1 /* Generate code from machine description to perform peephole optimizations.
2 Copyright (C) 1987, 1989, 1992, 1997, 1998 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
33 /* Define this so we can link with print-rtl.o to get debug_rtx function. */
34 char **insn_name_ptr = 0;
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. */
49 char *xmalloc PROTO((unsigned));
50 static void fatal PVPROTO ((char *, ...))
51 ATTRIBUTE_PRINTF_1 ATTRIBUTE_NORETURN;
52 void fancy_abort PROTO((void)) ATTRIBUTE_NORETURN;
56 /* Number of operands used in current peephole definition. */
58 static int n_operands;
60 /* Peephole optimizations get insn codes just like insn patterns.
61 Count them so we know the code of the define_peephole we are handling. */
63 static int insn_code_number = 0;
65 static void gen_peephole PROTO((rtx));
66 static void match_rtx PROTO((rtx, struct link *, int));
67 static void print_path PROTO((struct link *));
68 static void print_code PROTO((RTX_CODE));
74 int ninsns = XVECLEN (peep, 0);
79 printf (" insn = ins1;\n");
81 printf (" want_jump = 0;\n");
84 for (i = 0; i < ninsns; i++)
88 printf (" do { insn = NEXT_INSN (insn);\n");
89 printf (" if (insn == 0) goto L%d; }\n",
91 printf (" while (GET_CODE (insn) == NOTE\n");
92 printf ("\t || (GET_CODE (insn) == INSN\n");
93 printf ("\t && (GET_CODE (PATTERN (insn)) == USE\n");
94 printf ("\t\t || GET_CODE (PATTERN (insn)) == CLOBBER)));\n");
96 printf (" if (GET_CODE (insn) == CODE_LABEL\n\
97 || GET_CODE (insn) == BARRIER)\n goto L%d;\n",
102 printf (" if (GET_CODE (insn) == JUMP_INSN)\n");
103 printf (" want_jump = JUMP_LABEL (insn);\n");
106 printf (" pat = PATTERN (insn);\n");
108 /* Walk the insn's pattern, remembering at all times the path
109 down to the walking point. */
111 match_rtx (XVECEXP (peep, 0, i), NULL_PTR, insn_code_number);
114 /* We get this far if the pattern matches.
115 Now test the extra condition. */
117 if (XSTR (peep, 1) && XSTR (peep, 1)[0])
118 printf (" if (! (%s)) goto L%d;\n",
119 XSTR (peep, 1), insn_code_number);
121 /* If that matches, construct new pattern and put it in the first insn.
122 This new pattern will never be matched.
123 It exists only so that insn-extract can get the operands back.
124 So use a simple regular form: a PARALLEL containing a vector
125 of all the operands. */
127 printf (" PATTERN (ins1) = gen_rtx_PARALLEL (VOIDmode, gen_rtvec_v (%d, operands));\n", n_operands);
130 printf (" if (want_jump && GET_CODE (ins1) != JUMP_INSN)\n");
132 printf (" rtx insn2 = emit_jump_insn_before (PATTERN (ins1), ins1);\n");
133 printf (" delete_insn (ins1);\n");
134 printf (" ins1 = ins2;\n");
138 /* Record this define_peephole's insn code in the insn,
139 as if it had been recognized to match this. */
140 printf (" INSN_CODE (ins1) = %d;\n",
143 /* Delete the remaining insns. */
145 printf (" delete_for_peephole (NEXT_INSN (ins1), insn);\n");
147 /* See reload1.c for insertion of NOTE which guarantees that this
149 printf (" return NEXT_INSN (insn);\n");
151 printf (" L%d:\n\n", insn_code_number);
155 match_rtx (x, path, fail_label)
160 register RTX_CODE code;
175 if (XINT (x, 0) > max_opno)
176 max_opno = XINT (x, 0);
177 if (XINT (x, 0) >= n_operands)
178 n_operands = 1 + XINT (x, 0);
184 printf (" operands[%d] = x;\n", XINT (x, 0));
185 if (XSTR (x, 1) && XSTR (x, 1)[0])
186 printf (" if (! %s (x, %smode)) goto L%d;\n",
187 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
196 printf (" if (!rtx_equal_p (operands[%d], x)) goto L%d;\n",
197 XINT (x, 0), fail_label);
205 printf (" if (GET_CODE (operands[%d]) != GET_CODE (x)\n", XINT (x, 0));
206 printf (" || GET_MODE (operands[%d]) != GET_MODE (x)) goto L%d;\n",
207 XINT (x, 0), fail_label);
208 printf (" operands[%d] = x;\n", XINT (x, 0));
211 for (i = 0; i < XVECLEN (x, 1); i++)
214 match_rtx (XVECEXP (x, 1, i), &link, fail_label);
219 if (XINT (x, 0) > max_opno)
220 max_opno = XINT (x, 0);
221 if (XINT (x, 0) >= n_operands)
222 n_operands = 1 + XINT (x, 0);
228 printf (" operands[%d] = x;\n", XINT (x, 0));
229 if (XSTR (x, 1) && XSTR (x, 1)[0])
230 printf (" if (! %s (x, %smode)) goto L%d;\n",
231 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
234 for (i = 0; i < XVECLEN (x, 2); i++)
237 match_rtx (XVECEXP (x, 2, i), &link, fail_label);
242 if (XINT (x, 0) > max_opno)
243 max_opno = XINT (x, 0);
244 if (XINT (x, 0) >= n_operands)
245 n_operands = 1 + XINT (x, 0);
251 printf (" if (GET_CODE (x) != PARALLEL) goto L%d;\n", fail_label);
252 printf (" operands[%d] = x;\n", XINT (x, 0));
253 if (XSTR (x, 1) && XSTR (x, 1)[0])
254 printf (" if (! %s (x, %smode)) goto L%d;\n",
255 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
258 for (i = 0; i < XVECLEN (x, 2); i++)
261 match_rtx (XVECEXP (x, 2, i), &link, fail_label);
266 match_rtx (XEXP (x, 0), path, fail_label);
277 printf (" if (GET_CODE (x) != ");
279 printf (") goto L%d;\n", fail_label);
281 if (GET_MODE (x) != VOIDmode)
283 printf (" if (GET_MODE (x) != %smode) goto L%d;\n",
284 GET_MODE_NAME (GET_MODE (x)), fail_label);
289 fmt = GET_RTX_FORMAT (code);
290 len = GET_RTX_LENGTH (code);
291 for (i = 0; i < len; i++)
294 if (fmt[i] == 'e' || fmt[i] == 'u')
295 match_rtx (XEXP (x, i), &link, fail_label);
296 else if (fmt[i] == 'E')
299 printf (" if (XVECLEN (x, %d) != %d) goto L%d;\n",
300 i, XVECLEN (x, i), fail_label);
301 for (j = 0; j < XVECLEN (x, i); j++)
304 match_rtx (XVECEXP (x, i, j), &link, fail_label);
307 else if (fmt[i] == 'i')
309 /* Make sure that at run time `x' is the RTX we want to test. */
317 printf (" if (XINT (x, %d) != %d) goto L%d;\n",
318 i, XINT (x, i), fail_label);
320 else if (fmt[i] == 'w')
322 /* Make sure that at run time `x' is the RTX we want to test. */
330 printf (" if (XWINT (x, %d) != ", i);
331 printf (HOST_WIDE_INT_PRINT_DEC, XWINT (x, i));
332 printf (") goto L%d;\n", 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");
411 fatal VPROTO ((char *format, ...))
418 VA_START (ap, format);
421 format = va_arg (ap, char *);
424 fprintf (stderr, "genpeep: ");
425 vfprintf (stderr, format, ap);
427 fprintf (stderr, "\n");
428 exit (FATAL_EXIT_CODE);
431 /* More 'friendly' abort that prints the line and file.
432 config.h can #define abort fancy_abort if you like that sort of thing. */
437 fatal ("Internal gcc abort.");
451 obstack_init (rtl_obstack);
454 fatal ("No input file name.");
456 infile = fopen (argv[1], "r");
460 exit (FATAL_EXIT_CODE);
465 printf ("/* Generated automatically by the program `genpeep'\n\
466 from the machine description file `md'. */\n\n");
468 printf ("#include \"config.h\"\n");
469 printf ("#include \"system.h\"\n");
470 printf ("#include \"insn-config.h\"\n");
471 printf ("#include \"rtl.h\"\n");
472 printf ("#include \"regs.h\"\n");
473 printf ("#include \"output.h\"\n");
474 printf ("#include \"real.h\"\n");
475 printf ("#include \"recog.h\"\n");
476 printf ("#include \"except.h\"\n\n");
478 printf ("extern rtx peep_operand[];\n\n");
479 printf ("#define operands peep_operand\n\n");
481 printf ("rtx\npeephole (ins1)\n rtx ins1;\n{\n");
482 printf (" rtx insn ATTRIBUTE_UNUSED, x ATTRIBUTE_UNUSED, pat ATTRIBUTE_UNUSED;\n\n");
484 /* Early out: no peepholes for insns followed by barriers. */
485 printf (" if (NEXT_INSN (ins1)\n");
486 printf (" && GET_CODE (NEXT_INSN (ins1)) == BARRIER)\n");
487 printf (" return 0;\n\n");
489 /* Read the machine description. */
493 c = read_skip_spaces (infile);
498 desc = read_rtx (infile);
499 if (GET_CODE (desc) == DEFINE_PEEPHOLE)
504 if (GET_CODE (desc) == DEFINE_INSN
505 || GET_CODE (desc) == DEFINE_EXPAND
506 || GET_CODE (desc) == DEFINE_SPLIT)
512 printf (" return 0;\n}\n\n");
517 printf ("rtx peep_operand[%d];\n", max_opno + 1);
520 exit (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);