xref: /netbsd-src/external/gpl3/gcc/dist/gcc/genemit.cc (revision 2683f5b185977c9184701f18c843971cd908b00e)
1 /* Generate code from machine description to emit insns as rtl.
2    Copyright (C) 1987-2022 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10 
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3.  If not see
18 <http://www.gnu.org/licenses/>.  */
19 
20 
21 #include "bconfig.h"
22 #include "system.h"
23 #include "coretypes.h"
24 #include "tm.h"
25 #include "rtl.h"
26 #include "errors.h"
27 #include "read-md.h"
28 #include "gensupport.h"
29 
30 
31 /* Data structure for recording the patterns of insns that have CLOBBERs.
32    We use this to output a function that adds these CLOBBERs to a
33    previously-allocated PARALLEL expression.  */
34 
35 struct clobber_pat
36 {
37   struct clobber_ent *insns;
38   rtx pattern;
39   int first_clobber;
40   struct clobber_pat *next;
41   int has_hard_reg;
42 } *clobber_list;
43 
44 /* Records one insn that uses the clobber list.  */
45 
46 struct clobber_ent
47 {
48   int code_number;		/* Counts only insns.  */
49   struct clobber_ent *next;
50 };
51 
52 static void output_peephole2_scratches	(rtx);
53 
54 /* True for <X>_optab if that optab isn't allowed to fail.  */
55 static bool nofail_optabs[NUM_OPTABS];
56 
57 static void
print_code(RTX_CODE code)58 print_code (RTX_CODE code)
59 {
60   const char *p1;
61   for (p1 = GET_RTX_NAME (code); *p1; p1++)
62     putchar (TOUPPER (*p1));
63 }
64 
65 static void
gen_rtx_scratch(rtx x,enum rtx_code subroutine_type)66 gen_rtx_scratch (rtx x, enum rtx_code subroutine_type)
67 {
68   if (subroutine_type == DEFINE_PEEPHOLE2)
69     {
70       printf ("operand%d", XINT (x, 0));
71     }
72   else
73     {
74       printf ("gen_rtx_SCRATCH (%smode)", GET_MODE_NAME (GET_MODE (x)));
75     }
76 }
77 
78 /* Print a C expression to construct an RTX just like X,
79    substituting any operand references appearing within.  */
80 
81 static void
gen_exp(rtx x,enum rtx_code subroutine_type,char * used,md_rtx_info * info)82 gen_exp (rtx x, enum rtx_code subroutine_type, char *used, md_rtx_info *info)
83 {
84   RTX_CODE code;
85   int i;
86   int len;
87   const char *fmt;
88   const char *sep = "";
89 
90   if (x == 0)
91     {
92       printf ("NULL_RTX");
93       return;
94     }
95 
96   code = GET_CODE (x);
97 
98   switch (code)
99     {
100     case MATCH_OPERAND:
101     case MATCH_DUP:
102       if (used)
103 	{
104 	  if (used[XINT (x, 0)])
105 	    {
106 	      printf ("copy_rtx (operand%d)", XINT (x, 0));
107 	      return;
108 	    }
109 	  used[XINT (x, 0)] = 1;
110 	}
111       printf ("operand%d", XINT (x, 0));
112       return;
113 
114     case MATCH_OP_DUP:
115       printf ("gen_rtx_fmt_");
116       for (i = 0; i < XVECLEN (x, 1); i++)
117 	printf ("e");
118       printf (" (GET_CODE (operand%d), ", XINT (x, 0));
119       if (GET_MODE (x) == VOIDmode)
120 	printf ("GET_MODE (operand%d)", XINT (x, 0));
121       else
122 	printf ("%smode", GET_MODE_NAME (GET_MODE (x)));
123       for (i = 0; i < XVECLEN (x, 1); i++)
124 	{
125 	  printf (",\n\t\t");
126 	  gen_exp (XVECEXP (x, 1, i), subroutine_type, used, info);
127 	}
128       printf (")");
129       return;
130 
131     case MATCH_OPERATOR:
132       printf ("gen_rtx_fmt_");
133       for (i = 0; i < XVECLEN (x, 2); i++)
134 	printf ("e");
135       printf (" (GET_CODE (operand%d)", XINT (x, 0));
136       printf (", %smode", GET_MODE_NAME (GET_MODE (x)));
137       for (i = 0; i < XVECLEN (x, 2); i++)
138 	{
139 	  printf (",\n\t\t");
140 	  gen_exp (XVECEXP (x, 2, i), subroutine_type, used, info);
141 	}
142       printf (")");
143       return;
144 
145     case MATCH_PARALLEL:
146     case MATCH_PAR_DUP:
147       printf ("operand%d", XINT (x, 0));
148       return;
149 
150     case MATCH_SCRATCH:
151       gen_rtx_scratch (x, subroutine_type);
152       return;
153 
154     case PC:
155       printf ("pc_rtx");
156       return;
157     case RETURN:
158       printf ("ret_rtx");
159       return;
160     case SIMPLE_RETURN:
161       printf ("simple_return_rtx");
162       return;
163     case CLOBBER:
164       if (REG_P (XEXP (x, 0)))
165 	{
166 	  printf ("gen_hard_reg_clobber (%smode, %i)",
167 		  GET_MODE_NAME (GET_MODE (XEXP (x, 0))),
168 		  REGNO (XEXP (x, 0)));
169 	  return;
170 	}
171       break;
172 
173     case CONST_INT:
174       if (INTVAL (x) == 0)
175 	printf ("const0_rtx");
176       else if (INTVAL (x) == 1)
177 	printf ("const1_rtx");
178       else if (INTVAL (x) == -1)
179 	printf ("constm1_rtx");
180       else if (-MAX_SAVED_CONST_INT <= INTVAL (x)
181 	       && INTVAL (x) <= MAX_SAVED_CONST_INT)
182 	printf ("const_int_rtx[MAX_SAVED_CONST_INT + (%d)]",
183 		(int) INTVAL (x));
184       else if (INTVAL (x) == STORE_FLAG_VALUE)
185 	printf ("const_true_rtx");
186       else
187 	{
188 	  printf ("GEN_INT (");
189 	  printf ("HOST_WIDE_INT_C (");
190 	  printf (HOST_WIDE_INT_PRINT_DEC, INTVAL (x));
191 	  printf (")");
192 	  printf (")");
193 	}
194       return;
195 
196     case CONST_DOUBLE:
197       /* Handle `const_double_zero' rtx.  */
198       if (CONST_DOUBLE_REAL_VALUE (x)->cl == rvc_zero)
199 	{
200 	  printf ("CONST_DOUBLE_ATOF (\"0\", %smode)",
201 		  GET_MODE_NAME (GET_MODE (x)));
202 	  return;
203 	}
204       /* Fall through.  */
205     case CONST_FIXED:
206     case CONST_WIDE_INT:
207       /* These shouldn't be written in MD files.  Instead, the appropriate
208 	 routines in varasm.cc should be called.  */
209       gcc_unreachable ();
210 
211     default:
212       break;
213     }
214 
215   printf ("gen_rtx_");
216   print_code (code);
217   printf (" (");
218   if (!always_void_p (code))
219     {
220       printf ("%smode", GET_MODE_NAME (GET_MODE (x)));
221       sep = ",\n\t";
222     }
223 
224   fmt = GET_RTX_FORMAT (code);
225   len = GET_RTX_LENGTH (code);
226   for (i = 0; i < len; i++)
227     {
228       if (fmt[i] == '0')
229 	break;
230       fputs (sep, stdout);
231       switch (fmt[i])
232 	{
233 	case 'e': case 'u':
234 	  gen_exp (XEXP (x, i), subroutine_type, used, info);
235 	  break;
236 
237 	case 'i':
238 	  printf ("%u", XINT (x, i));
239 	  break;
240 
241 	case 'r':
242 	  printf ("%u", REGNO (x));
243 	  break;
244 
245 	case 'p':
246 	  /* We don't have a way of parsing polynomial offsets yet,
247 	     and hopefully never will.  */
248 	  printf ("%d", SUBREG_BYTE (x).to_constant ());
249 	  break;
250 
251 	case 's':
252 	  printf ("\"%s\"", XSTR (x, i));
253 	  break;
254 
255 	case 'E':
256 	  {
257 	    int j;
258 	    printf ("gen_rtvec (%d", XVECLEN (x, i));
259 	    for (j = 0; j < XVECLEN (x, i); j++)
260 	      {
261 		printf (",\n\t\t");
262 		gen_exp (XVECEXP (x, i, j), subroutine_type, used, info);
263 	      }
264 	    printf (")");
265 	    break;
266 	  }
267 
268 	default:
269 	  gcc_unreachable ();
270 	}
271       sep = ",\n\t";
272     }
273   printf (")");
274 }
275 
276 /* Output code to emit the instruction patterns in VEC, with each element
277    becoming a separate instruction.  USED is as for gen_exp.  */
278 
279 static void
gen_emit_seq(rtvec vec,char * used,md_rtx_info * info)280 gen_emit_seq (rtvec vec, char *used, md_rtx_info *info)
281 {
282   for (int i = 0, len = GET_NUM_ELEM (vec); i < len; ++i)
283     {
284       bool last_p = (i == len - 1);
285       rtx next = RTVEC_ELT (vec, i);
286       if (const char *name = get_emit_function (next))
287 	{
288 	  printf ("  %s (", name);
289 	  gen_exp (next, DEFINE_EXPAND, used, info);
290 	  printf (");\n");
291 	  if (!last_p && needs_barrier_p (next))
292 	    printf ("  emit_barrier ();");
293 	}
294       else
295 	{
296 	  printf ("  emit (");
297 	  gen_exp (next, DEFINE_EXPAND, used, info);
298 	  printf (", %s);\n", last_p ? "false" : "true");
299 	}
300     }
301 }
302 
303 /* Emit the given C code to the output file.  The code is allowed to
304    fail if CAN_FAIL_P.  NAME describes what we're generating,
305    for use in error messages.  */
306 
307 static void
emit_c_code(const char * code,bool can_fail_p,const char * name)308 emit_c_code (const char *code, bool can_fail_p, const char *name)
309 {
310   if (can_fail_p)
311     printf ("#define FAIL return (end_sequence (), _val)\n");
312   else
313     printf ("#define FAIL _Pragma (\"GCC error \\\"%s cannot FAIL\\\"\")"
314 	    " (void)0\n", name);
315   printf ("#define DONE return (_val = get_insns (), "
316 	  "end_sequence (), _val)\n");
317 
318   rtx_reader_ptr->print_md_ptr_loc (code);
319   printf ("%s\n", code);
320 
321   printf ("#undef DONE\n");
322   printf ("#undef FAIL\n");
323 }
324 
325 /* Generate the `gen_...' function for a DEFINE_INSN.  */
326 
327 static void
gen_insn(md_rtx_info * info)328 gen_insn (md_rtx_info *info)
329 {
330   struct pattern_stats stats;
331   int i;
332 
333   /* See if the pattern for this insn ends with a group of CLOBBERs of (hard)
334      registers or MATCH_SCRATCHes.  If so, store away the information for
335      later.  */
336 
337   rtx insn = info->def;
338   if (XVEC (insn, 1))
339     {
340       int has_hard_reg = 0;
341 
342       for (i = XVECLEN (insn, 1) - 1; i > 0; i--)
343 	{
344 	  if (GET_CODE (XVECEXP (insn, 1, i)) != CLOBBER)
345 	    break;
346 
347 	  if (REG_P (XEXP (XVECEXP (insn, 1, i), 0)))
348 	    has_hard_reg = 1;
349 	  else if (GET_CODE (XEXP (XVECEXP (insn, 1, i), 0)) != MATCH_SCRATCH)
350 	    break;
351 	}
352 
353       if (i != XVECLEN (insn, 1) - 1)
354 	{
355 	  struct clobber_pat *p;
356 	  struct clobber_ent *link = XNEW (struct clobber_ent);
357 	  int j;
358 
359 	  link->code_number = info->index;
360 
361 	  /* See if any previous CLOBBER_LIST entry is the same as this
362 	     one.  */
363 
364 	  for (p = clobber_list; p; p = p->next)
365 	    {
366 	      if (p->first_clobber != i + 1
367 		  || XVECLEN (p->pattern, 1) != XVECLEN (insn, 1))
368 		continue;
369 
370 	      for (j = i + 1; j < XVECLEN (insn, 1); j++)
371 		{
372 		  rtx old_rtx = XEXP (XVECEXP (p->pattern, 1, j), 0);
373 		  rtx new_rtx = XEXP (XVECEXP (insn, 1, j), 0);
374 
375 		  /* OLD and NEW_INSN are the same if both are to be a SCRATCH
376 		     of the same mode,
377 		     or if both are registers of the same mode and number.  */
378 		  if (! (GET_CODE (old_rtx) == GET_CODE (new_rtx)
379 			 && GET_MODE (old_rtx) == GET_MODE (new_rtx)
380 			 && ((GET_CODE (old_rtx) == MATCH_SCRATCH
381 			      && GET_CODE (new_rtx) == MATCH_SCRATCH)
382 			     || (REG_P (old_rtx) && REG_P (new_rtx)
383 				 && REGNO (old_rtx) == REGNO (new_rtx)))))
384 		    break;
385 		}
386 
387 	      if (j == XVECLEN (insn, 1))
388 		break;
389 	    }
390 
391 	  if (p == 0)
392 	    {
393 	      p = XNEW (struct clobber_pat);
394 
395 	      p->insns = 0;
396 	      p->pattern = insn;
397 	      p->first_clobber = i + 1;
398 	      p->next = clobber_list;
399 	      p->has_hard_reg = has_hard_reg;
400 	      clobber_list = p;
401 	    }
402 
403 	  link->next = p->insns;
404 	  p->insns = link;
405 	}
406     }
407 
408   /* Don't mention instructions whose names are the null string
409      or begin with '*'.  They are in the machine description just
410      to be recognized.  */
411   if (XSTR (insn, 0)[0] == 0 || XSTR (insn, 0)[0] == '*')
412     return;
413 
414   printf ("/* %s:%d */\n", info->loc.filename, info->loc.lineno);
415 
416   /* Find out how many operands this function has.  */
417   get_pattern_stats (&stats, XVEC (insn, 1));
418   if (stats.max_dup_opno > stats.max_opno)
419     fatal_at (info->loc, "match_dup operand number has no match_operand");
420 
421   /* Output the function name and argument declarations.  */
422   printf ("rtx\ngen_%s (", XSTR (insn, 0));
423   if (stats.num_generator_args)
424     for (i = 0; i < stats.num_generator_args; i++)
425       if (i)
426 	printf (",\n\trtx operand%d ATTRIBUTE_UNUSED", i);
427       else
428 	printf ("rtx operand%d ATTRIBUTE_UNUSED", i);
429   else
430     printf ("void");
431   printf (")\n");
432   printf ("{\n");
433 
434   /* Output code to construct and return the rtl for the instruction body.  */
435 
436   rtx pattern = add_implicit_parallel (XVEC (insn, 1));
437   /* ??? This is the traditional behavior, but seems suspect.  */
438   char *used = (XVECLEN (insn, 1) == 1
439 		? NULL
440 		: XCNEWVEC (char, stats.num_generator_args));
441   printf ("  return ");
442   gen_exp (pattern, DEFINE_INSN, used, info);
443   printf (";\n}\n\n");
444   XDELETEVEC (used);
445 }
446 
447 /* Generate the `gen_...' function for a DEFINE_EXPAND.  */
448 
449 static void
gen_expand(md_rtx_info * info)450 gen_expand (md_rtx_info *info)
451 {
452   struct pattern_stats stats;
453   int i;
454   char *used;
455 
456   rtx expand = info->def;
457   if (strlen (XSTR (expand, 0)) == 0)
458     fatal_at (info->loc, "define_expand lacks a name");
459   if (XVEC (expand, 1) == 0)
460     fatal_at (info->loc, "define_expand for %s lacks a pattern",
461 	      XSTR (expand, 0));
462 
463   /* Find out how many operands this function has.  */
464   get_pattern_stats (&stats, XVEC (expand, 1));
465   if (stats.min_scratch_opno != -1
466       && stats.min_scratch_opno <= MAX (stats.max_opno, stats.max_dup_opno))
467     fatal_at (info->loc, "define_expand for %s needs to have match_scratch "
468 			 "numbers above all other operands", XSTR (expand, 0));
469 
470   /* Output the function name and argument declarations.  */
471   printf ("rtx\ngen_%s (", XSTR (expand, 0));
472   if (stats.num_generator_args)
473     for (i = 0; i < stats.num_generator_args; i++)
474       if (i)
475 	printf (",\n\trtx operand%d", i);
476       else
477 	printf ("rtx operand%d", i);
478   else
479     printf ("void");
480   printf (")\n");
481   printf ("{\n");
482 
483   /* If we don't have any C code to write, only one insn is being written,
484      and no MATCH_DUPs are present, we can just return the desired insn
485      like we do for a DEFINE_INSN.  This saves memory.  */
486   if ((XSTR (expand, 3) == 0 || *XSTR (expand, 3) == '\0')
487       && stats.max_opno >= stats.max_dup_opno
488       && XVECLEN (expand, 1) == 1)
489     {
490       printf ("  return ");
491       gen_exp (XVECEXP (expand, 1, 0), DEFINE_EXPAND, NULL, info);
492       printf (";\n}\n\n");
493       return;
494     }
495 
496   /* For each operand referred to only with MATCH_DUPs,
497      make a local variable.  */
498   for (i = stats.num_generator_args; i <= stats.max_dup_opno; i++)
499     printf ("  rtx operand%d;\n", i);
500   printf ("  rtx_insn *_val = 0;\n");
501   printf ("  start_sequence ();\n");
502 
503   /* The fourth operand of DEFINE_EXPAND is some code to be executed
504      before the actual construction.
505      This code expects to refer to `operands'
506      just as the output-code in a DEFINE_INSN does,
507      but here `operands' is an automatic array.
508      So copy the operand values there before executing it.  */
509   if (XSTR (expand, 3) && *XSTR (expand, 3))
510     {
511       printf ("  {\n");
512       if (stats.num_operand_vars > 0)
513 	printf ("    rtx operands[%d];\n", stats.num_operand_vars);
514 
515       /* Output code to copy the arguments into `operands'.  */
516       for (i = 0; i < stats.num_generator_args; i++)
517 	printf ("    operands[%d] = operand%d;\n", i, i);
518 
519       /* Output the special code to be executed before the sequence
520 	 is generated.  */
521       optab_pattern p;
522       bool can_fail_p = true;
523       if (find_optab (&p, XSTR (expand, 0)))
524 	{
525 	  gcc_assert (p.op < NUM_OPTABS);
526 	  if (nofail_optabs[p.op])
527 	    can_fail_p = false;
528 	}
529       emit_c_code (XSTR (expand, 3), can_fail_p, XSTR (expand, 0));
530 
531       /* Output code to copy the arguments back out of `operands'
532 	 (unless we aren't going to use them at all).  */
533       if (XVEC (expand, 1) != 0)
534 	{
535 	  for (i = 0; i <= MAX (stats.max_opno, stats.max_dup_opno); i++)
536 	    {
537 	      printf ("    operand%d = operands[%d];\n", i, i);
538 	      printf ("    (void) operand%d;\n", i);
539 	    }
540 	}
541       printf ("  }\n");
542     }
543 
544   used = XCNEWVEC (char, stats.num_operand_vars);
545   gen_emit_seq (XVEC (expand, 1), used, info);
546   XDELETEVEC (used);
547 
548   /* Call `get_insns' to extract the list of all the
549      insns emitted within this gen_... function.  */
550 
551   printf ("  _val = get_insns ();\n");
552   printf ("  end_sequence ();\n");
553   printf ("  return _val;\n}\n\n");
554 }
555 
556 /* Like gen_expand, but generates insns resulting from splitting SPLIT.  */
557 
558 static void
gen_split(md_rtx_info * info)559 gen_split (md_rtx_info *info)
560 {
561   struct pattern_stats stats;
562   int i;
563   rtx split = info->def;
564   const char *const name =
565     ((GET_CODE (split) == DEFINE_PEEPHOLE2) ? "peephole2" : "split");
566   const char *unused;
567   char *used;
568 
569   if (XVEC (split, 0) == 0)
570     fatal_at (info->loc, "%s lacks a pattern",
571 	      GET_RTX_NAME (GET_CODE (split)));
572   else if (XVEC (split, 2) == 0)
573     fatal_at (info->loc, "%s lacks a replacement pattern",
574 	      GET_RTX_NAME (GET_CODE (split)));
575 
576   /* Find out how many operands this function has.  */
577 
578   get_pattern_stats (&stats, XVEC (split, 2));
579   unused = (stats.num_operand_vars == 0 ? " ATTRIBUTE_UNUSED" : "");
580   used = XCNEWVEC (char, stats.num_operand_vars);
581 
582   /* Output the prototype, function name and argument declarations.  */
583   if (GET_CODE (split) == DEFINE_PEEPHOLE2)
584     {
585       printf ("extern rtx_insn *gen_%s_%d (rtx_insn *, rtx *);\n",
586 	      name, info->index);
587       printf ("rtx_insn *\ngen_%s_%d (rtx_insn *curr_insn ATTRIBUTE_UNUSED,"
588 	      " rtx *operands%s)\n",
589 	      name, info->index, unused);
590     }
591   else
592     {
593       printf ("extern rtx_insn *gen_split_%d (rtx_insn *, rtx *);\n",
594 	      info->index);
595       printf ("rtx_insn *\ngen_split_%d "
596 	      "(rtx_insn *curr_insn ATTRIBUTE_UNUSED, rtx *operands%s)\n",
597 	      info->index, unused);
598     }
599   printf ("{\n");
600 
601   /* Declare all local variables.  */
602   for (i = 0; i < stats.num_operand_vars; i++)
603     printf ("  rtx operand%d;\n", i);
604   printf ("  rtx_insn *_val = NULL;\n");
605 
606   if (GET_CODE (split) == DEFINE_PEEPHOLE2)
607     output_peephole2_scratches (split);
608 
609   const char *fn = info->loc.filename;
610   for (const char *p = fn; *p; p++)
611     if (*p == '/')
612       fn = p + 1;
613 
614   printf ("  if (dump_file)\n");
615   printf ("    fprintf (dump_file, \"Splitting with gen_%s_%d (%s:%d)\\n\");\n",
616 	  name, info->index, fn, info->loc.lineno);
617 
618   printf ("  start_sequence ();\n");
619 
620   /* The fourth operand of DEFINE_SPLIT is some code to be executed
621      before the actual construction.  */
622 
623   if (XSTR (split, 3))
624     emit_c_code (XSTR (split, 3), true, name);
625 
626   /* Output code to copy the arguments back out of `operands'  */
627   for (i = 0; i < stats.num_operand_vars; i++)
628     {
629       printf ("  operand%d = operands[%d];\n", i, i);
630       printf ("  (void) operand%d;\n", i);
631     }
632 
633   gen_emit_seq (XVEC (split, 2), used, info);
634 
635   /* Call `get_insns' to make a list of all the
636      insns emitted within this gen_... function.  */
637 
638   printf ("  _val = get_insns ();\n");
639   printf ("  end_sequence ();\n");
640   printf ("  return _val;\n}\n\n");
641 
642   free (used);
643 }
644 
645 /* Write a function, `add_clobbers', that is given a PARALLEL of sufficient
646    size for the insn and an INSN_CODE, and inserts the required CLOBBERs at
647    the end of the vector.  */
648 
649 static void
output_add_clobbers(md_rtx_info * info)650 output_add_clobbers (md_rtx_info *info)
651 {
652   struct clobber_pat *clobber;
653   struct clobber_ent *ent;
654   int i;
655 
656   printf ("\n\nvoid\nadd_clobbers (rtx pattern ATTRIBUTE_UNUSED, int insn_code_number)\n");
657   printf ("{\n");
658   printf ("  switch (insn_code_number)\n");
659   printf ("    {\n");
660 
661   for (clobber = clobber_list; clobber; clobber = clobber->next)
662     {
663       for (ent = clobber->insns; ent; ent = ent->next)
664 	printf ("    case %d:\n", ent->code_number);
665 
666       for (i = clobber->first_clobber; i < XVECLEN (clobber->pattern, 1); i++)
667 	{
668 	  printf ("      XVECEXP (pattern, 0, %d) = ", i);
669 	  gen_exp (XVECEXP (clobber->pattern, 1, i),
670 		   GET_CODE (clobber->pattern), NULL, info);
671 	  printf (";\n");
672 	}
673 
674       printf ("      break;\n\n");
675     }
676 
677   printf ("    default:\n");
678   printf ("      gcc_unreachable ();\n");
679   printf ("    }\n");
680   printf ("}\n");
681 }
682 
683 /* Write a function, `added_clobbers_hard_reg_p' that is given an insn_code
684    number that will have clobbers added (as indicated by `recog') and returns
685    1 if those include a clobber of a hard reg or 0 if all of them just clobber
686    SCRATCH.  */
687 
688 static void
output_added_clobbers_hard_reg_p(void)689 output_added_clobbers_hard_reg_p (void)
690 {
691   struct clobber_pat *clobber;
692   struct clobber_ent *ent;
693   int clobber_p, used;
694 
695   printf ("\n\nint\nadded_clobbers_hard_reg_p (int insn_code_number)\n");
696   printf ("{\n");
697   printf ("  switch (insn_code_number)\n");
698   printf ("    {\n");
699 
700   for (clobber_p = 0; clobber_p <= 1; clobber_p++)
701     {
702       used = 0;
703       for (clobber = clobber_list; clobber; clobber = clobber->next)
704 	if (clobber->has_hard_reg == clobber_p)
705 	  for (ent = clobber->insns; ent; ent = ent->next)
706 	    {
707 	      printf ("    case %d:\n", ent->code_number);
708 	      used++;
709 	    }
710 
711       if (used)
712 	printf ("      return %d;\n\n", clobber_p);
713     }
714 
715   printf ("    default:\n");
716   printf ("      gcc_unreachable ();\n");
717   printf ("    }\n");
718   printf ("}\n");
719 }
720 
721 /* Generate code to invoke find_free_register () as needed for the
722    scratch registers used by the peephole2 pattern in SPLIT.  */
723 
724 static void
output_peephole2_scratches(rtx split)725 output_peephole2_scratches (rtx split)
726 {
727   int i;
728   int insn_nr = 0;
729   bool first = true;
730 
731   for (i = 0; i < XVECLEN (split, 0); i++)
732     {
733       rtx elt = XVECEXP (split, 0, i);
734       if (GET_CODE (elt) == MATCH_SCRATCH)
735 	{
736 	  int last_insn_nr = insn_nr;
737 	  int cur_insn_nr = insn_nr;
738 	  int j;
739 	  for (j = i + 1; j < XVECLEN (split, 0); j++)
740 	    if (GET_CODE (XVECEXP (split, 0, j)) == MATCH_DUP)
741 	      {
742 		if (XINT (XVECEXP (split, 0, j), 0) == XINT (elt, 0))
743 		  last_insn_nr = cur_insn_nr;
744 	      }
745 	    else if (GET_CODE (XVECEXP (split, 0, j)) != MATCH_SCRATCH)
746 	      cur_insn_nr++;
747 
748 	  if (first)
749 	    {
750 	      printf ("  HARD_REG_SET _regs_allocated;\n");
751 	      printf ("  CLEAR_HARD_REG_SET (_regs_allocated);\n");
752 	      first = false;
753 	    }
754 
755 	  printf ("  if ((operands[%d] = peep2_find_free_register (%d, %d, \"%s\", %smode, &_regs_allocated)) == NULL_RTX)\n\
756     return NULL;\n",
757 		  XINT (elt, 0),
758 		  insn_nr, last_insn_nr,
759 		  XSTR (elt, 1),
760 		  GET_MODE_NAME (GET_MODE (elt)));
761 
762 	}
763       else if (GET_CODE (elt) != MATCH_DUP)
764 	insn_nr++;
765     }
766 }
767 
768 /* Print "arg<N>" parameter declarations for each argument N of ONAME.  */
769 
770 static void
print_overload_arguments(overloaded_name * oname)771 print_overload_arguments (overloaded_name *oname)
772 {
773   for (unsigned int i = 0; i < oname->arg_types.length (); ++i)
774     printf ("%s%s arg%d", i == 0 ? "" : ", ", oname->arg_types[i], i);
775 }
776 
777 /* Print code to test whether INSTANCE should be chosen, given that
778    argument N of the overload is available as "arg<N>".  */
779 
780 static void
print_overload_test(overloaded_instance * instance)781 print_overload_test (overloaded_instance *instance)
782 {
783   for (unsigned int i = 0; i < instance->arg_values.length (); ++i)
784     printf ("%sarg%d == %s", i == 0 ? "  if (" : "\n      && ",
785 	    i, instance->arg_values[i]);
786   printf (")\n");
787 }
788 
789 /* Emit a maybe_code_for_* function for ONAME.  */
790 
791 static void
handle_overloaded_code_for(overloaded_name * oname)792 handle_overloaded_code_for (overloaded_name *oname)
793 {
794   /* Print the function prototype.  */
795   printf ("\ninsn_code\nmaybe_code_for_%s (", oname->name);
796   print_overload_arguments (oname);
797   printf (")\n{\n");
798 
799   /* Use a sequence of "if" statements for each instance.  */
800   for (overloaded_instance *instance = oname->first_instance;
801        instance; instance = instance->next)
802     {
803       print_overload_test (instance);
804       printf ("    return CODE_FOR_%s;\n", instance->name);
805     }
806 
807   /* Return null if no match was found.  */
808   printf ("  return CODE_FOR_nothing;\n}\n");
809 }
810 
811 /* Emit a maybe_gen_* function for ONAME.  */
812 
813 static void
handle_overloaded_gen(overloaded_name * oname)814 handle_overloaded_gen (overloaded_name *oname)
815 {
816   unsigned HOST_WIDE_INT seen = 0;
817   /* All patterns must have the same number of operands.  */
818   for (overloaded_instance *instance = oname->first_instance->next;
819        instance; instance = instance->next)
820     {
821       pattern_stats stats;
822       get_pattern_stats (&stats, XVEC (instance->insn, 1));
823       unsigned HOST_WIDE_INT mask
824 	= HOST_WIDE_INT_1U << stats.num_generator_args;
825       if (seen & mask)
826 	continue;
827 
828       seen |= mask;
829 
830       /* Print the function prototype.  */
831       printf ("\nrtx\nmaybe_gen_%s (", oname->name);
832       print_overload_arguments (oname);
833       for (int i = 0; i < stats.num_generator_args; ++i)
834 	printf (", rtx x%d", i);
835       printf (")\n{\n");
836 
837       /* Use maybe_code_for_*, instead of duplicating the selection
838 	 logic here.  */
839       printf ("  insn_code code = maybe_code_for_%s (", oname->name);
840       for (unsigned int i = 0; i < oname->arg_types.length (); ++i)
841 	printf ("%sarg%d", i == 0 ? "" : ", ", i);
842       printf (");\n"
843 	      "  if (code != CODE_FOR_nothing)\n"
844 	      "    {\n"
845 	      "      gcc_assert (insn_data[code].n_generator_args == %d);\n"
846 	      "      return GEN_FCN (code) (", stats.num_generator_args);
847       for (int i = 0; i < stats.num_generator_args; ++i)
848 	printf ("%sx%d", i == 0 ? "" : ", ", i);
849       printf (");\n"
850 	      "    }\n"
851 	      "  else\n"
852 	      "    return NULL_RTX;\n"
853 	      "}\n");
854     }
855 }
856 
857 int
main(int argc,const char ** argv)858 main (int argc, const char **argv)
859 {
860   progname = "genemit";
861 
862   if (!init_rtx_reader_args (argc, argv))
863     return (FATAL_EXIT_CODE);
864 
865 #define DEF_INTERNAL_OPTAB_FN(NAME, FLAGS, OPTAB, TYPE) \
866   nofail_optabs[OPTAB##_optab] = true;
867 #include "internal-fn.def"
868 
869   /* Assign sequential codes to all entries in the machine description
870      in parallel with the tables in insn-output.cc.  */
871 
872   printf ("/* Generated automatically by the program `genemit'\n\
873 from the machine description file `md'.  */\n\n");
874 
875   printf ("#define IN_TARGET_CODE 1\n");
876   printf ("#include \"config.h\"\n");
877   printf ("#include \"system.h\"\n");
878   printf ("#include \"coretypes.h\"\n");
879   printf ("#include \"backend.h\"\n");
880   printf ("#include \"predict.h\"\n");
881   printf ("#include \"tree.h\"\n");
882   printf ("#include \"rtl.h\"\n");
883   printf ("#include \"alias.h\"\n");
884   printf ("#include \"varasm.h\"\n");
885   printf ("#include \"stor-layout.h\"\n");
886   printf ("#include \"calls.h\"\n");
887   printf ("#include \"memmodel.h\"\n");
888   printf ("#include \"tm_p.h\"\n");
889   printf ("#include \"flags.h\"\n");
890   printf ("#include \"insn-config.h\"\n");
891   printf ("#include \"expmed.h\"\n");
892   printf ("#include \"dojump.h\"\n");
893   printf ("#include \"explow.h\"\n");
894   printf ("#include \"emit-rtl.h\"\n");
895   printf ("#include \"stmt.h\"\n");
896   printf ("#include \"expr.h\"\n");
897   printf ("#include \"insn-codes.h\"\n");
898   printf ("#include \"optabs.h\"\n");
899   printf ("#include \"dfp.h\"\n");
900   printf ("#include \"output.h\"\n");
901   printf ("#include \"recog.h\"\n");
902   printf ("#include \"df.h\"\n");
903   printf ("#include \"resource.h\"\n");
904   printf ("#include \"reload.h\"\n");
905   printf ("#include \"diagnostic-core.h\"\n");
906   printf ("#include \"regs.h\"\n");
907   printf ("#include \"tm-constrs.h\"\n");
908   printf ("#include \"ggc.h\"\n");
909   printf ("#include \"target.h\"\n\n");
910 
911   /* Read the machine description.  */
912 
913   md_rtx_info info;
914   while (read_md_rtx (&info))
915     switch (GET_CODE (info.def))
916       {
917       case DEFINE_INSN:
918 	gen_insn (&info);
919 	break;
920 
921       case DEFINE_EXPAND:
922 	printf ("/* %s:%d */\n", info.loc.filename, info.loc.lineno);
923 	gen_expand (&info);
924 	break;
925 
926       case DEFINE_SPLIT:
927 	printf ("/* %s:%d */\n", info.loc.filename, info.loc.lineno);
928 	gen_split (&info);
929 	break;
930 
931       case DEFINE_PEEPHOLE2:
932 	printf ("/* %s:%d */\n", info.loc.filename, info.loc.lineno);
933 	gen_split (&info);
934 	break;
935 
936       default:
937 	break;
938       }
939 
940   /* Write out the routines to add CLOBBERs to a pattern and say whether they
941      clobber a hard reg.  */
942   output_add_clobbers (&info);
943   output_added_clobbers_hard_reg_p ();
944 
945   for (overloaded_name *oname = rtx_reader_ptr->get_overloads ();
946        oname; oname = oname->next)
947     {
948       handle_overloaded_code_for (oname);
949       handle_overloaded_gen (oname);
950     }
951 
952   fflush (stdout);
953   return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
954 }
955