1 /* This file contains the definitions and documentation for the common
2 tree codes used in the GNU C and C++ compilers (see c-common.def
3 for the standard codes).
4 Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
5 Written by Benjamin Chelf (chelf@codesourcery.com).
6
7 This file is part of GCC.
8
9 GCC is free software; you can redistribute it and/or modify it under
10 the terms of the GNU General Public License as published by the Free
11 Software Foundation; either version 2, or (at your option) any later
12 version.
13
14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to the Free
21 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 02111-1307, USA. */
23
24 #include "config.h"
25 #include "system.h"
26 #include "tree.h"
27 #include "function.h"
28 #include "splay-tree.h"
29 #include "varray.h"
30 #include "c-common.h"
31 #include "except.h"
32 #include "toplev.h"
33 #include "flags.h"
34 #include "ggc.h"
35 #include "rtl.h"
36 #include "expr.h"
37 #include "output.h"
38 #include "timevar.h"
39 #include "predict.h"
40
41 /* If non-NULL, the address of a language-specific function for
42 expanding statements. */
43 void (*lang_expand_stmt) PARAMS ((tree));
44
45 /* If non-NULL, the address of a language-specific function for
46 expanding a DECL_STMT. After the language-independent cases are
47 handled, this function will be called. If this function is not
48 defined, it is assumed that declarations other than those for
49 variables and labels do not require any RTL generation. */
50 void (*lang_expand_decl_stmt) PARAMS ((tree));
51
52 /* Create an empty statement tree rooted at T. */
53
54 void
begin_stmt_tree(t)55 begin_stmt_tree (t)
56 tree *t;
57 {
58 /* We create a trivial EXPR_STMT so that last_tree is never NULL in
59 what follows. We remove the extraneous statement in
60 finish_stmt_tree. */
61 *t = build_nt (EXPR_STMT, void_zero_node);
62 last_tree = *t;
63 last_expr_type = NULL_TREE;
64 last_expr_filename = input_filename;
65 }
66
67 /* T is a statement. Add it to the statement-tree. */
68
69 tree
add_stmt(t)70 add_stmt (t)
71 tree t;
72 {
73 if (input_filename != last_expr_filename)
74 {
75 /* If the filename has changed, also add in a FILE_STMT. Do a string
76 compare first, though, as it might be an equivalent string. */
77 int add = (strcmp (input_filename, last_expr_filename) != 0);
78 last_expr_filename = input_filename;
79 if (add)
80 {
81 tree pos = build_nt (FILE_STMT, get_identifier (input_filename));
82 add_stmt (pos);
83 }
84 }
85
86 /* Add T to the statement-tree. */
87 TREE_CHAIN (last_tree) = t;
88 last_tree = t;
89
90 /* When we expand a statement-tree, we must know whether or not the
91 statements are full-expressions. We record that fact here. */
92 STMT_IS_FULL_EXPR_P (last_tree) = stmts_are_full_exprs_p ();
93
94 /* Keep track of the number of statements in this function. */
95 if (current_function_decl)
96 ++DECL_NUM_STMTS (current_function_decl);
97
98 return t;
99 }
100
101 /* Create a declaration statement for the declaration given by the
102 DECL. */
103
104 void
add_decl_stmt(decl)105 add_decl_stmt (decl)
106 tree decl;
107 {
108 tree decl_stmt;
109
110 /* We need the type to last until instantiation time. */
111 decl_stmt = build_stmt (DECL_STMT, decl);
112 add_stmt (decl_stmt);
113 }
114
115 /* Add a scope-statement to the statement-tree. BEGIN_P indicates
116 whether this statements opens or closes a scope. PARTIAL_P is true
117 for a partial scope, i.e, the scope that begins after a label when
118 an object that needs a cleanup is created. If BEGIN_P is nonzero,
119 returns a new TREE_LIST representing the top of the SCOPE_STMT
120 stack. The TREE_PURPOSE is the new SCOPE_STMT. If BEGIN_P is
121 zero, returns a TREE_LIST whose TREE_VALUE is the new SCOPE_STMT,
122 and whose TREE_PURPOSE is the matching SCOPE_STMT with
123 SCOPE_BEGIN_P set. */
124
125 tree
add_scope_stmt(begin_p,partial_p)126 add_scope_stmt (begin_p, partial_p)
127 int begin_p;
128 int partial_p;
129 {
130 tree *stack_ptr = current_scope_stmt_stack ();
131 tree ss;
132 tree top = *stack_ptr;
133
134 /* Build the statement. */
135 ss = build_stmt (SCOPE_STMT, NULL_TREE);
136 SCOPE_BEGIN_P (ss) = begin_p;
137 SCOPE_PARTIAL_P (ss) = partial_p;
138
139 /* Keep the scope stack up to date. */
140 if (begin_p)
141 {
142 top = tree_cons (ss, NULL_TREE, top);
143 *stack_ptr = top;
144 }
145 else
146 {
147 TREE_VALUE (top) = ss;
148 *stack_ptr = TREE_CHAIN (top);
149 }
150
151 /* Add the new statement to the statement-tree. */
152 add_stmt (ss);
153
154 return top;
155 }
156
157 /* Finish the statement tree rooted at T. */
158
159 void
finish_stmt_tree(t)160 finish_stmt_tree (t)
161 tree *t;
162 {
163 tree stmt;
164
165 /* Remove the fake extra statement added in begin_stmt_tree. */
166 stmt = TREE_CHAIN (*t);
167 *t = stmt;
168 last_tree = NULL_TREE;
169
170 if (cfun && stmt)
171 {
172 /* The line-number recorded in the outermost statement in a function
173 is the line number of the end of the function. */
174 STMT_LINENO (stmt) = lineno;
175 STMT_LINENO_FOR_FN_P (stmt) = 1;
176 }
177 }
178
179 /* Build a generic statement based on the given type of node and
180 arguments. Similar to `build_nt', except that we set
181 STMT_LINENO to be the current line number. */
182 /* ??? This should be obsolete with the lineno_stmt productions
183 in the grammar. */
184
185 tree
build_stmt(enum tree_code code,...)186 build_stmt VPARAMS ((enum tree_code code, ...))
187 {
188 tree t;
189 int length;
190 int i;
191
192 VA_OPEN (p, code);
193 VA_FIXEDARG (p, enum tree_code, code);
194
195 t = make_node (code);
196 length = TREE_CODE_LENGTH (code);
197 STMT_LINENO (t) = lineno;
198
199 for (i = 0; i < length; i++)
200 TREE_OPERAND (t, i) = va_arg (p, tree);
201
202 VA_CLOSE (p);
203 return t;
204 }
205
206 /* Some statements, like for-statements or if-statements, require a
207 condition. This condition can be a declaration. If T is such a
208 declaration it is processed, and an expression appropriate to use
209 as the condition is returned. Otherwise, T itself is returned. */
210
211 tree
expand_cond(t)212 expand_cond (t)
213 tree t;
214 {
215 if (t && TREE_CODE (t) == TREE_LIST)
216 {
217 expand_stmt (TREE_PURPOSE (t));
218 return TREE_VALUE (t);
219 }
220 else
221 return t;
222 }
223
224 /* Create RTL for the local static variable DECL. */
225
226 void
make_rtl_for_local_static(decl)227 make_rtl_for_local_static (decl)
228 tree decl;
229 {
230 const char *asmspec = NULL;
231
232 /* If we inlined this variable, we could see it's declaration
233 again. */
234 if (TREE_ASM_WRITTEN (decl))
235 return;
236
237 /* If the DECL_ASSEMBLER_NAME is not the same as the DECL_NAME, then
238 either we already created RTL for this DECL (and since it was a
239 local variable, its DECL_ASSEMBLER_NAME got hacked up to prevent
240 clashes with other local statics with the same name by a previous
241 call to make_decl_rtl), or the user explicitly requested a
242 particular assembly name for this variable, using the GNU
243 extension for this purpose:
244
245 int i asm ("j");
246
247 There's no way to know which case we're in, here. But, it turns
248 out we're safe. If there's already RTL, then
249 rest_of_decl_compilation ignores the ASMSPEC parameter, so we
250 may as well not pass it in. If there isn't RTL, then we didn't
251 already create RTL, which means that the modification to
252 DECL_ASSEMBLER_NAME came only via the explicit extension. */
253 if (DECL_ASSEMBLER_NAME (decl) != DECL_NAME (decl)
254 && !DECL_RTL_SET_P (decl))
255 asmspec = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
256
257 rest_of_decl_compilation (decl, asmspec, /*top_level=*/0, /*at_end=*/0);
258 }
259
260 /* Let the back-end know about DECL. */
261
262 void
emit_local_var(decl)263 emit_local_var (decl)
264 tree decl;
265 {
266 /* Create RTL for this variable. */
267 if (!DECL_RTL_SET_P (decl))
268 {
269 if (DECL_C_HARD_REGISTER (decl))
270 /* The user specified an assembler name for this variable.
271 Set that up now. */
272 rest_of_decl_compilation
273 (decl, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
274 /*top_level=*/0, /*at_end=*/0);
275 else
276 expand_decl (decl);
277 }
278
279 /* Actually do the initialization. */
280 if (stmts_are_full_exprs_p ())
281 expand_start_target_temps ();
282
283 expand_decl_init (decl);
284
285 if (stmts_are_full_exprs_p ())
286 expand_end_target_temps ();
287 }
288
289 /* Helper for generating the RTL at the beginning of a scope. */
290
291 void
genrtl_do_pushlevel()292 genrtl_do_pushlevel ()
293 {
294 emit_line_note (input_filename, lineno);
295 clear_last_expr ();
296 }
297
298 /* Generate the RTL for DESTINATION, which is a GOTO_STMT. */
299
300 void
genrtl_goto_stmt(destination)301 genrtl_goto_stmt (destination)
302 tree destination;
303 {
304 if (TREE_CODE (destination) == IDENTIFIER_NODE)
305 abort ();
306
307 /* We warn about unused labels with -Wunused. That means we have to
308 mark the used labels as used. */
309 if (TREE_CODE (destination) == LABEL_DECL)
310 TREE_USED (destination) = 1;
311
312 emit_line_note (input_filename, lineno);
313
314 if (TREE_CODE (destination) == LABEL_DECL)
315 {
316 label_rtx (destination);
317 expand_goto (destination);
318 }
319 else
320 expand_computed_goto (destination);
321 }
322
323 /* Generate the RTL for EXPR, which is an EXPR_STMT. Provided just
324 for backward compatibility. genrtl_expr_stmt_value() should be
325 used for new code. */
326
327 void
genrtl_expr_stmt(expr)328 genrtl_expr_stmt (expr)
329 tree expr;
330 {
331 genrtl_expr_stmt_value (expr, -1, 1);
332 }
333
334 /* Generate the RTL for EXPR, which is an EXPR_STMT. WANT_VALUE tells
335 whether to (1) save the value of the expression, (0) discard it or
336 (-1) use expr_stmts_for_value to tell. The use of -1 is
337 deprecated, and retained only for backward compatibility.
338 MAYBE_LAST is nonzero if this EXPR_STMT might be the last statement
339 in expression statement. */
340
341 void
genrtl_expr_stmt_value(expr,want_value,maybe_last)342 genrtl_expr_stmt_value (expr, want_value, maybe_last)
343 tree expr;
344 int want_value, maybe_last;
345 {
346 if (expr != NULL_TREE)
347 {
348 emit_line_note (input_filename, lineno);
349
350 if (stmts_are_full_exprs_p ())
351 expand_start_target_temps ();
352
353 if (expr != error_mark_node)
354 expand_expr_stmt_value (expr, want_value, maybe_last);
355
356 if (stmts_are_full_exprs_p ())
357 expand_end_target_temps ();
358 }
359 }
360
361 /* Generate the RTL for T, which is a DECL_STMT. */
362
363 void
genrtl_decl_stmt(t)364 genrtl_decl_stmt (t)
365 tree t;
366 {
367 tree decl;
368 emit_line_note (input_filename, lineno);
369 decl = DECL_STMT_DECL (t);
370 /* If this is a declaration for an automatic local
371 variable, initialize it. Note that we might also see a
372 declaration for a namespace-scope object (declared with
373 `extern'). We don't have to handle the initialization
374 of those objects here; they can only be declarations,
375 rather than definitions. */
376 if (TREE_CODE (decl) == VAR_DECL
377 && !TREE_STATIC (decl)
378 && !DECL_EXTERNAL (decl))
379 {
380 /* Let the back-end know about this variable. */
381 if (!anon_aggr_type_p (TREE_TYPE (decl)))
382 emit_local_var (decl);
383 else
384 expand_anon_union_decl (decl, NULL_TREE,
385 DECL_ANON_UNION_ELEMS (decl));
386 }
387 else if (TREE_CODE (decl) == VAR_DECL && TREE_STATIC (decl))
388 make_rtl_for_local_static (decl);
389 else if (TREE_CODE (decl) == LABEL_DECL
390 && C_DECLARED_LABEL_FLAG (decl))
391 declare_nonlocal_label (decl);
392 else if (lang_expand_decl_stmt)
393 (*lang_expand_decl_stmt) (t);
394 }
395
396 /* Generate the RTL for T, which is an IF_STMT. */
397
398 void
genrtl_if_stmt(t)399 genrtl_if_stmt (t)
400 tree t;
401 {
402 tree cond;
403 genrtl_do_pushlevel ();
404 cond = expand_cond (IF_COND (t));
405 emit_line_note (input_filename, lineno);
406 expand_start_cond (cond, 0);
407 if (THEN_CLAUSE (t))
408 expand_stmt (THEN_CLAUSE (t));
409 if (ELSE_CLAUSE (t))
410 {
411 expand_start_else ();
412 expand_stmt (ELSE_CLAUSE (t));
413 }
414 expand_end_cond ();
415 }
416
417 /* Generate the RTL for T, which is a WHILE_STMT. */
418
419 void
genrtl_while_stmt(t)420 genrtl_while_stmt (t)
421 tree t;
422 {
423 tree cond;
424 emit_nop ();
425 emit_line_note (input_filename, lineno);
426 expand_start_loop (1);
427 genrtl_do_pushlevel ();
428
429 cond = expand_cond (WHILE_COND (t));
430 emit_line_note (input_filename, lineno);
431 expand_exit_loop_top_cond (0, cond);
432 genrtl_do_pushlevel ();
433
434 expand_stmt (WHILE_BODY (t));
435
436 expand_end_loop ();
437 }
438
439 /* Generate the RTL for T, which is a DO_STMT. */
440
441 void
genrtl_do_stmt(t)442 genrtl_do_stmt (t)
443 tree t;
444 {
445 tree cond = DO_COND (t);
446
447 /* Recognize the common special-case of do { ... } while (0) and do
448 not emit the loop widgetry in this case. In particular this
449 avoids cluttering the rtl with dummy loop notes, which can affect
450 alignment of adjacent labels. COND can be NULL due to parse
451 errors. */
452 if (!cond || integer_zerop (cond))
453 {
454 expand_start_null_loop ();
455 expand_stmt (DO_BODY (t));
456 expand_end_null_loop ();
457 }
458 else
459 {
460 emit_nop ();
461 emit_line_note (input_filename, lineno);
462 expand_start_loop_continue_elsewhere (1);
463
464 expand_stmt (DO_BODY (t));
465
466 expand_loop_continue_here ();
467 cond = expand_cond (cond);
468 emit_line_note (input_filename, lineno);
469 expand_exit_loop_if_false (0, cond);
470 expand_end_loop ();
471 }
472 }
473
474 /* Build the node for a return statement and return it. */
475
476 tree
build_return_stmt(expr)477 build_return_stmt (expr)
478 tree expr;
479 {
480 return (build_stmt (RETURN_STMT, expr));
481 }
482
483 /* Generate the RTL for STMT, which is a RETURN_STMT. */
484
485 void
genrtl_return_stmt(stmt)486 genrtl_return_stmt (stmt)
487 tree stmt;
488 {
489 tree expr;
490
491 expr = RETURN_STMT_EXPR (stmt);
492
493 emit_line_note (input_filename, lineno);
494 if (!expr)
495 expand_null_return ();
496 else
497 {
498 expand_start_target_temps ();
499 expand_return (expr);
500 expand_end_target_temps ();
501 }
502 }
503
504 /* Generate the RTL for T, which is a FOR_STMT. */
505
506 void
genrtl_for_stmt(t)507 genrtl_for_stmt (t)
508 tree t;
509 {
510 tree cond;
511 const char *saved_filename;
512 int saved_lineno;
513
514 if (NEW_FOR_SCOPE_P (t))
515 genrtl_do_pushlevel ();
516
517 expand_stmt (FOR_INIT_STMT (t));
518
519 /* Expand the initialization. */
520 emit_nop ();
521 emit_line_note (input_filename, lineno);
522 expand_start_loop_continue_elsewhere (1);
523 genrtl_do_pushlevel ();
524 cond = expand_cond (FOR_COND (t));
525
526 /* Save the filename and line number so that we expand the FOR_EXPR
527 we can reset them back to the saved values. */
528 saved_filename = input_filename;
529 saved_lineno = lineno;
530
531 /* Expand the condition. */
532 emit_line_note (input_filename, lineno);
533 if (cond)
534 expand_exit_loop_top_cond (0, cond);
535
536 /* Expand the body. */
537 genrtl_do_pushlevel ();
538 expand_stmt (FOR_BODY (t));
539
540 /* Expand the increment expression. */
541 input_filename = saved_filename;
542 lineno = saved_lineno;
543 emit_line_note (input_filename, lineno);
544 expand_loop_continue_here ();
545 if (FOR_EXPR (t))
546 genrtl_expr_stmt (FOR_EXPR (t));
547 expand_end_loop ();
548 }
549
550 /* Build a break statement node and return it. */
551
552 tree
build_break_stmt()553 build_break_stmt ()
554 {
555 return (build_stmt (BREAK_STMT));
556 }
557
558 /* Generate the RTL for a BREAK_STMT. */
559
560 void
genrtl_break_stmt()561 genrtl_break_stmt ()
562 {
563 emit_line_note (input_filename, lineno);
564 if ( ! expand_exit_something ())
565 error ("break statement not within loop or switch");
566 }
567
568 /* Build a continue statement node and return it. */
569
570 tree
build_continue_stmt()571 build_continue_stmt ()
572 {
573 return (build_stmt (CONTINUE_STMT));
574 }
575
576 /* Generate the RTL for a CONTINUE_STMT. */
577
578 void
genrtl_continue_stmt()579 genrtl_continue_stmt ()
580 {
581 emit_line_note (input_filename, lineno);
582 if (! expand_continue_loop (0))
583 error ("continue statement not within a loop");
584 }
585
586 /* Generate the RTL for T, which is a SCOPE_STMT. */
587
588 void
genrtl_scope_stmt(t)589 genrtl_scope_stmt (t)
590 tree t;
591 {
592 tree block = SCOPE_STMT_BLOCK (t);
593
594 if (!SCOPE_NO_CLEANUPS_P (t))
595 {
596 if (SCOPE_BEGIN_P (t))
597 expand_start_bindings_and_block (2 * SCOPE_NULLIFIED_P (t), block);
598 else if (SCOPE_END_P (t))
599 expand_end_bindings (NULL_TREE, !SCOPE_NULLIFIED_P (t), 0);
600 }
601 else if (!SCOPE_NULLIFIED_P (t))
602 {
603 rtx note = emit_note (NULL,
604 (SCOPE_BEGIN_P (t)
605 ? NOTE_INSN_BLOCK_BEG
606 : NOTE_INSN_BLOCK_END));
607 NOTE_BLOCK (note) = block;
608 }
609
610 /* If we're at the end of a scope that contains inlined nested
611 functions, we have to decide whether or not to write them out. */
612 if (block && SCOPE_END_P (t))
613 {
614 tree fn;
615
616 for (fn = BLOCK_VARS (block); fn; fn = TREE_CHAIN (fn))
617 {
618 if (TREE_CODE (fn) == FUNCTION_DECL
619 && DECL_CONTEXT (fn) == current_function_decl
620 && DECL_SAVED_INSNS (fn)
621 && !TREE_ASM_WRITTEN (fn)
622 && TREE_ADDRESSABLE (fn))
623 {
624 push_function_context ();
625 output_inline_function (fn);
626 pop_function_context ();
627 }
628 }
629 }
630 }
631
632 /* Generate the RTL for T, which is a SWITCH_STMT. */
633
634 void
genrtl_switch_stmt(t)635 genrtl_switch_stmt (t)
636 tree t;
637 {
638 tree cond;
639 genrtl_do_pushlevel ();
640
641 cond = expand_cond (SWITCH_COND (t));
642 if (cond == error_mark_node)
643 /* The code is in error, but we don't want expand_end_case to
644 crash. */
645 cond = boolean_false_node;
646
647 emit_line_note (input_filename, lineno);
648 expand_start_case (1, cond, TREE_TYPE (cond), "switch statement");
649 expand_stmt (SWITCH_BODY (t));
650 expand_end_case_type (cond, SWITCH_TYPE (t));
651 }
652
653 /* Create a CASE_LABEL tree node and return it. */
654
655 tree
build_case_label(low_value,high_value,label_decl)656 build_case_label (low_value, high_value, label_decl)
657 tree low_value;
658 tree high_value;
659 tree label_decl;
660 {
661 return build_stmt (CASE_LABEL, low_value, high_value, label_decl);
662 }
663
664
665 /* Generate the RTL for a CASE_LABEL. */
666
667 void
genrtl_case_label(case_label)668 genrtl_case_label (case_label)
669 tree case_label;
670 {
671 tree duplicate;
672 tree cleanup;
673
674 cleanup = last_cleanup_this_contour ();
675 if (cleanup)
676 {
677 static int explained = 0;
678 warning ("destructor needed for `%#D'", (TREE_PURPOSE (cleanup)));
679 warning ("where case label appears here");
680 if (!explained)
681 {
682 warning ("(enclose actions of previous case statements requiring destructors in their own scope.)");
683 explained = 1;
684 }
685 }
686
687 add_case_node (CASE_LOW (case_label), CASE_HIGH (case_label),
688 CASE_LABEL_DECL (case_label), &duplicate);
689 }
690
691 /* Generate the RTL for T, which is a COMPOUND_STMT. */
692
693 void
genrtl_compound_stmt(t)694 genrtl_compound_stmt (t)
695 tree t;
696 {
697 #ifdef ENABLE_CHECKING
698 struct nesting *n = current_nesting_level ();
699 #endif
700
701 expand_stmt (COMPOUND_BODY (t));
702
703 #ifdef ENABLE_CHECKING
704 /* Make sure that we've pushed and popped the same number of levels. */
705 if (!COMPOUND_STMT_NO_SCOPE (t) && n != current_nesting_level ())
706 abort ();
707 #endif
708 }
709
710 /* Generate the RTL for an ASM_STMT. */
711
712 void
genrtl_asm_stmt(cv_qualifier,string,output_operands,input_operands,clobbers,asm_input_p)713 genrtl_asm_stmt (cv_qualifier, string, output_operands,
714 input_operands, clobbers, asm_input_p)
715 tree cv_qualifier;
716 tree string;
717 tree output_operands;
718 tree input_operands;
719 tree clobbers;
720 int asm_input_p;
721 {
722 if (cv_qualifier != NULL_TREE
723 && cv_qualifier != ridpointers[(int) RID_VOLATILE])
724 {
725 warning ("%s qualifier ignored on asm",
726 IDENTIFIER_POINTER (cv_qualifier));
727 cv_qualifier = NULL_TREE;
728 }
729
730 emit_line_note (input_filename, lineno);
731 if (asm_input_p)
732 expand_asm (string, cv_qualifier != NULL_TREE);
733 else
734 c_expand_asm_operands (string, output_operands, input_operands,
735 clobbers, cv_qualifier != NULL_TREE,
736 input_filename, lineno);
737 }
738
739 /* Generate the RTL for a DECL_CLEANUP. */
740
741 void
genrtl_decl_cleanup(t)742 genrtl_decl_cleanup (t)
743 tree t;
744 {
745 tree decl = CLEANUP_DECL (t);
746 if (!decl || (DECL_SIZE (decl) && TREE_TYPE (decl) != error_mark_node))
747 expand_decl_cleanup_eh (decl, CLEANUP_EXPR (t), CLEANUP_EH_ONLY (t));
748 }
749
750 /* We're about to expand T, a statement. Set up appropriate context
751 for the substitution. */
752
753 void
prep_stmt(t)754 prep_stmt (t)
755 tree t;
756 {
757 if (!STMT_LINENO_FOR_FN_P (t))
758 lineno = STMT_LINENO (t);
759 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
760 }
761
762 /* Generate the RTL for the statement T, its substatements, and any
763 other statements at its nesting level. */
764
765 void
expand_stmt(t)766 expand_stmt (t)
767 tree t;
768 {
769 while (t && t != error_mark_node)
770 {
771 int saved_stmts_are_full_exprs_p;
772
773 /* Set up context appropriately for handling this statement. */
774 saved_stmts_are_full_exprs_p = stmts_are_full_exprs_p ();
775 prep_stmt (t);
776
777 switch (TREE_CODE (t))
778 {
779 case FILE_STMT:
780 input_filename = FILE_STMT_FILENAME (t);
781 break;
782
783 case RETURN_STMT:
784 genrtl_return_stmt (t);
785 break;
786
787 case EXPR_STMT:
788 genrtl_expr_stmt_value (EXPR_STMT_EXPR (t), TREE_ADDRESSABLE (t),
789 TREE_CHAIN (t) == NULL
790 || (TREE_CODE (TREE_CHAIN (t)) == SCOPE_STMT
791 && TREE_CHAIN (TREE_CHAIN (t)) == NULL));
792 break;
793
794 case DECL_STMT:
795 genrtl_decl_stmt (t);
796 break;
797
798 case FOR_STMT:
799 genrtl_for_stmt (t);
800 break;
801
802 case WHILE_STMT:
803 genrtl_while_stmt (t);
804 break;
805
806 case DO_STMT:
807 genrtl_do_stmt (t);
808 break;
809
810 case IF_STMT:
811 genrtl_if_stmt (t);
812 break;
813
814 case COMPOUND_STMT:
815 genrtl_compound_stmt (t);
816 break;
817
818 case BREAK_STMT:
819 genrtl_break_stmt ();
820 break;
821
822 case CONTINUE_STMT:
823 genrtl_continue_stmt ();
824 break;
825
826 case SWITCH_STMT:
827 genrtl_switch_stmt (t);
828 break;
829
830 case CASE_LABEL:
831 genrtl_case_label (t);
832 break;
833
834 case LABEL_STMT:
835 expand_label (LABEL_STMT_LABEL (t));
836 break;
837
838 case GOTO_STMT:
839 /* Emit information for branch prediction. */
840 if (!GOTO_FAKE_P (t)
841 && TREE_CODE (GOTO_DESTINATION (t)) == LABEL_DECL
842 && flag_guess_branch_prob)
843 {
844 rtx note = emit_note (NULL, NOTE_INSN_PREDICTION);
845
846 NOTE_PREDICTION (note) = NOTE_PREDICT (PRED_GOTO, NOT_TAKEN);
847 }
848 genrtl_goto_stmt (GOTO_DESTINATION (t));
849 break;
850
851 case ASM_STMT:
852 genrtl_asm_stmt (ASM_CV_QUAL (t), ASM_STRING (t),
853 ASM_OUTPUTS (t), ASM_INPUTS (t),
854 ASM_CLOBBERS (t), ASM_INPUT_P (t));
855 break;
856
857 case SCOPE_STMT:
858 genrtl_scope_stmt (t);
859 break;
860
861 case CLEANUP_STMT:
862 genrtl_decl_cleanup (t);
863 break;
864
865 default:
866 if (lang_expand_stmt)
867 (*lang_expand_stmt) (t);
868 else
869 abort ();
870 break;
871 }
872
873 /* Restore saved state. */
874 current_stmt_tree ()->stmts_are_full_exprs_p
875 = saved_stmts_are_full_exprs_p;
876
877 /* Go on to the next statement in this scope. */
878 t = TREE_CHAIN (t);
879 }
880 }
881