fixed the usage of real register names
[libfirm] / ir / be / scripts / generate_regalloc_if.pl
1 #!/usr/bin/perl -w
2
3 # This script generates C code which creates ands sets up functions and
4 # data structures for the register allocator.
5 # Creation: 2005/11/14
6 # $Id$
7
8 use strict;
9 use Data::Dumper;
10
11 my $specfile   = $ARGV[0];
12 my $target_dir = $ARGV[1];
13
14 our $arch;
15 our %reg_classes;
16 our %nodes;
17 our %cpu;
18
19 # include spec file
20
21 my $return;
22
23 no strict "subs";
24 unless ($return = do $specfile) {
25         warn "couldn't parse $specfile: $@" if $@;
26         warn "couldn't do $specfile: $!"    unless defined $return;
27         warn "couldn't run $specfile"       unless $return;
28 }
29 use strict "subs";
30
31 my $target_c   = $target_dir."/gen_".$arch."_regalloc_if.c";
32 my $target_h   = $target_dir."/gen_".$arch."_regalloc_if.h";
33 my $target_h_t = $target_dir."/gen_".$arch."_regalloc_if_t.h";
34
35 # helper function
36 sub translate_reg_type {
37         my $t = shift;
38
39         if ($t == 0) {
40                 return "arch_register_type_none";
41         }
42         else {
43                 my @types;
44
45                 if ($t & 1) {
46                         push(@types, "arch_register_type_caller_save");
47                 }
48
49                 if ($t & 2) {
50                         push(@types, "arch_register_type_callee_save");
51                 }
52
53                 if ($t & 4) {
54                         push(@types, "arch_register_type_ignore");
55                 }
56
57                 if ($t & 8) {
58                         push(@types, "arch_register_type_joker");
59                 }
60
61                 if ($t & 16) {
62                         push(@types, "arch_register_type_virtual");
63                 }
64
65                 return join(" | ", @types);
66         }
67 }
68
69 # stacks for output
70 my @obst_regtypes_def; # stack for the register type variables definitions
71 my @obst_regtypes_decl;# stack for the register type variables declarations
72 my @obst_regclasses;   # stack for the register class variables
73 my @obst_classdef;     # stack to define a name for a class index
74 my @obst_regdef;       # stack to define a name for a register index
75 my @obst_reginit;      # stack for the register type inits
76 my @obst_req;          # stack for the register requirements
77 my @obst_limit_func;   # stack for functions to return a subset of a register class
78 my @obst_defreq_head;  # stack for prototypes of default requirement function
79 my @obst_header_all;   # stack for some extern struct defs needed for bearch_$arch include
80 my @obst_requirement_def;  # stack for requirement name defines
81
82 my $numregs;
83 my $class_ptr;
84 my $class_idx = 0;
85
86 my $tmp;
87
88 my %reg2class;
89
90 # there is a default NONE requirement
91 $tmp = "/* Default NONE register requirements */\n";
92 $tmp .= "const $arch\_register_req_t $arch\_default_req_none = {\n";
93 $tmp .= "  {\n";
94 $tmp .= "    arch_register_req_type_none,  /* register type  */\n";
95 $tmp .= "    NULL,                         /* register class */\n";
96 $tmp .= "    NULL,                         /* limit function */\n";
97 $tmp .= "    NULL,                         /* limit environment */\n";
98 $tmp .= "    NULL,                         /* node for same */\n";
99 $tmp .= "    NULL                          /* node for different */\n";
100 $tmp .= "  },\n";
101 $tmp .= "  0,                              /* same pos */\n";
102 $tmp .= "  0                               /* different pos */\n";
103 $tmp .= "};\n\n";
104 push(@obst_req, $tmp);
105 push(@obst_header_all, "extern const $arch\_register_req_t $arch\_default_req_none;\n");
106
107 push(@obst_classdef, "enum reg_classes {\n");
108
109 my $class_mode;
110
111 # generate register type and class variable, init function and default requirements
112 foreach my $class_name (keys(%reg_classes)) {
113         my @class         = @{ $reg_classes{"$class_name"} };
114         my $old_classname = $class_name;
115
116         $class_name = $arch."_".$class_name;
117         $numregs    = "N_".$class_name."_REGS";
118         $class_ptr  = "&".$arch."_reg_classes[CLASS_".$class_name."]";
119         $class_mode = pop(@class)->{"mode"};
120
121         push(@obst_regtypes_decl, "extern arch_register_t ".$class_name."_regs[$numregs];\n");
122         push(@obst_regtypes_def, "arch_register_t ".$class_name."_regs[$numregs];\n");
123
124         push(@obst_classdef, "  CLASS_$class_name = $class_idx,\n");
125         push(@obst_regclasses, "{ \"$class_name\", $numregs, NULL, ".$class_name."_regs }");
126
127         # there is a default NORMAL requirement for each class
128         $tmp  = "/* Default NORMAL register requirements for class $class_name */\n";
129         $tmp .= "const $arch\_register_req_t $arch\_default_req_$class_name = {\n";
130         $tmp .= "  {\n";
131         $tmp .= "    arch_register_req_type_normal,\n";
132         $tmp .= "    $class_ptr,\n";
133         $tmp .= "    NULL,                    /* limit function */ \n";
134         $tmp .= "    NULL,                    /* limit environment */\n";
135         $tmp .= "    NULL,                    /* node for same */\n";
136         $tmp .= "    NULL                     /* node for different */\n";
137         $tmp .= "  },\n";
138         $tmp .= "  0,                         /* same pos */\n";
139         $tmp .= "  0                          /* different pos */\n";
140         $tmp .= "};\n\n";
141         push(@obst_req, $tmp);
142         push(@obst_header_all, "extern const $arch\_register_req_t $arch\_default_req_$class_name;\n");
143
144         my $idx = 0;
145         push(@obst_reginit, "  /* Init of all registers in class '$class_name' */\n\n");
146         push(@obst_reginit, "  /* set largest possible mode for '$class_name' */\n");
147         push(@obst_reginit, "  $arch\_reg_classes[CLASS_".$class_name."].mode = $class_mode;\n\n");
148         push(@obst_regdef, "enum reg_".$class_name."_values {\n");
149         foreach (@class) {
150                 # For each class we build for each of it's member registers a limit function
151                 # which limits the class to this particular register. We also build the
152                 # corresponding requirement structs.
153                 # We need those functions to set register requirements on demand in transformation
154                 # esp. for Call and RegParams where we can mix int and float parameters.
155
156                 my $limit_func_name = $arch."_limit_".$class_name."_".$_->{"name"};
157
158                 # push the function prototype
159                 $tmp = "void $limit_func_name(void *_unused, bitset_t *bs)";
160                 push(@obst_defreq_head, $tmp.";\n");
161
162                 # push the function definition
163                 $tmp .= " {\n";
164                 $tmp .= "    bs = bitset_clear_all(bs);\n";
165                 $tmp .= "    bitset_set(bs, REG_".uc($_->{"name"}).");\n";  # REGISTER to index assignment is done some lines down
166                 $tmp .= "}\n\n";
167                 push(@obst_limit_func, $tmp);
168
169                 # push the default requirement struct
170                 $tmp  = "const $arch\_register_req_t $arch\_default_req_$class_name\_".$_->{"name"}." = {\n";
171                 $tmp .= "  {\n";
172                 $tmp .= "    arch_register_req_type_limited,\n";
173                 $tmp .= "    $class_ptr,\n";
174                 $tmp .= "    $limit_func_name,\n";
175                 $tmp .= "    NULL,                     /* limit environment */\n";
176                 $tmp .= "    NULL,                     /* node for same */\n";
177                 $tmp .= "    NULL                      /* node for different */\n";
178                 $tmp .= "  },\n";
179                 $tmp .= "  0,                          /* same pos */\n";
180                 $tmp .= "  0                           /* different pos */\n";
181                 $tmp .= "};\n\n";
182                 push(@obst_req, $tmp);
183                 push(@obst_header_all,"extern const $arch\_register_req_t $arch\_default_req_$class_name\_".$_->{"name"}.";\n");
184
185                 # realname is name if not set by user
186                 $_->{"realname"} = $_->{"name"} if (! exists($_->{"realname"}));
187
188                 $reg2class{$_->{"name"}} = { "class" => $old_classname, "index" => $idx }; # remember reg to class for later use
189                 push(@obst_regdef, "  REG_".uc($_->{"name"})." = $idx,\n");
190                 push(@obst_reginit, "  ".$class_name."_regs[$idx].name      = \"".$_->{"realname"}."\";\n");
191                 push(@obst_reginit, "  ".$class_name."_regs[$idx].reg_class = $class_ptr;\n");
192                 push(@obst_reginit, "  ".$class_name."_regs[$idx].index     = $idx;\n");
193                 push(@obst_reginit, "  ".$class_name."_regs[$idx].type      = ".translate_reg_type($_->{"type"}).";\n");
194                 push(@obst_reginit, "  ".$class_name."_regs[$idx].data      = ".get_execunit_variable_name($_->{"unit"}).";\n");
195                 push(@obst_reginit, "\n");
196                 $idx++;
197         }
198         push(@obst_regdef, "  $numregs = $idx\n");
199         push(@obst_regdef, "};\n\n");
200
201         $class_idx++;
202 }
203
204 push(@obst_classdef, "  N_CLASSES = ".scalar(keys(%reg_classes))."\n");
205 push(@obst_classdef, "};\n\n");
206
207 # generate node-register constraints
208 foreach my $op (keys(%nodes)) {
209         my %n = %{ $nodes{"$op"} };
210
211         next if (!exists($n{"reg_req"}));
212
213         $op = $arch."_".$op;
214
215         push(@obst_req, "/* IN requirements for '$op' */\n");
216         # check for argument requirements
217         if (exists($n{"reg_req"}{"in"})) {
218                 generate_requirements(\%n, $op, "in");
219         }
220
221         push(@obst_req, "/* OUT requirements for '$op' */\n");
222         # check for result requirements
223         if (exists($n{"reg_req"}{"out"})) {
224                 generate_requirements(\%n, $op, "out");
225         }
226 }
227
228
229
230 # generate header _t (internal usage) file
231 open(OUT, ">$target_h_t") || die("Could not open $target_h_t, reason: $!\n");
232
233 my $creation_time = localtime(time());
234
235 $tmp = uc($arch);
236
237 print OUT<<EOF;
238 #ifndef _GEN_$tmp\_REGALLOC_IF_T_H_
239 #define _GEN_$tmp\_REGALLOC_IF_T_H_
240
241 /**
242  * Generated register classes from spec.
243  *
244  * DO NOT EDIT THIS FILE, your changes will be lost.
245  * Edit $specfile instead.
246  * created by: $0 $specfile $target_dir
247  * date:       $creation_time
248  */
249
250 EOF
251
252 print OUT @obst_requirement_def;
253
254 print OUT "\n#endif /* _GEN_$tmp\_REGALLOC_IF_T_H_ */\n";
255
256
257
258 # generate header (external usage) file
259 open(OUT, ">$target_h") || die("Could not open $target_h, reason: $!\n");
260
261 $creation_time = localtime(time());
262
263 print OUT<<EOF;
264 #ifndef _GEN_$tmp\_REGALLOC_IF_H_
265 #define _GEN_$tmp\_REGALLOC_IF_H_
266
267 /**
268  * Contains additional external requirements defs for external includes.
269  *
270  * DO NOT EDIT THIS FILE, your changes will be lost.
271  * Edit $specfile instead.
272  * created by: $0 $specfile $target_dir
273  * date:       $creation_time
274  */
275
276 #include "../bearch.h"
277 #include "$arch\_nodes_attr.h"
278
279 EOF
280
281 print OUT @obst_regdef, "\n";
282
283 print OUT @obst_classdef, "\n";
284
285 print OUT @obst_regtypes_decl, "\n";
286
287 print OUT "extern arch_register_class_t $arch\_reg_classes[N_CLASSES];\n\n";
288
289 print OUT "void ".$arch."_register_init(void *isa_ptr);\n\n";
290
291 print OUT @obst_header_all, "\n";
292
293 print OUT @obst_defreq_head, "\n";
294
295 print OUT "\n#endif /* _GEN_$tmp\_REGALLOC_IF_H_ */\n";
296
297 close(OUT);
298
299
300
301 # generate c file
302 open(OUT, ">$target_c") || die("Could not open $target_c, reason: $!\n");
303
304 $creation_time = localtime(time());
305
306 print OUT<<EOF;
307 /**
308  * The generated interface for the register allocator.
309  * Contains register classes and types and register constraints
310  * for all nodes where constraints were given in spec.
311  *
312  * DO NOT EDIT THIS FILE, your changes will be lost.
313  * Edit $specfile instead.
314  * created by: $0 $specfile $target_dir
315  * date:       $creation_time
316  */
317
318 #include "gen_$arch\_regalloc_if.h"
319 #include "gen_$arch\_machine.h"  /* we need this, as there can be units assigned to registers */
320 #include "bearch_$arch\_t.h"     /* we need this to put the caller saved registers into the isa set */
321 #include "$arch\_map_regs.h"
322 #include "irmode.h"
323
324 EOF
325
326 print OUT "arch_register_class_t $arch\_reg_classes[] = {\n  ".join(",\n  ", @obst_regclasses)."\n};\n\n";
327
328 print OUT @obst_regtypes_def, "\n";
329
330 print OUT "void ".$arch."_register_init(void *isa_ptr) {\n";
331 print OUT @obst_reginit;
332 print OUT "}\n\n";
333
334 print OUT @obst_limit_func;
335
336 print OUT @obst_req;
337
338 close(OUT);
339
340 ###
341 # Remember the register class for each index in the given requirements.
342 # We need this information for requirements like "in_sX" or "out_dX"
343 # @return array of classes corresponding to the requirement for each index
344 ###
345 sub build_inout_idx_class {
346         my $n     = shift;
347         my $op    = shift;
348         my $inout = shift;
349         my @idx_class;
350
351         if (exists($n->{"reg_req"}{"$inout"})) {
352                 my @reqs = @{ $n->{"reg_req"}{"$inout"} };
353
354                 for (my $idx = 0; $idx <= $#reqs; $idx++) {
355                         my $class = undef;
356
357                         if ($reqs[$idx] eq "none") {
358                                 $class = "none";
359                         }
360                         elsif (is_reg_class($reqs[$idx])) {
361                                 $class = $reqs[$idx];
362                         }
363                         else {
364                                 my @regs = split(/ /, $reqs[$idx]);
365 GET_CLASS:              foreach my $reg (@regs) {
366                                         if ($reg =~ /!?(in|out)\_r\d+/ || $reg =~ /!in/) {
367                                                 $class = "UNKNOWN_CLASS";
368                                         }
369                                         else {
370                                                 $class = get_reg_class($reg);
371                                                 if (!defined $class) {
372                                                         die("Could not get ".uc($inout)." register class for '$op' pos $idx (reg $reg) ... exiting.\n");
373                                                 }
374                                                 else {
375                                                         last GET_CLASS;
376                                                 } # !defined class
377                                         } # if (reg =~ ...
378                                 } # foreach
379                         } # if
380
381                         push(@idx_class, $class);
382                 } # for
383         } # if
384
385         return @idx_class;
386 }
387
388 ###
389 # Generates the requirements for the given description
390 ###
391 sub generate_requirements {
392         my $n     = shift;
393         my $op    = shift;
394         my $inout = shift;
395
396         # get classes for the complementary direction
397         my $outin     = ($inout eq "in") ? "out" : "in";
398
399         my @reqs = @{ $n->{"reg_req"}{"$inout"} };
400
401         for (my $idx = 0; $idx <= $#reqs; $idx++) {
402                 my $class = undef;
403
404                 my $tmp2 = "const $arch\_register_req_t _".$op."_reg_req_$inout\_$idx = ";
405                 my $tmp  = "#define ".$op."_reg_req_$inout\_$idx ";
406
407                 if ($reqs[$idx] eq "none") {
408                         $tmp .= "&$arch\_default_req_none\n";
409                 }
410                 elsif ($reqs[$idx] =~ /^new_reg_(.*)$/) {
411                         if (is_reg_class($1)) {
412                                 $tmp  .=  "&_".$op."_reg_req_$inout\_$idx\n";
413                                 $tmp2 .= "{\n";
414                                 $tmp2 .= "  {\n";
415                                 $tmp2 .= "    arch_register_req_type_should_be_different_from_all,\n";
416                                 $tmp2 .= "    &$arch\_reg_classes[CLASS_$arch\_".$1."],\n";
417                                 $tmp2 .= "    NULL,        /* limit function */\n";
418                                 $tmp2 .= "    NULL,        /* limit environment */\n";
419                                 $tmp2 .= "    NULL,        /* same node */\n";
420                                 $tmp2 .= "    NULL         /* different node */\n";
421                                 $tmp2 .= "  },\n";
422                                 $tmp2 .= "  0,\n";
423                                 $tmp2 .= "  0\n";
424                                 $tmp2 .= "};\n";
425
426                                 push(@obst_req, $tmp2."\n");
427                                 push(@obst_header_all, "extern const $arch\_register_req_t _".$op."_reg_req_$inout\_$idx;\n");
428                         }
429                         else {
430                                 print STDERR "Invalid register class '$1' given in OUT requirement $idx for '$op'.\n";
431                         }
432                 }
433                 elsif (is_reg_class($reqs[$idx])) {
434                         $tmp .= "&$arch\_default_req_".$arch."_".$reqs[$idx]."\n";
435                 }
436                 else {
437                         my @req_type_mask;
438                         my ($class, $has_limit, $same_pos, $different_pos) = build_subset_class_func($n, $op, $idx, (($inout eq "in") ? 1 : 0), $reqs[$idx]);
439
440                         if (!defined($class)) {
441                                 die("Could not build subset for ".uc($inout)." requirements '$op' pos $idx ... exiting.\n");
442                         }
443
444                         if ($has_limit) {
445                                 push(@req_type_mask, "arch_register_req_type_limited");
446                         }
447                         if (defined($same_pos)) {
448                                 push(@req_type_mask, "arch_register_req_type_should_be_same");
449                         }
450                         if (defined($different_pos)) {
451                                 if ($different_pos == 666) {
452                                         push(@req_type_mask, "arch_register_req_type_should_be_different_from_all");
453                                         undef $different_pos;
454                                 }
455                                 else {
456                                         push(@req_type_mask, "arch_register_req_type_should_be_different");
457                                 }
458                         }
459
460                         $tmp  .= "&_".$op."_reg_req_$inout\_$idx\n";
461                         $tmp2 .= "{\n";
462                         $tmp2 .= "  {\n";
463                         $tmp2 .= "    ".join(" | ", @req_type_mask).",\n";
464                         $tmp2 .= "    &$arch\_reg_classes[CLASS_$arch\_".$class."],\n";
465                         $tmp2 .= "    ".($has_limit ? "limit_reg_".$op."_$inout\_".$idx : "NULL").",\n";
466                         $tmp2 .= "    NULL,        /* limit environment */\n";
467                         $tmp2 .= "    NULL,        /* same node */\n";
468                         $tmp2 .= "    NULL         /* different node */\n";
469                         $tmp2 .= "  },\n";
470                         $tmp2 .= "  ".(defined($same_pos) ? $same_pos : "0").",\n";
471                         $tmp2 .= "  ".(defined($different_pos) ? $different_pos : "0")."\n";
472                         $tmp2 .= "};\n";
473
474                         push(@obst_req, $tmp2."\n");
475                         push(@obst_header_all, "extern const $arch\_register_req_t _".$op."_reg_req_$inout\_$idx;\n");
476                 }
477
478                 push(@obst_requirement_def, $tmp);
479         }
480
481 }
482
483 ###
484 # Determines whether $name is a specified register class or not.
485 # @return 1 if name is register class, 0 otherwise
486 ###
487 sub is_reg_class {
488         my $name = shift;
489         return 1 if exists($reg_classes{"$name"});
490         return 0;
491 }
492
493 ###
494 # Returns the register class for a given register.
495 # @return class or undef
496 ###
497 sub get_reg_class {
498         my $reg = shift;
499         $reg = substr($reg, 1) if ($reg =~ /!.*/);
500         return $reg2class{"$reg"}{"class"} if (exists($reg2class{"$reg"}));
501         return undef;
502 }
503
504 ###
505 # Returns the index of a given register within it's register class.
506 # @return index or undef
507 ###
508 sub get_reg_index {
509         my $reg = shift;
510         return $reg2class{"$reg"}{"index"} if (exists($reg2class{"$reg"}));
511         return undef;
512 }
513
514 ###
515 # Generates the function for a given $op and a given IN-index
516 # which returns a subset of possible register from a register class
517 # @return classname from which the subset is derived or undef and
518 #         pos which corresponds to in/out reference position or undef
519 ###
520 sub build_subset_class_func {
521         my $neg           = undef;
522         my $class         = undef;
523         my $has_limit     = 0;
524         my $same_pos      = undef;
525         my $different_pos = undef;
526         my $temp;
527         my @obst_init;
528         my @obst_limits;
529         my @obst_ignore;
530
531
532         # build function header
533         my $n   = shift;
534         my $op  = shift;
535         my $idx = shift;
536         my $in  = shift;
537
538         my $outin = $in ? "out" : "in";
539         my @regs  = split(/ /, shift);
540
541         my @idx_class = build_inout_idx_class($n, $op, $outin);
542
543         # set/unset registers
544 CHECK_REQS: foreach (@regs) {
545                 if (/(!)?$outin\_r(\d+)/) {
546                         if (($1 && defined($different_pos)) || (!$1 && defined($same_pos))) {
547                                 print STDERR "Multiple in/out references of same type in one requirement not allowed.\n";
548                                 return (undef, undef, undef, undef);
549                         }
550
551                         if ($1) {
552                                 $different_pos = $in ? -$2 : $2 - 1;
553                         }
554                         else {
555                                 $same_pos = $in ? -$2 : $2 - 1;
556                         }
557
558                         $class = $idx_class[$2 - 1];
559                         next CHECK_REQS;
560                 }
561                 elsif (/!in/) {
562                         $class = $idx_class[0];
563                         return ($class, 0, undef, 666);
564                 }
565
566                 # check for negate
567                 if (substr($_, 0, 1) eq "!") {
568                         if (defined($neg) && $neg == 0) {
569                                 # we have seen a positiv constraint as first one but this one is negative
570                                 # this doesn't make sense
571                                 print STDERR "Mixed positive and negative constraints for the same slot are not allowed.\n";
572                                 return (undef, undef, undef, undef);
573                         }
574
575                         if (!defined($neg)) {
576                                 $has_limit = 1;
577                                 push(@obst_init, "  bs = bitset_set_all(bs);     /* allow all register (negative constraints given) */\n");
578                         }
579
580                         $_   = substr($_, 1); # skip '!'
581                         $neg = 1;
582                 }
583                 else {
584                         if (defined($neg) && $neg == 1) {
585                                 # we have seen a negative constraint as first one but this one is positive
586                                 # this doesn't make sense
587                                 print STDERR "Mixed positive and negative constraints for the same slot are not allowed.\n";
588                                 return (undef, undef, undef, undef);
589                         }
590
591                         if (!defined($neg)) {
592                                 $has_limit = 1;
593                                 push(@obst_init, "  bs = bitset_clear_all(bs);   /* disallow all register (positive constraints given) */\n");
594                         }
595                         $neg = 0;
596                 }
597
598                 # check if register belongs to one of the given classes
599                 $temp = get_reg_class($_);
600                 if (!defined($temp)) {
601                         print STDERR "Unknown register '$_'!\n";
602                         return (undef, undef, undef, undef);
603                 }
604
605                 # set class
606                 if (!defined($class)) {
607                         $class = $temp;
608                 }
609                 elsif ($class ne $temp) {
610                         # all registers must belong to the same class
611                         print STDERR "Registerclass mismatch. '$_' is not member of class '$class'.\n";
612                         return (undef, undef, undef, undef);
613                 }
614
615                 if ($neg == 1) {
616                         $has_limit = 1;
617                         push(@obst_limits, "  bitset_clear(bs, ".get_reg_index($_).");         /* disallow $_ */\n");
618                 }
619                 else {
620                         $has_limit = 1;
621                         push(@obst_limits, "  bitset_set(bs, ".get_reg_index($_).");           /* allow $_ */\n");
622                 }
623         }
624
625         my @cur_class = @{ $reg_classes{"$class"} };
626         for (my $idx = 0; $idx <= $#cur_class; $idx++) {
627                 if (defined($cur_class[$idx]{"type"}) && ($cur_class[$idx]{"type"} & 4)) {
628                         push(@obst_ignore, "  bitset_clear(bs, ".get_reg_index($cur_class[$idx]{"name"}).");");
629                         push(@obst_ignore, "         /* disallow ignore reg ".$cur_class[$idx]{"name"}." */\n");
630                 }
631         }
632
633         if ($has_limit == 1) {
634                 push(@obst_header_all, "void limit_reg_".$op."_".($in ? "in" : "out")."_".$idx."(void *_unused, bitset_t *bs);\n");
635
636                 push(@obst_limit_func, "/* limit the possible registers for ".($in ? "IN" : "OUT")." $idx at op $op */\n");
637                 push(@obst_limit_func, "void limit_reg_".$op."_".($in ? "in" : "out")."_".$idx."(void *_unused, bitset_t *bs) {\n");
638                 push(@obst_limit_func, @obst_init);
639                 push(@obst_limit_func, @obst_ignore);
640                 push(@obst_limit_func, @obst_limits);
641                 push(@obst_limit_func, "}\n\n");
642         }
643
644         return ($class, $has_limit, $same_pos, $different_pos);
645 }
646
647 ###
648 # Gets the variable name for the execution unit assigned to this register.
649 ###
650 sub get_execunit_variable_name {
651         my $unit    = shift;
652         my $name    = "NULL";
653         my $uc_arch = uc($arch);
654
655         if ($unit) {
656                 my $found = 0;
657 SRCH:   foreach my $cur_type (keys(%cpu)) {
658                         foreach my $cur_unit (@{ $cpu{"$cur_type"} }) {
659                                 if ($unit eq $cur_unit) {
660                                         my $tp_name   = "$arch\_execution_units_$cur_type";
661                                         my $unit_name = "$uc_arch\_EXECUNIT_TP_$cur_type\_$unit";
662                                         $name  = "&".$tp_name."[".$unit_name."]";
663                                         $found = 1;
664                                         last SRCH;
665                                 }
666                         }
667                 }
668
669                 if (! $found) {
670                         print STDERR "Invalid execution unit $unit specified!\n";
671                 }
672         }
673
674         return $name;
675 }