]>
Commit | Line | Data |
---|---|---|
32f30c53 | 1 | /* Generate code from machine description to perform peephole optimizations. |
ae90e6a3 | 2 | Copyright (C) 1987, 1989, 1992 Free Software Foundation, Inc. |
32f30c53 TW |
3 | |
4 | This file is part of GNU CC. | |
5 | ||
6 | GNU CC is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 2, or (at your option) | |
9 | any later version. | |
10 | ||
11 | GNU CC is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GNU CC; see the file COPYING. If not, write to | |
18 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
19 | ||
20 | ||
21 | #include <stdio.h> | |
22 | #include "config.h" | |
23 | #include "rtl.h" | |
24 | #include "obstack.h" | |
25 | ||
26 | static struct obstack obstack; | |
27 | struct obstack *rtl_obstack = &obstack; | |
28 | ||
29 | #define obstack_chunk_alloc xmalloc | |
30 | #define obstack_chunk_free free | |
31 | ||
32 | extern void free (); | |
33 | ||
34 | /* While tree-walking an instruction pattern, we keep a chain | |
35 | of these `struct link's to record how to get down to the | |
36 | current position. In each one, POS is the operand number, | |
37 | and if the operand is a vector VEC is the element number. | |
38 | VEC is -1 if the operand is not a vector. */ | |
39 | ||
40 | struct link | |
41 | { | |
42 | struct link *next; | |
43 | int pos; | |
44 | int vecelt; | |
45 | }; | |
46 | ||
47 | char *xmalloc (); | |
48 | static void match_rtx (); | |
49 | static void gen_exp (); | |
50 | static void fatal (); | |
51 | void fancy_abort (); | |
52 | ||
53 | static int max_opno; | |
54 | ||
55 | /* Number of operands used in current peephole definition. */ | |
56 | ||
57 | static int n_operands; | |
58 | ||
59 | /* Peephole optimizations get insn codes just like insn patterns. | |
60 | Count them so we know the code of the define_peephole we are handling. */ | |
61 | ||
62 | static int insn_code_number = 0; | |
63 | ||
64 | static void print_path (); | |
65 | static void print_code (); | |
66 | \f | |
67 | static void | |
68 | gen_peephole (peep) | |
69 | rtx peep; | |
70 | { | |
71 | int ninsns = XVECLEN (peep, 0); | |
72 | int i; | |
73 | ||
74 | n_operands = 0; | |
75 | ||
76 | printf (" insn = ins1;\n"); | |
77 | #if 0 | |
78 | printf (" want_jump = 0;\n"); | |
79 | #endif | |
80 | ||
81 | for (i = 0; i < ninsns; i++) | |
82 | { | |
83 | if (i > 0) | |
84 | { | |
85 | printf (" do { insn = NEXT_INSN (insn);\n"); | |
86 | printf (" if (insn == 0) goto L%d; }\n", | |
87 | insn_code_number); | |
88 | printf (" while (GET_CODE (insn) == NOTE\n"); | |
89 | printf ("\t || (GET_CODE (insn) == INSN\n"); | |
90 | printf ("\t && (GET_CODE (PATTERN (insn)) == USE\n"); | |
91 | printf ("\t\t || GET_CODE (PATTERN (insn)) == CLOBBER)));\n"); | |
92 | ||
93 | printf (" if (GET_CODE (insn) == CODE_LABEL\n\ | |
94 | || GET_CODE (insn) == BARRIER)\n goto L%d;\n", | |
95 | insn_code_number); | |
96 | } | |
97 | ||
98 | #if 0 | |
99 | printf (" if (GET_CODE (insn) == JUMP_INSN)\n"); | |
100 | printf (" want_jump = JUMP_LABEL (insn);\n"); | |
101 | #endif | |
102 | ||
103 | printf (" pat = PATTERN (insn);\n"); | |
104 | ||
105 | /* Walk the insn's pattern, remembering at all times the path | |
106 | down to the walking point. */ | |
107 | ||
108 | match_rtx (XVECEXP (peep, 0, i), 0, insn_code_number); | |
109 | } | |
110 | ||
111 | /* We get this far if the pattern matches. | |
112 | Now test the extra condition. */ | |
113 | ||
114 | if (XSTR (peep, 1) && XSTR (peep, 1)[0]) | |
115 | printf (" if (! (%s)) goto L%d;\n", | |
116 | XSTR (peep, 1), insn_code_number); | |
117 | ||
118 | /* If that matches, construct new pattern and put it in the first insn. | |
119 | This new pattern will never be matched. | |
120 | It exists only so that insn-extract can get the operands back. | |
121 | So use a simple regular form: a PARALLEL containing a vector | |
122 | of all the operands. */ | |
123 | ||
124 | printf (" PATTERN (ins1) = gen_rtx (PARALLEL, VOIDmode, gen_rtvec_v (%d, operands));\n", n_operands); | |
125 | ||
126 | #if 0 | |
127 | printf (" if (want_jump && GET_CODE (ins1) != JUMP_INSN)\n"); | |
128 | printf (" {\n"); | |
129 | printf (" rtx insn2 = emit_jump_insn_before (PATTERN (ins1), ins1);\n"); | |
130 | printf (" delete_insn (ins1);\n"); | |
131 | printf (" ins1 = ins2;\n"); | |
132 | printf (" }\n"); | |
133 | #endif | |
134 | ||
135 | /* Record this define_peephole's insn code in the insn, | |
136 | as if it had been recognized to match this. */ | |
137 | printf (" INSN_CODE (ins1) = %d;\n", | |
138 | insn_code_number); | |
139 | ||
140 | /* Delete the remaining insns. */ | |
141 | if (ninsns > 1) | |
142 | printf (" delete_for_peephole (NEXT_INSN (ins1), insn);\n"); | |
143 | ||
144 | /* See reload1.c for insertion of NOTE which guarantees that this | |
145 | cannot be zero. */ | |
146 | printf (" return NEXT_INSN (insn);\n"); | |
147 | ||
148 | printf (" L%d:\n\n", insn_code_number); | |
149 | } | |
150 | \f | |
151 | static void | |
152 | match_rtx (x, path, fail_label) | |
153 | rtx x; | |
154 | struct link *path; | |
155 | int fail_label; | |
156 | { | |
157 | register RTX_CODE code; | |
158 | register int i; | |
159 | register int len; | |
160 | register char *fmt; | |
161 | struct link link; | |
162 | ||
163 | if (x == 0) | |
164 | return; | |
165 | ||
166 | ||
167 | code = GET_CODE (x); | |
168 | ||
169 | switch (code) | |
170 | { | |
171 | case MATCH_OPERAND: | |
172 | if (XINT (x, 0) > max_opno) | |
173 | max_opno = XINT (x, 0); | |
174 | if (XINT (x, 0) >= n_operands) | |
175 | n_operands = 1 + XINT (x, 0); | |
176 | ||
177 | printf (" x = "); | |
178 | print_path (path); | |
179 | printf (";\n"); | |
180 | ||
181 | printf (" operands[%d] = x;\n", XINT (x, 0)); | |
182 | if (XSTR (x, 1) && XSTR (x, 1)[0]) | |
183 | printf (" if (! %s (x, %smode)) goto L%d;\n", | |
184 | XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label); | |
185 | return; | |
186 | ||
187 | case MATCH_DUP: | |
188 | printf (" x = "); | |
189 | print_path (path); | |
190 | printf (";\n"); | |
191 | ||
192 | printf (" if (!rtx_equal_p (operands[%d], x)) goto L%d;\n", | |
193 | XINT (x, 0), fail_label); | |
194 | return; | |
195 | ||
196 | case MATCH_OP_DUP: | |
197 | printf (" x = "); | |
198 | print_path (path); | |
199 | printf (";\n"); | |
200 | ||
201 | printf (" if (GET_CODE (operands[%d]) != GET_CODE (x)\n", XINT (x, 0)); | |
202 | printf (" || GET_MODE (operands[%d]) != GET_MODE (x)) goto L%d;\n", | |
203 | XINT (x, 0), fail_label); | |
204 | printf (" operands[%d] = x;\n", XINT (x, 0)); | |
205 | link.next = path; | |
206 | link.vecelt = -1; | |
207 | for (i = 0; i < XVECLEN (x, 1); i++) | |
208 | { | |
209 | link.pos = i; | |
210 | match_rtx (XVECEXP (x, 1, i), &link, fail_label); | |
211 | } | |
212 | return; | |
213 | ||
214 | case MATCH_OPERATOR: | |
215 | if (XINT (x, 0) > max_opno) | |
216 | max_opno = XINT (x, 0); | |
217 | if (XINT (x, 0) >= n_operands) | |
218 | n_operands = 1 + XINT (x, 0); | |
219 | ||
220 | printf (" x = "); | |
221 | print_path (path); | |
222 | printf (";\n"); | |
223 | ||
224 | printf (" operands[%d] = x;\n", XINT (x, 0)); | |
225 | if (XSTR (x, 1) && XSTR (x, 1)[0]) | |
226 | printf (" if (! %s (x, %smode)) goto L%d;\n", | |
227 | XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label); | |
228 | link.next = path; | |
229 | link.vecelt = -1; | |
230 | for (i = 0; i < XVECLEN (x, 2); i++) | |
231 | { | |
232 | link.pos = i; | |
233 | match_rtx (XVECEXP (x, 2, i), &link, fail_label); | |
234 | } | |
235 | return; | |
236 | ||
237 | case MATCH_PARALLEL: | |
238 | if (XINT (x, 0) > max_opno) | |
239 | max_opno = XINT (x, 0); | |
240 | if (XINT (x, 0) >= n_operands) | |
241 | n_operands = 1 + XINT (x, 0); | |
242 | ||
243 | printf (" x = "); | |
244 | print_path (path); | |
245 | printf (";\n"); | |
246 | ||
247 | printf (" if (GET_CODE (x) != PARALLEL) goto L%d;\n", fail_label); | |
248 | printf (" operands[%d] = x;\n", XINT (x, 0)); | |
249 | if (XSTR (x, 1) && XSTR (x, 1)[0]) | |
250 | printf (" if (! %s (x, %smode)) goto L%d;\n", | |
251 | XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label); | |
252 | link.next = path; | |
253 | link.pos = 0; | |
254 | for (i = 0; i < XVECLEN (x, 2); i++) | |
255 | { | |
256 | link.vecelt = i; | |
257 | match_rtx (XVECEXP (x, 2, i), &link, fail_label); | |
258 | } | |
259 | return; | |
260 | ||
261 | case ADDRESS: | |
262 | match_rtx (XEXP (x, 0), path, fail_label); | |
263 | return; | |
264 | } | |
265 | ||
266 | printf (" x = "); | |
267 | print_path (path); | |
268 | printf (";\n"); | |
269 | ||
270 | printf (" if (GET_CODE (x) != "); | |
271 | print_code (code); | |
272 | printf (") goto L%d;\n", fail_label); | |
273 | ||
274 | if (GET_MODE (x) != VOIDmode) | |
275 | { | |
276 | printf (" if (GET_MODE (x) != %smode) goto L%d;\n", | |
277 | GET_MODE_NAME (GET_MODE (x)), fail_label); | |
278 | } | |
279 | ||
280 | link.next = path; | |
281 | link.vecelt = -1; | |
282 | fmt = GET_RTX_FORMAT (code); | |
283 | len = GET_RTX_LENGTH (code); | |
284 | for (i = 0; i < len; i++) | |
285 | { | |
286 | link.pos = i; | |
287 | if (fmt[i] == 'e' || fmt[i] == 'u') | |
288 | match_rtx (XEXP (x, i), &link, fail_label); | |
289 | else if (fmt[i] == 'E') | |
290 | { | |
291 | int j; | |
292 | printf (" if (XVECLEN (x, %d) != %d) goto L%d;\n", | |
293 | i, XVECLEN (x, i), fail_label); | |
4231508a | 294 | for (j = 0; j < XVECLEN (x, i); j++) |
32f30c53 TW |
295 | { |
296 | link.vecelt = j; | |
297 | match_rtx (XVECEXP (x, i, j), &link, fail_label); | |
298 | } | |
299 | } | |
300 | else if (fmt[i] == 'i') | |
301 | { | |
302 | /* Make sure that at run time `x' is the RTX we want to test. */ | |
303 | if (i != 0) | |
304 | { | |
305 | printf (" x = "); | |
306 | print_path (path); | |
307 | printf (";\n"); | |
308 | } | |
309 | ||
310 | printf (" if (XINT (x, %d) != %d) goto L%d;\n", | |
311 | i, XINT (x, i), fail_label); | |
312 | } | |
313 | else if (fmt[i] == 's') | |
314 | { | |
315 | /* Make sure that at run time `x' is the RTX we want to test. */ | |
316 | if (i != 0) | |
317 | { | |
318 | printf (" x = "); | |
319 | print_path (path); | |
320 | printf (";\n"); | |
321 | } | |
322 | ||
323 | printf (" if (strcmp (XSTR (x, %d), \"%s\")) goto L%d;\n", | |
324 | i, XSTR (x, i), fail_label); | |
325 | } | |
326 | } | |
327 | } | |
328 | ||
329 | /* Given a PATH, representing a path down the instruction's | |
330 | pattern from the root to a certain point, output code to | |
331 | evaluate to the rtx at that point. */ | |
332 | ||
333 | static void | |
334 | print_path (path) | |
335 | struct link *path; | |
336 | { | |
337 | if (path == 0) | |
338 | printf ("pat"); | |
339 | else if (path->vecelt >= 0) | |
340 | { | |
341 | printf ("XVECEXP ("); | |
342 | print_path (path->next); | |
343 | printf (", %d, %d)", path->pos, path->vecelt); | |
344 | } | |
345 | else | |
346 | { | |
347 | printf ("XEXP ("); | |
348 | print_path (path->next); | |
349 | printf (", %d)", path->pos); | |
350 | } | |
351 | } | |
352 | \f | |
353 | static void | |
354 | print_code (code) | |
355 | RTX_CODE code; | |
356 | { | |
357 | register char *p1; | |
358 | for (p1 = GET_RTX_NAME (code); *p1; p1++) | |
359 | { | |
360 | if (*p1 >= 'a' && *p1 <= 'z') | |
361 | putchar (*p1 + 'A' - 'a'); | |
362 | else | |
363 | putchar (*p1); | |
364 | } | |
365 | } | |
366 | \f | |
367 | char * | |
368 | xmalloc (size) | |
369 | unsigned size; | |
370 | { | |
371 | register char *val = (char *) malloc (size); | |
372 | ||
373 | if (val == 0) | |
374 | fatal ("virtual memory exhausted"); | |
375 | return val; | |
376 | } | |
377 | ||
378 | char * | |
379 | xrealloc (ptr, size) | |
380 | char *ptr; | |
381 | unsigned size; | |
382 | { | |
383 | char *result = (char *) realloc (ptr, size); | |
384 | if (!result) | |
385 | fatal ("virtual memory exhausted"); | |
386 | return result; | |
387 | } | |
388 | ||
389 | static void | |
390 | fatal (s, a1, a2) | |
391 | char *s; | |
392 | { | |
393 | fprintf (stderr, "genpeep: "); | |
394 | fprintf (stderr, s, a1, a2); | |
395 | fprintf (stderr, "\n"); | |
396 | exit (FATAL_EXIT_CODE); | |
397 | } | |
398 | ||
399 | /* More 'friendly' abort that prints the line and file. | |
400 | config.h can #define abort fancy_abort if you like that sort of thing. */ | |
401 | ||
402 | void | |
403 | fancy_abort () | |
404 | { | |
405 | fatal ("Internal gcc abort."); | |
406 | } | |
407 | \f | |
408 | int | |
409 | main (argc, argv) | |
410 | int argc; | |
411 | char **argv; | |
412 | { | |
413 | rtx desc; | |
414 | FILE *infile; | |
415 | extern rtx read_rtx (); | |
416 | register int c; | |
417 | ||
418 | max_opno = -1; | |
419 | ||
420 | obstack_init (rtl_obstack); | |
421 | ||
422 | if (argc <= 1) | |
423 | fatal ("No input file name."); | |
424 | ||
425 | infile = fopen (argv[1], "r"); | |
426 | if (infile == 0) | |
427 | { | |
428 | perror (argv[1]); | |
429 | exit (FATAL_EXIT_CODE); | |
430 | } | |
431 | ||
432 | init_rtl (); | |
433 | ||
434 | printf ("/* Generated automatically by the program `genpeep'\n\ | |
435 | from the machine description file `md'. */\n\n"); | |
436 | ||
437 | printf ("#include \"config.h\"\n"); | |
438 | printf ("#include \"rtl.h\"\n"); | |
439 | printf ("#include \"regs.h\"\n"); | |
440 | printf ("#include \"output.h\"\n"); | |
441 | printf ("#include \"real.h\"\n\n"); | |
442 | ||
443 | printf ("extern rtx peep_operand[];\n\n"); | |
444 | printf ("#define operands peep_operand\n\n"); | |
445 | ||
446 | printf ("rtx\npeephole (ins1)\n rtx ins1;\n{\n"); | |
447 | printf (" rtx insn, x, pat;\n"); | |
448 | printf (" int i;\n\n"); | |
449 | ||
450 | /* Early out: no peepholes for insns followed by barriers. */ | |
451 | printf (" if (NEXT_INSN (ins1)\n"); | |
452 | printf (" && GET_CODE (NEXT_INSN (ins1)) == BARRIER)\n"); | |
453 | printf (" return 0;\n\n"); | |
454 | ||
455 | /* Read the machine description. */ | |
456 | ||
457 | while (1) | |
458 | { | |
459 | c = read_skip_spaces (infile); | |
460 | if (c == EOF) | |
461 | break; | |
462 | ungetc (c, infile); | |
463 | ||
464 | desc = read_rtx (infile); | |
465 | if (GET_CODE (desc) == DEFINE_PEEPHOLE) | |
466 | { | |
467 | gen_peephole (desc); | |
468 | insn_code_number++; | |
469 | } | |
470 | if (GET_CODE (desc) == DEFINE_INSN | |
471 | || GET_CODE (desc) == DEFINE_EXPAND | |
472 | || GET_CODE (desc) == DEFINE_SPLIT) | |
473 | { | |
474 | insn_code_number++; | |
475 | } | |
476 | } | |
477 | ||
478 | printf (" return 0;\n}\n\n"); | |
479 | ||
480 | if (max_opno == -1) | |
481 | max_opno = 1; | |
482 | ||
483 | printf ("rtx peep_operand[%d];\n", max_opno + 1); | |
484 | ||
485 | fflush (stdout); | |
486 | exit (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE); | |
487 | /* NOTREACHED */ | |
488 | return 0; | |
489 | } |