1 /* Generate code from machine description to perform peephole optimizations.
2 Copyright (C) 1987, 1989, 1992, 1997, 1998, 1999, 2000, 2003, 2004,
3 2007 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
24 #include "coretypes.h"
28 #include "gensupport.h"
31 /* While tree-walking an instruction pattern, we keep a chain
32 of these `struct link's to record how to get down to the
33 current position. In each one, POS is the operand number,
34 and if the operand is a vector VEC is the element number.
35 VEC is -1 if the operand is not a vector. */
46 /* Number of operands used in current peephole definition. */
48 static int n_operands;
50 /* Peephole optimizations get insn codes just like insn patterns.
51 Count them so we know the code of the define_peephole we are handling. */
53 static int insn_code_number = 0;
55 static void gen_peephole (rtx);
56 static void match_rtx (rtx, struct link *, int);
57 static void print_path (struct link *);
58 static void print_code (RTX_CODE);
61 gen_peephole (rtx peep)
63 int ninsns = XVECLEN (peep, 0);
68 printf (" insn = ins1;\n");
70 for (i = 0; i < ninsns; i++)
74 printf (" do { insn = NEXT_INSN (insn);\n");
75 printf (" if (insn == 0) goto L%d; }\n",
77 printf (" while (NOTE_P (insn)\n");
78 printf ("\t || (NONJUMP_INSN_P (insn)\n");
79 printf ("\t && (GET_CODE (PATTERN (insn)) == USE\n");
80 printf ("\t\t || GET_CODE (PATTERN (insn)) == CLOBBER)));\n");
82 printf (" if (LABEL_P (insn)\n\
83 || BARRIER_P (insn))\n goto L%d;\n",
87 printf (" pat = PATTERN (insn);\n");
89 /* Walk the insn's pattern, remembering at all times the path
90 down to the walking point. */
92 match_rtx (XVECEXP (peep, 0, i), NULL, insn_code_number);
95 /* We get this far if the pattern matches.
96 Now test the extra condition. */
98 if (XSTR (peep, 1) && XSTR (peep, 1)[0])
99 printf (" if (! (%s)) goto L%d;\n",
100 XSTR (peep, 1), insn_code_number);
102 /* If that matches, construct new pattern and put it in the first insn.
103 This new pattern will never be matched.
104 It exists only so that insn-extract can get the operands back.
105 So use a simple regular form: a PARALLEL containing a vector
106 of all the operands. */
108 printf (" PATTERN (ins1) = gen_rtx_PARALLEL (VOIDmode, gen_rtvec_v (%d, operands));\n", n_operands);
110 /* Record this define_peephole's insn code in the insn,
111 as if it had been recognized to match this. */
112 printf (" INSN_CODE (ins1) = %d;\n",
115 /* Delete the remaining insns. */
117 printf (" delete_for_peephole (NEXT_INSN (ins1), insn);\n");
119 /* See reload1.c for insertion of NOTE which guarantees that this
121 printf (" return NEXT_INSN (insn);\n");
123 printf (" L%d:\n\n", insn_code_number);
127 match_rtx (rtx x, struct link *path, int fail_label)
144 if (XINT (x, 0) > max_opno)
145 max_opno = XINT (x, 0);
146 if (XINT (x, 0) >= n_operands)
147 n_operands = 1 + XINT (x, 0);
153 printf (" operands[%d] = x;\n", XINT (x, 0));
154 if (XSTR (x, 1) && XSTR (x, 1)[0])
155 printf (" if (! %s (x, %smode)) goto L%d;\n",
156 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
165 printf (" if (!rtx_equal_p (operands[%d], x)) goto L%d;\n",
166 XINT (x, 0), fail_label);
174 printf (" if (GET_CODE (operands[%d]) != GET_CODE (x)\n", XINT (x, 0));
175 printf (" || GET_MODE (operands[%d]) != GET_MODE (x)) goto L%d;\n",
176 XINT (x, 0), fail_label);
177 printf (" operands[%d] = x;\n", XINT (x, 0));
180 for (i = 0; i < XVECLEN (x, 1); i++)
183 match_rtx (XVECEXP (x, 1, i), &link, fail_label);
188 if (XINT (x, 0) > max_opno)
189 max_opno = XINT (x, 0);
190 if (XINT (x, 0) >= n_operands)
191 n_operands = 1 + XINT (x, 0);
197 printf (" operands[%d] = x;\n", XINT (x, 0));
198 if (XSTR (x, 1) && XSTR (x, 1)[0])
199 printf (" if (! %s (x, %smode)) goto L%d;\n",
200 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
203 for (i = 0; i < XVECLEN (x, 2); i++)
206 match_rtx (XVECEXP (x, 2, i), &link, fail_label);
211 if (XINT (x, 0) > max_opno)
212 max_opno = XINT (x, 0);
213 if (XINT (x, 0) >= n_operands)
214 n_operands = 1 + XINT (x, 0);
220 printf (" if (GET_CODE (x) != PARALLEL) goto L%d;\n", fail_label);
221 printf (" operands[%d] = x;\n", XINT (x, 0));
222 if (XSTR (x, 1) && XSTR (x, 1)[0])
223 printf (" if (! %s (x, %smode)) goto L%d;\n",
224 XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
227 for (i = 0; i < XVECLEN (x, 2); i++)
230 match_rtx (XVECEXP (x, 2, i), &link, fail_label);
235 match_rtx (XEXP (x, 0), path, fail_label);
246 printf (" if (GET_CODE (x) != ");
248 printf (") goto L%d;\n", fail_label);
250 if (GET_MODE (x) != VOIDmode)
252 printf (" if (GET_MODE (x) != %smode) goto L%d;\n",
253 GET_MODE_NAME (GET_MODE (x)), fail_label);
258 fmt = GET_RTX_FORMAT (code);
259 len = GET_RTX_LENGTH (code);
260 for (i = 0; i < len; i++)
263 if (fmt[i] == 'e' || fmt[i] == 'u')
264 match_rtx (XEXP (x, i), &link, fail_label);
265 else if (fmt[i] == 'E')
268 printf (" if (XVECLEN (x, %d) != %d) goto L%d;\n",
269 i, XVECLEN (x, i), fail_label);
270 for (j = 0; j < XVECLEN (x, i); j++)
273 match_rtx (XVECEXP (x, i, j), &link, fail_label);
276 else if (fmt[i] == 'i')
278 /* Make sure that at run time `x' is the RTX we want to test. */
286 printf (" if (XINT (x, %d) != %d) goto L%d;\n",
287 i, XINT (x, i), fail_label);
289 else if (fmt[i] == 'w')
291 /* Make sure that at run time `x' is the RTX we want to test. */
299 printf (" if (XWINT (x, %d) != ", i);
300 printf (HOST_WIDE_INT_PRINT_DEC, XWINT (x, i));
301 printf (") goto L%d;\n", fail_label);
303 else if (fmt[i] == 's')
305 /* Make sure that at run time `x' is the RTX we want to test. */
313 printf (" if (strcmp (XSTR (x, %d), \"%s\")) goto L%d;\n",
314 i, XSTR (x, i), fail_label);
319 /* Given a PATH, representing a path down the instruction's
320 pattern from the root to a certain point, output code to
321 evaluate to the rtx at that point. */
324 print_path (struct link *path)
328 else if (path->vecelt >= 0)
330 printf ("XVECEXP (");
331 print_path (path->next);
332 printf (", %d, %d)", path->pos, path->vecelt);
337 print_path (path->next);
338 printf (", %d)", path->pos);
343 print_code (RTX_CODE code)
346 for (p1 = GET_RTX_NAME (code); *p1; p1++)
347 putchar (TOUPPER(*p1));
350 extern int main (int, char **);
353 main (int argc, char **argv)
359 progname = "genpeep";
361 if (init_md_reader_args (argc, argv) != SUCCESS_EXIT_CODE)
362 return (FATAL_EXIT_CODE);
364 printf ("/* Generated automatically by the program `genpeep'\n\
365 from the machine description file `md'. */\n\n");
367 printf ("#include \"config.h\"\n");
368 printf ("#include \"system.h\"\n");
369 printf ("#include \"coretypes.h\"\n");
370 printf ("#include \"tm.h\"\n");
371 printf ("#include \"insn-config.h\"\n");
372 printf ("#include \"rtl.h\"\n");
373 printf ("#include \"tm_p.h\"\n");
374 printf ("#include \"regs.h\"\n");
375 printf ("#include \"output.h\"\n");
376 printf ("#include \"real.h\"\n");
377 printf ("#include \"recog.h\"\n");
378 printf ("#include \"except.h\"\n");
379 printf ("#include \"function.h\"\n");
380 printf ("#include \"toplev.h\"\n");
381 printf ("#include \"flags.h\"\n");
382 printf ("#include \"tm-constrs.h\"\n\n");
384 printf ("#ifdef HAVE_peephole\n");
385 printf ("extern rtx peep_operand[];\n\n");
386 printf ("#define operands peep_operand\n\n");
388 printf ("rtx\npeephole (rtx ins1)\n{\n");
389 printf (" rtx insn ATTRIBUTE_UNUSED, x ATTRIBUTE_UNUSED, pat ATTRIBUTE_UNUSED;\n\n");
391 /* Early out: no peepholes for insns followed by barriers. */
392 printf (" if (NEXT_INSN (ins1)\n");
393 printf (" && BARRIER_P (NEXT_INSN (ins1)))\n");
394 printf (" return 0;\n\n");
396 /* Read the machine description. */
400 int line_no, rtx_number = 0;
402 desc = read_md_rtx (&line_no, &rtx_number);
406 if (GET_CODE (desc) == DEFINE_PEEPHOLE)
411 if (GET_CODE (desc) == DEFINE_INSN
412 || GET_CODE (desc) == DEFINE_EXPAND
413 || GET_CODE (desc) == DEFINE_SPLIT
414 || GET_CODE (desc) == DEFINE_PEEPHOLE2)
420 printf (" return 0;\n}\n\n");
425 printf ("rtx peep_operand[%d];\n", max_opno + 1);
429 return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);