1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 88, 89, 92-6, 1997 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 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. */
46 #include "insn-flags.h"
47 #include "insn-config.h"
48 #include "insn-codes.h"
50 #include "hard-reg-set.h"
57 #include "bc-typecd.h"
58 #include "bc-opcode.h"
62 #define obstack_chunk_alloc xmalloc
63 #define obstack_chunk_free free
64 struct obstack stmt_obstack;
66 /* Filename and line number of last line-number note,
67 whether we actually emitted it or not. */
71 /* Nonzero if within a ({...}) grouping, in which case we must
72 always compute a value for each expr-stmt in case it is the last one. */
74 int expr_stmts_for_value;
76 /* Each time we expand an expression-statement,
77 record the expr's type and its RTL value here. */
79 static tree last_expr_type;
80 static rtx last_expr_value;
82 /* Each time we expand the end of a binding contour (in `expand_end_bindings')
83 and we emit a new NOTE_INSN_BLOCK_END note, we save a pointer to it here.
84 This is used by the `remember_end_note' function to record the endpoint
85 of each generated block in its associated BLOCK node. */
87 static rtx last_block_end_note;
89 /* Number of binding contours started so far in this function. */
91 int block_start_count;
93 /* Nonzero if function being compiled needs to
94 return the address of where it has put a structure value. */
96 extern int current_function_returns_pcc_struct;
98 /* Label that will go on parm cleanup code, if any.
99 Jumping to this label runs cleanup code for parameters, if
100 such code must be run. Following this code is the logical return label. */
102 extern rtx cleanup_label;
104 /* Label that will go on function epilogue.
105 Jumping to this label serves as a "return" instruction
106 on machines which require execution of the epilogue on all returns. */
108 extern rtx return_label;
110 /* Offset to end of allocated area of stack frame.
111 If stack grows down, this is the address of the last stack slot allocated.
112 If stack grows up, this is the address for the next slot. */
113 extern int frame_offset;
115 /* Label to jump back to for tail recursion, or 0 if we have
116 not yet needed one for this function. */
117 extern rtx tail_recursion_label;
119 /* Place after which to insert the tail_recursion_label if we need one. */
120 extern rtx tail_recursion_reentry;
122 /* Location at which to save the argument pointer if it will need to be
123 referenced. There are two cases where this is done: if nonlocal gotos
124 exist, or if vars whose is an offset from the argument pointer will be
125 needed by inner routines. */
127 extern rtx arg_pointer_save_area;
129 /* Chain of all RTL_EXPRs that have insns in them. */
130 extern tree rtl_expr_chain;
132 /* Stack allocation level in which temporaries for TARGET_EXPRs live. */
133 extern int target_temp_slot_level;
135 extern int temp_slot_level;
137 /* Functions and data structures for expanding case statements. */
139 /* Case label structure, used to hold info on labels within case
140 statements. We handle "range" labels; for a single-value label
141 as in C, the high and low limits are the same.
143 An AVL tree of case nodes is initially created, and later transformed
144 to a list linked via the RIGHT fields in the nodes. Nodes with
145 higher case values are later in the list.
147 Switch statements can be output in one of two forms. A branch table
148 is used if there are more than a few labels and the labels are dense
149 within the range between the smallest and largest case value. If a
150 branch table is used, no further manipulations are done with the case
153 The alternative to the use of a branch table is to generate a series
154 of compare and jump insns. When that is done, we use the LEFT, RIGHT,
155 and PARENT fields to hold a binary tree. Initially the tree is
156 totally unbalanced, with everything on the right. We balance the tree
157 with nodes on the left having lower case values than the parent
158 and nodes on the right having higher values. We then output the tree
163 struct case_node *left; /* Left son in binary tree */
164 struct case_node *right; /* Right son in binary tree; also node chain */
165 struct case_node *parent; /* Parent of node in binary tree */
166 tree low; /* Lowest index value for this label */
167 tree high; /* Highest index value for this label */
168 tree code_label; /* Label to jump to when node matches */
172 typedef struct case_node case_node;
173 typedef struct case_node *case_node_ptr;
175 /* These are used by estimate_case_costs and balance_case_nodes. */
177 /* This must be a signed type, and non-ANSI compilers lack signed char. */
178 static short *cost_table;
179 static int use_cost_table;
181 /* Stack of control and binding constructs we are currently inside.
183 These constructs begin when you call `expand_start_WHATEVER'
184 and end when you call `expand_end_WHATEVER'. This stack records
185 info about how the construct began that tells the end-function
186 what to do. It also may provide information about the construct
187 to alter the behavior of other constructs within the body.
188 For example, they may affect the behavior of C `break' and `continue'.
190 Each construct gets one `struct nesting' object.
191 All of these objects are chained through the `all' field.
192 `nesting_stack' points to the first object (innermost construct).
193 The position of an entry on `nesting_stack' is in its `depth' field.
195 Each type of construct has its own individual stack.
196 For example, loops have `loop_stack'. Each object points to the
197 next object of the same type through the `next' field.
199 Some constructs are visible to `break' exit-statements and others
200 are not. Which constructs are visible depends on the language.
201 Therefore, the data structure allows each construct to be visible
202 or not, according to the args given when the construct is started.
203 The construct is visible if the `exit_label' field is non-null.
204 In that case, the value should be a CODE_LABEL rtx. */
209 struct nesting *next;
214 /* For conds (if-then and if-then-else statements). */
217 /* Label for the end of the if construct.
218 There is none if EXITFLAG was not set
219 and no `else' has been seen yet. */
221 /* Label for the end of this alternative.
222 This may be the end of the if or the next else/elseif. */
228 /* Label at the top of the loop; place to loop back to. */
230 /* Label at the end of the whole construct. */
232 /* Label before a jump that branches to the end of the whole
233 construct. This is where destructors go if any. */
235 /* Label for `continue' statement to jump to;
236 this is in front of the stepper of the loop. */
239 /* For variable binding contours. */
242 /* Sequence number of this binding contour within the function,
243 in order of entry. */
244 int block_start_count;
245 /* Nonzero => value to restore stack to on exit. Complemented by
246 bc_stack_level (see below) when generating bytecodes. */
248 /* The NOTE that starts this contour.
249 Used by expand_goto to check whether the destination
250 is within each contour or not. */
252 /* Innermost containing binding contour that has a stack level. */
253 struct nesting *innermost_stack_block;
254 /* List of cleanups to be run on exit from this contour.
255 This is a list of expressions to be evaluated.
256 The TREE_PURPOSE of each link is the ..._DECL node
257 which the cleanup pertains to. */
259 /* List of cleanup-lists of blocks containing this block,
260 as they were at the locus where this block appears.
261 There is an element for each containing block,
262 ordered innermost containing block first.
263 The tail of this list can be 0,
264 if all remaining elements would be empty lists.
265 The element's TREE_VALUE is the cleanup-list of that block,
266 which may be null. */
268 /* Chain of labels defined inside this binding contour.
269 For contours that have stack levels or cleanups. */
270 struct label_chain *label_chain;
271 /* Number of function calls seen, as of start of this block. */
272 int function_call_count;
273 /* Bytecode specific: stack level to restore stack to on exit. */
275 /* Nonzero if this is associated with a EH region. */
276 int exception_region;
277 /* The saved target_temp_slot_level from our outer block.
278 We may reset target_temp_slot_level to be the level of
279 this block, if that is done, target_temp_slot_level
280 reverts to the saved target_temp_slot_level at the very
282 int target_temp_slot_level;
283 /* True if we are currently emitting insns in an area of
284 output code that is controlled by a conditional
285 expression. This is used by the cleanup handling code to
286 generate conditional cleanup actions. */
287 int conditional_code;
288 /* A place to move the start of the exception region for any
289 of the conditional cleanups, must be at the end or after
290 the start of the last unconditional cleanup, and before any
291 conditional branch points. */
292 rtx last_unconditional_cleanup;
293 /* When in a conditional context, this is the specific
294 cleanup list associated with last_unconditional_cleanup,
295 where we place the conditionalized cleanups. */
298 /* For switch (C) or case (Pascal) statements,
299 and also for dummies (see `expand_start_case_dummy'). */
302 /* The insn after which the case dispatch should finally
303 be emitted. Zero for a dummy. */
305 /* For bytecodes, the case table is in-lined right in the code.
306 A label is needed for skipping over this block. It is only
307 used when generating bytecodes. */
309 /* A list of case labels; it is first built as an AVL tree.
310 During expand_end_case, this is converted to a list, and may be
311 rearranged into a nearly balanced binary tree. */
312 struct case_node *case_list;
313 /* Label to jump to if no case matches. */
315 /* The expression to be dispatched on. */
317 /* Type that INDEX_EXPR should be converted to. */
319 /* Number of range exprs in case statement. */
321 /* Name of this kind of statement, for warnings. */
323 /* Nonzero if a case label has been seen in this case stmt. */
329 /* Chain of all pending binding contours. */
330 struct nesting *block_stack;
332 /* If any new stacks are added here, add them to POPSTACKS too. */
334 /* Chain of all pending binding contours that restore stack levels
336 struct nesting *stack_block_stack;
338 /* Chain of all pending conditional statements. */
339 struct nesting *cond_stack;
341 /* Chain of all pending loops. */
342 struct nesting *loop_stack;
344 /* Chain of all pending case or switch statements. */
345 struct nesting *case_stack;
347 /* Separate chain including all of the above,
348 chained through the `all' field. */
349 struct nesting *nesting_stack;
351 /* Number of entries on nesting_stack now. */
354 /* Allocate and return a new `struct nesting'. */
356 #define ALLOC_NESTING() \
357 (struct nesting *) obstack_alloc (&stmt_obstack, sizeof (struct nesting))
359 /* Pop the nesting stack element by element until we pop off
360 the element which is at the top of STACK.
361 Update all the other stacks, popping off elements from them
362 as we pop them from nesting_stack. */
364 #define POPSTACK(STACK) \
365 do { struct nesting *target = STACK; \
366 struct nesting *this; \
367 do { this = nesting_stack; \
368 if (loop_stack == this) \
369 loop_stack = loop_stack->next; \
370 if (cond_stack == this) \
371 cond_stack = cond_stack->next; \
372 if (block_stack == this) \
373 block_stack = block_stack->next; \
374 if (stack_block_stack == this) \
375 stack_block_stack = stack_block_stack->next; \
376 if (case_stack == this) \
377 case_stack = case_stack->next; \
378 nesting_depth = nesting_stack->depth - 1; \
379 nesting_stack = this->all; \
380 obstack_free (&stmt_obstack, this); } \
381 while (this != target); } while (0)
383 /* In some cases it is impossible to generate code for a forward goto
384 until the label definition is seen. This happens when it may be necessary
385 for the goto to reset the stack pointer: we don't yet know how to do that.
386 So expand_goto puts an entry on this fixup list.
387 Each time a binding contour that resets the stack is exited,
389 If the target label has now been defined, we can insert the proper code. */
393 /* Points to following fixup. */
394 struct goto_fixup *next;
395 /* Points to the insn before the jump insn.
396 If more code must be inserted, it goes after this insn. */
398 /* The LABEL_DECL that this jump is jumping to, or 0
399 for break, continue or return. */
401 /* The BLOCK for the place where this goto was found. */
403 /* The CODE_LABEL rtx that this is jumping to. */
405 /* Number of binding contours started in current function
406 before the label reference. */
407 int block_start_count;
408 /* The outermost stack level that should be restored for this jump.
409 Each time a binding contour that resets the stack is exited,
410 if the target label is *not* yet defined, this slot is updated. */
412 /* List of lists of cleanup expressions to be run by this goto.
413 There is one element for each block that this goto is within.
414 The tail of this list can be 0,
415 if all remaining elements would be empty.
416 The TREE_VALUE contains the cleanup list of that block as of the
417 time this goto was seen.
418 The TREE_ADDRESSABLE flag is 1 for a block that has been exited. */
419 tree cleanup_list_list;
421 /* Bytecode specific members follow */
423 /* The label that this jump is jumping to, or 0 for break, continue
425 struct bc_label *bc_target;
427 /* The label we use for the fixup patch */
428 struct bc_label *label;
430 /* True (non-0) if fixup has been handled */
433 /* Like stack_level above, except refers to the interpreter stack */
437 static struct goto_fixup *goto_fixup_chain;
439 /* Within any binding contour that must restore a stack level,
440 all labels are recorded with a chain of these structures. */
444 /* Points to following fixup. */
445 struct label_chain *next;
450 /* Non-zero if we are using EH to handle cleanus. */
451 static int using_eh_for_cleanups_p = 0;
454 static void expand_goto_internal PROTO((tree, rtx, rtx));
455 static void bc_expand_goto_internal PROTO((enum bytecode_opcode,
456 struct bc_label *, tree));
457 static int expand_fixup PROTO((tree, rtx, rtx));
458 static void bc_expand_fixup PROTO((enum bytecode_opcode,
459 struct bc_label *, int));
460 static void fixup_gotos PROTO((struct nesting *, rtx, tree,
462 static void bc_fixup_gotos PROTO((struct nesting *, int, tree,
464 static void bc_expand_start_cond PROTO((tree, int));
465 static void bc_expand_end_cond PROTO((void));
466 static void bc_expand_start_else PROTO((void));
467 static void bc_expand_end_loop PROTO((void));
468 static void bc_expand_end_bindings PROTO((tree, int, int));
469 static void bc_expand_decl PROTO((tree, tree));
470 static void bc_expand_variable_local_init PROTO((tree));
471 static void bc_expand_decl_init PROTO((tree));
472 static void expand_null_return_1 PROTO((rtx, int));
473 static void expand_value_return PROTO((rtx));
474 static int tail_recursion_args PROTO((tree, tree));
475 static void expand_cleanups PROTO((tree, tree, int, int));
476 static void bc_expand_start_case PROTO((struct nesting *, tree,
478 static int bc_pushcase PROTO((tree, tree));
479 static void bc_check_for_full_enumeration_handling PROTO((tree));
480 static void bc_expand_end_case PROTO((tree));
481 static void do_jump_if_equal PROTO((rtx, rtx, rtx, int));
482 static int estimate_case_costs PROTO((case_node_ptr));
483 static void group_case_nodes PROTO((case_node_ptr));
484 static void balance_case_nodes PROTO((case_node_ptr *,
486 static int node_has_low_bound PROTO((case_node_ptr, tree));
487 static int node_has_high_bound PROTO((case_node_ptr, tree));
488 static int node_is_bounded PROTO((case_node_ptr, tree));
489 static void emit_jump_if_reachable PROTO((rtx));
490 static void emit_case_nodes PROTO((rtx, case_node_ptr, rtx, tree));
491 static int add_case_node PROTO((tree, tree, tree, tree *));
492 static struct case_node *case_tree2list PROTO((case_node *, case_node *));
494 extern rtx bc_allocate_local ();
495 extern rtx bc_allocate_variable_array ();
498 using_eh_for_cleanups ()
500 using_eh_for_cleanups_p = 1;
506 gcc_obstack_init (&stmt_obstack);
511 init_stmt_for_function ()
513 /* We are not currently within any block, conditional, loop or case. */
515 stack_block_stack = 0;
522 block_start_count = 0;
524 /* No gotos have been expanded yet. */
525 goto_fixup_chain = 0;
527 /* We are not processing a ({...}) grouping. */
528 expr_stmts_for_value = 0;
531 init_eh_for_function ();
538 p->block_stack = block_stack;
539 p->stack_block_stack = stack_block_stack;
540 p->cond_stack = cond_stack;
541 p->loop_stack = loop_stack;
542 p->case_stack = case_stack;
543 p->nesting_stack = nesting_stack;
544 p->nesting_depth = nesting_depth;
545 p->block_start_count = block_start_count;
546 p->last_expr_type = last_expr_type;
547 p->last_expr_value = last_expr_value;
548 p->expr_stmts_for_value = expr_stmts_for_value;
549 p->emit_filename = emit_filename;
550 p->emit_lineno = emit_lineno;
551 p->goto_fixup_chain = goto_fixup_chain;
556 restore_stmt_status (p)
559 block_stack = p->block_stack;
560 stack_block_stack = p->stack_block_stack;
561 cond_stack = p->cond_stack;
562 loop_stack = p->loop_stack;
563 case_stack = p->case_stack;
564 nesting_stack = p->nesting_stack;
565 nesting_depth = p->nesting_depth;
566 block_start_count = p->block_start_count;
567 last_expr_type = p->last_expr_type;
568 last_expr_value = p->last_expr_value;
569 expr_stmts_for_value = p->expr_stmts_for_value;
570 emit_filename = p->emit_filename;
571 emit_lineno = p->emit_lineno;
572 goto_fixup_chain = p->goto_fixup_chain;
573 restore_eh_status (p);
576 /* Emit a no-op instruction. */
583 if (!output_bytecode)
585 last_insn = get_last_insn ();
587 && (GET_CODE (last_insn) == CODE_LABEL
588 || (GET_CODE (last_insn) == NOTE
589 && prev_real_insn (last_insn) == 0)))
590 emit_insn (gen_nop ());
594 /* Return the rtx-label that corresponds to a LABEL_DECL,
595 creating it if necessary. */
601 if (TREE_CODE (label) != LABEL_DECL)
604 if (DECL_RTL (label))
605 return DECL_RTL (label);
607 return DECL_RTL (label) = gen_label_rtx ();
610 /* Add an unconditional jump to LABEL as the next sequential instruction. */
616 do_pending_stack_adjust ();
617 emit_jump_insn (gen_jump (label));
621 /* Emit code to jump to the address
622 specified by the pointer expression EXP. */
625 expand_computed_goto (exp)
630 bc_expand_expr (exp);
631 bc_emit_instruction (jumpP);
635 rtx x = expand_expr (exp, NULL_RTX, VOIDmode, 0);
637 #ifdef POINTERS_EXTEND_UNSIGNED
638 x = convert_memory_address (Pmode, x);
642 /* Be sure the function is executable. */
643 if (flag_check_memory_usage)
644 emit_library_call (chkr_check_exec_libfunc, 1,
645 VOIDmode, 1, x, ptr_mode);
647 do_pending_stack_adjust ();
648 emit_indirect_jump (x);
652 /* Handle goto statements and the labels that they can go to. */
654 /* Specify the location in the RTL code of a label LABEL,
655 which is a LABEL_DECL tree node.
657 This is used for the kind of label that the user can jump to with a
658 goto statement, and for alternatives of a switch or case statement.
659 RTL labels generated for loops and conditionals don't go through here;
660 they are generated directly at the RTL level, by other functions below.
662 Note that this has nothing to do with defining label *names*.
663 Languages vary in how they do that and what that even means. */
669 struct label_chain *p;
673 if (! DECL_RTL (label))
674 DECL_RTL (label) = bc_gen_rtx ((char *) 0, 0, bc_get_bytecode_label ());
675 if (! bc_emit_bytecode_labeldef (BYTECODE_BC_LABEL (DECL_RTL (label))))
676 error ("multiply defined label");
680 do_pending_stack_adjust ();
681 emit_label (label_rtx (label));
682 if (DECL_NAME (label))
683 LABEL_NAME (DECL_RTL (label)) = IDENTIFIER_POINTER (DECL_NAME (label));
685 if (stack_block_stack != 0)
687 p = (struct label_chain *) oballoc (sizeof (struct label_chain));
688 p->next = stack_block_stack->data.block.label_chain;
689 stack_block_stack->data.block.label_chain = p;
694 /* Declare that LABEL (a LABEL_DECL) may be used for nonlocal gotos
695 from nested functions. */
698 declare_nonlocal_label (label)
701 nonlocal_labels = tree_cons (NULL_TREE, label, nonlocal_labels);
702 LABEL_PRESERVE_P (label_rtx (label)) = 1;
703 if (nonlocal_goto_handler_slot == 0)
705 nonlocal_goto_handler_slot
706 = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
707 emit_stack_save (SAVE_NONLOCAL,
708 &nonlocal_goto_stack_level,
709 PREV_INSN (tail_recursion_reentry));
713 /* Generate RTL code for a `goto' statement with target label LABEL.
714 LABEL should be a LABEL_DECL tree node that was or will later be
715 defined with `expand_label'. */
725 expand_goto_internal (label, label_rtx (label), NULL_RTX);
729 /* Check for a nonlocal goto to a containing function. */
730 context = decl_function_context (label);
731 if (context != 0 && context != current_function_decl)
733 struct function *p = find_function_data (context);
734 rtx label_ref = gen_rtx (LABEL_REF, Pmode, label_rtx (label));
737 p->has_nonlocal_label = 1;
738 current_function_has_nonlocal_goto = 1;
739 LABEL_REF_NONLOCAL_P (label_ref) = 1;
741 /* Copy the rtl for the slots so that they won't be shared in
742 case the virtual stack vars register gets instantiated differently
743 in the parent than in the child. */
745 #if HAVE_nonlocal_goto
746 if (HAVE_nonlocal_goto)
747 emit_insn (gen_nonlocal_goto (lookup_static_chain (label),
748 copy_rtx (p->nonlocal_goto_handler_slot),
749 copy_rtx (p->nonlocal_goto_stack_level),
756 /* Restore frame pointer for containing function.
757 This sets the actual hard register used for the frame pointer
758 to the location of the function's incoming static chain info.
759 The non-local goto handler will then adjust it to contain the
760 proper value and reload the argument pointer, if needed. */
761 emit_move_insn (hard_frame_pointer_rtx, lookup_static_chain (label));
763 /* We have now loaded the frame pointer hardware register with
764 the address of that corresponds to the start of the virtual
765 stack vars. So replace virtual_stack_vars_rtx in all
766 addresses we use with stack_pointer_rtx. */
768 /* Get addr of containing function's current nonlocal goto handler,
769 which will do any cleanups and then jump to the label. */
770 addr = copy_rtx (p->nonlocal_goto_handler_slot);
771 temp = copy_to_reg (replace_rtx (addr, virtual_stack_vars_rtx,
772 hard_frame_pointer_rtx));
774 /* Restore the stack pointer. Note this uses fp just restored. */
775 addr = p->nonlocal_goto_stack_level;
777 addr = replace_rtx (copy_rtx (addr),
778 virtual_stack_vars_rtx,
779 hard_frame_pointer_rtx);
781 emit_stack_restore (SAVE_NONLOCAL, addr, NULL_RTX);
783 /* Put in the static chain register the nonlocal label address. */
784 emit_move_insn (static_chain_rtx, label_ref);
785 /* USE of hard_frame_pointer_rtx added for consistency; not clear if
787 emit_insn (gen_rtx (USE, VOIDmode, hard_frame_pointer_rtx));
788 emit_insn (gen_rtx (USE, VOIDmode, stack_pointer_rtx));
789 emit_insn (gen_rtx (USE, VOIDmode, static_chain_rtx));
790 emit_indirect_jump (temp);
794 expand_goto_internal (label, label_rtx (label), NULL_RTX);
797 /* Generate RTL code for a `goto' statement with target label BODY.
798 LABEL should be a LABEL_REF.
799 LAST_INSN, if non-0, is the rtx we should consider as the last
800 insn emitted (for the purposes of cleaning up a return). */
803 expand_goto_internal (body, label, last_insn)
808 struct nesting *block;
811 /* NOTICE! If a bytecode instruction other than `jump' is needed,
812 then the caller has to call bc_expand_goto_internal()
813 directly. This is rather an exceptional case, and there aren't
814 that many places where this is necessary. */
817 expand_goto_internal (body, label, last_insn);
821 if (GET_CODE (label) != CODE_LABEL)
824 /* If label has already been defined, we can tell now
825 whether and how we must alter the stack level. */
827 if (PREV_INSN (label) != 0)
829 /* Find the innermost pending block that contains the label.
830 (Check containment by comparing insn-uids.)
831 Then restore the outermost stack level within that block,
832 and do cleanups of all blocks contained in it. */
833 for (block = block_stack; block; block = block->next)
835 if (INSN_UID (block->data.block.first_insn) < INSN_UID (label))
837 if (block->data.block.stack_level != 0)
838 stack_level = block->data.block.stack_level;
839 /* Execute the cleanups for blocks we are exiting. */
840 if (block->data.block.cleanups != 0)
842 expand_cleanups (block->data.block.cleanups, NULL_TREE, 1, 1);
843 do_pending_stack_adjust ();
849 /* Ensure stack adjust isn't done by emit_jump, as this
850 would clobber the stack pointer. This one should be
851 deleted as dead by flow. */
852 clear_pending_stack_adjust ();
853 do_pending_stack_adjust ();
854 emit_stack_restore (SAVE_BLOCK, stack_level, NULL_RTX);
857 if (body != 0 && DECL_TOO_LATE (body))
858 error ("jump to `%s' invalidly jumps into binding contour",
859 IDENTIFIER_POINTER (DECL_NAME (body)));
861 /* Label not yet defined: may need to put this goto
862 on the fixup list. */
863 else if (! expand_fixup (body, label, last_insn))
865 /* No fixup needed. Record that the label is the target
866 of at least one goto that has no fixup. */
868 TREE_ADDRESSABLE (body) = 1;
874 /* Generate a jump with OPCODE to the given bytecode LABEL which is
875 found within BODY. */
878 bc_expand_goto_internal (opcode, label, body)
879 enum bytecode_opcode opcode;
880 struct bc_label *label;
883 struct nesting *block;
884 int stack_level = -1;
886 /* If the label is defined, adjust the stack as necessary.
887 If it's not defined, we have to push the reference on the
893 /* Find the innermost pending block that contains the label.
894 (Check containment by comparing bytecode uids.) Then restore the
895 outermost stack level within that block. */
897 for (block = block_stack; block; block = block->next)
899 if (BYTECODE_BC_LABEL (block->data.block.first_insn)->uid < label->uid)
901 if (block->data.block.bc_stack_level)
902 stack_level = block->data.block.bc_stack_level;
904 /* Execute the cleanups for blocks we are exiting. */
905 if (block->data.block.cleanups != 0)
907 expand_cleanups (block->data.block.cleanups, NULL_TREE, 1, 1);
908 do_pending_stack_adjust ();
912 /* Restore the stack level. If we need to adjust the stack, we
913 must do so after the jump, since the jump may depend on
914 what's on the stack. Thus, any stack-modifying conditional
915 jumps (these are the only ones that rely on what's on the
916 stack) go into the fixup list. */
919 && stack_depth != stack_level
922 bc_expand_fixup (opcode, label, stack_level);
925 if (stack_level >= 0)
926 bc_adjust_stack (stack_depth - stack_level);
928 if (body && DECL_BIT_FIELD (body))
929 error ("jump to `%s' invalidly jumps into binding contour",
930 IDENTIFIER_POINTER (DECL_NAME (body)));
932 /* Emit immediate jump */
933 bc_emit_bytecode (opcode);
934 bc_emit_bytecode_labelref (label);
936 #ifdef DEBUG_PRINT_CODE
937 fputc ('\n', stderr);
942 /* Put goto in the fixup list */
943 bc_expand_fixup (opcode, label, stack_level);
946 /* Generate if necessary a fixup for a goto
947 whose target label in tree structure (if any) is TREE_LABEL
948 and whose target in rtl is RTL_LABEL.
950 If LAST_INSN is nonzero, we pretend that the jump appears
951 after insn LAST_INSN instead of at the current point in the insn stream.
953 The fixup will be used later to insert insns just before the goto.
954 Those insns will restore the stack level as appropriate for the
955 target label, and will (in the case of C++) also invoke any object
956 destructors which have to be invoked when we exit the scopes which
957 are exited by the goto.
959 Value is nonzero if a fixup is made. */
962 expand_fixup (tree_label, rtl_label, last_insn)
967 struct nesting *block, *end_block;
969 /* See if we can recognize which block the label will be output in.
970 This is possible in some very common cases.
971 If we succeed, set END_BLOCK to that block.
972 Otherwise, set it to 0. */
975 && (rtl_label == cond_stack->data.cond.endif_label
976 || rtl_label == cond_stack->data.cond.next_label))
977 end_block = cond_stack;
978 /* If we are in a loop, recognize certain labels which
979 are likely targets. This reduces the number of fixups
980 we need to create. */
982 && (rtl_label == loop_stack->data.loop.start_label
983 || rtl_label == loop_stack->data.loop.end_label
984 || rtl_label == loop_stack->data.loop.continue_label))
985 end_block = loop_stack;
989 /* Now set END_BLOCK to the binding level to which we will return. */
993 struct nesting *next_block = end_block->all;
996 /* First see if the END_BLOCK is inside the innermost binding level.
997 If so, then no cleanups or stack levels are relevant. */
998 while (next_block && next_block != block)
999 next_block = next_block->all;
1004 /* Otherwise, set END_BLOCK to the innermost binding level
1005 which is outside the relevant control-structure nesting. */
1006 next_block = block_stack->next;
1007 for (block = block_stack; block != end_block; block = block->all)
1008 if (block == next_block)
1009 next_block = next_block->next;
1010 end_block = next_block;
1013 /* Does any containing block have a stack level or cleanups?
1014 If not, no fixup is needed, and that is the normal case
1015 (the only case, for standard C). */
1016 for (block = block_stack; block != end_block; block = block->next)
1017 if (block->data.block.stack_level != 0
1018 || block->data.block.cleanups != 0)
1021 if (block != end_block)
1023 /* Ok, a fixup is needed. Add a fixup to the list of such. */
1024 struct goto_fixup *fixup
1025 = (struct goto_fixup *) oballoc (sizeof (struct goto_fixup));
1026 /* In case an old stack level is restored, make sure that comes
1027 after any pending stack adjust. */
1028 /* ?? If the fixup isn't to come at the present position,
1029 doing the stack adjust here isn't useful. Doing it with our
1030 settings at that location isn't useful either. Let's hope
1033 do_pending_stack_adjust ();
1034 fixup->target = tree_label;
1035 fixup->target_rtl = rtl_label;
1037 /* Create a BLOCK node and a corresponding matched set of
1038 NOTE_INSN_BEGIN_BLOCK and NOTE_INSN_END_BLOCK notes at
1039 this point. The notes will encapsulate any and all fixup
1040 code which we might later insert at this point in the insn
1041 stream. Also, the BLOCK node will be the parent (i.e. the
1042 `SUPERBLOCK') of any other BLOCK nodes which we might create
1043 later on when we are expanding the fixup code. */
1046 register rtx original_before_jump
1047 = last_insn ? last_insn : get_last_insn ();
1051 fixup->before_jump = emit_note (NULL_PTR, NOTE_INSN_BLOCK_BEG);
1052 last_block_end_note = emit_note (NULL_PTR, NOTE_INSN_BLOCK_END);
1053 fixup->context = poplevel (1, 0, 0); /* Create the BLOCK node now! */
1055 emit_insns_after (fixup->before_jump, original_before_jump);
1058 fixup->block_start_count = block_start_count;
1059 fixup->stack_level = 0;
1060 fixup->cleanup_list_list
1061 = ((block->data.block.outer_cleanups
1062 || block->data.block.cleanups)
1063 ? tree_cons (NULL_TREE, block->data.block.cleanups,
1064 block->data.block.outer_cleanups)
1066 fixup->next = goto_fixup_chain;
1067 goto_fixup_chain = fixup;
1074 /* Generate bytecode jump with OPCODE to a fixup routine that links to LABEL.
1075 Make the fixup restore the stack level to STACK_LEVEL. */
1078 bc_expand_fixup (opcode, label, stack_level)
1079 enum bytecode_opcode opcode;
1080 struct bc_label *label;
1083 struct goto_fixup *fixup
1084 = (struct goto_fixup *) oballoc (sizeof (struct goto_fixup));
1086 fixup->label = bc_get_bytecode_label ();
1087 fixup->bc_target = label;
1088 fixup->bc_stack_level = stack_level;
1089 fixup->bc_handled = FALSE;
1091 fixup->next = goto_fixup_chain;
1092 goto_fixup_chain = fixup;
1094 /* Insert a jump to the fixup code */
1095 bc_emit_bytecode (opcode);
1096 bc_emit_bytecode_labelref (fixup->label);
1098 #ifdef DEBUG_PRINT_CODE
1099 fputc ('\n', stderr);
1103 /* Expand any needed fixups in the outputmost binding level of the
1104 function. FIRST_INSN is the first insn in the function. */
1107 expand_fixups (first_insn)
1110 fixup_gotos (NULL_PTR, NULL_RTX, NULL_TREE, first_insn, 0);
1113 /* When exiting a binding contour, process all pending gotos requiring fixups.
1114 THISBLOCK is the structure that describes the block being exited.
1115 STACK_LEVEL is the rtx for the stack level to restore exiting this contour.
1116 CLEANUP_LIST is a list of expressions to evaluate on exiting this contour.
1117 FIRST_INSN is the insn that began this contour.
1119 Gotos that jump out of this contour must restore the
1120 stack level and do the cleanups before actually jumping.
1122 DONT_JUMP_IN nonzero means report error there is a jump into this
1123 contour from before the beginning of the contour.
1124 This is also done if STACK_LEVEL is nonzero. */
1127 fixup_gotos (thisblock, stack_level, cleanup_list, first_insn, dont_jump_in)
1128 struct nesting *thisblock;
1134 register struct goto_fixup *f, *prev;
1136 if (output_bytecode)
1138 /* ??? The second arg is the bc stack level, which is not the same
1139 as STACK_LEVEL. I have no idea what should go here, so I'll
1141 bc_fixup_gotos (thisblock, 0, cleanup_list, first_insn, dont_jump_in);
1145 /* F is the fixup we are considering; PREV is the previous one. */
1146 /* We run this loop in two passes so that cleanups of exited blocks
1147 are run first, and blocks that are exited are marked so
1150 for (prev = 0, f = goto_fixup_chain; f; prev = f, f = f->next)
1152 /* Test for a fixup that is inactive because it is already handled. */
1153 if (f->before_jump == 0)
1155 /* Delete inactive fixup from the chain, if that is easy to do. */
1157 prev->next = f->next;
1159 /* Has this fixup's target label been defined?
1160 If so, we can finalize it. */
1161 else if (PREV_INSN (f->target_rtl) != 0)
1163 register rtx cleanup_insns;
1165 /* Get the first non-label after the label
1166 this goto jumps to. If that's before this scope begins,
1167 we don't have a jump into the scope. */
1168 rtx after_label = f->target_rtl;
1169 while (after_label != 0 && GET_CODE (after_label) == CODE_LABEL)
1170 after_label = NEXT_INSN (after_label);
1172 /* If this fixup jumped into this contour from before the beginning
1173 of this contour, report an error. */
1174 /* ??? Bug: this does not detect jumping in through intermediate
1175 blocks that have stack levels or cleanups.
1176 It detects only a problem with the innermost block
1177 around the label. */
1179 && (dont_jump_in || stack_level || cleanup_list)
1180 /* If AFTER_LABEL is 0, it means the jump goes to the end
1181 of the rtl, which means it jumps into this scope. */
1182 && (after_label == 0
1183 || INSN_UID (first_insn) < INSN_UID (after_label))
1184 && INSN_UID (first_insn) > INSN_UID (f->before_jump)
1185 && ! DECL_ERROR_ISSUED (f->target))
1187 error_with_decl (f->target,
1188 "label `%s' used before containing binding contour");
1189 /* Prevent multiple errors for one label. */
1190 DECL_ERROR_ISSUED (f->target) = 1;
1193 /* We will expand the cleanups into a sequence of their own and
1194 then later on we will attach this new sequence to the insn
1195 stream just ahead of the actual jump insn. */
1199 /* Temporarily restore the lexical context where we will
1200 logically be inserting the fixup code. We do this for the
1201 sake of getting the debugging information right. */
1204 set_block (f->context);
1206 /* Expand the cleanups for blocks this jump exits. */
1207 if (f->cleanup_list_list)
1210 for (lists = f->cleanup_list_list; lists; lists = TREE_CHAIN (lists))
1211 /* Marked elements correspond to blocks that have been closed.
1212 Do their cleanups. */
1213 if (TREE_ADDRESSABLE (lists)
1214 && TREE_VALUE (lists) != 0)
1216 expand_cleanups (TREE_VALUE (lists), NULL_TREE, 1, 1);
1217 /* Pop any pushes done in the cleanups,
1218 in case function is about to return. */
1219 do_pending_stack_adjust ();
1223 /* Restore stack level for the biggest contour that this
1224 jump jumps out of. */
1226 emit_stack_restore (SAVE_BLOCK, f->stack_level, f->before_jump);
1228 /* Finish up the sequence containing the insns which implement the
1229 necessary cleanups, and then attach that whole sequence to the
1230 insn stream just ahead of the actual jump insn. Attaching it
1231 at that point insures that any cleanups which are in fact
1232 implicit C++ object destructions (which must be executed upon
1233 leaving the block) appear (to the debugger) to be taking place
1234 in an area of the generated code where the object(s) being
1235 destructed are still "in scope". */
1237 cleanup_insns = get_insns ();
1241 emit_insns_after (cleanup_insns, f->before_jump);
1248 /* For any still-undefined labels, do the cleanups for this block now.
1249 We must do this now since items in the cleanup list may go out
1250 of scope when the block ends. */
1251 for (prev = 0, f = goto_fixup_chain; f; prev = f, f = f->next)
1252 if (f->before_jump != 0
1253 && PREV_INSN (f->target_rtl) == 0
1254 /* Label has still not appeared. If we are exiting a block with
1255 a stack level to restore, that started before the fixup,
1256 mark this stack level as needing restoration
1257 when the fixup is later finalized. */
1259 /* Note: if THISBLOCK == 0 and we have a label that hasn't appeared, it
1260 means the label is undefined. That's erroneous, but possible. */
1261 && (thisblock->data.block.block_start_count
1262 <= f->block_start_count))
1264 tree lists = f->cleanup_list_list;
1267 for (; lists; lists = TREE_CHAIN (lists))
1268 /* If the following elt. corresponds to our containing block
1269 then the elt. must be for this block. */
1270 if (TREE_CHAIN (lists) == thisblock->data.block.outer_cleanups)
1274 set_block (f->context);
1275 expand_cleanups (TREE_VALUE (lists), NULL_TREE, 1, 1);
1276 do_pending_stack_adjust ();
1277 cleanup_insns = get_insns ();
1280 if (cleanup_insns != 0)
1282 = emit_insns_after (cleanup_insns, f->before_jump);
1284 f->cleanup_list_list = TREE_CHAIN (lists);
1288 f->stack_level = stack_level;
1293 /* When exiting a binding contour, process all pending gotos requiring fixups.
1294 Note: STACK_DEPTH is not altered.
1296 The arguments are currently not used in the bytecode compiler, but we may
1297 need them one day for languages other than C.
1299 THISBLOCK is the structure that describes the block being exited.
1300 STACK_LEVEL is the rtx for the stack level to restore exiting this contour.
1301 CLEANUP_LIST is a list of expressions to evaluate on exiting this contour.
1302 FIRST_INSN is the insn that began this contour.
1304 Gotos that jump out of this contour must restore the
1305 stack level and do the cleanups before actually jumping.
1307 DONT_JUMP_IN nonzero means report error there is a jump into this
1308 contour from before the beginning of the contour.
1309 This is also done if STACK_LEVEL is nonzero. */
1312 bc_fixup_gotos (thisblock, stack_level, cleanup_list, first_insn, dont_jump_in)
1313 struct nesting *thisblock;
1319 register struct goto_fixup *f, *prev;
1320 int saved_stack_depth;
1322 /* F is the fixup we are considering; PREV is the previous one. */
1324 for (prev = 0, f = goto_fixup_chain; f; prev = f, f = f->next)
1326 /* Test for a fixup that is inactive because it is already handled. */
1327 if (f->before_jump == 0)
1329 /* Delete inactive fixup from the chain, if that is easy to do. */
1331 prev->next = f->next;
1334 /* Emit code to restore the stack and continue */
1335 bc_emit_bytecode_labeldef (f->label);
1337 /* Save stack_depth across call, since bc_adjust_stack will alter
1338 the perceived stack depth via the instructions generated. */
1340 if (f->bc_stack_level >= 0)
1342 saved_stack_depth = stack_depth;
1343 bc_adjust_stack (stack_depth - f->bc_stack_level);
1344 stack_depth = saved_stack_depth;
1347 bc_emit_bytecode (jump);
1348 bc_emit_bytecode_labelref (f->bc_target);
1350 #ifdef DEBUG_PRINT_CODE
1351 fputc ('\n', stderr);
1355 goto_fixup_chain = NULL;
1358 /* Generate RTL for an asm statement (explicit assembler code).
1359 BODY is a STRING_CST node containing the assembler code text,
1360 or an ADDR_EXPR containing a STRING_CST. */
1366 if (output_bytecode)
1368 error ("`asm' is invalid when generating bytecode");
1372 if (flag_check_memory_usage)
1374 error ("`asm' cannot be used with `-fcheck-memory-usage'");
1378 if (TREE_CODE (body) == ADDR_EXPR)
1379 body = TREE_OPERAND (body, 0);
1381 emit_insn (gen_rtx (ASM_INPUT, VOIDmode,
1382 TREE_STRING_POINTER (body)));
1386 /* Generate RTL for an asm statement with arguments.
1387 STRING is the instruction template.
1388 OUTPUTS is a list of output arguments (lvalues); INPUTS a list of inputs.
1389 Each output or input has an expression in the TREE_VALUE and
1390 a constraint-string in the TREE_PURPOSE.
1391 CLOBBERS is a list of STRING_CST nodes each naming a hard register
1392 that is clobbered by this insn.
1394 Not all kinds of lvalue that may appear in OUTPUTS can be stored directly.
1395 Some elements of OUTPUTS may be replaced with trees representing temporary
1396 values. The caller should copy those temporary values to the originally
1399 VOL nonzero means the insn is volatile; don't optimize it. */
1402 expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line)
1403 tree string, outputs, inputs, clobbers;
1408 rtvec argvec, constraints;
1410 int ninputs = list_length (inputs);
1411 int noutputs = list_length (outputs);
1416 /* Vector of RTX's of evaluated output operands. */
1417 rtx *output_rtx = (rtx *) alloca (noutputs * sizeof (rtx));
1418 int *inout_opnum = (int *) alloca (noutputs * sizeof (int));
1419 enum machine_mode *inout_mode
1420 = (enum machine_mode *) alloca (noutputs * sizeof (enum machine_mode));
1421 /* The insn we have emitted. */
1424 if (output_bytecode)
1426 error ("`asm' is invalid when generating bytecode");
1430 if (flag_check_memory_usage)
1432 error ("`asm' cannot be used with `-fcheck-memory-usage'");
1436 /* Count the number of meaningful clobbered registers, ignoring what
1437 we would ignore later. */
1439 for (tail = clobbers; tail; tail = TREE_CHAIN (tail))
1441 char *regname = TREE_STRING_POINTER (TREE_VALUE (tail));
1442 i = decode_reg_name (regname);
1443 if (i >= 0 || i == -4)
1446 error ("unknown register name `%s' in `asm'", regname);
1451 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
1453 tree val = TREE_VALUE (tail);
1454 tree type = TREE_TYPE (val);
1457 int found_equal = 0;
1461 /* If there's an erroneous arg, emit no insn. */
1462 if (TREE_TYPE (val) == error_mark_node)
1465 /* Make sure constraint has `=' and does not have `+'. Also, see
1466 if it allows any register. Be liberal on the latter test, since
1467 the worst that happens if we get it wrong is we issue an error
1470 for (j = 0; j < TREE_STRING_LENGTH (TREE_PURPOSE (tail)) - 1; j++)
1471 switch (TREE_STRING_POINTER (TREE_PURPOSE (tail))[j])
1474 /* Make sure we can specify the matching operand. */
1477 error ("output operand constraint %d contains `+'", i);
1481 /* Replace '+' with '='. */
1482 TREE_STRING_POINTER (TREE_PURPOSE (tail))[j] = '=';
1490 case '?': case '!': case '*': case '%': case '&':
1491 case 'V': case 'm': case 'o': case '<': case '>':
1492 case 'E': case 'F': case 'G': case 'H': case 'X':
1493 case 's': case 'i': case 'n':
1494 case 'I': case 'J': case 'K': case 'L': case 'M':
1495 case 'N': case 'O': case 'P': case ',':
1496 #ifdef EXTRA_CONSTRAINT
1497 case 'Q': case 'R': case 'S': case 'T': case 'U':
1501 case '0': case '1': case '2': case '3': case '4':
1502 case '5': case '6': case '7': case '8': case '9':
1503 error ("matching constraint not valid in output operand");
1506 case 'p': case 'g': case 'r':
1512 if (! found_equal && ! found_plus)
1514 error ("output operand constraint lacks `='");
1518 /* If an output operand is not a decl or indirect ref and our constraint
1519 allows a register, make a temporary to act as an intermediate.
1520 Make the asm insn write into that, then our caller will copy it to
1521 the real output operand. Likewise for promoted variables. */
1523 if (TREE_CODE (val) == INDIRECT_REF
1524 || (TREE_CODE_CLASS (TREE_CODE (val)) == 'd'
1525 && ! (GET_CODE (DECL_RTL (val)) == REG
1526 && GET_MODE (DECL_RTL (val)) != TYPE_MODE (type)))
1531 mark_addressable (TREE_VALUE (tail));
1534 = expand_expr (TREE_VALUE (tail), NULL_RTX, VOIDmode,
1535 EXPAND_MEMORY_USE_WO);
1537 if (! allows_reg && GET_CODE (output_rtx[i]) != MEM)
1538 error ("output number %d not directly addressable", i);
1542 output_rtx[i] = assign_temp (type, 0, 0, 0);
1543 TREE_VALUE (tail) = make_tree (type, output_rtx[i]);
1548 inout_mode[ninout] = TYPE_MODE (TREE_TYPE (TREE_VALUE (tail)));
1549 inout_opnum[ninout++] = i;
1554 if (ninputs + noutputs > MAX_RECOG_OPERANDS)
1556 error ("more than %d operands in `asm'", MAX_RECOG_OPERANDS);
1560 /* Make vectors for the expression-rtx and constraint strings. */
1562 argvec = rtvec_alloc (ninputs);
1563 constraints = rtvec_alloc (ninputs);
1565 body = gen_rtx (ASM_OPERANDS, VOIDmode,
1566 TREE_STRING_POINTER (string), "", 0, argvec, constraints,
1568 MEM_VOLATILE_P (body) = vol;
1570 /* Eval the inputs and put them into ARGVEC.
1571 Put their constraints into ASM_INPUTs and store in CONSTRAINTS. */
1574 for (tail = inputs; tail; tail = TREE_CHAIN (tail))
1579 /* If there's an erroneous arg, emit no insn,
1580 because the ASM_INPUT would get VOIDmode
1581 and that could cause a crash in reload. */
1582 if (TREE_TYPE (TREE_VALUE (tail)) == error_mark_node)
1584 if (TREE_PURPOSE (tail) == NULL_TREE)
1586 error ("hard register `%s' listed as input operand to `asm'",
1587 TREE_STRING_POINTER (TREE_VALUE (tail)) );
1591 /* Make sure constraint has neither `=' nor `+'. */
1593 for (j = 0; j < TREE_STRING_LENGTH (TREE_PURPOSE (tail)) - 1; j++)
1594 switch (TREE_STRING_POINTER (TREE_PURPOSE (tail))[j])
1597 error ("input operand constraint contains `%c'",
1598 TREE_STRING_POINTER (TREE_PURPOSE (tail))[j]);
1601 case '?': case '!': case '*': case '%': case '&':
1602 case 'V': case 'm': case 'o': case '<': case '>':
1603 case 'E': case 'F': case 'G': case 'H': case 'X':
1604 case 's': case 'i': case 'n':
1605 case 'I': case 'J': case 'K': case 'L': case 'M':
1606 case 'N': case 'O': case 'P': case ',':
1607 #ifdef EXTRA_CONSTRAINT
1608 case 'Q': case 'R': case 'S': case 'T': case 'U':
1612 /* Whether or not a numeric constraint allows a register is
1613 decided by the matching constraint, and so there is no need
1614 to do anything special with them. We must handle them in
1615 the default case, so that we don't unnecessarily force
1616 operands to memory. */
1617 case '0': case '1': case '2': case '3': case '4':
1618 case '5': case '6': case '7': case '8': case '9':
1619 if (TREE_STRING_POINTER (TREE_PURPOSE (tail))[j]
1623 ("matching constraint references invalid operand number");
1627 /* ... fall through ... */
1629 case 'p': case 'g': case 'r':
1636 mark_addressable (TREE_VALUE (tail));
1638 XVECEXP (body, 3, i) /* argvec */
1639 = expand_expr (TREE_VALUE (tail), NULL_RTX, VOIDmode, 0);
1640 if (CONSTANT_P (XVECEXP (body, 3, i))
1641 && ! general_operand (XVECEXP (body, 3, i),
1642 TYPE_MODE (TREE_TYPE (TREE_VALUE (tail)))))
1645 XVECEXP (body, 3, i)
1646 = force_reg (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail))),
1647 XVECEXP (body, 3, i));
1649 XVECEXP (body, 3, i)
1650 = force_const_mem (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail))),
1651 XVECEXP (body, 3, i));
1655 && (GET_CODE (XVECEXP (body, 3, i)) == REG
1656 || GET_CODE (XVECEXP (body, 3, i)) == SUBREG
1657 || GET_CODE (XVECEXP (body, 3, i)) == CONCAT))
1659 tree type = TREE_TYPE (TREE_VALUE (tail));
1660 rtx memloc = assign_temp (type, 1, 1, 1);
1662 emit_move_insn (memloc, XVECEXP (body, 3, i));
1663 XVECEXP (body, 3, i) = memloc;
1666 XVECEXP (body, 4, i) /* constraints */
1667 = gen_rtx (ASM_INPUT, TYPE_MODE (TREE_TYPE (TREE_VALUE (tail))),
1668 TREE_STRING_POINTER (TREE_PURPOSE (tail)));
1672 /* Protect all the operands from the queue,
1673 now that they have all been evaluated. */
1675 for (i = 0; i < ninputs - ninout; i++)
1676 XVECEXP (body, 3, i) = protect_from_queue (XVECEXP (body, 3, i), 0);
1678 for (i = 0; i < noutputs; i++)
1679 output_rtx[i] = protect_from_queue (output_rtx[i], 1);
1681 /* For in-out operands, copy output rtx to input rtx. */
1682 for (i = 0; i < ninout; i++)
1684 static char match[9+1][2]
1685 = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9"};
1686 int j = inout_opnum[i];
1688 XVECEXP (body, 3, ninputs - ninout + i) /* argvec */
1690 XVECEXP (body, 4, ninputs - ninout + i) /* constraints */
1691 = gen_rtx (ASM_INPUT, inout_mode[j], match[j]);
1694 /* Now, for each output, construct an rtx
1695 (set OUTPUT (asm_operands INSN OUTPUTNUMBER OUTPUTCONSTRAINT
1696 ARGVEC CONSTRAINTS))
1697 If there is more than one, put them inside a PARALLEL. */
1699 if (noutputs == 1 && nclobbers == 0)
1701 XSTR (body, 1) = TREE_STRING_POINTER (TREE_PURPOSE (outputs));
1702 insn = emit_insn (gen_rtx (SET, VOIDmode, output_rtx[0], body));
1704 else if (noutputs == 0 && nclobbers == 0)
1706 /* No output operands: put in a raw ASM_OPERANDS rtx. */
1707 insn = emit_insn (body);
1713 if (num == 0) num = 1;
1714 body = gen_rtx (PARALLEL, VOIDmode, rtvec_alloc (num + nclobbers));
1716 /* For each output operand, store a SET. */
1718 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
1720 XVECEXP (body, 0, i)
1721 = gen_rtx (SET, VOIDmode,
1723 gen_rtx (ASM_OPERANDS, VOIDmode,
1724 TREE_STRING_POINTER (string),
1725 TREE_STRING_POINTER (TREE_PURPOSE (tail)),
1726 i, argvec, constraints,
1728 MEM_VOLATILE_P (SET_SRC (XVECEXP (body, 0, i))) = vol;
1731 /* If there are no outputs (but there are some clobbers)
1732 store the bare ASM_OPERANDS into the PARALLEL. */
1735 XVECEXP (body, 0, i++) = obody;
1737 /* Store (clobber REG) for each clobbered register specified. */
1739 for (tail = clobbers; tail; tail = TREE_CHAIN (tail))
1741 char *regname = TREE_STRING_POINTER (TREE_VALUE (tail));
1742 int j = decode_reg_name (regname);
1746 if (j == -3) /* `cc', which is not a register */
1749 if (j == -4) /* `memory', don't cache memory across asm */
1751 XVECEXP (body, 0, i++)
1752 = gen_rtx (CLOBBER, VOIDmode,
1753 gen_rtx (MEM, BLKmode,
1754 gen_rtx (SCRATCH, VOIDmode, 0)));
1758 /* Ignore unknown register, error already signaled. */
1762 /* Use QImode since that's guaranteed to clobber just one reg. */
1763 XVECEXP (body, 0, i++)
1764 = gen_rtx (CLOBBER, VOIDmode, gen_rtx (REG, QImode, j));
1767 insn = emit_insn (body);
1773 /* Generate RTL to evaluate the expression EXP
1774 and remember it in case this is the VALUE in a ({... VALUE; }) constr. */
1777 expand_expr_stmt (exp)
1780 if (output_bytecode)
1782 int org_stack_depth = stack_depth;
1784 bc_expand_expr (exp);
1786 /* Restore stack depth */
1787 if (stack_depth < org_stack_depth)
1790 bc_emit_instruction (drop);
1792 last_expr_type = TREE_TYPE (exp);
1796 /* If -W, warn about statements with no side effects,
1797 except for an explicit cast to void (e.g. for assert()), and
1798 except inside a ({...}) where they may be useful. */
1799 if (expr_stmts_for_value == 0 && exp != error_mark_node)
1801 if (! TREE_SIDE_EFFECTS (exp) && (extra_warnings || warn_unused)
1802 && !(TREE_CODE (exp) == CONVERT_EXPR
1803 && TREE_TYPE (exp) == void_type_node))
1804 warning_with_file_and_line (emit_filename, emit_lineno,
1805 "statement with no effect");
1806 else if (warn_unused)
1807 warn_if_unused_value (exp);
1810 /* If EXP is of function type and we are expanding statements for
1811 value, convert it to pointer-to-function. */
1812 if (expr_stmts_for_value && TREE_CODE (TREE_TYPE (exp)) == FUNCTION_TYPE)
1813 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1815 last_expr_type = TREE_TYPE (exp);
1816 if (! flag_syntax_only)
1817 last_expr_value = expand_expr (exp,
1818 (expr_stmts_for_value
1819 ? NULL_RTX : const0_rtx),
1822 /* If all we do is reference a volatile value in memory,
1823 copy it to a register to be sure it is actually touched. */
1824 if (last_expr_value != 0 && GET_CODE (last_expr_value) == MEM
1825 && TREE_THIS_VOLATILE (exp))
1827 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode)
1829 else if (TYPE_MODE (TREE_TYPE (exp)) != BLKmode)
1830 copy_to_reg (last_expr_value);
1833 rtx lab = gen_label_rtx ();
1835 /* Compare the value with itself to reference it. */
1836 emit_cmp_insn (last_expr_value, last_expr_value, EQ,
1837 expand_expr (TYPE_SIZE (last_expr_type),
1838 NULL_RTX, VOIDmode, 0),
1840 TYPE_ALIGN (last_expr_type) / BITS_PER_UNIT);
1841 emit_jump_insn ((*bcc_gen_fctn[(int) EQ]) (lab));
1846 /* If this expression is part of a ({...}) and is in memory, we may have
1847 to preserve temporaries. */
1848 preserve_temp_slots (last_expr_value);
1850 /* Free any temporaries used to evaluate this expression. Any temporary
1851 used as a result of this expression will already have been preserved
1858 /* Warn if EXP contains any computations whose results are not used.
1859 Return 1 if a warning is printed; 0 otherwise. */
1862 warn_if_unused_value (exp)
1865 if (TREE_USED (exp))
1868 switch (TREE_CODE (exp))
1870 case PREINCREMENT_EXPR:
1871 case POSTINCREMENT_EXPR:
1872 case PREDECREMENT_EXPR:
1873 case POSTDECREMENT_EXPR:
1878 case METHOD_CALL_EXPR:
1880 case TRY_CATCH_EXPR:
1881 case WITH_CLEANUP_EXPR:
1883 /* We don't warn about COND_EXPR because it may be a useful
1884 construct if either arm contains a side effect. */
1889 /* For a binding, warn if no side effect within it. */
1890 return warn_if_unused_value (TREE_OPERAND (exp, 1));
1893 return warn_if_unused_value (TREE_OPERAND (exp, 1));
1895 case TRUTH_ORIF_EXPR:
1896 case TRUTH_ANDIF_EXPR:
1897 /* In && or ||, warn if 2nd operand has no side effect. */
1898 return warn_if_unused_value (TREE_OPERAND (exp, 1));
1901 if (TREE_NO_UNUSED_WARNING (exp))
1903 if (warn_if_unused_value (TREE_OPERAND (exp, 0)))
1905 /* Let people do `(foo (), 0)' without a warning. */
1906 if (TREE_CONSTANT (TREE_OPERAND (exp, 1)))
1908 return warn_if_unused_value (TREE_OPERAND (exp, 1));
1912 case NON_LVALUE_EXPR:
1913 /* Don't warn about values cast to void. */
1914 if (TREE_TYPE (exp) == void_type_node)
1916 /* Don't warn about conversions not explicit in the user's program. */
1917 if (TREE_NO_UNUSED_WARNING (exp))
1919 /* Assignment to a cast usually results in a cast of a modify.
1920 Don't complain about that. There can be an arbitrary number of
1921 casts before the modify, so we must loop until we find the first
1922 non-cast expression and then test to see if that is a modify. */
1924 tree tem = TREE_OPERAND (exp, 0);
1926 while (TREE_CODE (tem) == CONVERT_EXPR || TREE_CODE (tem) == NOP_EXPR)
1927 tem = TREE_OPERAND (tem, 0);
1929 if (TREE_CODE (tem) == MODIFY_EXPR || TREE_CODE (tem) == INIT_EXPR
1930 || TREE_CODE (tem) == CALL_EXPR)
1936 /* Don't warn about automatic dereferencing of references, since
1937 the user cannot control it. */
1938 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == REFERENCE_TYPE)
1939 return warn_if_unused_value (TREE_OPERAND (exp, 0));
1940 /* ... fall through ... */
1943 /* Referencing a volatile value is a side effect, so don't warn. */
1944 if ((TREE_CODE_CLASS (TREE_CODE (exp)) == 'd'
1945 || TREE_CODE_CLASS (TREE_CODE (exp)) == 'r')
1946 && TREE_THIS_VOLATILE (exp))
1949 warning_with_file_and_line (emit_filename, emit_lineno,
1950 "value computed is not used");
1955 /* Clear out the memory of the last expression evaluated. */
1963 /* Begin a statement which will return a value.
1964 Return the RTL_EXPR for this statement expr.
1965 The caller must save that value and pass it to expand_end_stmt_expr. */
1968 expand_start_stmt_expr ()
1973 /* When generating bytecode just note down the stack depth */
1974 if (output_bytecode)
1975 return (build_int_2 (stack_depth, 0));
1977 /* Make the RTL_EXPR node temporary, not momentary,
1978 so that rtl_expr_chain doesn't become garbage. */
1979 momentary = suspend_momentary ();
1980 t = make_node (RTL_EXPR);
1981 resume_momentary (momentary);
1982 do_pending_stack_adjust ();
1983 start_sequence_for_rtl_expr (t);
1985 expr_stmts_for_value++;
1989 /* Restore the previous state at the end of a statement that returns a value.
1990 Returns a tree node representing the statement's value and the
1991 insns to compute the value.
1993 The nodes of that expression have been freed by now, so we cannot use them.
1994 But we don't want to do that anyway; the expression has already been
1995 evaluated and now we just want to use the value. So generate a RTL_EXPR
1996 with the proper type and RTL value.
1998 If the last substatement was not an expression,
1999 return something with type `void'. */
2002 expand_end_stmt_expr (t)
2005 if (output_bytecode)
2011 /* At this point, all expressions have been evaluated in order.
2012 However, all expression values have been popped when evaluated,
2013 which means we have to recover the last expression value. This is
2014 the last value removed by means of a `drop' instruction. Instead
2015 of adding code to inhibit dropping the last expression value, it
2016 is here recovered by undoing the `drop'. Since `drop' is
2017 equivalent to `adjustackSI [1]', it can be undone with `adjstackSI
2020 bc_adjust_stack (-1);
2022 if (!last_expr_type)
2023 last_expr_type = void_type_node;
2025 t = make_node (RTL_EXPR);
2026 TREE_TYPE (t) = last_expr_type;
2027 RTL_EXPR_RTL (t) = NULL;
2028 RTL_EXPR_SEQUENCE (t) = NULL;
2030 /* Don't consider deleting this expr or containing exprs at tree level. */
2031 TREE_THIS_VOLATILE (t) = 1;
2039 if (last_expr_type == 0)
2041 last_expr_type = void_type_node;
2042 last_expr_value = const0_rtx;
2044 else if (last_expr_value == 0)
2045 /* There are some cases where this can happen, such as when the
2046 statement is void type. */
2047 last_expr_value = const0_rtx;
2048 else if (GET_CODE (last_expr_value) != REG && ! CONSTANT_P (last_expr_value))
2049 /* Remove any possible QUEUED. */
2050 last_expr_value = protect_from_queue (last_expr_value, 0);
2054 TREE_TYPE (t) = last_expr_type;
2055 RTL_EXPR_RTL (t) = last_expr_value;
2056 RTL_EXPR_SEQUENCE (t) = get_insns ();
2058 rtl_expr_chain = tree_cons (NULL_TREE, t, rtl_expr_chain);
2062 /* Don't consider deleting this expr or containing exprs at tree level. */
2063 TREE_SIDE_EFFECTS (t) = 1;
2064 /* Propagate volatility of the actual RTL expr. */
2065 TREE_THIS_VOLATILE (t) = volatile_refs_p (last_expr_value);
2068 expr_stmts_for_value--;
2073 /* Generate RTL for the start of an if-then. COND is the expression
2074 whose truth should be tested.
2076 If EXITFLAG is nonzero, this conditional is visible to
2077 `exit_something'. */
2080 expand_start_cond (cond, exitflag)
2084 struct nesting *thiscond = ALLOC_NESTING ();
2086 /* Make an entry on cond_stack for the cond we are entering. */
2088 thiscond->next = cond_stack;
2089 thiscond->all = nesting_stack;
2090 thiscond->depth = ++nesting_depth;
2091 thiscond->data.cond.next_label = gen_label_rtx ();
2092 /* Before we encounter an `else', we don't need a separate exit label
2093 unless there are supposed to be exit statements
2094 to exit this conditional. */
2095 thiscond->exit_label = exitflag ? gen_label_rtx () : 0;
2096 thiscond->data.cond.endif_label = thiscond->exit_label;
2097 cond_stack = thiscond;
2098 nesting_stack = thiscond;
2100 if (output_bytecode)
2101 bc_expand_start_cond (cond, exitflag);
2103 do_jump (cond, thiscond->data.cond.next_label, NULL_RTX);
2106 /* Generate RTL between then-clause and the elseif-clause
2107 of an if-then-elseif-.... */
2110 expand_start_elseif (cond)
2113 if (cond_stack->data.cond.endif_label == 0)
2114 cond_stack->data.cond.endif_label = gen_label_rtx ();
2115 emit_jump (cond_stack->data.cond.endif_label);
2116 emit_label (cond_stack->data.cond.next_label);
2117 cond_stack->data.cond.next_label = gen_label_rtx ();
2118 do_jump (cond, cond_stack->data.cond.next_label, NULL_RTX);
2121 /* Generate RTL between the then-clause and the else-clause
2122 of an if-then-else. */
2125 expand_start_else ()
2127 if (cond_stack->data.cond.endif_label == 0)
2128 cond_stack->data.cond.endif_label = gen_label_rtx ();
2130 if (output_bytecode)
2132 bc_expand_start_else ();
2136 emit_jump (cond_stack->data.cond.endif_label);
2137 emit_label (cond_stack->data.cond.next_label);
2138 cond_stack->data.cond.next_label = 0; /* No more _else or _elseif calls. */
2141 /* After calling expand_start_else, turn this "else" into an "else if"
2142 by providing another condition. */
2145 expand_elseif (cond)
2148 cond_stack->data.cond.next_label = gen_label_rtx ();
2149 do_jump (cond, cond_stack->data.cond.next_label, NULL_RTX);
2152 /* Generate RTL for the end of an if-then.
2153 Pop the record for it off of cond_stack. */
2158 struct nesting *thiscond = cond_stack;
2160 if (output_bytecode)
2161 bc_expand_end_cond ();
2164 do_pending_stack_adjust ();
2165 if (thiscond->data.cond.next_label)
2166 emit_label (thiscond->data.cond.next_label);
2167 if (thiscond->data.cond.endif_label)
2168 emit_label (thiscond->data.cond.endif_label);
2171 POPSTACK (cond_stack);
2176 /* Generate code for the start of an if-then. COND is the expression
2177 whose truth is to be tested; if EXITFLAG is nonzero this conditional
2178 is to be visible to exit_something. It is assumed that the caller
2179 has pushed the previous context on the cond stack. */
2182 bc_expand_start_cond (cond, exitflag)
2186 struct nesting *thiscond = cond_stack;
2188 thiscond->data.case_stmt.nominal_type = cond;
2190 thiscond->exit_label = gen_label_rtx ();
2191 bc_expand_expr (cond);
2192 bc_emit_bytecode (xjumpifnot);
2193 bc_emit_bytecode_labelref (BYTECODE_BC_LABEL (thiscond->exit_label));
2195 #ifdef DEBUG_PRINT_CODE
2196 fputc ('\n', stderr);
2200 /* Generate the label for the end of an if with
2204 bc_expand_end_cond ()
2206 struct nesting *thiscond = cond_stack;
2208 bc_emit_bytecode_labeldef (BYTECODE_BC_LABEL (thiscond->exit_label));
2211 /* Generate code for the start of the else- clause of
2215 bc_expand_start_else ()
2217 struct nesting *thiscond = cond_stack;
2219 thiscond->data.cond.endif_label = thiscond->exit_label;
2220 thiscond->exit_label = gen_label_rtx ();
2221 bc_emit_bytecode (jump);
2222 bc_emit_bytecode_labelref (BYTECODE_BC_LABEL (thiscond->exit_label));
2224 #ifdef DEBUG_PRINT_CODE
2225 fputc ('\n', stderr);
2228 bc_emit_bytecode_labeldef (BYTECODE_BC_LABEL (thiscond->data.cond.endif_label));
2231 /* Generate RTL for the start of a loop. EXIT_FLAG is nonzero if this
2232 loop should be exited by `exit_something'. This is a loop for which
2233 `expand_continue' will jump to the top of the loop.
2235 Make an entry on loop_stack to record the labels associated with
2239 expand_start_loop (exit_flag)
2242 register struct nesting *thisloop = ALLOC_NESTING ();
2244 /* Make an entry on loop_stack for the loop we are entering. */
2246 thisloop->next = loop_stack;
2247 thisloop->all = nesting_stack;
2248 thisloop->depth = ++nesting_depth;
2249 thisloop->data.loop.start_label = gen_label_rtx ();
2250 thisloop->data.loop.end_label = gen_label_rtx ();
2251 thisloop->data.loop.alt_end_label = 0;
2252 thisloop->data.loop.continue_label = thisloop->data.loop.start_label;
2253 thisloop->exit_label = exit_flag ? thisloop->data.loop.end_label : 0;
2254 loop_stack = thisloop;
2255 nesting_stack = thisloop;
2257 if (output_bytecode)
2259 bc_emit_bytecode_labeldef (BYTECODE_BC_LABEL (thisloop->data.loop.start_label));
2263 do_pending_stack_adjust ();
2265 emit_note (NULL_PTR, NOTE_INSN_LOOP_BEG);
2266 emit_label (thisloop->data.loop.start_label);
2271 /* Like expand_start_loop but for a loop where the continuation point
2272 (for expand_continue_loop) will be specified explicitly. */
2275 expand_start_loop_continue_elsewhere (exit_flag)
2278 struct nesting *thisloop = expand_start_loop (exit_flag);
2279 loop_stack->data.loop.continue_label = gen_label_rtx ();
2283 /* Specify the continuation point for a loop started with
2284 expand_start_loop_continue_elsewhere.
2285 Use this at the point in the code to which a continue statement
2289 expand_loop_continue_here ()
2291 if (output_bytecode)
2293 bc_emit_bytecode_labeldef (BYTECODE_BC_LABEL (loop_stack->data.loop.continue_label));
2296 do_pending_stack_adjust ();
2297 emit_note (NULL_PTR, NOTE_INSN_LOOP_CONT);
2298 emit_label (loop_stack->data.loop.continue_label);
2304 bc_expand_end_loop ()
2306 struct nesting *thisloop = loop_stack;
2308 bc_emit_bytecode (jump);
2309 bc_emit_bytecode_labelref (BYTECODE_BC_LABEL (thisloop->data.loop.start_label));
2311 #ifdef DEBUG_PRINT_CODE
2312 fputc ('\n', stderr);
2315 bc_emit_bytecode_labeldef (BYTECODE_BC_LABEL (thisloop->exit_label));
2316 POPSTACK (loop_stack);
2321 /* Finish a loop. Generate a jump back to the top and the loop-exit label.
2322 Pop the block off of loop_stack. */
2328 register rtx start_label;
2329 rtx last_test_insn = 0;
2332 if (output_bytecode)
2334 bc_expand_end_loop ();
2338 insn = get_last_insn ();
2339 start_label = loop_stack->data.loop.start_label;
2341 /* Mark the continue-point at the top of the loop if none elsewhere. */
2342 if (start_label == loop_stack->data.loop.continue_label)
2343 emit_note_before (NOTE_INSN_LOOP_CONT, start_label);
2345 do_pending_stack_adjust ();
2347 /* If optimizing, perhaps reorder the loop. If the loop
2348 starts with a conditional exit, roll that to the end
2349 where it will optimize together with the jump back.
2351 We look for the last conditional branch to the exit that we encounter
2352 before hitting 30 insns or a CALL_INSN. If we see an unconditional
2353 branch to the exit first, use it.
2355 We must also stop at NOTE_INSN_BLOCK_BEG and NOTE_INSN_BLOCK_END notes
2356 because moving them is not valid. */
2360 ! (GET_CODE (insn) == JUMP_INSN
2361 && GET_CODE (PATTERN (insn)) == SET
2362 && SET_DEST (PATTERN (insn)) == pc_rtx
2363 && GET_CODE (SET_SRC (PATTERN (insn))) == IF_THEN_ELSE))
2365 /* Scan insns from the top of the loop looking for a qualified
2366 conditional exit. */
2367 for (insn = NEXT_INSN (loop_stack->data.loop.start_label); insn;
2368 insn = NEXT_INSN (insn))
2370 if (GET_CODE (insn) == CALL_INSN || GET_CODE (insn) == CODE_LABEL)
2373 if (GET_CODE (insn) == NOTE
2374 && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG
2375 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END))
2378 if (GET_CODE (insn) == JUMP_INSN || GET_CODE (insn) == INSN)
2381 if (last_test_insn && num_insns > 30)
2384 if (GET_CODE (insn) == JUMP_INSN && GET_CODE (PATTERN (insn)) == SET
2385 && SET_DEST (PATTERN (insn)) == pc_rtx
2386 && GET_CODE (SET_SRC (PATTERN (insn))) == IF_THEN_ELSE
2387 && ((GET_CODE (XEXP (SET_SRC (PATTERN (insn)), 1)) == LABEL_REF
2388 && ((XEXP (XEXP (SET_SRC (PATTERN (insn)), 1), 0)
2389 == loop_stack->data.loop.end_label)
2390 || (XEXP (XEXP (SET_SRC (PATTERN (insn)), 1), 0)
2391 == loop_stack->data.loop.alt_end_label)))
2392 || (GET_CODE (XEXP (SET_SRC (PATTERN (insn)), 2)) == LABEL_REF
2393 && ((XEXP (XEXP (SET_SRC (PATTERN (insn)), 2), 0)
2394 == loop_stack->data.loop.end_label)
2395 || (XEXP (XEXP (SET_SRC (PATTERN (insn)), 2), 0)
2396 == loop_stack->data.loop.alt_end_label)))))
2397 last_test_insn = insn;
2399 if (last_test_insn == 0 && GET_CODE (insn) == JUMP_INSN
2400 && GET_CODE (PATTERN (insn)) == SET
2401 && SET_DEST (PATTERN (insn)) == pc_rtx
2402 && GET_CODE (SET_SRC (PATTERN (insn))) == LABEL_REF
2403 && ((XEXP (SET_SRC (PATTERN (insn)), 0)
2404 == loop_stack->data.loop.end_label)
2405 || (XEXP (SET_SRC (PATTERN (insn)), 0)
2406 == loop_stack->data.loop.alt_end_label)))
2407 /* Include BARRIER. */
2408 last_test_insn = NEXT_INSN (insn);
2411 if (last_test_insn != 0 && last_test_insn != get_last_insn ())
2413 /* We found one. Move everything from there up
2414 to the end of the loop, and add a jump into the loop
2415 to jump to there. */
2416 register rtx newstart_label = gen_label_rtx ();
2417 register rtx start_move = start_label;
2419 /* If the start label is preceded by a NOTE_INSN_LOOP_CONT note,
2420 then we want to move this note also. */
2421 if (GET_CODE (PREV_INSN (start_move)) == NOTE
2422 && (NOTE_LINE_NUMBER (PREV_INSN (start_move))
2423 == NOTE_INSN_LOOP_CONT))
2424 start_move = PREV_INSN (start_move);
2426 emit_label_after (newstart_label, PREV_INSN (start_move));
2427 reorder_insns (start_move, last_test_insn, get_last_insn ());
2428 emit_jump_insn_after (gen_jump (start_label),
2429 PREV_INSN (newstart_label));
2430 emit_barrier_after (PREV_INSN (newstart_label));
2431 start_label = newstart_label;
2435 emit_jump (start_label);
2436 emit_note (NULL_PTR, NOTE_INSN_LOOP_END);
2437 emit_label (loop_stack->data.loop.end_label);
2439 POPSTACK (loop_stack);
2444 /* Generate a jump to the current loop's continue-point.
2445 This is usually the top of the loop, but may be specified
2446 explicitly elsewhere. If not currently inside a loop,
2447 return 0 and do nothing; caller will print an error message. */
2450 expand_continue_loop (whichloop)
2451 struct nesting *whichloop;
2455 whichloop = loop_stack;
2458 expand_goto_internal (NULL_TREE, whichloop->data.loop.continue_label,
2463 /* Generate a jump to exit the current loop. If not currently inside a loop,
2464 return 0 and do nothing; caller will print an error message. */
2467 expand_exit_loop (whichloop)
2468 struct nesting *whichloop;
2472 whichloop = loop_stack;
2475 expand_goto_internal (NULL_TREE, whichloop->data.loop.end_label, NULL_RTX);
2479 /* Generate a conditional jump to exit the current loop if COND
2480 evaluates to zero. If not currently inside a loop,
2481 return 0 and do nothing; caller will print an error message. */
2484 expand_exit_loop_if_false (whichloop, cond)
2485 struct nesting *whichloop;
2490 whichloop = loop_stack;
2493 if (output_bytecode)
2495 bc_expand_expr (cond);
2496 bc_expand_goto_internal (xjumpifnot,
2497 BYTECODE_BC_LABEL (whichloop->exit_label),
2502 /* In order to handle fixups, we actually create a conditional jump
2503 around a unconditional branch to exit the loop. If fixups are
2504 necessary, they go before the unconditional branch. */
2506 rtx label = gen_label_rtx ();
2509 do_jump (cond, NULL_RTX, label);
2510 last_insn = get_last_insn ();
2511 if (GET_CODE (last_insn) == CODE_LABEL)
2512 whichloop->data.loop.alt_end_label = last_insn;
2513 expand_goto_internal (NULL_TREE, whichloop->data.loop.end_label,
2521 /* Return non-zero if we should preserve sub-expressions as separate
2522 pseudos. We never do so if we aren't optimizing. We always do so
2523 if -fexpensive-optimizations.
2525 Otherwise, we only do so if we are in the "early" part of a loop. I.e.,
2526 the loop may still be a small one. */
2529 preserve_subexpressions_p ()
2533 if (flag_expensive_optimizations)
2536 if (optimize == 0 || loop_stack == 0)
2539 insn = get_last_insn_anywhere ();
2542 && (INSN_UID (insn) - INSN_UID (loop_stack->data.loop.start_label)
2543 < n_non_fixed_regs * 3));
2547 /* Generate a jump to exit the current loop, conditional, binding contour
2548 or case statement. Not all such constructs are visible to this function,
2549 only those started with EXIT_FLAG nonzero. Individual languages use
2550 the EXIT_FLAG parameter to control which kinds of constructs you can
2553 If not currently inside anything that can be exited,
2554 return 0 and do nothing; caller will print an error message. */
2557 expand_exit_something ()
2561 for (n = nesting_stack; n; n = n->all)
2562 if (n->exit_label != 0)
2564 expand_goto_internal (NULL_TREE, n->exit_label, NULL_RTX);
2571 /* Generate RTL to return from the current function, with no value.
2572 (That is, we do not do anything about returning any value.) */
2575 expand_null_return ()
2577 struct nesting *block = block_stack;
2580 if (output_bytecode)
2582 bc_emit_instruction (ret);
2586 /* Does any pending block have cleanups? */
2588 while (block && block->data.block.cleanups == 0)
2589 block = block->next;
2591 /* If yes, use a goto to return, since that runs cleanups. */
2593 expand_null_return_1 (last_insn, block != 0);
2596 /* Generate RTL to return from the current function, with value VAL. */
2599 expand_value_return (val)
2602 struct nesting *block = block_stack;
2603 rtx last_insn = get_last_insn ();
2604 rtx return_reg = DECL_RTL (DECL_RESULT (current_function_decl));
2606 /* Copy the value to the return location
2607 unless it's already there. */
2609 if (return_reg != val)
2611 #ifdef PROMOTE_FUNCTION_RETURN
2612 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
2613 int unsignedp = TREE_UNSIGNED (type);
2614 enum machine_mode mode
2615 = promote_mode (type, DECL_MODE (DECL_RESULT (current_function_decl)),
2618 if (GET_MODE (val) != VOIDmode && GET_MODE (val) != mode)
2619 convert_move (return_reg, val, unsignedp);
2622 emit_move_insn (return_reg, val);
2624 if (GET_CODE (return_reg) == REG
2625 && REGNO (return_reg) < FIRST_PSEUDO_REGISTER)
2626 emit_insn (gen_rtx (USE, VOIDmode, return_reg));
2627 /* Handle calls that return values in multiple non-contiguous locations.
2628 The Irix 6 ABI has examples of this. */
2629 else if (GET_CODE (return_reg) == PARALLEL)
2633 for (i = 0; i < XVECLEN (return_reg, 0); i++)
2635 rtx x = XEXP (XVECEXP (return_reg, 0, i), 0);
2637 if (GET_CODE (x) == REG
2638 && REGNO (x) < FIRST_PSEUDO_REGISTER)
2639 emit_insn (gen_rtx (USE, VOIDmode, x));
2643 /* Does any pending block have cleanups? */
2645 while (block && block->data.block.cleanups == 0)
2646 block = block->next;
2648 /* If yes, use a goto to return, since that runs cleanups.
2649 Use LAST_INSN to put cleanups *before* the move insn emitted above. */
2651 expand_null_return_1 (last_insn, block != 0);
2654 /* Output a return with no value. If LAST_INSN is nonzero,
2655 pretend that the return takes place after LAST_INSN.
2656 If USE_GOTO is nonzero then don't use a return instruction;
2657 go to the return label instead. This causes any cleanups
2658 of pending blocks to be executed normally. */
2661 expand_null_return_1 (last_insn, use_goto)
2665 rtx end_label = cleanup_label ? cleanup_label : return_label;
2667 clear_pending_stack_adjust ();
2668 do_pending_stack_adjust ();
2671 /* PCC-struct return always uses an epilogue. */
2672 if (current_function_returns_pcc_struct || use_goto)
2675 end_label = return_label = gen_label_rtx ();
2676 expand_goto_internal (NULL_TREE, end_label, last_insn);
2680 /* Otherwise output a simple return-insn if one is available,
2681 unless it won't do the job. */
2683 if (HAVE_return && use_goto == 0 && cleanup_label == 0)
2685 emit_jump_insn (gen_return ());
2691 /* Otherwise jump to the epilogue. */
2692 expand_goto_internal (NULL_TREE, end_label, last_insn);
2695 /* Generate RTL to evaluate the expression RETVAL and return it
2696 from the current function. */
2699 expand_return (retval)
2702 /* If there are any cleanups to be performed, then they will
2703 be inserted following LAST_INSN. It is desirable
2704 that the last_insn, for such purposes, should be the
2705 last insn before computing the return value. Otherwise, cleanups
2706 which call functions can clobber the return value. */
2707 /* ??? rms: I think that is erroneous, because in C++ it would
2708 run destructors on variables that might be used in the subsequent
2709 computation of the return value. */
2711 register rtx val = 0;
2715 struct nesting *block;
2717 /* Bytecode returns are quite simple, just leave the result on the
2718 arithmetic stack. */
2719 if (output_bytecode)
2721 bc_expand_expr (retval);
2722 bc_emit_instruction (ret);
2726 /* If function wants no value, give it none. */
2727 if (TREE_CODE (TREE_TYPE (TREE_TYPE (current_function_decl))) == VOID_TYPE)
2729 expand_expr (retval, NULL_RTX, VOIDmode, 0);
2731 expand_null_return ();
2735 /* Are any cleanups needed? E.g. C++ destructors to be run? */
2736 /* This is not sufficient. We also need to watch for cleanups of the
2737 expression we are about to expand. Unfortunately, we cannot know
2738 if it has cleanups until we expand it, and we want to change how we
2739 expand it depending upon if we need cleanups. We can't win. */
2741 cleanups = any_pending_cleanups (1);
2746 if (TREE_CODE (retval) == RESULT_DECL)
2747 retval_rhs = retval;
2748 else if ((TREE_CODE (retval) == MODIFY_EXPR || TREE_CODE (retval) == INIT_EXPR)
2749 && TREE_CODE (TREE_OPERAND (retval, 0)) == RESULT_DECL)
2750 retval_rhs = TREE_OPERAND (retval, 1);
2751 else if (TREE_TYPE (retval) == void_type_node)
2752 /* Recognize tail-recursive call to void function. */
2753 retval_rhs = retval;
2755 retval_rhs = NULL_TREE;
2757 /* Only use `last_insn' if there are cleanups which must be run. */
2758 if (cleanups || cleanup_label != 0)
2759 last_insn = get_last_insn ();
2761 /* Distribute return down conditional expr if either of the sides
2762 may involve tail recursion (see test below). This enhances the number
2763 of tail recursions we see. Don't do this always since it can produce
2764 sub-optimal code in some cases and we distribute assignments into
2765 conditional expressions when it would help. */
2767 if (optimize && retval_rhs != 0
2768 && frame_offset == 0
2769 && TREE_CODE (retval_rhs) == COND_EXPR
2770 && (TREE_CODE (TREE_OPERAND (retval_rhs, 1)) == CALL_EXPR
2771 || TREE_CODE (TREE_OPERAND (retval_rhs, 2)) == CALL_EXPR))
2773 rtx label = gen_label_rtx ();
2776 do_jump (TREE_OPERAND (retval_rhs, 0), label, NULL_RTX);
2777 expr = build (MODIFY_EXPR, TREE_TYPE (TREE_TYPE (current_function_decl)),
2778 DECL_RESULT (current_function_decl),
2779 TREE_OPERAND (retval_rhs, 1));
2780 TREE_SIDE_EFFECTS (expr) = 1;
2781 expand_return (expr);
2784 expr = build (MODIFY_EXPR, TREE_TYPE (TREE_TYPE (current_function_decl)),
2785 DECL_RESULT (current_function_decl),
2786 TREE_OPERAND (retval_rhs, 2));
2787 TREE_SIDE_EFFECTS (expr) = 1;
2788 expand_return (expr);
2792 /* For tail-recursive call to current function,
2793 just jump back to the beginning.
2794 It's unsafe if any auto variable in this function
2795 has its address taken; for simplicity,
2796 require stack frame to be empty. */
2797 if (optimize && retval_rhs != 0
2798 && frame_offset == 0
2799 && TREE_CODE (retval_rhs) == CALL_EXPR
2800 && TREE_CODE (TREE_OPERAND (retval_rhs, 0)) == ADDR_EXPR
2801 && TREE_OPERAND (TREE_OPERAND (retval_rhs, 0), 0) == current_function_decl
2802 /* Finish checking validity, and if valid emit code
2803 to set the argument variables for the new call. */
2804 && tail_recursion_args (TREE_OPERAND (retval_rhs, 1),
2805 DECL_ARGUMENTS (current_function_decl)))
2807 if (tail_recursion_label == 0)
2809 tail_recursion_label = gen_label_rtx ();
2810 emit_label_after (tail_recursion_label,
2811 tail_recursion_reentry);
2814 expand_goto_internal (NULL_TREE, tail_recursion_label, last_insn);
2819 /* This optimization is safe if there are local cleanups
2820 because expand_null_return takes care of them.
2821 ??? I think it should also be safe when there is a cleanup label,
2822 because expand_null_return takes care of them, too.
2823 Any reason why not? */
2824 if (HAVE_return && cleanup_label == 0
2825 && ! current_function_returns_pcc_struct
2826 && BRANCH_COST <= 1)
2828 /* If this is return x == y; then generate
2829 if (x == y) return 1; else return 0;
2830 if we can do it with explicit return insns and branches are cheap,
2831 but not if we have the corresponding scc insn. */
2834 switch (TREE_CODE (retval_rhs))
2860 case TRUTH_ANDIF_EXPR:
2861 case TRUTH_ORIF_EXPR:
2862 case TRUTH_AND_EXPR:
2864 case TRUTH_NOT_EXPR:
2865 case TRUTH_XOR_EXPR:
2868 op0 = gen_label_rtx ();
2869 jumpifnot (retval_rhs, op0);
2870 expand_value_return (const1_rtx);
2872 expand_value_return (const0_rtx);
2881 #endif /* HAVE_return */
2883 /* If the result is an aggregate that is being returned in one (or more)
2884 registers, load the registers here. The compiler currently can't handle
2885 copying a BLKmode value into registers. We could put this code in a
2886 more general area (for use by everyone instead of just function
2887 call/return), but until this feature is generally usable it is kept here
2888 (and in expand_call). The value must go into a pseudo in case there
2889 are cleanups that will clobber the real return register. */
2892 && TYPE_MODE (TREE_TYPE (retval_rhs)) == BLKmode
2893 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG)
2895 int i, bitpos, xbitpos;
2896 int big_endian_correction = 0;
2897 int bytes = int_size_in_bytes (TREE_TYPE (retval_rhs));
2898 int n_regs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
2899 int bitsize = MIN (TYPE_ALIGN (TREE_TYPE (retval_rhs)),BITS_PER_WORD);
2900 rtx *result_pseudos = (rtx *) alloca (sizeof (rtx) * n_regs);
2901 rtx result_reg, src, dst;
2902 rtx result_val = expand_expr (retval_rhs, NULL_RTX, VOIDmode, 0);
2903 enum machine_mode tmpmode, result_reg_mode;
2905 /* Structures whose size is not a multiple of a word are aligned
2906 to the least significant byte (to the right). On a BYTES_BIG_ENDIAN
2907 machine, this means we must skip the empty high order bytes when
2908 calculating the bit offset. */
2909 if (BYTES_BIG_ENDIAN && bytes % UNITS_PER_WORD)
2910 big_endian_correction = (BITS_PER_WORD - ((bytes % UNITS_PER_WORD)
2913 /* Copy the structure BITSIZE bits at a time. */
2914 for (bitpos = 0, xbitpos = big_endian_correction;
2915 bitpos < bytes * BITS_PER_UNIT;
2916 bitpos += bitsize, xbitpos += bitsize)
2918 /* We need a new destination pseudo each time xbitpos is
2919 on a word boundary and when xbitpos == big_endian_correction
2920 (the first time through). */
2921 if (xbitpos % BITS_PER_WORD == 0
2922 || xbitpos == big_endian_correction)
2924 /* Generate an appropriate register. */
2925 dst = gen_reg_rtx (word_mode);
2926 result_pseudos[xbitpos / BITS_PER_WORD] = dst;
2928 /* Clobber the destination before we move anything into it. */
2929 emit_insn (gen_rtx (CLOBBER, VOIDmode, dst));
2932 /* We need a new source operand each time bitpos is on a word
2934 if (bitpos % BITS_PER_WORD == 0)
2935 src = operand_subword_force (result_val,
2936 bitpos / BITS_PER_WORD,
2939 /* Use bitpos for the source extraction (left justified) and
2940 xbitpos for the destination store (right justified). */
2941 store_bit_field (dst, bitsize, xbitpos % BITS_PER_WORD, word_mode,
2942 extract_bit_field (src, bitsize,
2943 bitpos % BITS_PER_WORD, 1,
2944 NULL_RTX, word_mode,
2946 bitsize / BITS_PER_UNIT,
2948 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
2951 /* Find the smallest integer mode large enough to hold the
2952 entire structure and use that mode instead of BLKmode
2953 on the USE insn for the return register. */
2954 bytes = int_size_in_bytes (TREE_TYPE (retval_rhs));
2955 for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
2956 tmpmode != MAX_MACHINE_MODE;
2957 tmpmode = GET_MODE_WIDER_MODE (tmpmode))
2959 /* Have we found a large enough mode? */
2960 if (GET_MODE_SIZE (tmpmode) >= bytes)
2964 /* No suitable mode found. */
2965 if (tmpmode == MAX_MACHINE_MODE)
2968 PUT_MODE (DECL_RTL (DECL_RESULT (current_function_decl)), tmpmode);
2970 if (GET_MODE_SIZE (tmpmode) < GET_MODE_SIZE (word_mode))
2971 result_reg_mode = word_mode;
2973 result_reg_mode = tmpmode;
2974 result_reg = gen_reg_rtx (result_reg_mode);
2977 for (i = 0; i < n_regs; i++)
2978 emit_move_insn (operand_subword (result_reg, i, 0, result_reg_mode),
2981 if (tmpmode != result_reg_mode)
2982 result_reg = gen_lowpart (tmpmode, result_reg);
2984 expand_value_return (result_reg);
2988 && TREE_TYPE (retval_rhs) != void_type_node
2989 && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG)
2991 /* Calculate the return value into a pseudo reg. */
2992 val = gen_reg_rtx (DECL_MODE (DECL_RESULT (current_function_decl)));
2993 val = expand_expr (retval_rhs, val, GET_MODE (val), 0);
2994 val = force_not_mem (val);
2996 /* Return the calculated value, doing cleanups first. */
2997 expand_value_return (val);
3001 /* No cleanups or no hard reg used;
3002 calculate value into hard return reg. */
3003 expand_expr (retval, const0_rtx, VOIDmode, 0);
3005 expand_value_return (DECL_RTL (DECL_RESULT (current_function_decl)));
3009 /* Return 1 if the end of the generated RTX is not a barrier.
3010 This means code already compiled can drop through. */
3013 drop_through_at_end_p ()
3015 rtx insn = get_last_insn ();
3016 while (insn && GET_CODE (insn) == NOTE)
3017 insn = PREV_INSN (insn);
3018 return insn && GET_CODE (insn) != BARRIER;
3021 /* Emit code to alter this function's formal parms for a tail-recursive call.
3022 ACTUALS is a list of actual parameter expressions (chain of TREE_LISTs).
3023 FORMALS is the chain of decls of formals.
3024 Return 1 if this can be done;
3025 otherwise return 0 and do not emit any code. */
3028 tail_recursion_args (actuals, formals)
3029 tree actuals, formals;
3031 register tree a = actuals, f = formals;
3033 register rtx *argvec;
3035 /* Check that number and types of actuals are compatible
3036 with the formals. This is not always true in valid C code.
3037 Also check that no formal needs to be addressable
3038 and that all formals are scalars. */
3040 /* Also count the args. */
3042 for (a = actuals, f = formals, i = 0; a && f; a = TREE_CHAIN (a), f = TREE_CHAIN (f), i++)
3044 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_VALUE (a)))
3045 != TYPE_MAIN_VARIANT (TREE_TYPE (f)))
3047 if (GET_CODE (DECL_RTL (f)) != REG || DECL_MODE (f) == BLKmode)
3050 if (a != 0 || f != 0)
3053 /* Compute all the actuals. */
3055 argvec = (rtx *) alloca (i * sizeof (rtx));
3057 for (a = actuals, i = 0; a; a = TREE_CHAIN (a), i++)
3058 argvec[i] = expand_expr (TREE_VALUE (a), NULL_RTX, VOIDmode, 0);
3060 /* Find which actual values refer to current values of previous formals.
3061 Copy each of them now, before any formal is changed. */
3063 for (a = actuals, i = 0; a; a = TREE_CHAIN (a), i++)
3067 for (f = formals, j = 0; j < i; f = TREE_CHAIN (f), j++)
3068 if (reg_mentioned_p (DECL_RTL (f), argvec[i]))
3069 { copy = 1; break; }
3071 argvec[i] = copy_to_reg (argvec[i]);
3074 /* Store the values of the actuals into the formals. */
3076 for (f = formals, a = actuals, i = 0; f;
3077 f = TREE_CHAIN (f), a = TREE_CHAIN (a), i++)
3079 if (GET_MODE (DECL_RTL (f)) == GET_MODE (argvec[i]))
3080 emit_move_insn (DECL_RTL (f), argvec[i]);
3082 convert_move (DECL_RTL (f), argvec[i],
3083 TREE_UNSIGNED (TREE_TYPE (TREE_VALUE (a))));
3090 /* Generate the RTL code for entering a binding contour.
3091 The variables are declared one by one, by calls to `expand_decl'.
3093 EXIT_FLAG is nonzero if this construct should be visible to
3094 `exit_something'. */
3097 expand_start_bindings (exit_flag)
3100 struct nesting *thisblock = ALLOC_NESTING ();
3101 rtx note = output_bytecode ? 0 : emit_note (NULL_PTR, NOTE_INSN_BLOCK_BEG);
3103 /* Make an entry on block_stack for the block we are entering. */
3105 thisblock->next = block_stack;
3106 thisblock->all = nesting_stack;
3107 thisblock->depth = ++nesting_depth;
3108 thisblock->data.block.stack_level = 0;
3109 thisblock->data.block.cleanups = 0;
3110 thisblock->data.block.function_call_count = 0;
3111 thisblock->data.block.exception_region = 0;
3112 thisblock->data.block.target_temp_slot_level = target_temp_slot_level;
3114 thisblock->data.block.conditional_code = 0;
3115 thisblock->data.block.last_unconditional_cleanup = note;
3116 thisblock->data.block.cleanup_ptr = &thisblock->data.block.cleanups;
3119 && !(block_stack->data.block.cleanups == NULL_TREE
3120 && block_stack->data.block.outer_cleanups == NULL_TREE))
3121 thisblock->data.block.outer_cleanups
3122 = tree_cons (NULL_TREE, block_stack->data.block.cleanups,
3123 block_stack->data.block.outer_cleanups);
3125 thisblock->data.block.outer_cleanups = 0;
3126 thisblock->data.block.label_chain = 0;
3127 thisblock->data.block.innermost_stack_block = stack_block_stack;
3128 thisblock->data.block.first_insn = note;
3129 thisblock->data.block.block_start_count = ++block_start_count;
3130 thisblock->exit_label = exit_flag ? gen_label_rtx () : 0;
3131 block_stack = thisblock;
3132 nesting_stack = thisblock;
3134 if (!output_bytecode)
3136 /* Make a new level for allocating stack slots. */
3141 /* Specify the scope of temporaries created by TARGET_EXPRs. Similar
3142 to CLEANUP_POINT_EXPR, but handles cases when a series of calls to
3143 expand_expr are made. After we end the region, we know that all
3144 space for all temporaries that were created by TARGET_EXPRs will be
3145 destroyed and their space freed for reuse. */
3148 expand_start_target_temps ()
3150 /* This is so that even if the result is preserved, the space
3151 allocated will be freed, as we know that it is no longer in use. */
3154 /* Start a new binding layer that will keep track of all cleanup
3155 actions to be performed. */
3156 expand_start_bindings (0);
3158 target_temp_slot_level = temp_slot_level;
3162 expand_end_target_temps ()
3164 expand_end_bindings (NULL_TREE, 0, 0);
3166 /* This is so that even if the result is preserved, the space
3167 allocated will be freed, as we know that it is no longer in use. */
3171 /* Mark top block of block_stack as an implicit binding for an
3172 exception region. This is used to prevent infinite recursion when
3173 ending a binding with expand_end_bindings. It is only ever called
3174 by expand_eh_region_start, as that it the only way to create a
3175 block stack for a exception region. */
3178 mark_block_as_eh_region ()
3180 block_stack->data.block.exception_region = 1;
3181 if (block_stack->next
3182 && block_stack->next->data.block.conditional_code)
3184 block_stack->data.block.conditional_code
3185 = block_stack->next->data.block.conditional_code;
3186 block_stack->data.block.last_unconditional_cleanup
3187 = block_stack->next->data.block.last_unconditional_cleanup;
3188 block_stack->data.block.cleanup_ptr
3189 = block_stack->next->data.block.cleanup_ptr;
3193 /* True if we are currently emitting insns in an area of output code
3194 that is controlled by a conditional expression. This is used by
3195 the cleanup handling code to generate conditional cleanup actions. */
3198 conditional_context ()
3200 return block_stack && block_stack->data.block.conditional_code;
3203 /* Mark top block of block_stack as not for an implicit binding for an
3204 exception region. This is only ever done by expand_eh_region_end
3205 to let expand_end_bindings know that it is being called explicitly
3206 to end the binding layer for just the binding layer associated with
3207 the exception region, otherwise expand_end_bindings would try and
3208 end all implicit binding layers for exceptions regions, and then
3209 one normal binding layer. */
3212 mark_block_as_not_eh_region ()
3214 block_stack->data.block.exception_region = 0;
3217 /* True if the top block of block_stack was marked as for an exception
3218 region by mark_block_as_eh_region. */
3223 return block_stack && block_stack->data.block.exception_region;
3226 /* Given a pointer to a BLOCK node, save a pointer to the most recently
3227 generated NOTE_INSN_BLOCK_END in the BLOCK_END_NOTE field of the given
3231 remember_end_note (block)
3232 register tree block;
3234 BLOCK_END_NOTE (block) = last_block_end_note;
3235 last_block_end_note = NULL_RTX;
3238 /* Generate RTL code to terminate a binding contour.
3239 VARS is the chain of VAR_DECL nodes
3240 for the variables bound in this contour.
3241 MARK_ENDS is nonzero if we should put a note at the beginning
3242 and end of this binding contour.
3244 DONT_JUMP_IN is nonzero if it is not valid to jump into this contour.
3245 (That is true automatically if the contour has a saved stack level.) */
3248 expand_end_bindings (vars, mark_ends, dont_jump_in)
3253 register struct nesting *thisblock;
3256 while (block_stack->data.block.exception_region)
3258 /* Because we don't need or want a new temporary level and
3259 because we didn't create one in expand_eh_region_start,
3260 create a fake one now to avoid removing one in
3261 expand_end_bindings. */
3264 block_stack->data.block.exception_region = 0;
3266 expand_end_bindings (NULL_TREE, 0, 0);
3269 if (output_bytecode)
3271 bc_expand_end_bindings (vars, mark_ends, dont_jump_in);
3275 /* Since expand_eh_region_start does an expand_start_bindings, we
3276 have to first end all the bindings that were created by
3277 expand_eh_region_start. */
3279 thisblock = block_stack;
3282 for (decl = vars; decl; decl = TREE_CHAIN (decl))
3283 if (! TREE_USED (decl) && TREE_CODE (decl) == VAR_DECL
3284 && ! DECL_IN_SYSTEM_HEADER (decl)
3285 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
3286 warning_with_decl (decl, "unused variable `%s'");
3288 if (thisblock->exit_label)
3290 do_pending_stack_adjust ();
3291 emit_label (thisblock->exit_label);
3294 /* If necessary, make a handler for nonlocal gotos taking
3295 place in the function calls in this block. */
3296 if (function_call_count != thisblock->data.block.function_call_count
3298 /* Make handler for outermost block
3299 if there were any nonlocal gotos to this function. */
3300 && (thisblock->next == 0 ? current_function_has_nonlocal_label
3301 /* Make handler for inner block if it has something
3302 special to do when you jump out of it. */
3303 : (thisblock->data.block.cleanups != 0
3304 || thisblock->data.block.stack_level != 0)))
3307 rtx afterward = gen_label_rtx ();
3308 rtx handler_label = gen_label_rtx ();
3309 rtx save_receiver = gen_reg_rtx (Pmode);
3312 /* Don't let jump_optimize delete the handler. */
3313 LABEL_PRESERVE_P (handler_label) = 1;
3315 /* Record the handler address in the stack slot for that purpose,
3316 during this block, saving and restoring the outer value. */
3317 if (thisblock->next != 0)
3319 emit_move_insn (nonlocal_goto_handler_slot, save_receiver);
3322 emit_move_insn (save_receiver, nonlocal_goto_handler_slot);
3323 insns = get_insns ();
3325 emit_insns_before (insns, thisblock->data.block.first_insn);
3329 emit_move_insn (nonlocal_goto_handler_slot,
3330 gen_rtx (LABEL_REF, Pmode, handler_label));
3331 insns = get_insns ();
3333 emit_insns_before (insns, thisblock->data.block.first_insn);
3335 /* Jump around the handler; it runs only when specially invoked. */
3336 emit_jump (afterward);
3337 emit_label (handler_label);
3339 #ifdef HAVE_nonlocal_goto
3340 if (! HAVE_nonlocal_goto)
3342 /* First adjust our frame pointer to its actual value. It was
3343 previously set to the start of the virtual area corresponding to
3344 the stacked variables when we branched here and now needs to be
3345 adjusted to the actual hardware fp value.
3347 Assignments are to virtual registers are converted by
3348 instantiate_virtual_regs into the corresponding assignment
3349 to the underlying register (fp in this case) that makes
3350 the original assignment true.
3351 So the following insn will actually be
3352 decrementing fp by STARTING_FRAME_OFFSET. */
3353 emit_move_insn (virtual_stack_vars_rtx, hard_frame_pointer_rtx);
3355 #if ARG_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
3356 if (fixed_regs[ARG_POINTER_REGNUM])
3358 #ifdef ELIMINABLE_REGS
3359 /* If the argument pointer can be eliminated in favor of the
3360 frame pointer, we don't need to restore it. We assume here
3361 that if such an elimination is present, it can always be used.
3362 This is the case on all known machines; if we don't make this
3363 assumption, we do unnecessary saving on many machines. */
3364 static struct elims {int from, to;} elim_regs[] = ELIMINABLE_REGS;
3367 for (i = 0; i < sizeof elim_regs / sizeof elim_regs[0]; i++)
3368 if (elim_regs[i].from == ARG_POINTER_REGNUM
3369 && elim_regs[i].to == HARD_FRAME_POINTER_REGNUM)
3372 if (i == sizeof elim_regs / sizeof elim_regs [0])
3375 /* Now restore our arg pointer from the address at which it
3376 was saved in our stack frame.
3377 If there hasn't be space allocated for it yet, make
3379 if (arg_pointer_save_area == 0)
3380 arg_pointer_save_area
3381 = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
3382 emit_move_insn (virtual_incoming_args_rtx,
3383 /* We need a pseudo here, or else
3384 instantiate_virtual_regs_1 complains. */
3385 copy_to_reg (arg_pointer_save_area));
3390 #ifdef HAVE_nonlocal_goto_receiver
3391 if (HAVE_nonlocal_goto_receiver)
3392 emit_insn (gen_nonlocal_goto_receiver ());
3395 /* The handler expects the desired label address in the static chain
3396 register. It tests the address and does an appropriate jump
3397 to whatever label is desired. */
3398 for (link = nonlocal_labels; link; link = TREE_CHAIN (link))
3399 /* Skip any labels we shouldn't be able to jump to from here. */
3400 if (! DECL_TOO_LATE (TREE_VALUE (link)))
3402 rtx not_this = gen_label_rtx ();
3403 rtx this = gen_label_rtx ();
3404 do_jump_if_equal (static_chain_rtx,
3405 gen_rtx (LABEL_REF, Pmode, DECL_RTL (TREE_VALUE (link))),
3407 emit_jump (not_this);
3409 expand_goto (TREE_VALUE (link));
3410 emit_label (not_this);
3412 /* If label is not recognized, abort. */
3413 emit_library_call (gen_rtx (SYMBOL_REF, Pmode, "abort"), 0,
3416 emit_label (afterward);
3419 /* Don't allow jumping into a block that has a stack level.
3420 Cleanups are allowed, though. */
3422 || thisblock->data.block.stack_level != 0)
3424 struct label_chain *chain;
3426 /* Any labels in this block are no longer valid to go to.
3427 Mark them to cause an error message. */
3428 for (chain = thisblock->data.block.label_chain; chain; chain = chain->next)
3430 DECL_TOO_LATE (chain->label) = 1;
3431 /* If any goto without a fixup came to this label,
3432 that must be an error, because gotos without fixups
3433 come from outside all saved stack-levels. */
3434 if (TREE_ADDRESSABLE (chain->label))
3435 error_with_decl (chain->label,
3436 "label `%s' used before containing binding contour");
3440 /* Restore stack level in effect before the block
3441 (only if variable-size objects allocated). */
3442 /* Perform any cleanups associated with the block. */
3444 if (thisblock->data.block.stack_level != 0
3445 || thisblock->data.block.cleanups != 0)
3447 /* Only clean up here if this point can actually be reached. */
3448 int reachable = GET_CODE (get_last_insn ()) != BARRIER;
3450 /* Don't let cleanups affect ({...}) constructs. */
3451 int old_expr_stmts_for_value = expr_stmts_for_value;
3452 rtx old_last_expr_value = last_expr_value;
3453 tree old_last_expr_type = last_expr_type;
3454 expr_stmts_for_value = 0;
3456 /* Do the cleanups. */
3457 expand_cleanups (thisblock->data.block.cleanups, NULL_TREE, 0, reachable);
3459 do_pending_stack_adjust ();
3461 expr_stmts_for_value = old_expr_stmts_for_value;
3462 last_expr_value = old_last_expr_value;
3463 last_expr_type = old_last_expr_type;
3465 /* Restore the stack level. */
3467 if (reachable && thisblock->data.block.stack_level != 0)
3469 emit_stack_restore (thisblock->next ? SAVE_BLOCK : SAVE_FUNCTION,
3470 thisblock->data.block.stack_level, NULL_RTX);
3471 if (nonlocal_goto_handler_slot != 0)
3472 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level,
3476 /* Any gotos out of this block must also do these things.
3477 Also report any gotos with fixups that came to labels in this
3479 fixup_gotos (thisblock,
3480 thisblock->data.block.stack_level,
3481 thisblock->data.block.cleanups,
3482 thisblock->data.block.first_insn,
3486 /* Mark the beginning and end of the scope if requested.
3487 We do this now, after running cleanups on the variables
3488 just going out of scope, so they are in scope for their cleanups. */
3491 last_block_end_note = emit_note (NULL_PTR, NOTE_INSN_BLOCK_END);
3493 /* Get rid of the beginning-mark if we don't make an end-mark. */
3494 NOTE_LINE_NUMBER (thisblock->data.block.first_insn) = NOTE_INSN_DELETED;
3496 /* If doing stupid register allocation, make sure lives of all
3497 register variables declared here extend thru end of scope. */
3500 for (decl = vars; decl; decl = TREE_CHAIN (decl))
3502 rtx rtl = DECL_RTL (decl);
3503 if (TREE_CODE (decl) == VAR_DECL && rtl != 0)
3507 /* Restore the temporary level of TARGET_EXPRs. */
3508 target_temp_slot_level = thisblock->data.block.target_temp_slot_level;
3510 /* Restore block_stack level for containing block. */
3512 stack_block_stack = thisblock->data.block.innermost_stack_block;
3513 POPSTACK (block_stack);
3515 /* Pop the stack slot nesting and free any slots at this level. */
3520 /* End a binding contour.
3521 VARS is the chain of VAR_DECL nodes for the variables bound
3522 in this contour. MARK_ENDS is nonzer if we should put a note
3523 at the beginning and end of this binding contour.
3524 DONT_JUMP_IN is nonzero if it is not valid to jump into this
3528 bc_expand_end_bindings (vars, mark_ends, dont_jump_in)
3533 struct nesting *thisbind = nesting_stack;
3537 for (decl = vars; decl; decl = TREE_CHAIN (decl))
3538 if (! TREE_USED (TREE_VALUE (decl)) && TREE_CODE (TREE_VALUE (decl)) == VAR_DECL)
3539 warning_with_decl (decl, "unused variable `%s'");
3541 if (thisbind->exit_label)
3542 bc_emit_bytecode_labeldef (BYTECODE_BC_LABEL (thisbind->exit_label));
3544 /* Pop block/bindings off stack */
3545 POPSTACK (block_stack);
3548 /* Generate RTL for the automatic variable declaration DECL.
3549 (Other kinds of declarations are simply ignored if seen here.) */
3555 struct nesting *thisblock = block_stack;
3558 if (output_bytecode)
3560 bc_expand_decl (decl, 0);
3564 type = TREE_TYPE (decl);
3566 /* Only automatic variables need any expansion done.
3567 Static and external variables, and external functions,
3568 will be handled by `assemble_variable' (called from finish_decl).
3569 TYPE_DECL and CONST_DECL require nothing.
3570 PARM_DECLs are handled in `assign_parms'. */
3572 if (TREE_CODE (decl) != VAR_DECL)
3574 if (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
3577 /* Create the RTL representation for the variable. */
3579 if (type == error_mark_node)
3580 DECL_RTL (decl) = gen_rtx (MEM, BLKmode, const0_rtx);
3581 else if (DECL_SIZE (decl) == 0)
3582 /* Variable with incomplete type. */
3584 if (DECL_INITIAL (decl) == 0)
3585 /* Error message was already done; now avoid a crash. */
3586 DECL_RTL (decl) = assign_stack_temp (DECL_MODE (decl), 0, 1);
3588 /* An initializer is going to decide the size of this array.
3589 Until we know the size, represent its address with a reg. */
3590 DECL_RTL (decl) = gen_rtx (MEM, BLKmode, gen_reg_rtx (Pmode));
3591 MEM_IN_STRUCT_P (DECL_RTL (decl)) = AGGREGATE_TYPE_P (type);
3593 else if (DECL_MODE (decl) != BLKmode
3594 /* If -ffloat-store, don't put explicit float vars
3596 && !(flag_float_store
3597 && TREE_CODE (type) == REAL_TYPE)
3598 && ! TREE_THIS_VOLATILE (decl)
3599 && ! TREE_ADDRESSABLE (decl)
3600 && (DECL_REGISTER (decl) || ! obey_regdecls))
3602 /* Automatic variable that can go in a register. */
3603 int unsignedp = TREE_UNSIGNED (type);
3604 enum machine_mode reg_mode
3605 = promote_mode (type, DECL_MODE (decl), &unsignedp, 0);
3607 DECL_RTL (decl) = gen_reg_rtx (reg_mode);
3608 mark_user_reg (DECL_RTL (decl));
3610 if (TREE_CODE (type) == POINTER_TYPE)
3611 mark_reg_pointer (DECL_RTL (decl),
3612 (TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl)))
3616 else if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST
3617 && ! (flag_stack_check && ! STACK_CHECK_BUILTIN
3618 && (TREE_INT_CST_HIGH (DECL_SIZE (decl)) != 0
3619 || (TREE_INT_CST_LOW (DECL_SIZE (decl))
3620 > STACK_CHECK_MAX_VAR_SIZE * BITS_PER_UNIT))))
3622 /* Variable of fixed size that goes on the stack. */
3626 /* If we previously made RTL for this decl, it must be an array
3627 whose size was determined by the initializer.
3628 The old address was a register; set that register now
3629 to the proper address. */
3630 if (DECL_RTL (decl) != 0)
3632 if (GET_CODE (DECL_RTL (decl)) != MEM
3633 || GET_CODE (XEXP (DECL_RTL (decl), 0)) != REG)
3635 oldaddr = XEXP (DECL_RTL (decl), 0);
3639 = assign_stack_temp (DECL_MODE (decl),
3640 ((TREE_INT_CST_LOW (DECL_SIZE (decl))
3641 + BITS_PER_UNIT - 1)
3644 MEM_IN_STRUCT_P (DECL_RTL (decl)) = AGGREGATE_TYPE_P (TREE_TYPE (decl));
3646 /* Set alignment we actually gave this decl. */
3647 DECL_ALIGN (decl) = (DECL_MODE (decl) == BLKmode ? BIGGEST_ALIGNMENT
3648 : GET_MODE_BITSIZE (DECL_MODE (decl)));
3652 addr = force_operand (XEXP (DECL_RTL (decl), 0), oldaddr);
3653 if (addr != oldaddr)
3654 emit_move_insn (oldaddr, addr);
3657 /* If this is a memory ref that contains aggregate components,
3658 mark it as such for cse and loop optimize. */
3659 MEM_IN_STRUCT_P (DECL_RTL (decl)) = AGGREGATE_TYPE_P (TREE_TYPE (decl));
3661 /* If this is in memory because of -ffloat-store,
3662 set the volatile bit, to prevent optimizations from
3663 undoing the effects. */
3664 if (flag_float_store && TREE_CODE (type) == REAL_TYPE)
3665 MEM_VOLATILE_P (DECL_RTL (decl)) = 1;
3669 /* Dynamic-size object: must push space on the stack. */
3673 /* Record the stack pointer on entry to block, if have
3674 not already done so. */
3675 if (thisblock->data.block.stack_level == 0)
3677 do_pending_stack_adjust ();
3678 emit_stack_save (thisblock->next ? SAVE_BLOCK : SAVE_FUNCTION,
3679 &thisblock->data.block.stack_level,
3680 thisblock->data.block.first_insn);
3681 stack_block_stack = thisblock;
3684 /* Compute the variable's size, in bytes. */
3685 size = expand_expr (size_binop (CEIL_DIV_EXPR,
3687 size_int (BITS_PER_UNIT)),
3688 NULL_RTX, VOIDmode, 0);
3691 /* Allocate space on the stack for the variable. Note that
3692 DECL_ALIGN says how the variable is to be aligned and we
3693 cannot use it to conclude anything about the alignment of
3695 address = allocate_dynamic_stack_space (size, NULL_RTX,
3696 TYPE_ALIGN (TREE_TYPE (decl)));
3698 /* Reference the variable indirect through that rtx. */
3699 DECL_RTL (decl) = gen_rtx (MEM, DECL_MODE (decl), address);
3701 /* If this is a memory ref that contains aggregate components,
3702 mark it as such for cse and loop optimize. */
3703 MEM_IN_STRUCT_P (DECL_RTL (decl)) = AGGREGATE_TYPE_P (TREE_TYPE (decl));
3705 /* Indicate the alignment we actually gave this variable. */
3706 #ifdef STACK_BOUNDARY
3707 DECL_ALIGN (decl) = STACK_BOUNDARY;
3709 DECL_ALIGN (decl) = BIGGEST_ALIGNMENT;
3713 if (TREE_THIS_VOLATILE (decl))
3714 MEM_VOLATILE_P (DECL_RTL (decl)) = 1;
3715 #if 0 /* A variable is not necessarily unchanging
3716 just because it is const. RTX_UNCHANGING_P
3717 means no change in the function,
3718 not merely no change in the variable's scope.
3719 It is correct to set RTX_UNCHANGING_P if the variable's scope
3720 is the whole function. There's no convenient way to test that. */
3721 if (TREE_READONLY (decl))
3722 RTX_UNCHANGING_P (DECL_RTL (decl)) = 1;
3725 /* If doing stupid register allocation, make sure life of any
3726 register variable starts here, at the start of its scope. */
3729 use_variable (DECL_RTL (decl));
3733 /* Generate code for the automatic variable declaration DECL. For
3734 most variables this just means we give it a stack offset. The
3735 compiler sometimes emits cleanups without variables and we will
3736 have to deal with those too. */
3739 bc_expand_decl (decl, cleanup)
3747 /* A cleanup with no variable. */
3754 /* Only auto variables need any work. */
3755 if (TREE_CODE (decl) != VAR_DECL || TREE_STATIC (decl) || DECL_EXTERNAL (decl))
3758 type = TREE_TYPE (decl);
3760 if (type == error_mark_node)
3761 DECL_RTL (decl) = bc_gen_rtx ((char *) 0, 0, (struct bc_label *) 0);
3763 else if (DECL_SIZE (decl) == 0)
3765 /* Variable with incomplete type. The stack offset herein will be
3766 fixed later in expand_decl_init. */
3767 DECL_RTL (decl) = bc_gen_rtx ((char *) 0, 0, (struct bc_label *) 0);
3769 else if (TREE_CONSTANT (DECL_SIZE (decl)))
3771 DECL_RTL (decl) = bc_allocate_local (TREE_INT_CST_LOW (DECL_SIZE (decl)) / BITS_PER_UNIT,
3775 DECL_RTL (decl) = bc_allocate_variable_array (DECL_SIZE (decl));
3778 /* Emit code to perform the initialization of a declaration DECL. */
3781 expand_decl_init (decl)
3784 int was_used = TREE_USED (decl);
3786 if (output_bytecode)
3788 bc_expand_decl_init (decl);
3792 /* If this is a CONST_DECL, we don't have to generate any code, but
3793 if DECL_INITIAL is a constant, call expand_expr to force TREE_CST_RTL
3794 to be set while in the obstack containing the constant. If we don't
3795 do this, we can lose if we have functions nested three deep and the middle
3796 function makes a CONST_DECL whose DECL_INITIAL is a STRING_CST while
3797 the innermost function is the first to expand that STRING_CST. */
3798 if (TREE_CODE (decl) == CONST_DECL)
3800 if (DECL_INITIAL (decl) && TREE_CONSTANT (DECL_INITIAL (decl)))
3801 expand_expr (DECL_INITIAL (decl), NULL_RTX, VOIDmode,
3802 EXPAND_INITIALIZER);
3806 if (TREE_STATIC (decl))
3809 /* Compute and store the initial value now. */
3811 if (DECL_INITIAL (decl) == error_mark_node)
3813 enum tree_code code = TREE_CODE (TREE_TYPE (decl));
3814 if (code == INTEGER_TYPE || code == REAL_TYPE || code == ENUMERAL_TYPE
3815 || code == POINTER_TYPE)
3816 expand_assignment (decl, convert (TREE_TYPE (decl), integer_zero_node),
3820 else if (DECL_INITIAL (decl) && TREE_CODE (DECL_INITIAL (decl)) != TREE_LIST)
3822 emit_line_note (DECL_SOURCE_FILE (decl), DECL_SOURCE_LINE (decl));
3823 expand_assignment (decl, DECL_INITIAL (decl), 0, 0);
3827 /* Don't let the initialization count as "using" the variable. */
3828 TREE_USED (decl) = was_used;
3830 /* Free any temporaries we made while initializing the decl. */
3831 preserve_temp_slots (NULL_RTX);
3835 /* Expand initialization for variable-sized types. Allocate array
3836 using newlocalSI and set local variable, which is a pointer to the
3840 bc_expand_variable_local_init (decl)
3843 /* Evaluate size expression and coerce to SI */
3844 bc_expand_expr (DECL_SIZE (decl));
3846 /* Type sizes are always (?) of TREE_CODE INTEGER_CST, so
3847 no coercion is necessary (?) */
3849 /* emit_typecode_conversion (preferred_typecode (TYPE_MODE (DECL_SIZE (decl)),
3850 TREE_UNSIGNED (DECL_SIZE (decl))), SIcode); */
3852 /* Emit code to allocate array */
3853 bc_emit_instruction (newlocalSI);
3855 /* Store array pointer in local variable. This is the only instance
3856 where we actually want the address of the pointer to the
3857 variable-size block, rather than the pointer itself. We avoid
3858 using expand_address() since that would cause the pointer to be
3859 pushed rather than its address. Hence the hard-coded reference;
3860 notice also that the variable is always local (no global
3861 variable-size type variables). */
3863 bc_load_localaddr (DECL_RTL (decl));
3864 bc_emit_instruction (storeP);
3868 /* Emit code to initialize a declaration. */
3871 bc_expand_decl_init (decl)
3874 int org_stack_depth;
3876 /* Statical initializers are handled elsewhere */
3878 if (TREE_STATIC (decl))
3881 /* Memory original stack depth */
3882 org_stack_depth = stack_depth;
3884 /* If the type is variable-size, we first create its space (we ASSUME
3885 it CAN'T be static). We do this regardless of whether there's an
3886 initializer assignment or not. */
3888 if (TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST)
3889 bc_expand_variable_local_init (decl);
3891 /* Expand initializer assignment */
3892 if (DECL_INITIAL (decl) == error_mark_node)
3894 enum tree_code code = TREE_CODE (TREE_TYPE (decl));
3896 if (code == INTEGER_TYPE || code == REAL_TYPE || code == ENUMERAL_TYPE
3897 || code == POINTER_TYPE)
3899 expand_assignment (TREE_TYPE (decl), decl, 0, 0);
3901 else if (DECL_INITIAL (decl))
3902 expand_assignment (TREE_TYPE (decl), decl, 0, 0);
3904 /* Restore stack depth */
3905 if (org_stack_depth > stack_depth)
3908 bc_adjust_stack (stack_depth - org_stack_depth);
3912 /* CLEANUP is an expression to be executed at exit from this binding contour;
3913 for example, in C++, it might call the destructor for this variable.
3915 We wrap CLEANUP in an UNSAVE_EXPR node, so that we can expand the
3916 CLEANUP multiple times, and have the correct semantics. This
3917 happens in exception handling, for gotos, returns, breaks that
3918 leave the current scope.
3920 If CLEANUP is nonzero and DECL is zero, we record a cleanup
3921 that is not associated with any particular variable. */
3924 expand_decl_cleanup (decl, cleanup)
3927 struct nesting *thisblock = block_stack;
3929 /* Error if we are not in any block. */
3933 /* Record the cleanup if there is one. */
3939 tree *cleanups = &thisblock->data.block.cleanups;
3940 int cond_context = conditional_context ();
3944 rtx flag = gen_reg_rtx (word_mode);
3949 emit_move_insn (flag, const0_rtx);
3950 set_flag_0 = get_insns ();
3953 thisblock->data.block.last_unconditional_cleanup
3954 = emit_insns_after (set_flag_0,
3955 thisblock->data.block.last_unconditional_cleanup);
3957 emit_move_insn (flag, const1_rtx);
3959 /* All cleanups must be on the function_obstack. */
3960 push_obstacks_nochange ();
3961 resume_temporary_allocation ();
3963 cond = build_decl (VAR_DECL, NULL_TREE, type_for_mode (word_mode, 1));
3964 DECL_RTL (cond) = flag;
3966 /* Conditionalize the cleanup. */
3967 cleanup = build (COND_EXPR, void_type_node,
3968 truthvalue_conversion (cond),
3969 cleanup, integer_zero_node);
3970 cleanup = fold (cleanup);
3974 cleanups = thisblock->data.block.cleanup_ptr;
3977 /* All cleanups must be on the function_obstack. */
3978 push_obstacks_nochange ();
3979 resume_temporary_allocation ();
3980 cleanup = unsave_expr (cleanup);
3983 t = *cleanups = temp_tree_cons (decl, cleanup, *cleanups);
3986 /* If this block has a cleanup, it belongs in stack_block_stack. */
3987 stack_block_stack = thisblock;
3994 /* If this was optimized so that there is no exception region for the
3995 cleanup, then mark the TREE_LIST node, so that we can later tell
3996 if we need to call expand_eh_region_end. */
3997 if (! using_eh_for_cleanups_p
3998 || expand_eh_region_start_tree (decl, cleanup))
3999 TREE_ADDRESSABLE (t) = 1;
4000 /* If that started a new EH region, we're in a new block. */
4001 thisblock = block_stack;
4008 thisblock->data.block.last_unconditional_cleanup
4009 = emit_insns_after (seq,
4010 thisblock->data.block.last_unconditional_cleanup);
4014 thisblock->data.block.last_unconditional_cleanup
4016 thisblock->data.block.cleanup_ptr = &thisblock->data.block.cleanups;
4022 /* Like expand_decl_cleanup, but suppress generating an exception handler
4023 to perform the cleanup. */
4026 expand_decl_cleanup_no_eh (decl, cleanup)
4029 int save_eh = using_eh_for_cleanups_p;
4030 using_eh_for_cleanups_p = 0;
4031 expand_decl_cleanup (decl, cleanup);
4032 using_eh_for_cleanups_p = save_eh;
4035 /* Arrange for the top element of the dynamic cleanup chain to be
4036 popped if we exit the current binding contour. DECL is the
4037 associated declaration, if any, otherwise NULL_TREE. If the
4038 current contour is left via an exception, then __sjthrow will pop
4039 the top element off the dynamic cleanup chain. The code that
4040 avoids doing the action we push into the cleanup chain in the
4041 exceptional case is contained in expand_cleanups.
4043 This routine is only used by expand_eh_region_start, and that is
4044 the only way in which an exception region should be started. This
4045 routine is only used when using the setjmp/longjmp codegen method
4046 for exception handling. */
4049 expand_dcc_cleanup (decl)
4052 struct nesting *thisblock = block_stack;
4055 /* Error if we are not in any block. */
4059 /* Record the cleanup for the dynamic handler chain. */
4061 /* All cleanups must be on the function_obstack. */
4062 push_obstacks_nochange ();
4063 resume_temporary_allocation ();
4064 cleanup = make_node (POPDCC_EXPR);
4067 /* Add the cleanup in a manner similar to expand_decl_cleanup. */
4068 thisblock->data.block.cleanups
4069 = temp_tree_cons (decl, cleanup, thisblock->data.block.cleanups);
4071 /* If this block has a cleanup, it belongs in stack_block_stack. */
4072 stack_block_stack = thisblock;
4076 /* Arrange for the top element of the dynamic handler chain to be
4077 popped if we exit the current binding contour. DECL is the
4078 associated declaration, if any, otherwise NULL_TREE. If the current
4079 contour is left via an exception, then __sjthrow will pop the top
4080 element off the dynamic handler chain. The code that avoids doing
4081 the action we push into the handler chain in the exceptional case
4082 is contained in expand_cleanups.
4084 This routine is only used by expand_eh_region_start, and that is
4085 the only way in which an exception region should be started. This
4086 routine is only used when using the setjmp/longjmp codegen method
4087 for exception handling. */
4090 expand_dhc_cleanup (decl)
4093 struct nesting *thisblock = block_stack;
4096 /* Error if we are not in any block. */
4100 /* Record the cleanup for the dynamic handler chain. */
4102 /* All cleanups must be on the function_obstack. */
4103 push_obstacks_nochange ();
4104 resume_temporary_allocation ();
4105 cleanup = make_node (POPDHC_EXPR);
4108 /* Add the cleanup in a manner similar to expand_decl_cleanup. */
4109 thisblock->data.block.cleanups
4110 = temp_tree_cons (decl, cleanup, thisblock->data.block.cleanups);
4112 /* If this block has a cleanup, it belongs in stack_block_stack. */
4113 stack_block_stack = thisblock;
4117 /* DECL is an anonymous union. CLEANUP is a cleanup for DECL.
4118 DECL_ELTS is the list of elements that belong to DECL's type.
4119 In each, the TREE_VALUE is a VAR_DECL, and the TREE_PURPOSE a cleanup. */
4122 expand_anon_union_decl (decl, cleanup, decl_elts)
4123 tree decl, cleanup, decl_elts;
4125 struct nesting *thisblock = block_stack;
4129 expand_decl_cleanup (decl, cleanup);
4130 x = DECL_RTL (decl);
4134 tree decl_elt = TREE_VALUE (decl_elts);
4135 tree cleanup_elt = TREE_PURPOSE (decl_elts);
4136 enum machine_mode mode = TYPE_MODE (TREE_TYPE (decl_elt));
4138 /* Propagate the union's alignment to the elements. */
4139 DECL_ALIGN (decl_elt) = DECL_ALIGN (decl);
4141 /* If the element has BLKmode and the union doesn't, the union is
4142 aligned such that the element doesn't need to have BLKmode, so
4143 change the element's mode to the appropriate one for its size. */
4144 if (mode == BLKmode && DECL_MODE (decl) != BLKmode)
4145 DECL_MODE (decl_elt) = mode
4146 = mode_for_size (TREE_INT_CST_LOW (DECL_SIZE (decl_elt)),
4149 /* (SUBREG (MEM ...)) at RTL generation time is invalid, so we
4150 instead create a new MEM rtx with the proper mode. */
4151 if (GET_CODE (x) == MEM)
4153 if (mode == GET_MODE (x))
4154 DECL_RTL (decl_elt) = x;
4157 DECL_RTL (decl_elt) = gen_rtx (MEM, mode, copy_rtx (XEXP (x, 0)));
4158 MEM_IN_STRUCT_P (DECL_RTL (decl_elt)) = MEM_IN_STRUCT_P (x);
4159 RTX_UNCHANGING_P (DECL_RTL (decl_elt)) = RTX_UNCHANGING_P (x);
4162 else if (GET_CODE (x) == REG)
4164 if (mode == GET_MODE (x))
4165 DECL_RTL (decl_elt) = x;
4167 DECL_RTL (decl_elt) = gen_rtx (SUBREG, mode, x, 0);
4172 /* Record the cleanup if there is one. */
4175 thisblock->data.block.cleanups
4176 = temp_tree_cons (decl_elt, cleanup_elt,
4177 thisblock->data.block.cleanups);
4179 decl_elts = TREE_CHAIN (decl_elts);
4183 /* Expand a list of cleanups LIST.
4184 Elements may be expressions or may be nested lists.
4186 If DONT_DO is nonnull, then any list-element
4187 whose TREE_PURPOSE matches DONT_DO is omitted.
4188 This is sometimes used to avoid a cleanup associated with
4189 a value that is being returned out of the scope.
4191 If IN_FIXUP is non-zero, we are generating this cleanup for a fixup
4192 goto and handle protection regions specially in that case.
4194 If REACHABLE, we emit code, otherwise just inform the exception handling
4195 code about this finalization. */
4198 expand_cleanups (list, dont_do, in_fixup, reachable)
4205 for (tail = list; tail; tail = TREE_CHAIN (tail))
4206 if (dont_do == 0 || TREE_PURPOSE (tail) != dont_do)
4208 if (TREE_CODE (TREE_VALUE (tail)) == TREE_LIST)
4209 expand_cleanups (TREE_VALUE (tail), dont_do, in_fixup, reachable);
4214 tree cleanup = TREE_VALUE (tail);
4216 /* See expand_d{h,c}c_cleanup for why we avoid this. */
4217 if (TREE_CODE (cleanup) != POPDHC_EXPR
4218 && TREE_CODE (cleanup) != POPDCC_EXPR
4219 /* See expand_eh_region_start_tree for this case. */
4220 && ! TREE_ADDRESSABLE (tail))
4222 cleanup = protect_with_terminate (cleanup);
4223 expand_eh_region_end (cleanup);
4229 /* Cleanups may be run multiple times. For example,
4230 when exiting a binding contour, we expand the
4231 cleanups associated with that contour. When a goto
4232 within that binding contour has a target outside that
4233 contour, it will expand all cleanups from its scope to
4234 the target. Though the cleanups are expanded multiple
4235 times, the control paths are non-overlapping so the
4236 cleanups will not be executed twice. */
4238 /* We may need to protect fixups with rethrow regions. */
4239 int protect = (in_fixup && ! TREE_ADDRESSABLE (tail));
4241 expand_fixup_region_start ();
4242 expand_expr (TREE_VALUE (tail), const0_rtx, VOIDmode, 0);
4244 expand_fixup_region_end (TREE_VALUE (tail));
4251 /* Mark when the context we are emitting RTL for as a conditional
4252 context, so that any cleanup actions we register with
4253 expand_decl_init will be properly conditionalized when those
4254 cleanup actions are later performed. Must be called before any
4255 expression (tree) is expanded that is within a conditional context. */
4258 start_cleanup_deferral ()
4260 /* block_stack can be NULL if we are inside the parameter list. It is
4261 OK to do nothing, because cleanups aren't possible here. */
4263 ++block_stack->data.block.conditional_code;
4266 /* Mark the end of a conditional region of code. Because cleanup
4267 deferrals may be nested, we may still be in a conditional region
4268 after we end the currently deferred cleanups, only after we end all
4269 deferred cleanups, are we back in unconditional code. */
4272 end_cleanup_deferral ()
4274 /* block_stack can be NULL if we are inside the parameter list. It is
4275 OK to do nothing, because cleanups aren't possible here. */
4277 --block_stack->data.block.conditional_code;
4280 /* Move all cleanups from the current block_stack
4281 to the containing block_stack, where they are assumed to
4282 have been created. If anything can cause a temporary to
4283 be created, but not expanded for more than one level of
4284 block_stacks, then this code will have to change. */
4289 struct nesting *block = block_stack;
4290 struct nesting *outer = block->next;
4292 outer->data.block.cleanups
4293 = chainon (block->data.block.cleanups,
4294 outer->data.block.cleanups);
4295 block->data.block.cleanups = 0;
4299 last_cleanup_this_contour ()
4301 if (block_stack == 0)
4304 return block_stack->data.block.cleanups;
4307 /* Return 1 if there are any pending cleanups at this point.
4308 If THIS_CONTOUR is nonzero, check the current contour as well.
4309 Otherwise, look only at the contours that enclose this one. */
4312 any_pending_cleanups (this_contour)
4315 struct nesting *block;
4317 if (block_stack == 0)
4320 if (this_contour && block_stack->data.block.cleanups != NULL)
4322 if (block_stack->data.block.cleanups == 0
4323 && block_stack->data.block.outer_cleanups == 0)
4326 for (block = block_stack->next; block; block = block->next)
4327 if (block->data.block.cleanups != 0)
4333 /* Enter a case (Pascal) or switch (C) statement.
4334 Push a block onto case_stack and nesting_stack
4335 to accumulate the case-labels that are seen
4336 and to record the labels generated for the statement.
4338 EXIT_FLAG is nonzero if `exit_something' should exit this case stmt.
4339 Otherwise, this construct is transparent for `exit_something'.
4341 EXPR is the index-expression to be dispatched on.
4342 TYPE is its nominal type. We could simply convert EXPR to this type,
4343 but instead we take short cuts. */
4346 expand_start_case (exit_flag, expr, type, printname)
4352 register struct nesting *thiscase = ALLOC_NESTING ();
4354 /* Make an entry on case_stack for the case we are entering. */
4356 thiscase->next = case_stack;
4357 thiscase->all = nesting_stack;
4358 thiscase->depth = ++nesting_depth;
4359 thiscase->exit_label = exit_flag ? gen_label_rtx () : 0;
4360 thiscase->data.case_stmt.case_list = 0;
4361 thiscase->data.case_stmt.index_expr = expr;
4362 thiscase->data.case_stmt.nominal_type = type;
4363 thiscase->data.case_stmt.default_label = 0;
4364 thiscase->data.case_stmt.num_ranges = 0;
4365 thiscase->data.case_stmt.printname = printname;
4366 thiscase->data.case_stmt.seenlabel = 0;
4367 case_stack = thiscase;
4368 nesting_stack = thiscase;
4370 if (output_bytecode)
4372 bc_expand_start_case (thiscase, expr, type, printname);
4376 do_pending_stack_adjust ();
4378 /* Make sure case_stmt.start points to something that won't
4379 need any transformation before expand_end_case. */
4380 if (GET_CODE (get_last_insn ()) != NOTE)
4381 emit_note (NULL_PTR, NOTE_INSN_DELETED);
4383 thiscase->data.case_stmt.start = get_last_insn ();
4385 start_cleanup_deferral ();
4389 /* Enter a case statement. It is assumed that the caller has pushed
4390 the current context onto the case stack. */
4393 bc_expand_start_case (thiscase, expr, type, printname)
4394 struct nesting *thiscase;
4399 bc_expand_expr (expr);
4400 bc_expand_conversion (TREE_TYPE (expr), type);
4402 /* For cases, the skip is a place we jump to that's emitted after
4403 the size of the jump table is known. */
4405 thiscase->data.case_stmt.skip_label = gen_label_rtx ();
4406 bc_emit_bytecode (jump);
4407 bc_emit_bytecode_labelref (BYTECODE_BC_LABEL (thiscase->data.case_stmt.skip_label));
4409 #ifdef DEBUG_PRINT_CODE
4410 fputc ('\n', stderr);
4415 /* Start a "dummy case statement" within which case labels are invalid
4416 and are not connected to any larger real case statement.
4417 This can be used if you don't want to let a case statement jump
4418 into the middle of certain kinds of constructs. */
4421 expand_start_case_dummy ()
4423 register struct nesting *thiscase = ALLOC_NESTING ();
4425 /* Make an entry on case_stack for the dummy. */
4427 thiscase->next = case_stack;
4428 thiscase->all = nesting_stack;
4429 thiscase->depth = ++nesting_depth;
4430 thiscase->exit_label = 0;
4431 thiscase->data.case_stmt.case_list = 0;
4432 thiscase->data.case_stmt.start = 0;
4433 thiscase->data.case_stmt.nominal_type = 0;
4434 thiscase->data.case_stmt.default_label = 0;
4435 thiscase->data.case_stmt.num_ranges = 0;
4436 case_stack = thiscase;
4437 nesting_stack = thiscase;
4438 start_cleanup_deferral ();
4441 /* End a dummy case statement. */
4444 expand_end_case_dummy ()
4446 end_cleanup_deferral ();
4447 POPSTACK (case_stack);
4450 /* Return the data type of the index-expression
4451 of the innermost case statement, or null if none. */
4454 case_index_expr_type ()
4457 return TREE_TYPE (case_stack->data.case_stmt.index_expr);
4461 /* Accumulate one case or default label inside a case or switch statement.
4462 VALUE is the value of the case (a null pointer, for a default label).
4463 The function CONVERTER, when applied to arguments T and V,
4464 converts the value V to the type T.
4466 If not currently inside a case or switch statement, return 1 and do
4467 nothing. The caller will print a language-specific error message.
4468 If VALUE is a duplicate or overlaps, return 2 and do nothing
4469 except store the (first) duplicate node in *DUPLICATE.
4470 If VALUE is out of range, return 3 and do nothing.
4471 If we are jumping into the scope of a cleanup or var-sized array, return 5.
4472 Return 0 on success.
4474 Extended to handle range statements. */
4477 pushcase (value, converter, label, duplicate)
4478 register tree value;
4479 tree (*converter) PROTO((tree, tree));
4480 register tree label;
4483 register struct case_node **l;
4484 register struct case_node *n;
4488 if (output_bytecode)
4489 return bc_pushcase (value, label);
4491 /* Fail if not inside a real case statement. */
4492 if (! (case_stack && case_stack->data.case_stmt.start))
4495 if (stack_block_stack
4496 && stack_block_stack->depth > case_stack->depth)
4499 index_type = TREE_TYPE (case_stack->data.case_stmt.index_expr);
4500 nominal_type = case_stack->data.case_stmt.nominal_type;
4502 /* If the index is erroneous, avoid more problems: pretend to succeed. */
4503 if (index_type == error_mark_node)
4506 /* Convert VALUE to the type in which the comparisons are nominally done. */
4508 value = (*converter) (nominal_type, value);
4510 /* If this is the first label, warn if any insns have been emitted. */
4511 if (case_stack->data.case_stmt.seenlabel == 0)
4514 for (insn = case_stack->data.case_stmt.start;
4516 insn = NEXT_INSN (insn))
4518 if (GET_CODE (insn) == CODE_LABEL)
4520 if (GET_CODE (insn) != NOTE
4521 && (GET_CODE (insn) != INSN || GET_CODE (PATTERN (insn)) != USE))
4523 warning ("unreachable code at beginning of %s",
4524 case_stack->data.case_stmt.printname);
4529 case_stack->data.case_stmt.seenlabel = 1;
4531 /* Fail if this value is out of range for the actual type of the index
4532 (which may be narrower than NOMINAL_TYPE). */
4533 if (value != 0 && ! int_fits_type_p (value, index_type))
4536 /* Fail if this is a duplicate or overlaps another entry. */
4539 if (case_stack->data.case_stmt.default_label != 0)
4541 *duplicate = case_stack->data.case_stmt.default_label;
4544 case_stack->data.case_stmt.default_label = label;
4547 return add_case_node (value, value, label, duplicate);
4549 expand_label (label);
4553 /* Like pushcase but this case applies to all values between VALUE1 and
4554 VALUE2 (inclusive). If VALUE1 is NULL, the range starts at the lowest
4555 value of the index type and ends at VALUE2. If VALUE2 is NULL, the range
4556 starts at VALUE1 and ends at the highest value of the index type.
4557 If both are NULL, this case applies to all values.
4559 The return value is the same as that of pushcase but there is one
4560 additional error code: 4 means the specified range was empty. */
4563 pushcase_range (value1, value2, converter, label, duplicate)
4564 register tree value1, value2;
4565 tree (*converter) PROTO((tree, tree));
4566 register tree label;
4569 register struct case_node **l;
4570 register struct case_node *n;
4574 /* Fail if not inside a real case statement. */
4575 if (! (case_stack && case_stack->data.case_stmt.start))
4578 if (stack_block_stack
4579 && stack_block_stack->depth > case_stack->depth)
4582 index_type = TREE_TYPE (case_stack->data.case_stmt.index_expr);
4583 nominal_type = case_stack->data.case_stmt.nominal_type;
4585 /* If the index is erroneous, avoid more problems: pretend to succeed. */
4586 if (index_type == error_mark_node)
4589 /* If this is the first label, warn if any insns have been emitted. */
4590 if (case_stack->data.case_stmt.seenlabel == 0)
4593 for (insn = case_stack->data.case_stmt.start;
4595 insn = NEXT_INSN (insn))
4597 if (GET_CODE (insn) == CODE_LABEL)
4599 if (GET_CODE (insn) != NOTE
4600 && (GET_CODE (insn) != INSN || GET_CODE (PATTERN (insn)) != USE))
4602 warning ("unreachable code at beginning of %s",
4603 case_stack->data.case_stmt.printname);
4608 case_stack->data.case_stmt.seenlabel = 1;
4610 /* Convert VALUEs to type in which the comparisons are nominally done
4611 and replace any unspecified value with the corresponding bound. */
4613 value1 = TYPE_MIN_VALUE (index_type);
4615 value2 = TYPE_MAX_VALUE (index_type);
4617 /* Fail if the range is empty. Do this before any conversion since
4618 we want to allow out-of-range empty ranges. */
4619 if (tree_int_cst_lt (value2, value1))
4622 value1 = (*converter) (nominal_type, value1);
4623 value2 = (*converter) (nominal_type, value2);
4625 /* Fail if these values are out of range. */
4626 if (TREE_CONSTANT_OVERFLOW (value1)
4627 || ! int_fits_type_p (value1, index_type))
4630 if (TREE_CONSTANT_OVERFLOW (value2)
4631 || ! int_fits_type_p (value2, index_type))
4634 return add_case_node (value1, value2, label, duplicate);
4637 /* Do the actual insertion of a case label for pushcase and pushcase_range
4638 into case_stack->data.case_stmt.case_list. Use an AVL tree to avoid
4639 slowdown for large switch statements. */
4642 add_case_node (low, high, label, duplicate)
4647 struct case_node *p, **q, *r;
4649 q = &case_stack->data.case_stmt.case_list;
4656 /* Keep going past elements distinctly greater than HIGH. */
4657 if (tree_int_cst_lt (high, p->low))
4660 /* or distinctly less than LOW. */
4661 else if (tree_int_cst_lt (p->high, low))
4666 /* We have an overlap; this is an error. */
4667 *duplicate = p->code_label;
4672 /* Add this label to the chain, and succeed.
4673 Copy LOW, HIGH so they are on temporary rather than momentary
4674 obstack and will thus survive till the end of the case statement. */
4676 r = (struct case_node *) oballoc (sizeof (struct case_node));
4677 r->low = copy_node (low);
4679 /* If the bounds are equal, turn this into the one-value case. */
4681 if (tree_int_cst_equal (low, high))
4685 r->high = copy_node (high);
4686 case_stack->data.case_stmt.num_ranges++;
4689 r->code_label = label;
4690 expand_label (label);
4700 struct case_node *s;
4706 if (! (b = p->balance))
4707 /* Growth propagation from left side. */
4714 if (p->left = s = r->right)
4731 case_stack->data.case_stmt.case_list = r;
4734 /* r->balance == +1 */
4739 struct case_node *t = r->right;
4741 if (p->left = s = t->right)
4745 if (r->right = s = t->left)
4767 case_stack->data.case_stmt.case_list = t;
4774 /* p->balance == +1; growth of left side balances the node. */
4784 if (! (b = p->balance))
4785 /* Growth propagation from right side. */
4793 if (p->right = s = r->left)
4810 case_stack->data.case_stmt.case_list = r;
4814 /* r->balance == -1 */
4818 struct case_node *t = r->left;
4820 if (p->right = s = t->left)
4825 if (r->left = s = t->right)
4848 case_stack->data.case_stmt.case_list = t;
4854 /* p->balance == -1; growth of right side balances the node. */
4867 /* Accumulate one case or default label; VALUE is the value of the
4868 case, or nil for a default label. If not currently inside a case,
4869 return 1 and do nothing. If VALUE is a duplicate or overlaps, return
4870 2 and do nothing. If VALUE is out of range, return 3 and do nothing.
4871 Return 0 on success. This function is a leftover from the earlier
4872 bytecode compiler, which was based on gcc 1.37. It should be
4873 merged into pushcase. */
4876 bc_pushcase (value, label)
4880 struct nesting *thiscase = case_stack;
4881 struct case_node *case_label, *new_label;
4886 /* Fail if duplicate, overlap, or out of type range. */
4889 value = convert (thiscase->data.case_stmt.nominal_type, value);
4890 if (! int_fits_type_p (value, thiscase->data.case_stmt.nominal_type))
4893 for (case_label = thiscase->data.case_stmt.case_list;
4894 case_label->left; case_label = case_label->left)
4895 if (! tree_int_cst_lt (case_label->left->high, value))
4898 if (case_label != thiscase->data.case_stmt.case_list
4899 && ! tree_int_cst_lt (case_label->high, value)
4900 || (case_label->left && ! tree_int_cst_lt (value, case_label->left->low)))
4903 new_label = (struct case_node *) oballoc (sizeof (struct case_node));
4904 new_label->low = new_label->high = copy_node (value);
4905 new_label->code_label = label;
4906 new_label->left = case_label->left;
4908 case_label->left = new_label;
4909 thiscase->data.case_stmt.num_ranges++;
4913 if (thiscase->data.case_stmt.default_label)
4915 thiscase->data.case_stmt.default_label = label;
4918 expand_label (label);
4922 /* Returns the number of possible values of TYPE.
4923 Returns -1 if the number is unknown or variable.
4924 Returns -2 if the number does not fit in a HOST_WIDE_INT.
4925 Sets *SPARENESS to 2 if TYPE is an ENUMERAL_TYPE whose values
4926 do not increase monotonically (there may be duplicates);
4927 to 1 if the values increase monotonically, but not always by 1;
4928 otherwise sets it to 0. */
4931 all_cases_count (type, spareness)
4935 HOST_WIDE_INT count, count_high = 0;
4938 switch (TREE_CODE (type))
4945 count = 1 << BITS_PER_UNIT;
4949 if (TREE_CODE (TYPE_MIN_VALUE (type)) != INTEGER_CST
4950 || TREE_CODE (TYPE_MAX_VALUE (type)) != INTEGER_CST)
4955 = TREE_INT_CST_LOW (TYPE_MAX_VALUE (type))
4956 - TREE_INT_CST_LOW (TYPE_MIN_VALUE (type)) + 1
4957 but with overflow checking. */
4958 tree mint = TYPE_MIN_VALUE (type);
4959 tree maxt = TYPE_MAX_VALUE (type);
4960 HOST_WIDE_INT lo, hi;
4961 neg_double(TREE_INT_CST_LOW (mint), TREE_INT_CST_HIGH (mint),
4963 add_double(TREE_INT_CST_LOW (maxt), TREE_INT_CST_HIGH (maxt),
4965 add_double (lo, hi, 1, 0, &lo, &hi);
4966 if (hi != 0 || lo < 0)
4973 for (t = TYPE_VALUES (type); t != NULL_TREE; t = TREE_CHAIN (t))
4975 if (TREE_CODE (TYPE_MIN_VALUE (type)) != INTEGER_CST
4976 || TREE_CODE (TREE_VALUE (t)) != INTEGER_CST
4977 || TREE_INT_CST_LOW (TYPE_MIN_VALUE (type)) + count
4978 != TREE_INT_CST_LOW (TREE_VALUE (t)))
4982 if (*spareness == 1)
4984 tree prev = TREE_VALUE (TYPE_VALUES (type));
4985 for (t = TYPE_VALUES (type); t = TREE_CHAIN (t), t != NULL_TREE; )
4987 if (! tree_int_cst_lt (prev, TREE_VALUE (t)))
4992 prev = TREE_VALUE (t);
5001 #define BITARRAY_TEST(ARRAY, INDEX) \
5002 ((ARRAY)[(unsigned) (INDEX) / HOST_BITS_PER_CHAR]\
5003 & (1 << ((unsigned) (INDEX) % HOST_BITS_PER_CHAR)))
5004 #define BITARRAY_SET(ARRAY, INDEX) \
5005 ((ARRAY)[(unsigned) (INDEX) / HOST_BITS_PER_CHAR]\
5006 |= 1 << ((unsigned) (INDEX) % HOST_BITS_PER_CHAR))
5008 /* Set the elements of the bitstring CASES_SEEN (which has length COUNT),
5009 with the case values we have seen, assuming the case expression
5011 SPARSENESS is as determined by all_cases_count.
5013 The time needed is proportional to COUNT, unless
5014 SPARSENESS is 2, in which case quadratic time is needed. */
5017 mark_seen_cases (type, cases_seen, count, sparseness)
5019 unsigned char *cases_seen;
5025 tree next_node_to_try = NULL_TREE;
5026 long next_node_offset = 0;
5028 register struct case_node *n, *root = case_stack->data.case_stmt.case_list;
5029 tree val = make_node (INTEGER_CST);
5030 TREE_TYPE (val) = type;
5033 else if (sparseness == 2)
5038 /* This less efficient loop is only needed to handle
5039 duplicate case values (multiple enum constants
5040 with the same value). */
5041 TREE_TYPE (val) = TREE_TYPE (root->low);
5042 for (t = TYPE_VALUES (type), xlo = 0; t != NULL_TREE;
5043 t = TREE_CHAIN (t), xlo++)
5045 TREE_INT_CST_LOW (val) = TREE_INT_CST_LOW (TREE_VALUE (t));
5046 TREE_INT_CST_HIGH (val) = TREE_INT_CST_HIGH (TREE_VALUE (t));
5050 /* Keep going past elements distinctly greater than VAL. */
5051 if (tree_int_cst_lt (val, n->low))
5054 /* or distinctly less than VAL. */
5055 else if (tree_int_cst_lt (n->high, val))
5060 /* We have found a matching range. */
5061 BITARRAY_SET (cases_seen, xlo);
5071 case_stack->data.case_stmt.case_list = root = case_tree2list (root, 0);
5072 for (n = root; n; n = n->right)
5074 TREE_INT_CST_LOW (val) = TREE_INT_CST_LOW (n->low);
5075 TREE_INT_CST_HIGH (val) = TREE_INT_CST_HIGH (n->low);
5076 while ( ! tree_int_cst_lt (n->high, val))
5078 /* Calculate (into xlo) the "offset" of the integer (val).
5079 The element with lowest value has offset 0, the next smallest
5080 element has offset 1, etc. */
5082 HOST_WIDE_INT xlo, xhi;
5084 if (sparseness && TYPE_VALUES (type) != NULL_TREE)
5086 /* The TYPE_VALUES will be in increasing order, so
5087 starting searching where we last ended. */
5088 t = next_node_to_try;
5089 xlo = next_node_offset;
5095 t = TYPE_VALUES (type);
5098 if (tree_int_cst_equal (val, TREE_VALUE (t)))
5100 next_node_to_try = TREE_CHAIN (t);
5101 next_node_offset = xlo + 1;
5106 if (t == next_node_to_try)
5115 t = TYPE_MIN_VALUE (type);
5117 neg_double (TREE_INT_CST_LOW (t), TREE_INT_CST_HIGH (t),
5121 add_double (xlo, xhi,
5122 TREE_INT_CST_LOW (val), TREE_INT_CST_HIGH (val),
5126 if (xhi == 0 && xlo >= 0 && xlo < count)
5127 BITARRAY_SET (cases_seen, xlo);
5128 add_double (TREE_INT_CST_LOW (val), TREE_INT_CST_HIGH (val),
5130 &TREE_INT_CST_LOW (val), &TREE_INT_CST_HIGH (val));
5136 /* Called when the index of a switch statement is an enumerated type
5137 and there is no default label.
5139 Checks that all enumeration literals are covered by the case
5140 expressions of a switch. Also, warn if there are any extra
5141 switch cases that are *not* elements of the enumerated type.
5143 If all enumeration literals were covered by the case expressions,
5144 turn one of the expressions into the default expression since it should
5145 not be possible to fall through such a switch. */
5148 check_for_full_enumeration_handling (type)
5151 register struct case_node *n;
5152 register struct case_node **l;
5153 register tree chain;
5156 /* True iff the selector type is a numbered set mode. */
5159 /* The number of possible selector values. */
5162 /* For each possible selector value. a one iff it has been matched
5163 by a case value alternative. */
5164 unsigned char *cases_seen;
5166 /* The allocated size of cases_seen, in chars. */
5170 if (output_bytecode)
5172 bc_check_for_full_enumeration_handling (type);
5179 size = all_cases_count (type, &sparseness);
5180 bytes_needed = (size + HOST_BITS_PER_CHAR) / HOST_BITS_PER_CHAR;
5182 if (size > 0 && size < 600000
5183 /* We deliberately use malloc here - not xmalloc. */
5184 && (cases_seen = (unsigned char *) malloc (bytes_needed)) != NULL)
5187 tree v = TYPE_VALUES (type);
5188 bzero (cases_seen, bytes_needed);
5190 /* The time complexity of this code is normally O(N), where
5191 N being the number of members in the enumerated type.
5192 However, if type is a ENUMERAL_TYPE whose values do not
5193 increase monotonically, O(N*log(N)) time may be needed. */
5195 mark_seen_cases (type, cases_seen, size, sparseness);
5197 for (i = 0; v != NULL_TREE && i < size; i++, v = TREE_CHAIN (v))
5199 if (BITARRAY_TEST(cases_seen, i) == 0)
5200 warning ("enumeration value `%s' not handled in switch",
5201 IDENTIFIER_POINTER (TREE_PURPOSE (v)));
5207 /* Now we go the other way around; we warn if there are case
5208 expressions that don't correspond to enumerators. This can
5209 occur since C and C++ don't enforce type-checking of
5210 assignments to enumeration variables. */
5212 if (case_stack->data.case_stmt.case_list
5213 && case_stack->data.case_stmt.case_list->left)
5214 case_stack->data.case_stmt.case_list
5215 = case_tree2list (case_stack->data.case_stmt.case_list, 0);
5217 for (n = case_stack->data.case_stmt.case_list; n; n = n->right)
5219 for (chain = TYPE_VALUES (type);
5220 chain && !tree_int_cst_equal (n->low, TREE_VALUE (chain));
5221 chain = TREE_CHAIN (chain))
5226 if (TYPE_NAME (type) == 0)
5227 warning ("case value `%d' not in enumerated type",
5228 TREE_INT_CST_LOW (n->low));
5230 warning ("case value `%d' not in enumerated type `%s'",
5231 TREE_INT_CST_LOW (n->low),
5232 IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type))
5235 : DECL_NAME (TYPE_NAME (type))));
5237 if (!tree_int_cst_equal (n->low, n->high))
5239 for (chain = TYPE_VALUES (type);
5240 chain && !tree_int_cst_equal (n->high, TREE_VALUE (chain));
5241 chain = TREE_CHAIN (chain))
5246 if (TYPE_NAME (type) == 0)
5247 warning ("case value `%d' not in enumerated type",
5248 TREE_INT_CST_LOW (n->high));
5250 warning ("case value `%d' not in enumerated type `%s'",
5251 TREE_INT_CST_LOW (n->high),
5252 IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type))
5255 : DECL_NAME (TYPE_NAME (type))));
5261 /* ??? This optimization is disabled because it causes valid programs to
5262 fail. ANSI C does not guarantee that an expression with enum type
5263 will have a value that is the same as one of the enumeration literals. */
5265 /* If all values were found as case labels, make one of them the default
5266 label. Thus, this switch will never fall through. We arbitrarily pick
5267 the last one to make the default since this is likely the most
5268 efficient choice. */
5272 for (l = &case_stack->data.case_stmt.case_list;
5277 case_stack->data.case_stmt.default_label = (*l)->code_label;
5284 /* Check that all enumeration literals are covered by the case
5285 expressions of a switch. Also warn if there are any cases
5286 that are not elements of the enumerated type. */
5289 bc_check_for_full_enumeration_handling (type)
5292 struct nesting *thiscase = case_stack;
5293 struct case_node *c;
5296 /* Check for enums not handled. */
5297 for (e = TYPE_VALUES (type); e; e = TREE_CHAIN (e))
5299 for (c = thiscase->data.case_stmt.case_list->left;
5300 c && tree_int_cst_lt (c->high, TREE_VALUE (e));
5303 if (! (c && tree_int_cst_equal (c->low, TREE_VALUE (e))))
5304 warning ("enumerated value `%s' not handled in switch",
5305 IDENTIFIER_POINTER (TREE_PURPOSE (e)));
5308 /* Check for cases not in the enumeration. */
5309 for (c = thiscase->data.case_stmt.case_list->left; c; c = c->left)
5311 for (e = TYPE_VALUES (type);
5312 e && !tree_int_cst_equal (c->low, TREE_VALUE (e));
5316 warning ("case value `%d' not in enumerated type `%s'",
5317 TREE_INT_CST_LOW (c->low),
5318 IDENTIFIER_POINTER (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE
5320 : DECL_NAME (TYPE_NAME (type))));
5324 /* Terminate a case (Pascal) or switch (C) statement
5325 in which ORIG_INDEX is the expression to be tested.
5326 Generate the code to test it and jump to the right place. */
5329 expand_end_case (orig_index)
5332 tree minval, maxval, range, orig_minval;
5333 rtx default_label = 0;
5334 register struct case_node *n;
5342 register struct nesting *thiscase = case_stack;
5343 tree index_expr, index_type;
5346 if (output_bytecode)
5348 bc_expand_end_case (orig_index);
5352 table_label = gen_label_rtx ();
5353 index_expr = thiscase->data.case_stmt.index_expr;
5354 index_type = TREE_TYPE (index_expr);
5355 unsignedp = TREE_UNSIGNED (index_type);
5357 do_pending_stack_adjust ();
5359 /* An ERROR_MARK occurs for various reasons including invalid data type. */
5360 if (index_type != error_mark_node)
5362 /* If switch expression was an enumerated type, check that all
5363 enumeration literals are covered by the cases.
5364 No sense trying this if there's a default case, however. */
5366 if (!thiscase->data.case_stmt.default_label
5367 && TREE_CODE (TREE_TYPE (orig_index)) == ENUMERAL_TYPE
5368 && TREE_CODE (index_expr) != INTEGER_CST)
5369 check_for_full_enumeration_handling (TREE_TYPE (orig_index));
5371 /* If this is the first label, warn if any insns have been emitted. */
5372 if (thiscase->data.case_stmt.seenlabel == 0)
5375 for (insn = get_last_insn ();
5376 insn != case_stack->data.case_stmt.start;
5377 insn = PREV_INSN (insn))
5378 if (GET_CODE (insn) != NOTE
5379 && (GET_CODE (insn) != INSN || GET_CODE (PATTERN (insn))!= USE))
5381 warning ("unreachable code at beginning of %s",
5382 case_stack->data.case_stmt.printname);
5387 /* If we don't have a default-label, create one here,
5388 after the body of the switch. */
5389 if (thiscase->data.case_stmt.default_label == 0)
5391 thiscase->data.case_stmt.default_label
5392 = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
5393 expand_label (thiscase->data.case_stmt.default_label);
5395 default_label = label_rtx (thiscase->data.case_stmt.default_label);
5397 before_case = get_last_insn ();
5399 if (thiscase->data.case_stmt.case_list
5400 && thiscase->data.case_stmt.case_list->left)
5401 thiscase->data.case_stmt.case_list
5402 = case_tree2list(thiscase->data.case_stmt.case_list, 0);
5404 /* Simplify the case-list before we count it. */
5405 group_case_nodes (thiscase->data.case_stmt.case_list);
5407 /* Get upper and lower bounds of case values.
5408 Also convert all the case values to the index expr's data type. */
5411 for (n = thiscase->data.case_stmt.case_list; n; n = n->right)
5413 /* Check low and high label values are integers. */
5414 if (TREE_CODE (n->low) != INTEGER_CST)
5416 if (TREE_CODE (n->high) != INTEGER_CST)
5419 n->low = convert (index_type, n->low);
5420 n->high = convert (index_type, n->high);
5422 /* Count the elements and track the largest and smallest
5423 of them (treating them as signed even if they are not). */
5431 if (INT_CST_LT (n->low, minval))
5433 if (INT_CST_LT (maxval, n->high))
5436 /* A range counts double, since it requires two compares. */
5437 if (! tree_int_cst_equal (n->low, n->high))
5441 orig_minval = minval;
5443 /* Compute span of values. */
5445 range = fold (build (MINUS_EXPR, index_type, maxval, minval));
5447 end_cleanup_deferral ();
5451 expand_expr (index_expr, const0_rtx, VOIDmode, 0);
5453 emit_jump (default_label);
5456 /* If range of values is much bigger than number of values,
5457 make a sequence of conditional branches instead of a dispatch.
5458 If the switch-index is a constant, do it this way
5459 because we can optimize it. */
5461 #ifndef CASE_VALUES_THRESHOLD
5463 #define CASE_VALUES_THRESHOLD (HAVE_casesi ? 4 : 5)
5465 /* If machine does not have a case insn that compares the
5466 bounds, this means extra overhead for dispatch tables
5467 which raises the threshold for using them. */
5468 #define CASE_VALUES_THRESHOLD 5
5469 #endif /* HAVE_casesi */
5470 #endif /* CASE_VALUES_THRESHOLD */
5472 else if (TREE_INT_CST_HIGH (range) != 0
5473 || count < CASE_VALUES_THRESHOLD
5474 || ((unsigned HOST_WIDE_INT) (TREE_INT_CST_LOW (range))
5476 #ifndef ASM_OUTPUT_ADDR_DIFF_ELT
5479 || TREE_CODE (index_expr) == INTEGER_CST
5480 /* These will reduce to a constant. */
5481 || (TREE_CODE (index_expr) == CALL_EXPR
5482 && TREE_CODE (TREE_OPERAND (index_expr, 0)) == ADDR_EXPR
5483 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (index_expr, 0), 0)) == FUNCTION_DECL
5484 && DECL_FUNCTION_CODE (TREE_OPERAND (TREE_OPERAND (index_expr, 0), 0)) == BUILT_IN_CLASSIFY_TYPE)
5485 || (TREE_CODE (index_expr) == COMPOUND_EXPR
5486 && TREE_CODE (TREE_OPERAND (index_expr, 1)) == INTEGER_CST))
5488 index = expand_expr (index_expr, NULL_RTX, VOIDmode, 0);
5490 /* If the index is a short or char that we do not have
5491 an insn to handle comparisons directly, convert it to
5492 a full integer now, rather than letting each comparison
5493 generate the conversion. */
5495 if (GET_MODE_CLASS (GET_MODE (index)) == MODE_INT
5496 && (cmp_optab->handlers[(int) GET_MODE(index)].insn_code
5497 == CODE_FOR_nothing))
5499 enum machine_mode wider_mode;
5500 for (wider_mode = GET_MODE (index); wider_mode != VOIDmode;
5501 wider_mode = GET_MODE_WIDER_MODE (wider_mode))
5502 if (cmp_optab->handlers[(int) wider_mode].insn_code
5503 != CODE_FOR_nothing)
5505 index = convert_to_mode (wider_mode, index, unsignedp);
5511 do_pending_stack_adjust ();
5513 index = protect_from_queue (index, 0);
5514 if (GET_CODE (index) == MEM)
5515 index = copy_to_reg (index);
5516 if (GET_CODE (index) == CONST_INT
5517 || TREE_CODE (index_expr) == INTEGER_CST)
5519 /* Make a tree node with the proper constant value
5520 if we don't already have one. */
5521 if (TREE_CODE (index_expr) != INTEGER_CST)
5524 = build_int_2 (INTVAL (index),
5525 unsignedp || INTVAL (index) >= 0 ? 0 : -1);
5526 index_expr = convert (index_type, index_expr);
5529 /* For constant index expressions we need only
5530 issue a unconditional branch to the appropriate
5531 target code. The job of removing any unreachable
5532 code is left to the optimisation phase if the
5533 "-O" option is specified. */
5534 for (n = thiscase->data.case_stmt.case_list; n; n = n->right)
5535 if (! tree_int_cst_lt (index_expr, n->low)
5536 && ! tree_int_cst_lt (n->high, index_expr))
5540 emit_jump (label_rtx (n->code_label));
5542 emit_jump (default_label);
5546 /* If the index expression is not constant we generate
5547 a binary decision tree to select the appropriate
5548 target code. This is done as follows:
5550 The list of cases is rearranged into a binary tree,
5551 nearly optimal assuming equal probability for each case.
5553 The tree is transformed into RTL, eliminating
5554 redundant test conditions at the same time.
5556 If program flow could reach the end of the
5557 decision tree an unconditional jump to the
5558 default code is emitted. */
5561 = (TREE_CODE (TREE_TYPE (orig_index)) != ENUMERAL_TYPE
5562 && estimate_case_costs (thiscase->data.case_stmt.case_list));
5563 balance_case_nodes (&thiscase->data.case_stmt.case_list,
5565 emit_case_nodes (index, thiscase->data.case_stmt.case_list,
5566 default_label, index_type);
5567 emit_jump_if_reachable (default_label);
5576 enum machine_mode index_mode = SImode;
5577 int index_bits = GET_MODE_BITSIZE (index_mode);
5579 enum machine_mode op_mode;
5581 /* Convert the index to SImode. */
5582 if (GET_MODE_BITSIZE (TYPE_MODE (index_type))
5583 > GET_MODE_BITSIZE (index_mode))
5585 enum machine_mode omode = TYPE_MODE (index_type);
5586 rtx rangertx = expand_expr (range, NULL_RTX, VOIDmode, 0);
5588 /* We must handle the endpoints in the original mode. */
5589 index_expr = build (MINUS_EXPR, index_type,
5590 index_expr, minval);
5591 minval = integer_zero_node;
5592 index = expand_expr (index_expr, NULL_RTX, VOIDmode, 0);
5593 emit_cmp_insn (rangertx, index, LTU, NULL_RTX, omode, 1, 0);
5594 emit_jump_insn (gen_bltu (default_label));
5595 /* Now we can safely truncate. */
5596 index = convert_to_mode (index_mode, index, 0);
5600 if (TYPE_MODE (index_type) != index_mode)
5602 index_expr = convert (type_for_size (index_bits, 0),
5604 index_type = TREE_TYPE (index_expr);
5607 index = expand_expr (index_expr, NULL_RTX, VOIDmode, 0);
5610 index = protect_from_queue (index, 0);
5611 do_pending_stack_adjust ();
5613 op_mode = insn_operand_mode[(int)CODE_FOR_casesi][0];
5614 if (! (*insn_operand_predicate[(int)CODE_FOR_casesi][0])
5616 index = copy_to_mode_reg (op_mode, index);
5618 op1 = expand_expr (minval, NULL_RTX, VOIDmode, 0);
5620 op_mode = insn_operand_mode[(int)CODE_FOR_casesi][1];
5621 if (! (*insn_operand_predicate[(int)CODE_FOR_casesi][1])
5623 op1 = copy_to_mode_reg (op_mode, op1);
5625 op2 = expand_expr (range, NULL_RTX, VOIDmode, 0);
5627 op_mode = insn_operand_mode[(int)CODE_FOR_casesi][2];
5628 if (! (*insn_operand_predicate[(int)CODE_FOR_casesi][2])
5630 op2 = copy_to_mode_reg (op_mode, op2);
5632 emit_jump_insn (gen_casesi (index, op1, op2,
5633 table_label, default_label));
5637 #ifdef HAVE_tablejump
5638 if (! win && HAVE_tablejump)
5640 index_expr = convert (thiscase->data.case_stmt.nominal_type,
5641 fold (build (MINUS_EXPR, index_type,
5642 index_expr, minval)));
5643 index_type = TREE_TYPE (index_expr);
5644 index = expand_expr (index_expr, NULL_RTX, VOIDmode, 0);
5646 index = protect_from_queue (index, 0);
5647 do_pending_stack_adjust ();
5649 do_tablejump (index, TYPE_MODE (index_type),
5650 expand_expr (range, NULL_RTX, VOIDmode, 0),
5651 table_label, default_label);
5658 /* Get table of labels to jump to, in order of case index. */
5660 ncases = TREE_INT_CST_LOW (range) + 1;
5661 labelvec = (rtx *) alloca (ncases * sizeof (rtx));
5662 bzero ((char *) labelvec, ncases * sizeof (rtx));
5664 for (n = thiscase->data.case_stmt.case_list; n; n = n->right)
5666 register HOST_WIDE_INT i
5667 = TREE_INT_CST_LOW (n->low) - TREE_INT_CST_LOW (orig_minval);
5672 = gen_rtx (LABEL_REF, Pmode, label_rtx (n->code_label));
5673 if (i + TREE_INT_CST_LOW (orig_minval)
5674 == TREE_INT_CST_LOW (n->high))
5680 /* Fill in the gaps with the default. */
5681 for (i = 0; i < ncases; i++)
5682 if (labelvec[i] == 0)
5683 labelvec[i] = gen_rtx (LABEL_REF, Pmode, default_label);
5685 /* Output the table */
5686 emit_label (table_label);
5688 /* This would be a lot nicer if CASE_VECTOR_PC_RELATIVE
5689 were an expression, instead of an #ifdef/#ifndef. */
5691 #ifdef CASE_VECTOR_PC_RELATIVE
5695 emit_jump_insn (gen_rtx (ADDR_DIFF_VEC, CASE_VECTOR_MODE,
5696 gen_rtx (LABEL_REF, Pmode, table_label),
5697 gen_rtvec_v (ncases, labelvec)));
5699 emit_jump_insn (gen_rtx (ADDR_VEC, CASE_VECTOR_MODE,
5700 gen_rtvec_v (ncases, labelvec)));
5702 /* If the case insn drops through the table,
5703 after the table we must jump to the default-label.
5704 Otherwise record no drop-through after the table. */
5705 #ifdef CASE_DROPS_THROUGH
5706 emit_jump (default_label);
5712 before_case = squeeze_notes (NEXT_INSN (before_case), get_last_insn ());
5713 reorder_insns (before_case, get_last_insn (),
5714 thiscase->data.case_stmt.start);
5717 end_cleanup_deferral ();
5719 if (thiscase->exit_label)
5720 emit_label (thiscase->exit_label);
5722 POPSTACK (case_stack);
5727 /* Convert the tree NODE into a list linked by the right field, with the left
5728 field zeroed. RIGHT is used for recursion; it is a list to be placed
5729 rightmost in the resulting list. */
5731 static struct case_node *
5732 case_tree2list (node, right)
5733 struct case_node *node, *right;
5735 struct case_node *left;
5738 right = case_tree2list (node->right, right);
5740 node->right = right;
5741 if (left = node->left)
5744 return case_tree2list (left, node);
5750 /* Terminate a case statement. EXPR is the original index
5754 bc_expand_end_case (expr)
5757 struct nesting *thiscase = case_stack;
5758 enum bytecode_opcode opcode;
5759 struct bc_label *jump_label;
5760 struct case_node *c;
5762 bc_emit_bytecode (jump);
5763 bc_emit_bytecode_labelref (BYTECODE_BC_LABEL (thiscase->exit_label));
5765 #ifdef DEBUG_PRINT_CODE
5766 fputc ('\n', stderr);
5769 /* Now that the size of the jump table is known, emit the actual
5770 indexed jump instruction. */
5771 bc_emit_bytecode_labeldef (BYTECODE_BC_LABEL (thiscase->data.case_stmt.skip_label));
5773 opcode = TYPE_MODE (thiscase->data.case_stmt.nominal_type) == SImode
5774 ? TREE_UNSIGNED (thiscase->data.case_stmt.nominal_type) ? caseSU : caseSI
5775 : TREE_UNSIGNED (thiscase->data.case_stmt.nominal_type) ? caseDU : caseDI;
5777 bc_emit_bytecode (opcode);
5779 /* Now emit the case instructions literal arguments, in order.
5780 In addition to the value on the stack, it uses:
5781 1. The address of the jump table.
5782 2. The size of the jump table.
5783 3. The default label. */
5785 jump_label = bc_get_bytecode_label ();
5786 bc_emit_bytecode_labelref (jump_label);
5787 bc_emit_bytecode_const ((char *) &thiscase->data.case_stmt.num_ranges,
5788 sizeof thiscase->data.case_stmt.num_ranges);
5790 if (thiscase->data.case_stmt.default_label)
5791 bc_emit_bytecode_labelref (BYTECODE_BC_LABEL (DECL_RTL (thiscase->data.case_stmt.default_label)));
5793 bc_emit_bytecode_labelref (BYTECODE_BC_LABEL (thiscase->exit_label));
5795 /* Output the jump table. */
5797 bc_align_bytecode (3 /* PTR_ALIGN */);
5798 bc_emit_bytecode_labeldef (jump_label);
5800 if (TYPE_MODE (thiscase->data.case_stmt.nominal_type) == SImode)
5801 for (c = thiscase->data.case_stmt.case_list->left; c; c = c->left)
5803 opcode = TREE_INT_CST_LOW (c->low);
5804 bc_emit_bytecode_const ((char *) &opcode, sizeof opcode);
5806 opcode = TREE_INT_CST_LOW (c->high);
5807 bc_emit_bytecode_const ((char *) &opcode, sizeof opcode);
5809 bc_emit_bytecode_labelref (BYTECODE_BC_LABEL (DECL_RTL (c->code_label)));
5812 if (TYPE_MODE (thiscase->data.case_stmt.nominal_type) == DImode)
5813 for (c = thiscase->data.case_stmt.case_list->left; c; c = c->left)
5815 bc_emit_bytecode_DI_const (c->low);
5816 bc_emit_bytecode_DI_const (c->high);
5818 bc_emit_bytecode_labelref (BYTECODE_BC_LABEL (DECL_RTL (c->code_label)));
5825 bc_emit_bytecode_labeldef (BYTECODE_BC_LABEL (thiscase->exit_label));
5827 /* Possibly issue enumeration warnings. */
5829 if (!thiscase->data.case_stmt.default_label
5830 && TREE_CODE (TREE_TYPE (expr)) == ENUMERAL_TYPE
5831 && TREE_CODE (expr) != INTEGER_CST
5833 check_for_full_enumeration_handling (TREE_TYPE (expr));
5836 #ifdef DEBUG_PRINT_CODE
5837 fputc ('\n', stderr);
5840 POPSTACK (case_stack);
5844 /* Return unique bytecode ID. */
5849 static int bc_uid = 0;
5854 /* Generate code to jump to LABEL if OP1 and OP2 are equal. */
5857 do_jump_if_equal (op1, op2, label, unsignedp)
5858 rtx op1, op2, label;
5861 if (GET_CODE (op1) == CONST_INT
5862 && GET_CODE (op2) == CONST_INT)
5864 if (INTVAL (op1) == INTVAL (op2))
5869 enum machine_mode mode = GET_MODE (op1);
5870 if (mode == VOIDmode)
5871 mode = GET_MODE (op2);
5872 emit_cmp_insn (op1, op2, EQ, NULL_RTX, mode, unsignedp, 0);
5873 emit_jump_insn (gen_beq (label));
5877 /* Not all case values are encountered equally. This function
5878 uses a heuristic to weight case labels, in cases where that
5879 looks like a reasonable thing to do.
5881 Right now, all we try to guess is text, and we establish the
5884 chars above space: 16
5893 If we find any cases in the switch that are not either -1 or in the range
5894 of valid ASCII characters, or are control characters other than those
5895 commonly used with "\", don't treat this switch scanning text.
5897 Return 1 if these nodes are suitable for cost estimation, otherwise
5901 estimate_case_costs (node)
5904 tree min_ascii = build_int_2 (-1, -1);
5905 tree max_ascii = convert (TREE_TYPE (node->high), build_int_2 (127, 0));
5909 /* If we haven't already made the cost table, make it now. Note that the
5910 lower bound of the table is -1, not zero. */
5912 if (cost_table == NULL)
5914 cost_table = ((short *) xmalloc (129 * sizeof (short))) + 1;
5915 bzero ((char *) (cost_table - 1), 129 * sizeof (short));
5917 for (i = 0; i < 128; i++)
5921 else if (ispunct (i))
5923 else if (iscntrl (i))
5927 cost_table[' '] = 8;
5928 cost_table['\t'] = 4;
5929 cost_table['\0'] = 4;
5930 cost_table['\n'] = 2;
5931 cost_table['\f'] = 1;
5932 cost_table['\v'] = 1;
5933 cost_table['\b'] = 1;
5936 /* See if all the case expressions look like text. It is text if the
5937 constant is >= -1 and the highest constant is <= 127. Do all comparisons
5938 as signed arithmetic since we don't want to ever access cost_table with a
5939 value less than -1. Also check that none of the constants in a range
5940 are strange control characters. */
5942 for (n = node; n; n = n->right)
5944 if ((INT_CST_LT (n->low, min_ascii)) || INT_CST_LT (max_ascii, n->high))
5947 for (i = TREE_INT_CST_LOW (n->low); i <= TREE_INT_CST_LOW (n->high); i++)
5948 if (cost_table[i] < 0)
5952 /* All interesting values are within the range of interesting
5953 ASCII characters. */
5957 /* Scan an ordered list of case nodes
5958 combining those with consecutive values or ranges.
5960 Eg. three separate entries 1: 2: 3: become one entry 1..3: */
5963 group_case_nodes (head)
5966 case_node_ptr node = head;
5970 rtx lb = next_real_insn (label_rtx (node->code_label));
5972 case_node_ptr np = node;
5974 /* Try to group the successors of NODE with NODE. */
5975 while (((np = np->right) != 0)
5976 /* Do they jump to the same place? */
5977 && ((lb2 = next_real_insn (label_rtx (np->code_label))) == lb
5978 || (lb != 0 && lb2 != 0
5979 && simplejump_p (lb)
5980 && simplejump_p (lb2)
5981 && rtx_equal_p (SET_SRC (PATTERN (lb)),
5982 SET_SRC (PATTERN (lb2)))))
5983 /* Are their ranges consecutive? */
5984 && tree_int_cst_equal (np->low,
5985 fold (build (PLUS_EXPR,
5986 TREE_TYPE (node->high),
5989 /* An overflow is not consecutive. */
5990 && tree_int_cst_lt (node->high,
5991 fold (build (PLUS_EXPR,
5992 TREE_TYPE (node->high),
5994 integer_one_node))))
5996 node->high = np->high;
5998 /* NP is the first node after NODE which can't be grouped with it.
5999 Delete the nodes in between, and move on to that node. */
6005 /* Take an ordered list of case nodes
6006 and transform them into a near optimal binary tree,
6007 on the assumption that any target code selection value is as
6008 likely as any other.
6010 The transformation is performed by splitting the ordered
6011 list into two equal sections plus a pivot. The parts are
6012 then attached to the pivot as left and right branches. Each
6013 branch is is then transformed recursively. */
6016 balance_case_nodes (head, parent)
6017 case_node_ptr *head;
6018 case_node_ptr parent;
6020 register case_node_ptr np;
6028 register case_node_ptr *npp;
6031 /* Count the number of entries on branch. Also count the ranges. */
6035 if (!tree_int_cst_equal (np->low, np->high))
6039 cost += cost_table[TREE_INT_CST_LOW (np->high)];
6043 cost += cost_table[TREE_INT_CST_LOW (np->low)];
6051 /* Split this list if it is long enough for that to help. */
6056 /* Find the place in the list that bisects the list's total cost,
6057 Here I gets half the total cost. */
6062 /* Skip nodes while their cost does not reach that amount. */
6063 if (!tree_int_cst_equal ((*npp)->low, (*npp)->high))
6064 i -= cost_table[TREE_INT_CST_LOW ((*npp)->high)];
6065 i -= cost_table[TREE_INT_CST_LOW ((*npp)->low)];
6068 npp = &(*npp)->right;
6073 /* Leave this branch lopsided, but optimize left-hand
6074 side and fill in `parent' fields for right-hand side. */
6076 np->parent = parent;
6077 balance_case_nodes (&np->left, np);
6078 for (; np->right; np = np->right)
6079 np->right->parent = np;
6083 /* If there are just three nodes, split at the middle one. */
6085 npp = &(*npp)->right;
6088 /* Find the place in the list that bisects the list's total cost,
6089 where ranges count as 2.
6090 Here I gets half the total cost. */
6091 i = (i + ranges + 1) / 2;
6094 /* Skip nodes while their cost does not reach that amount. */
6095 if (!tree_int_cst_equal ((*npp)->low, (*npp)->high))
6100 npp = &(*npp)->right;
6105 np->parent = parent;
6108 /* Optimize each of the two split parts. */
6109 balance_case_nodes (&np->left, np);
6110 balance_case_nodes (&np->right, np);
6114 /* Else leave this branch as one level,
6115 but fill in `parent' fields. */
6117 np->parent = parent;
6118 for (; np->right; np = np->right)
6119 np->right->parent = np;
6124 /* Search the parent sections of the case node tree
6125 to see if a test for the lower bound of NODE would be redundant.
6126 INDEX_TYPE is the type of the index expression.
6128 The instructions to generate the case decision tree are
6129 output in the same order as nodes are processed so it is
6130 known that if a parent node checks the range of the current
6131 node minus one that the current node is bounded at its lower
6132 span. Thus the test would be redundant. */
6135 node_has_low_bound (node, index_type)
6140 case_node_ptr pnode;
6142 /* If the lower bound of this node is the lowest value in the index type,
6143 we need not test it. */
6145 if (tree_int_cst_equal (node->low, TYPE_MIN_VALUE (index_type)))
6148 /* If this node has a left branch, the value at the left must be less
6149 than that at this node, so it cannot be bounded at the bottom and
6150 we need not bother testing any further. */
6155 low_minus_one = fold (build (MINUS_EXPR, TREE_TYPE (node->low),
6156 node->low, integer_one_node));
6158 /* If the subtraction above overflowed, we can't verify anything.
6159 Otherwise, look for a parent that tests our value - 1. */
6161 if (! tree_int_cst_lt (low_minus_one, node->low))
6164 for (pnode = node->parent; pnode; pnode = pnode->parent)
6165 if (tree_int_cst_equal (low_minus_one, pnode->high))
6171 /* Search the parent sections of the case node tree
6172 to see if a test for the upper bound of NODE would be redundant.
6173 INDEX_TYPE is the type of the index expression.
6175 The instructions to generate the case decision tree are
6176 output in the same order as nodes are processed so it is
6177 known that if a parent node checks the range of the current
6178 node plus one that the current node is bounded at its upper
6179 span. Thus the test would be redundant. */
6182 node_has_high_bound (node, index_type)
6187 case_node_ptr pnode;
6189 /* If the upper bound of this node is the highest value in the type
6190 of the index expression, we need not test against it. */
6192 if (tree_int_cst_equal (node->high, TYPE_MAX_VALUE (index_type)))
6195 /* If this node has a right branch, the value at the right must be greater
6196 than that at this node, so it cannot be bounded at the top and
6197 we need not bother testing any further. */
6202 high_plus_one = fold (build (PLUS_EXPR, TREE_TYPE (node->high),
6203 node->high, integer_one_node));
6205 /* If the addition above overflowed, we can't verify anything.
6206 Otherwise, look for a parent that tests our value + 1. */
6208 if (! tree_int_cst_lt (node->high, high_plus_one))
6211 for (pnode = node->parent; pnode; pnode = pnode->parent)
6212 if (tree_int_cst_equal (high_plus_one, pnode->low))
6218 /* Search the parent sections of the
6219 case node tree to see if both tests for the upper and lower
6220 bounds of NODE would be redundant. */
6223 node_is_bounded (node, index_type)
6227 return (node_has_low_bound (node, index_type)
6228 && node_has_high_bound (node, index_type));
6231 /* Emit an unconditional jump to LABEL unless it would be dead code. */
6234 emit_jump_if_reachable (label)
6237 if (GET_CODE (get_last_insn ()) != BARRIER)
6241 /* Emit step-by-step code to select a case for the value of INDEX.
6242 The thus generated decision tree follows the form of the
6243 case-node binary tree NODE, whose nodes represent test conditions.
6244 INDEX_TYPE is the type of the index of the switch.
6246 Care is taken to prune redundant tests from the decision tree
6247 by detecting any boundary conditions already checked by
6248 emitted rtx. (See node_has_high_bound, node_has_low_bound
6249 and node_is_bounded, above.)
6251 Where the test conditions can be shown to be redundant we emit
6252 an unconditional jump to the target code. As a further
6253 optimization, the subordinates of a tree node are examined to
6254 check for bounded nodes. In this case conditional and/or
6255 unconditional jumps as a result of the boundary check for the
6256 current node are arranged to target the subordinates associated
6257 code for out of bound conditions on the current node node.
6259 We can assume that when control reaches the code generated here,
6260 the index value has already been compared with the parents
6261 of this node, and determined to be on the same side of each parent
6262 as this node is. Thus, if this node tests for the value 51,
6263 and a parent tested for 52, we don't need to consider
6264 the possibility of a value greater than 51. If another parent
6265 tests for the value 50, then this node need not test anything. */
6268 emit_case_nodes (index, node, default_label, index_type)
6274 /* If INDEX has an unsigned type, we must make unsigned branches. */
6275 int unsignedp = TREE_UNSIGNED (index_type);
6276 typedef rtx rtx_function ();
6277 rtx_function *gen_bgt_pat = unsignedp ? gen_bgtu : gen_bgt;
6278 rtx_function *gen_bge_pat = unsignedp ? gen_bgeu : gen_bge;
6279 rtx_function *gen_blt_pat = unsignedp ? gen_bltu : gen_blt;
6280 rtx_function *gen_ble_pat = unsignedp ? gen_bleu : gen_ble;
6281 enum machine_mode mode = GET_MODE (index);
6283 /* See if our parents have already tested everything for us.
6284 If they have, emit an unconditional jump for this node. */
6285 if (node_is_bounded (node, index_type))
6286 emit_jump (label_rtx (node->code_label));
6288 else if (tree_int_cst_equal (node->low, node->high))
6290 /* Node is single valued. First see if the index expression matches
6291 this node and then check our children, if any. */
6293 do_jump_if_equal (index, expand_expr (node->low, NULL_RTX, VOIDmode, 0),
6294 label_rtx (node->code_label), unsignedp);
6296 if (node->right != 0 && node->left != 0)
6298 /* This node has children on both sides.
6299 Dispatch to one side or the other
6300 by comparing the index value with this node's value.
6301 If one subtree is bounded, check that one first,
6302 so we can avoid real branches in the tree. */
6304 if (node_is_bounded (node->right, index_type))
6306 emit_cmp_insn (index, expand_expr (node->high, NULL_RTX,
6308 GT, NULL_RTX, mode, unsignedp, 0);
6310 emit_jump_insn ((*gen_bgt_pat) (label_rtx (node->right->code_label)));
6311 emit_case_nodes (index, node->left, default_label, index_type);
6314 else if (node_is_bounded (node->left, index_type))
6316 emit_cmp_insn (index, expand_expr (node->high, NULL_RTX,
6318 LT, NULL_RTX, mode, unsignedp, 0);
6319 emit_jump_insn ((*gen_blt_pat) (label_rtx (node->left->code_label)));
6320 emit_case_nodes (index, node->right, default_label, index_type);
6325 /* Neither node is bounded. First distinguish the two sides;
6326 then emit the code for one side at a time. */
6329 = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
6331 /* See if the value is on the right. */
6332 emit_cmp_insn (index, expand_expr (node->high, NULL_RTX,
6334 GT, NULL_RTX, mode, unsignedp, 0);
6335 emit_jump_insn ((*gen_bgt_pat) (label_rtx (test_label)));
6337 /* Value must be on the left.
6338 Handle the left-hand subtree. */
6339 emit_case_nodes (index, node->left, default_label, index_type);
6340 /* If left-hand subtree does nothing,
6342 emit_jump_if_reachable (default_label);
6344 /* Code branches here for the right-hand subtree. */
6345 expand_label (test_label);
6346 emit_case_nodes (index, node->right, default_label, index_type);
6350 else if (node->right != 0 && node->left == 0)
6352 /* Here we have a right child but no left so we issue conditional
6353 branch to default and process the right child.
6355 Omit the conditional branch to default if we it avoid only one
6356 right child; it costs too much space to save so little time. */
6358 if (node->right->right || node->right->left
6359 || !tree_int_cst_equal (node->right->low, node->right->high))
6361 if (!node_has_low_bound (node, index_type))
6363 emit_cmp_insn (index, expand_expr (node->high, NULL_RTX,
6365 LT, NULL_RTX, mode, unsignedp, 0);
6366 emit_jump_insn ((*gen_blt_pat) (default_label));
6369 emit_case_nodes (index, node->right, default_label, index_type);
6372 /* We cannot process node->right normally
6373 since we haven't ruled out the numbers less than
6374 this node's value. So handle node->right explicitly. */
6375 do_jump_if_equal (index,
6376 expand_expr (node->right->low, NULL_RTX,
6378 label_rtx (node->right->code_label), unsignedp);
6381 else if (node->right == 0 && node->left != 0)
6383 /* Just one subtree, on the left. */
6385 #if 0 /* The following code and comment were formerly part
6386 of the condition here, but they didn't work
6387 and I don't understand what the idea was. -- rms. */
6388 /* If our "most probable entry" is less probable
6389 than the default label, emit a jump to
6390 the default label using condition codes
6391 already lying around. With no right branch,
6392 a branch-greater-than will get us to the default
6395 && cost_table[TREE_INT_CST_LOW (node->high)] < 12)
6398 if (node->left->left || node->left->right
6399 || !tree_int_cst_equal (node->left->low, node->left->high))
6401 if (!node_has_high_bound (node, index_type))
6403 emit_cmp_insn (index, expand_expr (node->high, NULL_RTX,
6405 GT, NULL_RTX, mode, unsignedp, 0);
6406 emit_jump_insn ((*gen_bgt_pat) (default_label));
6409 emit_case_nodes (index, node->left, default_label, index_type);
6412 /* We cannot process node->left normally
6413 since we haven't ruled out the numbers less than
6414 this node's value. So handle node->left explicitly. */
6415 do_jump_if_equal (index,
6416 expand_expr (node->left->low, NULL_RTX,
6418 label_rtx (node->left->code_label), unsignedp);
6423 /* Node is a range. These cases are very similar to those for a single
6424 value, except that we do not start by testing whether this node
6425 is the one to branch to. */
6427 if (node->right != 0 && node->left != 0)
6429 /* Node has subtrees on both sides.
6430 If the right-hand subtree is bounded,
6431 test for it first, since we can go straight there.
6432 Otherwise, we need to make a branch in the control structure,
6433 then handle the two subtrees. */
6434 tree test_label = 0;
6436 emit_cmp_insn (index, expand_expr (node->high, NULL_RTX,
6438 GT, NULL_RTX, mode, unsignedp, 0);
6440 if (node_is_bounded (node->right, index_type))
6441 /* Right hand node is fully bounded so we can eliminate any
6442 testing and branch directly to the target code. */
6443 emit_jump_insn ((*gen_bgt_pat) (label_rtx (node->right->code_label)));
6446 /* Right hand node requires testing.
6447 Branch to a label where we will handle it later. */
6449 test_label = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
6450 emit_jump_insn ((*gen_bgt_pat) (label_rtx (test_label)));
6453 /* Value belongs to this node or to the left-hand subtree. */
6455 emit_cmp_insn (index, expand_expr (node->low, NULL_RTX, VOIDmode, 0),
6456 GE, NULL_RTX, mode, unsignedp, 0);
6457 emit_jump_insn ((*gen_bge_pat) (label_rtx (node->code_label)));
6459 /* Handle the left-hand subtree. */
6460 emit_case_nodes (index, node->left, default_label, index_type);
6462 /* If right node had to be handled later, do that now. */
6466 /* If the left-hand subtree fell through,
6467 don't let it fall into the right-hand subtree. */
6468 emit_jump_if_reachable (default_label);
6470 expand_label (test_label);
6471 emit_case_nodes (index, node->right, default_label, index_type);
6475 else if (node->right != 0 && node->left == 0)
6477 /* Deal with values to the left of this node,
6478 if they are possible. */
6479 if (!node_has_low_bound (node, index_type))
6481 emit_cmp_insn (index, expand_expr (node->low, NULL_RTX,
6483 LT, NULL_RTX, mode, unsignedp, 0);
6484 emit_jump_insn ((*gen_blt_pat) (default_label));
6487 /* Value belongs to this node or to the right-hand subtree. */
6489 emit_cmp_insn (index, expand_expr (node->high, NULL_RTX,
6491 LE, NULL_RTX, mode, unsignedp, 0);
6492 emit_jump_insn ((*gen_ble_pat) (label_rtx (node->code_label)));
6494 emit_case_nodes (index, node->right, default_label, index_type);
6497 else if (node->right == 0 && node->left != 0)
6499 /* Deal with values to the right of this node,
6500 if they are possible. */
6501 if (!node_has_high_bound (node, index_type))
6503 emit_cmp_insn (index, expand_expr (node->high, NULL_RTX,
6505 GT, NULL_RTX, mode, unsignedp, 0);
6506 emit_jump_insn ((*gen_bgt_pat) (default_label));
6509 /* Value belongs to this node or to the left-hand subtree. */
6511 emit_cmp_insn (index, expand_expr (node->low, NULL_RTX, VOIDmode, 0),
6512 GE, NULL_RTX, mode, unsignedp, 0);
6513 emit_jump_insn ((*gen_bge_pat) (label_rtx (node->code_label)));
6515 emit_case_nodes (index, node->left, default_label, index_type);
6520 /* Node has no children so we check low and high bounds to remove
6521 redundant tests. Only one of the bounds can exist,
6522 since otherwise this node is bounded--a case tested already. */
6524 if (!node_has_high_bound (node, index_type))
6526 emit_cmp_insn (index, expand_expr (node->high, NULL_RTX,
6528 GT, NULL_RTX, mode, unsignedp, 0);
6529 emit_jump_insn ((*gen_bgt_pat) (default_label));
6532 if (!node_has_low_bound (node, index_type))
6534 emit_cmp_insn (index, expand_expr (node->low, NULL_RTX,
6536 LT, NULL_RTX, mode, unsignedp, 0);
6537 emit_jump_insn ((*gen_blt_pat) (default_label));
6540 emit_jump (label_rtx (node->code_label));
6545 /* These routines are used by the loop unrolling code. They copy BLOCK trees
6546 so that the debugging info will be correct for the unrolled loop. */
6548 /* Indexed by block number, contains a pointer to the N'th block node. */
6550 static tree *block_vector;
6553 find_loop_tree_blocks ()
6555 tree block = DECL_INITIAL (current_function_decl);
6557 block_vector = identify_blocks (block, get_insns ());
6561 unroll_block_trees ()
6563 tree block = DECL_INITIAL (current_function_decl);
6565 reorder_blocks (block_vector, block, get_insns ());