1 /* Generate code from machine description to perform peephole optimizations.
2 Copyright (C) 1987, 89, 92, 97, 98, 1999 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 void fatal
PVPROTO ((const char *, ...))
50 ATTRIBUTE_PRINTF_1 ATTRIBUTE_NORETURN
;
51 void fancy_abort
PROTO((void)) ATTRIBUTE_NORETURN
;
55 /* Number of operands used in current peephole definition. */
57 static int n_operands
;
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. */
62 static int insn_code_number
= 0;
64 static void gen_peephole
PROTO((rtx
));
65 static void match_rtx
PROTO((rtx
, struct link
*, int));
66 static void print_path
PROTO((struct link
*));
67 static void print_code
PROTO((RTX_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
);
276 printf (" if (GET_CODE (x) != ");
278 printf (") goto L%d;\n", fail_label
);
280 if (GET_MODE (x
) != VOIDmode
)
282 printf (" if (GET_MODE (x) != %smode) goto L%d;\n",
283 GET_MODE_NAME (GET_MODE (x
)), fail_label
);
288 fmt
= GET_RTX_FORMAT (code
);
289 len
= GET_RTX_LENGTH (code
);
290 for (i
= 0; i
< len
; i
++)
293 if (fmt
[i
] == 'e' || fmt
[i
] == 'u')
294 match_rtx (XEXP (x
, i
), &link
, fail_label
);
295 else if (fmt
[i
] == 'E')
298 printf (" if (XVECLEN (x, %d) != %d) goto L%d;\n",
299 i
, XVECLEN (x
, i
), fail_label
);
300 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
303 match_rtx (XVECEXP (x
, i
, j
), &link
, fail_label
);
306 else if (fmt
[i
] == 'i')
308 /* Make sure that at run time `x' is the RTX we want to test. */
316 printf (" if (XINT (x, %d) != %d) goto L%d;\n",
317 i
, XINT (x
, i
), fail_label
);
319 else if (fmt
[i
] == 'w')
321 /* Make sure that at run time `x' is the RTX we want to test. */
329 printf (" if (XWINT (x, %d) != ", i
);
330 printf (HOST_WIDE_INT_PRINT_DEC
, XWINT (x
, i
));
331 printf (") goto L%d;\n", fail_label
);
333 else if (fmt
[i
] == 's')
335 /* Make sure that at run time `x' is the RTX we want to test. */
343 printf (" if (strcmp (XSTR (x, %d), \"%s\")) goto L%d;\n",
344 i
, XSTR (x
, i
), fail_label
);
349 /* Given a PATH, representing a path down the instruction's
350 pattern from the root to a certain point, output code to
351 evaluate to the rtx at that point. */
359 else if (path
->vecelt
>= 0)
361 printf ("XVECEXP (");
362 print_path (path
->next
);
363 printf (", %d, %d)", path
->pos
, path
->vecelt
);
368 print_path (path
->next
);
369 printf (", %d)", path
->pos
);
378 for (p1
= GET_RTX_NAME (code
); *p1
; p1
++)
380 if (*p1
>= 'a' && *p1
<= 'z')
381 putchar (*p1
+ 'A' - 'a');
391 register PTR val
= (PTR
) malloc (size
);
394 fatal ("virtual memory exhausted");
405 ptr
= (PTR
) realloc (old
, size
);
407 ptr
= (PTR
) malloc (size
);
409 fatal ("virtual memory exhausted");
414 fatal
VPROTO ((const char *format
, ...))
416 #ifndef ANSI_PROTOTYPES
421 VA_START (ap
, format
);
423 #ifndef ANSI_PROTOTYPES
424 format
= va_arg (ap
, const char *);
427 fprintf (stderr
, "genpeep: ");
428 vfprintf (stderr
, format
, ap
);
430 fprintf (stderr
, "\n");
431 exit (FATAL_EXIT_CODE
);
434 /* More 'friendly' abort that prints the line and file.
435 config.h can #define abort fancy_abort if you like that sort of thing. */
440 fatal ("Internal gcc abort.");
454 obstack_init (rtl_obstack
);
457 fatal ("No input file name.");
459 infile
= fopen (argv
[1], "r");
463 exit (FATAL_EXIT_CODE
);
468 printf ("/* Generated automatically by the program `genpeep'\n\
469 from the machine description file `md'. */\n\n");
471 printf ("#include \"config.h\"\n");
472 printf ("#include \"system.h\"\n");
473 printf ("#include \"insn-config.h\"\n");
474 printf ("#include \"rtl.h\"\n");
475 printf ("#include \"regs.h\"\n");
476 printf ("#include \"output.h\"\n");
477 printf ("#include \"real.h\"\n");
478 printf ("#include \"recog.h\"\n");
479 printf ("#include \"except.h\"\n\n");
481 printf ("extern rtx peep_operand[];\n\n");
482 printf ("#define operands peep_operand\n\n");
484 printf ("rtx\npeephole (ins1)\n rtx ins1;\n{\n");
485 printf (" rtx insn ATTRIBUTE_UNUSED, x ATTRIBUTE_UNUSED, pat ATTRIBUTE_UNUSED;\n\n");
487 /* Early out: no peepholes for insns followed by barriers. */
488 printf (" if (NEXT_INSN (ins1)\n");
489 printf (" && GET_CODE (NEXT_INSN (ins1)) == BARRIER)\n");
490 printf (" return 0;\n\n");
492 /* Read the machine description. */
496 c
= read_skip_spaces (infile
);
501 desc
= read_rtx (infile
);
502 if (GET_CODE (desc
) == DEFINE_PEEPHOLE
)
507 if (GET_CODE (desc
) == DEFINE_INSN
508 || GET_CODE (desc
) == DEFINE_EXPAND
509 || GET_CODE (desc
) == DEFINE_SPLIT
)
515 printf (" return 0;\n}\n\n");
520 printf ("rtx peep_operand[%d];\n", max_opno
+ 1);
523 exit (ferror (stdout
) != 0 ? FATAL_EXIT_CODE
: SUCCESS_EXIT_CODE
);