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, 2001 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"
49 #include "hard-reg-set.h"
58 #define obstack_chunk_alloc xmalloc
59 #define obstack_chunk_free free
60 struct obstack stmt_obstack
;
62 /* Assume that case vectors are not pc-relative. */
63 #ifndef CASE_VECTOR_PC_RELATIVE
64 #define CASE_VECTOR_PC_RELATIVE 0
67 /* Functions and data structures for expanding case statements. */
69 /* Case label structure, used to hold info on labels within case
70 statements. We handle "range" labels; for a single-value label
71 as in C, the high and low limits are the same.
73 An AVL tree of case nodes is initially created, and later transformed
74 to a list linked via the RIGHT fields in the nodes. Nodes with
75 higher case values are later in the list.
77 Switch statements can be output in one of two forms. A branch table
78 is used if there are more than a few labels and the labels are dense
79 within the range between the smallest and largest case value. If a
80 branch table is used, no further manipulations are done with the case
83 The alternative to the use of a branch table is to generate a series
84 of compare and jump insns. When that is done, we use the LEFT, RIGHT,
85 and PARENT fields to hold a binary tree. Initially the tree is
86 totally unbalanced, with everything on the right. We balance the tree
87 with nodes on the left having lower case values than the parent
88 and nodes on the right having higher values. We then output the tree
93 struct case_node
*left
; /* Left son in binary tree */
94 struct case_node
*right
; /* Right son in binary tree; also node chain */
95 struct case_node
*parent
; /* Parent of node in binary tree */
96 tree low
; /* Lowest index value for this label */
97 tree high
; /* Highest index value for this label */
98 tree code_label
; /* Label to jump to when node matches */
102 typedef struct case_node case_node
;
103 typedef struct case_node
*case_node_ptr
;
105 /* These are used by estimate_case_costs and balance_case_nodes. */
107 /* This must be a signed type, and non-ANSI compilers lack signed char. */
108 static short cost_table_
[129];
109 static int use_cost_table
;
110 static int cost_table_initialized
;
112 /* Special care is needed because we allow -1, but TREE_INT_CST_LOW
114 #define COST_TABLE(I) cost_table_[(unsigned HOST_WIDE_INT)((I) + 1)]
116 /* Stack of control and binding constructs we are currently inside.
118 These constructs begin when you call `expand_start_WHATEVER'
119 and end when you call `expand_end_WHATEVER'. This stack records
120 info about how the construct began that tells the end-function
121 what to do. It also may provide information about the construct
122 to alter the behavior of other constructs within the body.
123 For example, they may affect the behavior of C `break' and `continue'.
125 Each construct gets one `struct nesting' object.
126 All of these objects are chained through the `all' field.
127 `nesting_stack' points to the first object (innermost construct).
128 The position of an entry on `nesting_stack' is in its `depth' field.
130 Each type of construct has its own individual stack.
131 For example, loops have `loop_stack'. Each object points to the
132 next object of the same type through the `next' field.
134 Some constructs are visible to `break' exit-statements and others
135 are not. Which constructs are visible depends on the language.
136 Therefore, the data structure allows each construct to be visible
137 or not, according to the args given when the construct is started.
138 The construct is visible if the `exit_label' field is non-null.
139 In that case, the value should be a CODE_LABEL rtx. */
144 struct nesting
*next
;
149 /* For conds (if-then and if-then-else statements). */
152 /* Label for the end of the if construct.
153 There is none if EXITFLAG was not set
154 and no `else' has been seen yet. */
156 /* Label for the end of this alternative.
157 This may be the end of the if or the next else/elseif. */
163 /* Label at the top of the loop; place to loop back to. */
165 /* Label at the end of the whole construct. */
167 /* Label before a jump that branches to the end of the whole
168 construct. This is where destructors go if any. */
170 /* Label for `continue' statement to jump to;
171 this is in front of the stepper of the loop. */
174 /* For variable binding contours. */
177 /* Sequence number of this binding contour within the function,
178 in order of entry. */
179 int block_start_count
;
180 /* Nonzero => value to restore stack to on exit. */
182 /* The NOTE that starts this contour.
183 Used by expand_goto to check whether the destination
184 is within each contour or not. */
186 /* Innermost containing binding contour that has a stack level. */
187 struct nesting
*innermost_stack_block
;
188 /* List of cleanups to be run on exit from this contour.
189 This is a list of expressions to be evaluated.
190 The TREE_PURPOSE of each link is the ..._DECL node
191 which the cleanup pertains to. */
193 /* List of cleanup-lists of blocks containing this block,
194 as they were at the locus where this block appears.
195 There is an element for each containing block,
196 ordered innermost containing block first.
197 The tail of this list can be 0,
198 if all remaining elements would be empty lists.
199 The element's TREE_VALUE is the cleanup-list of that block,
200 which may be null. */
202 /* Chain of labels defined inside this binding contour.
203 For contours that have stack levels or cleanups. */
204 struct label_chain
*label_chain
;
205 /* Number of function calls seen, as of start of this block. */
206 int n_function_calls
;
207 /* Nonzero if this is associated with a EH region. */
208 int exception_region
;
209 /* The saved target_temp_slot_level from our outer block.
210 We may reset target_temp_slot_level to be the level of
211 this block, if that is done, target_temp_slot_level
212 reverts to the saved target_temp_slot_level at the very
214 int block_target_temp_slot_level
;
215 /* True if we are currently emitting insns in an area of
216 output code that is controlled by a conditional
217 expression. This is used by the cleanup handling code to
218 generate conditional cleanup actions. */
219 int conditional_code
;
220 /* A place to move the start of the exception region for any
221 of the conditional cleanups, must be at the end or after
222 the start of the last unconditional cleanup, and before any
223 conditional branch points. */
224 rtx last_unconditional_cleanup
;
225 /* When in a conditional context, this is the specific
226 cleanup list associated with last_unconditional_cleanup,
227 where we place the conditionalized cleanups. */
230 /* For switch (C) or case (Pascal) statements,
231 and also for dummies (see `expand_start_case_dummy'). */
234 /* The insn after which the case dispatch should finally
235 be emitted. Zero for a dummy. */
237 /* A list of case labels; it is first built as an AVL tree.
238 During expand_end_case, this is converted to a list, and may be
239 rearranged into a nearly balanced binary tree. */
240 struct case_node
*case_list
;
241 /* Label to jump to if no case matches. */
243 /* The expression to be dispatched on. */
245 /* Type that INDEX_EXPR should be converted to. */
247 /* Name of this kind of statement, for warnings. */
248 const char *printname
;
249 /* Used to save no_line_numbers till we see the first case label.
250 We set this to -1 when we see the first case label in this
252 int line_number_status
;
257 /* Allocate and return a new `struct nesting'. */
259 #define ALLOC_NESTING() \
260 (struct nesting *) obstack_alloc (&stmt_obstack, sizeof (struct nesting))
262 /* Pop the nesting stack element by element until we pop off
263 the element which is at the top of STACK.
264 Update all the other stacks, popping off elements from them
265 as we pop them from nesting_stack. */
267 #define POPSTACK(STACK) \
268 do { struct nesting *target = STACK; \
269 struct nesting *this; \
270 do { this = nesting_stack; \
271 if (loop_stack == this) \
272 loop_stack = loop_stack->next; \
273 if (cond_stack == this) \
274 cond_stack = cond_stack->next; \
275 if (block_stack == this) \
276 block_stack = block_stack->next; \
277 if (stack_block_stack == this) \
278 stack_block_stack = stack_block_stack->next; \
279 if (case_stack == this) \
280 case_stack = case_stack->next; \
281 nesting_depth = nesting_stack->depth - 1; \
282 nesting_stack = this->all; \
283 obstack_free (&stmt_obstack, this); } \
284 while (this != target); } while (0)
286 /* In some cases it is impossible to generate code for a forward goto
287 until the label definition is seen. This happens when it may be necessary
288 for the goto to reset the stack pointer: we don't yet know how to do that.
289 So expand_goto puts an entry on this fixup list.
290 Each time a binding contour that resets the stack is exited,
292 If the target label has now been defined, we can insert the proper code. */
296 /* Points to following fixup. */
297 struct goto_fixup
*next
;
298 /* Points to the insn before the jump insn.
299 If more code must be inserted, it goes after this insn. */
301 /* The LABEL_DECL that this jump is jumping to, or 0
302 for break, continue or return. */
304 /* The BLOCK for the place where this goto was found. */
306 /* The CODE_LABEL rtx that this is jumping to. */
308 /* Number of binding contours started in current function
309 before the label reference. */
310 int block_start_count
;
311 /* The outermost stack level that should be restored for this jump.
312 Each time a binding contour that resets the stack is exited,
313 if the target label is *not* yet defined, this slot is updated. */
315 /* List of lists of cleanup expressions to be run by this goto.
316 There is one element for each block that this goto is within.
317 The tail of this list can be 0,
318 if all remaining elements would be empty.
319 The TREE_VALUE contains the cleanup list of that block as of the
320 time this goto was seen.
321 The TREE_ADDRESSABLE flag is 1 for a block that has been exited. */
322 tree cleanup_list_list
;
325 /* Within any binding contour that must restore a stack level,
326 all labels are recorded with a chain of these structures. */
330 /* Points to following fixup. */
331 struct label_chain
*next
;
337 /* Chain of all pending binding contours. */
338 struct nesting
*x_block_stack
;
340 /* If any new stacks are added here, add them to POPSTACKS too. */
342 /* Chain of all pending binding contours that restore stack levels
344 struct nesting
*x_stack_block_stack
;
346 /* Chain of all pending conditional statements. */
347 struct nesting
*x_cond_stack
;
349 /* Chain of all pending loops. */
350 struct nesting
*x_loop_stack
;
352 /* Chain of all pending case or switch statements. */
353 struct nesting
*x_case_stack
;
355 /* Separate chain including all of the above,
356 chained through the `all' field. */
357 struct nesting
*x_nesting_stack
;
359 /* Number of entries on nesting_stack now. */
362 /* Number of binding contours started so far in this function. */
363 int x_block_start_count
;
365 /* Each time we expand an expression-statement,
366 record the expr's type and its RTL value here. */
367 tree x_last_expr_type
;
368 rtx x_last_expr_value
;
370 /* Nonzero if within a ({...}) grouping, in which case we must
371 always compute a value for each expr-stmt in case it is the last one. */
372 int x_expr_stmts_for_value
;
374 /* Filename and line number of last line-number note,
375 whether we actually emitted it or not. */
376 const char *x_emit_filename
;
379 struct goto_fixup
*x_goto_fixup_chain
;
382 #define block_stack (cfun->stmt->x_block_stack)
383 #define stack_block_stack (cfun->stmt->x_stack_block_stack)
384 #define cond_stack (cfun->stmt->x_cond_stack)
385 #define loop_stack (cfun->stmt->x_loop_stack)
386 #define case_stack (cfun->stmt->x_case_stack)
387 #define nesting_stack (cfun->stmt->x_nesting_stack)
388 #define nesting_depth (cfun->stmt->x_nesting_depth)
389 #define current_block_start_count (cfun->stmt->x_block_start_count)
390 #define last_expr_type (cfun->stmt->x_last_expr_type)
391 #define last_expr_value (cfun->stmt->x_last_expr_value)
392 #define expr_stmts_for_value (cfun->stmt->x_expr_stmts_for_value)
393 #define emit_filename (cfun->stmt->x_emit_filename)
394 #define emit_lineno (cfun->stmt->x_emit_lineno)
395 #define goto_fixup_chain (cfun->stmt->x_goto_fixup_chain)
397 /* Non-zero if we are using EH to handle cleanus. */
398 static int using_eh_for_cleanups_p
= 0;
400 static int n_occurrences
PARAMS ((int, const char *));
401 static void expand_goto_internal
PARAMS ((tree
, rtx
, rtx
));
402 static int expand_fixup
PARAMS ((tree
, rtx
, rtx
));
403 static rtx expand_nl_handler_label
PARAMS ((rtx
, rtx
));
404 static void expand_nl_goto_receiver
PARAMS ((void));
405 static void expand_nl_goto_receivers
PARAMS ((struct nesting
*));
406 static void fixup_gotos
PARAMS ((struct nesting
*, rtx
, tree
,
408 static void expand_null_return_1
PARAMS ((rtx
));
409 static void expand_value_return
PARAMS ((rtx
));
410 static int tail_recursion_args
PARAMS ((tree
, tree
));
411 static void expand_cleanups
PARAMS ((tree
, tree
, int, int));
412 static void check_seenlabel
PARAMS ((void));
413 static void do_jump_if_equal
PARAMS ((rtx
, rtx
, rtx
, int));
414 static int estimate_case_costs
PARAMS ((case_node_ptr
));
415 static void group_case_nodes
PARAMS ((case_node_ptr
));
416 static void balance_case_nodes
PARAMS ((case_node_ptr
*,
418 static int node_has_low_bound
PARAMS ((case_node_ptr
, tree
));
419 static int node_has_high_bound
PARAMS ((case_node_ptr
, tree
));
420 static int node_is_bounded
PARAMS ((case_node_ptr
, tree
));
421 static void emit_jump_if_reachable
PARAMS ((rtx
));
422 static void emit_case_nodes
PARAMS ((rtx
, case_node_ptr
, rtx
, tree
));
423 static struct case_node
*case_tree2list
PARAMS ((case_node
*, case_node
*));
424 static void mark_cond_nesting
PARAMS ((struct nesting
*));
425 static void mark_loop_nesting
PARAMS ((struct nesting
*));
426 static void mark_block_nesting
PARAMS ((struct nesting
*));
427 static void mark_case_nesting
PARAMS ((struct nesting
*));
428 static void mark_case_node
PARAMS ((struct case_node
*));
429 static void mark_goto_fixup
PARAMS ((struct goto_fixup
*));
430 static void free_case_nodes
PARAMS ((case_node_ptr
));
433 using_eh_for_cleanups ()
435 using_eh_for_cleanups_p
= 1;
438 /* Mark N (known to be a cond-nesting) for GC. */
441 mark_cond_nesting (n
)
446 ggc_mark_rtx (n
->exit_label
);
447 ggc_mark_rtx (n
->data
.cond
.endif_label
);
448 ggc_mark_rtx (n
->data
.cond
.next_label
);
454 /* Mark N (known to be a loop-nesting) for GC. */
457 mark_loop_nesting (n
)
463 ggc_mark_rtx (n
->exit_label
);
464 ggc_mark_rtx (n
->data
.loop
.start_label
);
465 ggc_mark_rtx (n
->data
.loop
.end_label
);
466 ggc_mark_rtx (n
->data
.loop
.alt_end_label
);
467 ggc_mark_rtx (n
->data
.loop
.continue_label
);
473 /* Mark N (known to be a block-nesting) for GC. */
476 mark_block_nesting (n
)
481 struct label_chain
*l
;
483 ggc_mark_rtx (n
->exit_label
);
484 ggc_mark_rtx (n
->data
.block
.stack_level
);
485 ggc_mark_rtx (n
->data
.block
.first_insn
);
486 ggc_mark_tree (n
->data
.block
.cleanups
);
487 ggc_mark_tree (n
->data
.block
.outer_cleanups
);
489 for (l
= n
->data
.block
.label_chain
; l
!= NULL
; l
= l
->next
)
492 ggc_mark_tree (l
->label
);
495 ggc_mark_rtx (n
->data
.block
.last_unconditional_cleanup
);
497 /* ??? cleanup_ptr never points outside the stack, does it? */
503 /* Mark N (known to be a case-nesting) for GC. */
506 mark_case_nesting (n
)
511 ggc_mark_rtx (n
->exit_label
);
512 ggc_mark_rtx (n
->data
.case_stmt
.start
);
514 ggc_mark_tree (n
->data
.case_stmt
.default_label
);
515 ggc_mark_tree (n
->data
.case_stmt
.index_expr
);
516 ggc_mark_tree (n
->data
.case_stmt
.nominal_type
);
518 mark_case_node (n
->data
.case_stmt
.case_list
);
531 ggc_mark_tree (c
->low
);
532 ggc_mark_tree (c
->high
);
533 ggc_mark_tree (c
->code_label
);
535 mark_case_node (c
->right
);
536 mark_case_node (c
->left
);
544 struct goto_fixup
*g
;
549 ggc_mark_rtx (g
->before_jump
);
550 ggc_mark_tree (g
->target
);
551 ggc_mark_tree (g
->context
);
552 ggc_mark_rtx (g
->target_rtl
);
553 ggc_mark_rtx (g
->stack_level
);
554 ggc_mark_tree (g
->cleanup_list_list
);
560 /* Clear out all parts of the state in F that can safely be discarded
561 after the function has been compiled, to let garbage collection
562 reclaim the memory. */
568 /* We're about to free the function obstack. If we hold pointers to
569 things allocated there, then we'll try to mark them when we do
570 GC. So, we clear them out here explicitly. */
580 struct stmt_status
*p
;
585 mark_block_nesting (p
->x_block_stack
);
586 mark_cond_nesting (p
->x_cond_stack
);
587 mark_loop_nesting (p
->x_loop_stack
);
588 mark_case_nesting (p
->x_case_stack
);
590 ggc_mark_tree (p
->x_last_expr_type
);
591 /* last_epxr_value is only valid if last_expr_type is nonzero. */
592 if (p
->x_last_expr_type
)
593 ggc_mark_rtx (p
->x_last_expr_value
);
595 mark_goto_fixup (p
->x_goto_fixup_chain
);
601 gcc_obstack_init (&stmt_obstack
);
605 init_stmt_for_function ()
607 cfun
->stmt
= (struct stmt_status
*) xmalloc (sizeof (struct stmt_status
));
609 /* We are not currently within any block, conditional, loop or case. */
611 stack_block_stack
= 0;
618 current_block_start_count
= 0;
620 /* No gotos have been expanded yet. */
621 goto_fixup_chain
= 0;
623 /* We are not processing a ({...}) grouping. */
624 expr_stmts_for_value
= 0;
626 last_expr_value
= NULL_RTX
;
629 /* Return nonzero if anything is pushed on the loop, condition, or case
634 return cond_stack
|| loop_stack
|| case_stack
;
637 /* Record the current file and line. Called from emit_line_note. */
639 set_file_and_line_for_stmt (file
, line
)
643 /* If we're outputting an inline function, and we add a line note,
644 there may be no CFUN->STMT information. So, there's no need to
648 emit_filename
= file
;
653 /* Emit a no-op instruction. */
660 last_insn
= get_last_insn ();
662 && (GET_CODE (last_insn
) == CODE_LABEL
663 || (GET_CODE (last_insn
) == NOTE
664 && prev_real_insn (last_insn
) == 0)))
665 emit_insn (gen_nop ());
668 /* Return the rtx-label that corresponds to a LABEL_DECL,
669 creating it if necessary. */
675 if (TREE_CODE (label
) != LABEL_DECL
)
678 if (!DECL_RTL_SET_P (label
))
679 SET_DECL_RTL (label
, gen_label_rtx ());
681 return DECL_RTL (label
);
685 /* Add an unconditional jump to LABEL as the next sequential instruction. */
691 do_pending_stack_adjust ();
692 emit_jump_insn (gen_jump (label
));
696 /* Emit code to jump to the address
697 specified by the pointer expression EXP. */
700 expand_computed_goto (exp
)
703 rtx x
= expand_expr (exp
, NULL_RTX
, VOIDmode
, 0);
705 #ifdef POINTERS_EXTEND_UNSIGNED
706 x
= convert_memory_address (Pmode
, x
);
710 /* Be sure the function is executable. */
711 if (current_function_check_memory_usage
)
712 emit_library_call (chkr_check_exec_libfunc
, LCT_CONST_MAKE_BLOCK
,
713 VOIDmode
, 1, x
, ptr_mode
);
715 do_pending_stack_adjust ();
716 emit_indirect_jump (x
);
718 current_function_has_computed_jump
= 1;
721 /* Handle goto statements and the labels that they can go to. */
723 /* Specify the location in the RTL code of a label LABEL,
724 which is a LABEL_DECL tree node.
726 This is used for the kind of label that the user can jump to with a
727 goto statement, and for alternatives of a switch or case statement.
728 RTL labels generated for loops and conditionals don't go through here;
729 they are generated directly at the RTL level, by other functions below.
731 Note that this has nothing to do with defining label *names*.
732 Languages vary in how they do that and what that even means. */
738 struct label_chain
*p
;
740 do_pending_stack_adjust ();
741 emit_label (label_rtx (label
));
742 if (DECL_NAME (label
))
743 LABEL_NAME (DECL_RTL (label
)) = IDENTIFIER_POINTER (DECL_NAME (label
));
745 if (stack_block_stack
!= 0)
747 p
= (struct label_chain
*) ggc_alloc (sizeof (struct label_chain
));
748 p
->next
= stack_block_stack
->data
.block
.label_chain
;
749 stack_block_stack
->data
.block
.label_chain
= p
;
754 /* Declare that LABEL (a LABEL_DECL) may be used for nonlocal gotos
755 from nested functions. */
758 declare_nonlocal_label (label
)
761 rtx slot
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
763 nonlocal_labels
= tree_cons (NULL_TREE
, label
, nonlocal_labels
);
764 LABEL_PRESERVE_P (label_rtx (label
)) = 1;
765 if (nonlocal_goto_handler_slots
== 0)
767 emit_stack_save (SAVE_NONLOCAL
,
768 &nonlocal_goto_stack_level
,
769 PREV_INSN (tail_recursion_reentry
));
771 nonlocal_goto_handler_slots
772 = gen_rtx_EXPR_LIST (VOIDmode
, slot
, nonlocal_goto_handler_slots
);
775 /* Generate RTL code for a `goto' statement with target label LABEL.
776 LABEL should be a LABEL_DECL tree node that was or will later be
777 defined with `expand_label'. */
785 /* Check for a nonlocal goto to a containing function. */
786 context
= decl_function_context (label
);
787 if (context
!= 0 && context
!= current_function_decl
)
789 struct function
*p
= find_function_data (context
);
790 rtx label_ref
= gen_rtx_LABEL_REF (Pmode
, label_rtx (label
));
791 rtx handler_slot
, static_chain
, save_area
, insn
;
794 /* Find the corresponding handler slot for this label. */
795 handler_slot
= p
->x_nonlocal_goto_handler_slots
;
796 for (link
= p
->x_nonlocal_labels
; TREE_VALUE (link
) != label
;
797 link
= TREE_CHAIN (link
))
798 handler_slot
= XEXP (handler_slot
, 1);
799 handler_slot
= XEXP (handler_slot
, 0);
801 p
->has_nonlocal_label
= 1;
802 current_function_has_nonlocal_goto
= 1;
803 LABEL_REF_NONLOCAL_P (label_ref
) = 1;
805 /* Copy the rtl for the slots so that they won't be shared in
806 case the virtual stack vars register gets instantiated differently
807 in the parent than in the child. */
809 static_chain
= copy_to_reg (lookup_static_chain (label
));
811 /* Get addr of containing function's current nonlocal goto handler,
812 which will do any cleanups and then jump to the label. */
813 handler_slot
= copy_to_reg (replace_rtx (copy_rtx (handler_slot
),
814 virtual_stack_vars_rtx
,
817 /* Get addr of containing function's nonlocal save area. */
818 save_area
= p
->x_nonlocal_goto_stack_level
;
820 save_area
= replace_rtx (copy_rtx (save_area
),
821 virtual_stack_vars_rtx
, static_chain
);
823 #if HAVE_nonlocal_goto
824 if (HAVE_nonlocal_goto
)
825 emit_insn (gen_nonlocal_goto (static_chain
, handler_slot
,
826 save_area
, label_ref
));
830 /* Restore frame pointer for containing function.
831 This sets the actual hard register used for the frame pointer
832 to the location of the function's incoming static chain info.
833 The non-local goto handler will then adjust it to contain the
834 proper value and reload the argument pointer, if needed. */
835 emit_move_insn (hard_frame_pointer_rtx
, static_chain
);
836 emit_stack_restore (SAVE_NONLOCAL
, save_area
, NULL_RTX
);
838 /* USE of hard_frame_pointer_rtx added for consistency;
839 not clear if really needed. */
840 emit_insn (gen_rtx_USE (VOIDmode
, hard_frame_pointer_rtx
));
841 emit_insn (gen_rtx_USE (VOIDmode
, stack_pointer_rtx
));
842 emit_indirect_jump (handler_slot
);
845 /* Search backwards to the jump insn and mark it as a
847 for (insn
= get_last_insn (); insn
; insn
= PREV_INSN (insn
))
849 if (GET_CODE (insn
) == JUMP_INSN
)
851 REG_NOTES (insn
) = alloc_EXPR_LIST (REG_NON_LOCAL_GOTO
,
852 const0_rtx
, REG_NOTES (insn
));
855 else if (GET_CODE (insn
) == CALL_INSN
)
860 expand_goto_internal (label
, label_rtx (label
), NULL_RTX
);
863 /* Generate RTL code for a `goto' statement with target label BODY.
864 LABEL should be a LABEL_REF.
865 LAST_INSN, if non-0, is the rtx we should consider as the last
866 insn emitted (for the purposes of cleaning up a return). */
869 expand_goto_internal (body
, label
, last_insn
)
874 struct nesting
*block
;
877 if (GET_CODE (label
) != CODE_LABEL
)
880 /* If label has already been defined, we can tell now
881 whether and how we must alter the stack level. */
883 if (PREV_INSN (label
) != 0)
885 /* Find the innermost pending block that contains the label.
886 (Check containment by comparing insn-uids.)
887 Then restore the outermost stack level within that block,
888 and do cleanups of all blocks contained in it. */
889 for (block
= block_stack
; block
; block
= block
->next
)
891 if (INSN_UID (block
->data
.block
.first_insn
) < INSN_UID (label
))
893 if (block
->data
.block
.stack_level
!= 0)
894 stack_level
= block
->data
.block
.stack_level
;
895 /* Execute the cleanups for blocks we are exiting. */
896 if (block
->data
.block
.cleanups
!= 0)
898 expand_cleanups (block
->data
.block
.cleanups
, NULL_TREE
, 1, 1);
899 do_pending_stack_adjust ();
905 /* Ensure stack adjust isn't done by emit_jump, as this
906 would clobber the stack pointer. This one should be
907 deleted as dead by flow. */
908 clear_pending_stack_adjust ();
909 do_pending_stack_adjust ();
911 /* Don't do this adjust if it's to the end label and this function
912 is to return with a depressed stack pointer. */
913 if (label
== return_label
914 && (((TREE_CODE (TREE_TYPE (current_function_decl
))
916 && (TYPE_RETURNS_STACK_DEPRESSED
917 (TREE_TYPE (current_function_decl
))))))
920 emit_stack_restore (SAVE_BLOCK
, stack_level
, NULL_RTX
);
923 if (body
!= 0 && DECL_TOO_LATE (body
))
924 error ("jump to `%s' invalidly jumps into binding contour",
925 IDENTIFIER_POINTER (DECL_NAME (body
)));
927 /* Label not yet defined: may need to put this goto
928 on the fixup list. */
929 else if (! expand_fixup (body
, label
, last_insn
))
931 /* No fixup needed. Record that the label is the target
932 of at least one goto that has no fixup. */
934 TREE_ADDRESSABLE (body
) = 1;
940 /* Generate if necessary a fixup for a goto
941 whose target label in tree structure (if any) is TREE_LABEL
942 and whose target in rtl is RTL_LABEL.
944 If LAST_INSN is nonzero, we pretend that the jump appears
945 after insn LAST_INSN instead of at the current point in the insn stream.
947 The fixup will be used later to insert insns just before the goto.
948 Those insns will restore the stack level as appropriate for the
949 target label, and will (in the case of C++) also invoke any object
950 destructors which have to be invoked when we exit the scopes which
951 are exited by the goto.
953 Value is nonzero if a fixup is made. */
956 expand_fixup (tree_label
, rtl_label
, last_insn
)
961 struct nesting
*block
, *end_block
;
963 /* See if we can recognize which block the label will be output in.
964 This is possible in some very common cases.
965 If we succeed, set END_BLOCK to that block.
966 Otherwise, set it to 0. */
969 && (rtl_label
== cond_stack
->data
.cond
.endif_label
970 || rtl_label
== cond_stack
->data
.cond
.next_label
))
971 end_block
= cond_stack
;
972 /* If we are in a loop, recognize certain labels which
973 are likely targets. This reduces the number of fixups
974 we need to create. */
976 && (rtl_label
== loop_stack
->data
.loop
.start_label
977 || rtl_label
== loop_stack
->data
.loop
.end_label
978 || rtl_label
== loop_stack
->data
.loop
.continue_label
))
979 end_block
= loop_stack
;
983 /* Now set END_BLOCK to the binding level to which we will return. */
987 struct nesting
*next_block
= end_block
->all
;
990 /* First see if the END_BLOCK is inside the innermost binding level.
991 If so, then no cleanups or stack levels are relevant. */
992 while (next_block
&& next_block
!= block
)
993 next_block
= next_block
->all
;
998 /* Otherwise, set END_BLOCK to the innermost binding level
999 which is outside the relevant control-structure nesting. */
1000 next_block
= block_stack
->next
;
1001 for (block
= block_stack
; block
!= end_block
; block
= block
->all
)
1002 if (block
== next_block
)
1003 next_block
= next_block
->next
;
1004 end_block
= next_block
;
1007 /* Does any containing block have a stack level or cleanups?
1008 If not, no fixup is needed, and that is the normal case
1009 (the only case, for standard C). */
1010 for (block
= block_stack
; block
!= end_block
; block
= block
->next
)
1011 if (block
->data
.block
.stack_level
!= 0
1012 || block
->data
.block
.cleanups
!= 0)
1015 if (block
!= end_block
)
1017 /* Ok, a fixup is needed. Add a fixup to the list of such. */
1018 struct goto_fixup
*fixup
1019 = (struct goto_fixup
*) ggc_alloc (sizeof (struct goto_fixup
));
1020 /* In case an old stack level is restored, make sure that comes
1021 after any pending stack adjust. */
1022 /* ?? If the fixup isn't to come at the present position,
1023 doing the stack adjust here isn't useful. Doing it with our
1024 settings at that location isn't useful either. Let's hope
1027 do_pending_stack_adjust ();
1028 fixup
->target
= tree_label
;
1029 fixup
->target_rtl
= rtl_label
;
1031 /* Create a BLOCK node and a corresponding matched set of
1032 NOTE_INSN_BLOCK_BEG and NOTE_INSN_BLOCK_END notes at
1033 this point. The notes will encapsulate any and all fixup
1034 code which we might later insert at this point in the insn
1035 stream. Also, the BLOCK node will be the parent (i.e. the
1036 `SUPERBLOCK') of any other BLOCK nodes which we might create
1037 later on when we are expanding the fixup code.
1039 Note that optimization passes (including expand_end_loop)
1040 might move the *_BLOCK notes away, so we use a NOTE_INSN_DELETED
1041 as a placeholder. */
1044 register rtx original_before_jump
1045 = last_insn
? last_insn
: get_last_insn ();
1050 block
= make_node (BLOCK
);
1051 TREE_USED (block
) = 1;
1053 if (!cfun
->x_whole_function_mode_p
)
1054 insert_block (block
);
1058 = BLOCK_CHAIN (DECL_INITIAL (current_function_decl
));
1059 BLOCK_CHAIN (DECL_INITIAL (current_function_decl
))
1064 start
= emit_note (NULL
, NOTE_INSN_BLOCK_BEG
);
1065 if (cfun
->x_whole_function_mode_p
)
1066 NOTE_BLOCK (start
) = block
;
1067 fixup
->before_jump
= emit_note (NULL
, NOTE_INSN_DELETED
);
1068 end
= emit_note (NULL
, NOTE_INSN_BLOCK_END
);
1069 if (cfun
->x_whole_function_mode_p
)
1070 NOTE_BLOCK (end
) = block
;
1071 fixup
->context
= block
;
1073 emit_insns_after (start
, original_before_jump
);
1076 fixup
->block_start_count
= current_block_start_count
;
1077 fixup
->stack_level
= 0;
1078 fixup
->cleanup_list_list
1079 = ((block
->data
.block
.outer_cleanups
1080 || block
->data
.block
.cleanups
)
1081 ? tree_cons (NULL_TREE
, block
->data
.block
.cleanups
,
1082 block
->data
.block
.outer_cleanups
)
1084 fixup
->next
= goto_fixup_chain
;
1085 goto_fixup_chain
= fixup
;
1091 /* Expand any needed fixups in the outputmost binding level of the
1092 function. FIRST_INSN is the first insn in the function. */
1095 expand_fixups (first_insn
)
1098 fixup_gotos (NULL
, NULL_RTX
, NULL_TREE
, first_insn
, 0);
1101 /* When exiting a binding contour, process all pending gotos requiring fixups.
1102 THISBLOCK is the structure that describes the block being exited.
1103 STACK_LEVEL is the rtx for the stack level to restore exiting this contour.
1104 CLEANUP_LIST is a list of expressions to evaluate on exiting this contour.
1105 FIRST_INSN is the insn that began this contour.
1107 Gotos that jump out of this contour must restore the
1108 stack level and do the cleanups before actually jumping.
1110 DONT_JUMP_IN nonzero means report error there is a jump into this
1111 contour from before the beginning of the contour.
1112 This is also done if STACK_LEVEL is nonzero. */
1115 fixup_gotos (thisblock
, stack_level
, cleanup_list
, first_insn
, dont_jump_in
)
1116 struct nesting
*thisblock
;
1122 register struct goto_fixup
*f
, *prev
;
1124 /* F is the fixup we are considering; PREV is the previous one. */
1125 /* We run this loop in two passes so that cleanups of exited blocks
1126 are run first, and blocks that are exited are marked so
1129 for (prev
= 0, f
= goto_fixup_chain
; f
; prev
= f
, f
= f
->next
)
1131 /* Test for a fixup that is inactive because it is already handled. */
1132 if (f
->before_jump
== 0)
1134 /* Delete inactive fixup from the chain, if that is easy to do. */
1136 prev
->next
= f
->next
;
1138 /* Has this fixup's target label been defined?
1139 If so, we can finalize it. */
1140 else if (PREV_INSN (f
->target_rtl
) != 0)
1142 register rtx cleanup_insns
;
1144 /* If this fixup jumped into this contour from before the beginning
1145 of this contour, report an error. This code used to use
1146 the first non-label insn after f->target_rtl, but that's
1147 wrong since such can be added, by things like put_var_into_stack
1148 and have INSN_UIDs that are out of the range of the block. */
1149 /* ??? Bug: this does not detect jumping in through intermediate
1150 blocks that have stack levels or cleanups.
1151 It detects only a problem with the innermost block
1152 around the label. */
1154 && (dont_jump_in
|| stack_level
|| cleanup_list
)
1155 && INSN_UID (first_insn
) < INSN_UID (f
->target_rtl
)
1156 && INSN_UID (first_insn
) > INSN_UID (f
->before_jump
)
1157 && ! DECL_ERROR_ISSUED (f
->target
))
1159 error_with_decl (f
->target
,
1160 "label `%s' used before containing binding contour");
1161 /* Prevent multiple errors for one label. */
1162 DECL_ERROR_ISSUED (f
->target
) = 1;
1165 /* We will expand the cleanups into a sequence of their own and
1166 then later on we will attach this new sequence to the insn
1167 stream just ahead of the actual jump insn. */
1171 /* Temporarily restore the lexical context where we will
1172 logically be inserting the fixup code. We do this for the
1173 sake of getting the debugging information right. */
1176 set_block (f
->context
);
1178 /* Expand the cleanups for blocks this jump exits. */
1179 if (f
->cleanup_list_list
)
1182 for (lists
= f
->cleanup_list_list
; lists
; lists
= TREE_CHAIN (lists
))
1183 /* Marked elements correspond to blocks that have been closed.
1184 Do their cleanups. */
1185 if (TREE_ADDRESSABLE (lists
)
1186 && TREE_VALUE (lists
) != 0)
1188 expand_cleanups (TREE_VALUE (lists
), NULL_TREE
, 1, 1);
1189 /* Pop any pushes done in the cleanups,
1190 in case function is about to return. */
1191 do_pending_stack_adjust ();
1195 /* Restore stack level for the biggest contour that this
1196 jump jumps out of. */
1198 && ! (f
->target_rtl
== return_label
1199 && ((TREE_CODE (TREE_TYPE (current_function_decl
))
1201 && (TYPE_RETURNS_STACK_DEPRESSED
1202 (TREE_TYPE (current_function_decl
))))))
1203 emit_stack_restore (SAVE_BLOCK
, f
->stack_level
, f
->before_jump
);
1205 /* Finish up the sequence containing the insns which implement the
1206 necessary cleanups, and then attach that whole sequence to the
1207 insn stream just ahead of the actual jump insn. Attaching it
1208 at that point insures that any cleanups which are in fact
1209 implicit C++ object destructions (which must be executed upon
1210 leaving the block) appear (to the debugger) to be taking place
1211 in an area of the generated code where the object(s) being
1212 destructed are still "in scope". */
1214 cleanup_insns
= get_insns ();
1218 emit_insns_after (cleanup_insns
, f
->before_jump
);
1224 /* For any still-undefined labels, do the cleanups for this block now.
1225 We must do this now since items in the cleanup list may go out
1226 of scope when the block ends. */
1227 for (prev
= 0, f
= goto_fixup_chain
; f
; prev
= f
, f
= f
->next
)
1228 if (f
->before_jump
!= 0
1229 && PREV_INSN (f
->target_rtl
) == 0
1230 /* Label has still not appeared. If we are exiting a block with
1231 a stack level to restore, that started before the fixup,
1232 mark this stack level as needing restoration
1233 when the fixup is later finalized. */
1235 /* Note: if THISBLOCK == 0 and we have a label that hasn't appeared, it
1236 means the label is undefined. That's erroneous, but possible. */
1237 && (thisblock
->data
.block
.block_start_count
1238 <= f
->block_start_count
))
1240 tree lists
= f
->cleanup_list_list
;
1243 for (; lists
; lists
= TREE_CHAIN (lists
))
1244 /* If the following elt. corresponds to our containing block
1245 then the elt. must be for this block. */
1246 if (TREE_CHAIN (lists
) == thisblock
->data
.block
.outer_cleanups
)
1250 set_block (f
->context
);
1251 expand_cleanups (TREE_VALUE (lists
), NULL_TREE
, 1, 1);
1252 do_pending_stack_adjust ();
1253 cleanup_insns
= get_insns ();
1256 if (cleanup_insns
!= 0)
1258 = emit_insns_after (cleanup_insns
, f
->before_jump
);
1260 f
->cleanup_list_list
= TREE_CHAIN (lists
);
1264 f
->stack_level
= stack_level
;
1268 /* Return the number of times character C occurs in string S. */
1270 n_occurrences (c
, s
)
1280 /* Generate RTL for an asm statement (explicit assembler code).
1281 BODY is a STRING_CST node containing the assembler code text,
1282 or an ADDR_EXPR containing a STRING_CST. */
1288 if (current_function_check_memory_usage
)
1290 error ("`asm' cannot be used in function where memory usage is checked");
1294 if (TREE_CODE (body
) == ADDR_EXPR
)
1295 body
= TREE_OPERAND (body
, 0);
1297 emit_insn (gen_rtx_ASM_INPUT (VOIDmode
,
1298 TREE_STRING_POINTER (body
)));
1302 /* Parse the output constraint pointed to by *CONSTRAINT_P. It is the
1303 OPERAND_NUMth output operand, indexed from zero. There are NINPUTS
1304 inputs and NOUTPUTS outputs to this extended-asm. Upon return,
1305 *ALLOWS_MEM will be TRUE iff the constraint allows the use of a
1306 memory operand. Similarly, *ALLOWS_REG will be TRUE iff the
1307 constraint allows the use of a register operand. And, *IS_INOUT
1308 will be true if the operand is read-write, i.e., if it is used as
1309 an input as well as an output. If *CONSTRAINT_P is not in
1310 canonical form, it will be made canonical. (Note that `+' will be
1311 rpelaced with `=' as part of this process.)
1313 Returns TRUE if all went well; FALSE if an error occurred. */
1316 parse_output_constraint (constraint_p
,
1323 const char **constraint_p
;
1331 const char *constraint
= *constraint_p
;
1334 /* Assume the constraint doesn't allow the use of either a register
1336 *allows_mem
= false;
1337 *allows_reg
= false;
1339 /* Allow the `=' or `+' to not be at the beginning of the string,
1340 since it wasn't explicitly documented that way, and there is a
1341 large body of code that puts it last. Swap the character to
1342 the front, so as not to uglify any place else. */
1343 p
= strchr (constraint
, '=');
1345 p
= strchr (constraint
, '+');
1347 /* If the string doesn't contain an `=', issue an error
1351 error ("output operand constraint lacks `='");
1355 /* If the constraint begins with `+', then the operand is both read
1356 from and written to. */
1357 *is_inout
= (*p
== '+');
1359 /* Make sure we can specify the matching operand. */
1360 if (*is_inout
&& operand_num
> 9)
1362 error ("output operand constraint %d contains `+'",
1367 /* Canonicalize the output constraint so that it begins with `='. */
1368 if (p
!= constraint
|| is_inout
)
1371 size_t c_len
= strlen (constraint
);
1373 if (p
!= constraint
)
1374 warning ("output constraint `%c' for operand %d is not at the beginning",
1377 /* Make a copy of the constraint. */
1378 buf
= alloca (c_len
+ 1);
1379 strcpy (buf
, constraint
);
1380 /* Swap the first character and the `=' or `+'. */
1381 buf
[p
- constraint
] = buf
[0];
1382 /* Make sure the first character is an `='. (Until we do this,
1383 it might be a `+'.) */
1385 /* Replace the constraint with the canonicalized string. */
1386 *constraint_p
= ggc_alloc_string (buf
, c_len
);
1387 constraint
= *constraint_p
;
1390 /* Loop through the constraint string. */
1391 for (p
= constraint
+ 1; *p
; ++p
)
1396 error ("operand constraint contains '+' or '=' at illegal position.");
1400 if (operand_num
+ 1 == ninputs
+ noutputs
)
1402 error ("`%%' constraint used with last operand");
1407 case 'V': case 'm': case 'o':
1411 case '?': case '!': case '*': case '&': case '#':
1412 case 'E': case 'F': case 'G': case 'H':
1413 case 's': case 'i': case 'n':
1414 case 'I': case 'J': case 'K': case 'L': case 'M':
1415 case 'N': case 'O': case 'P': case ',':
1418 case '0': case '1': case '2': case '3': case '4':
1419 case '5': case '6': case '7': case '8': case '9':
1420 error ("matching constraint not valid in output operand");
1424 /* ??? Before flow, auto inc/dec insns are not supposed to exist,
1425 excepting those that expand_call created. So match memory
1442 if (REG_CLASS_FROM_LETTER (*p
) != NO_REGS
)
1444 #ifdef EXTRA_CONSTRAINT
1447 /* Otherwise we can't assume anything about the nature of
1448 the constraint except that it isn't purely registers.
1449 Treat it like "g" and hope for the best. */
1460 /* Generate RTL for an asm statement with arguments.
1461 STRING is the instruction template.
1462 OUTPUTS is a list of output arguments (lvalues); INPUTS a list of inputs.
1463 Each output or input has an expression in the TREE_VALUE and
1464 a constraint-string in the TREE_PURPOSE.
1465 CLOBBERS is a list of STRING_CST nodes each naming a hard register
1466 that is clobbered by this insn.
1468 Not all kinds of lvalue that may appear in OUTPUTS can be stored directly.
1469 Some elements of OUTPUTS may be replaced with trees representing temporary
1470 values. The caller should copy those temporary values to the originally
1473 VOL nonzero means the insn is volatile; don't optimize it. */
1476 expand_asm_operands (string
, outputs
, inputs
, clobbers
, vol
, filename
, line
)
1477 tree string
, outputs
, inputs
, clobbers
;
1479 const char *filename
;
1482 rtvec argvec
, constraints
;
1484 int ninputs
= list_length (inputs
);
1485 int noutputs
= list_length (outputs
);
1490 /* Vector of RTX's of evaluated output operands. */
1491 rtx
*output_rtx
= (rtx
*) alloca (noutputs
* sizeof (rtx
));
1492 int *inout_opnum
= (int *) alloca (noutputs
* sizeof (int));
1493 rtx
*real_output_rtx
= (rtx
*) alloca (noutputs
* sizeof (rtx
));
1494 enum machine_mode
*inout_mode
1495 = (enum machine_mode
*) alloca (noutputs
* sizeof (enum machine_mode
));
1496 const char **output_constraints
1497 = alloca (noutputs
* sizeof (const char *));
1498 /* The insn we have emitted. */
1500 int old_generating_concat_p
= generating_concat_p
;
1502 /* An ASM with no outputs needs to be treated as volatile, for now. */
1506 if (current_function_check_memory_usage
)
1508 error ("`asm' cannot be used with `-fcheck-memory-usage'");
1512 #ifdef MD_ASM_CLOBBERS
1513 /* Sometimes we wish to automatically clobber registers across an asm.
1514 Case in point is when the i386 backend moved from cc0 to a hard reg --
1515 maintaining source-level compatability means automatically clobbering
1516 the flags register. */
1517 MD_ASM_CLOBBERS (clobbers
);
1520 if (current_function_check_memory_usage
)
1522 error ("`asm' cannot be used in function where memory usage is checked");
1526 /* Count the number of meaningful clobbered registers, ignoring what
1527 we would ignore later. */
1529 for (tail
= clobbers
; tail
; tail
= TREE_CHAIN (tail
))
1531 const char *regname
= TREE_STRING_POINTER (TREE_VALUE (tail
));
1533 i
= decode_reg_name (regname
);
1534 if (i
>= 0 || i
== -4)
1537 error ("unknown register name `%s' in `asm'", regname
);
1542 /* Check that the number of alternatives is constant across all
1544 if (outputs
|| inputs
)
1546 tree tmp
= TREE_PURPOSE (outputs
? outputs
: inputs
);
1547 int nalternatives
= n_occurrences (',', TREE_STRING_POINTER (tmp
));
1550 if (nalternatives
+ 1 > MAX_RECOG_ALTERNATIVES
)
1552 error ("too many alternatives in `asm'");
1559 const char *constraint
= TREE_STRING_POINTER (TREE_PURPOSE (tmp
));
1561 if (n_occurrences (',', constraint
) != nalternatives
)
1563 error ("operand constraints for `asm' differ in number of alternatives");
1567 if (TREE_CHAIN (tmp
))
1568 tmp
= TREE_CHAIN (tmp
);
1570 tmp
= next
, next
= 0;
1574 for (i
= 0, tail
= outputs
; tail
; tail
= TREE_CHAIN (tail
), i
++)
1576 tree val
= TREE_VALUE (tail
);
1577 tree type
= TREE_TYPE (val
);
1578 const char *constraint
;
1583 /* If there's an erroneous arg, emit no insn. */
1584 if (type
== error_mark_node
)
1587 /* Make sure constraint has `=' and does not have `+'. Also, see
1588 if it allows any register. Be liberal on the latter test, since
1589 the worst that happens if we get it wrong is we issue an error
1592 constraint
= TREE_STRING_POINTER (TREE_PURPOSE (tail
));
1593 output_constraints
[i
] = constraint
;
1595 /* Try to parse the output constraint. If that fails, there's
1596 no point in going further. */
1597 if (!parse_output_constraint (&output_constraints
[i
],
1606 /* If an output operand is not a decl or indirect ref and our constraint
1607 allows a register, make a temporary to act as an intermediate.
1608 Make the asm insn write into that, then our caller will copy it to
1609 the real output operand. Likewise for promoted variables. */
1611 generating_concat_p
= 0;
1613 real_output_rtx
[i
] = NULL_RTX
;
1614 if ((TREE_CODE (val
) == INDIRECT_REF
1617 && (allows_mem
|| GET_CODE (DECL_RTL (val
)) == REG
)
1618 && ! (GET_CODE (DECL_RTL (val
)) == REG
1619 && GET_MODE (DECL_RTL (val
)) != TYPE_MODE (type
)))
1624 mark_addressable (TREE_VALUE (tail
));
1627 = expand_expr (TREE_VALUE (tail
), NULL_RTX
, VOIDmode
,
1628 EXPAND_MEMORY_USE_WO
);
1630 if (! allows_reg
&& GET_CODE (output_rtx
[i
]) != MEM
)
1631 error ("output number %d not directly addressable", i
);
1632 if ((! allows_mem
&& GET_CODE (output_rtx
[i
]) == MEM
)
1633 || GET_CODE (output_rtx
[i
]) == CONCAT
)
1635 real_output_rtx
[i
] = protect_from_queue (output_rtx
[i
], 1);
1636 output_rtx
[i
] = gen_reg_rtx (GET_MODE (output_rtx
[i
]));
1638 emit_move_insn (output_rtx
[i
], real_output_rtx
[i
]);
1643 output_rtx
[i
] = assign_temp (type
, 0, 0, 1);
1644 TREE_VALUE (tail
) = make_tree (type
, output_rtx
[i
]);
1647 generating_concat_p
= old_generating_concat_p
;
1651 inout_mode
[ninout
] = TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
)));
1652 inout_opnum
[ninout
++] = i
;
1657 if (ninputs
+ noutputs
> MAX_RECOG_OPERANDS
)
1659 error ("more than %d operands in `asm'", MAX_RECOG_OPERANDS
);
1663 /* Make vectors for the expression-rtx and constraint strings. */
1665 argvec
= rtvec_alloc (ninputs
);
1666 constraints
= rtvec_alloc (ninputs
);
1668 body
= gen_rtx_ASM_OPERANDS ((noutputs
== 0 ? VOIDmode
1669 : GET_MODE (output_rtx
[0])),
1670 TREE_STRING_POINTER (string
),
1671 empty_string
, 0, argvec
, constraints
,
1674 MEM_VOLATILE_P (body
) = vol
;
1676 /* Eval the inputs and put them into ARGVEC.
1677 Put their constraints into ASM_INPUTs and store in CONSTRAINTS. */
1680 for (tail
= inputs
; tail
; tail
= TREE_CHAIN (tail
))
1683 int allows_reg
= 0, allows_mem
= 0;
1684 const char *constraint
, *orig_constraint
;
1688 /* If there's an erroneous arg, emit no insn,
1689 because the ASM_INPUT would get VOIDmode
1690 and that could cause a crash in reload. */
1691 if (TREE_TYPE (TREE_VALUE (tail
)) == error_mark_node
)
1694 /* ??? Can this happen, and does the error message make any sense? */
1695 if (TREE_PURPOSE (tail
) == NULL_TREE
)
1697 error ("hard register `%s' listed as input operand to `asm'",
1698 TREE_STRING_POINTER (TREE_VALUE (tail
)) );
1702 constraint
= TREE_STRING_POINTER (TREE_PURPOSE (tail
));
1703 c_len
= strlen (constraint
);
1704 orig_constraint
= constraint
;
1706 /* Make sure constraint has neither `=', `+', nor '&'. */
1708 for (j
= 0; j
< c_len
; j
++)
1709 switch (constraint
[j
])
1711 case '+': case '=': case '&':
1712 if (constraint
== orig_constraint
)
1714 error ("input operand constraint contains `%c'",
1721 if (constraint
== orig_constraint
1722 && i
+ 1 == ninputs
- ninout
)
1724 error ("`%%' constraint used with last operand");
1729 case 'V': case 'm': case 'o':
1734 case '?': case '!': case '*': case '#':
1735 case 'E': case 'F': case 'G': case 'H':
1736 case 's': case 'i': case 'n':
1737 case 'I': case 'J': case 'K': case 'L': case 'M':
1738 case 'N': case 'O': case 'P': case ',':
1741 /* Whether or not a numeric constraint allows a register is
1742 decided by the matching constraint, and so there is no need
1743 to do anything special with them. We must handle them in
1744 the default case, so that we don't unnecessarily force
1745 operands to memory. */
1746 case '0': case '1': case '2': case '3': case '4':
1747 case '5': case '6': case '7': case '8': case '9':
1748 if (constraint
[j
] >= '0' + noutputs
)
1751 ("matching constraint references invalid operand number");
1755 /* Try and find the real constraint for this dup. */
1756 if ((j
== 0 && c_len
== 1)
1757 || (j
== 1 && c_len
== 2 && constraint
[0] == '%'))
1761 for (j
= constraint
[j
] - '0'; j
> 0; --j
)
1764 constraint
= TREE_STRING_POINTER (TREE_PURPOSE (o
));
1765 c_len
= strlen (constraint
);
1782 if (! ISALPHA (constraint
[j
]))
1784 error ("invalid punctuation `%c' in constraint",
1788 if (REG_CLASS_FROM_LETTER (constraint
[j
]) != NO_REGS
)
1790 #ifdef EXTRA_CONSTRAINT
1793 /* Otherwise we can't assume anything about the nature of
1794 the constraint except that it isn't purely registers.
1795 Treat it like "g" and hope for the best. */
1803 if (! allows_reg
&& allows_mem
)
1804 mark_addressable (TREE_VALUE (tail
));
1806 op
= expand_expr (TREE_VALUE (tail
), NULL_RTX
, VOIDmode
, 0);
1808 /* Never pass a CONCAT to an ASM. */
1809 generating_concat_p
= 0;
1810 if (GET_CODE (op
) == CONCAT
)
1811 op
= force_reg (GET_MODE (op
), op
);
1813 if (asm_operand_ok (op
, constraint
) <= 0)
1816 op
= force_reg (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
))), op
);
1817 else if (!allows_mem
)
1818 warning ("asm operand %d probably doesn't match constraints", i
);
1819 else if (CONSTANT_P (op
))
1820 op
= force_const_mem (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
))),
1822 else if (GET_CODE (op
) == REG
1823 || GET_CODE (op
) == SUBREG
1824 || GET_CODE (op
) == ADDRESSOF
1825 || GET_CODE (op
) == CONCAT
)
1827 tree type
= TREE_TYPE (TREE_VALUE (tail
));
1828 tree qual_type
= build_qualified_type (type
,
1830 | TYPE_QUAL_CONST
));
1831 rtx memloc
= assign_temp (qual_type
, 1, 1, 1);
1833 emit_move_insn (memloc
, op
);
1837 else if (GET_CODE (op
) == MEM
&& MEM_VOLATILE_P (op
))
1838 /* We won't recognize volatile memory as available a
1839 memory_operand at this point. Ignore it. */
1841 else if (queued_subexp_p (op
))
1844 /* ??? Leave this only until we have experience with what
1845 happens in combine and elsewhere when constraints are
1847 warning ("asm operand %d probably doesn't match constraints", i
);
1849 generating_concat_p
= old_generating_concat_p
;
1850 ASM_OPERANDS_INPUT (body
, i
) = op
;
1852 ASM_OPERANDS_INPUT_CONSTRAINT_EXP (body
, i
)
1853 = gen_rtx_ASM_INPUT (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
))),
1858 /* Protect all the operands from the queue now that they have all been
1861 generating_concat_p
= 0;
1863 for (i
= 0; i
< ninputs
- ninout
; i
++)
1864 ASM_OPERANDS_INPUT (body
, i
)
1865 = protect_from_queue (ASM_OPERANDS_INPUT (body
, i
), 0);
1867 for (i
= 0; i
< noutputs
; i
++)
1868 output_rtx
[i
] = protect_from_queue (output_rtx
[i
], 1);
1870 /* For in-out operands, copy output rtx to input rtx. */
1871 for (i
= 0; i
< ninout
; i
++)
1873 int j
= inout_opnum
[i
];
1875 ASM_OPERANDS_INPUT (body
, ninputs
- ninout
+ i
)
1877 ASM_OPERANDS_INPUT_CONSTRAINT_EXP (body
, ninputs
- ninout
+ i
)
1878 = gen_rtx_ASM_INPUT (inout_mode
[i
], digit_string (j
));
1881 generating_concat_p
= old_generating_concat_p
;
1883 /* Now, for each output, construct an rtx
1884 (set OUTPUT (asm_operands INSN OUTPUTNUMBER OUTPUTCONSTRAINT
1885 ARGVEC CONSTRAINTS))
1886 If there is more than one, put them inside a PARALLEL. */
1888 if (noutputs
== 1 && nclobbers
== 0)
1890 ASM_OPERANDS_OUTPUT_CONSTRAINT (body
)
1891 = output_constraints
[0];
1892 insn
= emit_insn (gen_rtx_SET (VOIDmode
, output_rtx
[0], body
));
1895 else if (noutputs
== 0 && nclobbers
== 0)
1897 /* No output operands: put in a raw ASM_OPERANDS rtx. */
1898 insn
= emit_insn (body
);
1909 body
= gen_rtx_PARALLEL (VOIDmode
, rtvec_alloc (num
+ nclobbers
));
1911 /* For each output operand, store a SET. */
1912 for (i
= 0, tail
= outputs
; tail
; tail
= TREE_CHAIN (tail
), i
++)
1914 XVECEXP (body
, 0, i
)
1915 = gen_rtx_SET (VOIDmode
,
1917 gen_rtx_ASM_OPERANDS
1918 (GET_MODE (output_rtx
[i
]),
1919 TREE_STRING_POINTER (string
),
1920 output_constraints
[i
],
1921 i
, argvec
, constraints
,
1924 MEM_VOLATILE_P (SET_SRC (XVECEXP (body
, 0, i
))) = vol
;
1927 /* If there are no outputs (but there are some clobbers)
1928 store the bare ASM_OPERANDS into the PARALLEL. */
1931 XVECEXP (body
, 0, i
++) = obody
;
1933 /* Store (clobber REG) for each clobbered register specified. */
1935 for (tail
= clobbers
; tail
; tail
= TREE_CHAIN (tail
))
1937 const char *regname
= TREE_STRING_POINTER (TREE_VALUE (tail
));
1938 int j
= decode_reg_name (regname
);
1942 if (j
== -3) /* `cc', which is not a register */
1945 if (j
== -4) /* `memory', don't cache memory across asm */
1947 XVECEXP (body
, 0, i
++)
1948 = gen_rtx_CLOBBER (VOIDmode
,
1951 gen_rtx_SCRATCH (VOIDmode
)));
1955 /* Ignore unknown register, error already signaled. */
1959 /* Use QImode since that's guaranteed to clobber just one reg. */
1960 XVECEXP (body
, 0, i
++)
1961 = gen_rtx_CLOBBER (VOIDmode
, gen_rtx_REG (QImode
, j
));
1964 insn
= emit_insn (body
);
1967 /* For any outputs that needed reloading into registers, spill them
1968 back to where they belong. */
1969 for (i
= 0; i
< noutputs
; ++i
)
1970 if (real_output_rtx
[i
])
1971 emit_move_insn (real_output_rtx
[i
], output_rtx
[i
]);
1976 /* Generate RTL to evaluate the expression EXP
1977 and remember it in case this is the VALUE in a ({... VALUE; }) constr. */
1980 expand_expr_stmt (exp
)
1983 /* If -W, warn about statements with no side effects,
1984 except for an explicit cast to void (e.g. for assert()), and
1985 except inside a ({...}) where they may be useful. */
1986 if (expr_stmts_for_value
== 0 && exp
!= error_mark_node
)
1988 if (! TREE_SIDE_EFFECTS (exp
))
1990 if ((extra_warnings
|| warn_unused_value
)
1991 && !(TREE_CODE (exp
) == CONVERT_EXPR
1992 && VOID_TYPE_P (TREE_TYPE (exp
))))
1993 warning_with_file_and_line (emit_filename
, emit_lineno
,
1994 "statement with no effect");
1996 else if (warn_unused_value
)
1997 warn_if_unused_value (exp
);
2000 /* If EXP is of function type and we are expanding statements for
2001 value, convert it to pointer-to-function. */
2002 if (expr_stmts_for_value
&& TREE_CODE (TREE_TYPE (exp
)) == FUNCTION_TYPE
)
2003 exp
= build1 (ADDR_EXPR
, build_pointer_type (TREE_TYPE (exp
)), exp
);
2005 /* The call to `expand_expr' could cause last_expr_type and
2006 last_expr_value to get reset. Therefore, we set last_expr_value
2007 and last_expr_type *after* calling expand_expr. */
2008 last_expr_value
= expand_expr (exp
,
2009 (expr_stmts_for_value
2010 ? NULL_RTX
: const0_rtx
),
2012 last_expr_type
= TREE_TYPE (exp
);
2014 /* If all we do is reference a volatile value in memory,
2015 copy it to a register to be sure it is actually touched. */
2016 if (last_expr_value
!= 0 && GET_CODE (last_expr_value
) == MEM
2017 && TREE_THIS_VOLATILE (exp
))
2019 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
)
2021 else if (TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
)
2022 copy_to_reg (last_expr_value
);
2025 rtx lab
= gen_label_rtx ();
2027 /* Compare the value with itself to reference it. */
2028 emit_cmp_and_jump_insns (last_expr_value
, last_expr_value
, EQ
,
2029 expand_expr (TYPE_SIZE (last_expr_type
),
2030 NULL_RTX
, VOIDmode
, 0),
2032 TYPE_ALIGN (last_expr_type
) / BITS_PER_UNIT
,
2038 /* If this expression is part of a ({...}) and is in memory, we may have
2039 to preserve temporaries. */
2040 preserve_temp_slots (last_expr_value
);
2042 /* Free any temporaries used to evaluate this expression. Any temporary
2043 used as a result of this expression will already have been preserved
2050 /* Warn if EXP contains any computations whose results are not used.
2051 Return 1 if a warning is printed; 0 otherwise. */
2054 warn_if_unused_value (exp
)
2057 if (TREE_USED (exp
))
2060 /* Don't warn about void constructs. This includes casting to void,
2061 void function calls, and statement expressions with a final cast
2063 if (VOID_TYPE_P (TREE_TYPE (exp
)))
2066 /* If this is an expression with side effects, don't warn. */
2067 if (TREE_SIDE_EFFECTS (exp
))
2070 switch (TREE_CODE (exp
))
2072 case PREINCREMENT_EXPR
:
2073 case POSTINCREMENT_EXPR
:
2074 case PREDECREMENT_EXPR
:
2075 case POSTDECREMENT_EXPR
:
2080 case METHOD_CALL_EXPR
:
2082 case TRY_CATCH_EXPR
:
2083 case WITH_CLEANUP_EXPR
:
2088 /* For a binding, warn if no side effect within it. */
2089 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2092 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2094 case TRUTH_ORIF_EXPR
:
2095 case TRUTH_ANDIF_EXPR
:
2096 /* In && or ||, warn if 2nd operand has no side effect. */
2097 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2100 if (TREE_NO_UNUSED_WARNING (exp
))
2102 if (warn_if_unused_value (TREE_OPERAND (exp
, 0)))
2104 /* Let people do `(foo (), 0)' without a warning. */
2105 if (TREE_CONSTANT (TREE_OPERAND (exp
, 1)))
2107 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2111 case NON_LVALUE_EXPR
:
2112 /* Don't warn about conversions not explicit in the user's program. */
2113 if (TREE_NO_UNUSED_WARNING (exp
))
2115 /* Assignment to a cast usually results in a cast of a modify.
2116 Don't complain about that. There can be an arbitrary number of
2117 casts before the modify, so we must loop until we find the first
2118 non-cast expression and then test to see if that is a modify. */
2120 tree tem
= TREE_OPERAND (exp
, 0);
2122 while (TREE_CODE (tem
) == CONVERT_EXPR
|| TREE_CODE (tem
) == NOP_EXPR
)
2123 tem
= TREE_OPERAND (tem
, 0);
2125 if (TREE_CODE (tem
) == MODIFY_EXPR
|| TREE_CODE (tem
) == INIT_EXPR
2126 || TREE_CODE (tem
) == CALL_EXPR
)
2132 /* Don't warn about automatic dereferencing of references, since
2133 the user cannot control it. */
2134 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (exp
, 0))) == REFERENCE_TYPE
)
2135 return warn_if_unused_value (TREE_OPERAND (exp
, 0));
2139 /* Referencing a volatile value is a side effect, so don't warn. */
2141 || TREE_CODE_CLASS (TREE_CODE (exp
)) == 'r')
2142 && TREE_THIS_VOLATILE (exp
))
2145 /* If this is an expression which has no operands, there is no value
2146 to be unused. There are no such language-independent codes,
2147 but front ends may define such. */
2148 if (TREE_CODE_CLASS (TREE_CODE (exp
)) == 'e'
2149 && TREE_CODE_LENGTH (TREE_CODE (exp
)) == 0)
2153 warning_with_file_and_line (emit_filename
, emit_lineno
,
2154 "value computed is not used");
2159 /* Clear out the memory of the last expression evaluated. */
2167 /* Begin a statement which will return a value.
2168 Return the RTL_EXPR for this statement expr.
2169 The caller must save that value and pass it to expand_end_stmt_expr. */
2172 expand_start_stmt_expr ()
2176 /* Make the RTL_EXPR node temporary, not momentary,
2177 so that rtl_expr_chain doesn't become garbage. */
2178 t
= make_node (RTL_EXPR
);
2179 do_pending_stack_adjust ();
2180 start_sequence_for_rtl_expr (t
);
2182 expr_stmts_for_value
++;
2186 /* Restore the previous state at the end of a statement that returns a value.
2187 Returns a tree node representing the statement's value and the
2188 insns to compute the value.
2190 The nodes of that expression have been freed by now, so we cannot use them.
2191 But we don't want to do that anyway; the expression has already been
2192 evaluated and now we just want to use the value. So generate a RTL_EXPR
2193 with the proper type and RTL value.
2195 If the last substatement was not an expression,
2196 return something with type `void'. */
2199 expand_end_stmt_expr (t
)
2204 if (last_expr_type
== 0)
2206 last_expr_type
= void_type_node
;
2207 last_expr_value
= const0_rtx
;
2209 else if (last_expr_value
== 0)
2210 /* There are some cases where this can happen, such as when the
2211 statement is void type. */
2212 last_expr_value
= const0_rtx
;
2213 else if (GET_CODE (last_expr_value
) != REG
&& ! CONSTANT_P (last_expr_value
))
2214 /* Remove any possible QUEUED. */
2215 last_expr_value
= protect_from_queue (last_expr_value
, 0);
2219 TREE_TYPE (t
) = last_expr_type
;
2220 RTL_EXPR_RTL (t
) = last_expr_value
;
2221 RTL_EXPR_SEQUENCE (t
) = get_insns ();
2223 rtl_expr_chain
= tree_cons (NULL_TREE
, t
, rtl_expr_chain
);
2227 /* Don't consider deleting this expr or containing exprs at tree level. */
2228 TREE_SIDE_EFFECTS (t
) = 1;
2229 /* Propagate volatility of the actual RTL expr. */
2230 TREE_THIS_VOLATILE (t
) = volatile_refs_p (last_expr_value
);
2233 expr_stmts_for_value
--;
2238 /* Generate RTL for the start of an if-then. COND is the expression
2239 whose truth should be tested.
2241 If EXITFLAG is nonzero, this conditional is visible to
2242 `exit_something'. */
2245 expand_start_cond (cond
, exitflag
)
2249 struct nesting
*thiscond
= ALLOC_NESTING ();
2251 /* Make an entry on cond_stack for the cond we are entering. */
2253 thiscond
->next
= cond_stack
;
2254 thiscond
->all
= nesting_stack
;
2255 thiscond
->depth
= ++nesting_depth
;
2256 thiscond
->data
.cond
.next_label
= gen_label_rtx ();
2257 /* Before we encounter an `else', we don't need a separate exit label
2258 unless there are supposed to be exit statements
2259 to exit this conditional. */
2260 thiscond
->exit_label
= exitflag
? gen_label_rtx () : 0;
2261 thiscond
->data
.cond
.endif_label
= thiscond
->exit_label
;
2262 cond_stack
= thiscond
;
2263 nesting_stack
= thiscond
;
2265 do_jump (cond
, thiscond
->data
.cond
.next_label
, NULL_RTX
);
2268 /* Generate RTL between then-clause and the elseif-clause
2269 of an if-then-elseif-.... */
2272 expand_start_elseif (cond
)
2275 if (cond_stack
->data
.cond
.endif_label
== 0)
2276 cond_stack
->data
.cond
.endif_label
= gen_label_rtx ();
2277 emit_jump (cond_stack
->data
.cond
.endif_label
);
2278 emit_label (cond_stack
->data
.cond
.next_label
);
2279 cond_stack
->data
.cond
.next_label
= gen_label_rtx ();
2280 do_jump (cond
, cond_stack
->data
.cond
.next_label
, NULL_RTX
);
2283 /* Generate RTL between the then-clause and the else-clause
2284 of an if-then-else. */
2287 expand_start_else ()
2289 if (cond_stack
->data
.cond
.endif_label
== 0)
2290 cond_stack
->data
.cond
.endif_label
= gen_label_rtx ();
2292 emit_jump (cond_stack
->data
.cond
.endif_label
);
2293 emit_label (cond_stack
->data
.cond
.next_label
);
2294 cond_stack
->data
.cond
.next_label
= 0; /* No more _else or _elseif calls. */
2297 /* After calling expand_start_else, turn this "else" into an "else if"
2298 by providing another condition. */
2301 expand_elseif (cond
)
2304 cond_stack
->data
.cond
.next_label
= gen_label_rtx ();
2305 do_jump (cond
, cond_stack
->data
.cond
.next_label
, NULL_RTX
);
2308 /* Generate RTL for the end of an if-then.
2309 Pop the record for it off of cond_stack. */
2314 struct nesting
*thiscond
= cond_stack
;
2316 do_pending_stack_adjust ();
2317 if (thiscond
->data
.cond
.next_label
)
2318 emit_label (thiscond
->data
.cond
.next_label
);
2319 if (thiscond
->data
.cond
.endif_label
)
2320 emit_label (thiscond
->data
.cond
.endif_label
);
2322 POPSTACK (cond_stack
);
2326 /* Generate RTL for the start of a loop. EXIT_FLAG is nonzero if this
2327 loop should be exited by `exit_something'. This is a loop for which
2328 `expand_continue' will jump to the top of the loop.
2330 Make an entry on loop_stack to record the labels associated with
2334 expand_start_loop (exit_flag
)
2337 register struct nesting
*thisloop
= ALLOC_NESTING ();
2339 /* Make an entry on loop_stack for the loop we are entering. */
2341 thisloop
->next
= loop_stack
;
2342 thisloop
->all
= nesting_stack
;
2343 thisloop
->depth
= ++nesting_depth
;
2344 thisloop
->data
.loop
.start_label
= gen_label_rtx ();
2345 thisloop
->data
.loop
.end_label
= gen_label_rtx ();
2346 thisloop
->data
.loop
.alt_end_label
= 0;
2347 thisloop
->data
.loop
.continue_label
= thisloop
->data
.loop
.start_label
;
2348 thisloop
->exit_label
= exit_flag
? thisloop
->data
.loop
.end_label
: 0;
2349 loop_stack
= thisloop
;
2350 nesting_stack
= thisloop
;
2352 do_pending_stack_adjust ();
2354 emit_note (NULL
, NOTE_INSN_LOOP_BEG
);
2355 emit_label (thisloop
->data
.loop
.start_label
);
2360 /* Like expand_start_loop but for a loop where the continuation point
2361 (for expand_continue_loop) will be specified explicitly. */
2364 expand_start_loop_continue_elsewhere (exit_flag
)
2367 struct nesting
*thisloop
= expand_start_loop (exit_flag
);
2368 loop_stack
->data
.loop
.continue_label
= gen_label_rtx ();
2372 /* Begin a null, aka do { } while (0) "loop". But since the contents
2373 of said loop can still contain a break, we must frob the loop nest. */
2376 expand_start_null_loop ()
2378 register struct nesting
*thisloop
= ALLOC_NESTING ();
2380 /* Make an entry on loop_stack for the loop we are entering. */
2382 thisloop
->next
= loop_stack
;
2383 thisloop
->all
= nesting_stack
;
2384 thisloop
->depth
= ++nesting_depth
;
2385 thisloop
->data
.loop
.start_label
= emit_note (NULL
, NOTE_INSN_DELETED
);
2386 thisloop
->data
.loop
.end_label
= gen_label_rtx ();
2387 thisloop
->data
.loop
.alt_end_label
= NULL_RTX
;
2388 thisloop
->data
.loop
.continue_label
= thisloop
->data
.loop
.end_label
;
2389 thisloop
->exit_label
= thisloop
->data
.loop
.end_label
;
2390 loop_stack
= thisloop
;
2391 nesting_stack
= thisloop
;
2396 /* Specify the continuation point for a loop started with
2397 expand_start_loop_continue_elsewhere.
2398 Use this at the point in the code to which a continue statement
2402 expand_loop_continue_here ()
2404 do_pending_stack_adjust ();
2405 emit_note (NULL
, NOTE_INSN_LOOP_CONT
);
2406 emit_label (loop_stack
->data
.loop
.continue_label
);
2409 /* Finish a loop. Generate a jump back to the top and the loop-exit label.
2410 Pop the block off of loop_stack. */
2415 rtx start_label
= loop_stack
->data
.loop
.start_label
;
2416 rtx insn
= get_last_insn ();
2417 int needs_end_jump
= 1;
2419 /* Mark the continue-point at the top of the loop if none elsewhere. */
2420 if (start_label
== loop_stack
->data
.loop
.continue_label
)
2421 emit_note_before (NOTE_INSN_LOOP_CONT
, start_label
);
2423 do_pending_stack_adjust ();
2425 /* If optimizing, perhaps reorder the loop.
2426 First, try to use a condjump near the end.
2427 expand_exit_loop_if_false ends loops with unconditional jumps,
2430 if (test) goto label;
2432 goto loop_stack->data.loop.end_label
2436 If we find such a pattern, we can end the loop earlier. */
2439 && GET_CODE (insn
) == CODE_LABEL
2440 && LABEL_NAME (insn
) == NULL
2441 && GET_CODE (PREV_INSN (insn
)) == BARRIER
)
2444 rtx jump
= PREV_INSN (PREV_INSN (label
));
2446 if (GET_CODE (jump
) == JUMP_INSN
2447 && GET_CODE (PATTERN (jump
)) == SET
2448 && SET_DEST (PATTERN (jump
)) == pc_rtx
2449 && GET_CODE (SET_SRC (PATTERN (jump
))) == LABEL_REF
2450 && (XEXP (SET_SRC (PATTERN (jump
)), 0)
2451 == loop_stack
->data
.loop
.end_label
))
2455 /* The test might be complex and reference LABEL multiple times,
2456 like the loop in loop_iterations to set vtop. To handle this,
2458 insn
= PREV_INSN (label
);
2459 reorder_insns (label
, label
, start_label
);
2461 for (prev
= PREV_INSN (jump
);; prev
= PREV_INSN (prev
))
2463 /* We ignore line number notes, but if we see any other note,
2464 in particular NOTE_INSN_BLOCK_*, NOTE_INSN_EH_REGION_*,
2465 NOTE_INSN_LOOP_*, we disable this optimization. */
2466 if (GET_CODE (prev
) == NOTE
)
2468 if (NOTE_LINE_NUMBER (prev
) < 0)
2472 if (GET_CODE (prev
) == CODE_LABEL
)
2474 if (GET_CODE (prev
) == JUMP_INSN
)
2476 if (GET_CODE (PATTERN (prev
)) == SET
2477 && SET_DEST (PATTERN (prev
)) == pc_rtx
2478 && GET_CODE (SET_SRC (PATTERN (prev
))) == IF_THEN_ELSE
2479 && (GET_CODE (XEXP (SET_SRC (PATTERN (prev
)), 1))
2481 && XEXP (XEXP (SET_SRC (PATTERN (prev
)), 1), 0) == label
)
2483 XEXP (XEXP (SET_SRC (PATTERN (prev
)), 1), 0)
2485 emit_note_after (NOTE_INSN_LOOP_END
, prev
);
2494 /* If the loop starts with a loop exit, roll that to the end where
2495 it will optimize together with the jump back.
2497 We look for the conditional branch to the exit, except that once
2498 we find such a branch, we don't look past 30 instructions.
2500 In more detail, if the loop presently looks like this (in pseudo-C):
2503 if (test) goto end_label;
2508 transform it to look like:
2514 if (test) goto end_label;
2515 goto newstart_label;
2518 Here, the `test' may actually consist of some reasonably complex
2519 code, terminating in a test. */
2524 ! (GET_CODE (insn
) == JUMP_INSN
2525 && GET_CODE (PATTERN (insn
)) == SET
2526 && SET_DEST (PATTERN (insn
)) == pc_rtx
2527 && GET_CODE (SET_SRC (PATTERN (insn
))) == IF_THEN_ELSE
))
2531 rtx last_test_insn
= NULL_RTX
;
2533 /* Scan insns from the top of the loop looking for a qualified
2534 conditional exit. */
2535 for (insn
= NEXT_INSN (loop_stack
->data
.loop
.start_label
); insn
;
2536 insn
= NEXT_INSN (insn
))
2538 if (GET_CODE (insn
) == NOTE
)
2541 && (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
2542 || NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
))
2543 /* The code that actually moves the exit test will
2544 carefully leave BLOCK notes in their original
2545 location. That means, however, that we can't debug
2546 the exit test itself. So, we refuse to move code
2547 containing BLOCK notes at low optimization levels. */
2550 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EH_REGION_BEG
)
2552 else if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EH_REGION_END
)
2556 /* We've come to the end of an EH region, but
2557 never saw the beginning of that region. That
2558 means that an EH region begins before the top
2559 of the loop, and ends in the middle of it. The
2560 existence of such a situation violates a basic
2561 assumption in this code, since that would imply
2562 that even when EH_REGIONS is zero, we might
2563 move code out of an exception region. */
2567 /* We must not walk into a nested loop. */
2568 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_LOOP_BEG
)
2571 /* We already know this INSN is a NOTE, so there's no
2572 point in looking at it to see if it's a JUMP. */
2576 if (GET_CODE (insn
) == JUMP_INSN
|| GET_CODE (insn
) == INSN
)
2579 if (last_test_insn
&& num_insns
> 30)
2583 /* We don't want to move a partial EH region. Consider:
2597 This isn't legal C++, but here's what it's supposed to
2598 mean: if cond() is true, stop looping. Otherwise,
2599 call bar, and keep looping. In addition, if cond
2600 throws an exception, catch it and keep looping. Such
2601 constructs are certainy legal in LISP.
2603 We should not move the `if (cond()) 0' test since then
2604 the EH-region for the try-block would be broken up.
2605 (In this case we would the EH_BEG note for the `try'
2606 and `if cond()' but not the call to bar() or the
2609 So we don't look for tests within an EH region. */
2612 if (GET_CODE (insn
) == JUMP_INSN
2613 && GET_CODE (PATTERN (insn
)) == SET
2614 && SET_DEST (PATTERN (insn
)) == pc_rtx
)
2616 /* This is indeed a jump. */
2617 rtx dest1
= NULL_RTX
;
2618 rtx dest2
= NULL_RTX
;
2619 rtx potential_last_test
;
2620 if (GET_CODE (SET_SRC (PATTERN (insn
))) == IF_THEN_ELSE
)
2622 /* A conditional jump. */
2623 dest1
= XEXP (SET_SRC (PATTERN (insn
)), 1);
2624 dest2
= XEXP (SET_SRC (PATTERN (insn
)), 2);
2625 potential_last_test
= insn
;
2629 /* An unconditional jump. */
2630 dest1
= SET_SRC (PATTERN (insn
));
2631 /* Include the BARRIER after the JUMP. */
2632 potential_last_test
= NEXT_INSN (insn
);
2636 if (dest1
&& GET_CODE (dest1
) == LABEL_REF
2637 && ((XEXP (dest1
, 0)
2638 == loop_stack
->data
.loop
.alt_end_label
)
2640 == loop_stack
->data
.loop
.end_label
)))
2642 last_test_insn
= potential_last_test
;
2646 /* If this was a conditional jump, there may be
2647 another label at which we should look. */
2654 if (last_test_insn
!= 0 && last_test_insn
!= get_last_insn ())
2656 /* We found one. Move everything from there up
2657 to the end of the loop, and add a jump into the loop
2658 to jump to there. */
2659 register rtx newstart_label
= gen_label_rtx ();
2660 register rtx start_move
= start_label
;
2663 /* If the start label is preceded by a NOTE_INSN_LOOP_CONT note,
2664 then we want to move this note also. */
2665 if (GET_CODE (PREV_INSN (start_move
)) == NOTE
2666 && (NOTE_LINE_NUMBER (PREV_INSN (start_move
))
2667 == NOTE_INSN_LOOP_CONT
))
2668 start_move
= PREV_INSN (start_move
);
2670 emit_label_after (newstart_label
, PREV_INSN (start_move
));
2672 /* Actually move the insns. Start at the beginning, and
2673 keep copying insns until we've copied the
2675 for (insn
= start_move
; insn
; insn
= next_insn
)
2677 /* Figure out which insn comes after this one. We have
2678 to do this before we move INSN. */
2679 if (insn
== last_test_insn
)
2680 /* We've moved all the insns. */
2681 next_insn
= NULL_RTX
;
2683 next_insn
= NEXT_INSN (insn
);
2685 if (GET_CODE (insn
) == NOTE
2686 && (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
2687 || NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
))
2688 /* We don't want to move NOTE_INSN_BLOCK_BEGs or
2689 NOTE_INSN_BLOCK_ENDs because the correct generation
2690 of debugging information depends on these appearing
2691 in the same order in the RTL and in the tree
2692 structure, where they are represented as BLOCKs.
2693 So, we don't move block notes. Of course, moving
2694 the code inside the block is likely to make it
2695 impossible to debug the instructions in the exit
2696 test, but such is the price of optimization. */
2699 /* Move the INSN. */
2700 reorder_insns (insn
, insn
, get_last_insn ());
2703 emit_jump_insn_after (gen_jump (start_label
),
2704 PREV_INSN (newstart_label
));
2705 emit_barrier_after (PREV_INSN (newstart_label
));
2706 start_label
= newstart_label
;
2712 emit_jump (start_label
);
2713 emit_note (NULL
, NOTE_INSN_LOOP_END
);
2715 emit_label (loop_stack
->data
.loop
.end_label
);
2717 POPSTACK (loop_stack
);
2722 /* Finish a null loop, aka do { } while (0). */
2725 expand_end_null_loop ()
2727 do_pending_stack_adjust ();
2728 emit_label (loop_stack
->data
.loop
.end_label
);
2730 POPSTACK (loop_stack
);
2735 /* Generate a jump to the current loop's continue-point.
2736 This is usually the top of the loop, but may be specified
2737 explicitly elsewhere. If not currently inside a loop,
2738 return 0 and do nothing; caller will print an error message. */
2741 expand_continue_loop (whichloop
)
2742 struct nesting
*whichloop
;
2746 whichloop
= loop_stack
;
2749 expand_goto_internal (NULL_TREE
, whichloop
->data
.loop
.continue_label
,
2754 /* Generate a jump to exit the current loop. If not currently inside a loop,
2755 return 0 and do nothing; caller will print an error message. */
2758 expand_exit_loop (whichloop
)
2759 struct nesting
*whichloop
;
2763 whichloop
= loop_stack
;
2766 expand_goto_internal (NULL_TREE
, whichloop
->data
.loop
.end_label
, NULL_RTX
);
2770 /* Generate a conditional jump to exit the current loop if COND
2771 evaluates to zero. If not currently inside a loop,
2772 return 0 and do nothing; caller will print an error message. */
2775 expand_exit_loop_if_false (whichloop
, cond
)
2776 struct nesting
*whichloop
;
2779 rtx label
= gen_label_rtx ();
2784 whichloop
= loop_stack
;
2787 /* In order to handle fixups, we actually create a conditional jump
2788 around a unconditional branch to exit the loop. If fixups are
2789 necessary, they go before the unconditional branch. */
2791 do_jump (cond
, NULL_RTX
, label
);
2792 last_insn
= get_last_insn ();
2793 if (GET_CODE (last_insn
) == CODE_LABEL
)
2794 whichloop
->data
.loop
.alt_end_label
= last_insn
;
2795 expand_goto_internal (NULL_TREE
, whichloop
->data
.loop
.end_label
,
2802 /* Return nonzero if the loop nest is empty. Else return zero. */
2805 stmt_loop_nest_empty ()
2807 /* cfun->stmt can be NULL if we are building a call to get the
2808 EH context for a setjmp/longjmp EH target and the current
2809 function was a deferred inline function. */
2810 return (cfun
->stmt
== NULL
|| loop_stack
== NULL
);
2813 /* Return non-zero if we should preserve sub-expressions as separate
2814 pseudos. We never do so if we aren't optimizing. We always do so
2815 if -fexpensive-optimizations.
2817 Otherwise, we only do so if we are in the "early" part of a loop. I.e.,
2818 the loop may still be a small one. */
2821 preserve_subexpressions_p ()
2825 if (flag_expensive_optimizations
)
2828 if (optimize
== 0 || cfun
== 0 || cfun
->stmt
== 0 || loop_stack
== 0)
2831 insn
= get_last_insn_anywhere ();
2834 && (INSN_UID (insn
) - INSN_UID (loop_stack
->data
.loop
.start_label
)
2835 < n_non_fixed_regs
* 3));
2839 /* Generate a jump to exit the current loop, conditional, binding contour
2840 or case statement. Not all such constructs are visible to this function,
2841 only those started with EXIT_FLAG nonzero. Individual languages use
2842 the EXIT_FLAG parameter to control which kinds of constructs you can
2845 If not currently inside anything that can be exited,
2846 return 0 and do nothing; caller will print an error message. */
2849 expand_exit_something ()
2853 for (n
= nesting_stack
; n
; n
= n
->all
)
2854 if (n
->exit_label
!= 0)
2856 expand_goto_internal (NULL_TREE
, n
->exit_label
, NULL_RTX
);
2863 /* Generate RTL to return from the current function, with no value.
2864 (That is, we do not do anything about returning any value.) */
2867 expand_null_return ()
2869 rtx last_insn
= get_last_insn ();
2871 /* If this function was declared to return a value, but we
2872 didn't, clobber the return registers so that they are not
2873 propogated live to the rest of the function. */
2874 clobber_return_register ();
2876 expand_null_return_1 (last_insn
);
2879 /* Generate RTL to return from the current function, with value VAL. */
2882 expand_value_return (val
)
2885 rtx last_insn
= get_last_insn ();
2886 rtx return_reg
= DECL_RTL (DECL_RESULT (current_function_decl
));
2888 /* Copy the value to the return location
2889 unless it's already there. */
2891 if (return_reg
!= val
)
2893 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
2894 #ifdef PROMOTE_FUNCTION_RETURN
2895 int unsignedp
= TREE_UNSIGNED (type
);
2896 enum machine_mode old_mode
2897 = DECL_MODE (DECL_RESULT (current_function_decl
));
2898 enum machine_mode mode
2899 = promote_mode (type
, old_mode
, &unsignedp
, 1);
2901 if (mode
!= old_mode
)
2902 val
= convert_modes (mode
, old_mode
, val
, unsignedp
);
2904 if (GET_CODE (return_reg
) == PARALLEL
)
2905 emit_group_load (return_reg
, val
, int_size_in_bytes (type
),
2908 emit_move_insn (return_reg
, val
);
2911 expand_null_return_1 (last_insn
);
2914 /* Output a return with no value. If LAST_INSN is nonzero,
2915 pretend that the return takes place after LAST_INSN. */
2918 expand_null_return_1 (last_insn
)
2921 rtx end_label
= cleanup_label
? cleanup_label
: return_label
;
2923 clear_pending_stack_adjust ();
2924 do_pending_stack_adjust ();
2928 end_label
= return_label
= gen_label_rtx ();
2929 expand_goto_internal (NULL_TREE
, end_label
, last_insn
);
2932 /* Generate RTL to evaluate the expression RETVAL and return it
2933 from the current function. */
2936 expand_return (retval
)
2939 /* If there are any cleanups to be performed, then they will
2940 be inserted following LAST_INSN. It is desirable
2941 that the last_insn, for such purposes, should be the
2942 last insn before computing the return value. Otherwise, cleanups
2943 which call functions can clobber the return value. */
2944 /* ??? rms: I think that is erroneous, because in C++ it would
2945 run destructors on variables that might be used in the subsequent
2946 computation of the return value. */
2949 register rtx val
= 0;
2952 /* If function wants no value, give it none. */
2953 if (TREE_CODE (TREE_TYPE (TREE_TYPE (current_function_decl
))) == VOID_TYPE
)
2955 expand_expr (retval
, NULL_RTX
, VOIDmode
, 0);
2957 expand_null_return ();
2961 if (retval
== error_mark_node
)
2963 /* Treat this like a return of no value from a function that
2965 expand_null_return ();
2968 else if (TREE_CODE (retval
) == RESULT_DECL
)
2969 retval_rhs
= retval
;
2970 else if ((TREE_CODE (retval
) == MODIFY_EXPR
|| TREE_CODE (retval
) == INIT_EXPR
)
2971 && TREE_CODE (TREE_OPERAND (retval
, 0)) == RESULT_DECL
)
2972 retval_rhs
= TREE_OPERAND (retval
, 1);
2973 else if (VOID_TYPE_P (TREE_TYPE (retval
)))
2974 /* Recognize tail-recursive call to void function. */
2975 retval_rhs
= retval
;
2977 retval_rhs
= NULL_TREE
;
2979 last_insn
= get_last_insn ();
2981 /* Distribute return down conditional expr if either of the sides
2982 may involve tail recursion (see test below). This enhances the number
2983 of tail recursions we see. Don't do this always since it can produce
2984 sub-optimal code in some cases and we distribute assignments into
2985 conditional expressions when it would help. */
2987 if (optimize
&& retval_rhs
!= 0
2988 && frame_offset
== 0
2989 && TREE_CODE (retval_rhs
) == COND_EXPR
2990 && (TREE_CODE (TREE_OPERAND (retval_rhs
, 1)) == CALL_EXPR
2991 || TREE_CODE (TREE_OPERAND (retval_rhs
, 2)) == CALL_EXPR
))
2993 rtx label
= gen_label_rtx ();
2996 do_jump (TREE_OPERAND (retval_rhs
, 0), label
, NULL_RTX
);
2997 start_cleanup_deferral ();
2998 expr
= build (MODIFY_EXPR
, TREE_TYPE (TREE_TYPE (current_function_decl
)),
2999 DECL_RESULT (current_function_decl
),
3000 TREE_OPERAND (retval_rhs
, 1));
3001 TREE_SIDE_EFFECTS (expr
) = 1;
3002 expand_return (expr
);
3005 expr
= build (MODIFY_EXPR
, TREE_TYPE (TREE_TYPE (current_function_decl
)),
3006 DECL_RESULT (current_function_decl
),
3007 TREE_OPERAND (retval_rhs
, 2));
3008 TREE_SIDE_EFFECTS (expr
) = 1;
3009 expand_return (expr
);
3010 end_cleanup_deferral ();
3014 result_rtl
= DECL_RTL (DECL_RESULT (current_function_decl
));
3016 /* If the result is an aggregate that is being returned in one (or more)
3017 registers, load the registers here. The compiler currently can't handle
3018 copying a BLKmode value into registers. We could put this code in a
3019 more general area (for use by everyone instead of just function
3020 call/return), but until this feature is generally usable it is kept here
3021 (and in expand_call). The value must go into a pseudo in case there
3022 are cleanups that will clobber the real return register. */
3025 && TYPE_MODE (TREE_TYPE (retval_rhs
)) == BLKmode
3026 && GET_CODE (result_rtl
) == REG
)
3029 unsigned HOST_WIDE_INT bitpos
, xbitpos
;
3030 unsigned HOST_WIDE_INT big_endian_correction
= 0;
3031 unsigned HOST_WIDE_INT bytes
3032 = int_size_in_bytes (TREE_TYPE (retval_rhs
));
3033 int n_regs
= (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
3034 unsigned int bitsize
3035 = MIN (TYPE_ALIGN (TREE_TYPE (retval_rhs
)), BITS_PER_WORD
);
3036 rtx
*result_pseudos
= (rtx
*) alloca (sizeof (rtx
) * n_regs
);
3037 rtx result_reg
, src
= NULL_RTX
, dst
= NULL_RTX
;
3038 rtx result_val
= expand_expr (retval_rhs
, NULL_RTX
, VOIDmode
, 0);
3039 enum machine_mode tmpmode
, result_reg_mode
;
3043 expand_null_return ();
3047 /* Structures whose size is not a multiple of a word are aligned
3048 to the least significant byte (to the right). On a BYTES_BIG_ENDIAN
3049 machine, this means we must skip the empty high order bytes when
3050 calculating the bit offset. */
3051 if (BYTES_BIG_ENDIAN
&& bytes
% UNITS_PER_WORD
)
3052 big_endian_correction
= (BITS_PER_WORD
- ((bytes
% UNITS_PER_WORD
)
3055 /* Copy the structure BITSIZE bits at a time. */
3056 for (bitpos
= 0, xbitpos
= big_endian_correction
;
3057 bitpos
< bytes
* BITS_PER_UNIT
;
3058 bitpos
+= bitsize
, xbitpos
+= bitsize
)
3060 /* We need a new destination pseudo each time xbitpos is
3061 on a word boundary and when xbitpos == big_endian_correction
3062 (the first time through). */
3063 if (xbitpos
% BITS_PER_WORD
== 0
3064 || xbitpos
== big_endian_correction
)
3066 /* Generate an appropriate register. */
3067 dst
= gen_reg_rtx (word_mode
);
3068 result_pseudos
[xbitpos
/ BITS_PER_WORD
] = dst
;
3070 /* Clobber the destination before we move anything into it. */
3071 emit_insn (gen_rtx_CLOBBER (VOIDmode
, dst
));
3074 /* We need a new source operand each time bitpos is on a word
3076 if (bitpos
% BITS_PER_WORD
== 0)
3077 src
= operand_subword_force (result_val
,
3078 bitpos
/ BITS_PER_WORD
,
3081 /* Use bitpos for the source extraction (left justified) and
3082 xbitpos for the destination store (right justified). */
3083 store_bit_field (dst
, bitsize
, xbitpos
% BITS_PER_WORD
, word_mode
,
3084 extract_bit_field (src
, bitsize
,
3085 bitpos
% BITS_PER_WORD
, 1,
3086 NULL_RTX
, word_mode
, word_mode
,
3087 bitsize
, BITS_PER_WORD
),
3088 bitsize
, BITS_PER_WORD
);
3091 /* Find the smallest integer mode large enough to hold the
3092 entire structure and use that mode instead of BLKmode
3093 on the USE insn for the return register. */
3094 for (tmpmode
= GET_CLASS_NARROWEST_MODE (MODE_INT
);
3095 tmpmode
!= VOIDmode
;
3096 tmpmode
= GET_MODE_WIDER_MODE (tmpmode
))
3097 /* Have we found a large enough mode? */
3098 if (GET_MODE_SIZE (tmpmode
) >= bytes
)
3101 /* No suitable mode found. */
3102 if (tmpmode
== VOIDmode
)
3105 PUT_MODE (result_rtl
, tmpmode
);
3107 if (GET_MODE_SIZE (tmpmode
) < GET_MODE_SIZE (word_mode
))
3108 result_reg_mode
= word_mode
;
3110 result_reg_mode
= tmpmode
;
3111 result_reg
= gen_reg_rtx (result_reg_mode
);
3114 for (i
= 0; i
< n_regs
; i
++)
3115 emit_move_insn (operand_subword (result_reg
, i
, 0, result_reg_mode
),
3118 if (tmpmode
!= result_reg_mode
)
3119 result_reg
= gen_lowpart (tmpmode
, result_reg
);
3121 expand_value_return (result_reg
);
3123 else if (retval_rhs
!= 0
3124 && !VOID_TYPE_P (TREE_TYPE (retval_rhs
))
3125 && (GET_CODE (result_rtl
) == REG
3126 || (GET_CODE (result_rtl
) == PARALLEL
)))
3128 /* Calculate the return value into a temporary (usually a pseudo
3130 tree ot
= TREE_TYPE (DECL_RESULT (current_function_decl
));
3131 tree nt
= build_qualified_type (ot
, TYPE_QUALS (ot
) | TYPE_QUAL_CONST
);
3133 val
= assign_temp (nt
, 0, 0, 1);
3134 val
= expand_expr (retval_rhs
, val
, GET_MODE (val
), 0);
3135 val
= force_not_mem (val
);
3137 /* Return the calculated value, doing cleanups first. */
3138 expand_value_return (val
);
3142 /* No cleanups or no hard reg used;
3143 calculate value into hard return reg. */
3144 expand_expr (retval
, const0_rtx
, VOIDmode
, 0);
3146 expand_value_return (result_rtl
);
3150 /* Return 1 if the end of the generated RTX is not a barrier.
3151 This means code already compiled can drop through. */
3154 drop_through_at_end_p ()
3156 rtx insn
= get_last_insn ();
3157 while (insn
&& GET_CODE (insn
) == NOTE
)
3158 insn
= PREV_INSN (insn
);
3159 return insn
&& GET_CODE (insn
) != BARRIER
;
3162 /* Attempt to optimize a potential tail recursion call into a goto.
3163 ARGUMENTS are the arguments to a CALL_EXPR; LAST_INSN indicates
3164 where to place the jump to the tail recursion label.
3166 Return TRUE if the call was optimized into a goto. */
3169 optimize_tail_recursion (arguments
, last_insn
)
3173 /* Finish checking validity, and if valid emit code to set the
3174 argument variables for the new call. */
3175 if (tail_recursion_args (arguments
, DECL_ARGUMENTS (current_function_decl
)))
3177 if (tail_recursion_label
== 0)
3179 tail_recursion_label
= gen_label_rtx ();
3180 emit_label_after (tail_recursion_label
,
3181 tail_recursion_reentry
);
3184 expand_goto_internal (NULL_TREE
, tail_recursion_label
, last_insn
);
3191 /* Emit code to alter this function's formal parms for a tail-recursive call.
3192 ACTUALS is a list of actual parameter expressions (chain of TREE_LISTs).
3193 FORMALS is the chain of decls of formals.
3194 Return 1 if this can be done;
3195 otherwise return 0 and do not emit any code. */
3198 tail_recursion_args (actuals
, formals
)
3199 tree actuals
, formals
;
3201 register tree a
= actuals
, f
= formals
;
3203 register rtx
*argvec
;
3205 /* Check that number and types of actuals are compatible
3206 with the formals. This is not always true in valid C code.
3207 Also check that no formal needs to be addressable
3208 and that all formals are scalars. */
3210 /* Also count the args. */
3212 for (a
= actuals
, f
= formals
, i
= 0; a
&& f
; a
= TREE_CHAIN (a
), f
= TREE_CHAIN (f
), i
++)
3214 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_VALUE (a
)))
3215 != TYPE_MAIN_VARIANT (TREE_TYPE (f
)))
3217 if (GET_CODE (DECL_RTL (f
)) != REG
|| DECL_MODE (f
) == BLKmode
)
3220 if (a
!= 0 || f
!= 0)
3223 /* Compute all the actuals. */
3225 argvec
= (rtx
*) alloca (i
* sizeof (rtx
));
3227 for (a
= actuals
, i
= 0; a
; a
= TREE_CHAIN (a
), i
++)
3228 argvec
[i
] = expand_expr (TREE_VALUE (a
), NULL_RTX
, VOIDmode
, 0);
3230 /* Find which actual values refer to current values of previous formals.
3231 Copy each of them now, before any formal is changed. */
3233 for (a
= actuals
, i
= 0; a
; a
= TREE_CHAIN (a
), i
++)
3237 for (f
= formals
, j
= 0; j
< i
; f
= TREE_CHAIN (f
), j
++)
3238 if (reg_mentioned_p (DECL_RTL (f
), argvec
[i
]))
3244 argvec
[i
] = copy_to_reg (argvec
[i
]);
3247 /* Store the values of the actuals into the formals. */
3249 for (f
= formals
, a
= actuals
, i
= 0; f
;
3250 f
= TREE_CHAIN (f
), a
= TREE_CHAIN (a
), i
++)
3252 if (GET_MODE (DECL_RTL (f
)) == GET_MODE (argvec
[i
]))
3253 emit_move_insn (DECL_RTL (f
), argvec
[i
]);
3255 convert_move (DECL_RTL (f
), argvec
[i
],
3256 TREE_UNSIGNED (TREE_TYPE (TREE_VALUE (a
))));
3263 /* Generate the RTL code for entering a binding contour.
3264 The variables are declared one by one, by calls to `expand_decl'.
3266 FLAGS is a bitwise or of the following flags:
3268 1 - Nonzero if this construct should be visible to
3271 2 - Nonzero if this contour does not require a
3272 NOTE_INSN_BLOCK_BEG note. Virtually all calls from
3273 language-independent code should set this flag because they
3274 will not create corresponding BLOCK nodes. (There should be
3275 a one-to-one correspondence between NOTE_INSN_BLOCK_BEG notes
3276 and BLOCKs.) If this flag is set, MARK_ENDS should be zero
3277 when expand_end_bindings is called.
3279 If we are creating a NOTE_INSN_BLOCK_BEG note, a BLOCK may
3280 optionally be supplied. If so, it becomes the NOTE_BLOCK for the
3284 expand_start_bindings_and_block (flags
, block
)
3288 struct nesting
*thisblock
= ALLOC_NESTING ();
3290 int exit_flag
= ((flags
& 1) != 0);
3291 int block_flag
= ((flags
& 2) == 0);
3293 /* If a BLOCK is supplied, then the caller should be requesting a
3294 NOTE_INSN_BLOCK_BEG note. */
3295 if (!block_flag
&& block
)
3298 /* Create a note to mark the beginning of the block. */
3301 note
= emit_note (NULL
, NOTE_INSN_BLOCK_BEG
);
3302 NOTE_BLOCK (note
) = block
;
3305 note
= emit_note (NULL
, NOTE_INSN_DELETED
);
3307 /* Make an entry on block_stack for the block we are entering. */
3309 thisblock
->next
= block_stack
;
3310 thisblock
->all
= nesting_stack
;
3311 thisblock
->depth
= ++nesting_depth
;
3312 thisblock
->data
.block
.stack_level
= 0;
3313 thisblock
->data
.block
.cleanups
= 0;
3314 thisblock
->data
.block
.n_function_calls
= 0;
3315 thisblock
->data
.block
.exception_region
= 0;
3316 thisblock
->data
.block
.block_target_temp_slot_level
= target_temp_slot_level
;
3318 thisblock
->data
.block
.conditional_code
= 0;
3319 thisblock
->data
.block
.last_unconditional_cleanup
= note
;
3320 /* When we insert instructions after the last unconditional cleanup,
3321 we don't adjust last_insn. That means that a later add_insn will
3322 clobber the instructions we've just added. The easiest way to
3323 fix this is to just insert another instruction here, so that the
3324 instructions inserted after the last unconditional cleanup are
3325 never the last instruction. */
3326 emit_note (NULL
, NOTE_INSN_DELETED
);
3327 thisblock
->data
.block
.cleanup_ptr
= &thisblock
->data
.block
.cleanups
;
3330 && !(block_stack
->data
.block
.cleanups
== NULL_TREE
3331 && block_stack
->data
.block
.outer_cleanups
== NULL_TREE
))
3332 thisblock
->data
.block
.outer_cleanups
3333 = tree_cons (NULL_TREE
, block_stack
->data
.block
.cleanups
,
3334 block_stack
->data
.block
.outer_cleanups
);
3336 thisblock
->data
.block
.outer_cleanups
= 0;
3337 thisblock
->data
.block
.label_chain
= 0;
3338 thisblock
->data
.block
.innermost_stack_block
= stack_block_stack
;
3339 thisblock
->data
.block
.first_insn
= note
;
3340 thisblock
->data
.block
.block_start_count
= ++current_block_start_count
;
3341 thisblock
->exit_label
= exit_flag
? gen_label_rtx () : 0;
3342 block_stack
= thisblock
;
3343 nesting_stack
= thisblock
;
3345 /* Make a new level for allocating stack slots. */
3349 /* Specify the scope of temporaries created by TARGET_EXPRs. Similar
3350 to CLEANUP_POINT_EXPR, but handles cases when a series of calls to
3351 expand_expr are made. After we end the region, we know that all
3352 space for all temporaries that were created by TARGET_EXPRs will be
3353 destroyed and their space freed for reuse. */
3356 expand_start_target_temps ()
3358 /* This is so that even if the result is preserved, the space
3359 allocated will be freed, as we know that it is no longer in use. */
3362 /* Start a new binding layer that will keep track of all cleanup
3363 actions to be performed. */
3364 expand_start_bindings (2);
3366 target_temp_slot_level
= temp_slot_level
;
3370 expand_end_target_temps ()
3372 expand_end_bindings (NULL_TREE
, 0, 0);
3374 /* This is so that even if the result is preserved, the space
3375 allocated will be freed, as we know that it is no longer in use. */
3379 /* Given a pointer to a BLOCK node return non-zero if (and only if) the node
3380 in question represents the outermost pair of curly braces (i.e. the "body
3381 block") of a function or method.
3383 For any BLOCK node representing a "body block" of a function or method, the
3384 BLOCK_SUPERCONTEXT of the node will point to another BLOCK node which
3385 represents the outermost (function) scope for the function or method (i.e.
3386 the one which includes the formal parameters). The BLOCK_SUPERCONTEXT of
3387 *that* node in turn will point to the relevant FUNCTION_DECL node. */
3390 is_body_block (stmt
)
3393 if (TREE_CODE (stmt
) == BLOCK
)
3395 tree parent
= BLOCK_SUPERCONTEXT (stmt
);
3397 if (parent
&& TREE_CODE (parent
) == BLOCK
)
3399 tree grandparent
= BLOCK_SUPERCONTEXT (parent
);
3401 if (grandparent
&& TREE_CODE (grandparent
) == FUNCTION_DECL
)
3409 /* True if we are currently emitting insns in an area of output code
3410 that is controlled by a conditional expression. This is used by
3411 the cleanup handling code to generate conditional cleanup actions. */
3414 conditional_context ()
3416 return block_stack
&& block_stack
->data
.block
.conditional_code
;
3419 /* Return an opaque pointer to the current nesting level, so frontend code
3420 can check its own sanity. */
3423 current_nesting_level ()
3425 return cfun
? block_stack
: 0;
3428 /* Emit a handler label for a nonlocal goto handler.
3429 Also emit code to store the handler label in SLOT before BEFORE_INSN. */
3432 expand_nl_handler_label (slot
, before_insn
)
3433 rtx slot
, before_insn
;
3436 rtx handler_label
= gen_label_rtx ();
3438 /* Don't let cleanup_cfg delete the handler. */
3439 LABEL_PRESERVE_P (handler_label
) = 1;
3442 emit_move_insn (slot
, gen_rtx_LABEL_REF (Pmode
, handler_label
));
3443 insns
= get_insns ();
3445 emit_insns_before (insns
, before_insn
);
3447 emit_label (handler_label
);
3449 return handler_label
;
3452 /* Emit code to restore vital registers at the beginning of a nonlocal goto
3455 expand_nl_goto_receiver ()
3457 #ifdef HAVE_nonlocal_goto
3458 if (! HAVE_nonlocal_goto
)
3460 /* First adjust our frame pointer to its actual value. It was
3461 previously set to the start of the virtual area corresponding to
3462 the stacked variables when we branched here and now needs to be
3463 adjusted to the actual hardware fp value.
3465 Assignments are to virtual registers are converted by
3466 instantiate_virtual_regs into the corresponding assignment
3467 to the underlying register (fp in this case) that makes
3468 the original assignment true.
3469 So the following insn will actually be
3470 decrementing fp by STARTING_FRAME_OFFSET. */
3471 emit_move_insn (virtual_stack_vars_rtx
, hard_frame_pointer_rtx
);
3473 #if ARG_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
3474 if (fixed_regs
[ARG_POINTER_REGNUM
])
3476 #ifdef ELIMINABLE_REGS
3477 /* If the argument pointer can be eliminated in favor of the
3478 frame pointer, we don't need to restore it. We assume here
3479 that if such an elimination is present, it can always be used.
3480 This is the case on all known machines; if we don't make this
3481 assumption, we do unnecessary saving on many machines. */
3482 static struct elims
{int from
, to
;} elim_regs
[] = ELIMINABLE_REGS
;
3485 for (i
= 0; i
< ARRAY_SIZE (elim_regs
); i
++)
3486 if (elim_regs
[i
].from
== ARG_POINTER_REGNUM
3487 && elim_regs
[i
].to
== HARD_FRAME_POINTER_REGNUM
)
3490 if (i
== ARRAY_SIZE (elim_regs
))
3493 /* Now restore our arg pointer from the address at which it
3494 was saved in our stack frame.
3495 If there hasn't be space allocated for it yet, make
3497 if (arg_pointer_save_area
== 0)
3498 arg_pointer_save_area
3499 = assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
3500 emit_move_insn (virtual_incoming_args_rtx
,
3501 /* We need a pseudo here, or else
3502 instantiate_virtual_regs_1 complains. */
3503 copy_to_reg (arg_pointer_save_area
));
3508 #ifdef HAVE_nonlocal_goto_receiver
3509 if (HAVE_nonlocal_goto_receiver
)
3510 emit_insn (gen_nonlocal_goto_receiver ());
3514 /* Make handlers for nonlocal gotos taking place in the function calls in
3518 expand_nl_goto_receivers (thisblock
)
3519 struct nesting
*thisblock
;
3522 rtx afterward
= gen_label_rtx ();
3527 /* Record the handler address in the stack slot for that purpose,
3528 during this block, saving and restoring the outer value. */
3529 if (thisblock
->next
!= 0)
3530 for (slot
= nonlocal_goto_handler_slots
; slot
; slot
= XEXP (slot
, 1))
3532 rtx save_receiver
= gen_reg_rtx (Pmode
);
3533 emit_move_insn (XEXP (slot
, 0), save_receiver
);
3536 emit_move_insn (save_receiver
, XEXP (slot
, 0));
3537 insns
= get_insns ();
3539 emit_insns_before (insns
, thisblock
->data
.block
.first_insn
);
3542 /* Jump around the handlers; they run only when specially invoked. */
3543 emit_jump (afterward
);
3545 /* Make a separate handler for each label. */
3546 link
= nonlocal_labels
;
3547 slot
= nonlocal_goto_handler_slots
;
3548 label_list
= NULL_RTX
;
3549 for (; link
; link
= TREE_CHAIN (link
), slot
= XEXP (slot
, 1))
3550 /* Skip any labels we shouldn't be able to jump to from here,
3551 we generate one special handler for all of them below which just calls
3553 if (! DECL_TOO_LATE (TREE_VALUE (link
)))
3556 lab
= expand_nl_handler_label (XEXP (slot
, 0),
3557 thisblock
->data
.block
.first_insn
);
3558 label_list
= gen_rtx_EXPR_LIST (VOIDmode
, lab
, label_list
);
3560 expand_nl_goto_receiver ();
3562 /* Jump to the "real" nonlocal label. */
3563 expand_goto (TREE_VALUE (link
));
3566 /* A second pass over all nonlocal labels; this time we handle those
3567 we should not be able to jump to at this point. */
3568 link
= nonlocal_labels
;
3569 slot
= nonlocal_goto_handler_slots
;
3571 for (; link
; link
= TREE_CHAIN (link
), slot
= XEXP (slot
, 1))
3572 if (DECL_TOO_LATE (TREE_VALUE (link
)))
3575 lab
= expand_nl_handler_label (XEXP (slot
, 0),
3576 thisblock
->data
.block
.first_insn
);
3577 label_list
= gen_rtx_EXPR_LIST (VOIDmode
, lab
, label_list
);
3583 expand_nl_goto_receiver ();
3584 emit_library_call (gen_rtx_SYMBOL_REF (Pmode
, "abort"), 0,
3589 nonlocal_goto_handler_labels
= label_list
;
3590 emit_label (afterward
);
3593 /* Warn about any unused VARS (which may contain nodes other than
3594 VAR_DECLs, but such nodes are ignored). The nodes are connected
3595 via the TREE_CHAIN field. */
3598 warn_about_unused_variables (vars
)
3603 if (warn_unused_variable
)
3604 for (decl
= vars
; decl
; decl
= TREE_CHAIN (decl
))
3605 if (TREE_CODE (decl
) == VAR_DECL
3606 && ! TREE_USED (decl
)
3607 && ! DECL_IN_SYSTEM_HEADER (decl
)
3608 && DECL_NAME (decl
) && ! DECL_ARTIFICIAL (decl
))
3609 warning_with_decl (decl
, "unused variable `%s'");
3612 /* Generate RTL code to terminate a binding contour.
3614 VARS is the chain of VAR_DECL nodes for the variables bound in this
3615 contour. There may actually be other nodes in this chain, but any
3616 nodes other than VAR_DECLS are ignored.
3618 MARK_ENDS is nonzero if we should put a note at the beginning
3619 and end of this binding contour.
3621 DONT_JUMP_IN is nonzero if it is not valid to jump into this contour.
3622 (That is true automatically if the contour has a saved stack level.) */
3625 expand_end_bindings (vars
, mark_ends
, dont_jump_in
)
3630 register struct nesting
*thisblock
= block_stack
;
3632 /* If any of the variables in this scope were not used, warn the
3634 warn_about_unused_variables (vars
);
3636 if (thisblock
->exit_label
)
3638 do_pending_stack_adjust ();
3639 emit_label (thisblock
->exit_label
);
3642 /* If necessary, make handlers for nonlocal gotos taking
3643 place in the function calls in this block. */
3644 if (function_call_count
!= thisblock
->data
.block
.n_function_calls
3646 /* Make handler for outermost block
3647 if there were any nonlocal gotos to this function. */
3648 && (thisblock
->next
== 0 ? current_function_has_nonlocal_label
3649 /* Make handler for inner block if it has something
3650 special to do when you jump out of it. */
3651 : (thisblock
->data
.block
.cleanups
!= 0
3652 || thisblock
->data
.block
.stack_level
!= 0)))
3653 expand_nl_goto_receivers (thisblock
);
3655 /* Don't allow jumping into a block that has a stack level.
3656 Cleanups are allowed, though. */
3658 || thisblock
->data
.block
.stack_level
!= 0)
3660 struct label_chain
*chain
;
3662 /* Any labels in this block are no longer valid to go to.
3663 Mark them to cause an error message. */
3664 for (chain
= thisblock
->data
.block
.label_chain
; chain
; chain
= chain
->next
)
3666 DECL_TOO_LATE (chain
->label
) = 1;
3667 /* If any goto without a fixup came to this label,
3668 that must be an error, because gotos without fixups
3669 come from outside all saved stack-levels. */
3670 if (TREE_ADDRESSABLE (chain
->label
))
3671 error_with_decl (chain
->label
,
3672 "label `%s' used before containing binding contour");
3676 /* Restore stack level in effect before the block
3677 (only if variable-size objects allocated). */
3678 /* Perform any cleanups associated with the block. */
3680 if (thisblock
->data
.block
.stack_level
!= 0
3681 || thisblock
->data
.block
.cleanups
!= 0)
3686 /* Don't let cleanups affect ({...}) constructs. */
3687 int old_expr_stmts_for_value
= expr_stmts_for_value
;
3688 rtx old_last_expr_value
= last_expr_value
;
3689 tree old_last_expr_type
= last_expr_type
;
3690 expr_stmts_for_value
= 0;
3692 /* Only clean up here if this point can actually be reached. */
3693 insn
= get_last_insn ();
3694 if (GET_CODE (insn
) == NOTE
)
3695 insn
= prev_nonnote_insn (insn
);
3696 reachable
= (! insn
|| GET_CODE (insn
) != BARRIER
);
3698 /* Do the cleanups. */
3699 expand_cleanups (thisblock
->data
.block
.cleanups
, NULL_TREE
, 0, reachable
);
3701 do_pending_stack_adjust ();
3703 expr_stmts_for_value
= old_expr_stmts_for_value
;
3704 last_expr_value
= old_last_expr_value
;
3705 last_expr_type
= old_last_expr_type
;
3707 /* Restore the stack level. */
3709 if (reachable
&& thisblock
->data
.block
.stack_level
!= 0)
3711 emit_stack_restore (thisblock
->next
? SAVE_BLOCK
: SAVE_FUNCTION
,
3712 thisblock
->data
.block
.stack_level
, NULL_RTX
);
3713 if (nonlocal_goto_handler_slots
!= 0)
3714 emit_stack_save (SAVE_NONLOCAL
, &nonlocal_goto_stack_level
,
3718 /* Any gotos out of this block must also do these things.
3719 Also report any gotos with fixups that came to labels in this
3721 fixup_gotos (thisblock
,
3722 thisblock
->data
.block
.stack_level
,
3723 thisblock
->data
.block
.cleanups
,
3724 thisblock
->data
.block
.first_insn
,
3728 /* Mark the beginning and end of the scope if requested.
3729 We do this now, after running cleanups on the variables
3730 just going out of scope, so they are in scope for their cleanups. */
3734 rtx note
= emit_note (NULL
, NOTE_INSN_BLOCK_END
);
3735 NOTE_BLOCK (note
) = NOTE_BLOCK (thisblock
->data
.block
.first_insn
);
3738 /* Get rid of the beginning-mark if we don't make an end-mark. */
3739 NOTE_LINE_NUMBER (thisblock
->data
.block
.first_insn
) = NOTE_INSN_DELETED
;
3741 /* Restore the temporary level of TARGET_EXPRs. */
3742 target_temp_slot_level
= thisblock
->data
.block
.block_target_temp_slot_level
;
3744 /* Restore block_stack level for containing block. */
3746 stack_block_stack
= thisblock
->data
.block
.innermost_stack_block
;
3747 POPSTACK (block_stack
);
3749 /* Pop the stack slot nesting and free any slots at this level. */
3753 /* Generate code to save the stack pointer at the start of the current block
3754 and set up to restore it on exit. */
3757 save_stack_pointer ()
3759 struct nesting
*thisblock
= block_stack
;
3761 if (thisblock
->data
.block
.stack_level
== 0)
3763 emit_stack_save (thisblock
->next
? SAVE_BLOCK
: SAVE_FUNCTION
,
3764 &thisblock
->data
.block
.stack_level
,
3765 thisblock
->data
.block
.first_insn
);
3766 stack_block_stack
= thisblock
;
3770 /* Generate RTL for the automatic variable declaration DECL.
3771 (Other kinds of declarations are simply ignored if seen here.) */
3777 struct nesting
*thisblock
;
3780 type
= TREE_TYPE (decl
);
3782 /* For a CONST_DECL, set mode, alignment, and sizes from those of the
3783 type in case this node is used in a reference. */
3784 if (TREE_CODE (decl
) == CONST_DECL
)
3786 DECL_MODE (decl
) = TYPE_MODE (type
);
3787 DECL_ALIGN (decl
) = TYPE_ALIGN (type
);
3788 DECL_SIZE (decl
) = TYPE_SIZE (type
);
3789 DECL_SIZE_UNIT (decl
) = TYPE_SIZE_UNIT (type
);
3793 /* Otherwise, only automatic variables need any expansion done. Static and
3794 external variables, and external functions, will be handled by
3795 `assemble_variable' (called from finish_decl). TYPE_DECL requires
3796 nothing. PARM_DECLs are handled in `assign_parms'. */
3797 if (TREE_CODE (decl
) != VAR_DECL
)
3800 if (TREE_STATIC (decl
) || DECL_EXTERNAL (decl
))
3803 thisblock
= block_stack
;
3805 /* Create the RTL representation for the variable. */
3807 if (type
== error_mark_node
)
3808 SET_DECL_RTL (decl
, gen_rtx_MEM (BLKmode
, const0_rtx
));
3810 else if (DECL_SIZE (decl
) == 0)
3811 /* Variable with incomplete type. */
3814 if (DECL_INITIAL (decl
) == 0)
3815 /* Error message was already done; now avoid a crash. */
3816 x
= gen_rtx_MEM (BLKmode
, const0_rtx
);
3818 /* An initializer is going to decide the size of this array.
3819 Until we know the size, represent its address with a reg. */
3820 x
= gen_rtx_MEM (BLKmode
, gen_reg_rtx (Pmode
));
3822 set_mem_attributes (x
, decl
, 1);
3823 SET_DECL_RTL (decl
, x
);
3825 else if (DECL_MODE (decl
) != BLKmode
3826 /* If -ffloat-store, don't put explicit float vars
3828 && !(flag_float_store
3829 && TREE_CODE (type
) == REAL_TYPE
)
3830 && ! TREE_THIS_VOLATILE (decl
)
3831 && (DECL_REGISTER (decl
) || optimize
)
3832 /* if -fcheck-memory-usage, check all variables. */
3833 && ! current_function_check_memory_usage
)
3835 /* Automatic variable that can go in a register. */
3836 int unsignedp
= TREE_UNSIGNED (type
);
3837 enum machine_mode reg_mode
3838 = promote_mode (type
, DECL_MODE (decl
), &unsignedp
, 0);
3840 SET_DECL_RTL (decl
, gen_reg_rtx (reg_mode
));
3841 mark_user_reg (DECL_RTL (decl
));
3843 if (POINTER_TYPE_P (type
))
3844 mark_reg_pointer (DECL_RTL (decl
),
3845 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl
))));
3847 maybe_set_unchanging (DECL_RTL (decl
), decl
);
3849 /* If something wants our address, try to use ADDRESSOF. */
3850 if (TREE_ADDRESSABLE (decl
))
3851 put_var_into_stack (decl
);
3854 else if (TREE_CODE (DECL_SIZE_UNIT (decl
)) == INTEGER_CST
3855 && ! (flag_stack_check
&& ! STACK_CHECK_BUILTIN
3856 && 0 < compare_tree_int (DECL_SIZE_UNIT (decl
),
3857 STACK_CHECK_MAX_VAR_SIZE
)))
3859 /* Variable of fixed size that goes on the stack. */
3863 /* If we previously made RTL for this decl, it must be an array
3864 whose size was determined by the initializer.
3865 The old address was a register; set that register now
3866 to the proper address. */
3867 if (DECL_RTL_SET_P (decl
))
3869 if (GET_CODE (DECL_RTL (decl
)) != MEM
3870 || GET_CODE (XEXP (DECL_RTL (decl
), 0)) != REG
)
3872 oldaddr
= XEXP (DECL_RTL (decl
), 0);
3876 assign_temp (TREE_TYPE (decl
), 1, 1, 1));
3878 /* Set alignment we actually gave this decl. */
3879 DECL_ALIGN (decl
) = (DECL_MODE (decl
) == BLKmode
? BIGGEST_ALIGNMENT
3880 : GET_MODE_BITSIZE (DECL_MODE (decl
)));
3881 DECL_USER_ALIGN (decl
) = 0;
3885 addr
= force_operand (XEXP (DECL_RTL (decl
), 0), oldaddr
);
3886 if (addr
!= oldaddr
)
3887 emit_move_insn (oldaddr
, addr
);
3891 /* Dynamic-size object: must push space on the stack. */
3893 rtx address
, size
, x
;
3895 /* Record the stack pointer on entry to block, if have
3896 not already done so. */
3897 do_pending_stack_adjust ();
3898 save_stack_pointer ();
3900 /* In function-at-a-time mode, variable_size doesn't expand this,
3902 if (TREE_CODE (type
) == ARRAY_TYPE
&& TYPE_DOMAIN (type
))
3903 expand_expr (TYPE_MAX_VALUE (TYPE_DOMAIN (type
)),
3904 const0_rtx
, VOIDmode
, 0);
3906 /* Compute the variable's size, in bytes. */
3907 size
= expand_expr (DECL_SIZE_UNIT (decl
), NULL_RTX
, VOIDmode
, 0);
3910 /* Allocate space on the stack for the variable. Note that
3911 DECL_ALIGN says how the variable is to be aligned and we
3912 cannot use it to conclude anything about the alignment of
3914 address
= allocate_dynamic_stack_space (size
, NULL_RTX
,
3915 TYPE_ALIGN (TREE_TYPE (decl
)));
3917 /* Reference the variable indirect through that rtx. */
3918 x
= gen_rtx_MEM (DECL_MODE (decl
), address
);
3919 set_mem_attributes (x
, decl
, 1);
3920 SET_DECL_RTL (decl
, x
);
3923 /* Indicate the alignment we actually gave this variable. */
3924 #ifdef STACK_BOUNDARY
3925 DECL_ALIGN (decl
) = STACK_BOUNDARY
;
3927 DECL_ALIGN (decl
) = BIGGEST_ALIGNMENT
;
3929 DECL_USER_ALIGN (decl
) = 0;
3933 /* Emit code to perform the initialization of a declaration DECL. */
3936 expand_decl_init (decl
)
3939 int was_used
= TREE_USED (decl
);
3941 /* If this is a CONST_DECL, we don't have to generate any code, but
3942 if DECL_INITIAL is a constant, call expand_expr to force TREE_CST_RTL
3943 to be set while in the obstack containing the constant. If we don't
3944 do this, we can lose if we have functions nested three deep and the middle
3945 function makes a CONST_DECL whose DECL_INITIAL is a STRING_CST while
3946 the innermost function is the first to expand that STRING_CST. */
3947 if (TREE_CODE (decl
) == CONST_DECL
)
3949 if (DECL_INITIAL (decl
) && TREE_CONSTANT (DECL_INITIAL (decl
)))
3950 expand_expr (DECL_INITIAL (decl
), NULL_RTX
, VOIDmode
,
3951 EXPAND_INITIALIZER
);
3955 if (TREE_STATIC (decl
))
3958 /* Compute and store the initial value now. */
3960 if (DECL_INITIAL (decl
) == error_mark_node
)
3962 enum tree_code code
= TREE_CODE (TREE_TYPE (decl
));
3964 if (code
== INTEGER_TYPE
|| code
== REAL_TYPE
|| code
== ENUMERAL_TYPE
3965 || code
== POINTER_TYPE
|| code
== REFERENCE_TYPE
)
3966 expand_assignment (decl
, convert (TREE_TYPE (decl
), integer_zero_node
),
3970 else if (DECL_INITIAL (decl
) && TREE_CODE (DECL_INITIAL (decl
)) != TREE_LIST
)
3972 emit_line_note (DECL_SOURCE_FILE (decl
), DECL_SOURCE_LINE (decl
));
3973 expand_assignment (decl
, DECL_INITIAL (decl
), 0, 0);
3977 /* Don't let the initialization count as "using" the variable. */
3978 TREE_USED (decl
) = was_used
;
3980 /* Free any temporaries we made while initializing the decl. */
3981 preserve_temp_slots (NULL_RTX
);
3985 /* CLEANUP is an expression to be executed at exit from this binding contour;
3986 for example, in C++, it might call the destructor for this variable.
3988 We wrap CLEANUP in an UNSAVE_EXPR node, so that we can expand the
3989 CLEANUP multiple times, and have the correct semantics. This
3990 happens in exception handling, for gotos, returns, breaks that
3991 leave the current scope.
3993 If CLEANUP is nonzero and DECL is zero, we record a cleanup
3994 that is not associated with any particular variable. */
3997 expand_decl_cleanup (decl
, cleanup
)
4000 struct nesting
*thisblock
;
4002 /* Error if we are not in any block. */
4003 if (cfun
== 0 || block_stack
== 0)
4006 thisblock
= block_stack
;
4008 /* Record the cleanup if there is one. */
4014 tree
*cleanups
= &thisblock
->data
.block
.cleanups
;
4015 int cond_context
= conditional_context ();
4019 rtx flag
= gen_reg_rtx (word_mode
);
4024 emit_move_insn (flag
, const0_rtx
);
4025 set_flag_0
= get_insns ();
4028 thisblock
->data
.block
.last_unconditional_cleanup
4029 = emit_insns_after (set_flag_0
,
4030 thisblock
->data
.block
.last_unconditional_cleanup
);
4032 emit_move_insn (flag
, const1_rtx
);
4034 cond
= build_decl (VAR_DECL
, NULL_TREE
, type_for_mode (word_mode
, 1));
4035 SET_DECL_RTL (cond
, flag
);
4037 /* Conditionalize the cleanup. */
4038 cleanup
= build (COND_EXPR
, void_type_node
,
4039 truthvalue_conversion (cond
),
4040 cleanup
, integer_zero_node
);
4041 cleanup
= fold (cleanup
);
4043 cleanups
= thisblock
->data
.block
.cleanup_ptr
;
4046 cleanup
= unsave_expr (cleanup
);
4048 t
= *cleanups
= tree_cons (decl
, cleanup
, *cleanups
);
4051 /* If this block has a cleanup, it belongs in stack_block_stack. */
4052 stack_block_stack
= thisblock
;
4059 if (! using_eh_for_cleanups_p
)
4060 TREE_ADDRESSABLE (t
) = 1;
4062 expand_eh_region_start ();
4069 thisblock
->data
.block
.last_unconditional_cleanup
4070 = emit_insns_after (seq
,
4071 thisblock
->data
.block
.last_unconditional_cleanup
);
4075 thisblock
->data
.block
.last_unconditional_cleanup
4077 /* When we insert instructions after the last unconditional cleanup,
4078 we don't adjust last_insn. That means that a later add_insn will
4079 clobber the instructions we've just added. The easiest way to
4080 fix this is to just insert another instruction here, so that the
4081 instructions inserted after the last unconditional cleanup are
4082 never the last instruction. */
4083 emit_note (NULL
, NOTE_INSN_DELETED
);
4084 thisblock
->data
.block
.cleanup_ptr
= &thisblock
->data
.block
.cleanups
;
4090 /* DECL is an anonymous union. CLEANUP is a cleanup for DECL.
4091 DECL_ELTS is the list of elements that belong to DECL's type.
4092 In each, the TREE_VALUE is a VAR_DECL, and the TREE_PURPOSE a cleanup. */
4095 expand_anon_union_decl (decl
, cleanup
, decl_elts
)
4096 tree decl
, cleanup
, decl_elts
;
4098 struct nesting
*thisblock
= cfun
== 0 ? 0 : block_stack
;
4102 /* If any of the elements are addressable, so is the entire union. */
4103 for (t
= decl_elts
; t
; t
= TREE_CHAIN (t
))
4104 if (TREE_ADDRESSABLE (TREE_VALUE (t
)))
4106 TREE_ADDRESSABLE (decl
) = 1;
4111 expand_decl_cleanup (decl
, cleanup
);
4112 x
= DECL_RTL (decl
);
4114 /* Go through the elements, assigning RTL to each. */
4115 for (t
= decl_elts
; t
; t
= TREE_CHAIN (t
))
4117 tree decl_elt
= TREE_VALUE (t
);
4118 tree cleanup_elt
= TREE_PURPOSE (t
);
4119 enum machine_mode mode
= TYPE_MODE (TREE_TYPE (decl_elt
));
4121 /* Propagate the union's alignment to the elements. */
4122 DECL_ALIGN (decl_elt
) = DECL_ALIGN (decl
);
4123 DECL_USER_ALIGN (decl_elt
) = DECL_USER_ALIGN (decl
);
4125 /* If the element has BLKmode and the union doesn't, the union is
4126 aligned such that the element doesn't need to have BLKmode, so
4127 change the element's mode to the appropriate one for its size. */
4128 if (mode
== BLKmode
&& DECL_MODE (decl
) != BLKmode
)
4129 DECL_MODE (decl_elt
) = mode
4130 = mode_for_size_tree (DECL_SIZE (decl_elt
), MODE_INT
, 1);
4132 /* (SUBREG (MEM ...)) at RTL generation time is invalid, so we
4133 instead create a new MEM rtx with the proper mode. */
4134 if (GET_CODE (x
) == MEM
)
4136 if (mode
== GET_MODE (x
))
4137 SET_DECL_RTL (decl_elt
, x
);
4139 SET_DECL_RTL (decl_elt
, adjust_address_nv (x
, mode
, 0));
4141 else if (GET_CODE (x
) == REG
)
4143 if (mode
== GET_MODE (x
))
4144 SET_DECL_RTL (decl_elt
, x
);
4146 SET_DECL_RTL (decl_elt
, gen_lowpart_SUBREG (mode
, x
));
4151 /* Record the cleanup if there is one. */
4154 thisblock
->data
.block
.cleanups
4155 = tree_cons (decl_elt
, cleanup_elt
,
4156 thisblock
->data
.block
.cleanups
);
4160 /* Expand a list of cleanups LIST.
4161 Elements may be expressions or may be nested lists.
4163 If DONT_DO is nonnull, then any list-element
4164 whose TREE_PURPOSE matches DONT_DO is omitted.
4165 This is sometimes used to avoid a cleanup associated with
4166 a value that is being returned out of the scope.
4168 If IN_FIXUP is non-zero, we are generating this cleanup for a fixup
4169 goto and handle protection regions specially in that case.
4171 If REACHABLE, we emit code, otherwise just inform the exception handling
4172 code about this finalization. */
4175 expand_cleanups (list
, dont_do
, in_fixup
, reachable
)
4182 for (tail
= list
; tail
; tail
= TREE_CHAIN (tail
))
4183 if (dont_do
== 0 || TREE_PURPOSE (tail
) != dont_do
)
4185 if (TREE_CODE (TREE_VALUE (tail
)) == TREE_LIST
)
4186 expand_cleanups (TREE_VALUE (tail
), dont_do
, in_fixup
, reachable
);
4189 if (! in_fixup
&& using_eh_for_cleanups_p
)
4190 expand_eh_region_end_cleanup (TREE_VALUE (tail
));
4194 /* Cleanups may be run multiple times. For example,
4195 when exiting a binding contour, we expand the
4196 cleanups associated with that contour. When a goto
4197 within that binding contour has a target outside that
4198 contour, it will expand all cleanups from its scope to
4199 the target. Though the cleanups are expanded multiple
4200 times, the control paths are non-overlapping so the
4201 cleanups will not be executed twice. */
4203 /* We may need to protect from outer cleanups. */
4204 if (in_fixup
&& using_eh_for_cleanups_p
)
4206 expand_eh_region_start ();
4208 expand_expr (TREE_VALUE (tail
), const0_rtx
, VOIDmode
, 0);
4210 expand_eh_region_end_fixup (TREE_VALUE (tail
));
4213 expand_expr (TREE_VALUE (tail
), const0_rtx
, VOIDmode
, 0);
4221 /* Mark when the context we are emitting RTL for as a conditional
4222 context, so that any cleanup actions we register with
4223 expand_decl_init will be properly conditionalized when those
4224 cleanup actions are later performed. Must be called before any
4225 expression (tree) is expanded that is within a conditional context. */
4228 start_cleanup_deferral ()
4230 /* block_stack can be NULL if we are inside the parameter list. It is
4231 OK to do nothing, because cleanups aren't possible here. */
4233 ++block_stack
->data
.block
.conditional_code
;
4236 /* Mark the end of a conditional region of code. Because cleanup
4237 deferrals may be nested, we may still be in a conditional region
4238 after we end the currently deferred cleanups, only after we end all
4239 deferred cleanups, are we back in unconditional code. */
4242 end_cleanup_deferral ()
4244 /* block_stack can be NULL if we are inside the parameter list. It is
4245 OK to do nothing, because cleanups aren't possible here. */
4247 --block_stack
->data
.block
.conditional_code
;
4250 /* Move all cleanups from the current block_stack
4251 to the containing block_stack, where they are assumed to
4252 have been created. If anything can cause a temporary to
4253 be created, but not expanded for more than one level of
4254 block_stacks, then this code will have to change. */
4259 struct nesting
*block
= block_stack
;
4260 struct nesting
*outer
= block
->next
;
4262 outer
->data
.block
.cleanups
4263 = chainon (block
->data
.block
.cleanups
,
4264 outer
->data
.block
.cleanups
);
4265 block
->data
.block
.cleanups
= 0;
4269 last_cleanup_this_contour ()
4271 if (block_stack
== 0)
4274 return block_stack
->data
.block
.cleanups
;
4277 /* Return 1 if there are any pending cleanups at this point.
4278 If THIS_CONTOUR is nonzero, check the current contour as well.
4279 Otherwise, look only at the contours that enclose this one. */
4282 any_pending_cleanups (this_contour
)
4285 struct nesting
*block
;
4287 if (cfun
== NULL
|| cfun
->stmt
== NULL
|| block_stack
== 0)
4290 if (this_contour
&& block_stack
->data
.block
.cleanups
!= NULL
)
4292 if (block_stack
->data
.block
.cleanups
== 0
4293 && block_stack
->data
.block
.outer_cleanups
== 0)
4296 for (block
= block_stack
->next
; block
; block
= block
->next
)
4297 if (block
->data
.block
.cleanups
!= 0)
4303 /* Enter a case (Pascal) or switch (C) statement.
4304 Push a block onto case_stack and nesting_stack
4305 to accumulate the case-labels that are seen
4306 and to record the labels generated for the statement.
4308 EXIT_FLAG is nonzero if `exit_something' should exit this case stmt.
4309 Otherwise, this construct is transparent for `exit_something'.
4311 EXPR is the index-expression to be dispatched on.
4312 TYPE is its nominal type. We could simply convert EXPR to this type,
4313 but instead we take short cuts. */
4316 expand_start_case (exit_flag
, expr
, type
, printname
)
4320 const char *printname
;
4322 register struct nesting
*thiscase
= ALLOC_NESTING ();
4324 /* Make an entry on case_stack for the case we are entering. */
4326 thiscase
->next
= case_stack
;
4327 thiscase
->all
= nesting_stack
;
4328 thiscase
->depth
= ++nesting_depth
;
4329 thiscase
->exit_label
= exit_flag
? gen_label_rtx () : 0;
4330 thiscase
->data
.case_stmt
.case_list
= 0;
4331 thiscase
->data
.case_stmt
.index_expr
= expr
;
4332 thiscase
->data
.case_stmt
.nominal_type
= type
;
4333 thiscase
->data
.case_stmt
.default_label
= 0;
4334 thiscase
->data
.case_stmt
.printname
= printname
;
4335 thiscase
->data
.case_stmt
.line_number_status
= force_line_numbers ();
4336 case_stack
= thiscase
;
4337 nesting_stack
= thiscase
;
4339 do_pending_stack_adjust ();
4341 /* Make sure case_stmt.start points to something that won't
4342 need any transformation before expand_end_case. */
4343 if (GET_CODE (get_last_insn ()) != NOTE
)
4344 emit_note (NULL
, NOTE_INSN_DELETED
);
4346 thiscase
->data
.case_stmt
.start
= get_last_insn ();
4348 start_cleanup_deferral ();
4351 /* Start a "dummy case statement" within which case labels are invalid
4352 and are not connected to any larger real case statement.
4353 This can be used if you don't want to let a case statement jump
4354 into the middle of certain kinds of constructs. */
4357 expand_start_case_dummy ()
4359 register struct nesting
*thiscase
= ALLOC_NESTING ();
4361 /* Make an entry on case_stack for the dummy. */
4363 thiscase
->next
= case_stack
;
4364 thiscase
->all
= nesting_stack
;
4365 thiscase
->depth
= ++nesting_depth
;
4366 thiscase
->exit_label
= 0;
4367 thiscase
->data
.case_stmt
.case_list
= 0;
4368 thiscase
->data
.case_stmt
.start
= 0;
4369 thiscase
->data
.case_stmt
.nominal_type
= 0;
4370 thiscase
->data
.case_stmt
.default_label
= 0;
4371 case_stack
= thiscase
;
4372 nesting_stack
= thiscase
;
4373 start_cleanup_deferral ();
4376 /* End a dummy case statement. */
4379 expand_end_case_dummy ()
4381 end_cleanup_deferral ();
4382 POPSTACK (case_stack
);
4385 /* Return the data type of the index-expression
4386 of the innermost case statement, or null if none. */
4389 case_index_expr_type ()
4392 return TREE_TYPE (case_stack
->data
.case_stmt
.index_expr
);
4399 /* If this is the first label, warn if any insns have been emitted. */
4400 if (case_stack
->data
.case_stmt
.line_number_status
>= 0)
4404 restore_line_number_status
4405 (case_stack
->data
.case_stmt
.line_number_status
);
4406 case_stack
->data
.case_stmt
.line_number_status
= -1;
4408 for (insn
= case_stack
->data
.case_stmt
.start
;
4410 insn
= NEXT_INSN (insn
))
4412 if (GET_CODE (insn
) == CODE_LABEL
)
4414 if (GET_CODE (insn
) != NOTE
4415 && (GET_CODE (insn
) != INSN
|| GET_CODE (PATTERN (insn
)) != USE
))
4418 insn
= PREV_INSN (insn
);
4419 while (insn
&& (GET_CODE (insn
) != NOTE
|| NOTE_LINE_NUMBER (insn
) < 0));
4421 /* If insn is zero, then there must have been a syntax error. */
4423 warning_with_file_and_line (NOTE_SOURCE_FILE (insn
),
4424 NOTE_LINE_NUMBER (insn
),
4425 "unreachable code at beginning of %s",
4426 case_stack
->data
.case_stmt
.printname
);
4433 /* Accumulate one case or default label inside a case or switch statement.
4434 VALUE is the value of the case (a null pointer, for a default label).
4435 The function CONVERTER, when applied to arguments T and V,
4436 converts the value V to the type T.
4438 If not currently inside a case or switch statement, return 1 and do
4439 nothing. The caller will print a language-specific error message.
4440 If VALUE is a duplicate or overlaps, return 2 and do nothing
4441 except store the (first) duplicate node in *DUPLICATE.
4442 If VALUE is out of range, return 3 and do nothing.
4443 If we are jumping into the scope of a cleanup or var-sized array, return 5.
4444 Return 0 on success.
4446 Extended to handle range statements. */
4449 pushcase (value
, converter
, label
, duplicate
)
4450 register tree value
;
4451 tree (*converter
) PARAMS ((tree
, tree
));
4452 register tree label
;
4458 /* Fail if not inside a real case statement. */
4459 if (! (case_stack
&& case_stack
->data
.case_stmt
.start
))
4462 if (stack_block_stack
4463 && stack_block_stack
->depth
> case_stack
->depth
)
4466 index_type
= TREE_TYPE (case_stack
->data
.case_stmt
.index_expr
);
4467 nominal_type
= case_stack
->data
.case_stmt
.nominal_type
;
4469 /* If the index is erroneous, avoid more problems: pretend to succeed. */
4470 if (index_type
== error_mark_node
)
4473 /* Convert VALUE to the type in which the comparisons are nominally done. */
4475 value
= (*converter
) (nominal_type
, value
);
4479 /* Fail if this value is out of range for the actual type of the index
4480 (which may be narrower than NOMINAL_TYPE). */
4482 && (TREE_CONSTANT_OVERFLOW (value
)
4483 || ! int_fits_type_p (value
, index_type
)))
4486 return add_case_node (value
, value
, label
, duplicate
);
4489 /* Like pushcase but this case applies to all values between VALUE1 and
4490 VALUE2 (inclusive). If VALUE1 is NULL, the range starts at the lowest
4491 value of the index type and ends at VALUE2. If VALUE2 is NULL, the range
4492 starts at VALUE1 and ends at the highest value of the index type.
4493 If both are NULL, this case applies to all values.
4495 The return value is the same as that of pushcase but there is one
4496 additional error code: 4 means the specified range was empty. */
4499 pushcase_range (value1
, value2
, converter
, label
, duplicate
)
4500 register tree value1
, value2
;
4501 tree (*converter
) PARAMS ((tree
, tree
));
4502 register tree label
;
4508 /* Fail if not inside a real case statement. */
4509 if (! (case_stack
&& case_stack
->data
.case_stmt
.start
))
4512 if (stack_block_stack
4513 && stack_block_stack
->depth
> case_stack
->depth
)
4516 index_type
= TREE_TYPE (case_stack
->data
.case_stmt
.index_expr
);
4517 nominal_type
= case_stack
->data
.case_stmt
.nominal_type
;
4519 /* If the index is erroneous, avoid more problems: pretend to succeed. */
4520 if (index_type
== error_mark_node
)
4525 /* Convert VALUEs to type in which the comparisons are nominally done
4526 and replace any unspecified value with the corresponding bound. */
4528 value1
= TYPE_MIN_VALUE (index_type
);
4530 value2
= TYPE_MAX_VALUE (index_type
);
4532 /* Fail if the range is empty. Do this before any conversion since
4533 we want to allow out-of-range empty ranges. */
4534 if (value2
!= 0 && tree_int_cst_lt (value2
, value1
))
4537 /* If the max was unbounded, use the max of the nominal_type we are
4538 converting to. Do this after the < check above to suppress false
4541 value2
= TYPE_MAX_VALUE (nominal_type
);
4543 value1
= (*converter
) (nominal_type
, value1
);
4544 value2
= (*converter
) (nominal_type
, value2
);
4546 /* Fail if these values are out of range. */
4547 if (TREE_CONSTANT_OVERFLOW (value1
)
4548 || ! int_fits_type_p (value1
, index_type
))
4551 if (TREE_CONSTANT_OVERFLOW (value2
)
4552 || ! int_fits_type_p (value2
, index_type
))
4555 return add_case_node (value1
, value2
, label
, duplicate
);
4558 /* Do the actual insertion of a case label for pushcase and pushcase_range
4559 into case_stack->data.case_stmt.case_list. Use an AVL tree to avoid
4560 slowdown for large switch statements. */
4563 add_case_node (low
, high
, label
, duplicate
)
4568 struct case_node
*p
, **q
, *r
;
4570 /* If there's no HIGH value, then this is not a case range; it's
4571 just a simple case label. But that's just a degenerate case
4576 /* Handle default labels specially. */
4579 if (case_stack
->data
.case_stmt
.default_label
!= 0)
4581 *duplicate
= case_stack
->data
.case_stmt
.default_label
;
4584 case_stack
->data
.case_stmt
.default_label
= label
;
4585 expand_label (label
);
4589 q
= &case_stack
->data
.case_stmt
.case_list
;
4596 /* Keep going past elements distinctly greater than HIGH. */
4597 if (tree_int_cst_lt (high
, p
->low
))
4600 /* or distinctly less than LOW. */
4601 else if (tree_int_cst_lt (p
->high
, low
))
4606 /* We have an overlap; this is an error. */
4607 *duplicate
= p
->code_label
;
4612 /* Add this label to the chain, and succeed. */
4614 r
= (struct case_node
*) xmalloc (sizeof (struct case_node
));
4617 /* If the bounds are equal, turn this into the one-value case. */
4618 if (tree_int_cst_equal (low
, high
))
4623 r
->code_label
= label
;
4624 expand_label (label
);
4634 struct case_node
*s
;
4640 if (! (b
= p
->balance
))
4641 /* Growth propagation from left side. */
4648 if ((p
->left
= s
= r
->right
))
4657 if ((r
->parent
= s
))
4665 case_stack
->data
.case_stmt
.case_list
= r
;
4668 /* r->balance == +1 */
4673 struct case_node
*t
= r
->right
;
4675 if ((p
->left
= s
= t
->right
))
4679 if ((r
->right
= s
= t
->left
))
4693 if ((t
->parent
= s
))
4701 case_stack
->data
.case_stmt
.case_list
= t
;
4708 /* p->balance == +1; growth of left side balances the node. */
4718 if (! (b
= p
->balance
))
4719 /* Growth propagation from right side. */
4727 if ((p
->right
= s
= r
->left
))
4735 if ((r
->parent
= s
))
4744 case_stack
->data
.case_stmt
.case_list
= r
;
4748 /* r->balance == -1 */
4752 struct case_node
*t
= r
->left
;
4754 if ((p
->right
= s
= t
->left
))
4759 if ((r
->left
= s
= t
->right
))
4773 if ((t
->parent
= s
))
4782 case_stack
->data
.case_stmt
.case_list
= t
;
4788 /* p->balance == -1; growth of right side balances the node. */
4801 /* Returns the number of possible values of TYPE.
4802 Returns -1 if the number is unknown, variable, or if the number does not
4803 fit in a HOST_WIDE_INT.
4804 Sets *SPARENESS to 2 if TYPE is an ENUMERAL_TYPE whose values
4805 do not increase monotonically (there may be duplicates);
4806 to 1 if the values increase monotonically, but not always by 1;
4807 otherwise sets it to 0. */
4810 all_cases_count (type
, spareness
)
4815 HOST_WIDE_INT count
, minval
, lastval
;
4819 switch (TREE_CODE (type
))
4826 count
= 1 << BITS_PER_UNIT
;
4831 if (TYPE_MAX_VALUE (type
) != 0
4832 && 0 != (t
= fold (build (MINUS_EXPR
, type
, TYPE_MAX_VALUE (type
),
4833 TYPE_MIN_VALUE (type
))))
4834 && 0 != (t
= fold (build (PLUS_EXPR
, type
, t
,
4835 convert (type
, integer_zero_node
))))
4836 && host_integerp (t
, 1))
4837 count
= tree_low_cst (t
, 1);
4843 /* Don't waste time with enumeral types with huge values. */
4844 if (! host_integerp (TYPE_MIN_VALUE (type
), 0)
4845 || TYPE_MAX_VALUE (type
) == 0
4846 || ! host_integerp (TYPE_MAX_VALUE (type
), 0))
4849 lastval
= minval
= tree_low_cst (TYPE_MIN_VALUE (type
), 0);
4852 for (t
= TYPE_VALUES (type
); t
!= NULL_TREE
; t
= TREE_CHAIN (t
))
4854 HOST_WIDE_INT thisval
= tree_low_cst (TREE_VALUE (t
), 0);
4856 if (*spareness
== 2 || thisval
< lastval
)
4858 else if (thisval
!= minval
+ count
)
4868 #define BITARRAY_TEST(ARRAY, INDEX) \
4869 ((ARRAY)[(unsigned) (INDEX) / HOST_BITS_PER_CHAR]\
4870 & (1 << ((unsigned) (INDEX) % HOST_BITS_PER_CHAR)))
4871 #define BITARRAY_SET(ARRAY, INDEX) \
4872 ((ARRAY)[(unsigned) (INDEX) / HOST_BITS_PER_CHAR]\
4873 |= 1 << ((unsigned) (INDEX) % HOST_BITS_PER_CHAR))
4875 /* Set the elements of the bitstring CASES_SEEN (which has length COUNT),
4876 with the case values we have seen, assuming the case expression
4878 SPARSENESS is as determined by all_cases_count.
4880 The time needed is proportional to COUNT, unless
4881 SPARSENESS is 2, in which case quadratic time is needed. */
4884 mark_seen_cases (type
, cases_seen
, count
, sparseness
)
4886 unsigned char *cases_seen
;
4887 HOST_WIDE_INT count
;
4890 tree next_node_to_try
= NULL_TREE
;
4891 HOST_WIDE_INT next_node_offset
= 0;
4893 register struct case_node
*n
, *root
= case_stack
->data
.case_stmt
.case_list
;
4894 tree val
= make_node (INTEGER_CST
);
4896 TREE_TYPE (val
) = type
;
4900 else if (sparseness
== 2)
4903 unsigned HOST_WIDE_INT xlo
;
4905 /* This less efficient loop is only needed to handle
4906 duplicate case values (multiple enum constants
4907 with the same value). */
4908 TREE_TYPE (val
) = TREE_TYPE (root
->low
);
4909 for (t
= TYPE_VALUES (type
), xlo
= 0; t
!= NULL_TREE
;
4910 t
= TREE_CHAIN (t
), xlo
++)
4912 TREE_INT_CST_LOW (val
) = TREE_INT_CST_LOW (TREE_VALUE (t
));
4913 TREE_INT_CST_HIGH (val
) = TREE_INT_CST_HIGH (TREE_VALUE (t
));
4917 /* Keep going past elements distinctly greater than VAL. */
4918 if (tree_int_cst_lt (val
, n
->low
))
4921 /* or distinctly less than VAL. */
4922 else if (tree_int_cst_lt (n
->high
, val
))
4927 /* We have found a matching range. */
4928 BITARRAY_SET (cases_seen
, xlo
);
4938 case_stack
->data
.case_stmt
.case_list
= root
= case_tree2list (root
, 0);
4940 for (n
= root
; n
; n
= n
->right
)
4942 TREE_INT_CST_LOW (val
) = TREE_INT_CST_LOW (n
->low
);
4943 TREE_INT_CST_HIGH (val
) = TREE_INT_CST_HIGH (n
->low
);
4944 while (! tree_int_cst_lt (n
->high
, val
))
4946 /* Calculate (into xlo) the "offset" of the integer (val).
4947 The element with lowest value has offset 0, the next smallest
4948 element has offset 1, etc. */
4950 unsigned HOST_WIDE_INT xlo
;
4954 if (sparseness
&& TYPE_VALUES (type
) != NULL_TREE
)
4956 /* The TYPE_VALUES will be in increasing order, so
4957 starting searching where we last ended. */
4958 t
= next_node_to_try
;
4959 xlo
= next_node_offset
;
4965 t
= TYPE_VALUES (type
);
4968 if (tree_int_cst_equal (val
, TREE_VALUE (t
)))
4970 next_node_to_try
= TREE_CHAIN (t
);
4971 next_node_offset
= xlo
+ 1;
4976 if (t
== next_node_to_try
)
4985 t
= TYPE_MIN_VALUE (type
);
4987 neg_double (TREE_INT_CST_LOW (t
), TREE_INT_CST_HIGH (t
),
4991 add_double (xlo
, xhi
,
4992 TREE_INT_CST_LOW (val
), TREE_INT_CST_HIGH (val
),
4996 if (xhi
== 0 && xlo
< (unsigned HOST_WIDE_INT
) count
)
4997 BITARRAY_SET (cases_seen
, xlo
);
4999 add_double (TREE_INT_CST_LOW (val
), TREE_INT_CST_HIGH (val
),
5001 &TREE_INT_CST_LOW (val
), &TREE_INT_CST_HIGH (val
));
5007 /* Called when the index of a switch statement is an enumerated type
5008 and there is no default label.
5010 Checks that all enumeration literals are covered by the case
5011 expressions of a switch. Also, warn if there are any extra
5012 switch cases that are *not* elements of the enumerated type.
5014 If all enumeration literals were covered by the case expressions,
5015 turn one of the expressions into the default expression since it should
5016 not be possible to fall through such a switch. */
5019 check_for_full_enumeration_handling (type
)
5022 register struct case_node
*n
;
5023 register tree chain
;
5024 #if 0 /* variable used by 'if 0'ed code below. */
5025 register struct case_node
**l
;
5029 /* True iff the selector type is a numbered set mode. */
5032 /* The number of possible selector values. */
5035 /* For each possible selector value. a one iff it has been matched
5036 by a case value alternative. */
5037 unsigned char *cases_seen
;
5039 /* The allocated size of cases_seen, in chars. */
5040 HOST_WIDE_INT bytes_needed
;
5045 size
= all_cases_count (type
, &sparseness
);
5046 bytes_needed
= (size
+ HOST_BITS_PER_CHAR
) / HOST_BITS_PER_CHAR
;
5048 if (size
> 0 && size
< 600000
5049 /* We deliberately use calloc here, not cmalloc, so that we can suppress
5050 this optimization if we don't have enough memory rather than
5051 aborting, as xmalloc would do. */
5053 (unsigned char *) really_call_calloc (bytes_needed
, 1)) != NULL
)
5056 tree v
= TYPE_VALUES (type
);
5058 /* The time complexity of this code is normally O(N), where
5059 N being the number of members in the enumerated type.
5060 However, if type is a ENUMERAL_TYPE whose values do not
5061 increase monotonically, O(N*log(N)) time may be needed. */
5063 mark_seen_cases (type
, cases_seen
, size
, sparseness
);
5065 for (i
= 0; v
!= NULL_TREE
&& i
< size
; i
++, v
= TREE_CHAIN (v
))
5066 if (BITARRAY_TEST (cases_seen
, i
) == 0)
5067 warning ("enumeration value `%s' not handled in switch",
5068 IDENTIFIER_POINTER (TREE_PURPOSE (v
)));
5073 /* Now we go the other way around; we warn if there are case
5074 expressions that don't correspond to enumerators. This can
5075 occur since C and C++ don't enforce type-checking of
5076 assignments to enumeration variables. */
5078 if (case_stack
->data
.case_stmt
.case_list
5079 && case_stack
->data
.case_stmt
.case_list
->left
)
5080 case_stack
->data
.case_stmt
.case_list
5081 = case_tree2list (case_stack
->data
.case_stmt
.case_list
, 0);
5083 for (n
= case_stack
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5085 for (chain
= TYPE_VALUES (type
);
5086 chain
&& !tree_int_cst_equal (n
->low
, TREE_VALUE (chain
));
5087 chain
= TREE_CHAIN (chain
))
5092 if (TYPE_NAME (type
) == 0)
5093 warning ("case value `%ld' not in enumerated type",
5094 (long) TREE_INT_CST_LOW (n
->low
));
5096 warning ("case value `%ld' not in enumerated type `%s'",
5097 (long) TREE_INT_CST_LOW (n
->low
),
5098 IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type
))
5101 : DECL_NAME (TYPE_NAME (type
))));
5103 if (!tree_int_cst_equal (n
->low
, n
->high
))
5105 for (chain
= TYPE_VALUES (type
);
5106 chain
&& !tree_int_cst_equal (n
->high
, TREE_VALUE (chain
));
5107 chain
= TREE_CHAIN (chain
))
5112 if (TYPE_NAME (type
) == 0)
5113 warning ("case value `%ld' not in enumerated type",
5114 (long) TREE_INT_CST_LOW (n
->high
));
5116 warning ("case value `%ld' not in enumerated type `%s'",
5117 (long) TREE_INT_CST_LOW (n
->high
),
5118 IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type
))
5121 : DECL_NAME (TYPE_NAME (type
))));
5127 /* ??? This optimization is disabled because it causes valid programs to
5128 fail. ANSI C does not guarantee that an expression with enum type
5129 will have a value that is the same as one of the enumeration literals. */
5131 /* If all values were found as case labels, make one of them the default
5132 label. Thus, this switch will never fall through. We arbitrarily pick
5133 the last one to make the default since this is likely the most
5134 efficient choice. */
5138 for (l
= &case_stack
->data
.case_stmt
.case_list
;
5143 case_stack
->data
.case_stmt
.default_label
= (*l
)->code_label
;
5149 /* Free CN, and its children. */
5152 free_case_nodes (cn
)
5157 free_case_nodes (cn
->left
);
5158 free_case_nodes (cn
->right
);
5164 /* Terminate a case (Pascal) or switch (C) statement
5165 in which ORIG_INDEX is the expression to be tested.
5166 Generate the code to test it and jump to the right place. */
5169 expand_end_case (orig_index
)
5172 tree minval
= NULL_TREE
, maxval
= NULL_TREE
, range
= NULL_TREE
, orig_minval
;
5173 rtx default_label
= 0;
5174 register struct case_node
*n
;
5182 register struct nesting
*thiscase
= case_stack
;
5183 tree index_expr
, index_type
;
5186 /* Don't crash due to previous errors. */
5187 if (thiscase
== NULL
)
5190 table_label
= gen_label_rtx ();
5191 index_expr
= thiscase
->data
.case_stmt
.index_expr
;
5192 index_type
= TREE_TYPE (index_expr
);
5193 unsignedp
= TREE_UNSIGNED (index_type
);
5195 do_pending_stack_adjust ();
5197 /* This might get an spurious warning in the presence of a syntax error;
5198 it could be fixed by moving the call to check_seenlabel after the
5199 check for error_mark_node, and copying the code of check_seenlabel that
5200 deals with case_stack->data.case_stmt.line_number_status /
5201 restore_line_number_status in front of the call to end_cleanup_deferral;
5202 However, this might miss some useful warnings in the presence of
5203 non-syntax errors. */
5206 /* An ERROR_MARK occurs for various reasons including invalid data type. */
5207 if (index_type
!= error_mark_node
)
5209 /* If switch expression was an enumerated type, check that all
5210 enumeration literals are covered by the cases.
5211 No sense trying this if there's a default case, however. */
5213 if (!thiscase
->data
.case_stmt
.default_label
5214 && TREE_CODE (TREE_TYPE (orig_index
)) == ENUMERAL_TYPE
5215 && TREE_CODE (index_expr
) != INTEGER_CST
)
5216 check_for_full_enumeration_handling (TREE_TYPE (orig_index
));
5218 /* If we don't have a default-label, create one here,
5219 after the body of the switch. */
5220 if (thiscase
->data
.case_stmt
.default_label
== 0)
5222 thiscase
->data
.case_stmt
.default_label
5223 = build_decl (LABEL_DECL
, NULL_TREE
, NULL_TREE
);
5224 expand_label (thiscase
->data
.case_stmt
.default_label
);
5226 default_label
= label_rtx (thiscase
->data
.case_stmt
.default_label
);
5228 before_case
= get_last_insn ();
5230 if (thiscase
->data
.case_stmt
.case_list
5231 && thiscase
->data
.case_stmt
.case_list
->left
)
5232 thiscase
->data
.case_stmt
.case_list
5233 = case_tree2list (thiscase
->data
.case_stmt
.case_list
, 0);
5235 /* Simplify the case-list before we count it. */
5236 group_case_nodes (thiscase
->data
.case_stmt
.case_list
);
5238 /* Get upper and lower bounds of case values.
5239 Also convert all the case values to the index expr's data type. */
5242 for (n
= thiscase
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5244 /* Check low and high label values are integers. */
5245 if (TREE_CODE (n
->low
) != INTEGER_CST
)
5247 if (TREE_CODE (n
->high
) != INTEGER_CST
)
5250 n
->low
= convert (index_type
, n
->low
);
5251 n
->high
= convert (index_type
, n
->high
);
5253 /* Count the elements and track the largest and smallest
5254 of them (treating them as signed even if they are not). */
5262 if (INT_CST_LT (n
->low
, minval
))
5264 if (INT_CST_LT (maxval
, n
->high
))
5267 /* A range counts double, since it requires two compares. */
5268 if (! tree_int_cst_equal (n
->low
, n
->high
))
5272 orig_minval
= minval
;
5274 /* Compute span of values. */
5276 range
= fold (build (MINUS_EXPR
, index_type
, maxval
, minval
));
5278 end_cleanup_deferral ();
5282 expand_expr (index_expr
, const0_rtx
, VOIDmode
, 0);
5284 emit_jump (default_label
);
5287 /* If range of values is much bigger than number of values,
5288 make a sequence of conditional branches instead of a dispatch.
5289 If the switch-index is a constant, do it this way
5290 because we can optimize it. */
5292 #ifndef CASE_VALUES_THRESHOLD
5294 #define CASE_VALUES_THRESHOLD (HAVE_casesi ? 4 : 5)
5296 /* If machine does not have a case insn that compares the
5297 bounds, this means extra overhead for dispatch tables
5298 which raises the threshold for using them. */
5299 #define CASE_VALUES_THRESHOLD 5
5300 #endif /* HAVE_casesi */
5301 #endif /* CASE_VALUES_THRESHOLD */
5303 else if (count
< CASE_VALUES_THRESHOLD
5304 || compare_tree_int (range
, 10 * count
) > 0
5305 /* RANGE may be signed, and really large ranges will show up
5306 as negative numbers. */
5307 || compare_tree_int (range
, 0) < 0
5308 #ifndef ASM_OUTPUT_ADDR_DIFF_ELT
5311 || TREE_CODE (index_expr
) == INTEGER_CST
5312 /* These will reduce to a constant. */
5313 || (TREE_CODE (index_expr
) == CALL_EXPR
5314 && TREE_CODE (TREE_OPERAND (index_expr
, 0)) == ADDR_EXPR
5315 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (index_expr
, 0), 0)) == FUNCTION_DECL
5316 && DECL_BUILT_IN_CLASS (TREE_OPERAND (TREE_OPERAND (index_expr
, 0), 0)) == BUILT_IN_NORMAL
5317 && DECL_FUNCTION_CODE (TREE_OPERAND (TREE_OPERAND (index_expr
, 0), 0)) == BUILT_IN_CLASSIFY_TYPE
)
5318 || (TREE_CODE (index_expr
) == COMPOUND_EXPR
5319 && TREE_CODE (TREE_OPERAND (index_expr
, 1)) == INTEGER_CST
))
5321 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5323 /* If the index is a short or char that we do not have
5324 an insn to handle comparisons directly, convert it to
5325 a full integer now, rather than letting each comparison
5326 generate the conversion. */
5328 if (GET_MODE_CLASS (GET_MODE (index
)) == MODE_INT
5329 && (cmp_optab
->handlers
[(int) GET_MODE (index
)].insn_code
5330 == CODE_FOR_nothing
))
5332 enum machine_mode wider_mode
;
5333 for (wider_mode
= GET_MODE (index
); wider_mode
!= VOIDmode
;
5334 wider_mode
= GET_MODE_WIDER_MODE (wider_mode
))
5335 if (cmp_optab
->handlers
[(int) wider_mode
].insn_code
5336 != CODE_FOR_nothing
)
5338 index
= convert_to_mode (wider_mode
, index
, unsignedp
);
5344 do_pending_stack_adjust ();
5346 index
= protect_from_queue (index
, 0);
5347 if (GET_CODE (index
) == MEM
)
5348 index
= copy_to_reg (index
);
5349 if (GET_CODE (index
) == CONST_INT
5350 || TREE_CODE (index_expr
) == INTEGER_CST
)
5352 /* Make a tree node with the proper constant value
5353 if we don't already have one. */
5354 if (TREE_CODE (index_expr
) != INTEGER_CST
)
5357 = build_int_2 (INTVAL (index
),
5358 unsignedp
|| INTVAL (index
) >= 0 ? 0 : -1);
5359 index_expr
= convert (index_type
, index_expr
);
5362 /* For constant index expressions we need only
5363 issue a unconditional branch to the appropriate
5364 target code. The job of removing any unreachable
5365 code is left to the optimisation phase if the
5366 "-O" option is specified. */
5367 for (n
= thiscase
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5368 if (! tree_int_cst_lt (index_expr
, n
->low
)
5369 && ! tree_int_cst_lt (n
->high
, index_expr
))
5373 emit_jump (label_rtx (n
->code_label
));
5375 emit_jump (default_label
);
5379 /* If the index expression is not constant we generate
5380 a binary decision tree to select the appropriate
5381 target code. This is done as follows:
5383 The list of cases is rearranged into a binary tree,
5384 nearly optimal assuming equal probability for each case.
5386 The tree is transformed into RTL, eliminating
5387 redundant test conditions at the same time.
5389 If program flow could reach the end of the
5390 decision tree an unconditional jump to the
5391 default code is emitted. */
5394 = (TREE_CODE (TREE_TYPE (orig_index
)) != ENUMERAL_TYPE
5395 && estimate_case_costs (thiscase
->data
.case_stmt
.case_list
));
5396 balance_case_nodes (&thiscase
->data
.case_stmt
.case_list
, NULL
);
5397 emit_case_nodes (index
, thiscase
->data
.case_stmt
.case_list
,
5398 default_label
, index_type
);
5399 emit_jump_if_reachable (default_label
);
5408 enum machine_mode index_mode
= SImode
;
5409 int index_bits
= GET_MODE_BITSIZE (index_mode
);
5411 enum machine_mode op_mode
;
5413 /* Convert the index to SImode. */
5414 if (GET_MODE_BITSIZE (TYPE_MODE (index_type
))
5415 > GET_MODE_BITSIZE (index_mode
))
5417 enum machine_mode omode
= TYPE_MODE (index_type
);
5418 rtx rangertx
= expand_expr (range
, NULL_RTX
, VOIDmode
, 0);
5420 /* We must handle the endpoints in the original mode. */
5421 index_expr
= build (MINUS_EXPR
, index_type
,
5422 index_expr
, minval
);
5423 minval
= integer_zero_node
;
5424 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5425 emit_cmp_and_jump_insns (rangertx
, index
, LTU
, NULL_RTX
,
5426 omode
, 1, 0, default_label
);
5427 /* Now we can safely truncate. */
5428 index
= convert_to_mode (index_mode
, index
, 0);
5432 if (TYPE_MODE (index_type
) != index_mode
)
5434 index_expr
= convert (type_for_size (index_bits
, 0),
5436 index_type
= TREE_TYPE (index_expr
);
5439 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5442 index
= protect_from_queue (index
, 0);
5443 do_pending_stack_adjust ();
5445 op_mode
= insn_data
[(int) CODE_FOR_casesi
].operand
[0].mode
;
5446 if (! (*insn_data
[(int) CODE_FOR_casesi
].operand
[0].predicate
)
5448 index
= copy_to_mode_reg (op_mode
, index
);
5450 op1
= expand_expr (minval
, NULL_RTX
, VOIDmode
, 0);
5452 op_mode
= insn_data
[(int) CODE_FOR_casesi
].operand
[1].mode
;
5453 op1
= convert_modes (op_mode
, TYPE_MODE (TREE_TYPE (minval
)),
5454 op1
, TREE_UNSIGNED (TREE_TYPE (minval
)));
5455 if (! (*insn_data
[(int) CODE_FOR_casesi
].operand
[1].predicate
)
5457 op1
= copy_to_mode_reg (op_mode
, op1
);
5459 op2
= expand_expr (range
, NULL_RTX
, VOIDmode
, 0);
5461 op_mode
= insn_data
[(int) CODE_FOR_casesi
].operand
[2].mode
;
5462 op2
= convert_modes (op_mode
, TYPE_MODE (TREE_TYPE (range
)),
5463 op2
, TREE_UNSIGNED (TREE_TYPE (range
)));
5464 if (! (*insn_data
[(int) CODE_FOR_casesi
].operand
[2].predicate
)
5466 op2
= copy_to_mode_reg (op_mode
, op2
);
5468 emit_jump_insn (gen_casesi (index
, op1
, op2
,
5469 table_label
, default_label
));
5473 #ifdef HAVE_tablejump
5474 if (! win
&& HAVE_tablejump
)
5476 index_type
= thiscase
->data
.case_stmt
.nominal_type
;
5477 index_expr
= fold (build (MINUS_EXPR
, index_type
,
5478 convert (index_type
, index_expr
),
5479 convert (index_type
, minval
)));
5480 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5482 index
= protect_from_queue (index
, 0);
5483 do_pending_stack_adjust ();
5485 do_tablejump (index
, TYPE_MODE (index_type
),
5486 convert_modes (TYPE_MODE (index_type
),
5487 TYPE_MODE (TREE_TYPE (range
)),
5488 expand_expr (range
, NULL_RTX
,
5490 TREE_UNSIGNED (TREE_TYPE (range
))),
5491 table_label
, default_label
);
5498 /* Get table of labels to jump to, in order of case index. */
5500 ncases
= TREE_INT_CST_LOW (range
) + 1;
5501 labelvec
= (rtx
*) alloca (ncases
* sizeof (rtx
));
5502 memset ((char *) labelvec
, 0, ncases
* sizeof (rtx
));
5504 for (n
= thiscase
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5506 register HOST_WIDE_INT i
5507 = TREE_INT_CST_LOW (n
->low
) - TREE_INT_CST_LOW (orig_minval
);
5512 = gen_rtx_LABEL_REF (Pmode
, label_rtx (n
->code_label
));
5513 if (i
+ TREE_INT_CST_LOW (orig_minval
)
5514 == TREE_INT_CST_LOW (n
->high
))
5520 /* Fill in the gaps with the default. */
5521 for (i
= 0; i
< ncases
; i
++)
5522 if (labelvec
[i
] == 0)
5523 labelvec
[i
] = gen_rtx_LABEL_REF (Pmode
, default_label
);
5525 /* Output the table */
5526 emit_label (table_label
);
5528 if (CASE_VECTOR_PC_RELATIVE
|| flag_pic
)
5529 emit_jump_insn (gen_rtx_ADDR_DIFF_VEC (CASE_VECTOR_MODE
,
5530 gen_rtx_LABEL_REF (Pmode
, table_label
),
5531 gen_rtvec_v (ncases
, labelvec
),
5532 const0_rtx
, const0_rtx
));
5534 emit_jump_insn (gen_rtx_ADDR_VEC (CASE_VECTOR_MODE
,
5535 gen_rtvec_v (ncases
, labelvec
)));
5537 /* If the case insn drops through the table,
5538 after the table we must jump to the default-label.
5539 Otherwise record no drop-through after the table. */
5540 #ifdef CASE_DROPS_THROUGH
5541 emit_jump (default_label
);
5547 before_case
= squeeze_notes (NEXT_INSN (before_case
), get_last_insn ());
5548 reorder_insns (before_case
, get_last_insn (),
5549 thiscase
->data
.case_stmt
.start
);
5552 end_cleanup_deferral ();
5554 if (thiscase
->exit_label
)
5555 emit_label (thiscase
->exit_label
);
5557 free_case_nodes (case_stack
->data
.case_stmt
.case_list
);
5558 POPSTACK (case_stack
);
5563 /* Convert the tree NODE into a list linked by the right field, with the left
5564 field zeroed. RIGHT is used for recursion; it is a list to be placed
5565 rightmost in the resulting list. */
5567 static struct case_node
*
5568 case_tree2list (node
, right
)
5569 struct case_node
*node
, *right
;
5571 struct case_node
*left
;
5574 right
= case_tree2list (node
->right
, right
);
5576 node
->right
= right
;
5577 if ((left
= node
->left
))
5580 return case_tree2list (left
, node
);
5586 /* Generate code to jump to LABEL if OP1 and OP2 are equal. */
5589 do_jump_if_equal (op1
, op2
, label
, unsignedp
)
5590 rtx op1
, op2
, label
;
5593 if (GET_CODE (op1
) == CONST_INT
5594 && GET_CODE (op2
) == CONST_INT
)
5596 if (INTVAL (op1
) == INTVAL (op2
))
5601 enum machine_mode mode
= GET_MODE (op1
);
5602 if (mode
== VOIDmode
)
5603 mode
= GET_MODE (op2
);
5604 emit_cmp_and_jump_insns (op1
, op2
, EQ
, NULL_RTX
, mode
, unsignedp
,
5609 /* Not all case values are encountered equally. This function
5610 uses a heuristic to weight case labels, in cases where that
5611 looks like a reasonable thing to do.
5613 Right now, all we try to guess is text, and we establish the
5616 chars above space: 16
5625 If we find any cases in the switch that are not either -1 or in the range
5626 of valid ASCII characters, or are control characters other than those
5627 commonly used with "\", don't treat this switch scanning text.
5629 Return 1 if these nodes are suitable for cost estimation, otherwise
5633 estimate_case_costs (node
)
5636 tree min_ascii
= integer_minus_one_node
;
5637 tree max_ascii
= convert (TREE_TYPE (node
->high
), build_int_2 (127, 0));
5641 /* If we haven't already made the cost table, make it now. Note that the
5642 lower bound of the table is -1, not zero. */
5644 if (! cost_table_initialized
)
5646 cost_table_initialized
= 1;
5648 for (i
= 0; i
< 128; i
++)
5651 COST_TABLE (i
) = 16;
5652 else if (ISPUNCT (i
))
5654 else if (ISCNTRL (i
))
5655 COST_TABLE (i
) = -1;
5658 COST_TABLE (' ') = 8;
5659 COST_TABLE ('\t') = 4;
5660 COST_TABLE ('\0') = 4;
5661 COST_TABLE ('\n') = 2;
5662 COST_TABLE ('\f') = 1;
5663 COST_TABLE ('\v') = 1;
5664 COST_TABLE ('\b') = 1;
5667 /* See if all the case expressions look like text. It is text if the
5668 constant is >= -1 and the highest constant is <= 127. Do all comparisons
5669 as signed arithmetic since we don't want to ever access cost_table with a
5670 value less than -1. Also check that none of the constants in a range
5671 are strange control characters. */
5673 for (n
= node
; n
; n
= n
->right
)
5675 if ((INT_CST_LT (n
->low
, min_ascii
)) || INT_CST_LT (max_ascii
, n
->high
))
5678 for (i
= (HOST_WIDE_INT
) TREE_INT_CST_LOW (n
->low
);
5679 i
<= (HOST_WIDE_INT
) TREE_INT_CST_LOW (n
->high
); i
++)
5680 if (COST_TABLE (i
) < 0)
5684 /* All interesting values are within the range of interesting
5685 ASCII characters. */
5689 /* Scan an ordered list of case nodes
5690 combining those with consecutive values or ranges.
5692 Eg. three separate entries 1: 2: 3: become one entry 1..3: */
5695 group_case_nodes (head
)
5698 case_node_ptr node
= head
;
5702 rtx lb
= next_real_insn (label_rtx (node
->code_label
));
5704 case_node_ptr np
= node
;
5706 /* Try to group the successors of NODE with NODE. */
5707 while (((np
= np
->right
) != 0)
5708 /* Do they jump to the same place? */
5709 && ((lb2
= next_real_insn (label_rtx (np
->code_label
))) == lb
5710 || (lb
!= 0 && lb2
!= 0
5711 && simplejump_p (lb
)
5712 && simplejump_p (lb2
)
5713 && rtx_equal_p (SET_SRC (PATTERN (lb
)),
5714 SET_SRC (PATTERN (lb2
)))))
5715 /* Are their ranges consecutive? */
5716 && tree_int_cst_equal (np
->low
,
5717 fold (build (PLUS_EXPR
,
5718 TREE_TYPE (node
->high
),
5721 /* An overflow is not consecutive. */
5722 && tree_int_cst_lt (node
->high
,
5723 fold (build (PLUS_EXPR
,
5724 TREE_TYPE (node
->high
),
5726 integer_one_node
))))
5728 node
->high
= np
->high
;
5730 /* NP is the first node after NODE which can't be grouped with it.
5731 Delete the nodes in between, and move on to that node. */
5737 /* Take an ordered list of case nodes
5738 and transform them into a near optimal binary tree,
5739 on the assumption that any target code selection value is as
5740 likely as any other.
5742 The transformation is performed by splitting the ordered
5743 list into two equal sections plus a pivot. The parts are
5744 then attached to the pivot as left and right branches. Each
5745 branch is then transformed recursively. */
5748 balance_case_nodes (head
, parent
)
5749 case_node_ptr
*head
;
5750 case_node_ptr parent
;
5752 register case_node_ptr np
;
5760 register case_node_ptr
*npp
;
5763 /* Count the number of entries on branch. Also count the ranges. */
5767 if (!tree_int_cst_equal (np
->low
, np
->high
))
5771 cost
+= COST_TABLE (TREE_INT_CST_LOW (np
->high
));
5775 cost
+= COST_TABLE (TREE_INT_CST_LOW (np
->low
));
5783 /* Split this list if it is long enough for that to help. */
5788 /* Find the place in the list that bisects the list's total cost,
5789 Here I gets half the total cost. */
5794 /* Skip nodes while their cost does not reach that amount. */
5795 if (!tree_int_cst_equal ((*npp
)->low
, (*npp
)->high
))
5796 i
-= COST_TABLE (TREE_INT_CST_LOW ((*npp
)->high
));
5797 i
-= COST_TABLE (TREE_INT_CST_LOW ((*npp
)->low
));
5800 npp
= &(*npp
)->right
;
5805 /* Leave this branch lopsided, but optimize left-hand
5806 side and fill in `parent' fields for right-hand side. */
5808 np
->parent
= parent
;
5809 balance_case_nodes (&np
->left
, np
);
5810 for (; np
->right
; np
= np
->right
)
5811 np
->right
->parent
= np
;
5815 /* If there are just three nodes, split at the middle one. */
5817 npp
= &(*npp
)->right
;
5820 /* Find the place in the list that bisects the list's total cost,
5821 where ranges count as 2.
5822 Here I gets half the total cost. */
5823 i
= (i
+ ranges
+ 1) / 2;
5826 /* Skip nodes while their cost does not reach that amount. */
5827 if (!tree_int_cst_equal ((*npp
)->low
, (*npp
)->high
))
5832 npp
= &(*npp
)->right
;
5837 np
->parent
= parent
;
5840 /* Optimize each of the two split parts. */
5841 balance_case_nodes (&np
->left
, np
);
5842 balance_case_nodes (&np
->right
, np
);
5846 /* Else leave this branch as one level,
5847 but fill in `parent' fields. */
5849 np
->parent
= parent
;
5850 for (; np
->right
; np
= np
->right
)
5851 np
->right
->parent
= np
;
5856 /* Search the parent sections of the case node tree
5857 to see if a test for the lower bound of NODE would be redundant.
5858 INDEX_TYPE is the type of the index expression.
5860 The instructions to generate the case decision tree are
5861 output in the same order as nodes are processed so it is
5862 known that if a parent node checks the range of the current
5863 node minus one that the current node is bounded at its lower
5864 span. Thus the test would be redundant. */
5867 node_has_low_bound (node
, index_type
)
5872 case_node_ptr pnode
;
5874 /* If the lower bound of this node is the lowest value in the index type,
5875 we need not test it. */
5877 if (tree_int_cst_equal (node
->low
, TYPE_MIN_VALUE (index_type
)))
5880 /* If this node has a left branch, the value at the left must be less
5881 than that at this node, so it cannot be bounded at the bottom and
5882 we need not bother testing any further. */
5887 low_minus_one
= fold (build (MINUS_EXPR
, TREE_TYPE (node
->low
),
5888 node
->low
, integer_one_node
));
5890 /* If the subtraction above overflowed, we can't verify anything.
5891 Otherwise, look for a parent that tests our value - 1. */
5893 if (! tree_int_cst_lt (low_minus_one
, node
->low
))
5896 for (pnode
= node
->parent
; pnode
; pnode
= pnode
->parent
)
5897 if (tree_int_cst_equal (low_minus_one
, pnode
->high
))
5903 /* Search the parent sections of the case node tree
5904 to see if a test for the upper bound of NODE would be redundant.
5905 INDEX_TYPE is the type of the index expression.
5907 The instructions to generate the case decision tree are
5908 output in the same order as nodes are processed so it is
5909 known that if a parent node checks the range of the current
5910 node plus one that the current node is bounded at its upper
5911 span. Thus the test would be redundant. */
5914 node_has_high_bound (node
, index_type
)
5919 case_node_ptr pnode
;
5921 /* If there is no upper bound, obviously no test is needed. */
5923 if (TYPE_MAX_VALUE (index_type
) == NULL
)
5926 /* If the upper bound of this node is the highest value in the type
5927 of the index expression, we need not test against it. */
5929 if (tree_int_cst_equal (node
->high
, TYPE_MAX_VALUE (index_type
)))
5932 /* If this node has a right branch, the value at the right must be greater
5933 than that at this node, so it cannot be bounded at the top and
5934 we need not bother testing any further. */
5939 high_plus_one
= fold (build (PLUS_EXPR
, TREE_TYPE (node
->high
),
5940 node
->high
, integer_one_node
));
5942 /* If the addition above overflowed, we can't verify anything.
5943 Otherwise, look for a parent that tests our value + 1. */
5945 if (! tree_int_cst_lt (node
->high
, high_plus_one
))
5948 for (pnode
= node
->parent
; pnode
; pnode
= pnode
->parent
)
5949 if (tree_int_cst_equal (high_plus_one
, pnode
->low
))
5955 /* Search the parent sections of the
5956 case node tree to see if both tests for the upper and lower
5957 bounds of NODE would be redundant. */
5960 node_is_bounded (node
, index_type
)
5964 return (node_has_low_bound (node
, index_type
)
5965 && node_has_high_bound (node
, index_type
));
5968 /* Emit an unconditional jump to LABEL unless it would be dead code. */
5971 emit_jump_if_reachable (label
)
5974 if (GET_CODE (get_last_insn ()) != BARRIER
)
5978 /* Emit step-by-step code to select a case for the value of INDEX.
5979 The thus generated decision tree follows the form of the
5980 case-node binary tree NODE, whose nodes represent test conditions.
5981 INDEX_TYPE is the type of the index of the switch.
5983 Care is taken to prune redundant tests from the decision tree
5984 by detecting any boundary conditions already checked by
5985 emitted rtx. (See node_has_high_bound, node_has_low_bound
5986 and node_is_bounded, above.)
5988 Where the test conditions can be shown to be redundant we emit
5989 an unconditional jump to the target code. As a further
5990 optimization, the subordinates of a tree node are examined to
5991 check for bounded nodes. In this case conditional and/or
5992 unconditional jumps as a result of the boundary check for the
5993 current node are arranged to target the subordinates associated
5994 code for out of bound conditions on the current node.
5996 We can assume that when control reaches the code generated here,
5997 the index value has already been compared with the parents
5998 of this node, and determined to be on the same side of each parent
5999 as this node is. Thus, if this node tests for the value 51,
6000 and a parent tested for 52, we don't need to consider
6001 the possibility of a value greater than 51. If another parent
6002 tests for the value 50, then this node need not test anything. */
6005 emit_case_nodes (index
, node
, default_label
, index_type
)
6011 /* If INDEX has an unsigned type, we must make unsigned branches. */
6012 int unsignedp
= TREE_UNSIGNED (index_type
);
6013 enum machine_mode mode
= GET_MODE (index
);
6014 enum machine_mode imode
= TYPE_MODE (index_type
);
6016 /* See if our parents have already tested everything for us.
6017 If they have, emit an unconditional jump for this node. */
6018 if (node_is_bounded (node
, index_type
))
6019 emit_jump (label_rtx (node
->code_label
));
6021 else if (tree_int_cst_equal (node
->low
, node
->high
))
6023 /* Node is single valued. First see if the index expression matches
6024 this node and then check our children, if any. */
6026 do_jump_if_equal (index
,
6027 convert_modes (mode
, imode
,
6028 expand_expr (node
->low
, NULL_RTX
,
6031 label_rtx (node
->code_label
), unsignedp
);
6033 if (node
->right
!= 0 && node
->left
!= 0)
6035 /* This node has children on both sides.
6036 Dispatch to one side or the other
6037 by comparing the index value with this node's value.
6038 If one subtree is bounded, check that one first,
6039 so we can avoid real branches in the tree. */
6041 if (node_is_bounded (node
->right
, index_type
))
6043 emit_cmp_and_jump_insns (index
,
6046 expand_expr (node
->high
, NULL_RTX
,
6049 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6050 label_rtx (node
->right
->code_label
));
6051 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6054 else if (node_is_bounded (node
->left
, index_type
))
6056 emit_cmp_and_jump_insns (index
,
6059 expand_expr (node
->high
, NULL_RTX
,
6062 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6063 label_rtx (node
->left
->code_label
));
6064 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6069 /* Neither node is bounded. First distinguish the two sides;
6070 then emit the code for one side at a time. */
6072 tree test_label
= build_decl (LABEL_DECL
, NULL_TREE
, NULL_TREE
);
6074 /* See if the value is on the right. */
6075 emit_cmp_and_jump_insns (index
,
6078 expand_expr (node
->high
, NULL_RTX
,
6081 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6082 label_rtx (test_label
));
6084 /* Value must be on the left.
6085 Handle the left-hand subtree. */
6086 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6087 /* If left-hand subtree does nothing,
6089 emit_jump_if_reachable (default_label
);
6091 /* Code branches here for the right-hand subtree. */
6092 expand_label (test_label
);
6093 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6097 else if (node
->right
!= 0 && node
->left
== 0)
6099 /* Here we have a right child but no left so we issue conditional
6100 branch to default and process the right child.
6102 Omit the conditional branch to default if we it avoid only one
6103 right child; it costs too much space to save so little time. */
6105 if (node
->right
->right
|| node
->right
->left
6106 || !tree_int_cst_equal (node
->right
->low
, node
->right
->high
))
6108 if (!node_has_low_bound (node
, index_type
))
6110 emit_cmp_and_jump_insns (index
,
6113 expand_expr (node
->high
, NULL_RTX
,
6116 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6120 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6123 /* We cannot process node->right normally
6124 since we haven't ruled out the numbers less than
6125 this node's value. So handle node->right explicitly. */
6126 do_jump_if_equal (index
,
6129 expand_expr (node
->right
->low
, NULL_RTX
,
6132 label_rtx (node
->right
->code_label
), unsignedp
);
6135 else if (node
->right
== 0 && node
->left
!= 0)
6137 /* Just one subtree, on the left. */
6139 #if 0 /* The following code and comment were formerly part
6140 of the condition here, but they didn't work
6141 and I don't understand what the idea was. -- rms. */
6142 /* If our "most probable entry" is less probable
6143 than the default label, emit a jump to
6144 the default label using condition codes
6145 already lying around. With no right branch,
6146 a branch-greater-than will get us to the default
6149 && COST_TABLE (TREE_INT_CST_LOW (node
->high
)) < 12)
6152 if (node
->left
->left
|| node
->left
->right
6153 || !tree_int_cst_equal (node
->left
->low
, node
->left
->high
))
6155 if (!node_has_high_bound (node
, index_type
))
6157 emit_cmp_and_jump_insns (index
,
6160 expand_expr (node
->high
, NULL_RTX
,
6163 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6167 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6170 /* We cannot process node->left normally
6171 since we haven't ruled out the numbers less than
6172 this node's value. So handle node->left explicitly. */
6173 do_jump_if_equal (index
,
6176 expand_expr (node
->left
->low
, NULL_RTX
,
6179 label_rtx (node
->left
->code_label
), unsignedp
);
6184 /* Node is a range. These cases are very similar to those for a single
6185 value, except that we do not start by testing whether this node
6186 is the one to branch to. */
6188 if (node
->right
!= 0 && node
->left
!= 0)
6190 /* Node has subtrees on both sides.
6191 If the right-hand subtree is bounded,
6192 test for it first, since we can go straight there.
6193 Otherwise, we need to make a branch in the control structure,
6194 then handle the two subtrees. */
6195 tree test_label
= 0;
6197 if (node_is_bounded (node
->right
, index_type
))
6198 /* Right hand node is fully bounded so we can eliminate any
6199 testing and branch directly to the target code. */
6200 emit_cmp_and_jump_insns (index
,
6203 expand_expr (node
->high
, NULL_RTX
,
6206 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6207 label_rtx (node
->right
->code_label
));
6210 /* Right hand node requires testing.
6211 Branch to a label where we will handle it later. */
6213 test_label
= build_decl (LABEL_DECL
, NULL_TREE
, NULL_TREE
);
6214 emit_cmp_and_jump_insns (index
,
6217 expand_expr (node
->high
, NULL_RTX
,
6220 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6221 label_rtx (test_label
));
6224 /* Value belongs to this node or to the left-hand subtree. */
6226 emit_cmp_and_jump_insns (index
,
6229 expand_expr (node
->low
, NULL_RTX
,
6232 GE
, NULL_RTX
, mode
, unsignedp
, 0,
6233 label_rtx (node
->code_label
));
6235 /* Handle the left-hand subtree. */
6236 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6238 /* If right node had to be handled later, do that now. */
6242 /* If the left-hand subtree fell through,
6243 don't let it fall into the right-hand subtree. */
6244 emit_jump_if_reachable (default_label
);
6246 expand_label (test_label
);
6247 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6251 else if (node
->right
!= 0 && node
->left
== 0)
6253 /* Deal with values to the left of this node,
6254 if they are possible. */
6255 if (!node_has_low_bound (node
, index_type
))
6257 emit_cmp_and_jump_insns (index
,
6260 expand_expr (node
->low
, NULL_RTX
,
6263 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6267 /* Value belongs to this node or to the right-hand subtree. */
6269 emit_cmp_and_jump_insns (index
,
6272 expand_expr (node
->high
, NULL_RTX
,
6275 LE
, NULL_RTX
, mode
, unsignedp
, 0,
6276 label_rtx (node
->code_label
));
6278 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6281 else if (node
->right
== 0 && node
->left
!= 0)
6283 /* Deal with values to the right of this node,
6284 if they are possible. */
6285 if (!node_has_high_bound (node
, index_type
))
6287 emit_cmp_and_jump_insns (index
,
6290 expand_expr (node
->high
, NULL_RTX
,
6293 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6297 /* Value belongs to this node or to the left-hand subtree. */
6299 emit_cmp_and_jump_insns (index
,
6302 expand_expr (node
->low
, NULL_RTX
,
6305 GE
, NULL_RTX
, mode
, unsignedp
, 0,
6306 label_rtx (node
->code_label
));
6308 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6313 /* Node has no children so we check low and high bounds to remove
6314 redundant tests. Only one of the bounds can exist,
6315 since otherwise this node is bounded--a case tested already. */
6316 int high_bound
= node_has_high_bound (node
, index_type
);
6317 int low_bound
= node_has_low_bound (node
, index_type
);
6319 if (!high_bound
&& low_bound
)
6321 emit_cmp_and_jump_insns (index
,
6324 expand_expr (node
->high
, NULL_RTX
,
6327 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6331 else if (!low_bound
&& high_bound
)
6333 emit_cmp_and_jump_insns (index
,
6336 expand_expr (node
->low
, NULL_RTX
,
6339 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6342 else if (!low_bound
&& !high_bound
)
6344 /* Widen LOW and HIGH to the same width as INDEX. */
6345 tree type
= type_for_mode (mode
, unsignedp
);
6346 tree low
= build1 (CONVERT_EXPR
, type
, node
->low
);
6347 tree high
= build1 (CONVERT_EXPR
, type
, node
->high
);
6348 rtx new_index
, new_bound
;
6350 /* Instead of doing two branches, emit one unsigned branch for
6351 (index-low) > (high-low). */
6352 new_index
= expand_binop (mode
, sub_optab
, index
,
6353 expand_expr (low
, NULL_RTX
, mode
, 0),
6354 NULL_RTX
, unsignedp
, OPTAB_WIDEN
);
6355 new_bound
= expand_expr (fold (build (MINUS_EXPR
, type
,
6359 emit_cmp_and_jump_insns (new_index
, new_bound
, GT
, NULL_RTX
,
6360 mode
, 1, 0, default_label
);
6363 emit_jump (label_rtx (node
->code_label
));