xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/genemit.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /* Generate code from machine description to emit insns as rtl.
2    Copyright (C) 1987, 1988, 1991, 1994, 1995, 1997, 1998, 1999, 2000, 2001,
3    2003, 2004, 2005, 2007, 2008, 2009 Free Software Foundation, Inc.
4 
5 This file is part of GCC.
6 
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
10 version.
11 
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
15 for more details.
16 
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/>.  */
20 
21 
22 #include "bconfig.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tm.h"
26 #include "rtl.h"
27 #include "errors.h"
28 #include "gensupport.h"
29 
30 
31 static int max_opno;
32 static int max_dup_opno;
33 static int max_scratch_opno;
34 static int insn_code_number;
35 static int insn_index_number;
36 
37 /* Data structure for recording the patterns of insns that have CLOBBERs.
38    We use this to output a function that adds these CLOBBERs to a
39    previously-allocated PARALLEL expression.  */
40 
41 struct clobber_pat
42 {
43   struct clobber_ent *insns;
44   rtx pattern;
45   int first_clobber;
46   struct clobber_pat *next;
47   int has_hard_reg;
48 } *clobber_list;
49 
50 /* Records one insn that uses the clobber list.  */
51 
52 struct clobber_ent
53 {
54   int code_number;		/* Counts only insns.  */
55   struct clobber_ent *next;
56 };
57 
58 static void max_operand_1		(rtx);
59 static int max_operand_vec		(rtx, int);
60 static void print_code			(RTX_CODE);
61 static void gen_exp			(rtx, enum rtx_code, char *);
62 static void gen_insn			(rtx, int);
63 static void gen_expand			(rtx);
64 static void gen_split			(rtx);
65 static void output_add_clobbers		(void);
66 static void output_added_clobbers_hard_reg_p (void);
67 static void gen_rtx_scratch		(rtx, enum rtx_code);
68 static void output_peephole2_scratches	(rtx);
69 
70 
71 static void
72 max_operand_1 (rtx x)
73 {
74   RTX_CODE code;
75   int i;
76   int len;
77   const char *fmt;
78 
79   if (x == 0)
80     return;
81 
82   code = GET_CODE (x);
83 
84   if (code == MATCH_OPERAND || code == MATCH_OPERATOR
85       || code == MATCH_PARALLEL)
86     max_opno = MAX (max_opno, XINT (x, 0));
87   if (code == MATCH_DUP || code == MATCH_OP_DUP || code == MATCH_PAR_DUP)
88     max_dup_opno = MAX (max_dup_opno, XINT (x, 0));
89   if (code == MATCH_SCRATCH)
90     max_scratch_opno = MAX (max_scratch_opno, XINT (x, 0));
91 
92   fmt = GET_RTX_FORMAT (code);
93   len = GET_RTX_LENGTH (code);
94   for (i = 0; i < len; i++)
95     {
96       if (fmt[i] == 'e' || fmt[i] == 'u')
97 	max_operand_1 (XEXP (x, i));
98       else if (fmt[i] == 'E')
99 	{
100 	  int j;
101 	  for (j = 0; j < XVECLEN (x, i); j++)
102 	    max_operand_1 (XVECEXP (x, i, j));
103 	}
104     }
105 }
106 
107 static int
108 max_operand_vec (rtx insn, int arg)
109 {
110   int len = XVECLEN (insn, arg);
111   int i;
112 
113   max_opno = -1;
114   max_dup_opno = -1;
115   max_scratch_opno = -1;
116 
117   for (i = 0; i < len; i++)
118     max_operand_1 (XVECEXP (insn, arg, i));
119 
120   return max_opno + 1;
121 }
122 
123 static void
124 print_code (RTX_CODE code)
125 {
126   const char *p1;
127   for (p1 = GET_RTX_NAME (code); *p1; p1++)
128     putchar (TOUPPER(*p1));
129 }
130 
131 static void
132 gen_rtx_scratch (rtx x, enum rtx_code subroutine_type)
133 {
134   if (subroutine_type == DEFINE_PEEPHOLE2)
135     {
136       printf ("operand%d", XINT (x, 0));
137     }
138   else
139     {
140       printf ("gen_rtx_SCRATCH (%smode)", GET_MODE_NAME (GET_MODE (x)));
141     }
142 }
143 
144 /* Print a C expression to construct an RTX just like X,
145    substituting any operand references appearing within.  */
146 
147 static void
148 gen_exp (rtx x, enum rtx_code subroutine_type, char *used)
149 {
150   RTX_CODE code;
151   int i;
152   int len;
153   const char *fmt;
154 
155   if (x == 0)
156     {
157       printf ("NULL_RTX");
158       return;
159     }
160 
161   code = GET_CODE (x);
162 
163   switch (code)
164     {
165     case MATCH_OPERAND:
166     case MATCH_DUP:
167       if (used)
168 	{
169 	  if (used[XINT (x, 0)])
170 	    {
171 	      printf ("copy_rtx (operand%d)", XINT (x, 0));
172 	      return;
173 	    }
174 	  used[XINT (x, 0)] = 1;
175 	}
176       printf ("operand%d", XINT (x, 0));
177       return;
178 
179     case MATCH_OP_DUP:
180       printf ("gen_rtx_fmt_");
181       for (i = 0; i < XVECLEN (x, 1); i++)
182 	printf ("e");
183       printf (" (GET_CODE (operand%d), ", XINT (x, 0));
184       if (GET_MODE (x) == VOIDmode)
185 	printf ("GET_MODE (operand%d)", XINT (x, 0));
186       else
187 	printf ("%smode", GET_MODE_NAME (GET_MODE (x)));
188       for (i = 0; i < XVECLEN (x, 1); i++)
189 	{
190 	  printf (",\n\t\t");
191 	  gen_exp (XVECEXP (x, 1, i), subroutine_type, used);
192 	}
193       printf (")");
194       return;
195 
196     case MATCH_OPERATOR:
197       printf ("gen_rtx_fmt_");
198       for (i = 0; i < XVECLEN (x, 2); i++)
199 	printf ("e");
200       printf (" (GET_CODE (operand%d)", XINT (x, 0));
201       printf (", %smode", GET_MODE_NAME (GET_MODE (x)));
202       for (i = 0; i < XVECLEN (x, 2); i++)
203 	{
204 	  printf (",\n\t\t");
205 	  gen_exp (XVECEXP (x, 2, i), subroutine_type, used);
206 	}
207       printf (")");
208       return;
209 
210     case MATCH_PARALLEL:
211     case MATCH_PAR_DUP:
212       printf ("operand%d", XINT (x, 0));
213       return;
214 
215     case MATCH_SCRATCH:
216       gen_rtx_scratch (x, subroutine_type);
217       return;
218 
219     case ADDRESS:
220       fatal ("ADDRESS expression code used in named instruction pattern");
221 
222     case PC:
223       printf ("pc_rtx");
224       return;
225     case CLOBBER:
226       if (REG_P (XEXP (x, 0)))
227 	{
228 	  printf ("gen_hard_reg_clobber (%smode, %i)", GET_MODE_NAME (GET_MODE (XEXP (x, 0))),
229 			  			     REGNO (XEXP (x, 0)));
230 	  return;
231 	}
232       break;
233 
234     case CC0:
235       printf ("cc0_rtx");
236       return;
237 
238     case CONST_INT:
239       if (INTVAL (x) == 0)
240 	printf ("const0_rtx");
241       else if (INTVAL (x) == 1)
242 	printf ("const1_rtx");
243       else if (INTVAL (x) == -1)
244 	printf ("constm1_rtx");
245       else if (-MAX_SAVED_CONST_INT <= INTVAL (x)
246 	  && INTVAL (x) <= MAX_SAVED_CONST_INT)
247 	printf ("const_int_rtx[MAX_SAVED_CONST_INT + (%d)]",
248 		(int) INTVAL (x));
249       else if (INTVAL (x) == STORE_FLAG_VALUE)
250 	printf ("const_true_rtx");
251       else
252 	{
253 	  printf ("GEN_INT (HOST_WIDE_INT_CONSTANT (");
254 	  printf (HOST_WIDE_INT_PRINT_DEC, INTVAL (x));
255 	  printf ("))");
256 	}
257       return;
258 
259     case CONST_DOUBLE:
260     case CONST_FIXED:
261       /* These shouldn't be written in MD files.  Instead, the appropriate
262 	 routines in varasm.c should be called.  */
263       gcc_unreachable ();
264 
265     default:
266       break;
267     }
268 
269   printf ("gen_rtx_");
270   print_code (code);
271   printf (" (%smode", GET_MODE_NAME (GET_MODE (x)));
272 
273   fmt = GET_RTX_FORMAT (code);
274   len = GET_RTX_LENGTH (code);
275   for (i = 0; i < len; i++)
276     {
277       if (fmt[i] == '0')
278 	break;
279       printf (",\n\t");
280       switch (fmt[i])
281 	{
282 	case 'e': case 'u':
283 	  gen_exp (XEXP (x, i), subroutine_type, used);
284 	  break;
285 
286 	case 'i':
287 	  printf ("%u", XINT (x, i));
288 	  break;
289 
290 	case 's':
291 	  printf ("\"%s\"", XSTR (x, i));
292 	  break;
293 
294 	case 'E':
295 	  {
296 	    int j;
297 	    printf ("gen_rtvec (%d", XVECLEN (x, i));
298 	    for (j = 0; j < XVECLEN (x, i); j++)
299 	      {
300 		printf (",\n\t\t");
301 		gen_exp (XVECEXP (x, i, j), subroutine_type, used);
302 	      }
303 	    printf (")");
304 	    break;
305 	  }
306 
307 	default:
308 	  gcc_unreachable ();
309 	}
310     }
311   printf (")");
312 }
313 
314 /* Generate the `gen_...' function for a DEFINE_INSN.  */
315 
316 static void
317 gen_insn (rtx insn, int lineno)
318 {
319   int operands;
320   int i;
321 
322   /* See if the pattern for this insn ends with a group of CLOBBERs of (hard)
323      registers or MATCH_SCRATCHes.  If so, store away the information for
324      later.  */
325 
326   if (XVEC (insn, 1))
327     {
328       int has_hard_reg = 0;
329 
330       for (i = XVECLEN (insn, 1) - 1; i > 0; i--)
331 	{
332 	  if (GET_CODE (XVECEXP (insn, 1, i)) != CLOBBER)
333 	    break;
334 
335 	  if (REG_P (XEXP (XVECEXP (insn, 1, i), 0)))
336 	    has_hard_reg = 1;
337 	  else if (GET_CODE (XEXP (XVECEXP (insn, 1, i), 0)) != MATCH_SCRATCH)
338 	    break;
339 	}
340 
341       if (i != XVECLEN (insn, 1) - 1)
342 	{
343 	  struct clobber_pat *p;
344 	  struct clobber_ent *link = XNEW (struct clobber_ent);
345 	  int j;
346 
347 	  link->code_number = insn_code_number;
348 
349 	  /* See if any previous CLOBBER_LIST entry is the same as this
350 	     one.  */
351 
352 	  for (p = clobber_list; p; p = p->next)
353 	    {
354 	      if (p->first_clobber != i + 1
355 		  || XVECLEN (p->pattern, 1) != XVECLEN (insn, 1))
356 		continue;
357 
358 	      for (j = i + 1; j < XVECLEN (insn, 1); j++)
359 		{
360 		  rtx old_rtx = XEXP (XVECEXP (p->pattern, 1, j), 0);
361 		  rtx new_rtx = XEXP (XVECEXP (insn, 1, j), 0);
362 
363 		  /* OLD and NEW_INSN are the same if both are to be a SCRATCH
364 		     of the same mode,
365 		     or if both are registers of the same mode and number.  */
366 		  if (! (GET_MODE (old_rtx) == GET_MODE (new_rtx)
367 			 && ((GET_CODE (old_rtx) == MATCH_SCRATCH
368 			      && GET_CODE (new_rtx) == MATCH_SCRATCH)
369 			     || (REG_P (old_rtx) && REG_P (new_rtx)
370 				 && REGNO (old_rtx) == REGNO (new_rtx)))))
371 		    break;
372 		}
373 
374 	      if (j == XVECLEN (insn, 1))
375 		break;
376 	    }
377 
378 	  if (p == 0)
379 	    {
380 	      p = XNEW (struct clobber_pat);
381 
382 	      p->insns = 0;
383 	      p->pattern = insn;
384 	      p->first_clobber = i + 1;
385 	      p->next = clobber_list;
386 	      p->has_hard_reg = has_hard_reg;
387 	      clobber_list = p;
388 	    }
389 
390 	  link->next = p->insns;
391 	  p->insns = link;
392 	}
393     }
394 
395   /* Don't mention instructions whose names are the null string
396      or begin with '*'.  They are in the machine description just
397      to be recognized.  */
398   if (XSTR (insn, 0)[0] == 0 || XSTR (insn, 0)[0] == '*')
399     return;
400 
401   printf ("/* %s:%d */\n", read_rtx_filename, lineno);
402 
403   /* Find out how many operands this function has.  */
404   operands = max_operand_vec (insn, 1);
405   if (max_dup_opno >= operands)
406     fatal ("match_dup operand number has no match_operand");
407 
408   /* Output the function name and argument declarations.  */
409   printf ("rtx\ngen_%s (", XSTR (insn, 0));
410   if (operands)
411     for (i = 0; i < operands; i++)
412       if (i)
413 	printf (",\n\trtx operand%d ATTRIBUTE_UNUSED", i);
414       else
415 	printf ("rtx operand%d ATTRIBUTE_UNUSED", i);
416   else
417     printf ("void");
418   printf (")\n");
419   printf ("{\n");
420 
421   /* Output code to construct and return the rtl for the instruction body.  */
422 
423   if (XVECLEN (insn, 1) == 1)
424     {
425       printf ("  return ");
426       gen_exp (XVECEXP (insn, 1, 0), DEFINE_INSN, NULL);
427       printf (";\n}\n\n");
428     }
429   else
430     {
431       char *used = XCNEWVEC (char, operands);
432 
433       printf ("  return gen_rtx_PARALLEL (VOIDmode, gen_rtvec (%d",
434 	      XVECLEN (insn, 1));
435 
436       for (i = 0; i < XVECLEN (insn, 1); i++)
437 	{
438 	  printf (",\n\t\t");
439 	  gen_exp (XVECEXP (insn, 1, i), DEFINE_INSN, used);
440 	}
441       printf ("));\n}\n\n");
442       XDELETEVEC (used);
443     }
444 }
445 
446 /* Generate the `gen_...' function for a DEFINE_EXPAND.  */
447 
448 static void
449 gen_expand (rtx expand)
450 {
451   int operands;
452   int i;
453   char *used;
454 
455   if (strlen (XSTR (expand, 0)) == 0)
456     fatal ("define_expand lacks a name");
457   if (XVEC (expand, 1) == 0)
458     fatal ("define_expand for %s lacks a pattern", XSTR (expand, 0));
459 
460   /* Find out how many operands this function has.  */
461   operands = max_operand_vec (expand, 1);
462 
463   /* Output the function name and argument declarations.  */
464   printf ("rtx\ngen_%s (", XSTR (expand, 0));
465   if (operands)
466     for (i = 0; i < operands; i++)
467       if (i)
468 	printf (",\n\trtx operand%d", i);
469       else
470 	printf ("rtx operand%d", i);
471   else
472     printf ("void");
473   printf (")\n");
474   printf ("{\n");
475 
476   /* If we don't have any C code to write, only one insn is being written,
477      and no MATCH_DUPs are present, we can just return the desired insn
478      like we do for a DEFINE_INSN.  This saves memory.  */
479   if ((XSTR (expand, 3) == 0 || *XSTR (expand, 3) == '\0')
480       && operands > max_dup_opno
481       && XVECLEN (expand, 1) == 1)
482     {
483       printf ("  return ");
484       gen_exp (XVECEXP (expand, 1, 0), DEFINE_EXPAND, NULL);
485       printf (";\n}\n\n");
486       return;
487     }
488 
489   /* For each operand referred to only with MATCH_DUPs,
490      make a local variable.  */
491   for (i = operands; i <= max_dup_opno; i++)
492     printf ("  rtx operand%d;\n", i);
493   for (; i <= max_scratch_opno; i++)
494     printf ("  rtx operand%d ATTRIBUTE_UNUSED;\n", i);
495   printf ("  rtx _val = 0;\n");
496   printf ("  start_sequence ();\n");
497 
498   /* The fourth operand of DEFINE_EXPAND is some code to be executed
499      before the actual construction.
500      This code expects to refer to `operands'
501      just as the output-code in a DEFINE_INSN does,
502      but here `operands' is an automatic array.
503      So copy the operand values there before executing it.  */
504   if (XSTR (expand, 3) && *XSTR (expand, 3))
505     {
506       printf ("  {\n");
507       if (operands > 0 || max_dup_opno >= 0 || max_scratch_opno >= 0)
508 	printf ("    rtx operands[%d];\n",
509 	    MAX (operands, MAX (max_scratch_opno, max_dup_opno) + 1));
510       /* Output code to copy the arguments into `operands'.  */
511       for (i = 0; i < operands; i++)
512 	printf ("    operands[%d] = operand%d;\n", i, i);
513 
514       /* Output the special code to be executed before the sequence
515 	 is generated.  */
516       print_rtx_ptr_loc (XSTR (expand, 3));
517       printf ("%s\n", XSTR (expand, 3));
518 
519       /* Output code to copy the arguments back out of `operands'
520 	 (unless we aren't going to use them at all).  */
521       if (XVEC (expand, 1) != 0)
522 	{
523 	  for (i = 0; i < operands; i++)
524 	    printf ("    operand%d = operands[%d];\n", i, i);
525 	  for (; i <= max_dup_opno; i++)
526 	    printf ("    operand%d = operands[%d];\n", i, i);
527 	  for (; i <= max_scratch_opno; i++)
528 	    printf ("    operand%d = operands[%d];\n", i, i);
529 	}
530       printf ("  }\n");
531     }
532 
533   /* Output code to construct the rtl for the instruction bodies.
534      Use emit_insn to add them to the sequence being accumulated.
535      But don't do this if the user's code has set `no_more' nonzero.  */
536 
537   used = XCNEWVEC (char,
538 		   MAX (operands, MAX (max_scratch_opno, max_dup_opno) + 1));
539 
540   for (i = 0; i < XVECLEN (expand, 1); i++)
541     {
542       rtx next = XVECEXP (expand, 1, i);
543       if ((GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC)
544 	  || (GET_CODE (next) == PARALLEL
545 	      && ((GET_CODE (XVECEXP (next, 0, 0)) == SET
546 		   && GET_CODE (SET_DEST (XVECEXP (next, 0, 0))) == PC)
547 		  || GET_CODE (XVECEXP (next, 0, 0)) == RETURN))
548 	  || GET_CODE (next) == RETURN)
549 	printf ("  emit_jump_insn (");
550       else if ((GET_CODE (next) == SET && GET_CODE (SET_SRC (next)) == CALL)
551 	       || GET_CODE (next) == CALL
552 	       || (GET_CODE (next) == PARALLEL
553 		   && GET_CODE (XVECEXP (next, 0, 0)) == SET
554 		   && GET_CODE (SET_SRC (XVECEXP (next, 0, 0))) == CALL)
555 	       || (GET_CODE (next) == PARALLEL
556 		   && GET_CODE (XVECEXP (next, 0, 0)) == CALL))
557 	printf ("  emit_call_insn (");
558       else if (LABEL_P (next))
559 	printf ("  emit_label (");
560       else if (GET_CODE (next) == MATCH_OPERAND
561 	       || GET_CODE (next) == MATCH_DUP
562 	       || GET_CODE (next) == MATCH_OPERATOR
563 	       || GET_CODE (next) == MATCH_OP_DUP
564 	       || GET_CODE (next) == MATCH_PARALLEL
565 	       || GET_CODE (next) == MATCH_PAR_DUP
566 	       || GET_CODE (next) == PARALLEL)
567 	printf ("  emit (");
568       else
569 	printf ("  emit_insn (");
570       gen_exp (next, DEFINE_EXPAND, used);
571       printf (");\n");
572       if (GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC
573 	  && GET_CODE (SET_SRC (next)) == LABEL_REF)
574 	printf ("  emit_barrier ();");
575     }
576 
577   XDELETEVEC (used);
578 
579   /* Call `get_insns' to extract the list of all the
580      insns emitted within this gen_... function.  */
581 
582   printf ("  _val = get_insns ();\n");
583   printf ("  end_sequence ();\n");
584   printf ("  return _val;\n}\n\n");
585 }
586 
587 /* Like gen_expand, but generates insns resulting from splitting SPLIT.  */
588 
589 static void
590 gen_split (rtx split)
591 {
592   int i;
593   int operands;
594   const char *const name =
595     ((GET_CODE (split) == DEFINE_PEEPHOLE2) ? "peephole2" : "split");
596   const char *unused;
597   char *used;
598 
599   if (XVEC (split, 0) == 0)
600     fatal ("define_%s (definition %d) lacks a pattern", name,
601 	   insn_index_number);
602   else if (XVEC (split, 2) == 0)
603     fatal ("define_%s (definition %d) lacks a replacement pattern", name,
604 	   insn_index_number);
605 
606   /* Find out how many operands this function has.  */
607 
608   max_operand_vec (split, 2);
609   operands = MAX (max_opno, MAX (max_dup_opno, max_scratch_opno)) + 1;
610   unused = (operands == 0 ? " ATTRIBUTE_UNUSED" : "");
611   used = XCNEWVEC (char, operands);
612 
613   /* Output the prototype, function name and argument declarations.  */
614   if (GET_CODE (split) == DEFINE_PEEPHOLE2)
615     {
616       printf ("extern rtx gen_%s_%d (rtx, rtx *);\n",
617 	      name, insn_code_number);
618       printf ("rtx\ngen_%s_%d (rtx curr_insn ATTRIBUTE_UNUSED, rtx *operands%s)\n",
619 	      name, insn_code_number, unused);
620     }
621   else
622     {
623       printf ("extern rtx gen_split_%d (rtx, rtx *);\n", insn_code_number);
624       printf ("rtx\ngen_split_%d (rtx curr_insn ATTRIBUTE_UNUSED, rtx *operands%s)\n",
625 	      insn_code_number, unused);
626     }
627   printf ("{\n");
628 
629   /* Declare all local variables.  */
630   for (i = 0; i < operands; i++)
631     printf ("  rtx operand%d;\n", i);
632   printf ("  rtx _val = 0;\n");
633 
634   if (GET_CODE (split) == DEFINE_PEEPHOLE2)
635     output_peephole2_scratches (split);
636 
637   printf ("  start_sequence ();\n");
638 
639   /* The fourth operand of DEFINE_SPLIT is some code to be executed
640      before the actual construction.  */
641 
642   if (XSTR (split, 3))
643     {
644       print_rtx_ptr_loc (XSTR (split, 3));
645       printf ("%s\n", XSTR (split, 3));
646     }
647 
648   /* Output code to copy the arguments back out of `operands'  */
649   for (i = 0; i < operands; i++)
650     printf ("  operand%d = operands[%d];\n", i, i);
651 
652   /* Output code to construct the rtl for the instruction bodies.
653      Use emit_insn to add them to the sequence being accumulated.
654      But don't do this if the user's code has set `no_more' nonzero.  */
655 
656   for (i = 0; i < XVECLEN (split, 2); i++)
657     {
658       rtx next = XVECEXP (split, 2, i);
659       if ((GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC)
660 	  || (GET_CODE (next) == PARALLEL
661 	      && GET_CODE (XVECEXP (next, 0, 0)) == SET
662 	      && GET_CODE (SET_DEST (XVECEXP (next, 0, 0))) == PC)
663 	  || GET_CODE (next) == RETURN)
664 	printf ("  emit_jump_insn (");
665       else if ((GET_CODE (next) == SET && GET_CODE (SET_SRC (next)) == CALL)
666 	       || GET_CODE (next) == CALL
667 	       || (GET_CODE (next) == PARALLEL
668 		   && GET_CODE (XVECEXP (next, 0, 0)) == SET
669 		   && GET_CODE (SET_SRC (XVECEXP (next, 0, 0))) == CALL)
670 	       || (GET_CODE (next) == PARALLEL
671 		   && GET_CODE (XVECEXP (next, 0, 0)) == CALL))
672 	printf ("  emit_call_insn (");
673       else if (LABEL_P (next))
674 	printf ("  emit_label (");
675       else if (GET_CODE (next) == MATCH_OPERAND
676 	       || GET_CODE (next) == MATCH_OPERATOR
677 	       || GET_CODE (next) == MATCH_PARALLEL
678 	       || GET_CODE (next) == MATCH_OP_DUP
679 	       || GET_CODE (next) == MATCH_DUP
680 	       || GET_CODE (next) == PARALLEL)
681 	printf ("  emit (");
682       else
683 	printf ("  emit_insn (");
684       gen_exp (next, GET_CODE (split), used);
685       printf (");\n");
686       if (GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC
687 	  && GET_CODE (SET_SRC (next)) == LABEL_REF)
688 	printf ("  emit_barrier ();");
689     }
690 
691   /* Call `get_insns' to make a list of all the
692      insns emitted within this gen_... function.  */
693 
694   printf ("  _val = get_insns ();\n");
695   printf ("  end_sequence ();\n");
696   printf ("  return _val;\n}\n\n");
697 
698   free (used);
699 }
700 
701 /* Write a function, `add_clobbers', that is given a PARALLEL of sufficient
702    size for the insn and an INSN_CODE, and inserts the required CLOBBERs at
703    the end of the vector.  */
704 
705 static void
706 output_add_clobbers (void)
707 {
708   struct clobber_pat *clobber;
709   struct clobber_ent *ent;
710   int i;
711 
712   printf ("\n\nvoid\nadd_clobbers (rtx pattern ATTRIBUTE_UNUSED, int insn_code_number)\n");
713   printf ("{\n");
714   printf ("  switch (insn_code_number)\n");
715   printf ("    {\n");
716 
717   for (clobber = clobber_list; clobber; clobber = clobber->next)
718     {
719       for (ent = clobber->insns; ent; ent = ent->next)
720 	printf ("    case %d:\n", ent->code_number);
721 
722       for (i = clobber->first_clobber; i < XVECLEN (clobber->pattern, 1); i++)
723 	{
724 	  printf ("      XVECEXP (pattern, 0, %d) = ", i);
725 	  gen_exp (XVECEXP (clobber->pattern, 1, i),
726 		   GET_CODE (clobber->pattern), NULL);
727 	  printf (";\n");
728 	}
729 
730       printf ("      break;\n\n");
731     }
732 
733   printf ("    default:\n");
734   printf ("      gcc_unreachable ();\n");
735   printf ("    }\n");
736   printf ("}\n");
737 }
738 
739 /* Write a function, `added_clobbers_hard_reg_p' that is given an insn_code
740    number that will have clobbers added (as indicated by `recog') and returns
741    1 if those include a clobber of a hard reg or 0 if all of them just clobber
742    SCRATCH.  */
743 
744 static void
745 output_added_clobbers_hard_reg_p (void)
746 {
747   struct clobber_pat *clobber;
748   struct clobber_ent *ent;
749   int clobber_p, used;
750 
751   printf ("\n\nint\nadded_clobbers_hard_reg_p (int insn_code_number)\n");
752   printf ("{\n");
753   printf ("  switch (insn_code_number)\n");
754   printf ("    {\n");
755 
756   for (clobber_p = 0; clobber_p <= 1; clobber_p++)
757     {
758       used = 0;
759       for (clobber = clobber_list; clobber; clobber = clobber->next)
760 	if (clobber->has_hard_reg == clobber_p)
761 	  for (ent = clobber->insns; ent; ent = ent->next)
762 	    {
763 	      printf ("    case %d:\n", ent->code_number);
764 	      used++;
765 	    }
766 
767       if (used)
768 	printf ("      return %d;\n\n", clobber_p);
769     }
770 
771   printf ("    default:\n");
772   printf ("      gcc_unreachable ();\n");
773   printf ("    }\n");
774   printf ("}\n");
775 }
776 
777 /* Generate code to invoke find_free_register () as needed for the
778    scratch registers used by the peephole2 pattern in SPLIT.  */
779 
780 static void
781 output_peephole2_scratches (rtx split)
782 {
783   int i;
784   int insn_nr = 0;
785   bool first = true;
786 
787   for (i = 0; i < XVECLEN (split, 0); i++)
788     {
789       rtx elt = XVECEXP (split, 0, i);
790       if (GET_CODE (elt) == MATCH_SCRATCH)
791 	{
792 	  int last_insn_nr = insn_nr;
793 	  int cur_insn_nr = insn_nr;
794 	  int j;
795 	  for (j = i + 1; j < XVECLEN (split, 0); j++)
796 	    if (GET_CODE (XVECEXP (split, 0, j)) == MATCH_DUP)
797 	      {
798 		if (XINT (XVECEXP (split, 0, j), 0) == XINT (elt, 0))
799 		  last_insn_nr = cur_insn_nr;
800 	      }
801 	    else if (GET_CODE (XVECEXP (split, 0, j)) != MATCH_SCRATCH)
802 	      cur_insn_nr++;
803 
804 	  if (first)
805 	    {
806 	      printf ("  HARD_REG_SET _regs_allocated;\n");
807 	      printf ("  CLEAR_HARD_REG_SET (_regs_allocated);\n");
808 	      first = false;
809 	    }
810 
811 	  printf ("  if ((operands[%d] = peep2_find_free_register (%d, %d, \"%s\", %smode, &_regs_allocated)) == NULL_RTX)\n\
812     return NULL;\n",
813 		  XINT (elt, 0),
814 		  insn_nr, last_insn_nr,
815 		  XSTR (elt, 1),
816 		  GET_MODE_NAME (GET_MODE (elt)));
817 
818 	}
819       else if (GET_CODE (elt) != MATCH_DUP)
820 	insn_nr++;
821     }
822 }
823 
824 int
825 main (int argc, char **argv)
826 {
827   rtx desc;
828 
829   progname = "genemit";
830 
831   if (init_md_reader_args (argc, argv) != SUCCESS_EXIT_CODE)
832     return (FATAL_EXIT_CODE);
833 
834   /* Assign sequential codes to all entries in the machine description
835      in parallel with the tables in insn-output.c.  */
836 
837   insn_code_number = 0;
838   insn_index_number = 0;
839 
840   printf ("/* Generated automatically by the program `genemit'\n\
841 from the machine description file `md'.  */\n\n");
842 
843   printf ("#include \"config.h\"\n");
844   printf ("#include \"system.h\"\n");
845   printf ("#include \"coretypes.h\"\n");
846   printf ("#include \"tm.h\"\n");
847   printf ("#include \"rtl.h\"\n");
848   printf ("#include \"tm_p.h\"\n");
849   printf ("#include \"function.h\"\n");
850   printf ("#include \"expr.h\"\n");
851   printf ("#include \"optabs.h\"\n");
852   printf ("#include \"real.h\"\n");
853   printf ("#include \"dfp.h\"\n");
854   printf ("#include \"flags.h\"\n");
855   printf ("#include \"output.h\"\n");
856   printf ("#include \"insn-config.h\"\n");
857   printf ("#include \"hard-reg-set.h\"\n");
858   printf ("#include \"recog.h\"\n");
859   printf ("#include \"resource.h\"\n");
860   printf ("#include \"reload.h\"\n");
861   printf ("#include \"toplev.h\"\n");
862   printf ("#include \"regs.h\"\n");
863   printf ("#include \"tm-constrs.h\"\n");
864   printf ("#include \"ggc.h\"\n");
865   printf ("#include \"basic-block.h\"\n");
866   printf ("#include \"integrate.h\"\n\n");
867   printf ("#define FAIL return (end_sequence (), _val)\n");
868   printf ("#define DONE return (_val = get_insns (), end_sequence (), _val)\n\n");
869 
870   /* Read the machine description.  */
871 
872   while (1)
873     {
874       int line_no;
875 
876       desc = read_md_rtx (&line_no, &insn_code_number);
877       if (desc == NULL)
878 	break;
879 
880       switch (GET_CODE (desc))
881 	{
882 	case DEFINE_INSN:
883 	  gen_insn (desc, line_no);
884 	  break;
885 
886 	case DEFINE_EXPAND:
887 	  printf ("/* %s:%d */\n", read_rtx_filename, line_no);
888 	  gen_expand (desc);
889 	  break;
890 
891 	case DEFINE_SPLIT:
892 	  printf ("/* %s:%d */\n", read_rtx_filename, line_no);
893 	  gen_split (desc);
894 	  break;
895 
896 	case DEFINE_PEEPHOLE2:
897 	  printf ("/* %s:%d */\n", read_rtx_filename, line_no);
898 	  gen_split (desc);
899 	  break;
900 
901 	default:
902 	  break;
903 	}
904       ++insn_index_number;
905     }
906 
907   /* Write out the routines to add CLOBBERs to a pattern and say whether they
908      clobber a hard reg.  */
909   output_add_clobbers ();
910   output_added_clobbers_hard_reg_p ();
911 
912   fflush (stdout);
913   return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
914 }
915