Commit | Line | Data |
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98fa08a5 | 1 | // SPDX-License-Identifier: LGPL-2.1-or-later |
d16005f8 | 2 | /* |
98fa08a5 | 3 | * Copyright (C) 2014-2021 Paul Cercueil <paul@crapouillou.net> |
d16005f8 PC |
4 | */ |
5 | ||
9259d748 | 6 | #include "constprop.h" |
98fa08a5 | 7 | #include "lightrec-config.h" |
d16005f8 PC |
8 | #include "disassembler.h" |
9 | #include "lightrec.h" | |
10 | #include "memmanager.h" | |
11 | #include "optimizer.h" | |
12 | #include "regcache.h" | |
13 | ||
14 | #include <errno.h> | |
15 | #include <stdbool.h> | |
16 | #include <stdlib.h> | |
98fa08a5 PC |
17 | #include <string.h> |
18 | ||
19 | #define IF_OPT(opt, ptr) ((opt) ? (ptr) : NULL) | |
d16005f8 PC |
20 | |
21 | struct optimizer_list { | |
22 | void (**optimizers)(struct opcode *); | |
23 | unsigned int nb_optimizers; | |
24 | }; | |
25 | ||
98fa08a5 PC |
26 | static bool is_nop(union code op); |
27 | ||
28 | bool is_unconditional_jump(union code c) | |
29 | { | |
30 | switch (c.i.op) { | |
31 | case OP_SPECIAL: | |
32 | return c.r.op == OP_SPECIAL_JR || c.r.op == OP_SPECIAL_JALR; | |
33 | case OP_J: | |
34 | case OP_JAL: | |
35 | return true; | |
36 | case OP_BEQ: | |
37 | case OP_BLEZ: | |
38 | return c.i.rs == c.i.rt; | |
39 | case OP_REGIMM: | |
40 | return (c.r.rt == OP_REGIMM_BGEZ || | |
41 | c.r.rt == OP_REGIMM_BGEZAL) && c.i.rs == 0; | |
42 | default: | |
43 | return false; | |
44 | } | |
45 | } | |
46 | ||
47 | bool is_syscall(union code c) | |
48 | { | |
49 | return (c.i.op == OP_SPECIAL && c.r.op == OP_SPECIAL_SYSCALL) || | |
50 | (c.i.op == OP_CP0 && (c.r.rs == OP_CP0_MTC0 || | |
51 | c.r.rs == OP_CP0_CTC0) && | |
52 | (c.r.rd == 12 || c.r.rd == 13)); | |
53 | } | |
54 | ||
55 | static u64 opcode_read_mask(union code op) | |
d16005f8 PC |
56 | { |
57 | switch (op.i.op) { | |
58 | case OP_SPECIAL: | |
59 | switch (op.r.op) { | |
60 | case OP_SPECIAL_SYSCALL: | |
61 | case OP_SPECIAL_BREAK: | |
98fa08a5 | 62 | return 0; |
d16005f8 PC |
63 | case OP_SPECIAL_JR: |
64 | case OP_SPECIAL_JALR: | |
65 | case OP_SPECIAL_MTHI: | |
66 | case OP_SPECIAL_MTLO: | |
98fa08a5 | 67 | return BIT(op.r.rs); |
d16005f8 | 68 | case OP_SPECIAL_MFHI: |
98fa08a5 | 69 | return BIT(REG_HI); |
d16005f8 | 70 | case OP_SPECIAL_MFLO: |
98fa08a5 | 71 | return BIT(REG_LO); |
d16005f8 | 72 | case OP_SPECIAL_SLL: |
03535202 PC |
73 | if (!op.r.imm) |
74 | return 0; | |
75 | fallthrough; | |
d16005f8 PC |
76 | case OP_SPECIAL_SRL: |
77 | case OP_SPECIAL_SRA: | |
98fa08a5 | 78 | return BIT(op.r.rt); |
d16005f8 | 79 | default: |
98fa08a5 | 80 | return BIT(op.r.rs) | BIT(op.r.rt); |
d16005f8 PC |
81 | } |
82 | case OP_CP0: | |
83 | switch (op.r.rs) { | |
84 | case OP_CP0_MTC0: | |
85 | case OP_CP0_CTC0: | |
98fa08a5 | 86 | return BIT(op.r.rt); |
d16005f8 | 87 | default: |
98fa08a5 | 88 | return 0; |
d16005f8 PC |
89 | } |
90 | case OP_CP2: | |
91 | if (op.r.op == OP_CP2_BASIC) { | |
92 | switch (op.r.rs) { | |
93 | case OP_CP2_BASIC_MTC2: | |
94 | case OP_CP2_BASIC_CTC2: | |
98fa08a5 | 95 | return BIT(op.r.rt); |
d16005f8 | 96 | default: |
98fa08a5 | 97 | break; |
d16005f8 | 98 | } |
d16005f8 | 99 | } |
98fa08a5 | 100 | return 0; |
d16005f8 PC |
101 | case OP_J: |
102 | case OP_JAL: | |
103 | case OP_LUI: | |
98fa08a5 | 104 | return 0; |
d16005f8 | 105 | case OP_BEQ: |
03535202 PC |
106 | if (op.i.rs == op.i.rt) |
107 | return 0; | |
108 | fallthrough; | |
d16005f8 PC |
109 | case OP_BNE: |
110 | case OP_LWL: | |
111 | case OP_LWR: | |
112 | case OP_SB: | |
113 | case OP_SH: | |
114 | case OP_SWL: | |
115 | case OP_SW: | |
116 | case OP_SWR: | |
98fa08a5 | 117 | return BIT(op.i.rs) | BIT(op.i.rt); |
cb72ea13 PC |
118 | case OP_META: |
119 | return BIT(op.m.rs); | |
d16005f8 | 120 | default: |
98fa08a5 | 121 | return BIT(op.i.rs); |
d16005f8 PC |
122 | } |
123 | } | |
124 | ||
ba3814c1 | 125 | static u64 mult_div_write_mask(union code op) |
d16005f8 | 126 | { |
98fa08a5 PC |
127 | u64 flags; |
128 | ||
ba3814c1 PC |
129 | if (!OPT_FLAG_MULT_DIV) |
130 | return BIT(REG_LO) | BIT(REG_HI); | |
131 | ||
132 | if (op.r.rd) | |
133 | flags = BIT(op.r.rd); | |
134 | else | |
135 | flags = BIT(REG_LO); | |
136 | if (op.r.imm) | |
137 | flags |= BIT(op.r.imm); | |
138 | else | |
139 | flags |= BIT(REG_HI); | |
140 | ||
141 | return flags; | |
142 | } | |
143 | ||
cb72ea13 | 144 | u64 opcode_write_mask(union code op) |
ba3814c1 | 145 | { |
d16005f8 | 146 | switch (op.i.op) { |
ba3814c1 PC |
147 | case OP_META_MULT2: |
148 | case OP_META_MULTU2: | |
149 | return mult_div_write_mask(op); | |
cb72ea13 PC |
150 | case OP_META: |
151 | return BIT(op.m.rd); | |
d16005f8 PC |
152 | case OP_SPECIAL: |
153 | switch (op.r.op) { | |
154 | case OP_SPECIAL_JR: | |
d16005f8 PC |
155 | case OP_SPECIAL_SYSCALL: |
156 | case OP_SPECIAL_BREAK: | |
98fa08a5 | 157 | return 0; |
d16005f8 PC |
158 | case OP_SPECIAL_MULT: |
159 | case OP_SPECIAL_MULTU: | |
160 | case OP_SPECIAL_DIV: | |
161 | case OP_SPECIAL_DIVU: | |
ba3814c1 | 162 | return mult_div_write_mask(op); |
d16005f8 | 163 | case OP_SPECIAL_MTHI: |
98fa08a5 | 164 | return BIT(REG_HI); |
d16005f8 | 165 | case OP_SPECIAL_MTLO: |
98fa08a5 | 166 | return BIT(REG_LO); |
03535202 PC |
167 | case OP_SPECIAL_SLL: |
168 | if (!op.r.imm) | |
169 | return 0; | |
170 | fallthrough; | |
d16005f8 | 171 | default: |
98fa08a5 | 172 | return BIT(op.r.rd); |
d16005f8 PC |
173 | } |
174 | case OP_ADDI: | |
175 | case OP_ADDIU: | |
176 | case OP_SLTI: | |
177 | case OP_SLTIU: | |
178 | case OP_ANDI: | |
179 | case OP_ORI: | |
180 | case OP_XORI: | |
181 | case OP_LUI: | |
182 | case OP_LB: | |
183 | case OP_LH: | |
184 | case OP_LWL: | |
185 | case OP_LW: | |
186 | case OP_LBU: | |
187 | case OP_LHU: | |
188 | case OP_LWR: | |
98fa08a5 PC |
189 | return BIT(op.i.rt); |
190 | case OP_JAL: | |
191 | return BIT(31); | |
d16005f8 PC |
192 | case OP_CP0: |
193 | switch (op.r.rs) { | |
194 | case OP_CP0_MFC0: | |
195 | case OP_CP0_CFC0: | |
98fa08a5 | 196 | return BIT(op.i.rt); |
d16005f8 | 197 | default: |
98fa08a5 | 198 | return 0; |
d16005f8 PC |
199 | } |
200 | case OP_CP2: | |
201 | if (op.r.op == OP_CP2_BASIC) { | |
202 | switch (op.r.rs) { | |
203 | case OP_CP2_BASIC_MFC2: | |
204 | case OP_CP2_BASIC_CFC2: | |
98fa08a5 | 205 | return BIT(op.i.rt); |
d16005f8 | 206 | default: |
98fa08a5 | 207 | break; |
d16005f8 | 208 | } |
98fa08a5 PC |
209 | } |
210 | return 0; | |
211 | case OP_REGIMM: | |
212 | switch (op.r.rt) { | |
213 | case OP_REGIMM_BLTZAL: | |
214 | case OP_REGIMM_BGEZAL: | |
215 | return BIT(31); | |
216 | default: | |
217 | return 0; | |
d16005f8 | 218 | } |
d16005f8 | 219 | default: |
98fa08a5 PC |
220 | return 0; |
221 | } | |
222 | } | |
223 | ||
224 | bool opcode_reads_register(union code op, u8 reg) | |
225 | { | |
226 | return opcode_read_mask(op) & BIT(reg); | |
227 | } | |
228 | ||
229 | bool opcode_writes_register(union code op, u8 reg) | |
230 | { | |
231 | return opcode_write_mask(op) & BIT(reg); | |
232 | } | |
233 | ||
234 | static int find_prev_writer(const struct opcode *list, unsigned int offset, u8 reg) | |
235 | { | |
236 | union code c; | |
237 | unsigned int i; | |
238 | ||
03535202 | 239 | if (op_flag_sync(list[offset].flags)) |
98fa08a5 PC |
240 | return -1; |
241 | ||
242 | for (i = offset; i > 0; i--) { | |
243 | c = list[i - 1].c; | |
244 | ||
245 | if (opcode_writes_register(c, reg)) { | |
246 | if (i > 1 && has_delay_slot(list[i - 2].c)) | |
247 | break; | |
248 | ||
249 | return i - 1; | |
250 | } | |
251 | ||
03535202 | 252 | if (op_flag_sync(list[i - 1].flags) || |
98fa08a5 PC |
253 | has_delay_slot(c) || |
254 | opcode_reads_register(c, reg)) | |
255 | break; | |
256 | } | |
257 | ||
258 | return -1; | |
259 | } | |
260 | ||
261 | static int find_next_reader(const struct opcode *list, unsigned int offset, u8 reg) | |
262 | { | |
263 | unsigned int i; | |
264 | union code c; | |
265 | ||
03535202 | 266 | if (op_flag_sync(list[offset].flags)) |
98fa08a5 PC |
267 | return -1; |
268 | ||
269 | for (i = offset; ; i++) { | |
270 | c = list[i].c; | |
271 | ||
9259d748 | 272 | if (opcode_reads_register(c, reg)) |
98fa08a5 | 273 | return i; |
98fa08a5 | 274 | |
9259d748 PC |
275 | if (op_flag_sync(list[i].flags) |
276 | || (op_flag_no_ds(list[i].flags) && has_delay_slot(c)) | |
277 | || is_delay_slot(list, i) | |
278 | || opcode_writes_register(c, reg)) | |
98fa08a5 PC |
279 | break; |
280 | } | |
281 | ||
282 | return -1; | |
283 | } | |
284 | ||
285 | static bool reg_is_dead(const struct opcode *list, unsigned int offset, u8 reg) | |
286 | { | |
287 | unsigned int i; | |
288 | ||
9259d748 | 289 | if (op_flag_sync(list[offset].flags) || is_delay_slot(list, offset)) |
d16005f8 | 290 | return false; |
98fa08a5 PC |
291 | |
292 | for (i = offset + 1; ; i++) { | |
293 | if (opcode_reads_register(list[i].c, reg)) | |
294 | return false; | |
295 | ||
296 | if (opcode_writes_register(list[i].c, reg)) | |
297 | return true; | |
298 | ||
299 | if (has_delay_slot(list[i].c)) { | |
03535202 | 300 | if (op_flag_no_ds(list[i].flags) || |
22eee2ac | 301 | opcode_reads_register(list[i + 1].c, reg)) |
98fa08a5 PC |
302 | return false; |
303 | ||
304 | return opcode_writes_register(list[i + 1].c, reg); | |
305 | } | |
d16005f8 PC |
306 | } |
307 | } | |
308 | ||
98fa08a5 PC |
309 | static bool reg_is_read(const struct opcode *list, |
310 | unsigned int a, unsigned int b, u8 reg) | |
311 | { | |
312 | /* Return true if reg is read in one of the opcodes of the interval | |
313 | * [a, b[ */ | |
314 | for (; a < b; a++) { | |
315 | if (!is_nop(list[a].c) && opcode_reads_register(list[a].c, reg)) | |
316 | return true; | |
317 | } | |
318 | ||
319 | return false; | |
320 | } | |
321 | ||
322 | static bool reg_is_written(const struct opcode *list, | |
323 | unsigned int a, unsigned int b, u8 reg) | |
324 | { | |
325 | /* Return true if reg is written in one of the opcodes of the interval | |
326 | * [a, b[ */ | |
327 | ||
328 | for (; a < b; a++) { | |
329 | if (!is_nop(list[a].c) && opcode_writes_register(list[a].c, reg)) | |
330 | return true; | |
331 | } | |
332 | ||
333 | return false; | |
334 | } | |
335 | ||
336 | static bool reg_is_read_or_written(const struct opcode *list, | |
337 | unsigned int a, unsigned int b, u8 reg) | |
338 | { | |
339 | return reg_is_read(list, a, b, reg) || reg_is_written(list, a, b, reg); | |
340 | } | |
341 | ||
cb72ea13 PC |
342 | bool opcode_is_mfc(union code op) |
343 | { | |
344 | switch (op.i.op) { | |
345 | case OP_CP0: | |
346 | switch (op.r.rs) { | |
347 | case OP_CP0_MFC0: | |
348 | case OP_CP0_CFC0: | |
349 | return true; | |
350 | default: | |
351 | break; | |
352 | } | |
353 | ||
354 | break; | |
355 | case OP_CP2: | |
356 | if (op.r.op == OP_CP2_BASIC) { | |
357 | switch (op.r.rs) { | |
358 | case OP_CP2_BASIC_MFC2: | |
359 | case OP_CP2_BASIC_CFC2: | |
360 | return true; | |
361 | default: | |
362 | break; | |
363 | } | |
364 | } | |
365 | ||
366 | break; | |
367 | default: | |
368 | break; | |
369 | } | |
370 | ||
371 | return false; | |
372 | } | |
373 | ||
374 | bool opcode_is_load(union code op) | |
98fa08a5 PC |
375 | { |
376 | switch (op.i.op) { | |
377 | case OP_LB: | |
378 | case OP_LH: | |
379 | case OP_LWL: | |
380 | case OP_LW: | |
381 | case OP_LBU: | |
382 | case OP_LHU: | |
383 | case OP_LWR: | |
384 | case OP_LWC2: | |
385 | return true; | |
386 | default: | |
387 | return false; | |
388 | } | |
389 | } | |
390 | ||
391 | static bool opcode_is_store(union code op) | |
392 | { | |
393 | switch (op.i.op) { | |
394 | case OP_SB: | |
395 | case OP_SH: | |
396 | case OP_SW: | |
397 | case OP_SWL: | |
398 | case OP_SWR: | |
399 | case OP_SWC2: | |
400 | return true; | |
401 | default: | |
402 | return false; | |
403 | } | |
404 | } | |
405 | ||
ba3814c1 PC |
406 | static u8 opcode_get_io_size(union code op) |
407 | { | |
408 | switch (op.i.op) { | |
409 | case OP_LB: | |
410 | case OP_LBU: | |
411 | case OP_SB: | |
412 | return 8; | |
413 | case OP_LH: | |
414 | case OP_LHU: | |
415 | case OP_SH: | |
416 | return 16; | |
417 | default: | |
418 | return 32; | |
419 | } | |
420 | } | |
421 | ||
98fa08a5 PC |
422 | bool opcode_is_io(union code op) |
423 | { | |
424 | return opcode_is_load(op) || opcode_is_store(op); | |
425 | } | |
426 | ||
d16005f8 PC |
427 | /* TODO: Complete */ |
428 | static bool is_nop(union code op) | |
429 | { | |
430 | if (opcode_writes_register(op, 0)) { | |
431 | switch (op.i.op) { | |
432 | case OP_CP0: | |
433 | return op.r.rs != OP_CP0_MFC0; | |
434 | case OP_LB: | |
435 | case OP_LH: | |
436 | case OP_LWL: | |
437 | case OP_LW: | |
438 | case OP_LBU: | |
439 | case OP_LHU: | |
440 | case OP_LWR: | |
441 | return false; | |
442 | default: | |
443 | return true; | |
444 | } | |
445 | } | |
446 | ||
447 | switch (op.i.op) { | |
448 | case OP_SPECIAL: | |
449 | switch (op.r.op) { | |
450 | case OP_SPECIAL_AND: | |
451 | return op.r.rd == op.r.rt && op.r.rd == op.r.rs; | |
452 | case OP_SPECIAL_ADD: | |
453 | case OP_SPECIAL_ADDU: | |
454 | return (op.r.rd == op.r.rt && op.r.rs == 0) || | |
455 | (op.r.rd == op.r.rs && op.r.rt == 0); | |
456 | case OP_SPECIAL_SUB: | |
457 | case OP_SPECIAL_SUBU: | |
458 | return op.r.rd == op.r.rs && op.r.rt == 0; | |
459 | case OP_SPECIAL_OR: | |
460 | if (op.r.rd == op.r.rt) | |
461 | return op.r.rd == op.r.rs || op.r.rs == 0; | |
462 | else | |
463 | return (op.r.rd == op.r.rs) && op.r.rt == 0; | |
464 | case OP_SPECIAL_SLL: | |
465 | case OP_SPECIAL_SRA: | |
466 | case OP_SPECIAL_SRL: | |
467 | return op.r.rd == op.r.rt && op.r.imm == 0; | |
98fa08a5 PC |
468 | case OP_SPECIAL_MFHI: |
469 | case OP_SPECIAL_MFLO: | |
470 | return op.r.rd == 0; | |
d16005f8 PC |
471 | default: |
472 | return false; | |
473 | } | |
474 | case OP_ORI: | |
475 | case OP_ADDI: | |
476 | case OP_ADDIU: | |
477 | return op.i.rt == op.i.rs && op.i.imm == 0; | |
478 | case OP_BGTZ: | |
479 | return (op.i.rs == 0 || op.i.imm == 1); | |
480 | case OP_REGIMM: | |
481 | return (op.i.op == OP_REGIMM_BLTZ || | |
482 | op.i.op == OP_REGIMM_BLTZAL) && | |
483 | (op.i.rs == 0 || op.i.imm == 1); | |
484 | case OP_BNE: | |
485 | return (op.i.rs == op.i.rt || op.i.imm == 1); | |
486 | default: | |
487 | return false; | |
488 | } | |
489 | } | |
490 | ||
9259d748 PC |
491 | static void lightrec_optimize_sll_sra(struct opcode *list, unsigned int offset, |
492 | struct constprop_data *v) | |
d16005f8 | 493 | { |
9259d748 | 494 | struct opcode *ldop = NULL, *curr = &list[offset], *next; |
98fa08a5 PC |
495 | struct opcode *to_change, *to_nop; |
496 | int idx, idx2; | |
d16005f8 | 497 | |
98fa08a5 PC |
498 | if (curr->r.imm != 24 && curr->r.imm != 16) |
499 | return; | |
500 | ||
9259d748 PC |
501 | if (is_delay_slot(list, offset)) |
502 | return; | |
503 | ||
504 | idx = find_next_reader(list, offset + 1, curr->r.rd); | |
98fa08a5 PC |
505 | if (idx < 0) |
506 | return; | |
507 | ||
9259d748 | 508 | next = &list[idx]; |
98fa08a5 | 509 | |
9259d748 PC |
510 | if (next->i.op != OP_SPECIAL || next->r.op != OP_SPECIAL_SRA || |
511 | next->r.imm != curr->r.imm || next->r.rt != curr->r.rd) | |
98fa08a5 | 512 | return; |
d16005f8 | 513 | |
9259d748 | 514 | if (curr->r.rd != curr->r.rt && next->r.rd != next->r.rt) { |
98fa08a5 PC |
515 | /* sll rY, rX, 16 |
516 | * ... | |
9259d748 | 517 | * sra rZ, rY, 16 */ |
d16005f8 | 518 | |
9259d748 PC |
519 | if (!reg_is_dead(list, idx, curr->r.rd) || |
520 | reg_is_read_or_written(list, offset, idx, next->r.rd)) | |
98fa08a5 PC |
521 | return; |
522 | ||
523 | /* If rY is dead after the SRL, and rZ is not used after the SLL, | |
524 | * we can change rY to rZ */ | |
525 | ||
526 | pr_debug("Detected SLL/SRA with middle temp register\n"); | |
9259d748 PC |
527 | curr->r.rd = next->r.rd; |
528 | next->r.rt = curr->r.rd; | |
98fa08a5 PC |
529 | } |
530 | ||
9259d748 PC |
531 | /* We got a SLL/SRA combo. If imm #16, that's a cast to s16. |
532 | * If imm #24 that's a cast to s8. | |
98fa08a5 PC |
533 | * |
534 | * First of all, make sure that the target register of the SLL is not | |
9259d748 | 535 | * read after the SRA. */ |
98fa08a5 | 536 | |
9259d748 | 537 | if (curr->r.rd == curr->r.rt) { |
98fa08a5 PC |
538 | /* sll rX, rX, 16 |
539 | * ... | |
9259d748 PC |
540 | * sra rY, rX, 16 */ |
541 | to_change = next; | |
542 | to_nop = curr; | |
98fa08a5 PC |
543 | |
544 | /* rX is used after the SRA - we cannot convert it. */ | |
9259d748 | 545 | if (curr->r.rd != next->r.rd && !reg_is_dead(list, idx, curr->r.rd)) |
98fa08a5 | 546 | return; |
d16005f8 | 547 | } else { |
98fa08a5 PC |
548 | /* sll rY, rX, 16 |
549 | * ... | |
9259d748 PC |
550 | * sra rY, rY, 16 */ |
551 | to_change = curr; | |
552 | to_nop = next; | |
d16005f8 PC |
553 | } |
554 | ||
9259d748 | 555 | idx2 = find_prev_writer(list, offset, curr->r.rt); |
98fa08a5 PC |
556 | if (idx2 >= 0) { |
557 | /* Note that PSX games sometimes do casts after | |
558 | * a LHU or LBU; in this case we can change the | |
559 | * load opcode to a LH or LB, and the cast can | |
560 | * be changed to a MOV or a simple NOP. */ | |
561 | ||
9259d748 | 562 | ldop = &list[idx2]; |
98fa08a5 | 563 | |
9259d748 PC |
564 | if (next->r.rd != ldop->i.rt && |
565 | !reg_is_dead(list, idx, ldop->i.rt)) | |
566 | ldop = NULL; | |
567 | else if (curr->r.imm == 16 && ldop->i.op == OP_LHU) | |
568 | ldop->i.op = OP_LH; | |
569 | else if (curr->r.imm == 24 && ldop->i.op == OP_LBU) | |
570 | ldop->i.op = OP_LB; | |
98fa08a5 | 571 | else |
9259d748 | 572 | ldop = NULL; |
98fa08a5 | 573 | |
9259d748 PC |
574 | if (ldop) { |
575 | if (next->r.rd == ldop->i.rt) { | |
98fa08a5 | 576 | to_change->opcode = 0; |
9259d748 PC |
577 | } else if (reg_is_dead(list, idx, ldop->i.rt) && |
578 | !reg_is_read_or_written(list, idx2 + 1, idx, next->r.rd)) { | |
98fa08a5 PC |
579 | /* The target register of the SRA is dead after the |
580 | * LBU/LHU; we can change the target register of the | |
581 | * LBU/LHU to the one of the SRA. */ | |
9259d748 PC |
582 | v[ldop->i.rt].known = 0; |
583 | v[ldop->i.rt].sign = 0; | |
584 | ldop->i.rt = next->r.rd; | |
98fa08a5 PC |
585 | to_change->opcode = 0; |
586 | } else { | |
cb72ea13 PC |
587 | to_change->i.op = OP_META; |
588 | to_change->m.op = OP_META_MOV; | |
589 | to_change->m.rd = next->r.rd; | |
590 | to_change->m.rs = ldop->i.rt; | |
98fa08a5 | 591 | } |
d16005f8 | 592 | |
98fa08a5 PC |
593 | if (to_nop->r.imm == 24) |
594 | pr_debug("Convert LBU+SLL+SRA to LB\n"); | |
595 | else | |
596 | pr_debug("Convert LHU+SLL+SRA to LH\n"); | |
9259d748 PC |
597 | |
598 | v[ldop->i.rt].known = 0; | |
684432ad | 599 | v[ldop->i.rt].sign = 0xffffff80 << (24 - curr->r.imm); |
98fa08a5 PC |
600 | } |
601 | } | |
602 | ||
9259d748 | 603 | if (!ldop) { |
98fa08a5 | 604 | pr_debug("Convert SLL/SRA #%u to EXT%c\n", |
9259d748 | 605 | curr->r.imm, curr->r.imm == 24 ? 'C' : 'S'); |
98fa08a5 | 606 | |
cb72ea13 PC |
607 | to_change->m.rs = curr->r.rt; |
608 | to_change->m.op = to_nop->r.imm == 24 ? OP_META_EXTC : OP_META_EXTS; | |
609 | to_change->i.op = OP_META; | |
98fa08a5 PC |
610 | } |
611 | ||
612 | to_nop->opcode = 0; | |
d16005f8 PC |
613 | } |
614 | ||
9259d748 PC |
615 | static void |
616 | lightrec_remove_useless_lui(struct block *block, unsigned int offset, | |
617 | const struct constprop_data *v) | |
02487de7 PC |
618 | { |
619 | struct opcode *list = block->opcode_list, | |
620 | *op = &block->opcode_list[offset]; | |
621 | int reader; | |
622 | ||
9259d748 PC |
623 | if (!op_flag_sync(op->flags) && is_known(v, op->i.rt) && |
624 | v[op->i.rt].value == op->i.imm << 16) { | |
02487de7 PC |
625 | pr_debug("Converting duplicated LUI to NOP\n"); |
626 | op->opcode = 0x0; | |
627 | return; | |
628 | } | |
629 | ||
9259d748 | 630 | if (op->i.imm != 0 || op->i.rt == 0 || offset == block->nb_ops - 1) |
02487de7 PC |
631 | return; |
632 | ||
633 | reader = find_next_reader(list, offset + 1, op->i.rt); | |
634 | if (reader <= 0) | |
635 | return; | |
636 | ||
637 | if (opcode_writes_register(list[reader].c, op->i.rt) || | |
638 | reg_is_dead(list, reader, op->i.rt)) { | |
639 | pr_debug("Removing useless LUI 0x0\n"); | |
640 | ||
641 | if (list[reader].i.rs == op->i.rt) | |
642 | list[reader].i.rs = 0; | |
643 | if (list[reader].i.op == OP_SPECIAL && | |
644 | list[reader].i.rt == op->i.rt) | |
645 | list[reader].i.rt = 0; | |
646 | op->opcode = 0x0; | |
647 | } | |
648 | } | |
649 | ||
684432ad PC |
650 | static void lightrec_lui_to_movi(struct block *block, unsigned int offset) |
651 | { | |
652 | struct opcode *ori, *lui = &block->opcode_list[offset]; | |
653 | int next; | |
654 | ||
655 | if (lui->i.op != OP_LUI) | |
656 | return; | |
657 | ||
658 | next = find_next_reader(block->opcode_list, offset + 1, lui->i.rt); | |
659 | if (next > 0) { | |
660 | ori = &block->opcode_list[next]; | |
661 | ||
662 | switch (ori->i.op) { | |
663 | case OP_ORI: | |
664 | case OP_ADDI: | |
665 | case OP_ADDIU: | |
666 | if (ori->i.rs == ori->i.rt && ori->i.imm) { | |
667 | ori->flags |= LIGHTREC_MOVI; | |
668 | lui->flags |= LIGHTREC_MOVI; | |
669 | } | |
670 | break; | |
671 | } | |
672 | } | |
673 | } | |
674 | ||
02487de7 PC |
675 | static void lightrec_modify_lui(struct block *block, unsigned int offset) |
676 | { | |
677 | union code c, *lui = &block->opcode_list[offset].c; | |
678 | bool stop = false, stop_next = false; | |
679 | unsigned int i; | |
680 | ||
681 | for (i = offset + 1; !stop && i < block->nb_ops; i++) { | |
682 | c = block->opcode_list[i].c; | |
683 | stop = stop_next; | |
684 | ||
685 | if ((opcode_is_store(c) && c.i.rt == lui->i.rt) | |
686 | || (!opcode_is_load(c) && opcode_reads_register(c, lui->i.rt))) | |
687 | break; | |
688 | ||
689 | if (opcode_writes_register(c, lui->i.rt)) { | |
cb72ea13 PC |
690 | if (c.i.op == OP_LWL || c.i.op == OP_LWR) { |
691 | /* LWL/LWR only partially write their target register; | |
692 | * therefore the LUI should not write a different value. */ | |
693 | break; | |
694 | } | |
695 | ||
02487de7 | 696 | pr_debug("Convert LUI at offset 0x%x to kuseg\n", |
684432ad | 697 | (i - 1) << 2); |
02487de7 PC |
698 | lui->i.imm = kunseg(lui->i.imm << 16) >> 16; |
699 | break; | |
700 | } | |
701 | ||
702 | if (has_delay_slot(c)) | |
703 | stop_next = true; | |
704 | } | |
705 | } | |
706 | ||
03535202 PC |
707 | static int lightrec_transform_branches(struct lightrec_state *state, |
708 | struct block *block) | |
709 | { | |
710 | struct opcode *op; | |
711 | unsigned int i; | |
712 | s32 offset; | |
713 | ||
714 | for (i = 0; i < block->nb_ops; i++) { | |
715 | op = &block->opcode_list[i]; | |
716 | ||
717 | switch (op->i.op) { | |
718 | case OP_J: | |
719 | /* Transform J opcode into BEQ $zero, $zero if possible. */ | |
720 | offset = (s32)((block->pc & 0xf0000000) >> 2 | op->j.imm) | |
721 | - (s32)(block->pc >> 2) - (s32)i - 1; | |
722 | ||
723 | if (offset == (s16)offset) { | |
724 | pr_debug("Transform J into BEQ $zero, $zero\n"); | |
725 | op->i.op = OP_BEQ; | |
726 | op->i.rs = 0; | |
727 | op->i.rt = 0; | |
728 | op->i.imm = offset; | |
729 | ||
730 | } | |
ba3814c1 PC |
731 | fallthrough; |
732 | default: | |
03535202 PC |
733 | break; |
734 | } | |
735 | } | |
736 | ||
737 | return 0; | |
738 | } | |
739 | ||
ba3814c1 PC |
740 | static inline bool is_power_of_two(u32 value) |
741 | { | |
742 | return popcount32(value) == 1; | |
743 | } | |
744 | ||
9259d748 PC |
745 | static void lightrec_patch_known_zero(struct opcode *op, |
746 | const struct constprop_data *v) | |
747 | { | |
748 | switch (op->i.op) { | |
749 | case OP_SPECIAL: | |
750 | switch (op->r.op) { | |
751 | case OP_SPECIAL_JR: | |
752 | case OP_SPECIAL_JALR: | |
753 | case OP_SPECIAL_MTHI: | |
754 | case OP_SPECIAL_MTLO: | |
755 | if (is_known_zero(v, op->r.rs)) | |
756 | op->r.rs = 0; | |
757 | break; | |
758 | default: | |
759 | if (is_known_zero(v, op->r.rs)) | |
760 | op->r.rs = 0; | |
761 | fallthrough; | |
762 | case OP_SPECIAL_SLL: | |
763 | case OP_SPECIAL_SRL: | |
764 | case OP_SPECIAL_SRA: | |
765 | if (is_known_zero(v, op->r.rt)) | |
766 | op->r.rt = 0; | |
767 | break; | |
768 | case OP_SPECIAL_SYSCALL: | |
769 | case OP_SPECIAL_BREAK: | |
770 | case OP_SPECIAL_MFHI: | |
771 | case OP_SPECIAL_MFLO: | |
772 | break; | |
773 | } | |
774 | break; | |
775 | case OP_CP0: | |
776 | switch (op->r.rs) { | |
777 | case OP_CP0_MTC0: | |
778 | case OP_CP0_CTC0: | |
779 | if (is_known_zero(v, op->r.rt)) | |
780 | op->r.rt = 0; | |
781 | break; | |
782 | default: | |
783 | break; | |
784 | } | |
785 | break; | |
786 | case OP_CP2: | |
787 | if (op->r.op == OP_CP2_BASIC) { | |
788 | switch (op->r.rs) { | |
789 | case OP_CP2_BASIC_MTC2: | |
790 | case OP_CP2_BASIC_CTC2: | |
791 | if (is_known_zero(v, op->r.rt)) | |
792 | op->r.rt = 0; | |
793 | break; | |
794 | default: | |
795 | break; | |
796 | } | |
797 | } | |
798 | break; | |
799 | case OP_BEQ: | |
800 | case OP_BNE: | |
801 | if (is_known_zero(v, op->i.rt)) | |
802 | op->i.rt = 0; | |
803 | fallthrough; | |
804 | case OP_REGIMM: | |
805 | case OP_BLEZ: | |
806 | case OP_BGTZ: | |
807 | case OP_ADDI: | |
808 | case OP_ADDIU: | |
809 | case OP_SLTI: | |
810 | case OP_SLTIU: | |
811 | case OP_ANDI: | |
812 | case OP_ORI: | |
813 | case OP_XORI: | |
9259d748 PC |
814 | case OP_META_MULT2: |
815 | case OP_META_MULTU2: | |
cb72ea13 PC |
816 | case OP_META: |
817 | if (is_known_zero(v, op->m.rs)) | |
818 | op->m.rs = 0; | |
9259d748 PC |
819 | break; |
820 | case OP_SB: | |
821 | case OP_SH: | |
822 | case OP_SWL: | |
823 | case OP_SW: | |
824 | case OP_SWR: | |
825 | if (is_known_zero(v, op->i.rt)) | |
826 | op->i.rt = 0; | |
827 | fallthrough; | |
828 | case OP_LB: | |
829 | case OP_LH: | |
830 | case OP_LWL: | |
831 | case OP_LW: | |
832 | case OP_LBU: | |
833 | case OP_LHU: | |
834 | case OP_LWR: | |
835 | case OP_LWC2: | |
836 | case OP_SWC2: | |
837 | if (is_known(v, op->i.rs) | |
838 | && kunseg(v[op->i.rs].value) == 0) | |
839 | op->i.rs = 0; | |
840 | break; | |
841 | default: | |
842 | break; | |
843 | } | |
844 | } | |
845 | ||
846 | static void lightrec_reset_syncs(struct block *block) | |
847 | { | |
848 | struct opcode *op, *list = block->opcode_list; | |
849 | unsigned int i; | |
850 | s32 offset; | |
851 | ||
852 | for (i = 0; i < block->nb_ops; i++) | |
853 | list[i].flags &= ~LIGHTREC_SYNC; | |
854 | ||
855 | for (i = 0; i < block->nb_ops; i++) { | |
856 | op = &list[i]; | |
857 | ||
cb72ea13 PC |
858 | if (has_delay_slot(op->c)) { |
859 | if (op_flag_local_branch(op->flags)) { | |
860 | offset = i + 1 - op_flag_no_ds(op->flags) + (s16)op->i.imm; | |
861 | list[offset].flags |= LIGHTREC_SYNC; | |
862 | } | |
863 | ||
864 | if (op_flag_emulate_branch(op->flags) && i + 2 < block->nb_ops) | |
865 | list[i + 2].flags |= LIGHTREC_SYNC; | |
9259d748 PC |
866 | } |
867 | } | |
868 | } | |
869 | ||
98fa08a5 | 870 | static int lightrec_transform_ops(struct lightrec_state *state, struct block *block) |
d16005f8 | 871 | { |
9259d748 PC |
872 | struct opcode *op, *list = block->opcode_list; |
873 | struct constprop_data v[32] = LIGHTREC_CONSTPROP_INITIALIZER; | |
98fa08a5 | 874 | unsigned int i; |
9259d748 | 875 | bool local; |
ba3814c1 | 876 | u8 tmp; |
d16005f8 | 877 | |
98fa08a5 PC |
878 | for (i = 0; i < block->nb_ops; i++) { |
879 | op = &list[i]; | |
d16005f8 | 880 | |
cb72ea13 | 881 | lightrec_consts_propagate(block, i, v); |
9259d748 PC |
882 | |
883 | lightrec_patch_known_zero(op, v); | |
22eee2ac | 884 | |
d16005f8 PC |
885 | /* Transform all opcodes detected as useless to real NOPs |
886 | * (0x0: SLL r0, r0, #0) */ | |
98fa08a5 | 887 | if (op->opcode != 0 && is_nop(op->c)) { |
d16005f8 | 888 | pr_debug("Converting useless opcode 0x%08x to NOP\n", |
98fa08a5 PC |
889 | op->opcode); |
890 | op->opcode = 0x0; | |
d16005f8 PC |
891 | } |
892 | ||
98fa08a5 | 893 | if (!op->opcode) |
d16005f8 PC |
894 | continue; |
895 | ||
98fa08a5 | 896 | switch (op->i.op) { |
d16005f8 | 897 | case OP_BEQ: |
9259d748 PC |
898 | if (op->i.rs == op->i.rt || |
899 | (is_known(v, op->i.rs) && is_known(v, op->i.rt) && | |
900 | v[op->i.rs].value == v[op->i.rt].value)) { | |
901 | if (op->i.rs != op->i.rt) | |
902 | pr_debug("Found always-taken BEQ\n"); | |
903 | ||
98fa08a5 PC |
904 | op->i.rs = 0; |
905 | op->i.rt = 0; | |
9259d748 PC |
906 | } else if (v[op->i.rs].known & v[op->i.rt].known & |
907 | (v[op->i.rs].value ^ v[op->i.rt].value)) { | |
908 | pr_debug("Found never-taken BEQ\n"); | |
909 | ||
910 | local = op_flag_local_branch(op->flags); | |
911 | op->opcode = 0; | |
912 | op->flags = 0; | |
913 | ||
914 | if (local) | |
915 | lightrec_reset_syncs(block); | |
98fa08a5 PC |
916 | } else if (op->i.rs == 0) { |
917 | op->i.rs = op->i.rt; | |
918 | op->i.rt = 0; | |
d16005f8 PC |
919 | } |
920 | break; | |
98fa08a5 | 921 | |
d16005f8 | 922 | case OP_BNE: |
9259d748 PC |
923 | if (v[op->i.rs].known & v[op->i.rt].known & |
924 | (v[op->i.rs].value ^ v[op->i.rt].value)) { | |
925 | pr_debug("Found always-taken BNE\n"); | |
926 | ||
927 | op->i.op = OP_BEQ; | |
928 | op->i.rs = 0; | |
929 | op->i.rt = 0; | |
930 | } else if (is_known(v, op->i.rs) && is_known(v, op->i.rt) && | |
931 | v[op->i.rs].value == v[op->i.rt].value) { | |
932 | pr_debug("Found never-taken BNE\n"); | |
933 | ||
934 | local = op_flag_local_branch(op->flags); | |
935 | op->opcode = 0; | |
936 | op->flags = 0; | |
937 | ||
938 | if (local) | |
939 | lightrec_reset_syncs(block); | |
940 | } else if (op->i.rs == 0) { | |
98fa08a5 PC |
941 | op->i.rs = op->i.rt; |
942 | op->i.rt = 0; | |
943 | } | |
944 | break; | |
945 | ||
9259d748 PC |
946 | case OP_BLEZ: |
947 | if (v[op->i.rs].known & BIT(31) && | |
948 | v[op->i.rs].value & BIT(31)) { | |
949 | pr_debug("Found always-taken BLEZ\n"); | |
950 | ||
951 | op->i.op = OP_BEQ; | |
952 | op->i.rs = 0; | |
953 | op->i.rt = 0; | |
954 | } | |
955 | break; | |
956 | ||
957 | case OP_BGTZ: | |
958 | if (v[op->i.rs].known & BIT(31) && | |
959 | v[op->i.rs].value & BIT(31)) { | |
960 | pr_debug("Found never-taken BGTZ\n"); | |
961 | ||
962 | local = op_flag_local_branch(op->flags); | |
963 | op->opcode = 0; | |
964 | op->flags = 0; | |
965 | ||
966 | if (local) | |
967 | lightrec_reset_syncs(block); | |
968 | } | |
969 | break; | |
970 | ||
98fa08a5 | 971 | case OP_LUI: |
9259d748 | 972 | if (i == 0 || !has_delay_slot(list[i - 1].c)) |
d8b04acd | 973 | lightrec_modify_lui(block, i); |
9259d748 | 974 | lightrec_remove_useless_lui(block, i, v); |
684432ad PC |
975 | if (i == 0 || !has_delay_slot(list[i - 1].c)) |
976 | lightrec_lui_to_movi(block, i); | |
d16005f8 PC |
977 | break; |
978 | ||
979 | /* Transform ORI/ADDI/ADDIU with imm #0 or ORR/ADD/ADDU/SUB/SUBU | |
980 | * with register $zero to the MOV meta-opcode */ | |
981 | case OP_ORI: | |
982 | case OP_ADDI: | |
983 | case OP_ADDIU: | |
98fa08a5 | 984 | if (op->i.imm == 0) { |
d16005f8 | 985 | pr_debug("Convert ORI/ADDI/ADDIU #0 to MOV\n"); |
cb72ea13 PC |
986 | op->m.rd = op->i.rt; |
987 | op->m.op = OP_META_MOV; | |
988 | op->i.op = OP_META; | |
d16005f8 PC |
989 | } |
990 | break; | |
9259d748 PC |
991 | case OP_ANDI: |
992 | if (bits_are_known_zero(v, op->i.rs, ~op->i.imm)) { | |
993 | pr_debug("Found useless ANDI 0x%x\n", op->i.imm); | |
994 | ||
995 | if (op->i.rs == op->i.rt) { | |
996 | op->opcode = 0; | |
997 | } else { | |
cb72ea13 PC |
998 | op->m.rd = op->i.rt; |
999 | op->m.op = OP_META_MOV; | |
1000 | op->i.op = OP_META; | |
9259d748 PC |
1001 | } |
1002 | } | |
1003 | break; | |
1004 | case OP_REGIMM: | |
1005 | switch (op->r.rt) { | |
1006 | case OP_REGIMM_BLTZ: | |
1007 | case OP_REGIMM_BGEZ: | |
1008 | if (!(v[op->r.rs].known & BIT(31))) | |
1009 | break; | |
1010 | ||
1011 | if (!!(v[op->r.rs].value & BIT(31)) | |
1012 | ^ (op->r.rt == OP_REGIMM_BGEZ)) { | |
1013 | pr_debug("Found always-taken BLTZ/BGEZ\n"); | |
1014 | op->i.op = OP_BEQ; | |
1015 | op->i.rs = 0; | |
1016 | op->i.rt = 0; | |
1017 | } else { | |
1018 | pr_debug("Found never-taken BLTZ/BGEZ\n"); | |
1019 | ||
1020 | local = op_flag_local_branch(op->flags); | |
1021 | op->opcode = 0; | |
1022 | op->flags = 0; | |
1023 | ||
1024 | if (local) | |
1025 | lightrec_reset_syncs(block); | |
1026 | } | |
1027 | break; | |
1028 | case OP_REGIMM_BLTZAL: | |
1029 | case OP_REGIMM_BGEZAL: | |
1030 | /* TODO: Detect always-taken and replace with JAL */ | |
1031 | break; | |
1032 | } | |
1033 | break; | |
d16005f8 | 1034 | case OP_SPECIAL: |
98fa08a5 | 1035 | switch (op->r.op) { |
9259d748 PC |
1036 | case OP_SPECIAL_SRAV: |
1037 | if ((v[op->r.rs].known & 0x1f) != 0x1f) | |
1038 | break; | |
1039 | ||
1040 | pr_debug("Convert SRAV to SRA\n"); | |
1041 | op->r.imm = v[op->r.rs].value & 0x1f; | |
1042 | op->r.op = OP_SPECIAL_SRA; | |
1043 | ||
1044 | fallthrough; | |
d16005f8 | 1045 | case OP_SPECIAL_SRA: |
98fa08a5 PC |
1046 | if (op->r.imm == 0) { |
1047 | pr_debug("Convert SRA #0 to MOV\n"); | |
cb72ea13 PC |
1048 | op->m.rs = op->r.rt; |
1049 | op->m.op = OP_META_MOV; | |
1050 | op->i.op = OP_META; | |
98fa08a5 PC |
1051 | break; |
1052 | } | |
98fa08a5 | 1053 | break; |
9259d748 PC |
1054 | |
1055 | case OP_SPECIAL_SLLV: | |
1056 | if ((v[op->r.rs].known & 0x1f) != 0x1f) | |
1057 | break; | |
1058 | ||
1059 | pr_debug("Convert SLLV to SLL\n"); | |
1060 | op->r.imm = v[op->r.rs].value & 0x1f; | |
1061 | op->r.op = OP_SPECIAL_SLL; | |
1062 | ||
1063 | fallthrough; | |
98fa08a5 | 1064 | case OP_SPECIAL_SLL: |
9259d748 PC |
1065 | if (op->r.imm == 0) { |
1066 | pr_debug("Convert SLL #0 to MOV\n"); | |
cb72ea13 PC |
1067 | op->m.rs = op->r.rt; |
1068 | op->m.op = OP_META_MOV; | |
1069 | op->i.op = OP_META; | |
9259d748 PC |
1070 | } |
1071 | ||
1072 | lightrec_optimize_sll_sra(block->opcode_list, i, v); | |
1073 | break; | |
1074 | ||
1075 | case OP_SPECIAL_SRLV: | |
1076 | if ((v[op->r.rs].known & 0x1f) != 0x1f) | |
1077 | break; | |
1078 | ||
1079 | pr_debug("Convert SRLV to SRL\n"); | |
1080 | op->r.imm = v[op->r.rs].value & 0x1f; | |
1081 | op->r.op = OP_SPECIAL_SRL; | |
1082 | ||
1083 | fallthrough; | |
d16005f8 | 1084 | case OP_SPECIAL_SRL: |
98fa08a5 | 1085 | if (op->r.imm == 0) { |
9259d748 | 1086 | pr_debug("Convert SRL #0 to MOV\n"); |
cb72ea13 PC |
1087 | op->m.rs = op->r.rt; |
1088 | op->m.op = OP_META_MOV; | |
1089 | op->i.op = OP_META; | |
d16005f8 PC |
1090 | } |
1091 | break; | |
9259d748 | 1092 | |
ba3814c1 PC |
1093 | case OP_SPECIAL_MULT: |
1094 | case OP_SPECIAL_MULTU: | |
9259d748 PC |
1095 | if (is_known(v, op->r.rs) && |
1096 | is_power_of_two(v[op->r.rs].value)) { | |
ba3814c1 PC |
1097 | tmp = op->c.i.rs; |
1098 | op->c.i.rs = op->c.i.rt; | |
1099 | op->c.i.rt = tmp; | |
9259d748 PC |
1100 | } else if (!is_known(v, op->r.rt) || |
1101 | !is_power_of_two(v[op->r.rt].value)) { | |
ba3814c1 PC |
1102 | break; |
1103 | } | |
1104 | ||
1105 | pr_debug("Multiply by power-of-two: %u\n", | |
9259d748 | 1106 | v[op->r.rt].value); |
ba3814c1 PC |
1107 | |
1108 | if (op->r.op == OP_SPECIAL_MULT) | |
1109 | op->i.op = OP_META_MULT2; | |
1110 | else | |
1111 | op->i.op = OP_META_MULTU2; | |
1112 | ||
9259d748 | 1113 | op->r.op = ctz32(v[op->r.rt].value); |
ba3814c1 | 1114 | break; |
cb72ea13 PC |
1115 | case OP_SPECIAL_NOR: |
1116 | if (op->r.rs == 0 || op->r.rt == 0) { | |
1117 | pr_debug("Convert NOR $zero to COM\n"); | |
1118 | op->i.op = OP_META; | |
1119 | op->m.op = OP_META_COM; | |
1120 | if (!op->m.rs) | |
1121 | op->m.rs = op->r.rt; | |
1122 | } | |
1123 | break; | |
d16005f8 PC |
1124 | case OP_SPECIAL_OR: |
1125 | case OP_SPECIAL_ADD: | |
1126 | case OP_SPECIAL_ADDU: | |
98fa08a5 | 1127 | if (op->r.rs == 0) { |
d16005f8 | 1128 | pr_debug("Convert OR/ADD $zero to MOV\n"); |
cb72ea13 PC |
1129 | op->m.rs = op->r.rt; |
1130 | op->m.op = OP_META_MOV; | |
1131 | op->i.op = OP_META; | |
d16005f8 | 1132 | } |
d8b04acd PC |
1133 | fallthrough; |
1134 | case OP_SPECIAL_SUB: | |
d16005f8 | 1135 | case OP_SPECIAL_SUBU: |
98fa08a5 | 1136 | if (op->r.rt == 0) { |
d16005f8 | 1137 | pr_debug("Convert OR/ADD/SUB $zero to MOV\n"); |
cb72ea13 PC |
1138 | op->m.op = OP_META_MOV; |
1139 | op->i.op = OP_META; | |
d16005f8 | 1140 | } |
d8b04acd PC |
1141 | fallthrough; |
1142 | default: | |
d16005f8 PC |
1143 | break; |
1144 | } | |
d8b04acd PC |
1145 | fallthrough; |
1146 | default: | |
d16005f8 PC |
1147 | break; |
1148 | } | |
1149 | } | |
1150 | ||
1151 | return 0; | |
1152 | } | |
1153 | ||
ba3814c1 PC |
1154 | static bool lightrec_can_switch_delay_slot(union code op, union code next_op) |
1155 | { | |
1156 | switch (op.i.op) { | |
1157 | case OP_SPECIAL: | |
1158 | switch (op.r.op) { | |
1159 | case OP_SPECIAL_JALR: | |
1160 | if (opcode_reads_register(next_op, op.r.rd) || | |
1161 | opcode_writes_register(next_op, op.r.rd)) | |
1162 | return false; | |
1163 | fallthrough; | |
1164 | case OP_SPECIAL_JR: | |
1165 | if (opcode_writes_register(next_op, op.r.rs)) | |
1166 | return false; | |
1167 | fallthrough; | |
1168 | default: | |
1169 | break; | |
1170 | } | |
1171 | fallthrough; | |
1172 | case OP_J: | |
1173 | break; | |
1174 | case OP_JAL: | |
1175 | if (opcode_reads_register(next_op, 31) || | |
1176 | opcode_writes_register(next_op, 31)) | |
1177 | return false;; | |
1178 | ||
1179 | break; | |
1180 | case OP_BEQ: | |
1181 | case OP_BNE: | |
1182 | if (op.i.rt && opcode_writes_register(next_op, op.i.rt)) | |
1183 | return false; | |
1184 | fallthrough; | |
1185 | case OP_BLEZ: | |
1186 | case OP_BGTZ: | |
1187 | if (op.i.rs && opcode_writes_register(next_op, op.i.rs)) | |
1188 | return false; | |
1189 | break; | |
1190 | case OP_REGIMM: | |
1191 | switch (op.r.rt) { | |
1192 | case OP_REGIMM_BLTZAL: | |
1193 | case OP_REGIMM_BGEZAL: | |
1194 | if (opcode_reads_register(next_op, 31) || | |
1195 | opcode_writes_register(next_op, 31)) | |
1196 | return false; | |
1197 | fallthrough; | |
1198 | case OP_REGIMM_BLTZ: | |
1199 | case OP_REGIMM_BGEZ: | |
1200 | if (op.i.rs && opcode_writes_register(next_op, op.i.rs)) | |
1201 | return false; | |
1202 | break; | |
1203 | } | |
1204 | fallthrough; | |
1205 | default: | |
1206 | break; | |
1207 | } | |
1208 | ||
1209 | return true; | |
1210 | } | |
1211 | ||
98fa08a5 | 1212 | static int lightrec_switch_delay_slots(struct lightrec_state *state, struct block *block) |
d16005f8 | 1213 | { |
98fa08a5 PC |
1214 | struct opcode *list, *next = &block->opcode_list[0]; |
1215 | unsigned int i; | |
1216 | union code op, next_op; | |
03535202 | 1217 | u32 flags; |
d16005f8 | 1218 | |
98fa08a5 PC |
1219 | for (i = 0; i < block->nb_ops - 1; i++) { |
1220 | list = next; | |
1221 | next = &block->opcode_list[i + 1]; | |
1222 | next_op = next->c; | |
1223 | op = list->c; | |
d16005f8 | 1224 | |
03535202 PC |
1225 | if (!has_delay_slot(op) || op_flag_no_ds(list->flags) || |
1226 | op_flag_emulate_branch(list->flags) || | |
98fa08a5 PC |
1227 | op.opcode == 0 || next_op.opcode == 0) |
1228 | continue; | |
1229 | ||
9259d748 | 1230 | if (is_delay_slot(block->opcode_list, i)) |
d16005f8 PC |
1231 | continue; |
1232 | ||
ba3814c1 | 1233 | if (op_flag_sync(next->flags)) |
d16005f8 PC |
1234 | continue; |
1235 | ||
cb72ea13 PC |
1236 | if (op_flag_load_delay(next->flags) && opcode_is_load(next_op)) |
1237 | continue; | |
1238 | ||
ba3814c1 PC |
1239 | if (!lightrec_can_switch_delay_slot(list->c, next_op)) |
1240 | continue; | |
d16005f8 PC |
1241 | |
1242 | pr_debug("Swap branch and delay slot opcodes " | |
98fa08a5 PC |
1243 | "at offsets 0x%x / 0x%x\n", |
1244 | i << 2, (i + 1) << 2); | |
d16005f8 | 1245 | |
ba3814c1 | 1246 | flags = next->flags | (list->flags & LIGHTREC_SYNC); |
d16005f8 | 1247 | list->c = next_op; |
98fa08a5 | 1248 | next->c = op; |
ba3814c1 | 1249 | next->flags = (list->flags | LIGHTREC_NO_DS) & ~LIGHTREC_SYNC; |
a59e5536 | 1250 | list->flags = flags | LIGHTREC_NO_DS; |
d16005f8 PC |
1251 | } |
1252 | ||
1253 | return 0; | |
1254 | } | |
1255 | ||
98fa08a5 PC |
1256 | static int lightrec_detect_impossible_branches(struct lightrec_state *state, |
1257 | struct block *block) | |
d16005f8 | 1258 | { |
03535202 | 1259 | struct opcode *op, *list = block->opcode_list, *next = &list[0]; |
98fa08a5 PC |
1260 | unsigned int i; |
1261 | int ret = 0; | |
1262 | ||
1263 | for (i = 0; i < block->nb_ops - 1; i++) { | |
1264 | op = next; | |
03535202 | 1265 | next = &list[i + 1]; |
d16005f8 | 1266 | |
d16005f8 | 1267 | if (!has_delay_slot(op->c) || |
cb72ea13 PC |
1268 | (!has_delay_slot(next->c) && |
1269 | !opcode_is_mfc(next->c) && | |
d16005f8 PC |
1270 | !(next->i.op == OP_CP0 && next->r.rs == OP_CP0_RFE))) |
1271 | continue; | |
1272 | ||
1273 | if (op->c.opcode == next->c.opcode) { | |
1274 | /* The delay slot is the exact same opcode as the branch | |
1275 | * opcode: this is effectively a NOP */ | |
1276 | next->c.opcode = 0; | |
1277 | continue; | |
1278 | } | |
1279 | ||
cb72ea13 PC |
1280 | op->flags |= LIGHTREC_EMULATE_BRANCH; |
1281 | ||
1282 | if (OPT_LOCAL_BRANCHES && i + 2 < block->nb_ops) { | |
1283 | /* The interpreter will only emulate the branch, then | |
1284 | * return to the compiled code. Add a SYNC after the | |
1285 | * branch + delay slot in the case where the branch | |
1286 | * was not taken. */ | |
1287 | list[i + 2].flags |= LIGHTREC_SYNC; | |
1288 | } | |
1289 | } | |
1290 | ||
1291 | return ret; | |
1292 | } | |
1293 | ||
1294 | static bool is_local_branch(const struct block *block, unsigned int idx) | |
1295 | { | |
1296 | const struct opcode *op = &block->opcode_list[idx]; | |
1297 | s32 offset; | |
1298 | ||
1299 | switch (op->c.i.op) { | |
1300 | case OP_BEQ: | |
1301 | case OP_BNE: | |
1302 | case OP_BLEZ: | |
1303 | case OP_BGTZ: | |
1304 | case OP_REGIMM: | |
1305 | offset = idx + 1 + (s16)op->c.i.imm; | |
1306 | if (offset >= 0 && offset < block->nb_ops) | |
1307 | return true; | |
1308 | fallthrough; | |
1309 | default: | |
1310 | return false; | |
1311 | } | |
1312 | } | |
1313 | ||
1314 | static int lightrec_handle_load_delays(struct lightrec_state *state, | |
1315 | struct block *block) | |
1316 | { | |
1317 | struct opcode *op, *list = block->opcode_list; | |
1318 | unsigned int i; | |
1319 | s16 imm; | |
1320 | ||
1321 | for (i = 0; i < block->nb_ops; i++) { | |
1322 | op = &list[i]; | |
1323 | ||
1324 | if (!opcode_is_load(op->c) || !op->c.i.rt || op->c.i.op == OP_LWC2) | |
1325 | continue; | |
1326 | ||
1327 | if (!is_delay_slot(list, i)) { | |
1328 | /* Only handle load delays in delay slots. | |
1329 | * PSX games never abused load delay slots otherwise. */ | |
03535202 PC |
1330 | continue; |
1331 | } | |
1332 | ||
cb72ea13 PC |
1333 | if (is_local_branch(block, i - 1)) { |
1334 | imm = (s16)list[i - 1].c.i.imm; | |
98fa08a5 | 1335 | |
cb72ea13 PC |
1336 | if (!opcode_reads_register(list[i + imm].c, op->c.i.rt)) { |
1337 | /* The target opcode of the branch is inside | |
1338 | * the block, and it does not read the register | |
1339 | * written to by the load opcode; we can ignore | |
1340 | * the load delay. */ | |
1341 | continue; | |
1342 | } | |
1343 | } | |
98fa08a5 | 1344 | |
cb72ea13 PC |
1345 | op->flags |= LIGHTREC_LOAD_DELAY; |
1346 | } | |
1347 | ||
1348 | return 0; | |
1349 | } | |
1350 | ||
1351 | static int lightrec_swap_load_delays(struct lightrec_state *state, | |
1352 | struct block *block) | |
1353 | { | |
1354 | unsigned int i; | |
1355 | union code c, next; | |
1356 | bool in_ds = false, skip_next = false; | |
1357 | struct opcode op; | |
1358 | ||
1359 | if (block->nb_ops < 2) | |
1360 | return 0; | |
1361 | ||
1362 | for (i = 0; i < block->nb_ops - 2; i++) { | |
1363 | c = block->opcode_list[i].c; | |
1364 | ||
1365 | if (skip_next) { | |
1366 | skip_next = false; | |
1367 | } else if (!in_ds && opcode_is_load(c) && c.i.op != OP_LWC2) { | |
1368 | next = block->opcode_list[i + 1].c; | |
1369 | ||
2ec79b77 PC |
1370 | switch (next.i.op) { |
1371 | case OP_LWL: | |
1372 | case OP_LWR: | |
1373 | case OP_REGIMM: | |
1374 | case OP_BEQ: | |
1375 | case OP_BNE: | |
1376 | case OP_BLEZ: | |
1377 | case OP_BGTZ: | |
cb72ea13 | 1378 | continue; |
2ec79b77 | 1379 | } |
cb72ea13 PC |
1380 | |
1381 | if (opcode_reads_register(next, c.i.rt) | |
1382 | && !opcode_writes_register(next, c.i.rs)) { | |
1383 | pr_debug("Swapping opcodes at offset 0x%x to " | |
1384 | "respect load delay\n", i << 2); | |
1385 | ||
1386 | op = block->opcode_list[i]; | |
1387 | block->opcode_list[i] = block->opcode_list[i + 1]; | |
1388 | block->opcode_list[i + 1] = op; | |
1389 | skip_next = true; | |
1390 | } | |
d16005f8 | 1391 | } |
cb72ea13 PC |
1392 | |
1393 | in_ds = has_delay_slot(c); | |
d16005f8 PC |
1394 | } |
1395 | ||
cb72ea13 | 1396 | return 0; |
d16005f8 PC |
1397 | } |
1398 | ||
98fa08a5 | 1399 | static int lightrec_local_branches(struct lightrec_state *state, struct block *block) |
d16005f8 | 1400 | { |
cb72ea13 | 1401 | const struct opcode *ds; |
98fa08a5 PC |
1402 | struct opcode *list; |
1403 | unsigned int i; | |
d16005f8 | 1404 | s32 offset; |
d16005f8 | 1405 | |
98fa08a5 PC |
1406 | for (i = 0; i < block->nb_ops; i++) { |
1407 | list = &block->opcode_list[i]; | |
1408 | ||
cb72ea13 | 1409 | if (should_emulate(list) || !is_local_branch(block, i)) |
d16005f8 PC |
1410 | continue; |
1411 | ||
cb72ea13 | 1412 | offset = i + 1 + (s16)list->c.i.imm; |
d16005f8 PC |
1413 | |
1414 | pr_debug("Found local branch to offset 0x%x\n", offset << 2); | |
1415 | ||
cb72ea13 PC |
1416 | ds = get_delay_slot(block->opcode_list, i); |
1417 | if (op_flag_load_delay(ds->flags) && opcode_is_load(ds->c)) { | |
1418 | pr_debug("Branch delay slot has a load delay - skip\n"); | |
1419 | continue; | |
1420 | } | |
1421 | ||
98fa08a5 PC |
1422 | if (should_emulate(&block->opcode_list[offset])) { |
1423 | pr_debug("Branch target must be emulated - skip\n"); | |
1424 | continue; | |
1425 | } | |
d16005f8 | 1426 | |
98fa08a5 PC |
1427 | if (offset && has_delay_slot(block->opcode_list[offset - 1].c)) { |
1428 | pr_debug("Branch target is a delay slot - skip\n"); | |
1429 | continue; | |
1430 | } | |
d16005f8 | 1431 | |
98fa08a5 | 1432 | list->flags |= LIGHTREC_LOCAL_BRANCH; |
d16005f8 PC |
1433 | } |
1434 | ||
9259d748 PC |
1435 | lightrec_reset_syncs(block); |
1436 | ||
d16005f8 PC |
1437 | return 0; |
1438 | } | |
1439 | ||
1440 | bool has_delay_slot(union code op) | |
1441 | { | |
1442 | switch (op.i.op) { | |
1443 | case OP_SPECIAL: | |
1444 | switch (op.r.op) { | |
1445 | case OP_SPECIAL_JR: | |
1446 | case OP_SPECIAL_JALR: | |
1447 | return true; | |
1448 | default: | |
1449 | return false; | |
1450 | } | |
1451 | case OP_J: | |
1452 | case OP_JAL: | |
1453 | case OP_BEQ: | |
1454 | case OP_BNE: | |
1455 | case OP_BLEZ: | |
1456 | case OP_BGTZ: | |
1457 | case OP_REGIMM: | |
d16005f8 PC |
1458 | return true; |
1459 | default: | |
1460 | return false; | |
1461 | } | |
1462 | } | |
1463 | ||
9259d748 PC |
1464 | bool is_delay_slot(const struct opcode *list, unsigned int offset) |
1465 | { | |
1466 | return offset > 0 | |
1467 | && !op_flag_no_ds(list[offset - 1].flags) | |
1468 | && has_delay_slot(list[offset - 1].c); | |
1469 | } | |
1470 | ||
98fa08a5 | 1471 | bool should_emulate(const struct opcode *list) |
d16005f8 | 1472 | { |
03535202 PC |
1473 | return op_flag_emulate_branch(list->flags) && has_delay_slot(list->c); |
1474 | } | |
1475 | ||
1476 | static bool op_writes_rd(union code c) | |
1477 | { | |
1478 | switch (c.i.op) { | |
1479 | case OP_SPECIAL: | |
cb72ea13 | 1480 | case OP_META: |
03535202 PC |
1481 | return true; |
1482 | default: | |
1483 | return false; | |
1484 | } | |
1485 | } | |
1486 | ||
1487 | static void lightrec_add_reg_op(struct opcode *op, u8 reg, u32 reg_op) | |
1488 | { | |
1489 | if (op_writes_rd(op->c) && reg == op->r.rd) | |
1490 | op->flags |= LIGHTREC_REG_RD(reg_op); | |
1491 | else if (op->i.rs == reg) | |
1492 | op->flags |= LIGHTREC_REG_RS(reg_op); | |
1493 | else if (op->i.rt == reg) | |
1494 | op->flags |= LIGHTREC_REG_RT(reg_op); | |
1495 | else | |
1496 | pr_debug("Cannot add unload/clean/discard flag: " | |
1497 | "opcode does not touch register %s!\n", | |
1498 | lightrec_reg_name(reg)); | |
d16005f8 PC |
1499 | } |
1500 | ||
98fa08a5 | 1501 | static void lightrec_add_unload(struct opcode *op, u8 reg) |
d16005f8 | 1502 | { |
03535202 PC |
1503 | lightrec_add_reg_op(op, reg, LIGHTREC_REG_UNLOAD); |
1504 | } | |
d16005f8 | 1505 | |
03535202 PC |
1506 | static void lightrec_add_discard(struct opcode *op, u8 reg) |
1507 | { | |
1508 | lightrec_add_reg_op(op, reg, LIGHTREC_REG_DISCARD); | |
1509 | } | |
1510 | ||
1511 | static void lightrec_add_clean(struct opcode *op, u8 reg) | |
1512 | { | |
1513 | lightrec_add_reg_op(op, reg, LIGHTREC_REG_CLEAN); | |
1514 | } | |
1515 | ||
1516 | static void | |
1517 | lightrec_early_unload_sync(struct opcode *list, s16 *last_r, s16 *last_w) | |
1518 | { | |
1519 | unsigned int reg; | |
1520 | s16 offset; | |
1521 | ||
1522 | for (reg = 0; reg < 34; reg++) { | |
1523 | offset = s16_max(last_w[reg], last_r[reg]); | |
1524 | ||
1525 | if (offset >= 0) | |
1526 | lightrec_add_unload(&list[offset], reg); | |
1527 | } | |
1528 | ||
1529 | memset(last_r, 0xff, sizeof(*last_r) * 34); | |
1530 | memset(last_w, 0xff, sizeof(*last_w) * 34); | |
98fa08a5 | 1531 | } |
d16005f8 | 1532 | |
98fa08a5 PC |
1533 | static int lightrec_early_unload(struct lightrec_state *state, struct block *block) |
1534 | { | |
03535202 | 1535 | u16 i, offset; |
98fa08a5 | 1536 | struct opcode *op; |
03535202 PC |
1537 | s16 last_r[34], last_w[34], last_sync = 0, next_sync = 0; |
1538 | u64 mask_r, mask_w, dirty = 0, loaded = 0; | |
cb72ea13 | 1539 | u8 reg, load_delay_reg = 0; |
d16005f8 | 1540 | |
03535202 PC |
1541 | memset(last_r, 0xff, sizeof(last_r)); |
1542 | memset(last_w, 0xff, sizeof(last_w)); | |
98fa08a5 | 1543 | |
03535202 PC |
1544 | /* |
1545 | * Clean if: | |
1546 | * - the register is dirty, and is read again after a branch opcode | |
1547 | * | |
1548 | * Unload if: | |
1549 | * - the register is dirty or loaded, and is not read again | |
1550 | * - the register is dirty or loaded, and is written again after a branch opcode | |
1551 | * - the next opcode has the SYNC flag set | |
1552 | * | |
1553 | * Discard if: | |
1554 | * - the register is dirty or loaded, and is written again | |
1555 | */ | |
98fa08a5 | 1556 | |
03535202 PC |
1557 | for (i = 0; i < block->nb_ops; i++) { |
1558 | op = &block->opcode_list[i]; | |
1559 | ||
cb72ea13 PC |
1560 | if (OPT_HANDLE_LOAD_DELAYS && load_delay_reg) { |
1561 | /* Handle delayed register write from load opcodes in | |
1562 | * delay slots */ | |
1563 | last_w[load_delay_reg] = i; | |
1564 | load_delay_reg = 0; | |
1565 | } | |
1566 | ||
03535202 PC |
1567 | if (op_flag_sync(op->flags) || should_emulate(op)) { |
1568 | /* The next opcode has the SYNC flag set, or is a branch | |
1569 | * that should be emulated: unload all registers. */ | |
1570 | lightrec_early_unload_sync(block->opcode_list, last_r, last_w); | |
1571 | dirty = 0; | |
1572 | loaded = 0; | |
d16005f8 PC |
1573 | } |
1574 | ||
03535202 PC |
1575 | if (next_sync == i) { |
1576 | last_sync = i; | |
1577 | pr_debug("Last sync: 0x%x\n", last_sync << 2); | |
1578 | } | |
d16005f8 | 1579 | |
03535202 PC |
1580 | if (has_delay_slot(op->c)) { |
1581 | next_sync = i + 1 + !op_flag_no_ds(op->flags); | |
1582 | pr_debug("Next sync: 0x%x\n", next_sync << 2); | |
1583 | } | |
d16005f8 | 1584 | |
03535202 PC |
1585 | mask_r = opcode_read_mask(op->c); |
1586 | mask_w = opcode_write_mask(op->c); | |
98fa08a5 | 1587 | |
cb72ea13 PC |
1588 | if (op_flag_load_delay(op->flags) && opcode_is_load(op->c)) { |
1589 | /* If we have a load opcode in a delay slot, its target | |
1590 | * register is actually not written there but at a | |
1591 | * later point, in the dispatcher. Prevent the algorithm | |
1592 | * from discarding its previous value. */ | |
1593 | load_delay_reg = op->c.i.rt; | |
1594 | mask_w &= ~BIT(op->c.i.rt); | |
1595 | } | |
1596 | ||
03535202 PC |
1597 | for (reg = 0; reg < 34; reg++) { |
1598 | if (mask_r & BIT(reg)) { | |
1599 | if (dirty & BIT(reg) && last_w[reg] < last_sync) { | |
1600 | /* The register is dirty, and is read | |
1601 | * again after a branch: clean it */ | |
1602 | ||
1603 | lightrec_add_clean(&block->opcode_list[last_w[reg]], reg); | |
1604 | dirty &= ~BIT(reg); | |
1605 | loaded |= BIT(reg); | |
1606 | } | |
1607 | ||
1608 | last_r[reg] = i; | |
1609 | } | |
1610 | ||
1611 | if (mask_w & BIT(reg)) { | |
1612 | if ((dirty & BIT(reg) && last_w[reg] < last_sync) || | |
1613 | (loaded & BIT(reg) && last_r[reg] < last_sync)) { | |
1614 | /* The register is dirty or loaded, and | |
1615 | * is written again after a branch: | |
1616 | * unload it */ | |
1617 | ||
1618 | offset = s16_max(last_w[reg], last_r[reg]); | |
1619 | lightrec_add_unload(&block->opcode_list[offset], reg); | |
1620 | dirty &= ~BIT(reg); | |
1621 | loaded &= ~BIT(reg); | |
1622 | } else if (!(mask_r & BIT(reg)) && | |
1623 | ((dirty & BIT(reg) && last_w[reg] > last_sync) || | |
1624 | (loaded & BIT(reg) && last_r[reg] > last_sync))) { | |
1625 | /* The register is dirty or loaded, and | |
1626 | * is written again: discard it */ | |
1627 | ||
1628 | offset = s16_max(last_w[reg], last_r[reg]); | |
1629 | lightrec_add_discard(&block->opcode_list[offset], reg); | |
1630 | dirty &= ~BIT(reg); | |
1631 | loaded &= ~BIT(reg); | |
1632 | } | |
1633 | ||
1634 | last_w[reg] = i; | |
1635 | } | |
98fa08a5 | 1636 | |
03535202 PC |
1637 | } |
1638 | ||
1639 | dirty |= mask_w; | |
1640 | loaded |= mask_r; | |
d16005f8 PC |
1641 | } |
1642 | ||
03535202 PC |
1643 | /* Unload all registers that are dirty or loaded at the end of block. */ |
1644 | lightrec_early_unload_sync(block->opcode_list, last_r, last_w); | |
1645 | ||
d16005f8 PC |
1646 | return 0; |
1647 | } | |
1648 | ||
98fa08a5 | 1649 | static int lightrec_flag_io(struct lightrec_state *state, struct block *block) |
d16005f8 | 1650 | { |
9259d748 | 1651 | struct opcode *list; |
02487de7 | 1652 | enum psx_map psx_map; |
9259d748 | 1653 | struct constprop_data v[32] = LIGHTREC_CONSTPROP_INITIALIZER; |
98fa08a5 | 1654 | unsigned int i; |
02487de7 | 1655 | u32 val, kunseg_val; |
ba3814c1 | 1656 | bool no_mask; |
98fa08a5 PC |
1657 | |
1658 | for (i = 0; i < block->nb_ops; i++) { | |
1659 | list = &block->opcode_list[i]; | |
d16005f8 | 1660 | |
cb72ea13 | 1661 | lightrec_consts_propagate(block, i, v); |
22eee2ac | 1662 | |
d16005f8 PC |
1663 | switch (list->i.op) { |
1664 | case OP_SB: | |
1665 | case OP_SH: | |
1666 | case OP_SW: | |
cb72ea13 PC |
1667 | /* Mark all store operations that target $sp or $gp |
1668 | * as not requiring code invalidation. This is based | |
1669 | * on the heuristic that stores using one of these | |
1670 | * registers as address will never hit a code page. */ | |
1671 | if (list->i.rs >= 28 && list->i.rs <= 29 && | |
1672 | !state->maps[PSX_MAP_KERNEL_USER_RAM].ops) { | |
1673 | pr_debug("Flaging opcode 0x%08x as not requiring invalidation\n", | |
1674 | list->opcode); | |
1675 | list->flags |= LIGHTREC_NO_INVALIDATE; | |
1676 | } | |
98fa08a5 | 1677 | |
cb72ea13 PC |
1678 | /* Detect writes whose destination address is inside the |
1679 | * current block, using constant propagation. When these | |
1680 | * occur, we mark the blocks as not compilable. */ | |
1681 | if (is_known(v, list->i.rs) && | |
1682 | kunseg(v[list->i.rs].value) >= kunseg(block->pc) && | |
1683 | kunseg(v[list->i.rs].value) < (kunseg(block->pc) + block->nb_ops * 4)) { | |
1684 | pr_debug("Self-modifying block detected\n"); | |
1685 | block_set_flags(block, BLOCK_NEVER_COMPILE); | |
1686 | list->flags |= LIGHTREC_SMC; | |
98fa08a5 | 1687 | } |
d8b04acd PC |
1688 | fallthrough; |
1689 | case OP_SWL: | |
98fa08a5 PC |
1690 | case OP_SWR: |
1691 | case OP_SWC2: | |
1692 | case OP_LB: | |
1693 | case OP_LBU: | |
1694 | case OP_LH: | |
1695 | case OP_LHU: | |
1696 | case OP_LW: | |
1697 | case OP_LWL: | |
1698 | case OP_LWR: | |
1699 | case OP_LWC2: | |
cb72ea13 | 1700 | if (v[list->i.rs].known | v[list->i.rs].sign) { |
9259d748 PC |
1701 | psx_map = lightrec_get_constprop_map(state, v, |
1702 | list->i.rs, | |
1703 | (s16) list->i.imm); | |
1704 | ||
1705 | if (psx_map != PSX_MAP_UNKNOWN && !is_known(v, list->i.rs)) | |
1706 | pr_debug("Detected map thanks to bit-level const propagation!\n"); | |
02487de7 | 1707 | |
03535202 | 1708 | list->flags &= ~LIGHTREC_IO_MASK; |
9259d748 PC |
1709 | |
1710 | val = v[list->i.rs].value + (s16) list->i.imm; | |
1711 | kunseg_val = kunseg(val); | |
1712 | ||
1713 | no_mask = (v[list->i.rs].known & ~v[list->i.rs].value | |
1714 | & 0xe0000000) == 0xe0000000; | |
03535202 | 1715 | |
02487de7 PC |
1716 | switch (psx_map) { |
1717 | case PSX_MAP_KERNEL_USER_RAM: | |
ba3814c1 | 1718 | if (no_mask) |
02487de7 | 1719 | list->flags |= LIGHTREC_NO_MASK; |
d8b04acd | 1720 | fallthrough; |
02487de7 PC |
1721 | case PSX_MAP_MIRROR1: |
1722 | case PSX_MAP_MIRROR2: | |
1723 | case PSX_MAP_MIRROR3: | |
22eee2ac PC |
1724 | pr_debug("Flaging opcode %u as RAM access\n", i); |
1725 | list->flags |= LIGHTREC_IO_MODE(LIGHTREC_IO_RAM); | |
ba3814c1 PC |
1726 | if (no_mask && state->mirrors_mapped) |
1727 | list->flags |= LIGHTREC_NO_MASK; | |
02487de7 PC |
1728 | break; |
1729 | case PSX_MAP_BIOS: | |
22eee2ac PC |
1730 | pr_debug("Flaging opcode %u as BIOS access\n", i); |
1731 | list->flags |= LIGHTREC_IO_MODE(LIGHTREC_IO_BIOS); | |
ba3814c1 PC |
1732 | if (no_mask) |
1733 | list->flags |= LIGHTREC_NO_MASK; | |
02487de7 PC |
1734 | break; |
1735 | case PSX_MAP_SCRATCH_PAD: | |
22eee2ac PC |
1736 | pr_debug("Flaging opcode %u as scratchpad access\n", i); |
1737 | list->flags |= LIGHTREC_IO_MODE(LIGHTREC_IO_SCRATCH); | |
ba3814c1 PC |
1738 | if (no_mask) |
1739 | list->flags |= LIGHTREC_NO_MASK; | |
02487de7 PC |
1740 | |
1741 | /* Consider that we're never going to run code from | |
1742 | * the scratchpad. */ | |
1743 | list->flags |= LIGHTREC_NO_INVALIDATE; | |
1744 | break; | |
ba3814c1 PC |
1745 | case PSX_MAP_HW_REGISTERS: |
1746 | if (state->ops.hw_direct && | |
1747 | state->ops.hw_direct(kunseg_val, | |
1748 | opcode_is_store(list->c), | |
1749 | opcode_get_io_size(list->c))) { | |
1750 | pr_debug("Flagging opcode %u as direct I/O access\n", | |
1751 | i); | |
1752 | list->flags |= LIGHTREC_IO_MODE(LIGHTREC_IO_DIRECT_HW); | |
cdfa3536 PC |
1753 | |
1754 | if (no_mask) | |
1755 | list->flags |= LIGHTREC_NO_MASK; | |
9259d748 PC |
1756 | } else { |
1757 | pr_debug("Flagging opcode %u as I/O access\n", | |
1758 | i); | |
1759 | list->flags |= LIGHTREC_IO_MODE(LIGHTREC_IO_HW); | |
ba3814c1 | 1760 | } |
9259d748 | 1761 | break; |
02487de7 | 1762 | default: |
02487de7 | 1763 | break; |
98fa08a5 | 1764 | } |
d16005f8 | 1765 | } |
cb72ea13 PC |
1766 | |
1767 | if (!LIGHTREC_FLAGS_GET_IO_MODE(list->flags) | |
1768 | && list->i.rs >= 28 && list->i.rs <= 29 | |
1769 | && !state->maps[PSX_MAP_KERNEL_USER_RAM].ops) { | |
1770 | /* Assume that all I/O operations that target | |
1771 | * $sp or $gp will always only target a mapped | |
1772 | * memory (RAM, BIOS, scratchpad). */ | |
684432ad PC |
1773 | if (state->opt_flags & LIGHTREC_OPT_SP_GP_HIT_RAM) |
1774 | list->flags |= LIGHTREC_IO_MODE(LIGHTREC_IO_RAM); | |
1775 | else | |
1776 | list->flags |= LIGHTREC_IO_MODE(LIGHTREC_IO_DIRECT); | |
cb72ea13 PC |
1777 | } |
1778 | ||
d8b04acd PC |
1779 | fallthrough; |
1780 | default: | |
d16005f8 PC |
1781 | break; |
1782 | } | |
d16005f8 PC |
1783 | } |
1784 | ||
1785 | return 0; | |
1786 | } | |
1787 | ||
98fa08a5 PC |
1788 | static u8 get_mfhi_mflo_reg(const struct block *block, u16 offset, |
1789 | const struct opcode *last, | |
1790 | u32 mask, bool sync, bool mflo, bool another) | |
d16005f8 | 1791 | { |
98fa08a5 PC |
1792 | const struct opcode *op, *next = &block->opcode_list[offset]; |
1793 | u32 old_mask; | |
1794 | u8 reg2, reg = mflo ? REG_LO : REG_HI; | |
1795 | u16 branch_offset; | |
1796 | unsigned int i; | |
1797 | ||
1798 | for (i = offset; i < block->nb_ops; i++) { | |
1799 | op = next; | |
1800 | next = &block->opcode_list[i + 1]; | |
1801 | old_mask = mask; | |
1802 | ||
1803 | /* If any other opcode writes or reads to the register | |
1804 | * we'd use, then we cannot use it anymore. */ | |
1805 | mask |= opcode_read_mask(op->c); | |
1806 | mask |= opcode_write_mask(op->c); | |
1807 | ||
03535202 | 1808 | if (op_flag_sync(op->flags)) |
98fa08a5 | 1809 | sync = true; |
d16005f8 | 1810 | |
d16005f8 PC |
1811 | switch (op->i.op) { |
1812 | case OP_BEQ: | |
1813 | case OP_BNE: | |
1814 | case OP_BLEZ: | |
1815 | case OP_BGTZ: | |
1816 | case OP_REGIMM: | |
d16005f8 | 1817 | /* TODO: handle backwards branches too */ |
03535202 | 1818 | if (!last && op_flag_local_branch(op->flags) && |
d16005f8 | 1819 | (s16)op->c.i.imm >= 0) { |
98fa08a5 | 1820 | branch_offset = i + 1 + (s16)op->c.i.imm |
03535202 | 1821 | - !!op_flag_no_ds(op->flags); |
98fa08a5 PC |
1822 | |
1823 | reg = get_mfhi_mflo_reg(block, branch_offset, NULL, | |
1824 | mask, sync, mflo, false); | |
1825 | reg2 = get_mfhi_mflo_reg(block, offset + 1, next, | |
1826 | mask, sync, mflo, false); | |
1827 | if (reg > 0 && reg == reg2) | |
1828 | return reg; | |
1829 | if (!reg && !reg2) | |
1830 | return 0; | |
d16005f8 | 1831 | } |
98fa08a5 PC |
1832 | |
1833 | return mflo ? REG_LO : REG_HI; | |
ba3814c1 PC |
1834 | case OP_META_MULT2: |
1835 | case OP_META_MULTU2: | |
1836 | return 0; | |
d16005f8 PC |
1837 | case OP_SPECIAL: |
1838 | switch (op->r.op) { | |
1839 | case OP_SPECIAL_MULT: | |
1840 | case OP_SPECIAL_MULTU: | |
1841 | case OP_SPECIAL_DIV: | |
1842 | case OP_SPECIAL_DIVU: | |
98fa08a5 | 1843 | return 0; |
d16005f8 | 1844 | case OP_SPECIAL_MTHI: |
98fa08a5 PC |
1845 | if (!mflo) |
1846 | return 0; | |
1847 | continue; | |
1848 | case OP_SPECIAL_MTLO: | |
1849 | if (mflo) | |
1850 | return 0; | |
1851 | continue; | |
d16005f8 | 1852 | case OP_SPECIAL_JR: |
98fa08a5 PC |
1853 | if (op->r.rs != 31) |
1854 | return reg; | |
1855 | ||
03535202 | 1856 | if (!sync && !op_flag_no_ds(op->flags) && |
98fa08a5 PC |
1857 | (next->i.op == OP_SPECIAL) && |
1858 | ((!mflo && next->r.op == OP_SPECIAL_MFHI) || | |
1859 | (mflo && next->r.op == OP_SPECIAL_MFLO))) | |
1860 | return next->r.rd; | |
1861 | ||
1862 | return 0; | |
d16005f8 | 1863 | case OP_SPECIAL_JALR: |
98fa08a5 | 1864 | return reg; |
d16005f8 | 1865 | case OP_SPECIAL_MFHI: |
98fa08a5 PC |
1866 | if (!mflo) { |
1867 | if (another) | |
1868 | return op->r.rd; | |
1869 | /* Must use REG_HI if there is another MFHI target*/ | |
1870 | reg2 = get_mfhi_mflo_reg(block, i + 1, next, | |
1871 | 0, sync, mflo, true); | |
1872 | if (reg2 > 0 && reg2 != REG_HI) | |
1873 | return REG_HI; | |
1874 | ||
1875 | if (!sync && !(old_mask & BIT(op->r.rd))) | |
1876 | return op->r.rd; | |
1877 | else | |
1878 | return REG_HI; | |
1879 | } | |
1880 | continue; | |
1881 | case OP_SPECIAL_MFLO: | |
1882 | if (mflo) { | |
1883 | if (another) | |
1884 | return op->r.rd; | |
1885 | /* Must use REG_LO if there is another MFLO target*/ | |
1886 | reg2 = get_mfhi_mflo_reg(block, i + 1, next, | |
1887 | 0, sync, mflo, true); | |
1888 | if (reg2 > 0 && reg2 != REG_LO) | |
1889 | return REG_LO; | |
1890 | ||
1891 | if (!sync && !(old_mask & BIT(op->r.rd))) | |
1892 | return op->r.rd; | |
1893 | else | |
1894 | return REG_LO; | |
1895 | } | |
d16005f8 | 1896 | continue; |
98fa08a5 PC |
1897 | default: |
1898 | break; | |
d16005f8 | 1899 | } |
98fa08a5 | 1900 | |
d8b04acd | 1901 | fallthrough; |
d16005f8 PC |
1902 | default: |
1903 | continue; | |
1904 | } | |
1905 | } | |
1906 | ||
98fa08a5 PC |
1907 | return reg; |
1908 | } | |
1909 | ||
1910 | static void lightrec_replace_lo_hi(struct block *block, u16 offset, | |
1911 | u16 last, bool lo) | |
1912 | { | |
1913 | unsigned int i; | |
1914 | u32 branch_offset; | |
1915 | ||
1916 | /* This function will remove the following MFLO/MFHI. It must be called | |
1917 | * only if get_mfhi_mflo_reg() returned a non-zero value. */ | |
1918 | ||
1919 | for (i = offset; i < last; i++) { | |
1920 | struct opcode *op = &block->opcode_list[i]; | |
1921 | ||
1922 | switch (op->i.op) { | |
1923 | case OP_BEQ: | |
1924 | case OP_BNE: | |
1925 | case OP_BLEZ: | |
1926 | case OP_BGTZ: | |
1927 | case OP_REGIMM: | |
1928 | /* TODO: handle backwards branches too */ | |
03535202 | 1929 | if (op_flag_local_branch(op->flags) && (s16)op->c.i.imm >= 0) { |
98fa08a5 | 1930 | branch_offset = i + 1 + (s16)op->c.i.imm |
03535202 | 1931 | - !!op_flag_no_ds(op->flags); |
98fa08a5 PC |
1932 | |
1933 | lightrec_replace_lo_hi(block, branch_offset, last, lo); | |
1934 | lightrec_replace_lo_hi(block, i + 1, branch_offset, lo); | |
1935 | } | |
1936 | break; | |
1937 | ||
1938 | case OP_SPECIAL: | |
1939 | if (lo && op->r.op == OP_SPECIAL_MFLO) { | |
1940 | pr_debug("Removing MFLO opcode at offset 0x%x\n", | |
1941 | i << 2); | |
1942 | op->opcode = 0; | |
1943 | return; | |
1944 | } else if (!lo && op->r.op == OP_SPECIAL_MFHI) { | |
1945 | pr_debug("Removing MFHI opcode at offset 0x%x\n", | |
1946 | i << 2); | |
1947 | op->opcode = 0; | |
1948 | return; | |
1949 | } | |
1950 | ||
d8b04acd | 1951 | fallthrough; |
98fa08a5 PC |
1952 | default: |
1953 | break; | |
1954 | } | |
1955 | } | |
d16005f8 PC |
1956 | } |
1957 | ||
fd58fa32 PC |
1958 | static bool lightrec_always_skip_div_check(void) |
1959 | { | |
1960 | #ifdef __mips__ | |
1961 | return true; | |
1962 | #else | |
1963 | return false; | |
1964 | #endif | |
1965 | } | |
1966 | ||
98fa08a5 | 1967 | static int lightrec_flag_mults_divs(struct lightrec_state *state, struct block *block) |
d16005f8 | 1968 | { |
9259d748 PC |
1969 | struct opcode *list = NULL; |
1970 | struct constprop_data v[32] = LIGHTREC_CONSTPROP_INITIALIZER; | |
98fa08a5 PC |
1971 | u8 reg_hi, reg_lo; |
1972 | unsigned int i; | |
1973 | ||
1974 | for (i = 0; i < block->nb_ops - 1; i++) { | |
1975 | list = &block->opcode_list[i]; | |
d16005f8 | 1976 | |
cb72ea13 | 1977 | lightrec_consts_propagate(block, i, v); |
22eee2ac | 1978 | |
ba3814c1 PC |
1979 | switch (list->i.op) { |
1980 | case OP_SPECIAL: | |
1981 | switch (list->r.op) { | |
1982 | case OP_SPECIAL_DIV: | |
1983 | case OP_SPECIAL_DIVU: | |
1984 | /* If we are dividing by a non-zero constant, don't | |
1985 | * emit the div-by-zero check. */ | |
1986 | if (lightrec_always_skip_div_check() || | |
9259d748 | 1987 | (v[list->r.rt].known & v[list->r.rt].value)) { |
ba3814c1 | 1988 | list->flags |= LIGHTREC_NO_DIV_CHECK; |
9259d748 | 1989 | } |
ba3814c1 PC |
1990 | fallthrough; |
1991 | case OP_SPECIAL_MULT: | |
1992 | case OP_SPECIAL_MULTU: | |
1993 | break; | |
1994 | default: | |
1995 | continue; | |
1996 | } | |
d8b04acd | 1997 | fallthrough; |
ba3814c1 PC |
1998 | case OP_META_MULT2: |
1999 | case OP_META_MULTU2: | |
d16005f8 PC |
2000 | break; |
2001 | default: | |
2002 | continue; | |
2003 | } | |
2004 | ||
98fa08a5 | 2005 | /* Don't support opcodes in delay slots */ |
9259d748 | 2006 | if (is_delay_slot(block->opcode_list, i) || |
03535202 | 2007 | op_flag_no_ds(list->flags)) { |
d16005f8 | 2008 | continue; |
fd58fa32 | 2009 | } |
d16005f8 | 2010 | |
98fa08a5 PC |
2011 | reg_lo = get_mfhi_mflo_reg(block, i + 1, NULL, 0, false, true, false); |
2012 | if (reg_lo == 0) { | |
2013 | pr_debug("Mark MULT(U)/DIV(U) opcode at offset 0x%x as" | |
2014 | " not writing LO\n", i << 2); | |
2015 | list->flags |= LIGHTREC_NO_LO; | |
2016 | } | |
2017 | ||
2018 | reg_hi = get_mfhi_mflo_reg(block, i + 1, NULL, 0, false, false, false); | |
2019 | if (reg_hi == 0) { | |
2020 | pr_debug("Mark MULT(U)/DIV(U) opcode at offset 0x%x as" | |
2021 | " not writing HI\n", i << 2); | |
2022 | list->flags |= LIGHTREC_NO_HI; | |
2023 | } | |
2024 | ||
2025 | if (!reg_lo && !reg_hi) { | |
2026 | pr_debug("Both LO/HI unused in this block, they will " | |
2027 | "probably be used in parent block - removing " | |
2028 | "flags.\n"); | |
2029 | list->flags &= ~(LIGHTREC_NO_LO | LIGHTREC_NO_HI); | |
2030 | } | |
2031 | ||
2032 | if (reg_lo > 0 && reg_lo != REG_LO) { | |
2033 | pr_debug("Found register %s to hold LO (rs = %u, rt = %u)\n", | |
2034 | lightrec_reg_name(reg_lo), list->r.rs, list->r.rt); | |
2035 | ||
2036 | lightrec_replace_lo_hi(block, i + 1, block->nb_ops, true); | |
2037 | list->r.rd = reg_lo; | |
2038 | } else { | |
2039 | list->r.rd = 0; | |
2040 | } | |
2041 | ||
2042 | if (reg_hi > 0 && reg_hi != REG_HI) { | |
2043 | pr_debug("Found register %s to hold HI (rs = %u, rt = %u)\n", | |
2044 | lightrec_reg_name(reg_hi), list->r.rs, list->r.rt); | |
2045 | ||
2046 | lightrec_replace_lo_hi(block, i + 1, block->nb_ops, false); | |
2047 | list->r.imm = reg_hi; | |
2048 | } else { | |
2049 | list->r.imm = 0; | |
2050 | } | |
2051 | } | |
2052 | ||
2053 | return 0; | |
2054 | } | |
2055 | ||
2056 | static bool remove_div_sequence(struct block *block, unsigned int offset) | |
2057 | { | |
2058 | struct opcode *op; | |
2059 | unsigned int i, found = 0; | |
2060 | ||
2061 | /* | |
2062 | * Scan for the zero-checking sequence that GCC automatically introduced | |
2063 | * after most DIV/DIVU opcodes. This sequence checks the value of the | |
2064 | * divisor, and if zero, executes a BREAK opcode, causing the BIOS | |
2065 | * handler to crash the PS1. | |
2066 | * | |
2067 | * For DIV opcodes, this sequence additionally checks that the signed | |
2068 | * operation does not overflow. | |
2069 | * | |
2070 | * With the assumption that the games never crashed the PS1, we can | |
2071 | * therefore assume that the games never divided by zero or overflowed, | |
2072 | * and these sequences can be removed. | |
2073 | */ | |
2074 | ||
2075 | for (i = offset; i < block->nb_ops; i++) { | |
2076 | op = &block->opcode_list[i]; | |
2077 | ||
2078 | if (!found) { | |
2079 | if (op->i.op == OP_SPECIAL && | |
2080 | (op->r.op == OP_SPECIAL_DIV || op->r.op == OP_SPECIAL_DIVU)) | |
2081 | break; | |
2082 | ||
2083 | if ((op->opcode & 0xfc1fffff) == 0x14000002) { | |
2084 | /* BNE ???, zero, +8 */ | |
2085 | found++; | |
2086 | } else { | |
2087 | offset++; | |
2088 | } | |
2089 | } else if (found == 1 && !op->opcode) { | |
2090 | /* NOP */ | |
2091 | found++; | |
2092 | } else if (found == 2 && op->opcode == 0x0007000d) { | |
2093 | /* BREAK 0x1c00 */ | |
2094 | found++; | |
2095 | } else if (found == 3 && op->opcode == 0x2401ffff) { | |
2096 | /* LI at, -1 */ | |
2097 | found++; | |
2098 | } else if (found == 4 && (op->opcode & 0xfc1fffff) == 0x14010004) { | |
2099 | /* BNE ???, at, +16 */ | |
2100 | found++; | |
2101 | } else if (found == 5 && op->opcode == 0x3c018000) { | |
2102 | /* LUI at, 0x8000 */ | |
2103 | found++; | |
2104 | } else if (found == 6 && (op->opcode & 0x141fffff) == 0x14010002) { | |
2105 | /* BNE ???, at, +16 */ | |
2106 | found++; | |
2107 | } else if (found == 7 && !op->opcode) { | |
2108 | /* NOP */ | |
2109 | found++; | |
2110 | } else if (found == 8 && op->opcode == 0x0006000d) { | |
2111 | /* BREAK 0x1800 */ | |
2112 | found++; | |
2113 | break; | |
2114 | } else { | |
2115 | break; | |
2116 | } | |
2117 | } | |
2118 | ||
2119 | if (found >= 3) { | |
2120 | if (found != 9) | |
2121 | found = 3; | |
2122 | ||
2123 | pr_debug("Removing DIV%s sequence at offset 0x%x\n", | |
2124 | found == 9 ? "" : "U", offset << 2); | |
2125 | ||
2126 | for (i = 0; i < found; i++) | |
2127 | block->opcode_list[offset + i].opcode = 0; | |
2128 | ||
2129 | return true; | |
2130 | } | |
2131 | ||
2132 | return false; | |
2133 | } | |
2134 | ||
2135 | static int lightrec_remove_div_by_zero_check_sequence(struct lightrec_state *state, | |
2136 | struct block *block) | |
2137 | { | |
2138 | struct opcode *op; | |
2139 | unsigned int i; | |
2140 | ||
2141 | for (i = 0; i < block->nb_ops; i++) { | |
2142 | op = &block->opcode_list[i]; | |
2143 | ||
2144 | if (op->i.op == OP_SPECIAL && | |
2145 | (op->r.op == OP_SPECIAL_DIVU || op->r.op == OP_SPECIAL_DIV) && | |
2146 | remove_div_sequence(block, i + 1)) | |
2147 | op->flags |= LIGHTREC_NO_DIV_CHECK; | |
2148 | } | |
2149 | ||
2150 | return 0; | |
2151 | } | |
2152 | ||
2153 | static const u32 memset_code[] = { | |
2154 | 0x10a00006, // beqz a1, 2f | |
2155 | 0x24a2ffff, // addiu v0,a1,-1 | |
2156 | 0x2403ffff, // li v1,-1 | |
2157 | 0xac800000, // 1: sw zero,0(a0) | |
2158 | 0x2442ffff, // addiu v0,v0,-1 | |
2159 | 0x1443fffd, // bne v0,v1, 1b | |
2160 | 0x24840004, // addiu a0,a0,4 | |
2161 | 0x03e00008, // 2: jr ra | |
2162 | 0x00000000, // nop | |
2163 | }; | |
2164 | ||
2165 | static int lightrec_replace_memset(struct lightrec_state *state, struct block *block) | |
2166 | { | |
2167 | unsigned int i; | |
2168 | union code c; | |
2169 | ||
2170 | for (i = 0; i < block->nb_ops; i++) { | |
2171 | c = block->opcode_list[i].c; | |
2172 | ||
2173 | if (c.opcode != memset_code[i]) | |
2174 | return 0; | |
2175 | ||
2176 | if (i == ARRAY_SIZE(memset_code) - 1) { | |
2177 | /* success! */ | |
2178 | pr_debug("Block at PC 0x%x is a memset\n", block->pc); | |
ba3814c1 PC |
2179 | block_set_flags(block, |
2180 | BLOCK_IS_MEMSET | BLOCK_NEVER_COMPILE); | |
98fa08a5 PC |
2181 | |
2182 | /* Return non-zero to skip other optimizers. */ | |
2183 | return 1; | |
d16005f8 PC |
2184 | } |
2185 | } | |
2186 | ||
2187 | return 0; | |
2188 | } | |
2189 | ||
684432ad PC |
2190 | static int lightrec_test_preload_pc(struct lightrec_state *state, struct block *block) |
2191 | { | |
2192 | unsigned int i; | |
2193 | union code c; | |
2194 | u32 flags; | |
2195 | ||
2196 | for (i = 0; i < block->nb_ops; i++) { | |
2197 | c = block->opcode_list[i].c; | |
2198 | flags = block->opcode_list[i].flags; | |
2199 | ||
2200 | if (op_flag_sync(flags)) | |
2201 | break; | |
2202 | ||
2203 | switch (c.i.op) { | |
2204 | case OP_J: | |
2205 | case OP_JAL: | |
2206 | block->flags |= BLOCK_PRELOAD_PC; | |
2207 | return 0; | |
2208 | ||
2209 | case OP_REGIMM: | |
2210 | switch (c.r.rt) { | |
2211 | case OP_REGIMM_BLTZAL: | |
2212 | case OP_REGIMM_BGEZAL: | |
2213 | block->flags |= BLOCK_PRELOAD_PC; | |
2214 | return 0; | |
2215 | default: | |
2216 | break; | |
2217 | } | |
2218 | fallthrough; | |
2219 | case OP_BEQ: | |
2220 | case OP_BNE: | |
2221 | case OP_BLEZ: | |
2222 | case OP_BGTZ: | |
2223 | if (!op_flag_local_branch(flags)) { | |
2224 | block->flags |= BLOCK_PRELOAD_PC; | |
2225 | return 0; | |
2226 | } | |
2227 | ||
2228 | case OP_SPECIAL: | |
2229 | switch (c.r.op) { | |
2230 | case OP_SPECIAL_JALR: | |
2231 | if (c.r.rd) { | |
2232 | block->flags |= BLOCK_PRELOAD_PC; | |
2233 | return 0; | |
2234 | } | |
2235 | break; | |
2236 | case OP_SPECIAL_SYSCALL: | |
2237 | case OP_SPECIAL_BREAK: | |
2238 | block->flags |= BLOCK_PRELOAD_PC; | |
2239 | return 0; | |
2240 | default: | |
2241 | break; | |
2242 | } | |
2243 | break; | |
2244 | } | |
2245 | } | |
2246 | ||
2247 | return 0; | |
2248 | } | |
2249 | ||
98fa08a5 PC |
2250 | static int (*lightrec_optimizers[])(struct lightrec_state *state, struct block *) = { |
2251 | IF_OPT(OPT_REMOVE_DIV_BY_ZERO_SEQ, &lightrec_remove_div_by_zero_check_sequence), | |
2252 | IF_OPT(OPT_REPLACE_MEMSET, &lightrec_replace_memset), | |
2253 | IF_OPT(OPT_DETECT_IMPOSSIBLE_BRANCHES, &lightrec_detect_impossible_branches), | |
cb72ea13 PC |
2254 | IF_OPT(OPT_HANDLE_LOAD_DELAYS, &lightrec_handle_load_delays), |
2255 | IF_OPT(OPT_HANDLE_LOAD_DELAYS, &lightrec_swap_load_delays), | |
03535202 | 2256 | IF_OPT(OPT_TRANSFORM_OPS, &lightrec_transform_branches), |
98fa08a5 PC |
2257 | IF_OPT(OPT_LOCAL_BRANCHES, &lightrec_local_branches), |
2258 | IF_OPT(OPT_TRANSFORM_OPS, &lightrec_transform_ops), | |
2259 | IF_OPT(OPT_SWITCH_DELAY_SLOTS, &lightrec_switch_delay_slots), | |
cb72ea13 | 2260 | IF_OPT(OPT_FLAG_IO, &lightrec_flag_io), |
98fa08a5 PC |
2261 | IF_OPT(OPT_FLAG_MULT_DIV, &lightrec_flag_mults_divs), |
2262 | IF_OPT(OPT_EARLY_UNLOAD, &lightrec_early_unload), | |
684432ad | 2263 | IF_OPT(OPT_PRELOAD_PC, &lightrec_test_preload_pc), |
d16005f8 PC |
2264 | }; |
2265 | ||
98fa08a5 | 2266 | int lightrec_optimize(struct lightrec_state *state, struct block *block) |
d16005f8 PC |
2267 | { |
2268 | unsigned int i; | |
98fa08a5 | 2269 | int ret; |
d16005f8 PC |
2270 | |
2271 | for (i = 0; i < ARRAY_SIZE(lightrec_optimizers); i++) { | |
98fa08a5 PC |
2272 | if (lightrec_optimizers[i]) { |
2273 | ret = (*lightrec_optimizers[i])(state, block); | |
2274 | if (ret) | |
2275 | return ret; | |
2276 | } | |
d16005f8 PC |
2277 | } |
2278 | ||
2279 | return 0; | |
2280 | } |