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Merge branches 'quiets-bool-cast-restricted-v2', 'keyword-cleanup-v2', 'not-so-crazy...
[smatch.git] / linearize.c
bloba36ab48c36e04261b005ee33278df5a707dafa5f
1 /*
2 * Linearize - walk the statement tree (but _not_ the expressions)
3 * to generate a linear version of it and the basic blocks.
4 *
5 * NOTE! We're not interested in the actual sub-expressions yet,
6 * even though they can generate conditional branches and
7 * subroutine calls. That's all "local" behaviour.
8 *
9 * Copyright (C) 2004 Linus Torvalds
10 * Copyright (C) 2004 Christopher Li
11 */
12
13 #include <string.h>
14 #include <stdarg.h>
15 #include <stdlib.h>
16 #include <stdio.h>
17 #include <assert.h>
18
19 #include "parse.h"
20 #include "expression.h"
21 #include "linearize.h"
22 #include "flow.h"
23 #include "target.h"
24
25 pseudo_t linearize_statement(struct entrypoint *ep, struct statement *stmt);
26 pseudo_t linearize_expression(struct entrypoint *ep, struct expression *expr);
27
28 static pseudo_t add_binary_op(struct entrypoint *ep, struct symbol *ctype, int op, pseudo_t left, pseudo_t right);
29 static pseudo_t add_setval(struct entrypoint *ep, struct symbol *ctype, struct expression *val);
30 static pseudo_t linearize_one_symbol(struct entrypoint *ep, struct symbol *sym);
31
32 struct access_data;
33 static pseudo_t add_load(struct entrypoint *ep, struct access_data *);
34 static pseudo_t linearize_initializer(struct entrypoint *ep, struct expression *initializer, struct access_data *);
35 static pseudo_t cast_pseudo(struct entrypoint *ep, pseudo_t src, struct symbol *from, struct symbol *to);
36
37 struct pseudo void_pseudo = {};
38
39 static struct position current_pos;
40
41 ALLOCATOR(pseudo_user, "pseudo_user");
42
43 static struct instruction *alloc_instruction(int opcode, int size)
44 {
45 struct instruction * insn = __alloc_instruction(0);
46 insn->opcode = opcode;
47 insn->size = size;
48 insn->pos = current_pos;
49 return insn;
50 }
51
52 static inline int type_size(struct symbol *type)
53 {
54 return type ? type->bit_size > 0 ? type->bit_size : 0 : 0;
55 }
56
57 static struct instruction *alloc_typed_instruction(int opcode, struct symbol *type)
58 {
59 struct instruction *insn = alloc_instruction(opcode, type_size(type));
60 insn->type = type;
61 return insn;
62 }
63
64 static struct entrypoint *alloc_entrypoint(void)
65 {
66 return __alloc_entrypoint(0);
67 }
68
69 static struct basic_block *alloc_basic_block(struct entrypoint *ep, struct position pos)
70 {
71 static int nr;
72 struct basic_block *bb = __alloc_basic_block(0);
73 bb->context = -1;
74 bb->pos = pos;
75 bb->ep = ep;
76 bb->nr = nr++;
77 return bb;
78 }
79
80 static struct multijmp *alloc_multijmp(struct basic_block *target, int begin, int end)
81 {
82 struct multijmp *multijmp = __alloc_multijmp(0);
83 multijmp->target = target;
84 multijmp->begin = begin;
85 multijmp->end = end;
86 return multijmp;
87 }
88
89 static inline int regno(pseudo_t n)
90 {
91 int retval = -1;
92 if (n && n->type == PSEUDO_REG)
93 retval = n->nr;
94 return retval;
95 }
96
97 const char *show_pseudo(pseudo_t pseudo)
98 {
99 static int n;
100 static char buffer[4][64];
101 char *buf;
102 int i;
103
104 if (!pseudo)
105 return "no pseudo";
106 if (pseudo == VOID)
107 return "VOID";
108 buf = buffer[3 & ++n];
109 switch(pseudo->type) {
110 case PSEUDO_SYM: {
111 struct symbol *sym = pseudo->sym;
112 struct expression *expr;
113
114 if (sym->bb_target) {
115 snprintf(buf, 64, ".L%u", sym->bb_target->nr);
116 break;
117 }
118 if (sym->ident) {
119 snprintf(buf, 64, "%s", show_ident(sym->ident));
120 break;
121 }
122 expr = sym->initializer;
123 snprintf(buf, 64, "<anon symbol:%p>", sym);
124 if (expr) {
125 switch (expr->type) {
126 case EXPR_VALUE:
127 snprintf(buf, 64, "<symbol value: %lld>", expr->value);
128 break;
129 case EXPR_STRING:
130 return show_string(expr->string);
131 default:
132 break;
133 }
134 }
135 break;
136 }
137 case PSEUDO_REG:
138 i = snprintf(buf, 64, "%%r%d", pseudo->nr);
139 if (pseudo->ident)
140 sprintf(buf+i, "(%s)", show_ident(pseudo->ident));
141 break;
142 case PSEUDO_VAL: {
143 long long value = pseudo->value;
144 if (value > 1000 || value < -1000)
145 snprintf(buf, 64, "$%#llx", value);
146 else
147 snprintf(buf, 64, "$%lld", value);
148 break;
149 }
150 case PSEUDO_ARG:
151 snprintf(buf, 64, "%%arg%d", pseudo->nr);
152 break;
153 case PSEUDO_PHI:
154 i = snprintf(buf, 64, "%%phi%d", pseudo->nr);
155 if (pseudo->ident)
156 sprintf(buf+i, "(%s)", show_ident(pseudo->ident));
157 break;
158 default:
159 snprintf(buf, 64, "<bad pseudo type %d>", pseudo->type);
160 }
161 return buf;
162 }
163
164 static const char *opcodes[] = {
165 [OP_BADOP] = "bad_op",
166
167 /* Fn entrypoint */
168 [OP_ENTRY] = "<entry-point>",
169
170 /* Terminator */
171 [OP_RET] = "ret",
172 [OP_BR] = "br",
173 [OP_CBR] = "cbr",
174 [OP_SWITCH] = "switch",
175 [OP_INVOKE] = "invoke",
176 [OP_COMPUTEDGOTO] = "jmp *",
177 [OP_UNWIND] = "unwind",
178
179 /* Binary */
180 [OP_ADD] = "add",
181 [OP_SUB] = "sub",
182 [OP_MULU] = "mulu",
183 [OP_MULS] = "muls",
184 [OP_DIVU] = "divu",
185 [OP_DIVS] = "divs",
186 [OP_MODU] = "modu",
187 [OP_MODS] = "mods",
188 [OP_SHL] = "shl",
189 [OP_LSR] = "lsr",
190 [OP_ASR] = "asr",
191
192 /* Logical */
193 [OP_AND] = "and",
194 [OP_OR] = "or",
195 [OP_XOR] = "xor",
196 [OP_AND_BOOL] = "and-bool",
197 [OP_OR_BOOL] = "or-bool",
198
199 /* Binary comparison */
200 [OP_SET_EQ] = "seteq",
201 [OP_SET_NE] = "setne",
202 [OP_SET_LE] = "setle",
203 [OP_SET_GE] = "setge",
204 [OP_SET_LT] = "setlt",
205 [OP_SET_GT] = "setgt",
206 [OP_SET_B] = "setb",
207 [OP_SET_A] = "seta",
208 [OP_SET_BE] = "setbe",
209 [OP_SET_AE] = "setae",
210
211 /* Uni */
212 [OP_NOT] = "not",
213 [OP_NEG] = "neg",
214
215 /* Special three-input */
216 [OP_SEL] = "select",
217
218 /* Memory */
219 [OP_MALLOC] = "malloc",
220 [OP_FREE] = "free",
221 [OP_ALLOCA] = "alloca",
222 [OP_LOAD] = "load",
223 [OP_STORE] = "store",
224 [OP_SETVAL] = "set",
225 [OP_SYMADDR] = "symaddr",
226 [OP_GET_ELEMENT_PTR] = "getelem",
227
228 /* Other */
229 [OP_PHI] = "phi",
230 [OP_PHISOURCE] = "phisrc",
231 [OP_CAST] = "cast",
232 [OP_SCAST] = "scast",
233 [OP_FPCAST] = "fpcast",
234 [OP_PTRCAST] = "ptrcast",
235 [OP_INLINED_CALL] = "# call",
236 [OP_CALL] = "call",
237 [OP_VANEXT] = "va_next",
238 [OP_VAARG] = "va_arg",
239 [OP_SLICE] = "slice",
240 [OP_SNOP] = "snop",
241 [OP_LNOP] = "lnop",
242 [OP_NOP] = "nop",
243 [OP_DEATHNOTE] = "dead",
244 [OP_ASM] = "asm",
245
246 /* Sparse tagging (line numbers, context, whatever) */
247 [OP_CONTEXT] = "context",
248 [OP_RANGE] = "range-check",
249
250 [OP_COPY] = "copy",
251 };
252
253 static char *show_asm_constraints(char *buf, const char *sep, struct asm_constraint_list *list)
254 {
255 struct asm_constraint *entry;
256
257 FOR_EACH_PTR(list, entry) {
258 buf += sprintf(buf, "%s\"%s\"", sep, entry->constraint);
259 if (entry->pseudo)
260 buf += sprintf(buf, " (%s)", show_pseudo(entry->pseudo));
261 if (entry->ident)
262 buf += sprintf(buf, " [%s]", show_ident(entry->ident));
263 sep = ", ";
264 } END_FOR_EACH_PTR(entry);
265 return buf;
266 }
267
268 static char *show_asm(char *buf, struct instruction *insn)
269 {
270 struct asm_rules *rules = insn->asm_rules;
271
272 buf += sprintf(buf, "\"%s\"", insn->string);
273 buf = show_asm_constraints(buf, "\n\t\tout: ", rules->outputs);
274 buf = show_asm_constraints(buf, "\n\t\tin: ", rules->inputs);
275 buf = show_asm_constraints(buf, "\n\t\tclobber: ", rules->clobbers);
276 return buf;
277 }
278
279 const char *show_instruction(struct instruction *insn)
280 {
281 int opcode = insn->opcode;
282 static char buffer[4096];
283 char *buf;
284
285 buf = buffer;
286 if (!insn->bb)
287 buf += sprintf(buf, "# ");
288
289 if (opcode < ARRAY_SIZE(opcodes)) {
290 const char *op = opcodes[opcode];
291 if (!op)
292 buf += sprintf(buf, "opcode:%d", opcode);
293 else
294 buf += sprintf(buf, "%s", op);
295 if (insn->size)
296 buf += sprintf(buf, ".%d", insn->size);
297 memset(buf, ' ', 20);
298 buf++;
299 }
300
301 if (buf < buffer + 12)
302 buf = buffer + 12;
303 switch (opcode) {
304 case OP_RET:
305 if (insn->src && insn->src != VOID)
306 buf += sprintf(buf, "%s", show_pseudo(insn->src));
307 break;
308
309 case OP_CBR:
310 buf += sprintf(buf, "%s, .L%u, .L%u", show_pseudo(insn->cond), insn->bb_true->nr, insn->bb_false->nr);
311 break;
312
313 case OP_BR:
314 buf += sprintf(buf, ".L%u", insn->bb_true->nr);
315 break;
316
317 case OP_SYMADDR: {
318 struct symbol *sym = insn->symbol->sym;
319 buf += sprintf(buf, "%s <- ", show_pseudo(insn->target));
320
321 if (!insn->bb && !sym)
322 break;
323 if (sym->bb_target) {
324 buf += sprintf(buf, ".L%u", sym->bb_target->nr);
325 break;
326 }
327 if (sym->ident) {
328 buf += sprintf(buf, "%s", show_ident(sym->ident));
329 break;
330 }
331 buf += sprintf(buf, "<anon symbol:%p>", sym);
332 break;
333 }
334
335 case OP_SETVAL: {
336 struct expression *expr = insn->val;
337 buf += sprintf(buf, "%s <- ", show_pseudo(insn->target));
338
339 if (!expr) {
340 buf += sprintf(buf, "%s", "<none>");
341 break;
342 }
343
344 switch (expr->type) {
345 case EXPR_VALUE:
346 buf += sprintf(buf, "%lld", expr->value);
347 break;
348 case EXPR_FVALUE:
349 buf += sprintf(buf, "%Lf", expr->fvalue);
350 break;
351 case EXPR_STRING:
352 buf += sprintf(buf, "%.40s", show_string(expr->string));
353 break;
354 case EXPR_SYMBOL:
355 buf += sprintf(buf, "%s", show_ident(expr->symbol->ident));
356 break;
357 case EXPR_LABEL:
358 buf += sprintf(buf, ".L%u", expr->symbol->bb_target->nr);
359 break;
360 default:
361 buf += sprintf(buf, "SETVAL EXPR TYPE %d", expr->type);
362 }
363 break;
364 }
365 case OP_SWITCH: {
366 struct multijmp *jmp;
367 buf += sprintf(buf, "%s", show_pseudo(insn->cond));
368 FOR_EACH_PTR(insn->multijmp_list, jmp) {
369 if (jmp->begin == jmp->end)
370 buf += sprintf(buf, ", %d -> .L%u", jmp->begin, jmp->target->nr);
371 else if (jmp->begin < jmp->end)
372 buf += sprintf(buf, ", %d ... %d -> .L%u", jmp->begin, jmp->end, jmp->target->nr);
373 else
374 buf += sprintf(buf, ", default -> .L%u", jmp->target->nr);
375 } END_FOR_EACH_PTR(jmp);
376 break;
377 }
378 case OP_COMPUTEDGOTO: {
379 struct multijmp *jmp;
380 buf += sprintf(buf, "%s", show_pseudo(insn->target));
381 FOR_EACH_PTR(insn->multijmp_list, jmp) {
382 buf += sprintf(buf, ", .L%u", jmp->target->nr);
383 } END_FOR_EACH_PTR(jmp);
384 break;
385 }
386
387 case OP_PHISOURCE: {
388 struct instruction *phi;
389 buf += sprintf(buf, "%s <- %s ", show_pseudo(insn->target), show_pseudo(insn->phi_src));
390 FOR_EACH_PTR(insn->phi_users, phi) {
391 buf += sprintf(buf, " (%s)", show_pseudo(phi->target));
392 } END_FOR_EACH_PTR(phi);
393 break;
394 }
395
396 case OP_PHI: {
397 pseudo_t phi;
398 const char *s = " <-";
399 buf += sprintf(buf, "%s", show_pseudo(insn->target));
400 FOR_EACH_PTR(insn->phi_list, phi) {
401 buf += sprintf(buf, "%s %s", s, show_pseudo(phi));
402 s = ",";
403 } END_FOR_EACH_PTR(phi);
404 break;
405 }
406 case OP_LOAD: case OP_LNOP:
407 buf += sprintf(buf, "%s <- %d[%s]", show_pseudo(insn->target), insn->offset, show_pseudo(insn->src));
408 break;
409 case OP_STORE: case OP_SNOP:
410 buf += sprintf(buf, "%s -> %d[%s]", show_pseudo(insn->target), insn->offset, show_pseudo(insn->src));
411 break;
412 case OP_INLINED_CALL:
413 case OP_CALL: {
414 struct pseudo *arg;
415 if (insn->target && insn->target != VOID)
416 buf += sprintf(buf, "%s <- ", show_pseudo(insn->target));
417 buf += sprintf(buf, "%s", show_pseudo(insn->func));
418 FOR_EACH_PTR(insn->arguments, arg) {
419 buf += sprintf(buf, ", %s", show_pseudo(arg));
420 } END_FOR_EACH_PTR(arg);
421 break;
422 }
423 case OP_CAST:
424 case OP_SCAST:
425 case OP_FPCAST:
426 case OP_PTRCAST:
427 buf += sprintf(buf, "%s <- (%d) %s",
428 show_pseudo(insn->target),
429 type_size(insn->orig_type),
430 show_pseudo(insn->src));
431 break;
432 case OP_BINARY ... OP_BINARY_END:
433 case OP_BINCMP ... OP_BINCMP_END:
434 buf += sprintf(buf, "%s <- %s, %s", show_pseudo(insn->target), show_pseudo(insn->src1), show_pseudo(insn->src2));
435 break;
436
437 case OP_SEL:
438 buf += sprintf(buf, "%s <- %s, %s, %s", show_pseudo(insn->target),
439 show_pseudo(insn->src1), show_pseudo(insn->src2), show_pseudo(insn->src3));
440 break;
441
442 case OP_SLICE:
443 buf += sprintf(buf, "%s <- %s, %d, %d", show_pseudo(insn->target), show_pseudo(insn->base), insn->from, insn->len);
444 break;
445
446 case OP_NOT: case OP_NEG:
447 buf += sprintf(buf, "%s <- %s", show_pseudo(insn->target), show_pseudo(insn->src1));
448 break;
449
450 case OP_CONTEXT:
451 buf += sprintf(buf, "%s%d", insn->check ? "check: " : "", insn->increment);
452 break;
453 case OP_RANGE:
454 buf += sprintf(buf, "%s between %s..%s", show_pseudo(insn->src1), show_pseudo(insn->src2), show_pseudo(insn->src3));
455 break;
456 case OP_NOP:
457 buf += sprintf(buf, "%s <- %s", show_pseudo(insn->target), show_pseudo(insn->src1));
458 break;
459 case OP_DEATHNOTE:
460 buf += sprintf(buf, "%s", show_pseudo(insn->target));
461 break;
462 case OP_ASM:
463 buf = show_asm(buf, insn);
464 break;
465 case OP_COPY:
466 buf += sprintf(buf, "%s <- %s", show_pseudo(insn->target), show_pseudo(insn->src));
467 break;
468 default:
469 break;
470 }
471
472 if (buf >= buffer + sizeof(buffer))
473 die("instruction buffer overflowed %td\n", buf - buffer);
474 do { --buf; } while (*buf == ' ');
475 *++buf = 0;
476 return buffer;
477 }
478
479 void show_bb(struct basic_block *bb)
480 {
481 struct instruction *insn;
482
483 printf(".L%u:\n", bb->nr);
484 if (verbose) {
485 pseudo_t needs, defines;
486 printf("%s:%d\n", stream_name(bb->pos.stream), bb->pos.line);
487
488 FOR_EACH_PTR(bb->needs, needs) {
489 struct instruction *def = needs->def;
490 if (def->opcode != OP_PHI) {
491 printf(" **uses %s (from .L%u)**\n", show_pseudo(needs), def->bb->nr);
492 } else {
493 pseudo_t phi;
494 const char *sep = " ";
495 printf(" **uses %s (from", show_pseudo(needs));
496 FOR_EACH_PTR(def->phi_list, phi) {
497 if (phi == VOID)
498 continue;
499 printf("%s(%s:.L%u)", sep, show_pseudo(phi), phi->def->bb->nr);
500 sep = ", ";
501 } END_FOR_EACH_PTR(phi);
502 printf(")**\n");
503 }
504 } END_FOR_EACH_PTR(needs);
505
506 FOR_EACH_PTR(bb->defines, defines) {
507 printf(" **defines %s **\n", show_pseudo(defines));
508 } END_FOR_EACH_PTR(defines);
509
510 if (bb->parents) {
511 struct basic_block *from;
512 FOR_EACH_PTR(bb->parents, from) {
513 printf(" **from .L%u (%s:%d:%d)**\n", from->nr,
514 stream_name(from->pos.stream), from->pos.line, from->pos.pos);
515 } END_FOR_EACH_PTR(from);
516 }
517
518 if (bb->children) {
519 struct basic_block *to;
520 FOR_EACH_PTR(bb->children, to) {
521 printf(" **to .L%u (%s:%d:%d)**\n", to->nr,
522 stream_name(to->pos.stream), to->pos.line, to->pos.pos);
523 } END_FOR_EACH_PTR(to);
524 }
525 }
526
527 FOR_EACH_PTR(bb->insns, insn) {
528 if (!insn->bb && verbose < 2)
529 continue;
530 printf("\t%s\n", show_instruction(insn));
531 } END_FOR_EACH_PTR(insn);
532 if (!bb_terminated(bb))
533 printf("\tEND\n");
534 }
535
536 static void show_symbol_usage(pseudo_t pseudo)
537 {
538 struct pseudo_user *pu;
539
540 if (pseudo) {
541 FOR_EACH_PTR(pseudo->users, pu) {
542 printf("\t%s\n", show_instruction(pu->insn));
543 } END_FOR_EACH_PTR(pu);
544 }
545 }
546
547 void show_entry(struct entrypoint *ep)
548 {
549 struct symbol *sym;
550 struct basic_block *bb;
551
552 printf("%s:\n", show_ident(ep->name->ident));
553
554 if (verbose) {
555 printf("ep %p: %s\n", ep, show_ident(ep->name->ident));
556
557 FOR_EACH_PTR(ep->syms, sym) {
558 if (!sym->pseudo)
559 continue;
560 if (!sym->pseudo->users)
561 continue;
562 printf(" sym: %p %s\n", sym, show_ident(sym->ident));
563 if (sym->ctype.modifiers & (MOD_EXTERN | MOD_STATIC | MOD_ADDRESSABLE))
564 printf("\texternal visibility\n");
565 show_symbol_usage(sym->pseudo);
566 } END_FOR_EACH_PTR(sym);
567
568 printf("\n");
569 }
570
571 FOR_EACH_PTR(ep->bbs, bb) {
572 if (!bb)
573 continue;
574 if (!bb->parents && !bb->children && !bb->insns && verbose < 2)
575 continue;
576 show_bb(bb);
577 printf("\n");
578 } END_FOR_EACH_PTR(bb);
579
580 printf("\n");
581 }
582
583 static void bind_label(struct symbol *label, struct basic_block *bb, struct position pos)
584 {
585 if (label->bb_target)
586 warning(pos, "label '%s' already bound", show_ident(label->ident));
587 label->bb_target = bb;
588 }
589
590 static struct basic_block * get_bound_block(struct entrypoint *ep, struct symbol *label)
591 {
592 struct basic_block *bb = label->bb_target;
593
594 if (!bb) {
595 bb = alloc_basic_block(ep, label->pos);
596 label->bb_target = bb;
597 }
598 return bb;
599 }
600
601 static void finish_block(struct entrypoint *ep)
602 {
603 struct basic_block *src = ep->active;
604 if (bb_reachable(src))
605 ep->active = NULL;
606 }
607
608 static void add_goto(struct entrypoint *ep, struct basic_block *dst)
609 {
610 struct basic_block *src = ep->active;
611 if (bb_reachable(src)) {
612 struct instruction *br = alloc_instruction(OP_BR, 0);
613 br->bb_true = dst;
614 add_bb(&dst->parents, src);
615 add_bb(&src->children, dst);
616 br->bb = src;
617 add_instruction(&src->insns, br);
618 ep->active = NULL;
619 }
620 }
621
622 static void add_one_insn(struct entrypoint *ep, struct instruction *insn)
623 {
624 struct basic_block *bb = ep->active;
625
626 if (bb_reachable(bb)) {
627 insn->bb = bb;
628 add_instruction(&bb->insns, insn);
629 }
630 }
631
632 static void set_activeblock(struct entrypoint *ep, struct basic_block *bb)
633 {
634 if (!bb_terminated(ep->active))
635 add_goto(ep, bb);
636
637 ep->active = bb;
638 if (bb_reachable(bb))
639 add_bb(&ep->bbs, bb);
640 }
641
642 static void remove_parent(struct basic_block *child, struct basic_block *parent)
643 {
644 remove_bb_from_list(&child->parents, parent, 1);
645 if (!child->parents)
646 repeat_phase |= REPEAT_CFG_CLEANUP;
647 }
648
649 /* Change a "switch" into a branch */
650 void insert_branch(struct basic_block *bb, struct instruction *jmp, struct basic_block *target)
651 {
652 struct instruction *br, *old;
653 struct basic_block *child;
654
655 /* Remove the switch */
656 old = delete_last_instruction(&bb->insns);
657 assert(old == jmp);
658
659 br = alloc_instruction(OP_BR, 0);
660 br->bb = bb;
661 br->bb_true = target;
662 add_instruction(&bb->insns, br);
663
664 FOR_EACH_PTR(bb->children, child) {
665 if (child == target) {
666 target = NULL; /* Trigger just once */
667 continue;
668 }
669 DELETE_CURRENT_PTR(child);
670 remove_parent(child, bb);
671 } END_FOR_EACH_PTR(child);
672 PACK_PTR_LIST(&bb->children);
673
674 if (repeat_phase & REPEAT_CFG_CLEANUP)
675 kill_unreachable_bbs(bb->ep);
676 }
677
678
679 void insert_select(struct basic_block *bb, struct instruction *br, struct instruction *phi_node, pseudo_t if_true, pseudo_t if_false)
680 {
681 pseudo_t target;
682 struct instruction *select;
683
684 /* Remove the 'br' */
685 delete_last_instruction(&bb->insns);
686
687 select = alloc_instruction(OP_SEL, phi_node->size);
688 select->bb = bb;
689
690 assert(br->cond);
691 use_pseudo(select, br->cond, &select->src1);
692
693 target = phi_node->target;
694 assert(target->def == phi_node);
695 select->target = target;
696 target->def = select;
697
698 use_pseudo(select, if_true, &select->src2);
699 use_pseudo(select, if_false, &select->src3);
700
701 add_instruction(&bb->insns, select);
702 add_instruction(&bb->insns, br);
703 }
704
705 static inline int bb_empty(struct basic_block *bb)
706 {
707 return !bb->insns;
708 }
709
710 /* Add a label to the currently active block, return new active block */
711 static struct basic_block * add_label(struct entrypoint *ep, struct symbol *label)
712 {
713 struct basic_block *bb = label->bb_target;
714
715 if (bb) {
716 set_activeblock(ep, bb);
717 return bb;
718 }
719 bb = ep->active;
720 if (!bb_reachable(bb) || !bb_empty(bb)) {
721 bb = alloc_basic_block(ep, label->pos);
722 set_activeblock(ep, bb);
723 }
724 label->bb_target = bb;
725 return bb;
726 }
727
728 static void add_branch(struct entrypoint *ep, struct expression *expr, pseudo_t cond, struct basic_block *bb_true, struct basic_block *bb_false)
729 {
730 struct basic_block *bb = ep->active;
731 struct instruction *br;
732
733 if (bb_reachable(bb)) {
734 br = alloc_instruction(OP_CBR, 0);
735 use_pseudo(br, cond, &br->cond);
736 br->bb_true = bb_true;
737 br->bb_false = bb_false;
738 add_bb(&bb_true->parents, bb);
739 add_bb(&bb_false->parents, bb);
740 add_bb(&bb->children, bb_true);
741 add_bb(&bb->children, bb_false);
742 add_one_insn(ep, br);
743 }
744 }
745
746 /* Dummy pseudo allocator */
747 pseudo_t alloc_pseudo(struct instruction *def)
748 {
749 static int nr = 0;
750 struct pseudo * pseudo = __alloc_pseudo(0);
751 pseudo->type = PSEUDO_REG;
752 pseudo->nr = ++nr;
753 pseudo->def = def;
754 return pseudo;
755 }
756
757 static void clear_symbol_pseudos(struct entrypoint *ep)
758 {
759 pseudo_t pseudo;
760
761 FOR_EACH_PTR(ep->accesses, pseudo) {
762 pseudo->sym->pseudo = NULL;
763 } END_FOR_EACH_PTR(pseudo);
764 }
765
766 static pseudo_t symbol_pseudo(struct entrypoint *ep, struct symbol *sym)
767 {
768 pseudo_t pseudo;
769
770 if (!sym)
771 return VOID;
772
773 pseudo = sym->pseudo;
774 if (!pseudo) {
775 pseudo = __alloc_pseudo(0);
776 pseudo->nr = -1;
777 pseudo->type = PSEUDO_SYM;
778 pseudo->sym = sym;
779 pseudo->ident = sym->ident;
780 sym->pseudo = pseudo;
781 add_pseudo(&ep->accesses, pseudo);
782 }
783 /* Symbol pseudos have neither nr, usage nor def */
784 return pseudo;
785 }
786
787 pseudo_t value_pseudo(long long val)
788 {
789 #define MAX_VAL_HASH 64
790 static struct pseudo_list *prev[MAX_VAL_HASH];
791 int hash = val & (MAX_VAL_HASH-1);
792 struct pseudo_list **list = prev + hash;
793 pseudo_t pseudo;
794
795 FOR_EACH_PTR(*list, pseudo) {
796 if (pseudo->value == val)
797 return pseudo;
798 } END_FOR_EACH_PTR(pseudo);
799
800 pseudo = __alloc_pseudo(0);
801 pseudo->type = PSEUDO_VAL;
802 pseudo->value = val;
803 add_pseudo(list, pseudo);
804
805 /* Value pseudos have neither nr, usage nor def */
806 return pseudo;
807 }
808
809 static pseudo_t argument_pseudo(struct entrypoint *ep, int nr)
810 {
811 pseudo_t pseudo = __alloc_pseudo(0);
812 struct instruction *entry = ep->entry;
813
814 pseudo->type = PSEUDO_ARG;
815 pseudo->nr = nr;
816 pseudo->def = entry;
817 add_pseudo(&entry->arg_list, pseudo);
818
819 /* Argument pseudos have neither usage nor def */
820 return pseudo;
821 }
822
823 pseudo_t alloc_phi(struct basic_block *source, pseudo_t pseudo, int size)
824 {
825 struct instruction *insn = alloc_instruction(OP_PHISOURCE, size);
826 pseudo_t phi = __alloc_pseudo(0);
827 static int nr = 0;
828
829 phi->type = PSEUDO_PHI;
830 phi->nr = ++nr;
831 phi->def = insn;
832
833 use_pseudo(insn, pseudo, &insn->phi_src);
834 insn->bb = source;
835 insn->target = phi;
836 add_instruction(&source->insns, insn);
837 return phi;
838 }
839
840 /*
841 * We carry the "access_data" structure around for any accesses,
842 * which simplifies things a lot. It contains all the access
843 * information in one place.
844 */
845 struct access_data {
846 struct symbol *result_type; // result ctype
847 struct symbol *source_type; // source ctype
848 pseudo_t address; // pseudo containing address ..
849 pseudo_t origval; // pseudo for original value ..
850 unsigned int offset, alignment; // byte offset
851 unsigned int bit_size, bit_offset; // which bits
852 struct position pos;
853 };
854
855 static void finish_address_gen(struct entrypoint *ep, struct access_data *ad)
856 {
857 }
858
859 static int linearize_simple_address(struct entrypoint *ep,
860 struct expression *addr,
861 struct access_data *ad)
862 {
863 if (addr->type == EXPR_SYMBOL) {
864 linearize_one_symbol(ep, addr->symbol);
865 ad->address = symbol_pseudo(ep, addr->symbol);
866 return 1;
867 }
868 if (addr->type == EXPR_BINOP) {
869 if (addr->right->type == EXPR_VALUE) {
870 if (addr->op == '+') {
871 ad->offset += get_expression_value(addr->right);
872 return linearize_simple_address(ep, addr->left, ad);
873 }
874 }
875 }
876 ad->address = linearize_expression(ep, addr);
877 return 1;
878 }
879
880 static struct symbol *base_type(struct symbol *sym)
881 {
882 struct symbol *base = sym;
883
884 if (sym) {
885 if (sym->type == SYM_NODE)
886 base = base->ctype.base_type;
887 if (base->type == SYM_BITFIELD)
888 return base->ctype.base_type;
889 }
890 return sym;
891 }
892
893 static int linearize_address_gen(struct entrypoint *ep,
894 struct expression *expr,
895 struct access_data *ad)
896 {
897 struct symbol *ctype = expr->ctype;
898
899 if (!ctype)
900 return 0;
901 ad->pos = expr->pos;
902 ad->result_type = ctype;
903 ad->source_type = base_type(ctype);
904 ad->bit_size = ctype->bit_size;
905 ad->alignment = ctype->ctype.alignment;
906 ad->bit_offset = ctype->bit_offset;
907 if (expr->type == EXPR_PREOP && expr->op == '*')
908 return linearize_simple_address(ep, expr->unop, ad);
909
910 warning(expr->pos, "generating address of non-lvalue (%d)", expr->type);
911 return 0;
912 }
913
914 static pseudo_t add_load(struct entrypoint *ep, struct access_data *ad)
915 {
916 struct instruction *insn;
917 pseudo_t new;
918
919 new = ad->origval;
920 if (0 && new)
921 return new;
922
923 insn = alloc_typed_instruction(OP_LOAD, ad->source_type);
924 new = alloc_pseudo(insn);
925 ad->origval = new;
926
927 insn->target = new;
928 insn->offset = ad->offset;
929 use_pseudo(insn, ad->address, &insn->src);
930 add_one_insn(ep, insn);
931 return new;
932 }
933
934 static void add_store(struct entrypoint *ep, struct access_data *ad, pseudo_t value)
935 {
936 struct basic_block *bb = ep->active;
937
938 if (bb_reachable(bb)) {
939 struct instruction *store = alloc_typed_instruction(OP_STORE, ad->source_type);
940 store->offset = ad->offset;
941 use_pseudo(store, value, &store->target);
942 use_pseudo(store, ad->address, &store->src);
943 add_one_insn(ep, store);
944 }
945 }
946
947 static pseudo_t linearize_store_gen(struct entrypoint *ep,
948 pseudo_t value,
949 struct access_data *ad)
950 {
951 pseudo_t store = value;
952
953 if (type_size(ad->source_type) != type_size(ad->result_type)) {
954 pseudo_t orig = add_load(ep, ad);
955 int shift = ad->bit_offset;
956 unsigned long long mask = (1ULL << ad->bit_size)-1;
957
958 if (shift) {
959 store = add_binary_op(ep, ad->source_type, OP_SHL, value, value_pseudo(shift));
960 mask <<= shift;
961 }
962 orig = add_binary_op(ep, ad->source_type, OP_AND, orig, value_pseudo(~mask));
963 store = add_binary_op(ep, ad->source_type, OP_OR, orig, store);
964 }
965 add_store(ep, ad, store);
966 return value;
967 }
968
969 static pseudo_t add_binary_op(struct entrypoint *ep, struct symbol *ctype, int op, pseudo_t left, pseudo_t right)
970 {
971 struct instruction *insn = alloc_typed_instruction(op, ctype);
972 pseudo_t target = alloc_pseudo(insn);
973 insn->target = target;
974 use_pseudo(insn, left, &insn->src1);
975 use_pseudo(insn, right, &insn->src2);
976 add_one_insn(ep, insn);
977 return target;
978 }
979
980 static pseudo_t add_setval(struct entrypoint *ep, struct symbol *ctype, struct expression *val)
981 {
982 struct instruction *insn = alloc_typed_instruction(OP_SETVAL, ctype);
983 pseudo_t target = alloc_pseudo(insn);
984 insn->target = target;
985 insn->val = val;
986 add_one_insn(ep, insn);
987 return target;
988 }
989
990 static pseudo_t add_symbol_address(struct entrypoint *ep, struct symbol *sym)
991 {
992 struct instruction *insn = alloc_instruction(OP_SYMADDR, bits_in_pointer);
993 pseudo_t target = alloc_pseudo(insn);
994
995 insn->target = target;
996 use_pseudo(insn, symbol_pseudo(ep, sym), &insn->symbol);
997 add_one_insn(ep, insn);
998 return target;
999 }
1000
1001 static pseudo_t linearize_load_gen(struct entrypoint *ep, struct access_data *ad)
1002 {
1003 pseudo_t new = add_load(ep, ad);
1004
1005 if (ad->bit_offset) {
1006 pseudo_t shift = value_pseudo(ad->bit_offset);
1007 pseudo_t newval = add_binary_op(ep, ad->source_type, OP_LSR, new, shift);
1008 new = newval;
1009 }
1010 if (ad->bit_size != type_size(ad->source_type))
1011 new = cast_pseudo(ep, new, ad->source_type, ad->result_type);
1012 return new;
1013 }
1014
1015 static pseudo_t linearize_access(struct entrypoint *ep, struct expression *expr)
1016 {
1017 struct access_data ad = { NULL, };
1018 pseudo_t value;
1019
1020 if (!linearize_address_gen(ep, expr, &ad))
1021 return VOID;
1022 value = linearize_load_gen(ep, &ad);
1023 finish_address_gen(ep, &ad);
1024 return value;
1025 }
1026
1027 /* FIXME: FP */
1028 static pseudo_t linearize_inc_dec(struct entrypoint *ep, struct expression *expr, int postop)
1029 {
1030 struct access_data ad = { NULL, };
1031 pseudo_t old, new, one;
1032 int op = expr->op == SPECIAL_INCREMENT ? OP_ADD : OP_SUB;
1033
1034 if (!linearize_address_gen(ep, expr->unop, &ad))
1035 return VOID;
1036
1037 old = linearize_load_gen(ep, &ad);
1038 one = value_pseudo(expr->op_value);
1039 new = add_binary_op(ep, expr->ctype, op, old, one);
1040 linearize_store_gen(ep, new, &ad);
1041 finish_address_gen(ep, &ad);
1042 return postop ? old : new;
1043 }
1044
1045 static pseudo_t add_uniop(struct entrypoint *ep, struct expression *expr, int op, pseudo_t src)
1046 {
1047 struct instruction *insn = alloc_typed_instruction(op, expr->ctype);
1048 pseudo_t new = alloc_pseudo(insn);
1049
1050 insn->target = new;
1051 use_pseudo(insn, src, &insn->src1);
1052 add_one_insn(ep, insn);
1053 return new;
1054 }
1055
1056 static pseudo_t linearize_slice(struct entrypoint *ep, struct expression *expr)
1057 {
1058 pseudo_t pre = linearize_expression(ep, expr->base);
1059 struct instruction *insn = alloc_typed_instruction(OP_SLICE, expr->ctype);
1060 pseudo_t new = alloc_pseudo(insn);
1061
1062 insn->target = new;
1063 insn->from = expr->r_bitpos;
1064 insn->len = expr->r_nrbits;
1065 use_pseudo(insn, pre, &insn->base);
1066 add_one_insn(ep, insn);
1067 return new;
1068 }
1069
1070 static pseudo_t linearize_regular_preop(struct entrypoint *ep, struct expression *expr)
1071 {
1072 pseudo_t pre = linearize_expression(ep, expr->unop);
1073 switch (expr->op) {
1074 case '+':
1075 return pre;
1076 case '!': {
1077 pseudo_t zero = value_pseudo(0);
1078 return add_binary_op(ep, expr->ctype, OP_SET_EQ, pre, zero);
1079 }
1080 case '~':
1081 return add_uniop(ep, expr, OP_NOT, pre);
1082 case '-':
1083 return add_uniop(ep, expr, OP_NEG, pre);
1084 }
1085 return VOID;
1086 }
1087
1088 static pseudo_t linearize_preop(struct entrypoint *ep, struct expression *expr)
1089 {
1090 /*
1091 * '*' is an lvalue access, and is fundamentally different
1092 * from an arithmetic operation. Maybe it should have an
1093 * expression type of its own..
1094 */
1095 if (expr->op == '*')
1096 return linearize_access(ep, expr);
1097 if (expr->op == SPECIAL_INCREMENT || expr->op == SPECIAL_DECREMENT)
1098 return linearize_inc_dec(ep, expr, 0);
1099 return linearize_regular_preop(ep, expr);
1100 }
1101
1102 static pseudo_t linearize_postop(struct entrypoint *ep, struct expression *expr)
1103 {
1104 return linearize_inc_dec(ep, expr, 1);
1105 }
1106
1107 /*
1108 * Casts to pointers are "less safe" than other casts, since
1109 * they imply type-unsafe accesses. "void *" is a special
1110 * case, since you can't access through it anyway without another
1111 * cast.
1112 */
1113 static struct instruction *alloc_cast_instruction(struct symbol *src, struct symbol *ctype)
1114 {
1115 int opcode = OP_CAST;
1116 struct symbol *base = ctype;
1117
1118 if (src->ctype.modifiers & MOD_SIGNED)
1119 opcode = OP_SCAST;
1120 if (base->type == SYM_NODE)
1121 base = base->ctype.base_type;
1122 if (base->type == SYM_PTR) {
1123 base = base->ctype.base_type;
1124 if (base != &void_ctype)
1125 opcode = OP_PTRCAST;
1126 } else if (base->ctype.base_type == &fp_type)
1127 opcode = OP_FPCAST;
1128 return alloc_typed_instruction(opcode, ctype);
1129 }
1130
1131 static pseudo_t cast_pseudo(struct entrypoint *ep, pseudo_t src, struct symbol *from, struct symbol *to)
1132 {
1133 pseudo_t result;
1134 struct instruction *insn;
1135
1136 if (src == VOID)
1137 return VOID;
1138 if (!from || !to)
1139 return VOID;
1140 if (from->bit_size < 0 || to->bit_size < 0)
1141 return VOID;
1142 insn = alloc_cast_instruction(from, to);
1143 result = alloc_pseudo(insn);
1144 insn->target = result;
1145 insn->orig_type = from;
1146 use_pseudo(insn, src, &insn->src);
1147 add_one_insn(ep, insn);
1148 return result;
1149 }
1150
1151 static int opcode_sign(int opcode, struct symbol *ctype)
1152 {
1153 if (ctype && (ctype->ctype.modifiers & MOD_SIGNED)) {
1154 switch(opcode) {
1155 case OP_MULU: case OP_DIVU: case OP_MODU: case OP_LSR:
1156 opcode++;
1157 }
1158 }
1159 return opcode;
1160 }
1161
1162 static pseudo_t linearize_assignment(struct entrypoint *ep, struct expression *expr)
1163 {
1164 struct access_data ad = { NULL, };
1165 struct expression *target = expr->left;
1166 struct expression *src = expr->right;
1167 struct symbol *ctype;
1168 pseudo_t value;
1169
1170 value = linearize_expression(ep, src);
1171 if (!target || !linearize_address_gen(ep, target, &ad))
1172 return value;
1173 if (expr->op != '=') {
1174 pseudo_t oldvalue = linearize_load_gen(ep, &ad);
1175 pseudo_t dst;
1176 static const int op_trans[] = {
1177 [SPECIAL_ADD_ASSIGN - SPECIAL_BASE] = OP_ADD,
1178 [SPECIAL_SUB_ASSIGN - SPECIAL_BASE] = OP_SUB,
1179 [SPECIAL_MUL_ASSIGN - SPECIAL_BASE] = OP_MULU,
1180 [SPECIAL_DIV_ASSIGN - SPECIAL_BASE] = OP_DIVU,
1181 [SPECIAL_MOD_ASSIGN - SPECIAL_BASE] = OP_MODU,
1182 [SPECIAL_SHL_ASSIGN - SPECIAL_BASE] = OP_SHL,
1183 [SPECIAL_SHR_ASSIGN - SPECIAL_BASE] = OP_LSR,
1184 [SPECIAL_AND_ASSIGN - SPECIAL_BASE] = OP_AND,
1185 [SPECIAL_OR_ASSIGN - SPECIAL_BASE] = OP_OR,
1186 [SPECIAL_XOR_ASSIGN - SPECIAL_BASE] = OP_XOR
1187 };
1188 int opcode;
1189
1190 if (!src)
1191 return VOID;
1192
1193 ctype = src->ctype;
1194 oldvalue = cast_pseudo(ep, oldvalue, target->ctype, ctype);
1195 opcode = opcode_sign(op_trans[expr->op - SPECIAL_BASE], ctype);
1196 dst = add_binary_op(ep, ctype, opcode, oldvalue, value);
1197 value = cast_pseudo(ep, dst, ctype, expr->ctype);
1198 }
1199 value = linearize_store_gen(ep, value, &ad);
1200 finish_address_gen(ep, &ad);
1201 return value;
1202 }
1203
1204 static pseudo_t linearize_call_expression(struct entrypoint *ep, struct expression *expr)
1205 {
1206 struct expression *arg, *fn;
1207 struct instruction *insn = alloc_typed_instruction(OP_CALL, expr->ctype);
1208 pseudo_t retval, call;
1209 struct ctype *ctype = NULL;
1210 struct symbol *fntype;
1211 struct context *context;
1212
1213 if (!expr->ctype) {
1214 warning(expr->pos, "call with no type!");
1215 return VOID;
1216 }
1217
1218 FOR_EACH_PTR(expr->args, arg) {
1219 pseudo_t new = linearize_expression(ep, arg);
1220 use_pseudo(insn, new, add_pseudo(&insn->arguments, new));
1221 } END_FOR_EACH_PTR(arg);
1222
1223 fn = expr->fn;
1224
1225 if (fn->ctype)
1226 ctype = &fn->ctype->ctype;
1227
1228 fntype = fn->ctype;
1229 if (fntype) {
1230 if (fntype->type == SYM_NODE)
1231 fntype = fntype->ctype.base_type;
1232 }
1233 insn->fntype = fntype;
1234
1235 if (fn->type == EXPR_PREOP) {
1236 if (fn->unop->type == EXPR_SYMBOL) {
1237 struct symbol *sym = fn->unop->symbol;
1238 if (sym->ctype.base_type->type == SYM_FN)
1239 fn = fn->unop;
1240 }
1241 }
1242 if (fn->type == EXPR_SYMBOL) {
1243 call = symbol_pseudo(ep, fn->symbol);
1244 } else {
1245 call = linearize_expression(ep, fn);
1246 }
1247 use_pseudo(insn, call, &insn->func);
1248 retval = VOID;
1249 if (expr->ctype != &void_ctype)
1250 retval = alloc_pseudo(insn);
1251 insn->target = retval;
1252 add_one_insn(ep, insn);
1253
1254 if (ctype) {
1255 FOR_EACH_PTR(ctype->contexts, context) {
1256 int in = context->in;
1257 int out = context->out;
1258 int check = 0;
1259 int context_diff;
1260 if (in < 0) {
1261 check = 1;
1262 in = 0;
1263 }
1264 if (out < 0) {
1265 check = 0;
1266 out = 0;
1267 }
1268 context_diff = out - in;
1269 if (check || context_diff) {
1270 insn = alloc_instruction(OP_CONTEXT, 0);
1271 insn->increment = context_diff;
1272 insn->check = check;
1273 insn->context_expr = context->context;
1274 add_one_insn(ep, insn);
1275 }
1276 } END_FOR_EACH_PTR(context);
1277 }
1278
1279 return retval;
1280 }
1281
1282 static pseudo_t linearize_binop(struct entrypoint *ep, struct expression *expr)
1283 {
1284 pseudo_t src1, src2, dst;
1285 static const int opcode[] = {
1286 ['+'] = OP_ADD, ['-'] = OP_SUB,
1287 ['*'] = OP_MULU, ['/'] = OP_DIVU,
1288 ['%'] = OP_MODU, ['&'] = OP_AND,
1289 ['|'] = OP_OR, ['^'] = OP_XOR,
1290 [SPECIAL_LEFTSHIFT] = OP_SHL,
1291 [SPECIAL_RIGHTSHIFT] = OP_LSR,
1292 [SPECIAL_LOGICAL_AND] = OP_AND_BOOL,
1293 [SPECIAL_LOGICAL_OR] = OP_OR_BOOL,
1294 };
1295 int op;
1296
1297 src1 = linearize_expression(ep, expr->left);
1298 src2 = linearize_expression(ep, expr->right);
1299 op = opcode_sign(opcode[expr->op], expr->ctype);
1300 dst = add_binary_op(ep, expr->ctype, op, src1, src2);
1301 return dst;
1302 }
1303
1304 static pseudo_t linearize_logical_branch(struct entrypoint *ep, struct expression *expr, struct basic_block *bb_true, struct basic_block *bb_false);
1305
1306 pseudo_t linearize_cond_branch(struct entrypoint *ep, struct expression *expr, struct basic_block *bb_true, struct basic_block *bb_false);
1307
1308 static pseudo_t linearize_select(struct entrypoint *ep, struct expression *expr)
1309 {
1310 pseudo_t cond, true, false, res;
1311 struct instruction *insn;
1312
1313 true = linearize_expression(ep, expr->cond_true);
1314 false = linearize_expression(ep, expr->cond_false);
1315 cond = linearize_expression(ep, expr->conditional);
1316
1317 insn = alloc_typed_instruction(OP_SEL, expr->ctype);
1318 if (!expr->cond_true)
1319 true = cond;
1320 use_pseudo(insn, cond, &insn->src1);
1321 use_pseudo(insn, true, &insn->src2);
1322 use_pseudo(insn, false, &insn->src3);
1323
1324 res = alloc_pseudo(insn);
1325 insn->target = res;
1326 add_one_insn(ep, insn);
1327 return res;
1328 }
1329
1330 static pseudo_t add_join_conditional(struct entrypoint *ep, struct expression *expr,
1331 pseudo_t phi1, pseudo_t phi2)
1332 {
1333 pseudo_t target;
1334 struct instruction *phi_node;
1335
1336 if (phi1 == VOID)
1337 return phi2;
1338 if (phi2 == VOID)
1339 return phi1;
1340
1341 phi_node = alloc_typed_instruction(OP_PHI, expr->ctype);
1342 use_pseudo(phi_node, phi1, add_pseudo(&phi_node->phi_list, phi1));
1343 use_pseudo(phi_node, phi2, add_pseudo(&phi_node->phi_list, phi2));
1344 phi_node->target = target = alloc_pseudo(phi_node);
1345 add_one_insn(ep, phi_node);
1346 return target;
1347 }
1348
1349 static pseudo_t linearize_short_conditional(struct entrypoint *ep, struct expression *expr,
1350 struct expression *cond,
1351 struct expression *expr_false)
1352 {
1353 pseudo_t src1, src2;
1354 struct basic_block *bb_false;
1355 struct basic_block *merge = alloc_basic_block(ep, expr->pos);
1356 pseudo_t phi1, phi2;
1357 int size = type_size(expr->ctype);
1358
1359 if (!expr_false || !ep->active)
1360 return VOID;
1361
1362 bb_false = alloc_basic_block(ep, expr_false->pos);
1363 src1 = linearize_expression(ep, cond);
1364 phi1 = alloc_phi(ep->active, src1, size);
1365 add_branch(ep, expr, src1, merge, bb_false);
1366
1367 set_activeblock(ep, bb_false);
1368 src2 = linearize_expression(ep, expr_false);
1369 phi2 = alloc_phi(ep->active, src2, size);
1370 set_activeblock(ep, merge);
1371
1372 return add_join_conditional(ep, expr, phi1, phi2);
1373 }
1374
1375 static pseudo_t linearize_conditional(struct entrypoint *ep, struct expression *expr,
1376 struct expression *cond,
1377 struct expression *expr_true,
1378 struct expression *expr_false)
1379 {
1380 pseudo_t src1, src2;
1381 pseudo_t phi1, phi2;
1382 struct basic_block *bb_true, *bb_false, *merge;
1383 int size = type_size(expr->ctype);
1384
1385 if (!cond || !expr_true || !expr_false || !ep->active)
1386 return VOID;
1387 bb_true = alloc_basic_block(ep, expr_true->pos);
1388 bb_false = alloc_basic_block(ep, expr_false->pos);
1389 merge = alloc_basic_block(ep, expr->pos);
1390
1391 linearize_cond_branch(ep, cond, bb_true, bb_false);
1392
1393 set_activeblock(ep, bb_true);
1394 src1 = linearize_expression(ep, expr_true);
1395 phi1 = alloc_phi(ep->active, src1, size);
1396 add_goto(ep, merge);
1397
1398 set_activeblock(ep, bb_false);
1399 src2 = linearize_expression(ep, expr_false);
1400 phi2 = alloc_phi(ep->active, src2, size);
1401 set_activeblock(ep, merge);
1402
1403 return add_join_conditional(ep, expr, phi1, phi2);
1404 }
1405
1406 static pseudo_t linearize_logical(struct entrypoint *ep, struct expression *expr)
1407 {
1408 struct expression *shortcut;
1409
1410 shortcut = alloc_const_expression(expr->pos, expr->op == SPECIAL_LOGICAL_OR);
1411 shortcut->ctype = expr->ctype;
1412 if (expr->op == SPECIAL_LOGICAL_OR)
1413 return linearize_conditional(ep, expr, expr->left, shortcut, expr->right);
1414 return linearize_conditional(ep, expr, expr->left, expr->right, shortcut);
1415 }
1416
1417 static pseudo_t linearize_compare(struct entrypoint *ep, struct expression *expr)
1418 {
1419 static const int cmpop[] = {
1420 ['>'] = OP_SET_GT, ['<'] = OP_SET_LT,
1421 [SPECIAL_EQUAL] = OP_SET_EQ,
1422 [SPECIAL_NOTEQUAL] = OP_SET_NE,
1423 [SPECIAL_GTE] = OP_SET_GE,
1424 [SPECIAL_LTE] = OP_SET_LE,
1425 [SPECIAL_UNSIGNED_LT] = OP_SET_B,
1426 [SPECIAL_UNSIGNED_GT] = OP_SET_A,
1427 [SPECIAL_UNSIGNED_LTE] = OP_SET_BE,
1428 [SPECIAL_UNSIGNED_GTE] = OP_SET_AE,
1429 };
1430
1431 pseudo_t src1 = linearize_expression(ep, expr->left);
1432 pseudo_t src2 = linearize_expression(ep, expr->right);
1433 pseudo_t dst = add_binary_op(ep, expr->ctype, cmpop[expr->op], src1, src2);
1434 return dst;
1435 }
1436
1437
1438 pseudo_t linearize_cond_branch(struct entrypoint *ep, struct expression *expr, struct basic_block *bb_true, struct basic_block *bb_false)
1439 {
1440 pseudo_t cond;
1441
1442 if (!expr || !bb_reachable(ep->active))
1443 return VOID;
1444
1445 switch (expr->type) {
1446
1447 case EXPR_STRING:
1448 case EXPR_VALUE:
1449 add_goto(ep, expr->value ? bb_true : bb_false);
1450 return VOID;
1451
1452 case EXPR_FVALUE:
1453 add_goto(ep, expr->fvalue ? bb_true : bb_false);
1454 return VOID;
1455
1456 case EXPR_LOGICAL:
1457 linearize_logical_branch(ep, expr, bb_true, bb_false);
1458 return VOID;
1459
1460 case EXPR_COMPARE:
1461 cond = linearize_compare(ep, expr);
1462 add_branch(ep, expr, cond, bb_true, bb_false);
1463 break;
1464
1465 case EXPR_PREOP:
1466 if (expr->op == '!')
1467 return linearize_cond_branch(ep, expr->unop, bb_false, bb_true);
1468 /* fall through */
1469 default: {
1470 cond = linearize_expression(ep, expr);
1471 add_branch(ep, expr, cond, bb_true, bb_false);
1472
1473 return VOID;
1474 }
1475 }
1476 return VOID;
1477 }
1478
1479
1480
1481 static pseudo_t linearize_logical_branch(struct entrypoint *ep, struct expression *expr, struct basic_block *bb_true, struct basic_block *bb_false)
1482 {
1483 struct basic_block *next = alloc_basic_block(ep, expr->pos);
1484
1485 if (expr->op == SPECIAL_LOGICAL_OR)
1486 linearize_cond_branch(ep, expr->left, bb_true, next);
1487 else
1488 linearize_cond_branch(ep, expr->left, next, bb_false);
1489 set_activeblock(ep, next);
1490 linearize_cond_branch(ep, expr->right, bb_true, bb_false);
1491 return VOID;
1492 }
1493
1494 static pseudo_t linearize_cast(struct entrypoint *ep, struct expression *expr)
1495 {
1496 pseudo_t src;
1497 struct expression *orig = expr->cast_expression;
1498
1499 if (!orig)
1500 return VOID;
1501
1502 src = linearize_expression(ep, orig);
1503 return cast_pseudo(ep, src, orig->ctype, expr->ctype);
1504 }
1505
1506 static pseudo_t linearize_position(struct entrypoint *ep, struct expression *pos, struct access_data *ad)
1507 {
1508 struct expression *init_expr = pos->init_expr;
1509
1510 ad->offset = pos->init_offset;
1511 ad->source_type = base_type(init_expr->ctype);
1512 ad->result_type = init_expr->ctype;
1513 return linearize_initializer(ep, init_expr, ad);
1514 }
1515
1516 static pseudo_t linearize_initializer(struct entrypoint *ep, struct expression *initializer, struct access_data *ad)
1517 {
1518 switch (initializer->type) {
1519 case EXPR_INITIALIZER: {
1520 struct expression *expr;
1521 FOR_EACH_PTR(initializer->expr_list, expr) {
1522 linearize_initializer(ep, expr, ad);
1523 } END_FOR_EACH_PTR(expr);
1524 break;
1525 }
1526 case EXPR_POS:
1527 linearize_position(ep, initializer, ad);
1528 break;
1529 default: {
1530 pseudo_t value = linearize_expression(ep, initializer);
1531 ad->source_type = base_type(initializer->ctype);
1532 ad->result_type = initializer->ctype;
1533 linearize_store_gen(ep, value, ad);
1534 return value;
1535 }
1536 }
1537
1538 return VOID;
1539 }
1540
1541 static void linearize_argument(struct entrypoint *ep, struct symbol *arg, int nr)
1542 {
1543 struct access_data ad = { NULL, };
1544
1545 ad.source_type = arg;
1546 ad.result_type = arg;
1547 ad.address = symbol_pseudo(ep, arg);
1548 linearize_store_gen(ep, argument_pseudo(ep, nr), &ad);
1549 finish_address_gen(ep, &ad);
1550 }
1551
1552 pseudo_t linearize_expression(struct entrypoint *ep, struct expression *expr)
1553 {
1554 if (!expr)
1555 return VOID;
1556
1557 current_pos = expr->pos;
1558 switch (expr->type) {
1559 case EXPR_SYMBOL:
1560 linearize_one_symbol(ep, expr->symbol);
1561 return add_symbol_address(ep, expr->symbol);
1562
1563 case EXPR_VALUE:
1564 return value_pseudo(expr->value);
1565
1566 case EXPR_STRING: case EXPR_FVALUE: case EXPR_LABEL:
1567 return add_setval(ep, expr->ctype, expr);
1568
1569 case EXPR_STATEMENT:
1570 return linearize_statement(ep, expr->statement);
1571
1572 case EXPR_CALL:
1573 return linearize_call_expression(ep, expr);
1574
1575 case EXPR_BINOP:
1576 return linearize_binop(ep, expr);
1577
1578 case EXPR_LOGICAL:
1579 return linearize_logical(ep, expr);
1580
1581 case EXPR_COMPARE:
1582 return linearize_compare(ep, expr);
1583
1584 case EXPR_SELECT:
1585 return linearize_select(ep, expr);
1586
1587 case EXPR_CONDITIONAL:
1588 if (!expr->cond_true)
1589 return linearize_short_conditional(ep, expr, expr->conditional, expr->cond_false);
1590
1591 return linearize_conditional(ep, expr, expr->conditional,
1592 expr->cond_true, expr->cond_false);
1593
1594 case EXPR_COMMA:
1595 linearize_expression(ep, expr->left);
1596 return linearize_expression(ep, expr->right);
1597
1598 case EXPR_ASSIGNMENT:
1599 return linearize_assignment(ep, expr);
1600
1601 case EXPR_PREOP:
1602 return linearize_preop(ep, expr);
1603
1604 case EXPR_POSTOP:
1605 return linearize_postop(ep, expr);
1606
1607 case EXPR_CAST:
1608 case EXPR_FORCE_CAST:
1609 case EXPR_IMPLIED_CAST:
1610 return linearize_cast(ep, expr);
1611
1612 case EXPR_SLICE:
1613 return linearize_slice(ep, expr);
1614
1615 case EXPR_INITIALIZER:
1616 case EXPR_POS:
1617 warning(expr->pos, "unexpected initializer expression (%d %d)", expr->type, expr->op);
1618 return VOID;
1619 default:
1620 warning(expr->pos, "unknown expression (%d %d)", expr->type, expr->op);
1621 return VOID;
1622 }
1623 return VOID;
1624 }
1625
1626 static pseudo_t linearize_one_symbol(struct entrypoint *ep, struct symbol *sym)
1627 {
1628 struct access_data ad = { NULL, };
1629 pseudo_t value;
1630
1631 if (!sym || !sym->initializer || sym->initialized)
1632 return VOID;
1633
1634 /* We need to output these puppies some day too.. */
1635 if (sym->ctype.modifiers & (MOD_STATIC | MOD_TOPLEVEL))
1636 return VOID;
1637
1638 sym->initialized = 1;
1639 ad.address = symbol_pseudo(ep, sym);
1640 value = linearize_initializer(ep, sym->initializer, &ad);
1641 finish_address_gen(ep, &ad);
1642 return value;
1643 }
1644
1645 static pseudo_t linearize_compound_statement(struct entrypoint *ep, struct statement *stmt)
1646 {
1647 pseudo_t pseudo;
1648 struct statement *s;
1649 struct symbol *ret = stmt->ret;
1650
1651 pseudo = VOID;
1652 FOR_EACH_PTR(stmt->stmts, s) {
1653 pseudo = linearize_statement(ep, s);
1654 } END_FOR_EACH_PTR(s);
1655
1656 if (ret) {
1657 struct basic_block *bb = add_label(ep, ret);
1658 struct instruction *phi_node = first_instruction(bb->insns);
1659
1660 if (!phi_node)
1661 return pseudo;
1662
1663 if (pseudo_list_size(phi_node->phi_list)==1) {
1664 pseudo = first_pseudo(phi_node->phi_list);
1665 assert(pseudo->type == PSEUDO_PHI);
1666 return pseudo->def->src1;
1667 }
1668 return phi_node->target;
1669 }
1670
1671 return pseudo;
1672 }
1673
1674 static pseudo_t linearize_inlined_call(struct entrypoint *ep, struct statement *stmt)
1675 {
1676 struct instruction *insn = alloc_instruction(OP_INLINED_CALL, 0);
1677 struct statement *args = stmt->args;
1678 struct basic_block *bb;
1679 pseudo_t pseudo;
1680
1681 if (args) {
1682 struct symbol *sym;
1683
1684 concat_symbol_list(args->declaration, &ep->syms);
1685 FOR_EACH_PTR(args->declaration, sym) {
1686 pseudo_t value = linearize_one_symbol(ep, sym);
1687 use_pseudo(insn, value, add_pseudo(&insn->arguments, value));
1688 } END_FOR_EACH_PTR(sym);
1689 }
1690
1691 insn->target = pseudo = linearize_compound_statement(ep, stmt);
1692 use_pseudo(insn, symbol_pseudo(ep, stmt->inline_fn), &insn->func);
1693 bb = ep->active;
1694 if (bb && !bb->insns)
1695 bb->pos = stmt->pos;
1696 add_one_insn(ep, insn);
1697 return pseudo;
1698 }
1699
1700 static pseudo_t linearize_context(struct entrypoint *ep, struct statement *stmt)
1701 {
1702 struct instruction *insn = alloc_instruction(OP_CONTEXT, 0);
1703 struct expression *expr = stmt->expression;
1704 int value = 0;
1705
1706 if (expr->type == EXPR_VALUE)
1707 value = expr->value;
1708
1709 insn->increment = value;
1710 insn->context_expr = stmt->context;
1711 add_one_insn(ep, insn);
1712 return VOID;
1713 }
1714
1715 static pseudo_t linearize_range(struct entrypoint *ep, struct statement *stmt)
1716 {
1717 struct instruction *insn = alloc_instruction(OP_RANGE, 0);
1718
1719 use_pseudo(insn, linearize_expression(ep, stmt->range_expression), &insn->src1);
1720 use_pseudo(insn, linearize_expression(ep, stmt->range_low), &insn->src2);
1721 use_pseudo(insn, linearize_expression(ep, stmt->range_high), &insn->src3);
1722 add_one_insn(ep, insn);
1723 return VOID;
1724 }
1725
1726 ALLOCATOR(asm_rules, "asm rules");
1727 ALLOCATOR(asm_constraint, "asm constraints");
1728
1729 static void add_asm_input(struct entrypoint *ep, struct instruction *insn, struct expression *expr,
1730 const char *constraint, const struct ident *ident)
1731 {
1732 pseudo_t pseudo = linearize_expression(ep, expr);
1733 struct asm_constraint *rule = __alloc_asm_constraint(0);
1734
1735 rule->ident = ident;
1736 rule->constraint = constraint;
1737 use_pseudo(insn, pseudo, &rule->pseudo);
1738 add_ptr_list(&insn->asm_rules->inputs, rule);
1739 }
1740
1741 static void add_asm_output(struct entrypoint *ep, struct instruction *insn, struct expression *expr,
1742 const char *constraint, const struct ident *ident)
1743 {
1744 struct access_data ad = { NULL, };
1745 pseudo_t pseudo = alloc_pseudo(insn);
1746 struct asm_constraint *rule;
1747
1748 if (!expr || !linearize_address_gen(ep, expr, &ad))
1749 return;
1750 linearize_store_gen(ep, pseudo, &ad);
1751 finish_address_gen(ep, &ad);
1752 rule = __alloc_asm_constraint(0);
1753 rule->ident = ident;
1754 rule->constraint = constraint;
1755 use_pseudo(insn, pseudo, &rule->pseudo);
1756 add_ptr_list(&insn->asm_rules->outputs, rule);
1757 }
1758
1759 static pseudo_t linearize_asm_statement(struct entrypoint *ep, struct statement *stmt)
1760 {
1761 int state;
1762 struct expression *expr;
1763 struct instruction *insn;
1764 struct asm_rules *rules;
1765 const char *constraint;
1766 struct ident *ident;
1767
1768 insn = alloc_instruction(OP_ASM, 0);
1769 expr = stmt->asm_string;
1770 if (!expr || expr->type != EXPR_STRING) {
1771 warning(stmt->pos, "expected string in inline asm");
1772 return VOID;
1773 }
1774 insn->string = expr->string->data;
1775
1776 rules = __alloc_asm_rules(0);
1777 insn->asm_rules = rules;
1778
1779 /* Gather the inputs.. */
1780 state = 0;
1781 ident = NULL;
1782 constraint = NULL;
1783 FOR_EACH_PTR(stmt->asm_inputs, expr) {
1784 switch (state) {
1785 case 0: /* Identifier */
1786 state = 1;
1787 ident = (struct ident *)expr;
1788 continue;
1789
1790 case 1: /* Constraint */
1791 state = 2;
1792 constraint = expr ? expr->string->data : "";
1793 continue;
1794
1795 case 2: /* Expression */
1796 state = 0;
1797 add_asm_input(ep, insn, expr, constraint, ident);
1798 }
1799 } END_FOR_EACH_PTR(expr);
1800
1801 add_one_insn(ep, insn);
1802
1803 /* Assign the outputs */
1804 state = 0;
1805 ident = NULL;
1806 constraint = NULL;
1807 FOR_EACH_PTR(stmt->asm_outputs, expr) {
1808 switch (state) {
1809 case 0: /* Identifier */
1810 state = 1;
1811 ident = (struct ident *)expr;
1812 continue;
1813
1814 case 1: /* Constraint */
1815 state = 2;
1816 constraint = expr ? expr->string->data : "";
1817 continue;
1818
1819 case 2:
1820 state = 0;
1821 add_asm_output(ep, insn, expr, constraint, ident);
1822 }
1823 } END_FOR_EACH_PTR(expr);
1824
1825 return VOID;
1826 }
1827
1828 static int multijmp_cmp(const void *_a, const void *_b)
1829 {
1830 const struct multijmp *a = _a;
1831 const struct multijmp *b = _b;
1832
1833 // "default" case?
1834 if (a->begin > a->end) {
1835 if (b->begin > b->end)
1836 return 0;
1837 return 1;
1838 }
1839 if (b->begin > b->end)
1840 return -1;
1841 if (a->begin == b->begin) {
1842 if (a->end == b->end)
1843 return 0;
1844 return (a->end < b->end) ? -1 : 1;
1845 }
1846 return a->begin < b->begin ? -1 : 1;
1847 }
1848
1849 static void sort_switch_cases(struct instruction *insn)
1850 {
1851 sort_list((struct ptr_list **)&insn->multijmp_list, multijmp_cmp);
1852 }
1853
1854 static pseudo_t linearize_declaration(struct entrypoint *ep, struct statement *stmt)
1855 {
1856 struct symbol *sym;
1857
1858 concat_symbol_list(stmt->declaration, &ep->syms);
1859
1860 FOR_EACH_PTR(stmt->declaration, sym) {
1861 linearize_one_symbol(ep, sym);
1862 } END_FOR_EACH_PTR(sym);
1863 return VOID;
1864 }
1865
1866 static pseudo_t linearize_return(struct entrypoint *ep, struct statement *stmt)
1867 {
1868 struct expression *expr = stmt->expression;
1869 struct basic_block *bb_return = get_bound_block(ep, stmt->ret_target);
1870 struct basic_block *active;
1871 pseudo_t src = linearize_expression(ep, expr);
1872 active = ep->active;
1873 if (active && src != VOID) {
1874 struct instruction *phi_node = first_instruction(bb_return->insns);
1875 pseudo_t phi;
1876 if (!phi_node) {
1877 phi_node = alloc_typed_instruction(OP_PHI, expr->ctype);
1878 phi_node->target = alloc_pseudo(phi_node);
1879 phi_node->bb = bb_return;
1880 add_instruction(&bb_return->insns, phi_node);
1881 }
1882 phi = alloc_phi(active, src, type_size(expr->ctype));
1883 phi->ident = &return_ident;
1884 use_pseudo(phi_node, phi, add_pseudo(&phi_node->phi_list, phi));
1885 }
1886 add_goto(ep, bb_return);
1887 return VOID;
1888 }
1889
1890 static pseudo_t linearize_switch(struct entrypoint *ep, struct statement *stmt)
1891 {
1892 struct symbol *sym;
1893 struct instruction *switch_ins;
1894 struct basic_block *switch_end = alloc_basic_block(ep, stmt->pos);
1895 struct basic_block *active, *default_case;
1896 struct multijmp *jmp;
1897 pseudo_t pseudo;
1898
1899 pseudo = linearize_expression(ep, stmt->switch_expression);
1900
1901 active = ep->active;
1902 if (!bb_reachable(active))
1903 return VOID;
1904
1905 switch_ins = alloc_instruction(OP_SWITCH, 0);
1906 use_pseudo(switch_ins, pseudo, &switch_ins->cond);
1907 add_one_insn(ep, switch_ins);
1908 finish_block(ep);
1909
1910 default_case = NULL;
1911 FOR_EACH_PTR(stmt->switch_case->symbol_list, sym) {
1912 struct statement *case_stmt = sym->stmt;
1913 struct basic_block *bb_case = get_bound_block(ep, sym);
1914
1915 if (!case_stmt->case_expression) {
1916 default_case = bb_case;
1917 continue;
1918 } else {
1919 int begin, end;
1920
1921 begin = end = case_stmt->case_expression->value;
1922 if (case_stmt->case_to)
1923 end = case_stmt->case_to->value;
1924 if (begin > end)
1925 jmp = alloc_multijmp(bb_case, end, begin);
1926 else
1927 jmp = alloc_multijmp(bb_case, begin, end);
1928
1929 }
1930 add_multijmp(&switch_ins->multijmp_list, jmp);
1931 add_bb(&bb_case->parents, active);
1932 add_bb(&active->children, bb_case);
1933 } END_FOR_EACH_PTR(sym);
1934
1935 bind_label(stmt->switch_break, switch_end, stmt->pos);
1936
1937 /* And linearize the actual statement */
1938 linearize_statement(ep, stmt->switch_statement);
1939 set_activeblock(ep, switch_end);
1940
1941 if (!default_case)
1942 default_case = switch_end;
1943
1944 jmp = alloc_multijmp(default_case, 1, 0);
1945 add_multijmp(&switch_ins->multijmp_list, jmp);
1946 add_bb(&default_case->parents, active);
1947 add_bb(&active->children, default_case);
1948 sort_switch_cases(switch_ins);
1949
1950 return VOID;
1951 }
1952
1953 static pseudo_t linearize_iterator(struct entrypoint *ep, struct statement *stmt)
1954 {
1955 struct statement *pre_statement = stmt->iterator_pre_statement;
1956 struct expression *pre_condition = stmt->iterator_pre_condition;
1957 struct statement *statement = stmt->iterator_statement;
1958 struct statement *post_statement = stmt->iterator_post_statement;
1959 struct expression *post_condition = stmt->iterator_post_condition;
1960 struct basic_block *loop_top, *loop_body, *loop_continue, *loop_end;
1961 struct symbol *sym;
1962
1963 FOR_EACH_PTR(stmt->iterator_syms, sym) {
1964 linearize_one_symbol(ep, sym);
1965 } END_FOR_EACH_PTR(sym);
1966 concat_symbol_list(stmt->iterator_syms, &ep->syms);
1967 linearize_statement(ep, pre_statement);
1968
1969 loop_body = loop_top = alloc_basic_block(ep, stmt->pos);
1970 loop_continue = alloc_basic_block(ep, stmt->pos);
1971 loop_end = alloc_basic_block(ep, stmt->pos);
1972
1973 /* An empty post-condition means that it's the same as the pre-condition */
1974 if (!post_condition) {
1975 loop_top = alloc_basic_block(ep, stmt->pos);
1976 set_activeblock(ep, loop_top);
1977 }
1978
1979 if (pre_condition)
1980 linearize_cond_branch(ep, pre_condition, loop_body, loop_end);
1981
1982 bind_label(stmt->iterator_continue, loop_continue, stmt->pos);
1983 bind_label(stmt->iterator_break, loop_end, stmt->pos);
1984
1985 set_activeblock(ep, loop_body);
1986 linearize_statement(ep, statement);
1987 add_goto(ep, loop_continue);
1988
1989 set_activeblock(ep, loop_continue);
1990 linearize_statement(ep, post_statement);
1991 if (!post_condition)
1992 add_goto(ep, loop_top);
1993 else
1994 linearize_cond_branch(ep, post_condition, loop_top, loop_end);
1995 set_activeblock(ep, loop_end);
1996
1997 return VOID;
1998 }
1999
2000 pseudo_t linearize_statement(struct entrypoint *ep, struct statement *stmt)
2001 {
2002 struct basic_block *bb;
2003
2004 if (!stmt)
2005 return VOID;
2006
2007 bb = ep->active;
2008 if (bb && !bb->insns)
2009 bb->pos = stmt->pos;
2010 current_pos = stmt->pos;
2011
2012 switch (stmt->type) {
2013 case STMT_NONE:
2014 break;
2015
2016 case STMT_DECLARATION:
2017 return linearize_declaration(ep, stmt);
2018
2019 case STMT_CONTEXT:
2020 return linearize_context(ep, stmt);
2021
2022 case STMT_RANGE:
2023 return linearize_range(ep, stmt);
2024
2025 case STMT_EXPRESSION:
2026 return linearize_expression(ep, stmt->expression);
2027
2028 case STMT_ASM:
2029 return linearize_asm_statement(ep, stmt);
2030
2031 case STMT_RETURN:
2032 return linearize_return(ep, stmt);
2033
2034 case STMT_CASE: {
2035 add_label(ep, stmt->case_label);
2036 linearize_statement(ep, stmt->case_statement);
2037 break;
2038 }
2039
2040 case STMT_LABEL: {
2041 struct symbol *label = stmt->label_identifier;
2042
2043 if (label->used) {
2044 add_label(ep, label);
2045 }
2046 return linearize_statement(ep, stmt->label_statement);
2047 }
2048
2049 case STMT_GOTO: {
2050 struct symbol *sym;
2051 struct expression *expr;
2052 struct instruction *goto_ins;
2053 struct basic_block *active;
2054 pseudo_t pseudo;
2055
2056 active = ep->active;
2057 if (!bb_reachable(active))
2058 break;
2059
2060 if (stmt->goto_label) {
2061 add_goto(ep, get_bound_block(ep, stmt->goto_label));
2062 break;
2063 }
2064
2065 expr = stmt->goto_expression;
2066 if (!expr)
2067 break;
2068
2069 /* This can happen as part of simplification */
2070 if (expr->type == EXPR_LABEL) {
2071 add_goto(ep, get_bound_block(ep, expr->label_symbol));
2072 break;
2073 }
2074
2075 pseudo = linearize_expression(ep, expr);
2076 goto_ins = alloc_instruction(OP_COMPUTEDGOTO, 0);
2077 use_pseudo(goto_ins, pseudo, &goto_ins->target);
2078 add_one_insn(ep, goto_ins);
2079
2080 FOR_EACH_PTR(stmt->target_list, sym) {
2081 struct basic_block *bb_computed = get_bound_block(ep, sym);
2082 struct multijmp *jmp = alloc_multijmp(bb_computed, 1, 0);
2083 add_multijmp(&goto_ins->multijmp_list, jmp);
2084 add_bb(&bb_computed->parents, ep->active);
2085 add_bb(&active->children, bb_computed);
2086 } END_FOR_EACH_PTR(sym);
2087
2088 finish_block(ep);
2089 break;
2090 }
2091
2092 case STMT_COMPOUND:
2093 if (stmt->inline_fn)
2094 return linearize_inlined_call(ep, stmt);
2095 return linearize_compound_statement(ep, stmt);
2096
2097 /*
2098 * This could take 'likely/unlikely' into account, and
2099 * switch the arms around appropriately..
2100 */
2101 case STMT_IF: {
2102 struct basic_block *bb_true, *bb_false, *endif;
2103 struct expression *cond = stmt->if_conditional;
2104
2105 bb_true = alloc_basic_block(ep, stmt->pos);
2106 bb_false = endif = alloc_basic_block(ep, stmt->pos);
2107
2108 linearize_cond_branch(ep, cond, bb_true, bb_false);
2109
2110 set_activeblock(ep, bb_true);
2111 linearize_statement(ep, stmt->if_true);
2112
2113 if (stmt->if_false) {
2114 endif = alloc_basic_block(ep, stmt->pos);
2115 add_goto(ep, endif);
2116 set_activeblock(ep, bb_false);
2117 linearize_statement(ep, stmt->if_false);
2118 }
2119 set_activeblock(ep, endif);
2120 break;
2121 }
2122
2123 case STMT_SWITCH:
2124 return linearize_switch(ep, stmt);
2125
2126 case STMT_ITERATOR:
2127 return linearize_iterator(ep, stmt);
2128
2129 default:
2130 break;
2131 }
2132 return VOID;
2133 }
2134
2135 static struct entrypoint *linearize_fn(struct symbol *sym, struct symbol *base_type)
2136 {
2137 struct entrypoint *ep;
2138 struct basic_block *bb;
2139 struct symbol *arg;
2140 struct instruction *entry;
2141 pseudo_t result;
2142 int i;
2143
2144 if (!base_type->stmt)
2145 return NULL;
2146
2147 ep = alloc_entrypoint();
2148 bb = alloc_basic_block(ep, sym->pos);
2149
2150 ep->name = sym;
2151 sym->ep = ep;
2152 set_activeblock(ep, bb);
2153
2154 entry = alloc_instruction(OP_ENTRY, 0);
2155 add_one_insn(ep, entry);
2156 ep->entry = entry;
2157
2158 concat_symbol_list(base_type->arguments, &ep->syms);
2159
2160 /* FIXME!! We should do something else about varargs.. */
2161 i = 0;
2162 FOR_EACH_PTR(base_type->arguments, arg) {
2163 linearize_argument(ep, arg, ++i);
2164 } END_FOR_EACH_PTR(arg);
2165
2166 result = linearize_statement(ep, base_type->stmt);
2167 if (bb_reachable(ep->active) && !bb_terminated(ep->active)) {
2168 struct symbol *ret_type = base_type->ctype.base_type;
2169 struct instruction *insn = alloc_typed_instruction(OP_RET, ret_type);
2170
2171 if (type_size(ret_type) > 0)
2172 use_pseudo(insn, result, &insn->src);
2173 add_one_insn(ep, insn);
2174 }
2175
2176 /*
2177 * Do trivial flow simplification - branches to
2178 * branches, kill dead basicblocks etc
2179 */
2180 kill_unreachable_bbs(ep);
2181
2182 /*
2183 * Turn symbols into pseudos
2184 */
2185 simplify_symbol_usage(ep);
2186
2187 repeat:
2188 /*
2189 * Remove trivial instructions, and try to CSE
2190 * the rest.
2191 */
2192 do {
2193 cleanup_and_cse(ep);
2194 pack_basic_blocks(ep);
2195 } while (repeat_phase & REPEAT_CSE);
2196
2197 kill_unreachable_bbs(ep);
2198 vrfy_flow(ep);
2199
2200 /* Cleanup */
2201 clear_symbol_pseudos(ep);
2202
2203 /* And track pseudo register usage */
2204 track_pseudo_liveness(ep);
2205
2206 /*
2207 * Some flow optimizations can only effectively
2208 * be done when we've done liveness analysis. But
2209 * if they trigger, we need to start all over
2210 * again
2211 */
2212 if (simplify_flow(ep)) {
2213 clear_liveness(ep);
2214 goto repeat;
2215 }
2216
2217 /* Finally, add deathnotes to pseudos now that we have them */
2218 if (dbg_dead)
2219 track_pseudo_death(ep);
2220
2221 return ep;
2222 }
2223
2224 struct entrypoint *linearize_symbol(struct symbol *sym)
2225 {
2226 struct symbol *base_type;
2227
2228 if (!sym)
2229 return NULL;
2230 current_pos = sym->pos;
2231 base_type = sym->ctype.base_type;
2232 if (!base_type)
2233 return NULL;
2234 if (base_type->type == SYM_FN)
2235 return linearize_fn(sym, base_type);
2236 return NULL;
2237 }
Static analysis for C