1 /* Generate code from machine description to perform peephole optimizations.
2 Copyright (C) 1987, 1989, 1992, 1997, 1998,
3 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
29 static struct obstack obstack;
30 struct obstack *rtl_obstack = &obstack;
32 #define obstack_chunk_alloc xmalloc
33 #define obstack_chunk_free free
35 /* While tree-walking an instruction pattern, we keep a chain
36 of these `struct link's to record how to get down to the
37 current position. In each one, POS is the operand number,
38 and if the operand is a vector VEC is the element number.
39 VEC is -1 if the operand is not a vector. */
50 /* Number of operands used in current peephole definition. */
52 static int n_operands;
54 /* Peephole optimizations get insn codes just like insn patterns.
55 Count them so we know the code of the define_peephole we are handling. */
57 static int insn_code_number = 0;
59 static void gen_peephole PARAMS ((rtx));
60 static void match_rtx PARAMS ((rtx, struct link *, int));
61 static void print_path PARAMS ((struct link *));
62 static void print_code PARAMS ((RTX_CODE));
68 int ninsns = XVECLEN (peep, 0);
73 printf (" insn = ins1;\n");
75 printf (" want_jump = 0;\n");
78 for (i = 0; i < ninsns; i++)
82 printf (" do { insn = NEXT_INSN (insn);\n");
83 printf (" if (insn == 0) goto L%d; }\n",
85 printf (" while (GET_CODE (insn) == NOTE\n");
86 printf ("\t || (GET_CODE (insn) == INSN\n");
87 printf ("\t && (GET_CODE (PATTERN (insn)) == USE\n");
88 printf ("\t\t || GET_CODE (PATTERN (insn)) == CLOBBER)));\n");
90 printf (" if (GET_CODE (insn) == CODE_LABEL\n\
91 || GET_CODE (insn) == BARRIER)\n goto L%d;\n",
96 printf (" if (GET_CODE (insn) == JUMP_INSN)\n");
97 printf (" want_jump = JUMP_LABEL (insn);\n");
100 printf (" pat = PATTERN (insn);\n");
102 /* Walk the insn's pattern, remembering at all times the path
103 down to the walking point. */
105 match_rtx (XVECEXP (peep, 0, i), NULL_PTR, insn_code_number);
108 /* We get this far if the pattern matches.
109 Now test the extra condition. */
111 if (XSTR (peep, 1) && XSTR (peep, 1)[0])
112 printf (" if (! (%s)) goto L%d;\n",
113 XSTR (peep, 1), insn_code_number);
115 /* If that matches, construct new pattern and put it in the first insn.
116 This new pattern will never be matched.
117 It exists only so that insn-extract can get the operands back.
118 So use a simple regular form: a PARALLEL containing a vector
119 of all the operands. */
121 printf (" PATTERN (ins1) = gen_rtx_PARALLEL (VOIDmode, gen_rtvec_v (%d, operands));\n", n_operands);
124 printf (" if (want_jump && GET_CODE (ins1) != JUMP_INSN)\n");
126 printf (" rtx insn2 = emit_jump_insn_before (PATTERN (ins1), ins1);\n");
127 printf (" delete_insn (ins1);\n");
128 printf (" ins1 = ins2;\n");
132 /* Record this define_peephole's insn code in the insn,
133 as if it had been recognized to match this. */
134 printf (" INSN_CODE (ins1) = %d;\n",
137 /* Delete the remaining insns. */
139 printf (" delete_for_peephole (NEXT_INSN (ins1), insn);\n");
141 /* See reload1.c for insertion of NOTE which guarantees that this
143 printf (" return NEXT_INSN (insn);\n");
145 printf (" L%d:\n\n", insn_code_number);
149 match_rtx (x, path, fail_label)
154 register RTX_CODE code;
157 register const char *fmt;
169 if (XINT (x, 0) > max_opno)
170 max_opno = XINT (x, 0);
171 if (XINT (x, 0) >= n_operands)
172 n_operands = 1 + XINT (x, 0);
178 printf (" operands[%d] = x;\n", XINT (x, 0));
179 if (XSTR (x, 1) && XSTR (x, 1)[0])
180 printf (" if (! %s (x, %smode)) goto L%d;\n",
181 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
190 printf (" if (!rtx_equal_p (operands[%d], x)) goto L%d;\n",
191 XINT (x, 0), fail_label);
199 printf (" if (GET_CODE (operands[%d]) != GET_CODE (x)\n", XINT (x, 0));
200 printf (" || GET_MODE (operands[%d]) != GET_MODE (x)) goto L%d;\n",
201 XINT (x, 0), fail_label);
202 printf (" operands[%d] = x;\n", XINT (x, 0));
205 for (i = 0; i < XVECLEN (x, 1); i++)
208 match_rtx (XVECEXP (x, 1, i), &link, fail_label);
213 if (XINT (x, 0) > max_opno)
214 max_opno = XINT (x, 0);
215 if (XINT (x, 0) >= n_operands)
216 n_operands = 1 + XINT (x, 0);
222 printf (" operands[%d] = x;\n", XINT (x, 0));
223 if (XSTR (x, 1) && XSTR (x, 1)[0])
224 printf (" if (! %s (x, %smode)) goto L%d;\n",
225 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
228 for (i = 0; i < XVECLEN (x, 2); i++)
231 match_rtx (XVECEXP (x, 2, i), &link, fail_label);
236 if (XINT (x, 0) > max_opno)
237 max_opno = XINT (x, 0);
238 if (XINT (x, 0) >= n_operands)
239 n_operands = 1 + XINT (x, 0);
245 printf (" if (GET_CODE (x) != PARALLEL) goto L%d;\n", fail_label);
246 printf (" operands[%d] = x;\n", XINT (x, 0));
247 if (XSTR (x, 1) && XSTR (x, 1)[0])
248 printf (" if (! %s (x, %smode)) goto L%d;\n",
249 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
252 for (i = 0; i < XVECLEN (x, 2); i++)
255 match_rtx (XVECEXP (x, 2, i), &link, fail_label);
260 match_rtx (XEXP (x, 0), path, fail_label);
271 printf (" if (GET_CODE (x) != ");
273 printf (") goto L%d;\n", fail_label);
275 if (GET_MODE (x) != VOIDmode)
277 printf (" if (GET_MODE (x) != %smode) goto L%d;\n",
278 GET_MODE_NAME (GET_MODE (x)), fail_label);
283 fmt = GET_RTX_FORMAT (code);
284 len = GET_RTX_LENGTH (code);
285 for (i = 0; i < len; i++)
288 if (fmt[i] == 'e' || fmt[i] == 'u')
289 match_rtx (XEXP (x, i), &link, fail_label);
290 else if (fmt[i] == 'E')
293 printf (" if (XVECLEN (x, %d) != %d) goto L%d;\n",
294 i, XVECLEN (x, i), fail_label);
295 for (j = 0; j < XVECLEN (x, i); j++)
298 match_rtx (XVECEXP (x, i, j), &link, fail_label);
301 else if (fmt[i] == 'i')
303 /* Make sure that at run time `x' is the RTX we want to test. */
311 printf (" if (XINT (x, %d) != %d) goto L%d;\n",
312 i, XINT (x, i), fail_label);
314 else if (fmt[i] == 'w')
316 /* Make sure that at run time `x' is the RTX we want to test. */
324 printf (" if (XWINT (x, %d) != ", i);
325 printf (HOST_WIDE_INT_PRINT_DEC, XWINT (x, i));
326 printf (") goto L%d;\n", fail_label);
328 else if (fmt[i] == 's')
330 /* Make sure that at run time `x' is the RTX we want to test. */
338 printf (" if (strcmp (XSTR (x, %d), \"%s\")) goto L%d;\n",
339 i, XSTR (x, i), fail_label);
344 /* Given a PATH, representing a path down the instruction's
345 pattern from the root to a certain point, output code to
346 evaluate to the rtx at that point. */
354 else if (path->vecelt >= 0)
356 printf ("XVECEXP (");
357 print_path (path->next);
358 printf (", %d, %d)", path->pos, path->vecelt);
363 print_path (path->next);
364 printf (", %d)", path->pos);
372 register const char *p1;
373 for (p1 = GET_RTX_NAME (code); *p1; p1++)
374 putchar (TOUPPER(*p1));
381 register PTR val = (PTR) malloc (size);
384 fatal ("virtual memory exhausted");
395 ptr = (PTR) realloc (old, size);
397 ptr = (PTR) malloc (size);
399 fatal ("virtual memory exhausted");
403 extern int main PARAMS ((int, char **));
416 progname = "genpeep";
417 obstack_init (rtl_obstack);
420 fatal ("No input file name.");
422 infile = fopen (argv[1], "r");
426 return (FATAL_EXIT_CODE);
428 read_rtx_filename = argv[1];
430 printf ("/* Generated automatically by the program `genpeep'\n\
431 from the machine description file `md'. */\n\n");
433 printf ("#include \"config.h\"\n");
434 printf ("#include \"system.h\"\n");
435 printf ("#include \"insn-config.h\"\n");
436 printf ("#include \"rtl.h\"\n");
437 printf ("#include \"tm_p.h\"\n");
438 printf ("#include \"regs.h\"\n");
439 printf ("#include \"output.h\"\n");
440 printf ("#include \"real.h\"\n");
441 printf ("#include \"recog.h\"\n");
442 printf ("#include \"except.h\"\n\n");
443 printf ("#include \"function.h\"\n\n");
445 printf ("#ifdef HAVE_peephole\n");
446 printf ("extern rtx peep_operand[];\n\n");
447 printf ("#define operands peep_operand\n\n");
449 printf ("rtx\npeephole (ins1)\n rtx ins1;\n{\n");
450 printf (" rtx insn ATTRIBUTE_UNUSED, x ATTRIBUTE_UNUSED, pat ATTRIBUTE_UNUSED;\n\n");
452 /* Early out: no peepholes for insns followed by barriers. */
453 printf (" if (NEXT_INSN (ins1)\n");
454 printf (" && GET_CODE (NEXT_INSN (ins1)) == BARRIER)\n");
455 printf (" return 0;\n\n");
457 /* Read the machine description. */
461 c = read_skip_spaces (infile);
466 desc = read_rtx (infile);
467 if (GET_CODE (desc) == DEFINE_PEEPHOLE)
472 if (GET_CODE (desc) == DEFINE_INSN
473 || GET_CODE (desc) == DEFINE_EXPAND
474 || GET_CODE (desc) == DEFINE_SPLIT)
480 printf (" return 0;\n}\n\n");
485 printf ("rtx peep_operand[%d];\n", max_opno + 1);
489 return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
492 /* Define this so we can link with print-rtl.o to get debug_rtx function. */
495 int code ATTRIBUTE_UNUSED;