scripts: Use a string instead of magic numbers for register types.
[libfirm] / ir / be / scripts / generate_regalloc_if.pl
index 9201745..bfc88ff 100755 (executable)
 #!/usr/bin/perl -w
 
-# This script generates C code which emits assembler code for the
-# assembler ir nodes. It takes a "emit" key from the node specification
-# and substitutes lines starting with . with a corresponding fprintf().
+#
+# Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
+#
+# This file is part of libFirm.
+#
+# This file may be distributed and/or modified under the terms of the
+# GNU General Public License version 2 as published by the Free Software
+# Foundation and appearing in the file LICENSE.GPL included in the
+# packaging of this file.
+#
+# Licensees holding valid libFirm Professional Edition licenses may use
+# this file in accordance with the libFirm Commercial License.
+# Agreement provided with the Software.
+#
+# This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+# WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+# PURPOSE.
+#
+
+# This script generates C code which creates ands sets up functions and
+# data structures for the register allocator.
 # Creation: 2005/11/14
-# $Id$
 
 use strict;
 use Data::Dumper;
+use integer;
 
 my $specfile   = $ARGV[0];
 my $target_dir = $ARGV[1];
 
 our $arch;
 our %reg_classes;
-our %nodes;
+our %cpu;
 
 # include spec file
 
 my $return;
 
-no strict "subs";
+use strict "subs";
 unless ($return = do $specfile) {
-       warn "couldn't parse $specfile: $@" if $@;
-       warn "couldn't do $specfile: $!"    unless defined $return;
-       warn "couldn't run $specfile"       unless $return;
+       die "Fatal error: couldn't parse $specfile: $@" if $@;
+       die "Fatal error: couldn't do $specfile: $!"    unless defined $return;
+       die "Fatal error: couldn't run $specfile"       unless $return;
 }
 use strict "subs";
 
 my $target_c   = $target_dir."/gen_".$arch."_regalloc_if.c";
 my $target_h   = $target_dir."/gen_".$arch."_regalloc_if.h";
-my $target_h_t = $target_dir."/gen_".$arch."_regalloc_if_t.h";
 
 # helper function
-sub translate_reg_type {
-       my $t = shift;
-
-       if ($t == 0) {
-               return "arch_register_type_none";
-       }
-       else {
-               my @types;
-
-               if ($t & 1) {
-                       push(@types, "arch_register_type_caller_save");
-               }
-
-               if ($t & 2) {
-                       push(@types, "arch_register_type_callee_save");
-               }
-
-               if ($t & 4) {
-                       push(@types, "arch_register_type_ignore");
-               }
-
-               if ($t & 8) {
-                       push(@types, "arch_register_type_joker");
-               }
-
-               return join(" | ", @types);
-       }
+sub map_flags {
+       my $prefix = shift;
+       my $flags  = shift || "none";
+       return join(" | ", map { "$prefix$_" } split(/\s*\|\s*/, $flags));
 }
 
 # stacks for output
-my @obst_regtypes_def; # stack for the register type variables definitions
-my @obst_regtypes_decl;# stack for the register type variables declarations
-my @obst_regclasses;   # stack for the register class variables
-my @obst_classdef;     # stack to define a name for a class index
-my @obst_regdef;       # stack to define a name for a register index
-my @obst_reginit;      # stack for the register type inits
-my @obst_req;          # stack for the register requirements
-my @obst_limit_func;   # stack for functions to return a subset of a register class
-my @obst_defreq_head;  # stack for prototypes of default requirement function
-my @obst_header_all;   # stack for some extern struct defs needed for bearch_$arch include
-my @obst_requirement_def;  # stack for requirement name defines
-
-my $numregs;
+my $regtypes_def; # stack for the register type variables definitions
+my $regtypes_decl;# stack for the register type variables declarations
+my @regclasses;   # stack for the register class variables
+my $classdef;     # stack to define a name for a class index
+my $regdef;       # stack to define a name for a register index
+my $regdef2;
+my $regcounts;
+my $reginit;      # stack for the register type inits
+my $single_constraints_decls;
+my $single_constraints;
+
 my $class_ptr;
 my $class_idx = 0;
 
-my $tmp;
-
-my %reg2class;
-
-# there is a default NONE requirement
-$tmp = "/* Default NONE register requirements */\n";
-$tmp .= "const $arch\_register_req_t $arch\_default_req_none = {\n";
-$tmp .= "  {\n";
-$tmp .= "    arch_register_req_type_none,  /* register type  */\n";
-$tmp .= "    NULL,                         /* register class */\n";
-$tmp .= "    NULL,                         /* limit function */\n";
-$tmp .= "    NULL,                         /* limit environment */\n";
-$tmp .= "    NULL,                         /* node for same */\n";
-$tmp .= "    NULL                          /* node for different */\n";
-$tmp .= "  },\n";
-$tmp .= "  0,                              /* same pos */\n";
-$tmp .= "  0                               /* different pos */\n";
-$tmp .= "};\n\n";
-push(@obst_req, $tmp);
-push(@obst_header_all, "extern const $arch\_register_req_t $arch\_default_req_none;\n");
-
-push(@obst_classdef, "enum reg_classes {\n");
+my %regclass2len = ();
+my %reg2class = ();
+
+$classdef .= "enum reg_classes {\n";
 
 my $class_mode;
 
-# generate register type and class variable, init function and default requirements
 foreach my $class_name (keys(%reg_classes)) {
-       my @class         = @{ $reg_classes{"$class_name"} };
-       my $old_classname = $class_name;
-
-       $class_name = $arch."_".$class_name;
-       $numregs    = "N_".$class_name."_REGS";
-       $class_ptr  = "&".$arch."_reg_classes[CLASS_".$class_name."]";
-       $class_mode = pop(@class)->{"mode"};
-
-       push(@obst_regtypes_decl, "extern arch_register_t ".$class_name."_regs[$numregs];\n");
-       push(@obst_regtypes_def, "arch_register_t ".$class_name."_regs[$numregs];\n");
-
-       push(@obst_classdef, "  CLASS_$class_name = $class_idx,\n");
-       push(@obst_regclasses, "{ \"$class_name\", $numregs, NULL, ".$class_name."_regs }");
-
-       # there is a default NORMAL requirement for each class
-       $tmp  = "/* Default NORMAL register requirements for class $class_name */\n";
-       $tmp .= "const $arch\_register_req_t $arch\_default_req_$class_name = {\n";
-       $tmp .= "  {\n";
-       $tmp .= "    arch_register_req_type_normal,\n";
-       $tmp .= "    $class_ptr,\n";
-       $tmp .= "    NULL,                    /* limit function */ \n";
-       $tmp .= "    NULL,                    /* limit environment */\n";
-       $tmp .= "    NULL,                    /* node for same */\n";
-       $tmp .= "    NULL                     /* node for different */\n";
-       $tmp .= "  },\n";
-       $tmp .= "  0,                         /* same pos */\n";
-       $tmp .= "  0                          /* different pos */\n";
-       $tmp .= "};\n\n";
-       push(@obst_req, $tmp);
-       push(@obst_header_all, "extern const $arch\_register_req_t $arch\_default_req_$class_name;\n");
+       my @class = @{ $reg_classes{"$class_name"} };
 
        my $idx = 0;
-       push(@obst_reginit, "  /* Init of all registers in class '$class_name' */\n\n");
-       push(@obst_reginit, "  /* set largest possible mode for '$class_name' */\n");
-       push(@obst_reginit, "  $arch\_reg_classes[CLASS_".$class_name."].mode = $class_mode;\n\n");
-       push(@obst_regdef, "enum reg_".$class_name."_values {\n");
        foreach (@class) {
-               # For each class we build for each of it's member registers a limit function
-               # which limits the class to this particular register. We also build the
-               # corresponding requirement structs.
-               # We need those functions to set register requirements on demand in transformation
-               # esp. for Call and RegParams where we can mix int and float parameters.
-
-               my $limit_func_name = $arch."_limit_".$class_name."_".$_->{"name"};
-
-               # push the function prototype
-               $tmp = "void $limit_func_name(void *_unused, bitset_t *bs)";
-               push(@obst_defreq_head, $tmp.";\n");
-
-               # push the function definition
-               $tmp .= " {\n";
-               $tmp .= "    bs = bitset_clear_all(bs);\n";
-               $tmp .= "    bitset_set(bs, REG_".uc($_->{"name"}).");\n";  # REGISTER to index assignment is done some lines down
-               $tmp .= "}\n\n";
-               push(@obst_limit_func, $tmp);
-
-               # push the default requirement struct
-               $tmp  = "const $arch\_register_req_t $arch\_default_req_$class_name\_".$_->{"name"}." = {\n";
-               $tmp .= "  {\n";
-               $tmp .= "    arch_register_req_type_limited,\n";
-               $tmp .= "    $class_ptr,\n";
-               $tmp .= "    $limit_func_name,\n";
-               $tmp .= "    NULL,                     /* limit environment */\n";
-               $tmp .= "    NULL,                     /* node for same */\n";
-               $tmp .= "    NULL                      /* node for different */\n";
-               $tmp .= "  },\n";
-               $tmp .= "  0,                          /* same pos */\n";
-               $tmp .= "  0                           /* different pos */\n";
-               $tmp .= "};\n\n";
-               push(@obst_req, $tmp);
-               push(@obst_header_all,"extern const $arch\_register_req_t $arch\_default_req_$class_name\_".$_->{"name"}.";\n");
-
-               $reg2class{$_->{"name"}} = { "class" => $old_classname, "index" => $idx }; # remember reg to class for later use
-               push(@obst_regdef, "  REG_".uc($_->{"name"})." = $idx,\n");
-               push(@obst_reginit, "  ".$class_name."_regs[$idx].name      = \"".$_->{"name"}."\";\n");
-               push(@obst_reginit, "  ".$class_name."_regs[$idx].reg_class = $class_ptr;\n");
-               push(@obst_reginit, "  ".$class_name."_regs[$idx].index     = $idx;\n");
-               push(@obst_reginit, "  ".$class_name."_regs[$idx].type      = ".translate_reg_type($_->{"type"}).";\n");
-               push(@obst_reginit, "\n");
+               if (defined($_->{name})) {
+                       $reg2class{$_->{name}} = {
+                               "class" => $class_name,
+                               "index" => $idx
+                       };
+               }
                $idx++;
        }
-       push(@obst_regdef, "  $numregs = $idx\n");
-       push(@obst_regdef, "};\n\n");
-
-       $class_idx++;
+       $regclass2len{$class_name} = $idx;
 }
 
-push(@obst_classdef, "  N_CLASSES = ".scalar(keys(%reg_classes))."\n");
-push(@obst_classdef, "};\n\n");
-
-# generate node-register constraints
-foreach my $op (keys(%nodes)) {
-       my %n = %{ $nodes{"$op"} };
-
-       next if (!exists($n{"reg_req"}));
-
-       $op = $arch."_".$op;
-
-       push(@obst_req, "/* IN requirements for '$op' */\n");
-       # check for argument requirements
-       if (exists($n{"reg_req"}{"in"})) {
-               generate_requirements(\%n, $op, "in");
-       }
+sub get_limited_array {
+       my $reg      = shift;
+       my $regclass = $reg2class{"$reg"}{"class"};
+       my $ucname   = uc($reg);
+       my $result   = "{ ";
+
+       my $limitedbitsetlen = $regclass2len{$regclass};
+       my $arraylen         = ($limitedbitsetlen+31) / 32;
+       my $firstreg         = uc($reg_classes{$regclass}[0]->{"name"});
+       my $classuc          = uc($regclass);
+       my $first            = 1;
+       for (my $i = 0; $i < $arraylen; ++$i) {
+               if ($first) {
+                       $first = 0;
+               } else {
+                       $result .= ", ";
+               }
 
-       push(@obst_req, "/* OUT requirements for '$op' */\n");
-       # check for result requirements
-       if (exists($n{"reg_req"}{"out"})) {
-               generate_requirements(\%n, $op, "out");
+               my $index = $reg2class{"$reg"}{"index"};
+               if ($index >= $i*32 && $index < ($i+1)*32) {
+                       if ($i > 0) {
+                               $result .= "(1 << (REG_${classuc}_${ucname} % 32))";
+                       } else {
+                               $result .= "(1 << REG_${classuc}_${ucname})";
+                       }
+               } else {
+                       $result .= "0";
+               }
        }
+       $result .= " }";
 }
 
+# generate register type and class variable, init function and default requirements
+foreach my $class_name (keys(%reg_classes)) {
+       my @class         = @{ $reg_classes{"$class_name"} };
+       my $old_classname = $class_name;
 
+       $class_name = $arch."_".$class_name;
+       $class_ptr  = "&".$arch."_reg_classes[CLASS_".$class_name."]";
+       my $flags = pop(@class);
+       $class_mode  = $flags->{"mode"};
+       my $flags_prepared = map_flags("arch_register_class_flag_", $flags->{"flags"});
+
+       $single_constraints .= <<EOF;
+static const arch_register_req_t ${arch}_class_reg_req_${old_classname} = {
+       arch_register_req_type_normal,
+       &${arch}_reg_classes[CLASS_${arch}_${old_classname}],
+       NULL,
+       0,
+       0,
+       1
+};
+EOF
 
-# generate header _t (internal usage) file
-open(OUT, ">$target_h_t") || die("Could not open $target_h_t, reason: $!\n");
-
-my $creation_time = localtime(time());
-
-$tmp = uc($arch);
+       $classdef .= "\tCLASS_$class_name = $class_idx,\n";
+       my $numregs = @class;
+       my $first_reg = "&${arch}_registers[REG_". uc($class[0]->{"name"}) . "]";
+       push(@regclasses, "{ $class_idx, \"$class_name\", $numregs, NULL, $first_reg, $flags_prepared, &${arch}_class_reg_req_${old_classname} }");
 
-print OUT<<EOF;
-#ifndef _GEN_$tmp\_REGALLOC_IF_T_H_
-#define _GEN_$tmp\_REGALLOC_IF_T_H_
+       my $idx = 0;
+       $reginit .= "\t$arch\_reg_classes[CLASS_".$class_name."].mode = $class_mode;\n";
+       my $lastreg;
+       foreach (@class) {
+               my $name   = $_->{"name"};
+               my $ucname = uc($name);
+               my $type   = map_flags("arch_register_type_", $_->{"type"});
+               # realname is name if not set by user
+               $_->{"realname"} = $_->{"name"} if (! exists($_->{"realname"}));
+               my $realname = $_->{realname};
+               my $classuc = uc($old_classname);
+
+               $regdef  .= "\tREG_${ucname},\n";
+               $regdef2 .= "\tREG_${classuc}_${ucname} = $idx,\n";
+               my $dwarf_number = 0;
+               if (defined($_->{dwarf})) {
+                       $dwarf_number = $_->{dwarf};
+               }
 
-/**
- * Generated register classes from spec.
- *
- * DO NOT EDIT THIS FILE, your changes will be lost.
- * Edit $specfile instead.
- * created by: $0 $specfile $target_dir
- * date:       $creation_time
- */
+               $regtypes_def .= <<EOF;
+       {
+               "${realname}",
+               ${class_ptr},
+               REG_${classuc}_${ucname},
+               REG_${ucname},
+               ${type},
+               &${arch}_single_reg_req_${old_classname}_${name},
+               ${dwarf_number}
+       },
+EOF
 
+               my $limitedarray = get_limited_array($name);
+               $single_constraints .= <<EOF;
+static const unsigned ${arch}_limited_${old_classname}_${name} [] = ${limitedarray};
+static const arch_register_req_t ${arch}_single_reg_req_${old_classname}_${name} = {
+       arch_register_req_type_limited,
+       ${class_ptr},
+       ${arch}_limited_${old_classname}_${name},
+       0,
+       0,
+       1
+};
 EOF
 
-print OUT @obst_requirement_def;
+               $lastreg = $ucname;
+               $idx++;
+       }
+       $regcounts .= "\tN_${class_name}_REGS = $numregs,\n";
 
-print OUT "\n#endif /* _GEN_$tmp\_REGALLOC_IF_T_H_ */\n";
+       $class_idx++;
+}
 
+my $archuc = uc($arch);
 
+$classdef .= "\tN_${archuc}_CLASSES = ".scalar(keys(%reg_classes))."\n";
+$classdef .= "};\n\n";
 
 # generate header (external usage) file
-open(OUT, ">$target_h") || die("Could not open $target_h, reason: $!\n");
+open(OUT, ">$target_h") || die("Fatal error: Could not open $target_h, reason: $!\n");
 
-$creation_time = localtime(time());
+my $creation_time = localtime(time());
 
 print OUT<<EOF;
-#ifndef _GEN_$tmp\_REGALLOC_IF_H_
-#define _GEN_$tmp\_REGALLOC_IF_H_
-
 /**
- * Contains additional external requirements defs for external includes.
- *
- * DO NOT EDIT THIS FILE, your changes will be lost.
- * Edit $specfile instead.
- * created by: $0 $specfile $target_dir
- * date:       $creation_time
+ * \@file
+ * \@brief Contains additional external requirements defs for external includes.
+ * \@note   DO NOT EDIT THIS FILE, your changes will be lost.
+ *         Edit $specfile instead.
+ *         created by: $0 $specfile $target_dir
+ * \@date   $creation_time
  */
+#ifndef FIRM_BE_${archuc}_GEN_${archuc}_REGALLOC_IF_H
+#define FIRM_BE_${archuc}_GEN_${archuc}_REGALLOC_IF_H
 
-#include "../bearch.h"
-#include "$arch\_nodes_attr.h"
-
-EOF
-
-print OUT @obst_regdef, "\n";
-
-print OUT @obst_classdef, "\n";
-
-print OUT @obst_regtypes_decl, "\n";
+#include "bearch.h"
+#include "${arch}_nodes_attr.h"
 
-print OUT "extern arch_register_class_t $arch\_reg_classes[N_CLASSES];\n\n";
+/** global register indices for ${arch} registers */
+enum reg_indices {
+${regdef}
+       N_${archuc}_REGISTERS
+};
+/** local register indices for ${arch} registers */
+enum {
+${regdef2}
+};
 
-print OUT "void ".$arch."_register_init(void *isa_ptr);\n\n";
+/** number of registers in ${arch} register classes. */
+enum {
+${regcounts}
+};
+${classdef}
 
-print OUT @obst_header_all, "\n";
+extern const arch_register_t ${arch}_registers[N_${archuc}_REGISTERS];
 
-print OUT @obst_defreq_head, "\n";
+extern arch_register_class_t ${arch}_reg_classes[N_${archuc}_CLASSES];
 
-print OUT "\n#endif /* _GEN_$tmp\_REGALLOC_IF_H_ */\n";
+void ${arch}_register_init(void);
 
+#endif
+EOF
 close(OUT);
 
 
-
-# generate c inline file
-open(OUT, ">$target_c") || die("Could not open $target_c, reason: $!\n");
+# generate c file
+open(OUT, ">$target_c") || die("Fatal error: Could not open $target_c, reason: $!\n");
 
 $creation_time = localtime(time());
 
 print OUT<<EOF;
 /**
- * The generated interface for the register allocator.
- * Contains register classes and types and register constraints
- * for all nodes where constraints were given in spec.
- *
- * DO NOT EDIT THIS FILE, your changes will be lost.
- * Edit $specfile instead.
- * created by: $0 $specfile $target_dir
- * date:       $creation_time
+ * \@file
+ * \@brief  The generated interface for the register allocator.
+ *          Contains register classes and types and register constraints
+ *          for all nodes where constraints were given in spec.
+ * \@note    DO NOT EDIT THIS FILE, your changes will be lost.
+ *          Edit $specfile instead.
+ *          created by: $0 $specfile $target_dir
+ * \$date    $creation_time
  */
+#include "config.h"
 
-#include "gen_$arch\_regalloc_if.h"
-#include "bearch_$arch\_t.h"   /* we need this to put the caller saved registers into the isa set */
-#include "$arch\_map_regs.h"
+#include "gen_${arch}_regalloc_if.h"
+#include "bearch_${arch}_t.h"
 #include "irmode.h"
 
+${single_constraints}
 EOF
 
-print OUT "arch_register_class_t $arch\_reg_classes[] = {\n  ".join(",\n  ", @obst_regclasses)."\n};\n\n";
-
-print OUT @obst_regtypes_def, "\n";
-
-print OUT "void ".$arch."_register_init(void *isa_ptr) {\n";
-print OUT @obst_reginit;
-print OUT "}\n\n";
-
-print OUT @obst_limit_func;
-
-print OUT @obst_req;
-
-close(OUT);
-
-###
-# Remember the register class for each index in the given requirements.
-# We need this information for requirements like "in_sX" or "out_dX"
-# @return array of classes corresponding to the requirement for each index
-###
-sub build_inout_idx_class {
-       my $n     = shift;
-       my $op    = shift;
-       my $inout = shift;
-       my @idx_class;
-
-       if (exists($n->{"reg_req"}{"$inout"})) {
-               my @reqs = @{ $n->{"reg_req"}{"$inout"} };
-
-               for (my $idx = 0; $idx <= $#reqs; $idx++) {
-                       my $class = undef;
-
-                       if ($reqs[$idx] eq "none") {
-                               $class = "none";
-                       }
-                       elsif (is_reg_class($reqs[$idx])) {
-                               $class = $reqs[$idx];
-                       }
-                       else {
-                               my @regs = split(/ /, $reqs[$idx]);
-GET_CLASS:             foreach my $reg (@regs) {
-                                       if ($reg =~ /!?(in|out)\_r\d+/ || $reg =~ /!in/) {
-                                               $class = "UNKNOWN_CLASS";
-                                       }
-                                       else {
-                                               $class = get_reg_class($reg);
-                                               if (!defined $class) {
-                                                       die("Could not get ".uc($inout)." register class for '$op' pos $idx (reg $reg) ... exiting.\n");
-                                               }
-                                               else {
-                                                       last GET_CLASS;
-                                               } # !defined class
-                                       } # if (reg =~ ...
-                               } # foreach
-                       } # if
-
-                       push(@idx_class, $class);
-               } # for
-       } # if
-
-       return @idx_class;
-}
-
-###
-# Generates the requirements for the given description
-###
-sub generate_requirements {
-       my $n     = shift;
-       my $op    = shift;
-       my $inout = shift;
-
-       # get classes for the complementary direction
-       my $outin     = ($inout eq "in") ? "out" : "in";
-
-       my @reqs = @{ $n->{"reg_req"}{"$inout"} };
-
-       for (my $idx = 0; $idx <= $#reqs; $idx++) {
-               my $class = undef;
-
-               my $tmp2 = "const $arch\_register_req_t _".$op."_reg_req_$inout\_$idx = ";
-               my $tmp  = "#define ".$op."_reg_req_$inout\_$idx ";
-
-               if ($reqs[$idx] eq "none") {
-                       $tmp .= "&$arch\_default_req_none\n";
-               }
-               elsif ($reqs[$idx] =~ /^new_reg_(.*)$/) {
-                       if (is_reg_class($1)) {
-                               $tmp  .=  "&_".$op."_reg_req_$inout\_$idx\n";
-                               $tmp2 .= "{\n";
-                               $tmp2 .= "  {\n";
-                               $tmp2 .= "    arch_register_req_type_should_be_different_from_all,\n";
-                               $tmp2 .= "    &$arch\_reg_classes[CLASS_$arch\_".$1."],\n";
-                               $tmp2 .= "    NULL,        /* limit function */\n";
-                               $tmp2 .= "    NULL,        /* limit environment */\n";
-                               $tmp2 .= "    NULL,        /* same node */\n";
-                               $tmp2 .= "    NULL         /* different node */\n";
-                               $tmp2 .= "  },\n";
-                               $tmp2 .= "  0,\n";
-                               $tmp2 .= "  0\n";
-                               $tmp2 .= "};\n";
-
-                               push(@obst_req, $tmp2."\n");
-                               push(@obst_header_all, "extern const $arch\_register_req_t _".$op."_reg_req_$inout\_$idx;\n");
-                       }
-                       else {
-                               print STDERR "Invalid register class '$1' given in OUT requirement $idx for '$op'.\n";
-                       }
-               }
-               elsif (is_reg_class($reqs[$idx])) {
-                       $tmp .= "&$arch\_default_req_".$arch."_".$reqs[$idx]."\n";
-               }
-               else {
-                       my @req_type_mask;
-                       my ($class, $has_limit, $same_pos, $different_pos) = build_subset_class_func($n, $op, $idx, (($inout eq "in") ? 1 : 0), $reqs[$idx]);
-
-                       if (!defined($class)) {
-                               die("Could not build subset for ".uc($inout)." requirements '$op' pos $idx ... exiting.\n");
-                       }
-
-                       if ($has_limit) {
-                               push(@req_type_mask, "arch_register_req_type_limited");
-                       }
-                       if (defined($same_pos)) {
-                               push(@req_type_mask, "arch_register_req_type_should_be_same");
-                       }
-                       if (defined($different_pos)) {
-                               if ($different_pos == 666) {
-                                       push(@req_type_mask, "arch_register_req_type_should_be_different_from_all");
-                                       undef $different_pos;
-                               }
-                               else {
-                                       push(@req_type_mask, "arch_register_req_type_should_be_different");
-                               }
-                       }
-
-                       $tmp  .= "&_".$op."_reg_req_$inout\_$idx\n";
-                       $tmp2 .= "{\n";
-                       $tmp2 .= "  {\n";
-                       $tmp2 .= "    ".join(" | ", @req_type_mask).",\n";
-                       $tmp2 .= "    &$arch\_reg_classes[CLASS_$arch\_".$class."],\n";
-                       $tmp2 .= "    ".($has_limit ? "limit_reg_".$op."_$inout\_".$idx : "NULL").",\n";
-                       $tmp2 .= "    NULL,        /* limit environment */\n";
-                       $tmp2 .= "    NULL,        /* same node */\n";
-                       $tmp2 .= "    NULL         /* different node */\n";
-                       $tmp2 .= "  },\n";
-                       $tmp2 .= "  ".(defined($same_pos) ? $same_pos : "0").",\n";
-                       $tmp2 .= "  ".(defined($different_pos) ? $different_pos : "0")."\n";
-                       $tmp2 .= "};\n";
-
-                       push(@obst_req, $tmp2."\n");
-                       push(@obst_header_all, "extern const $arch\_register_req_t _".$op."_reg_req_$inout\_$idx;\n");
-               }
-
-               push(@obst_requirement_def, $tmp);
-       }
-
-}
-
-###
-# Determines whether $name is a specified register class or not.
-# @return 1 if name is register class, 0 otherwise
-###
-sub is_reg_class {
-       my $name = shift;
-       return 1 if exists($reg_classes{"$name"});
-       return 0;
-}
-
-###
-# Returns the register class for a given register.
-# @return class or undef
-###
-sub get_reg_class {
-       my $reg = shift;
-       $reg = substr($reg, 1) if ($reg =~ /!.*/);
-       return $reg2class{"$reg"}{"class"} if (exists($reg2class{"$reg"}));
-       return undef;
-}
-
-###
-# Returns the index of a given register within it's register class.
-# @return index or undef
-###
-sub get_reg_index {
-       my $reg = shift;
-       return $reg2class{"$reg"}{"index"} if (exists($reg2class{"$reg"}));
-       return undef;
-}
-
-###
-# Generates the function for a given $op and a given IN-index
-# which returns a subset of possible register from a register class
-# @return classname from which the subset is derived or undef and
-#         pos which corresponds to in/out reference position or undef
-###
-sub build_subset_class_func {
-       my $neg           = undef;
-       my $class         = undef;
-       my $has_limit     = 0;
-       my $same_pos      = undef;
-       my $different_pos = undef;
-       my $temp;
-       my @obst_init;
-       my @obst_limits;
-       my @obst_ignore;
-
-
-       # build function header
-       my $n   = shift;
-       my $op  = shift;
-       my $idx = shift;
-       my $in  = shift;
-
-       my $outin = $in ? "out" : "in";
-       my @regs  = split(/ /, shift);
-
-       my @idx_class = build_inout_idx_class($n, $op, $outin);
-
-       # set/unset registers
-CHECK_REQS: foreach (@regs) {
-               if (/(!)?$outin\_r(\d+)/) {
-                       if (($1 && defined($different_pos)) || (!$1 && defined($same_pos))) {
-                               print STDERR "Multiple in/out references of same type in one requirement not allowed.\n";
-                               return (undef, undef, undef, undef);
-                       }
+print OUT "arch_register_class_t ${arch}_reg_classes[] = {\n\t".join(",\n\t", @regclasses)."\n};\n\n";
 
-                       if ($1) {
-                               $different_pos = $in ? -$2 : $2 - 1;
-                       }
-                       else {
-                               $same_pos = $in ? -$2 : $2 - 1;
-                       }
-
-                       $class = $idx_class[$2 - 1];
-                       next CHECK_REQS;
-               }
-               elsif (/!in/) {
-                       $class = $idx_class[0];
-                       return ($class, 0, undef, 666);
-               }
-
-               # check for negate
-               if (substr($_, 0, 1) eq "!") {
-                       if (defined($neg) && $neg == 0) {
-                               # we have seen a positiv constraint as first one but this one is negative
-                               # this doesn't make sense
-                               print STDERR "Mixed positive and negative constraints for the same slot are not allowed.\n";
-                               return (undef, undef, undef, undef);
-                       }
-
-                       if (!defined($neg)) {
-                               $has_limit = 1;
-                               push(@obst_init, "  bs = bitset_set_all(bs);     /* allow all register (negative constraints given) */\n");
-                       }
-
-                       $_   = substr($_, 1); # skip '!'
-                       $neg = 1;
-               }
-               else {
-                       if (defined($neg) && $neg == 1) {
-                               # we have seen a negative constraint as first one but this one is positive
-                               # this doesn't make sense
-                               print STDERR "Mixed positive and negative constraints for the same slot are not allowed.\n";
-                               return (undef, undef, undef, undef);
-                       }
-
-                       if (!defined($neg)) {
-                               $has_limit = 1;
-                               push(@obst_init, "  bs = bitset_clear_all(bs);   /* disallow all register (positive constraints given) */\n");
-                       }
-                       $neg = 0;
-               }
-
-               # check if register belongs to one of the given classes
-               $temp = get_reg_class($_);
-               if (!defined($temp)) {
-                       print STDERR "Unknown register '$_'!\n";
-                       return (undef, undef, undef, undef);
-               }
-
-               # set class
-               if (!defined($class)) {
-                       $class = $temp;
-               }
-               elsif ($class ne $temp) {
-                       # all registers must belong to the same class
-                       print STDERR "Registerclass mismatch. '$_' is not member of class '$class'.\n";
-                       return (undef, undef, undef, undef);
-               }
-
-               if ($neg == 1) {
-                       $has_limit = 1;
-                       push(@obst_limits, "  bitset_clear(bs, ".get_reg_index($_).");         /* disallow $_ */\n");
-               }
-               else {
-                       $has_limit = 1;
-                       push(@obst_limits, "  bitset_set(bs, ".get_reg_index($_).");           /* allow $_ */\n");
-               }
-       }
-
-       my @cur_class = @{ $reg_classes{"$class"} };
-       for (my $idx = 0; $idx <= $#cur_class; $idx++) {
-               if (defined($cur_class[$idx]{"type"}) && ($cur_class[$idx]{"type"} & 4)) {
-                       push(@obst_ignore, "  bitset_clear(bs, ".get_reg_index($cur_class[$idx]{"name"}).");");
-                       push(@obst_ignore, "         /* disallow ignore reg ".$cur_class[$idx]{"name"}." */\n");
-               }
-       }
-
-       if ($has_limit == 1) {
-               push(@obst_header_all, "void limit_reg_".$op."_".($in ? "in" : "out")."_".$idx."(void *_unused, bitset_t *bs);\n");
+print OUT<<EOF;
 
-               push(@obst_limit_func, "/* limit the possible registers for ".($in ? "IN" : "OUT")." $idx at op $op */\n");
-               push(@obst_limit_func, "void limit_reg_".$op."_".($in ? "in" : "out")."_".$idx."(void *_unused, bitset_t *bs) {\n");
-               push(@obst_limit_func, @obst_init);
-               push(@obst_limit_func, @obst_ignore);
-               push(@obst_limit_func, @obst_limits);
-               push(@obst_limit_func, "}\n\n");
-       }
+/** The array of all registers in the ${arch} architecture, sorted by its global index.*/
+const arch_register_t ${arch}_registers[] = {
+${regtypes_def}
+};
 
-       return ($class, $has_limit, $same_pos, $different_pos);
+/**
+ * Initializes ${arch} register classes.
+ */
+void ${arch}_register_init(void)
+{
+${reginit}
 }
+EOF
+close(OUT);