258 /* Simplify the case-list before we count it. */
5259 group_case_nodes (thiscase
->data
.case_stmt
.case_list
);
5261 /* Get upper and lower bounds of case values.
5262 Also convert all the case values to the index expr's data type. */
5265 for (n
= thiscase
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5267 /* Check low and high label values are integers. */
5268 if (TREE_CODE (n
->low
) != INTEGER_CST
)
5270 if (TREE_CODE (n
->high
) != INTEGER_CST
)
5273 n
->low
= convert (index_type
, n
->low
);
5274 n
->high
= convert (index_type
, n
->high
);
5276 /* Count the elements and track the largest and smallest
5277 of them (treating them as signed even if they are not). */
5285 if (INT_CST_LT (n
->low
, minval
))
5287 if (INT_CST_LT (maxval
, n
->high
))
5290 /* A range counts double, since it requires two compares. */
5291 if (! tree_int_cst_equal (n
->low
, n
->high
))
5295 orig_minval
= minval
;
5297 /* Compute span of values. */
5299 range
= fold (build (MINUS_EXPR
, index_type
, maxval
, minval
));
5301 end_cleanup_deferral ();
5305 expand_expr (index_expr
, const0_rtx
, VOIDmode
, 0);
5307 emit_jump (default_label
);
5310 /* If range of values is much bigger than number of values,
5311 make a sequence of conditional branches instead of a dispatch.
5312 If the switch-index is a constant, do it this way
5313 because we can optimize it. */
5315 #ifndef CASE_VALUES_THRESHOLD
5317 #define CASE_VALUES_THRESHOLD (HAVE_casesi ? 4 : 5)
5319 /* If machine does not have a case insn that compares the
5320 bounds, this means extra overhead for dispatch tables
5321 which raises the threshold for using them. */
5322 #define CASE_VALUES_THRESHOLD 5
5323 #endif /* HAVE_casesi */
5324 #endif /* CASE_VALUES_THRESHOLD */
5326 else if (count
< CASE_VALUES_THRESHOLD
5327 || compare_tree_int (range
, 10 * count
) > 0
5328 /* RANGE may be signed, and really large ranges will show up
5329 as negative numbers. */
5330 || compare_tree_int (range
, 0) < 0
5331 #ifndef ASM_OUTPUT_ADDR_DIFF_ELT
5334 || TREE_CODE (index_expr
) == INTEGER_CST
5335 /* These will reduce to a constant. */
5336 || (TREE_CODE (index_expr
) == CALL_EXPR
5337 && TREE_CODE (TREE_OPERAND (index_expr
, 0)) == ADDR_EXPR
5338 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (index_expr
, 0), 0)) == FUNCTION_DECL
5339 && DECL_BUILT_IN_CLASS (TREE_OPERAND (TREE_OPERAND (index_expr
, 0), 0)) == BUILT_IN_NORMAL
5340 && DECL_FUNCTION_CODE (TREE_OPERAND (TREE_OPERAND (index_expr
, 0), 0)) == BUILT_IN_CLASSIFY_TYPE
)
5341 || (TREE_CODE (index_expr
) == COMPOUND_EXPR
5342 && TREE_CODE (TREE_OPERAND (index_expr
, 1)) == INTEGER_CST
))
5344 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5346 /* If the index is a short or char that we do not have
5347 an insn to handle comparisons directly, convert it to
5348 a full integer now, rather than letting each comparison
5349 generate the conversion. */
5351 if (GET_MODE_CLASS (GET_MODE (index
)) == MODE_INT
5352 && (cmp_optab
->handlers
[(int) GET_MODE (index
)].insn_code
5353 == CODE_FOR_nothing
))
5355 enum machine_mode wider_mode
;
5356 for (wider_mode
= GET_MODE (index
); wider_mode
!= VOIDmode
;
5357 wider_mode
= GET_MODE_WIDER_MODE (wider_mode
))
5358 if (cmp_optab
->handlers
[(int) wider_mode
].insn_code
5359 != CODE_FOR_nothing
)
5361 index
= convert_to_mode (wider_mode
, index
, unsignedp
);
5367 do_pending_stack_adjust ();
5369 index
= protect_from_queue (index
, 0);
5370 if (GET_CODE (index
) == MEM
)
5371 index
= copy_to_reg (index
);
5372 if (GET_CODE (index
) == CONST_INT
5373 || TREE_CODE (index_expr
) == INTEGER_CST
)
5375 /* Make a tree node with the proper constant value
5376 if we don't already have one. */
5377 if (TREE_CODE (index_expr
) != INTEGER_CST
)
5380 = build_int_2 (INTVAL (index
),
5381 unsignedp
|| INTVAL (index
) >= 0 ? 0 : -1);
5382 index_expr
= convert (index_type
, index_expr
);
5385 /* For constant index expressions we need only
5386 issue a unconditional branch to the appropriate
5387 target code. The job of removing any unreachable
5388 code is left to the optimisation phase if the
5389 "-O" option is specified. */
5390 for (n
= thiscase
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5391 if (! tree_int_cst_lt (index_expr
, n
->low
)
5392 && ! tree_int_cst_lt (n
->high
, index_expr
))
5396 emit_jump (label_rtx (n
->code_label
));
5398 emit_jump (default_label
);
5402 /* If the index expression is not constant we generate
5403 a binary decision tree to select the appropriate
5404 target code. This is done as follows:
5406 The list of cases is rearranged into a binary tree,
5407 nearly optimal assuming equal probability for each case.
5409 The tree is transformed into RTL, eliminating
5410 redundant test conditions at the same time.
5412 If program flow could reach the end of the
5413 decision tree an unconditional jump to the
5414 default code is emitted. */
5417 = (TREE_CODE (TREE_TYPE (orig_index
)) != ENUMERAL_TYPE
5418 && estimate_case_costs (thiscase
->data
.case_stmt
.case_list
));
5419 balance_case_nodes (&thiscase
->data
.case_stmt
.case_list
,
5421 emit_case_nodes (index
, thiscase
->data
.case_stmt
.case_list
,
5422 default_label
, index_type
);
5423 emit_jump_if_reachable (default_label
);
5432 enum machine_mode index_mode
= SImode
;
5433 int index_bits
= GET_MODE_BITSIZE (index_mode
);
5435 enum machine_mode op_mode
;
5437 /* Convert the index to SImode. */
5438 if (GET_MODE_BITSIZE (TYPE_MODE (index_type
))
5439 > GET_MODE_BITSIZE (index_mode
))
5441 enum machine_mode omode
= TYPE_MODE (index_type
);
5442 rtx rangertx
= expand_expr (range
, NULL_RTX
, VOIDmode
, 0);
5444 /* We must handle the endpoints in the original mode. */
5445 index_expr
= build (MINUS_EXPR
, index_type
,
5446 index_expr
, minval
);
5447 minval
= integer_zero_node
;
5448 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5449 emit_cmp_and_jump_insns (rangertx
, index
, LTU
, NULL_RTX
,
5450 omode
, 1, 0, default_label
);
5451 /* Now we can safely truncate. */
5452 index
= convert_to_mode (index_mode
, index
, 0);
5456 if (TYPE_MODE (index_type
) != index_mode
)
5458 index_expr
= convert (type_for_size (index_bits
, 0),
5460 index_type
= TREE_TYPE (index_expr
);
5463 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5466 index
= protect_from_queue (index
, 0);
5467 do_pending_stack_adjust ();
5469 op_mode
= insn_data
[(int) CODE_FOR_casesi
].operand
[0].mode
;
5470 if (! (*insn_data
[(int) CODE_FOR_casesi
].operand
[0].predicate
)
5472 index
= copy_to_mode_reg (op_mode
, index
);
5474 op1
= expand_expr (minval
, NULL_RTX
, VOIDmode
, 0);
5476 op_mode
= insn_data
[(int) CODE_FOR_casesi
].operand
[1].mode
;
5477 if (! (*insn_data
[(int) CODE_FOR_casesi
].operand
[1].predicate
)
5479 op1
= copy_to_mode_reg (op_mode
, op1
);
5481 op2
= expand_expr (range
, NULL_RTX
, VOIDmode
, 0);
5483 op_mode
= insn_data
[(int) CODE_FOR_casesi
].operand
[2].mode
;
5484 if (! (*insn_data
[(int) CODE_FOR_casesi
].operand
[2].predicate
)
5486 op2
= copy_to_mode_reg (op_mode
, op2
);
5488 emit_jump_insn (gen_casesi (index
, op1
, op2
,
5489 table_label
, default_label
));
5493 #ifdef HAVE_tablejump
5494 if (! win
&& HAVE_tablejump
)
5496 index_type
= thiscase
->data
.case_stmt
.nominal_type
;
5497 index_expr
= fold (build (MINUS_EXPR
, index_type
,
5498 convert (index_type
, index_expr
),
5499 convert (index_type
, minval
)));
5500 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5502 index
= protect_from_queue (index
, 0);
5503 do_pending_stack_adjust ();
5505 do_tablejump (index
, TYPE_MODE (index_type
),
5506 expand_expr (range
, NULL_RTX
, VOIDmode
, 0),
5507 table_label
, default_label
);
5514 /* Get table of labels to jump to, in order of case index. */
5516 ncases
= TREE_INT_CST_LOW (range
) + 1;
5517 labelvec
= (rtx
*) alloca (ncases
* sizeof (rtx
));
5518 memset ((char *) labelvec
, 0, ncases
* sizeof (rtx
));
5520 for (n
= thiscase
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5522 register HOST_WIDE_INT i
5523 = TREE_INT_CST_LOW (n
->low
) - TREE_INT_CST_LOW (orig_minval
);
5528 = gen_rtx_LABEL_REF (Pmode
, label_rtx (n
->code_label
));
5529 if (i
+ TREE_INT_CST_LOW (orig_minval
)
5530 == TREE_INT_CST_LOW (n
->high
))
5536 /* Fill in the gaps with the default. */
5537 for (i
= 0; i
< ncases
; i
++)
5538 if (labelvec
[i
] == 0)
5539 labelvec
[i
] = gen_rtx_LABEL_REF (Pmode
, default_label
);
5541 /* Output the table */
5542 emit_label (table_label
);
5544 if (CASE_VECTOR_PC_RELATIVE
|| flag_pic
)
5545 emit_jump_insn (gen_rtx_ADDR_DIFF_VEC (CASE_VECTOR_MODE
,
5546 gen_rtx_LABEL_REF (Pmode
, table_label
),
5547 gen_rtvec_v (ncases
, labelvec
),
5548 const0_rtx
, const0_rtx
));
5550 emit_jump_insn (gen_rtx_ADDR_VEC (CASE_VECTOR_MODE
,
5551 gen_rtvec_v (ncases
, labelvec
)));
5553 /* If the case insn drops through the table,
5554 after the table we must jump to the default-label.
5555 Otherwise record no drop-through after the table. */
5556 #ifdef CASE_DROPS_THROUGH
5557 emit_jump (default_label
);
5563 before_case
= squeeze_notes (NEXT_INSN (before_case
), get_last_insn ());
5564 reorder_insns (before_case
, get_last_insn (),
5565 thiscase
->data
.case_stmt
.start
);
5568 end_cleanup_deferral ();
5570 if (thiscase
->exit_label
)
5571 emit_label (thiscase
->exit_label
);
5573 free_case_nodes (case_stack
->data
.case_stmt
.case_list
);
5574 POPSTACK (case_stack
);
5579 /* Convert the tree NODE into a list linked by the right field, with the left
5580 field zeroed. RIGHT is used for recursion; it is a list to be placed
5581 rightmost in the resulting list. */
5583 static struct case_node
*
5584 case_tree2list (node
, right
)
5585 struct case_node
*node
, *right
;
5587 struct case_node
*left
;
5590 right
= case_tree2list (node
->right
, right
);
5592 node
->right
= right
;
5593 if ((left
= node
->left
))
5596 return case_tree2list (left
, node
);
5602 /* Generate code to jump to LABEL if OP1 and OP2 are equal. */
5605 do_jump_if_equal (op1
, op2
, label
, unsignedp
)
5606 rtx op1
, op2
, label
;
5609 if (GET_CODE (op1
) == CONST_INT
5610 && GET_CODE (op2
) == CONST_INT
)
5612 if (INTVAL (op1
) == INTVAL (op2
))
5617 enum machine_mode mode
= GET_MODE (op1
);
5618 if (mode
== VOIDmode
)
5619 mode
= GET_MODE (op2
);
5620 emit_cmp_and_jump_insns (op1
, op2
, EQ
, NULL_RTX
, mode
, unsignedp
,
5625 /* Not all case values are encountered equally. This function
5626 uses a heuristic to weight case labels, in cases where that
5627 looks like a reasonable thing to do.
5629 Right now, all we try to guess is text, and we establish the
5632 chars above space: 16
5641 If we find any cases in the switch that are not either -1 or in the range
5642 of valid ASCII characters, or are control characters other than those
5643 commonly used with "\", don't treat this switch scanning text.
5645 Return 1 if these nodes are suitable for cost estimation, otherwise
5649 estimate_case_costs (node
)
5652 tree min_ascii
= integer_minus_one_node
;
5653 tree max_ascii
= convert (TREE_TYPE (node
->high
), build_int_2 (127, 0));
5657 /* If we haven't already made the cost table, make it now. Note that the
5658 lower bound of the table is -1, not zero. */
5660 if (! cost_table_initialized
)
5662 cost_table_initialized
= 1;
5664 for (i
= 0; i
< 128; i
++)
5667 COST_TABLE (i
) = 16;
5668 else if (ISPUNCT (i
))
5670 else if (ISCNTRL (i
))
5671 COST_TABLE (i
) = -1;
5674 COST_TABLE (' ') = 8;
5675 COST_TABLE ('\t') = 4;
5676 COST_TABLE ('\0') = 4;
5677 COST_TABLE ('\n') = 2;
5678 COST_TABLE ('\f') = 1;
5679 COST_TABLE ('\v') = 1;
5680 COST_TABLE ('\b') = 1;
5683 /* See if all the case expressions look like text. It is text if the
5684 constant is >= -1 and the highest constant is <= 127. Do all comparisons
5685 as signed arithmetic since we don't want to ever access cost_table with a
5686 value less than -1. Also check that none of the constants in a range
5687 are strange control characters. */
5689 for (n
= node
; n
; n
= n
->right
)
5691 if ((INT_CST_LT (n
->low
, min_ascii
)) || INT_CST_LT (max_ascii
, n
->high
))
5694 for (i
= (HOST_WIDE_INT
) TREE_INT_CST_LOW (n
->low
);
5695 i
<= (HOST_WIDE_INT
) TREE_INT_CST_LOW (n
->high
); i
++)
5696 if (COST_TABLE (i
) < 0)
5700 /* All interesting values are within the range of interesting
5701 ASCII characters. */
5705 /* Scan an ordered list of case nodes
5706 combining those with consecutive values or ranges.
5708 Eg. three separate entries 1: 2: 3: become one entry 1..3: */
5711 group_case_nodes (head
)
5714 case_node_ptr node
= head
;
5718 rtx lb
= next_real_insn (label_rtx (node
->code_label
));
5720 case_node_ptr np
= node
;
5722 /* Try to group the successors of NODE with NODE. */
5723 while (((np
= np
->right
) != 0)
5724 /* Do they jump to the same place? */
5725 && ((lb2
= next_real_insn (label_rtx (np
->code_label
))) == lb
5726 || (lb
!= 0 && lb2
!= 0
5727 && simplejump_p (lb
)
5728 && simplejump_p (lb2
)
5729 && rtx_equal_p (SET_SRC (PATTERN (lb
)),
5730 SET_SRC (PATTERN (lb2
)))))
5731 /* Are their ranges consecutive? */
5732 && tree_int_cst_equal (np
->low
,
5733 fold (build (PLUS_EXPR
,
5734 TREE_TYPE (node
->high
),
5737 /* An overflow is not consecutive. */
5738 && tree_int_cst_lt (node
->high
,
5739 fold (build (PLUS_EXPR
,
5740 TREE_TYPE (node
->high
),
5742 integer_one_node
))))
5744 node
->high
= np
->high
;
5746 /* NP is the first node after NODE which can't be grouped with it.
5747 Delete the nodes in between, and move on to that node. */
5753 /* Take an ordered list of case nodes
5754 and transform them into a near optimal binary tree,
5755 on the assumption that any target code selection value is as
5756 likely as any other.
5758 The transformation is performed by splitting the ordered
5759 list into two equal sections plus a pivot. The parts are
5760 then attached to the pivot as left and right branches. Each
5761 branch is then transformed recursively. */
5764 balance_case_nodes (head
, parent
)
5765 case_node_ptr
*head
;
5766 case_node_ptr parent
;
5768 register case_node_ptr np
;
5776 register case_node_ptr
*npp
;
5779 /* Count the number of entries on branch. Also count the ranges. */
5783 if (!tree_int_cst_equal (np
->low
, np
->high
))
5787 cost
+= COST_TABLE (TREE_INT_CST_LOW (np
->high
));
5791 cost
+= COST_TABLE (TREE_INT_CST_LOW (np
->low
));
5799 /* Split this list if it is long enough for that to help. */
5804 /* Find the place in the list that bisects the list's total cost,
5805 Here I gets half the total cost. */
5810 /* Skip nodes while their cost does not reach that amount. */
5811 if (!tree_int_cst_equal ((*npp
)->low
, (*npp
)->high
))
5812 i
-= COST_TABLE (TREE_INT_CST_LOW ((*npp
)->high
));
5813 i
-= COST_TABLE (TREE_INT_CST_LOW ((*npp
)->low
));
5816 npp
= &(*npp
)->right
;
5821 /* Leave this branch lopsided, but optimize left-hand
5822 side and fill in `parent' fields for right-hand side. */
5824 np
->parent
= parent
;
5825 balance_case_nodes (&np
->left
, np
);
5826 for (; np
->right
; np
= np
->right
)
5827 np
->right
->parent
= np
;
5831 /* If there are just three nodes, split at the middle one. */
5833 npp
= &(*npp
)->right
;
5836 /* Find the place in the list that bisects the list's total cost,
5837 where ranges count as 2.
5838 Here I gets half the total cost. */
5839 i
= (i
+ ranges
+ 1) / 2;
5842 /* Skip nodes while their cost does not reach that amount. */
5843 if (!tree_int_cst_equal ((*npp
)->low
, (*npp
)->high
))
5848 npp
= &(*npp
)->right
;
5853 np
->parent
= parent
;
5856 /* Optimize each of the two split parts. */
5857 balance_case_nodes (&np
->left
, np
);
5858 balance_case_nodes (&np
->right
, np
);
5862 /* Else leave this branch as one level,
5863 but fill in `parent' fields. */
5865 np
->parent
= parent
;
5866 for (; np
->right
; np
= np
->right
)
5867 np
->right
->parent
= np
;
5872 /* Search the parent sections of the case node tree
5873 to see if a test for the lower bound of NODE would be redundant.
5874 INDEX_TYPE is the type of the index expression.
5876 The instructions to generate the case decision tree are
5877 output in the same order as nodes are processed so it is
5878 known that if a parent node checks the range of the current
5879 node minus one that the current node is bounded at its lower
5880 span. Thus the test would be redundant. */
5883 node_has_low_bound (node
, index_type
)
5888 case_node_ptr pnode
;
5890 /* If the lower bound of this node is the lowest value in the index type,
5891 we need not test it. */
5893 if (tree_int_cst_equal (node
->low
, TYPE_MIN_VALUE (index_type
)))
5896 /* If this node has a left branch, the value at the left must be less
5897 than that at this node, so it cannot be bounded at the bottom and
5898 we need not bother testing any further. */
5903 low_minus_one
= fold (build (MINUS_EXPR
, TREE_TYPE (node
->low
),
5904 node
->low
, integer_one_node
));
5906 /* If the subtraction above overflowed, we can't verify anything.
5907 Otherwise, look for a parent that tests our value - 1. */
5909 if (! tree_int_cst_lt (low_minus_one
, node
->low
))
5912 for (pnode
= node
->parent
; pnode
; pnode
= pnode
->parent
)
5913 if (tree_int_cst_equal (low_minus_one
, pnode
->high
))
5919 /* Search the parent sections of the case node tree
5920 to see if a test for the upper bound of NODE would be redundant.
5921 INDEX_TYPE is the type of the index expression.
5923 The instructions to generate the case decision tree are
5924 output in the same order as nodes are processed so it is
5925 known that if a parent node checks the range of the current
5926 node plus one that the current node is bounded at its upper
5927 span. Thus the test would be redundant. */
5930 node_has_high_bound (node
, index_type
)
5935 case_node_ptr pnode
;
5937 /* If there is no upper bound, obviously no test is needed. */
5939 if (TYPE_MAX_VALUE (index_type
) == NULL
)
5942 /* If the upper bound of this node is the highest value in the type
5943 of the index expression, we need not test against it. */
5945 if (tree_int_cst_equal (node
->high
, TYPE_MAX_VALUE (index_type
)))
5948 /* If this node has a right branch, the value at the right must be greater
5949 than that at this node, so it cannot be bounded at the top and
5950 we need not bother testing any further. */
5955 high_plus_one
= fold (build (PLUS_EXPR
, TREE_TYPE (node
->high
),
5956 node
->high
, integer_one_node
));
5958 /* If the addition above overflowed, we can't verify anything.
5959 Otherwise, look for a parent that tests our value + 1. */
5961 if (! tree_int_cst_lt (node
->high
, high_plus_one
))
5964 for (pnode
= node
->parent
; pnode
; pnode
= pnode
->parent
)
5965 if (tree_int_cst_equal (high_plus_one
, pnode
->low
))
5971 /* Search the parent sections of the
5972 case node tree to see if both tests for the upper and lower
5973 bounds of NODE would be redundant. */
5976 node_is_bounded (node
, index_type
)
5980 return (node_has_low_bound (node
, index_type
)
5981 && node_has_high_bound (node
, index_type
));
5984 /* Emit an unconditional jump to LABEL unless it would be dead code. */
5987 emit_jump_if_reachable (label
)
5990 if (GET_CODE (get_last_insn ()) != BARRIER
)
5994 /* Emit step-by-step code to select a case for the value of INDEX.
5995 The thus generated decision tree follows the form of the
5996 case-node binary tree NODE, whose nodes represent test conditions.
5997 INDEX_TYPE is the type of the index of the switch.
5999 Care is taken to prune redundant tests from the decision tree
6000 by detecting any boundary conditions already checked by
6001 emitted rtx. (See node_has_high_bound, node_has_low_bound
6002 and node_is_bounded, above.)
6004 Where the test conditions can be shown to be redundant we emit
6005 an unconditional jump to the target code. As a further
6006 optimization, the subordinates of a tree node are examined to
6007 check for bounded nodes. In this case conditional and/or
6008 unconditional jumps as a result of the boundary check for the
6009 current node are arranged to target the subordinates associated
6010 code for out of bound conditions on the current node.
6012 We can assume that when control reaches the code generated here,
6013 the index value has already been compared with the parents
6014 of this node, and determined to be on the same side of each parent
6015 as this node is. Thus, if this node tests for the value 51,
6016 and a parent tested for 52, we don't need to consider
6017 the possibility of a value greater than 51. If another parent
6018 tests for the value 50, then this node need not test anything. */
6021 emit_case_nodes (index
, node
, default_label
, index_type
)
6027 /* If INDEX has an unsigned type, we must make unsigned branches. */
6028 int unsignedp
= TREE_UNSIGNED (index_type
);
6029 enum machine_mode mode
= GET_MODE (index
);
6031 /* See if our parents have already tested everything for us.
6032 If they have, emit an unconditional jump for this node. */
6033 if (node_is_bounded (node
, index_type
))
6034 emit_jump (label_rtx (node
->code_label
));
6036 else if (tree_int_cst_equal (node
->low
, node
->high
))
6038 /* Node is single valued. First see if the index expression matches
6039 this node and then check our children, if any. */
6041 do_jump_if_equal (index
, expand_expr (node
->low
, NULL_RTX
, VOIDmode
, 0),
6042 label_rtx (node
->code_label
), unsignedp
);
6044 if (node
->right
!= 0 && node
->left
!= 0)
6046 /* This node has children on both sides.
6047 Dispatch to one side or the other
6048 by comparing the index value with this node's value.
6049 If one subtree is bounded, check that one first,
6050 so we can avoid real branches in the tree. */
6052 if (node_is_bounded (node
->right
, index_type
))
6054 emit_cmp_and_jump_insns (index
,
6055 expand_expr (node
->high
, NULL_RTX
,
6057 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6058 label_rtx (node
->right
->code_label
));
6059 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6062 else if (node_is_bounded (node
->left
, index_type
))
6064 emit_cmp_and_jump_insns (index
,
6065 expand_expr (node
->high
, NULL_RTX
,
6067 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6068 label_rtx (node
->left
->code_label
));
6069 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6074 /* Neither node is bounded. First distinguish the two sides;
6075 then emit the code for one side at a time. */
6077 tree test_label
= build_decl (LABEL_DECL
, NULL_TREE
, NULL_TREE
);
6079 /* See if the value is on the right. */
6080 emit_cmp_and_jump_insns (index
,
6081 expand_expr (node
->high
, NULL_RTX
,
6083 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6084 label_rtx (test_label
));
6086 /* Value must be on the left.
6087 Handle the left-hand subtree. */
6088 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6089 /* If left-hand subtree does nothing,
6091 emit_jump_if_reachable (default_label
);
6093 /* Code branches here for the right-hand subtree. */
6094 expand_label (test_label
);
6095 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6099 else if (node
->right
!= 0 && node
->left
== 0)
6101 /* Here we have a right child but no left so we issue conditional
6102 branch to default and process the right child.
6104 Omit the conditional branch to default if we it avoid only one
6105 right child; it costs too much space to save so little time. */
6107 if (node
->right
->right
|| node
->right
->left
6108 || !tree_int_cst_equal (node
->right
->low
, node
->right
->high
))
6110 if (!node_has_low_bound (node
, index_type
))
6112 emit_cmp_and_jump_insns (index
,
6113 expand_expr (node
->high
, NULL_RTX
,
6115 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6119 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6122 /* We cannot process node->right normally
6123 since we haven't ruled out the numbers less than
6124 this node's value. So handle node->right explicitly. */
6125 do_jump_if_equal (index
,
6126 expand_expr (node
->right
->low
, NULL_RTX
,
6128 label_rtx (node
->right
->code_label
), unsignedp
);
6131 else if (node
->right
== 0 && node
->left
!= 0)
6133 /* Just one subtree, on the left. */
6135 #if 0 /* The following code and comment were formerly part
6136 of the condition here, but they didn't work
6137 and I don't understand what the idea was. -- rms. */
6138 /* If our "most probable entry" is less probable
6139 than the default label, emit a jump to
6140 the default label using condition codes
6141 already lying around. With no right branch,
6142 a branch-greater-than will get us to the default
6145 && COST_TABLE (TREE_INT_CST_LOW (node
->high
)) < 12)
6148 if (node
->left
->left
|| node
->left
->right
6149 || !tree_int_cst_equal (node
->left
->low
, node
->left
->high
))
6151 if (!node_has_high_bound (node
, index_type
))
6153 emit_cmp_and_jump_insns (index
, expand_expr (node
->high
,
6156 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6160 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6163 /* We cannot process node->left normally
6164 since we haven't ruled out the numbers less than
6165 this node's value. So handle node->left explicitly. */
6166 do_jump_if_equal (index
,
6167 expand_expr (node
->left
->low
, NULL_RTX
,
6169 label_rtx (node
->left
->code_label
), unsignedp
);
6174 /* Node is a range. These cases are very similar to those for a single
6175 value, except that we do not start by testing whether this node
6176 is the one to branch to. */
6178 if (node
->right
!= 0 && node
->left
!= 0)
6180 /* Node has subtrees on both sides.
6181 If the right-hand subtree is bounded,
6182 test for it first, since we can go straight there.
6183 Otherwise, we need to make a branch in the control structure,
6184 then handle the two subtrees. */
6185 tree test_label
= 0;
6187 if (node_is_bounded (node
->right
, index_type
))
6188 /* Right hand node is fully bounded so we can eliminate any
6189 testing and branch directly to the target code. */
6190 emit_cmp_and_jump_insns (index
, expand_expr (node
->high
, NULL_RTX
,
6192 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6193 label_rtx (node
->right
->code_label
));
6196 /* Right hand node requires testing.
6197 Branch to a label where we will handle it later. */
6199 test_label
= build_decl (LABEL_DECL
, NULL_TREE
, NULL_TREE
);
6200 emit_cmp_and_jump_insns (index
,
6201 expand_expr (node
->high
, NULL_RTX
,
6203 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6204 label_rtx (test_label
));
6207 /* Value belongs to this node or to the left-hand subtree. */
6209 emit_cmp_and_jump_insns (index
, expand_expr (node
->low
, NULL_RTX
,
6211 GE
, NULL_RTX
, mode
, unsignedp
, 0,
6212 label_rtx (node
->code_label
));
6214 /* Handle the left-hand subtree. */
6215 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6217 /* If right node had to be handled later, do that now. */
6221 /* If the left-hand subtree fell through,
6222 don't let it fall into the right-hand subtree. */
6223 emit_jump_if_reachable (default_label
);
6225 expand_label (test_label
);
6226 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6230 else if (node
->right
!= 0 && node
->left
== 0)
6232 /* Deal with values to the left of this node,
6233 if they are possible. */
6234 if (!node_has_low_bound (node
, index_type
))
6236 emit_cmp_and_jump_insns (index
,
6237 expand_expr (node
->low
, NULL_RTX
,
6239 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6243 /* Value belongs to this node or to the right-hand subtree. */
6245 emit_cmp_and_jump_insns (index
, expand_expr (node
->high
, NULL_RTX
,
6247 LE
, NULL_RTX
, mode
, unsignedp
, 0,
6248 label_rtx (node
->code_label
));
6250 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6253 else if (node
->right
== 0 && node
->left
!= 0)
6255 /* Deal with values to the right of this node,
6256 if they are possible. */
6257 if (!node_has_high_bound (node
, index_type
))
6259 emit_cmp_and_jump_insns (index
,
6260 expand_expr (node
->high
, NULL_RTX
,
6262 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6266 /* Value belongs to this node or to the left-hand subtree. */
6268 emit_cmp_and_jump_insns (index
,
6269 expand_expr (node
->low
, NULL_RTX
,
6271 GE
, NULL_RTX
, mode
, unsignedp
, 0,
6272 label_rtx (node
->code_label
));
6274 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6279 /* Node has no children so we check low and high bounds to remove
6280 redundant tests. Only one of the bounds can exist,
6281 since otherwise this node is bounded--a case tested already. */
6283 if (!node_has_high_bound (node
, index_type
))
6285 emit_cmp_and_jump_insns (index
,
6286 expand_expr (node
->high
, NULL_RTX
,
6288 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6292 if (!node_has_low_bound (node
, index_type
))
6294 emit_cmp_and_jump_insns (index
,
6295 expand_expr (node
->low
, NULL_RTX
,
6297 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6301 emit_jump (label_rtx (node
->code_label
));