1 /* Generate code from machine description to perform peephole optimizations.
2 Copyright (C) 1987, 1989, 1992 Free Software Foundation, Inc.
4 This file is part of GNU CC.
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)
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.
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, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
27 static struct obstack obstack;
28 struct obstack *rtl_obstack = &obstack;
30 #define obstack_chunk_alloc xmalloc
31 #define obstack_chunk_free free
34 extern rtx read_rtx ();
36 /* While tree-walking an instruction pattern, we keep a chain
37 of these `struct link's to record how to get down to the
38 current position. In each one, POS is the operand number,
39 and if the operand is a vector VEC is the element number.
40 VEC is -1 if the operand is not a vector. */
50 static void match_rtx ();
51 static void gen_exp ();
57 /* Number of operands used in current peephole definition. */
59 static int n_operands;
61 /* Peephole optimizations get insn codes just like insn patterns.
62 Count them so we know the code of the define_peephole we are handling. */
64 static int insn_code_number = 0;
66 static void print_path ();
67 static void print_code ();
73 int ninsns = XVECLEN (peep, 0);
78 printf (" insn = ins1;\n");
80 printf (" want_jump = 0;\n");
83 for (i = 0; i < ninsns; i++)
87 printf (" do { insn = NEXT_INSN (insn);\n");
88 printf (" if (insn == 0) goto L%d; }\n",
90 printf (" while (GET_CODE (insn) == NOTE\n");
91 printf ("\t || (GET_CODE (insn) == INSN\n");
92 printf ("\t && (GET_CODE (PATTERN (insn)) == USE\n");
93 printf ("\t\t || GET_CODE (PATTERN (insn)) == CLOBBER)));\n");
95 printf (" if (GET_CODE (insn) == CODE_LABEL\n\
96 || GET_CODE (insn) == BARRIER)\n goto L%d;\n",
101 printf (" if (GET_CODE (insn) == JUMP_INSN)\n");
102 printf (" want_jump = JUMP_LABEL (insn);\n");
105 printf (" pat = PATTERN (insn);\n");
107 /* Walk the insn's pattern, remembering at all times the path
108 down to the walking point. */
110 match_rtx (XVECEXP (peep, 0, i), NULL_PTR, insn_code_number);
113 /* We get this far if the pattern matches.
114 Now test the extra condition. */
116 if (XSTR (peep, 1) && XSTR (peep, 1)[0])
117 printf (" if (! (%s)) goto L%d;\n",
118 XSTR (peep, 1), insn_code_number);
120 /* If that matches, construct new pattern and put it in the first insn.
121 This new pattern will never be matched.
122 It exists only so that insn-extract can get the operands back.
123 So use a simple regular form: a PARALLEL containing a vector
124 of all the operands. */
126 printf (" PATTERN (ins1) = gen_rtx (PARALLEL, VOIDmode, gen_rtvec_v (%d, operands));\n", n_operands);
129 printf (" if (want_jump && GET_CODE (ins1) != JUMP_INSN)\n");
131 printf (" rtx insn2 = emit_jump_insn_before (PATTERN (ins1), ins1);\n");
132 printf (" delete_insn (ins1);\n");
133 printf (" ins1 = ins2;\n");
137 /* Record this define_peephole's insn code in the insn,
138 as if it had been recognized to match this. */
139 printf (" INSN_CODE (ins1) = %d;\n",
142 /* Delete the remaining insns. */
144 printf (" delete_for_peephole (NEXT_INSN (ins1), insn);\n");
146 /* See reload1.c for insertion of NOTE which guarantees that this
148 printf (" return NEXT_INSN (insn);\n");
150 printf (" L%d:\n\n", insn_code_number);
154 match_rtx (x, path, fail_label)
159 register RTX_CODE code;
174 if (XINT (x, 0) > max_opno)
175 max_opno = XINT (x, 0);
176 if (XINT (x, 0) >= n_operands)
177 n_operands = 1 + XINT (x, 0);
183 printf (" operands[%d] = x;\n", XINT (x, 0));
184 if (XSTR (x, 1) && XSTR (x, 1)[0])
185 printf (" if (! %s (x, %smode)) goto L%d;\n",
186 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
195 printf (" if (!rtx_equal_p (operands[%d], x)) goto L%d;\n",
196 XINT (x, 0), fail_label);
204 printf (" if (GET_CODE (operands[%d]) != GET_CODE (x)\n", XINT (x, 0));
205 printf (" || GET_MODE (operands[%d]) != GET_MODE (x)) goto L%d;\n",
206 XINT (x, 0), fail_label);
207 printf (" operands[%d] = x;\n", XINT (x, 0));
210 for (i = 0; i < XVECLEN (x, 1); i++)
213 match_rtx (XVECEXP (x, 1, i), &link, fail_label);
218 if (XINT (x, 0) > max_opno)
219 max_opno = XINT (x, 0);
220 if (XINT (x, 0) >= n_operands)
221 n_operands = 1 + XINT (x, 0);
227 printf (" operands[%d] = x;\n", XINT (x, 0));
228 if (XSTR (x, 1) && XSTR (x, 1)[0])
229 printf (" if (! %s (x, %smode)) goto L%d;\n",
230 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
233 for (i = 0; i < XVECLEN (x, 2); i++)
236 match_rtx (XVECEXP (x, 2, i), &link, fail_label);
241 if (XINT (x, 0) > max_opno)
242 max_opno = XINT (x, 0);
243 if (XINT (x, 0) >= n_operands)
244 n_operands = 1 + XINT (x, 0);
250 printf (" if (GET_CODE (x) != PARALLEL) goto L%d;\n", fail_label);
251 printf (" operands[%d] = x;\n", XINT (x, 0));
252 if (XSTR (x, 1) && XSTR (x, 1)[0])
253 printf (" if (! %s (x, %smode)) goto L%d;\n",
254 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
257 for (i = 0; i < XVECLEN (x, 2); i++)
260 match_rtx (XVECEXP (x, 2, i), &link, fail_label);
265 match_rtx (XEXP (x, 0), path, fail_label);
273 printf (" if (GET_CODE (x) != ");
275 printf (") goto L%d;\n", fail_label);
277 if (GET_MODE (x) != VOIDmode)
279 printf (" if (GET_MODE (x) != %smode) goto L%d;\n",
280 GET_MODE_NAME (GET_MODE (x)), fail_label);
285 fmt = GET_RTX_FORMAT (code);
286 len = GET_RTX_LENGTH (code);
287 for (i = 0; i < len; i++)
290 if (fmt[i] == 'e' || fmt[i] == 'u')
291 match_rtx (XEXP (x, i), &link, fail_label);
292 else if (fmt[i] == 'E')
295 printf (" if (XVECLEN (x, %d) != %d) goto L%d;\n",
296 i, XVECLEN (x, i), fail_label);
297 for (j = 0; j < XVECLEN (x, i); j++)
300 match_rtx (XVECEXP (x, i, j), &link, fail_label);
303 else if (fmt[i] == 'i')
305 /* Make sure that at run time `x' is the RTX we want to test. */
313 printf (" if (XINT (x, %d) != %d) goto L%d;\n",
314 i, XINT (x, i), fail_label);
316 else if (fmt[i] == 'w')
318 /* Make sure that at run time `x' is the RTX we want to test. */
326 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
327 printf (" if (XWINT (x, %d) != %d) goto L%d;\n",
328 i, XWINT (x, i), fail_label);
330 printf (" if (XWINT (x, %d) != %ld) goto L%d;\n",
331 i, XWINT (x, i), fail_label);
334 else if (fmt[i] == 's')
336 /* Make sure that at run time `x' is the RTX we want to test. */
344 printf (" if (strcmp (XSTR (x, %d), \"%s\")) goto L%d;\n",
345 i, XSTR (x, i), fail_label);
350 /* Given a PATH, representing a path down the instruction's
351 pattern from the root to a certain point, output code to
352 evaluate to the rtx at that point. */
360 else if (path->vecelt >= 0)
362 printf ("XVECEXP (");
363 print_path (path->next);
364 printf (", %d, %d)", path->pos, path->vecelt);
369 print_path (path->next);
370 printf (", %d)", path->pos);
379 for (p1 = GET_RTX_NAME (code); *p1; p1++)
381 if (*p1 >= 'a' && *p1 <= 'z')
382 putchar (*p1 + 'A' - 'a');
392 register char *val = (char *) malloc (size);
395 fatal ("virtual memory exhausted");
404 char *result = (char *) realloc (ptr, size);
406 fatal ("virtual memory exhausted");
414 fprintf (stderr, "genpeep: ");
415 fprintf (stderr, s, a1, a2);
416 fprintf (stderr, "\n");
417 exit (FATAL_EXIT_CODE);
420 /* More 'friendly' abort that prints the line and file.
421 config.h can #define abort fancy_abort if you like that sort of thing. */
426 fatal ("Internal gcc abort.");
440 obstack_init (rtl_obstack);
443 fatal ("No input file name.");
445 infile = fopen (argv[1], "r");
449 exit (FATAL_EXIT_CODE);
454 printf ("/* Generated automatically by the program `genpeep'\n\
455 from the machine description file `md'. */\n\n");
457 printf ("#include \"config.h\"\n");
458 printf ("#include \"rtl.h\"\n");
459 printf ("#include \"regs.h\"\n");
460 printf ("#include \"output.h\"\n");
461 printf ("#include \"real.h\"\n\n");
463 printf ("extern rtx peep_operand[];\n\n");
464 printf ("#define operands peep_operand\n\n");
466 printf ("rtx\npeephole (ins1)\n rtx ins1;\n{\n");
467 printf (" rtx insn, x, pat;\n");
468 printf (" int i;\n\n");
470 /* Early out: no peepholes for insns followed by barriers. */
471 printf (" if (NEXT_INSN (ins1)\n");
472 printf (" && GET_CODE (NEXT_INSN (ins1)) == BARRIER)\n");
473 printf (" return 0;\n\n");
475 /* Read the machine description. */
479 c = read_skip_spaces (infile);
484 desc = read_rtx (infile);
485 if (GET_CODE (desc) == DEFINE_PEEPHOLE)
490 if (GET_CODE (desc) == DEFINE_INSN
491 || GET_CODE (desc) == DEFINE_EXPAND
492 || GET_CODE (desc) == DEFINE_SPLIT)
498 printf (" return 0;\n}\n\n");
503 printf ("rtx peep_operand[%d];\n", max_opno + 1);
506 exit (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);