1 /* Generate from machine description:
2    - prototype declarations for operand predicates (tm-preds.h)
3    - function definitions of operand predicates, if defined new-style
4      (insn-preds.c)
5    Copyright (C) 2001-2016 Free Software Foundation, Inc.
6 
7 This file is part of GCC.
8 
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
12 any later version.
13 
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 GNU General Public License for more details.
18 
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3.  If not see
21 <http://www.gnu.org/licenses/>.  */
22 
23 #include "bconfig.h"
24 #include "system.h"
25 #include "coretypes.h"
26 #include "tm.h"
27 #include "rtl.h"
28 #include "errors.h"
29 #include "obstack.h"
30 #include "read-md.h"
31 #include "gensupport.h"
32 
33 static char general_mem[] = { TARGET_MEM_CONSTRAINT, 0 };
34 
35 /* Given a predicate expression EXP, from form NAME at location LOC,
36    verify that it does not contain any RTL constructs which are not
37    valid in predicate definitions.  Returns true if EXP is
38    INvalid; issues error messages, caller need not.  */
39 static bool
validate_exp(rtx exp,const char * name,file_location loc)40 validate_exp (rtx exp, const char *name, file_location loc)
41 {
42   if (exp == 0)
43     {
44       message_at (loc, "%s: must give a predicate expression", name);
45       return true;
46     }
47 
48   switch (GET_CODE (exp))
49     {
50       /* Ternary, binary, unary expressions: recurse into subexpressions.  */
51     case IF_THEN_ELSE:
52       if (validate_exp (XEXP (exp, 2), name, loc))
53 	return true;
54       /* else fall through */
55     case AND:
56     case IOR:
57       if (validate_exp (XEXP (exp, 1), name, loc))
58 	return true;
59       /* else fall through */
60     case NOT:
61       return validate_exp (XEXP (exp, 0), name, loc);
62 
63       /* MATCH_CODE might have a syntax error in its path expression.  */
64     case MATCH_CODE:
65       {
66 	const char *p;
67 	for (p = XSTR (exp, 1); *p; p++)
68 	  {
69 	    if (!ISDIGIT (*p) && !ISLOWER (*p))
70 	      {
71 		error_at (loc, "%s: invalid character in path "
72 			  "string '%s'", name, XSTR (exp, 1));
73 		return true;
74 	      }
75 	  }
76       }
77       /* fall through */
78 
79       /* These need no special checking.  */
80     case MATCH_OPERAND:
81     case MATCH_TEST:
82       return false;
83 
84     default:
85       error_at (loc, "%s: cannot use '%s' in a predicate expression",
86 		name, GET_RTX_NAME (GET_CODE (exp)));
87       return true;
88     }
89 }
90 
91 /* Predicates are defined with (define_predicate) or
92    (define_special_predicate) expressions in the machine description.  */
93 static void
process_define_predicate(md_rtx_info * info)94 process_define_predicate (md_rtx_info *info)
95 {
96   validate_exp (XEXP (info->def, 1), XSTR (info->def, 0), info->loc);
97 }
98 
99 /* Given a predicate, if it has an embedded C block, write the block
100    out as a static inline subroutine, and augment the RTL test with a
101    match_test that calls that subroutine.  For instance,
102 
103        (define_predicate "basereg_operand"
104          (match_operand 0 "register_operand")
105        {
106          if (GET_CODE (op) == SUBREG)
107            op = SUBREG_REG (op);
108          return REG_POINTER (op);
109        })
110 
111    becomes
112 
113        static inline int basereg_operand_1(rtx op, machine_mode mode)
114        {
115          if (GET_CODE (op) == SUBREG)
116            op = SUBREG_REG (op);
117          return REG_POINTER (op);
118        }
119 
120        (define_predicate "basereg_operand"
121          (and (match_operand 0 "register_operand")
122 	      (match_test "basereg_operand_1 (op, mode)")))
123 
124    The only wart is that there's no way to insist on a { } string in
125    an RTL template, so we have to handle "" strings.  */
126 
127 
128 static void
write_predicate_subfunction(struct pred_data * p)129 write_predicate_subfunction (struct pred_data *p)
130 {
131   const char *match_test_str;
132   rtx match_test_exp, and_exp;
133 
134   if (p->c_block[0] == '\0')
135     return;
136 
137   /* Construct the function-call expression.  */
138   obstack_grow (rtl_obstack, p->name, strlen (p->name));
139   obstack_grow (rtl_obstack, "_1 (op, mode)",
140 		sizeof "_1 (op, mode)");
141   match_test_str = XOBFINISH (rtl_obstack, const char *);
142 
143   /* Add the function-call expression to the complete expression to be
144      evaluated.  */
145   match_test_exp = rtx_alloc (MATCH_TEST);
146   XSTR (match_test_exp, 0) = match_test_str;
147 
148   and_exp = rtx_alloc (AND);
149   XEXP (and_exp, 0) = p->exp;
150   XEXP (and_exp, 1) = match_test_exp;
151 
152   p->exp = and_exp;
153 
154   printf ("static inline int\n"
155 	  "%s_1 (rtx op, machine_mode mode ATTRIBUTE_UNUSED)\n",
156 	  p->name);
157   print_md_ptr_loc (p->c_block);
158   if (p->c_block[0] == '{')
159     fputs (p->c_block, stdout);
160   else
161     printf ("{\n  %s\n}", p->c_block);
162   fputs ("\n\n", stdout);
163 }
164 
165 /* Given a predicate expression EXP, from form NAME, determine whether
166    it refers to the variable given as VAR.  */
167 static bool
needs_variable(rtx exp,const char * var)168 needs_variable (rtx exp, const char *var)
169 {
170   switch (GET_CODE (exp))
171     {
172       /* Ternary, binary, unary expressions need a variable if
173 	 any of their subexpressions do.  */
174     case IF_THEN_ELSE:
175       if (needs_variable (XEXP (exp, 2), var))
176 	return true;
177       /* else fall through */
178     case AND:
179     case IOR:
180       if (needs_variable (XEXP (exp, 1), var))
181 	return true;
182       /* else fall through */
183     case NOT:
184       return needs_variable (XEXP (exp, 0), var);
185 
186       /* MATCH_CODE uses "op", but nothing else.  */
187     case MATCH_CODE:
188       return !strcmp (var, "op");
189 
190       /* MATCH_OPERAND uses "op" and may use "mode".  */
191     case MATCH_OPERAND:
192       if (!strcmp (var, "op"))
193 	return true;
194       if (!strcmp (var, "mode") && GET_MODE (exp) == VOIDmode)
195 	return true;
196       return false;
197 
198       /* MATCH_TEST uses var if XSTR (exp, 0) =~ /\b${var}\b/o; */
199     case MATCH_TEST:
200       {
201 	const char *p = XSTR (exp, 0);
202 	const char *q = strstr (p, var);
203 	if (!q)
204 	  return false;
205 	if (q != p && (ISALNUM (q[-1]) || q[-1] == '_'))
206 	  return false;
207 	q += strlen (var);
208 	if (ISALNUM (q[0]) || q[0] == '_')
209 	  return false;
210       }
211       return true;
212 
213     default:
214       gcc_unreachable ();
215     }
216 }
217 
218 /* Given an RTL expression EXP, find all subexpressions which we may
219    assume to perform mode tests.  Normal MATCH_OPERAND does;
220    MATCH_CODE doesn't as such (although certain codes always have
221    VOIDmode); and we have to assume that MATCH_TEST does not.
222    These combine in almost-boolean fashion - the only exception is
223    that (not X) must be assumed not to perform a mode test, whether
224    or not X does.
225 
226    The mark is the RTL /v flag, which is true for subexpressions which
227    do *not* perform mode tests.
228 */
229 #define NO_MODE_TEST(EXP) RTX_FLAG (EXP, volatil)
230 static void
mark_mode_tests(rtx exp)231 mark_mode_tests (rtx exp)
232 {
233   switch (GET_CODE (exp))
234     {
235     case MATCH_OPERAND:
236       {
237 	struct pred_data *p = lookup_predicate (XSTR (exp, 1));
238 	if (!p)
239 	  error ("reference to undefined predicate '%s'", XSTR (exp, 1));
240 	else if (p->special || GET_MODE (exp) != VOIDmode)
241 	  NO_MODE_TEST (exp) = 1;
242       }
243       break;
244 
245     case MATCH_CODE:
246       NO_MODE_TEST (exp) = 1;
247       break;
248 
249     case MATCH_TEST:
250     case NOT:
251       NO_MODE_TEST (exp) = 1;
252       break;
253 
254     case AND:
255       mark_mode_tests (XEXP (exp, 0));
256       mark_mode_tests (XEXP (exp, 1));
257 
258       NO_MODE_TEST (exp) = (NO_MODE_TEST (XEXP (exp, 0))
259 			    && NO_MODE_TEST (XEXP (exp, 1)));
260       break;
261 
262     case IOR:
263       mark_mode_tests (XEXP (exp, 0));
264       mark_mode_tests (XEXP (exp, 1));
265 
266       NO_MODE_TEST (exp) = (NO_MODE_TEST (XEXP (exp, 0))
267 			    || NO_MODE_TEST (XEXP (exp, 1)));
268       break;
269 
270     case IF_THEN_ELSE:
271       /* A ? B : C does a mode test if (one of A and B) does a mode
272 	 test, and C does too.  */
273       mark_mode_tests (XEXP (exp, 0));
274       mark_mode_tests (XEXP (exp, 1));
275       mark_mode_tests (XEXP (exp, 2));
276 
277       NO_MODE_TEST (exp) = ((NO_MODE_TEST (XEXP (exp, 0))
278 			     && NO_MODE_TEST (XEXP (exp, 1)))
279 			    || NO_MODE_TEST (XEXP (exp, 2)));
280       break;
281 
282     default:
283       gcc_unreachable ();
284     }
285 }
286 
287 /* Determine whether the expression EXP is a MATCH_CODE that should
288    be written as a switch statement.  */
289 static bool
generate_switch_p(rtx exp)290 generate_switch_p (rtx exp)
291 {
292   return GET_CODE (exp) == MATCH_CODE
293 	 && strchr (XSTR (exp, 0), ',');
294 }
295 
296 /* Given a predicate, work out where in its RTL expression to add
297    tests for proper modes.  Special predicates do not get any such
298    tests.  We try to avoid adding tests when we don't have to; in
299    particular, other normal predicates can be counted on to do it for
300    us.  */
301 
302 static void
add_mode_tests(struct pred_data * p)303 add_mode_tests (struct pred_data *p)
304 {
305   rtx match_test_exp, and_exp;
306   rtx *pos;
307 
308   /* Don't touch special predicates.  */
309   if (p->special)
310     return;
311 
312   /* Check whether the predicate accepts const scalar ints (which always
313      have a stored mode of VOIDmode, but logically have a real mode)
314      and whether it matches anything besides const scalar ints.  */
315   bool matches_const_scalar_int_p = false;
316   bool matches_other_p = false;
317   for (int i = 0; i < NUM_RTX_CODE; ++i)
318     if (p->codes[i])
319       switch (i)
320 	{
321 	case CONST_INT:
322 	case CONST_WIDE_INT:
323 	  /* Special handling for (VOIDmode) LABEL_REFs.  */
324 	case LABEL_REF:
325 	  matches_const_scalar_int_p = true;
326 	  break;
327 
328 	case CONST_DOUBLE:
329 	  if (!TARGET_SUPPORTS_WIDE_INT)
330 	    matches_const_scalar_int_p = true;
331 	  matches_other_p = true;
332 	  break;
333 
334 	default:
335 	  matches_other_p = true;
336 	  break;
337 	}
338 
339   /* There's no need for a mode check if the predicate only accepts
340      constant integers.  The code checks in the predicate are enough
341      to establish that the mode is VOIDmode.
342 
343      Note that the predicate itself should check whether a scalar
344      integer is in range of the given mode.  */
345   if (!matches_other_p)
346     return;
347 
348   mark_mode_tests (p->exp);
349 
350   /* If the whole expression already tests the mode, we're done.  */
351   if (!NO_MODE_TEST (p->exp))
352     return;
353 
354   match_test_exp = rtx_alloc (MATCH_TEST);
355   if (matches_const_scalar_int_p)
356     XSTR (match_test_exp, 0) = ("mode == VOIDmode || GET_MODE (op) == mode"
357 				" || GET_MODE (op) == VOIDmode");
358   else
359     XSTR (match_test_exp, 0) = "mode == VOIDmode || GET_MODE (op) == mode";
360   and_exp = rtx_alloc (AND);
361   XEXP (and_exp, 1) = match_test_exp;
362 
363   /* It is always correct to rewrite p->exp as
364 
365         (and (...) (match_test "mode == VOIDmode || GET_MODE (op) == mode"))
366 
367      but there are a couple forms where we can do better.  If the
368      top-level pattern is an IOR, and one of the two branches does test
369      the mode, we can wrap just the branch that doesn't.  Likewise, if
370      we have an IF_THEN_ELSE, and one side of it tests the mode, we can
371      wrap just the side that doesn't.  And, of course, we can repeat this
372      descent as many times as it works.  */
373 
374   pos = &p->exp;
375   for (;;)
376     {
377       rtx subexp = *pos;
378 
379       switch (GET_CODE (subexp))
380 	{
381 	case AND:
382 	  /* The switch code generation in write_predicate_stmts prefers
383 	     rtx code tests to be at the top of the expression tree.  So
384 	     push this AND down into the second operand of an existing
385 	     AND expression.  */
386 	  if (generate_switch_p (XEXP (subexp, 0)))
387 	    pos = &XEXP (subexp, 1);
388 	  goto break_loop;
389 
390 	case IOR:
391 	  {
392 	    int test0 = NO_MODE_TEST (XEXP (subexp, 0));
393 	    int test1 = NO_MODE_TEST (XEXP (subexp, 1));
394 
395 	    gcc_assert (test0 || test1);
396 
397 	    if (test0 && test1)
398 	      goto break_loop;
399 	    pos = test0 ? &XEXP (subexp, 0) : &XEXP (subexp, 1);
400 	  }
401 	  break;
402 
403 	case IF_THEN_ELSE:
404 	  {
405 	    int test0 = NO_MODE_TEST (XEXP (subexp, 0));
406 	    int test1 = NO_MODE_TEST (XEXP (subexp, 1));
407 	    int test2 = NO_MODE_TEST (XEXP (subexp, 2));
408 
409 	    gcc_assert ((test0 && test1) || test2);
410 
411 	    if (test0 && test1 && test2)
412 	      goto break_loop;
413 	    if (test0 && test1)
414 	      /* Must put it on the dependent clause, not the
415 	      	 controlling expression, or we change the meaning of
416 	      	 the test.  */
417 	      pos = &XEXP (subexp, 1);
418 	    else
419 	      pos = &XEXP (subexp, 2);
420 	  }
421 	  break;
422 
423 	default:
424 	  goto break_loop;
425 	}
426     }
427  break_loop:
428   XEXP (and_exp, 0) = *pos;
429   *pos = and_exp;
430 }
431 
432 /* PATH is a string describing a path from the root of an RTL
433    expression to an inner subexpression to be tested.  Output
434    code which computes the subexpression from the variable
435    holding the root of the expression.  */
436 static void
write_extract_subexp(const char * path)437 write_extract_subexp (const char *path)
438 {
439   int len = strlen (path);
440   int i;
441 
442   /* We first write out the operations (XEXP or XVECEXP) in reverse
443      order, then write "op", then the indices in forward order.  */
444   for (i = len - 1; i >= 0; i--)
445     {
446       if (ISLOWER (path[i]))
447 	fputs ("XVECEXP (", stdout);
448       else if (ISDIGIT (path[i]))
449 	fputs ("XEXP (", stdout);
450       else
451 	gcc_unreachable ();
452     }
453 
454   fputs ("op", stdout);
455 
456   for (i = 0; i < len; i++)
457     {
458       if (ISLOWER (path[i]))
459 	printf (", 0, %d)", path[i] - 'a');
460       else if (ISDIGIT (path[i]))
461 	printf (", %d)", path[i] - '0');
462       else
463 	gcc_unreachable ();
464     }
465 }
466 
467 /* CODES is a list of RTX codes.  Write out an expression which
468    determines whether the operand has one of those codes.  */
469 static void
write_match_code(const char * path,const char * codes)470 write_match_code (const char *path, const char *codes)
471 {
472   const char *code;
473 
474   while ((code = scan_comma_elt (&codes)) != 0)
475     {
476       fputs ("GET_CODE (", stdout);
477       write_extract_subexp (path);
478       fputs (") == ", stdout);
479       while (code < codes)
480 	{
481 	  putchar (TOUPPER (*code));
482 	  code++;
483 	}
484 
485       if (*codes == ',')
486 	fputs (" || ", stdout);
487     }
488 }
489 
490 /* EXP is an RTL (sub)expression for a predicate.  Recursively
491    descend the expression and write out an equivalent C expression.  */
492 static void
write_predicate_expr(rtx exp)493 write_predicate_expr (rtx exp)
494 {
495   switch (GET_CODE (exp))
496     {
497     case AND:
498       putchar ('(');
499       write_predicate_expr (XEXP (exp, 0));
500       fputs (") && (", stdout);
501       write_predicate_expr (XEXP (exp, 1));
502       putchar (')');
503       break;
504 
505     case IOR:
506       putchar ('(');
507       write_predicate_expr (XEXP (exp, 0));
508       fputs (") || (", stdout);
509       write_predicate_expr (XEXP (exp, 1));
510       putchar (')');
511       break;
512 
513     case NOT:
514       fputs ("!(", stdout);
515       write_predicate_expr (XEXP (exp, 0));
516       putchar (')');
517       break;
518 
519     case IF_THEN_ELSE:
520       putchar ('(');
521       write_predicate_expr (XEXP (exp, 0));
522       fputs (") ? (", stdout);
523       write_predicate_expr (XEXP (exp, 1));
524       fputs (") : (", stdout);
525       write_predicate_expr (XEXP (exp, 2));
526       putchar (')');
527       break;
528 
529     case MATCH_OPERAND:
530       if (GET_MODE (exp) == VOIDmode)
531         printf ("%s (op, mode)", XSTR (exp, 1));
532       else
533         printf ("%s (op, %smode)", XSTR (exp, 1), mode_name[GET_MODE (exp)]);
534       break;
535 
536     case MATCH_CODE:
537       write_match_code (XSTR (exp, 1), XSTR (exp, 0));
538       break;
539 
540     case MATCH_TEST:
541       print_c_condition (XSTR (exp, 0));
542       break;
543 
544     default:
545       gcc_unreachable ();
546     }
547 }
548 
549 /* Write the MATCH_CODE expression EXP as a switch statement.  */
550 
551 static void
write_match_code_switch(rtx exp)552 write_match_code_switch (rtx exp)
553 {
554   const char *codes = XSTR (exp, 0);
555   const char *path = XSTR (exp, 1);
556   const char *code;
557 
558   fputs ("  switch (GET_CODE (", stdout);
559   write_extract_subexp (path);
560   fputs ("))\n    {\n", stdout);
561 
562   while ((code = scan_comma_elt (&codes)) != 0)
563     {
564       fputs ("    case ", stdout);
565       while (code < codes)
566 	{
567 	  putchar (TOUPPER (*code));
568 	  code++;
569 	}
570       fputs (":\n", stdout);
571     }
572 }
573 
574 /* Given a predicate expression EXP, write out a sequence of stmts
575    to evaluate it.  This is similar to write_predicate_expr but can
576    generate efficient switch statements.  */
577 
578 static void
write_predicate_stmts(rtx exp)579 write_predicate_stmts (rtx exp)
580 {
581   switch (GET_CODE (exp))
582     {
583     case MATCH_CODE:
584       if (generate_switch_p (exp))
585 	{
586 	  write_match_code_switch (exp);
587 	  puts ("      return true;\n"
588 		"    default:\n"
589 		"      break;\n"
590 		"    }\n"
591 		"  return false;");
592 	  return;
593 	}
594       break;
595 
596     case AND:
597       if (generate_switch_p (XEXP (exp, 0)))
598 	{
599 	  write_match_code_switch (XEXP (exp, 0));
600 	  puts ("      break;\n"
601 		"    default:\n"
602 		"      return false;\n"
603 		"    }");
604 	  exp = XEXP (exp, 1);
605 	}
606       break;
607 
608     case IOR:
609       if (generate_switch_p (XEXP (exp, 0)))
610 	{
611 	  write_match_code_switch (XEXP (exp, 0));
612 	  puts ("      return true;\n"
613 		"    default:\n"
614 		"      break;\n"
615 		"    }");
616 	  exp = XEXP (exp, 1);
617 	}
618       break;
619 
620     case NOT:
621       if (generate_switch_p (XEXP (exp, 0)))
622 	{
623 	  write_match_code_switch (XEXP (exp, 0));
624 	  puts ("      return false;\n"
625 		"    default:\n"
626 		"      break;\n"
627 		"    }\n"
628 		"  return true;");
629 	  return;
630 	}
631       break;
632 
633     default:
634       break;
635     }
636 
637   fputs ("  return ",stdout);
638   write_predicate_expr (exp);
639   fputs (";\n", stdout);
640 }
641 
642 /* Given a predicate, write out a complete C function to compute it.  */
643 static void
write_one_predicate_function(struct pred_data * p)644 write_one_predicate_function (struct pred_data *p)
645 {
646   if (!p->exp)
647     return;
648 
649   write_predicate_subfunction (p);
650   add_mode_tests (p);
651 
652   /* A normal predicate can legitimately not look at machine_mode
653      if it accepts only CONST_INTs and/or CONST_WIDE_INT and/or CONST_DOUBLEs.  */
654   printf ("int\n%s (rtx op, machine_mode mode ATTRIBUTE_UNUSED)\n{\n",
655 	  p->name);
656   write_predicate_stmts (p->exp);
657   fputs ("}\n\n", stdout);
658 }
659 
660 /* Constraints fall into two categories: register constraints
661    (define_register_constraint), and others (define_constraint,
662    define_memory_constraint, define_special_memory_constraint,
663    define_address_constraint).  We work out automatically which of the
664    various old-style macros they correspond to, and produce
665    appropriate code.  They all go in the same hash table so we can
666    verify that there are no duplicate names.  */
667 
668 /* All data from one constraint definition.  */
669 struct constraint_data
670 {
671   struct constraint_data *next_this_letter;
672   struct constraint_data *next_textual;
673   const char *name;
674   const char *c_name;    /* same as .name unless mangling is necessary */
675   file_location loc;     /* location of definition */
676   size_t namelen;
677   const char *regclass;  /* for register constraints */
678   rtx exp;               /* for other constraints */
679   unsigned int is_register	: 1;
680   unsigned int is_const_int	: 1;
681   unsigned int is_const_dbl	: 1;
682   unsigned int is_extra		: 1;
683   unsigned int is_memory	: 1;
684   unsigned int is_special_memory: 1;
685   unsigned int is_address	: 1;
686   unsigned int maybe_allows_reg : 1;
687   unsigned int maybe_allows_mem : 1;
688 };
689 
690 /* Overview of all constraints beginning with a given letter.  */
691 
692 static struct constraint_data *
693 constraints_by_letter_table[1<<CHAR_BIT];
694 
695 /* For looking up all the constraints in the order that they appeared
696    in the machine description.  */
697 static struct constraint_data *first_constraint;
698 static struct constraint_data **last_constraint_ptr = &first_constraint;
699 
700 #define FOR_ALL_CONSTRAINTS(iter_) \
701   for (iter_ = first_constraint; iter_; iter_ = iter_->next_textual)
702 
703 /* Contraint letters that have a special meaning and that cannot be used
704    in define*_constraints.  */
705 static const char generic_constraint_letters[] = "g";
706 
707 /* Machine-independent code expects that constraints with these
708    (initial) letters will allow only (a subset of all) CONST_INTs.  */
709 
710 static const char const_int_constraints[] = "IJKLMNOP";
711 
712 /* Machine-independent code expects that constraints with these
713    (initial) letters will allow only (a subset of all) CONST_DOUBLEs.  */
714 
715 static const char const_dbl_constraints[] = "GH";
716 
717 /* Summary data used to decide whether to output various functions and
718    macro definitions.  */
719 static unsigned int constraint_max_namelen;
720 static bool have_register_constraints;
721 static bool have_memory_constraints;
722 static bool have_special_memory_constraints;
723 static bool have_address_constraints;
724 static bool have_extra_constraints;
725 static bool have_const_int_constraints;
726 static unsigned int num_constraints;
727 
728 static const constraint_data **enum_order;
729 static unsigned int register_start, register_end;
730 static unsigned int satisfied_start;
731 static unsigned int const_int_start, const_int_end;
732 static unsigned int memory_start, memory_end;
733 static unsigned int special_memory_start, special_memory_end;
734 static unsigned int address_start, address_end;
735 static unsigned int maybe_allows_none_start, maybe_allows_none_end;
736 static unsigned int maybe_allows_reg_start, maybe_allows_reg_end;
737 static unsigned int maybe_allows_mem_start, maybe_allows_mem_end;
738 
739 /* Convert NAME, which contains angle brackets and/or underscores, to
740    a string that can be used as part of a C identifier.  The string
741    comes from the rtl_obstack.  */
742 static const char *
mangle(const char * name)743 mangle (const char *name)
744 {
745   for (; *name; name++)
746     switch (*name)
747       {
748       case '_': obstack_grow (rtl_obstack, "__", 2); break;
749       case '<':	obstack_grow (rtl_obstack, "_l", 2); break;
750       case '>':	obstack_grow (rtl_obstack, "_g", 2); break;
751       default: obstack_1grow (rtl_obstack, *name); break;
752       }
753 
754   obstack_1grow (rtl_obstack, '\0');
755   return XOBFINISH (rtl_obstack, const char *);
756 }
757 
758 /* Add one constraint, of any sort, to the tables.  NAME is its name;
759    REGCLASS is the register class, if any; EXP is the expression to
760    test, if any; IS_MEMORY, IS_SPECIAL_MEMORY and IS_ADDRESS indicate
761    memory, special memory, and address constraints, respectively; LOC
762    is the .md file location.
763 
764    Not all combinations of arguments are valid; most importantly,
765    REGCLASS is mutually exclusive with EXP, and
766    IS_MEMORY/IS_SPECIAL_MEMORY/IS_ADDRESS are only meaningful for
767    constraints with EXP.
768 
769    This function enforces all syntactic and semantic rules about what
770    constraints can be defined.  */
771 
772 static void
add_constraint(const char * name,const char * regclass,rtx exp,bool is_memory,bool is_special_memory,bool is_address,file_location loc)773 add_constraint (const char *name, const char *regclass,
774 		rtx exp, bool is_memory, bool is_special_memory,
775 		bool is_address, file_location loc)
776 {
777   struct constraint_data *c, **iter, **slot;
778   const char *p;
779   bool need_mangled_name = false;
780   bool is_const_int;
781   bool is_const_dbl;
782   size_t namelen;
783 
784   if (strcmp (name, "TARGET_MEM_CONSTRAINT") == 0)
785     name = general_mem;
786 
787   if (exp && validate_exp (exp, name, loc))
788     return;
789 
790   for (p = name; *p; p++)
791     if (!ISALNUM (*p))
792       {
793 	if (*p == '<' || *p == '>' || *p == '_')
794 	  need_mangled_name = true;
795 	else
796 	  {
797 	    error_at (loc, "constraint name '%s' must be composed of letters,"
798 		      " digits, underscores, and angle brackets", name);
799 	    return;
800 	  }
801       }
802 
803   if (strchr (generic_constraint_letters, name[0]))
804     {
805       if (name[1] == '\0')
806 	error_at (loc, "constraint letter '%s' cannot be "
807 		  "redefined by the machine description", name);
808       else
809 	error_at (loc, "constraint name '%s' cannot be defined by the machine"
810 		  " description, as it begins with '%c'", name, name[0]);
811       return;
812     }
813 
814 
815   namelen = strlen (name);
816   slot = &constraints_by_letter_table[(unsigned int)name[0]];
817   for (iter = slot; *iter; iter = &(*iter)->next_this_letter)
818     {
819       /* This causes slot to end up pointing to the
820 	 next_this_letter field of the last constraint with a name
821 	 of equal or greater length than the new constraint; hence
822 	 the new constraint will be inserted after all previous
823 	 constraints with names of the same length.  */
824       if ((*iter)->namelen >= namelen)
825 	slot = iter;
826 
827       if (!strcmp ((*iter)->name, name))
828 	{
829 	  error_at (loc, "redefinition of constraint '%s'", name);
830 	  message_at ((*iter)->loc, "previous definition is here");
831 	  return;
832 	}
833       else if (!strncmp ((*iter)->name, name, (*iter)->namelen))
834 	{
835 	  error_at (loc, "defining constraint '%s' here", name);
836 	  message_at ((*iter)->loc, "renders constraint '%s' "
837 		      "(defined here) a prefix", (*iter)->name);
838 	  return;
839 	}
840       else if (!strncmp ((*iter)->name, name, namelen))
841 	{
842 	  error_at (loc, "constraint '%s' is a prefix", name);
843 	  message_at ((*iter)->loc, "of constraint '%s' (defined here)",
844 		      (*iter)->name);
845 	  return;
846 	}
847     }
848 
849   is_const_int = strchr (const_int_constraints, name[0]) != 0;
850   is_const_dbl = strchr (const_dbl_constraints, name[0]) != 0;
851 
852   if (is_const_int || is_const_dbl)
853     {
854       enum rtx_code appropriate_code
855 	= is_const_int ? CONST_INT : CONST_DOUBLE;
856 
857       /* Consider relaxing this requirement in the future.  */
858       if (regclass
859 	  || GET_CODE (exp) != AND
860 	  || GET_CODE (XEXP (exp, 0)) != MATCH_CODE
861 	  || strcmp (XSTR (XEXP (exp, 0), 0),
862 		     GET_RTX_NAME (appropriate_code)))
863 	{
864 	  if (name[1] == '\0')
865 	    error_at (loc, "constraint letter '%c' is reserved "
866 		      "for %s constraints", name[0],
867 		      GET_RTX_NAME (appropriate_code));
868 	  else
869 	    error_at (loc, "constraint names beginning with '%c' "
870 		      "(%s) are reserved for %s constraints",
871 		      name[0], name, GET_RTX_NAME (appropriate_code));
872 	  return;
873 	}
874 
875       if (is_memory)
876 	{
877 	  if (name[1] == '\0')
878 	    error_at (loc, "constraint letter '%c' cannot be a "
879 		      "memory constraint", name[0]);
880 	  else
881 	    error_at (loc, "constraint name '%s' begins with '%c', "
882 		      "and therefore cannot be a memory constraint",
883 		      name, name[0]);
884 	  return;
885 	}
886       else if (is_special_memory)
887 	{
888 	  if (name[1] == '\0')
889 	    error_at (loc, "constraint letter '%c' cannot be a "
890 		      "special memory constraint", name[0]);
891 	  else
892 	    error_at (loc, "constraint name '%s' begins with '%c', "
893 		      "and therefore cannot be a special memory constraint",
894 		      name, name[0]);
895 	  return;
896 	}
897       else if (is_address)
898 	{
899 	  if (name[1] == '\0')
900 	    error_at (loc, "constraint letter '%c' cannot be an "
901 		      "address constraint", name[0]);
902 	  else
903 	    error_at (loc, "constraint name '%s' begins with '%c', "
904 		      "and therefore cannot be an address constraint",
905 		      name, name[0]);
906 	  return;
907 	}
908     }
909 
910 
911   c = XOBNEW (rtl_obstack, struct constraint_data);
912   c->name = name;
913   c->c_name = need_mangled_name ? mangle (name) : name;
914   c->loc = loc;
915   c->namelen = namelen;
916   c->regclass = regclass;
917   c->exp = exp;
918   c->is_register = regclass != 0;
919   c->is_const_int = is_const_int;
920   c->is_const_dbl = is_const_dbl;
921   c->is_extra = !(regclass || is_const_int || is_const_dbl);
922   c->is_memory = is_memory;
923   c->is_special_memory = is_special_memory;
924   c->is_address = is_address;
925   c->maybe_allows_reg = true;
926   c->maybe_allows_mem = true;
927   if (exp)
928     {
929       char codes[NUM_RTX_CODE];
930       compute_test_codes (exp, loc, codes);
931       if (!codes[REG] && !codes[SUBREG])
932 	c->maybe_allows_reg = false;
933       if (!codes[MEM])
934 	c->maybe_allows_mem = false;
935     }
936   c->next_this_letter = *slot;
937   *slot = c;
938 
939   /* Insert this constraint in the list of all constraints in textual
940      order.  */
941   c->next_textual = 0;
942   *last_constraint_ptr = c;
943   last_constraint_ptr = &c->next_textual;
944 
945   constraint_max_namelen = MAX (constraint_max_namelen, strlen (name));
946   have_register_constraints |= c->is_register;
947   have_const_int_constraints |= c->is_const_int;
948   have_extra_constraints |= c->is_extra;
949   have_memory_constraints |= c->is_memory;
950   have_special_memory_constraints |= c->is_special_memory;
951   have_address_constraints |= c->is_address;
952   num_constraints += 1;
953 }
954 
955 /* Process a DEFINE_CONSTRAINT, DEFINE_MEMORY_CONSTRAINT,
956    DEFINE_SPECIAL_MEMORY_CONSTRAINT, or DEFINE_ADDRESS_CONSTRAINT
957    expression, C.  */
958 static void
process_define_constraint(md_rtx_info * info)959 process_define_constraint (md_rtx_info *info)
960 {
961   add_constraint (XSTR (info->def, 0), 0, XEXP (info->def, 2),
962 		  GET_CODE (info->def) == DEFINE_MEMORY_CONSTRAINT,
963 		  GET_CODE (info->def) == DEFINE_SPECIAL_MEMORY_CONSTRAINT,
964 		  GET_CODE (info->def) == DEFINE_ADDRESS_CONSTRAINT,
965 		  info->loc);
966 }
967 
968 /* Process a DEFINE_REGISTER_CONSTRAINT expression, C.  */
969 static void
process_define_register_constraint(md_rtx_info * info)970 process_define_register_constraint (md_rtx_info *info)
971 {
972   add_constraint (XSTR (info->def, 0), XSTR (info->def, 1),
973 		  0, false, false, false, info->loc);
974 }
975 
976 /* Put the constraints into enum order.  We want to keep constraints
977    of the same type together so that query functions can be simple
978    range checks.  */
979 static void
choose_enum_order(void)980 choose_enum_order (void)
981 {
982   struct constraint_data *c;
983 
984   enum_order = XNEWVEC (const constraint_data *, num_constraints);
985   unsigned int next = 0;
986 
987   register_start = next;
988   FOR_ALL_CONSTRAINTS (c)
989     if (c->is_register)
990       enum_order[next++] = c;
991   register_end = next;
992 
993   satisfied_start = next;
994 
995   const_int_start = next;
996   FOR_ALL_CONSTRAINTS (c)
997     if (c->is_const_int)
998       enum_order[next++] = c;
999   const_int_end = next;
1000 
1001   memory_start = next;
1002   FOR_ALL_CONSTRAINTS (c)
1003     if (c->is_memory)
1004       enum_order[next++] = c;
1005   memory_end = next;
1006 
1007   special_memory_start = next;
1008   FOR_ALL_CONSTRAINTS (c)
1009     if (c->is_special_memory)
1010       enum_order[next++] = c;
1011   special_memory_end = next;
1012 
1013   address_start = next;
1014   FOR_ALL_CONSTRAINTS (c)
1015     if (c->is_address)
1016       enum_order[next++] = c;
1017   address_end = next;
1018 
1019   maybe_allows_none_start = next;
1020   FOR_ALL_CONSTRAINTS (c)
1021     if (!c->is_register && !c->is_const_int && !c->is_memory
1022 	&& !c->is_special_memory && !c->is_address
1023 	&& !c->maybe_allows_reg && !c->maybe_allows_mem)
1024       enum_order[next++] = c;
1025   maybe_allows_none_end = next;
1026 
1027   maybe_allows_reg_start = next;
1028   FOR_ALL_CONSTRAINTS (c)
1029     if (!c->is_register && !c->is_const_int && !c->is_memory
1030 	&& !c->is_special_memory && !c->is_address
1031 	&& c->maybe_allows_reg && !c->maybe_allows_mem)
1032       enum_order[next++] = c;
1033   maybe_allows_reg_end = next;
1034 
1035   maybe_allows_mem_start = next;
1036   FOR_ALL_CONSTRAINTS (c)
1037     if (!c->is_register && !c->is_const_int && !c->is_memory
1038 	&& !c->is_special_memory && !c->is_address
1039 	&& !c->maybe_allows_reg && c->maybe_allows_mem)
1040       enum_order[next++] = c;
1041   maybe_allows_mem_end = next;
1042 
1043   FOR_ALL_CONSTRAINTS (c)
1044     if (!c->is_register && !c->is_const_int && !c->is_memory
1045 	&& !c->is_special_memory && !c->is_address
1046 	&& c->maybe_allows_reg && c->maybe_allows_mem)
1047       enum_order[next++] = c;
1048   gcc_assert (next == num_constraints);
1049 }
1050 
1051 /* Write out an enumeration with one entry per machine-specific
1052    constraint.  */
1053 static void
write_enum_constraint_num(void)1054 write_enum_constraint_num (void)
1055 {
1056   fputs ("#define CONSTRAINT_NUM_DEFINED_P 1\n", stdout);
1057   fputs ("enum constraint_num\n"
1058 	 "{\n"
1059 	 "  CONSTRAINT__UNKNOWN = 0", stdout);
1060   for (unsigned int i = 0; i < num_constraints; ++i)
1061     printf (",\n  CONSTRAINT_%s", enum_order[i]->c_name);
1062   puts (",\n  CONSTRAINT__LIMIT\n};\n");
1063 }
1064 
1065 /* Write out a function which looks at a string and determines what
1066    constraint name, if any, it begins with.  */
1067 static void
write_lookup_constraint_1(void)1068 write_lookup_constraint_1 (void)
1069 {
1070   unsigned int i;
1071   puts ("enum constraint_num\n"
1072 	"lookup_constraint_1 (const char *str)\n"
1073 	"{\n"
1074 	"  switch (str[0])\n"
1075 	"    {");
1076 
1077   for (i = 0; i < ARRAY_SIZE (constraints_by_letter_table); i++)
1078     {
1079       struct constraint_data *c = constraints_by_letter_table[i];
1080       if (!c)
1081 	continue;
1082 
1083       printf ("    case '%c':\n", i);
1084       if (c->namelen == 1)
1085 	printf ("      return CONSTRAINT_%s;\n", c->c_name);
1086       else
1087 	{
1088 	  do
1089 	    {
1090 	      printf ("      if (!strncmp (str + 1, \"%s\", %lu))\n"
1091 		      "        return CONSTRAINT_%s;\n",
1092 		      c->name + 1, (unsigned long int) c->namelen - 1,
1093 		      c->c_name);
1094 	      c = c->next_this_letter;
1095 	    }
1096 	  while (c);
1097 	  puts ("      break;");
1098 	}
1099     }
1100 
1101   puts ("    default: break;\n"
1102 	"    }\n"
1103 	"  return CONSTRAINT__UNKNOWN;\n"
1104 	"}\n");
1105 }
1106 
1107 /* Write out an array that maps single-letter characters to their
1108    constraints (if that fits in a character) or 255 if lookup_constraint_1
1109    must be called.  */
1110 static void
write_lookup_constraint_array(void)1111 write_lookup_constraint_array (void)
1112 {
1113   unsigned int i;
1114   printf ("const unsigned char lookup_constraint_array[] = {\n  ");
1115   for (i = 0; i < ARRAY_SIZE (constraints_by_letter_table); i++)
1116     {
1117       if (i != 0)
1118 	printf (",\n  ");
1119       struct constraint_data *c = constraints_by_letter_table[i];
1120       if (!c)
1121 	printf ("CONSTRAINT__UNKNOWN");
1122       else if (c->namelen == 1)
1123 	printf ("MIN ((int) CONSTRAINT_%s, (int) UCHAR_MAX)", c->c_name);
1124       else
1125 	printf ("UCHAR_MAX");
1126     }
1127   printf ("\n};\n\n");
1128 }
1129 
1130 /* Write out a function which looks at a string and determines what
1131    the constraint name length is.  */
1132 static void
write_insn_constraint_len(void)1133 write_insn_constraint_len (void)
1134 {
1135   unsigned int i;
1136 
1137   puts ("static inline size_t\n"
1138 	"insn_constraint_len (char fc, const char *str ATTRIBUTE_UNUSED)\n"
1139 	"{\n"
1140 	"  switch (fc)\n"
1141 	"    {");
1142 
1143   for (i = 0; i < ARRAY_SIZE (constraints_by_letter_table); i++)
1144     {
1145       struct constraint_data *c = constraints_by_letter_table[i];
1146 
1147       if (!c
1148       	  || c->namelen == 1)
1149 	continue;
1150 
1151       /* Constraints with multiple characters should have the same
1152 	 length.  */
1153       {
1154 	struct constraint_data *c2 = c->next_this_letter;
1155 	size_t len = c->namelen;
1156 	while (c2)
1157 	  {
1158 	    if (c2->namelen != len)
1159 	      error ("Multi-letter constraints with first letter '%c' "
1160 		     "should have same length", i);
1161 	    c2 = c2->next_this_letter;
1162 	  }
1163       }
1164 
1165       printf ("    case '%c': return %lu;\n",
1166 	      i, (unsigned long int) c->namelen);
1167     }
1168 
1169   puts ("    default: break;\n"
1170 	"    }\n"
1171 	"  return 1;\n"
1172 	"}\n");
1173 }
1174 
1175 /* Write out the function which computes the register class corresponding
1176    to a register constraint.  */
1177 static void
write_reg_class_for_constraint_1(void)1178 write_reg_class_for_constraint_1 (void)
1179 {
1180   struct constraint_data *c;
1181 
1182   puts ("enum reg_class\n"
1183 	"reg_class_for_constraint_1 (enum constraint_num c)\n"
1184 	"{\n"
1185 	"  switch (c)\n"
1186 	"    {");
1187 
1188   FOR_ALL_CONSTRAINTS (c)
1189     if (c->is_register)
1190       printf ("    case CONSTRAINT_%s: return %s;\n", c->c_name, c->regclass);
1191 
1192   puts ("    default: break;\n"
1193 	"    }\n"
1194 	"  return NO_REGS;\n"
1195 	"}\n");
1196 }
1197 
1198 /* Write out the functions which compute whether a given value matches
1199    a given non-register constraint.  */
1200 static void
write_tm_constrs_h(void)1201 write_tm_constrs_h (void)
1202 {
1203   struct constraint_data *c;
1204 
1205   printf ("\
1206 /* Generated automatically by the program '%s'\n\
1207    from the machine description file '%s'.  */\n\n", progname, in_fname);
1208 
1209   puts ("\
1210 #ifndef GCC_TM_CONSTRS_H\n\
1211 #define GCC_TM_CONSTRS_H\n");
1212 
1213   FOR_ALL_CONSTRAINTS (c)
1214     if (!c->is_register)
1215       {
1216 	bool needs_ival = needs_variable (c->exp, "ival");
1217 	bool needs_hval = needs_variable (c->exp, "hval");
1218 	bool needs_lval = needs_variable (c->exp, "lval");
1219 	bool needs_rval = needs_variable (c->exp, "rval");
1220 	bool needs_mode = (needs_variable (c->exp, "mode")
1221 			   || needs_hval || needs_lval || needs_rval);
1222 	bool needs_op = (needs_variable (c->exp, "op")
1223 			 || needs_ival || needs_mode);
1224 
1225 	printf ("static inline bool\n"
1226 		"satisfies_constraint_%s (rtx %s)\n"
1227 		"{\n", c->c_name,
1228 		needs_op ? "op" : "ARG_UNUSED (op)");
1229 	if (needs_mode)
1230 	  puts ("  machine_mode mode = GET_MODE (op);");
1231 	if (needs_ival)
1232 	  puts ("  HOST_WIDE_INT ival = 0;");
1233 	if (needs_hval)
1234 	  puts ("  HOST_WIDE_INT hval = 0;");
1235 	if (needs_lval)
1236 	  puts ("  unsigned HOST_WIDE_INT lval = 0;");
1237 	if (needs_rval)
1238 	  puts ("  const REAL_VALUE_TYPE *rval = 0;");
1239 
1240 	if (needs_ival)
1241 	  puts ("  if (CONST_INT_P (op))\n"
1242 		"    ival = INTVAL (op);");
1243 #if TARGET_SUPPORTS_WIDE_INT
1244 	if (needs_lval || needs_hval)
1245 	  error ("you can't use lval or hval");
1246 #else
1247 	if (needs_hval)
1248 	  puts ("  if (GET_CODE (op) == CONST_DOUBLE && mode == VOIDmode)"
1249 		"    hval = CONST_DOUBLE_HIGH (op);");
1250 	if (needs_lval)
1251 	  puts ("  if (GET_CODE (op) == CONST_DOUBLE && mode == VOIDmode)"
1252 		"    lval = CONST_DOUBLE_LOW (op);");
1253 #endif
1254 	if (needs_rval)
1255 	  puts ("  if (GET_CODE (op) == CONST_DOUBLE && mode != VOIDmode)"
1256 		"    rval = CONST_DOUBLE_REAL_VALUE (op);");
1257 
1258 	write_predicate_stmts (c->exp);
1259 	fputs ("}\n", stdout);
1260       }
1261   puts ("#endif /* tm-constrs.h */");
1262 }
1263 
1264 /* Write out the wrapper function, constraint_satisfied_p, that maps
1265    a CONSTRAINT_xxx constant to one of the predicate functions generated
1266    above.  */
1267 static void
write_constraint_satisfied_p_array(void)1268 write_constraint_satisfied_p_array (void)
1269 {
1270   if (satisfied_start == num_constraints)
1271     return;
1272 
1273   printf ("bool (*constraint_satisfied_p_array[]) (rtx) = {\n  ");
1274   for (unsigned int i = satisfied_start; i < num_constraints; ++i)
1275     {
1276       if (i != satisfied_start)
1277 	printf (",\n  ");
1278       printf ("satisfies_constraint_%s", enum_order[i]->c_name);
1279     }
1280   printf ("\n};\n\n");
1281 }
1282 
1283 /* Write out the function which computes whether a given value matches
1284    a given CONST_INT constraint.  This doesn't just forward to
1285    constraint_satisfied_p because caller passes the INTVAL, not the RTX.  */
1286 static void
write_insn_const_int_ok_for_constraint(void)1287 write_insn_const_int_ok_for_constraint (void)
1288 {
1289   struct constraint_data *c;
1290 
1291   puts ("bool\n"
1292 	"insn_const_int_ok_for_constraint (HOST_WIDE_INT ival, "
1293 	                                  "enum constraint_num c)\n"
1294 	"{\n"
1295 	"  switch (c)\n"
1296 	"    {");
1297 
1298   FOR_ALL_CONSTRAINTS (c)
1299     if (c->is_const_int)
1300       {
1301 	printf ("    case CONSTRAINT_%s:\n      return ", c->c_name);
1302 	/* c->exp is guaranteed to be (and (match_code "const_int") (...));
1303 	   we know at this point that we have a const_int, so we need not
1304 	   bother with that part of the test.  */
1305 	write_predicate_expr (XEXP (c->exp, 1));
1306 	fputs (";\n\n", stdout);
1307       }
1308 
1309   puts ("    default: break;\n"
1310 	"    }\n"
1311 	"  return false;\n"
1312 	"}\n");
1313 }
1314 
1315 /* Write a definition for a function NAME that returns true if a given
1316    constraint_num is in the range [START, END).  */
1317 static void
write_range_function(const char * name,unsigned int start,unsigned int end)1318 write_range_function (const char *name, unsigned int start, unsigned int end)
1319 {
1320   printf ("static inline bool\n");
1321   if (start != end)
1322     printf ("%s (enum constraint_num c)\n"
1323 	    "{\n"
1324 	    "  return c >= CONSTRAINT_%s && c <= CONSTRAINT_%s;\n"
1325 	    "}\n\n",
1326 	    name, enum_order[start]->c_name, enum_order[end - 1]->c_name);
1327   else
1328     printf ("%s (enum constraint_num)\n"
1329 	    "{\n"
1330 	    "  return false;\n"
1331 	    "}\n\n", name);
1332 }
1333 
1334 /* Write a definition for insn_extra_constraint_allows_reg_mem function.  */
1335 static void
write_allows_reg_mem_function(void)1336 write_allows_reg_mem_function (void)
1337 {
1338   printf ("static inline void\n"
1339 	  "insn_extra_constraint_allows_reg_mem (enum constraint_num c,\n"
1340 	  "\t\t\t\t      bool *allows_reg, bool *allows_mem)\n"
1341 	  "{\n");
1342   if (maybe_allows_none_start != maybe_allows_none_end)
1343     printf ("  if (c >= CONSTRAINT_%s && c <= CONSTRAINT_%s)\n"
1344 	    "    return;\n",
1345 	    enum_order[maybe_allows_none_start]->c_name,
1346 	    enum_order[maybe_allows_none_end - 1]->c_name);
1347   if (maybe_allows_reg_start != maybe_allows_reg_end)
1348     printf ("  if (c >= CONSTRAINT_%s && c <= CONSTRAINT_%s)\n"
1349 	    "    {\n"
1350 	    "      *allows_reg = true;\n"
1351 	    "      return;\n"
1352 	    "    }\n",
1353 	    enum_order[maybe_allows_reg_start]->c_name,
1354 	    enum_order[maybe_allows_reg_end - 1]->c_name);
1355   if (maybe_allows_mem_start != maybe_allows_mem_end)
1356     printf ("  if (c >= CONSTRAINT_%s && c <= CONSTRAINT_%s)\n"
1357 	    "    {\n"
1358 	    "      *allows_mem = true;\n"
1359 	    "      return;\n"
1360 	    "    }\n",
1361 	    enum_order[maybe_allows_mem_start]->c_name,
1362 	    enum_order[maybe_allows_mem_end - 1]->c_name);
1363   printf ("  (void) c;\n"
1364 	  "  *allows_reg = true;\n"
1365 	  "  *allows_mem = true;\n"
1366 	  "}\n\n");
1367 }
1368 
1369 /* VEC is a list of key/value pairs, with the keys being lower bounds
1370    of a range.  Output a decision tree that handles the keys covered by
1371    [VEC[START], VEC[END]), returning FALLBACK for keys lower then VEC[START]'s.
1372    INDENT is the number of spaces to indent the code.  */
1373 static void
print_type_tree(const vec<std::pair<unsigned int,const char * >> & vec,unsigned int start,unsigned int end,const char * fallback,unsigned int indent)1374 print_type_tree (const vec <std::pair <unsigned int, const char *> > &vec,
1375 		 unsigned int start, unsigned int end, const char *fallback,
1376 		 unsigned int indent)
1377 {
1378   while (start < end)
1379     {
1380       unsigned int mid = (start + end) / 2;
1381       printf ("%*sif (c >= CONSTRAINT_%s)\n",
1382 	      indent, "", enum_order[vec[mid].first]->c_name);
1383       if (mid + 1 == end)
1384 	print_type_tree (vec, mid + 1, end, vec[mid].second, indent + 2);
1385       else
1386 	{
1387 	  printf ("%*s{\n", indent + 2, "");
1388 	  print_type_tree (vec, mid + 1, end, vec[mid].second, indent + 4);
1389 	  printf ("%*s}\n", indent + 2, "");
1390 	}
1391       end = mid;
1392     }
1393   printf ("%*sreturn %s;\n", indent, "", fallback);
1394 }
1395 
1396 /* Write tm-preds.h.  Unfortunately, it is impossible to forward-declare
1397    an enumeration in portable C, so we have to condition all these
1398    prototypes on HAVE_MACHINE_MODES.  */
1399 static void
write_tm_preds_h(void)1400 write_tm_preds_h (void)
1401 {
1402   struct pred_data *p;
1403 
1404   printf ("\
1405 /* Generated automatically by the program '%s'\n\
1406    from the machine description file '%s'.  */\n\n", progname, in_fname);
1407 
1408   puts ("\
1409 #ifndef GCC_TM_PREDS_H\n\
1410 #define GCC_TM_PREDS_H\n\
1411 \n\
1412 #ifdef HAVE_MACHINE_MODES");
1413 
1414   FOR_ALL_PREDICATES (p)
1415     printf ("extern int %s (rtx, machine_mode);\n", p->name);
1416 
1417   puts ("#endif /* HAVE_MACHINE_MODES */\n");
1418 
1419   if (constraint_max_namelen > 0)
1420     {
1421       write_enum_constraint_num ();
1422       puts ("extern enum constraint_num lookup_constraint_1 (const char *);\n"
1423 	    "extern const unsigned char lookup_constraint_array[];\n"
1424 	    "\n"
1425 	    "/* Return the constraint at the beginning of P, or"
1426 	    " CONSTRAINT__UNKNOWN if it\n"
1427 	    "   isn't recognized.  */\n"
1428 	    "\n"
1429 	    "static inline enum constraint_num\n"
1430 	    "lookup_constraint (const char *p)\n"
1431 	    "{\n"
1432 	    "  unsigned int index = lookup_constraint_array"
1433 	    "[(unsigned char) *p];\n"
1434 	    "  return (index == UCHAR_MAX\n"
1435 	    "          ? lookup_constraint_1 (p)\n"
1436 	    "          : (enum constraint_num) index);\n"
1437 	    "}\n");
1438       if (satisfied_start == num_constraints)
1439 	puts ("/* Return true if X satisfies constraint C.  */\n"
1440 	      "\n"
1441 	      "static inline bool\n"
1442 	      "constraint_satisfied_p (rtx, enum constraint_num)\n"
1443 	      "{\n"
1444 	      "  return false;\n"
1445 	      "}\n");
1446       else
1447 	printf ("extern bool (*constraint_satisfied_p_array[]) (rtx);\n"
1448 		"\n"
1449 		"/* Return true if X satisfies constraint C.  */\n"
1450 		"\n"
1451 		"static inline bool\n"
1452 		"constraint_satisfied_p (rtx x, enum constraint_num c)\n"
1453 		"{\n"
1454 		"  int i = (int) c - (int) CONSTRAINT_%s;\n"
1455 		"  return i >= 0 && constraint_satisfied_p_array[i] (x);\n"
1456 		"}\n"
1457 		"\n",
1458 		enum_order[satisfied_start]->name);
1459 
1460       write_range_function ("insn_extra_register_constraint",
1461 			    register_start, register_end);
1462       write_range_function ("insn_extra_memory_constraint",
1463 			    memory_start, memory_end);
1464       write_range_function ("insn_extra_special_memory_constraint",
1465 			    special_memory_start, special_memory_end);
1466       write_range_function ("insn_extra_address_constraint",
1467 			    address_start, address_end);
1468       write_allows_reg_mem_function ();
1469 
1470       if (constraint_max_namelen > 1)
1471         {
1472 	  write_insn_constraint_len ();
1473 	  puts ("#define CONSTRAINT_LEN(c_,s_) "
1474 		"insn_constraint_len (c_,s_)\n");
1475 	}
1476       else
1477 	puts ("#define CONSTRAINT_LEN(c_,s_) 1\n");
1478       if (have_register_constraints)
1479 	puts ("extern enum reg_class reg_class_for_constraint_1 "
1480 	      "(enum constraint_num);\n"
1481 	      "\n"
1482 	      "static inline enum reg_class\n"
1483 	      "reg_class_for_constraint (enum constraint_num c)\n"
1484 	      "{\n"
1485 	      "  if (insn_extra_register_constraint (c))\n"
1486 	      "    return reg_class_for_constraint_1 (c);\n"
1487 	      "  return NO_REGS;\n"
1488 	      "}\n");
1489       else
1490 	puts ("static inline enum reg_class\n"
1491 	      "reg_class_for_constraint (enum constraint_num)\n"
1492 	      "{\n"
1493 	      "  return NO_REGS;\n"
1494 	      "}\n");
1495       if (have_const_int_constraints)
1496 	puts ("extern bool insn_const_int_ok_for_constraint "
1497 	      "(HOST_WIDE_INT, enum constraint_num);\n"
1498 	      "#define CONST_OK_FOR_CONSTRAINT_P(v_,c_,s_) \\\n"
1499 	      "    insn_const_int_ok_for_constraint (v_, "
1500 	      "lookup_constraint (s_))\n");
1501       else
1502 	puts ("static inline bool\n"
1503 	      "insn_const_int_ok_for_constraint (HOST_WIDE_INT,"
1504 	      " enum constraint_num)\n"
1505 	      "{\n"
1506 	      "  return false;\n"
1507 	      "}\n");
1508 
1509       puts ("enum constraint_type\n"
1510 	    "{\n"
1511 	    "  CT_REGISTER,\n"
1512 	    "  CT_CONST_INT,\n"
1513 	    "  CT_MEMORY,\n"
1514 	    "  CT_SPECIAL_MEMORY,\n"
1515 	    "  CT_ADDRESS,\n"
1516 	    "  CT_FIXED_FORM\n"
1517 	    "};\n"
1518 	    "\n"
1519 	    "static inline enum constraint_type\n"
1520 	    "get_constraint_type (enum constraint_num c)\n"
1521 	    "{");
1522       auto_vec <std::pair <unsigned int, const char *>, 4> values;
1523       if (const_int_start != const_int_end)
1524 	values.safe_push (std::make_pair (const_int_start, "CT_CONST_INT"));
1525       if (memory_start != memory_end)
1526 	values.safe_push (std::make_pair (memory_start, "CT_MEMORY"));
1527       if (special_memory_start != special_memory_end)
1528 	values.safe_push (std::make_pair (special_memory_start, "CT_SPECIAL_MEMORY"));
1529       if (address_start != address_end)
1530 	values.safe_push (std::make_pair (address_start, "CT_ADDRESS"));
1531       if (address_end != num_constraints)
1532 	values.safe_push (std::make_pair (address_end, "CT_FIXED_FORM"));
1533       print_type_tree (values, 0, values.length (), "CT_REGISTER", 2);
1534       puts ("}");
1535     }
1536 
1537   puts ("#endif /* tm-preds.h */");
1538 }
1539 
1540 /* Write insn-preds.c.
1541    N.B. the list of headers to include was copied from genrecog; it
1542    may not be ideal.
1543 
1544    FUTURE: Write #line markers referring back to the machine
1545    description.  (Can't practically do this now since we don't know
1546    the line number of the C block - just the line number of the enclosing
1547    expression.)  */
1548 static void
write_insn_preds_c(void)1549 write_insn_preds_c (void)
1550 {
1551   struct pred_data *p;
1552 
1553   printf ("\
1554 /* Generated automatically by the program '%s'\n\
1555    from the machine description file '%s'.  */\n\n", progname, in_fname);
1556 
1557   puts ("\
1558 #include \"config.h\"\n\
1559 #include \"system.h\"\n\
1560 #include \"coretypes.h\"\n\
1561 #include \"backend.h\"\n\
1562 #include \"predict.h\"\n\
1563 #include \"tree.h\"\n\
1564 #include \"rtl.h\"\n\
1565 #include \"alias.h\"\n\
1566 #include \"varasm.h\"\n\
1567 #include \"stor-layout.h\"\n\
1568 #include \"calls.h\"\n\
1569 #include \"tm_p.h\"\n\
1570 #include \"insn-config.h\"\n\
1571 #include \"recog.h\"\n\
1572 #include \"output.h\"\n\
1573 #include \"flags.h\"\n\
1574 #include \"df.h\"\n\
1575 #include \"resource.h\"\n\
1576 #include \"diagnostic-core.h\"\n\
1577 #include \"reload.h\"\n\
1578 #include \"regs.h\"\n\
1579 #include \"emit-rtl.h\"\n\
1580 #include \"tm-constrs.h\"\n");
1581 
1582   FOR_ALL_PREDICATES (p)
1583     write_one_predicate_function (p);
1584 
1585   if (constraint_max_namelen > 0)
1586     {
1587       write_lookup_constraint_1 ();
1588       write_lookup_constraint_array ();
1589       if (have_register_constraints)
1590 	write_reg_class_for_constraint_1 ();
1591       write_constraint_satisfied_p_array ();
1592 
1593       if (have_const_int_constraints)
1594 	write_insn_const_int_ok_for_constraint ();
1595     }
1596 }
1597 
1598 /* Argument parsing.  */
1599 static bool gen_header;
1600 static bool gen_constrs;
1601 
1602 static bool
parse_option(const char * opt)1603 parse_option (const char *opt)
1604 {
1605   if (!strcmp (opt, "-h"))
1606     {
1607       gen_header = true;
1608       return 1;
1609     }
1610   else if (!strcmp (opt, "-c"))
1611     {
1612       gen_constrs = true;
1613       return 1;
1614     }
1615   else
1616     return 0;
1617 }
1618 
1619 /* Master control.  */
1620 int
main(int argc,char ** argv)1621 main (int argc, char **argv)
1622 {
1623   progname = argv[0];
1624   if (argc <= 1)
1625     fatal ("no input file name");
1626   if (!init_rtx_reader_args_cb (argc, argv, parse_option))
1627     return FATAL_EXIT_CODE;
1628 
1629   md_rtx_info info;
1630   while (read_md_rtx (&info))
1631     switch (GET_CODE (info.def))
1632       {
1633       case DEFINE_PREDICATE:
1634       case DEFINE_SPECIAL_PREDICATE:
1635 	process_define_predicate (&info);
1636 	break;
1637 
1638       case DEFINE_CONSTRAINT:
1639       case DEFINE_MEMORY_CONSTRAINT:
1640       case DEFINE_SPECIAL_MEMORY_CONSTRAINT:
1641       case DEFINE_ADDRESS_CONSTRAINT:
1642 	process_define_constraint (&info);
1643 	break;
1644 
1645       case DEFINE_REGISTER_CONSTRAINT:
1646 	process_define_register_constraint (&info);
1647 	break;
1648 
1649       default:
1650 	break;
1651       }
1652 
1653   choose_enum_order ();
1654 
1655   if (gen_header)
1656     write_tm_preds_h ();
1657   else if (gen_constrs)
1658     write_tm_constrs_h ();
1659   else
1660     write_insn_preds_c ();
1661 
1662   if (have_error || ferror (stdout) || fflush (stdout) || fclose (stdout))
1663     return FATAL_EXIT_CODE;
1664 
1665   return SUCCESS_EXIT_CODE;
1666 }
1667