insns.pl

   1 #!/usr/bin/perl
   2 #
   3 # insns.pl   produce insnsa.c, insnsd.c, insnsi.h, insnsn.c from insns.dat
   4 #
   5 # The Netwide Assembler is copyright (C) 1996 Simon Tatham and
   6 # Julian Hall. All rights reserved. The software is
   7 # redistributable under the license given in the file "LICENSE"
   8 # distributed in the NASM archive.
   9
  10 # Opcode prefixes which need their own opcode tables
  11 # LONGER PREFIXES FIRST!
  12 @disasm_prefixes = qw(0F24 0F25 0F38 0F3A 0F7A 0FA6 0FA7 0F);
  13
  14 # This should match MAX_OPERANDS from nasm.h
  15 $MAX_OPERANDS = 5;
  16
  17 print STDERR "Reading insns.dat...\n";
  18
  19 @args   = ();
  20 undef $output;
  21 foreach $arg ( @ARGV ) {
  22     if ( $arg =~ /^\-/ ) {
  23         if  ( $arg =~ /^\-([abdin])$/ ) {
  24             $output = $1;
  25         } else {
  26             die "$0: Unknown option: ${arg}\n";
  27         }
  28     } else {
  29         push (@args, $arg);
  30     }
  31 }
  32
  33 $fname = "insns.dat" unless $fname = $args[0];
  34 open (F, $fname) || die "unable to open $fname";
  35
  36 %dinstables = ();
  37 @bytecode_list = ();
  38
  39 $line = 0;
  40 $insns = 0;
  41 while (<F>) {
  42   $line++;
  43   chomp;
  44   next if ( /^\s*(\;.*|)$/ );   # comments or blank lines
  45
  46   unless (/^\s*(\S+)\s+(\S+)\s+(\S+|\[.*\])\s+(\S+)\s*$/) {
  47       warn "line $line does not contain four fields\n";
  48       next;
  49   }
  50   @fields = ($1, $2, $3, $4);
  51   ($formatted, $nd) = format_insn(@fields);
  52   if ($formatted) {
  53     $insns++;
  54     $aname = "aa_$fields[0]";
  55     push @$aname, $formatted;
  56   }
  57   if ( $fields[0] =~ /cc$/ ) {
  58       # Conditional instruction
  59       $k_opcodes_cc{$fields[0]}++;
  60   } else {
  61       # Unconditional instruction
  62       $k_opcodes{$fields[0]}++;
  63   }
  64   if ($formatted && !$nd) {
  65     push @big, $formatted;
  66     my @sseq = startseq($fields[2]);
  67     foreach $i (@sseq) {
  68         if (!defined($dinstables{$i})) {
  69             $dinstables{$i} = [];
  70         }
  71         push(@{$dinstables{$i}}, $#big);
  72     }
  73   }
  74 }
  75
  76 close F;
  77
  78 #
  79 # Generate the bytecode array.  At this point, @bytecode_list contains
  80 # the full set of bytecodes.
  81 #
  82
  83 # Sort by descending length
  84 @bytecode_list = sort { scalar(@$b) <=> scalar(@$a) } @bytecode_list;
  85 @bytecode_array = ();
  86 %bytecode_pos = ();
  87 $bytecode_next = 0;
  88 foreach $bl (@bytecode_list) {
  89     my $h = hexstr(@$bl);
  90     next if (defined($bytecode_pos{$h}));
  91
  92     push(@bytecode_array, $bl);
  93     while ($h ne '') {
  94         $bytecode_pos{$h} = $bytecode_next;
  95         $h = substr($h, 2);
  96         $bytecode_next++;
  97     }
  98 }
  99 undef @bytecode_list;
 100
 101 @opcodes    = sort keys(%k_opcodes);
 102 @opcodes_cc = sort keys(%k_opcodes_cc);
 103
 104 if ( !defined($output) || $output eq 'b') {
 105     print STDERR "Writing insnsb.c...\n";
 106
 107     open B, ">insnsb.c";
 108
 109     print B "/* This file auto-generated from insns.dat by insns.pl" .
 110         " - don't edit it */\n\n";
 111
 112     print B "#include \"nasm.h\"\n";
 113     print B "#include \"insns.h\"\n\n";
 114
 115     print B "const uint8_t nasm_bytecodes[$bytecode_next] = {\n";
 116
 117     $p = 0;
 118     foreach $bl (@bytecode_array) {
 119         printf B "    /* %5d */ ", $p;
 120         foreach $d (@$bl) {
 121             printf B "%#o,", $d;
 122             $p++;
 123         }
 124         printf B "\n";
 125     }
 126     print B "};\n";
 127
 128     close B;
 129 }
 130
 131 if ( !defined($output) || $output eq 'a' ) {
 132     print STDERR "Writing insnsa.c...\n";
 133
 134     open A, ">insnsa.c";
 135
 136     print A "/* This file auto-generated from insns.dat by insns.pl" .
 137         " - don't edit it */\n\n";
 138
 139     print A "#include \"nasm.h\"\n";
 140     print A "#include \"insns.h\"\n\n";
 141
 142     foreach $i (@opcodes, @opcodes_cc) {
 143         print A "static const struct itemplate instrux_${i}[] = {\n";
 144         $aname = "aa_$i";
 145         foreach $j (@$aname) {
 146             print A "    ", codesubst($j), "\n";
 147         }
 148         print A "    ITEMPLATE_END\n};\n\n";
 149     }
 150     print A "const struct itemplate * const nasm_instructions[] = {\n";
 151     foreach $i (@opcodes, @opcodes_cc) {
 152         print A "    instrux_${i},\n";
 153     }
 154     print A "};\n";
 155
 156     close A;
 157 }
 158
 159 if ( !defined($output) || $output eq 'd' ) {
 160     print STDERR "Writing insnsd.c...\n";
 161
 162     open D, ">insnsd.c";
 163
 164     print D "/* This file auto-generated from insns.dat by insns.pl" .
 165         " - don't edit it */\n\n";
 166
 167     print D "#include \"nasm.h\"\n";
 168     print D "#include \"insns.h\"\n\n";
 169
 170     print D "static const struct itemplate instrux[] = {\n";
 171     $n = 0;
 172     foreach $j (@big) {
 173         printf D "    /* %4d */ %s\n", $n++, codesubst($j);
 174     }
 175     print D "};\n";
 176
 177     foreach $h (sort(keys(%dinstables))) {
 178         print D "\nstatic const struct itemplate * const itable_${h}[] = {\n";
 179         foreach $j (@{$dinstables{$h}}) {
 180             print D "    instrux + $j,\n";
 181         }
 182         print D "};\n";
 183     }
 184
 185     foreach $h (@disasm_prefixes, '') {
 186         $is_prefix{$h} = 1;
 187         print D "\n";
 188         print D "static " unless ($h eq '');
 189         print D "const struct disasm_index ";
 190         print D ($h eq '') ? 'itable' : "itable_$h";
 191         print D "[256] = {\n";
 192         for ($c = 0; $c < 256; $c++) {
 193             $nn = sprintf("%s%02X", $h, $c);
 194             if ($is_prefix{$nn}) {
 195                 die "$0: ambiguous decoding of $nn\n"
 196                     if (defined($dinstables{$nn}));
 197                 printf D "    { itable_%s, -1 },\n", $nn;
 198             } elsif (defined($dinstables{$nn})) {
 199                 printf D "    { itable_%s, %u },\n",
 200                 $nn, scalar(@{$dinstables{$nn}});
 201             } else {
 202                 printf D "    { NULL, 0 },\n";
 203             }
 204         }
 205     print D "};\n";
 206     }
 207
 208     close D;
 209 }
 210
 211 if ( !defined($output) || $output eq 'i' ) {
 212     print STDERR "Writing insnsi.h...\n";
 213
 214     open I, ">insnsi.h";
 215
 216     print I "/* This file is auto-generated from insns.dat by insns.pl" .
 217         " - don't edit it */\n\n";
 218     print I "/* This file in included by nasm.h */\n\n";
 219
 220     print I "/* Instruction names */\n\n";
 221     print I "#ifndef NASM_INSNSI_H\n";
 222     print I "#define NASM_INSNSI_H 1\n\n";
 223     print I "enum opcode {\n";
 224     $maxlen = 0;
 225     foreach $i (@opcodes, @opcodes_cc) {
 226         print I "\tI_${i},\n";
 227         $len = length($i);
 228         $len++ if ( $i =~ /cc$/ );      # Condition codes can be 3 characters long
 229         $maxlen = $len if ( $len > $maxlen );
 230     }
 231     print I "\tI_none = -1\n";
 232     print I "\n};\n\n";
 233     print I "#define MAX_INSLEN ", $maxlen, "\n\n";
 234     print I "#endif /* NASM_INSNSI_H */\n";
 235
 236     close I;
 237 }
 238
 239 if ( !defined($output) || $output eq 'n' ) {
 240     print STDERR "Writing insnsn.c...\n";
 241
 242     open N, ">insnsn.c";
 243
 244     print N "/* This file is auto-generated from insns.dat by insns.pl" .
 245         " - don't edit it */\n\n";
 246     print N "/* This file in included by names.c */\n\n";
 247
 248     print N "static const char * const insn_names[] = {";
 249     $first = 1;
 250     foreach $i (@opcodes) {
 251         print N "," if ( !$first );
 252         $first = 0;
 253         $ilower = $i;
 254         $ilower =~ tr/A-Z/a-z/; # Change to lower case (Perl 4 compatible)
 255         print N "\n\t\"${ilower}\"";
 256     }
 257     print N "\n};\n\n";
 258     print N "/* Conditional instructions */\n";
 259     print N "static const char *icn[] = {";
 260     $first = 1;
 261     foreach $i (@opcodes_cc) {
 262         print N "," if ( !$first );
 263         $first = 0;
 264         $ilower = $i;
 265         $ilower =~ s/cc$//;             # Skip cc suffix
 266         $ilower =~ tr/A-Z/a-z/; # Change to lower case (Perl 4 compatible)
 267         print N "\n\t\"${ilower}\"";
 268     }
 269
 270     print N "\n};\n\n";
 271     print N "/* and the corresponding opcodes */\n";
 272     print N "static const enum opcode ico[] = {";
 273     $first = 1;
 274     foreach $i (@opcodes_cc) {
 275         print N "," if ( !$first );
 276         $first = 0;
 277         print N "\n\tI_$i";
 278     }
 279
 280     print N "\n};\n";
 281
 282     close N;
 283 }
 284
 285 printf STDERR "Done: %d instructions\n", $insns;
 286
 287 sub format_insn(@) {
 288     my ($opcode, $operands, $codes, $flags) = @_;
 289     my $num, $nd = 0;
 290     my @bytecode;
 291
 292     return (undef, undef) if $operands eq "ignore";
 293
 294     # format the operands
 295     $operands =~ s/:/|colon,/g;
 296     $operands =~ s/mem(\d+)/mem|bits$1/g;
 297     $operands =~ s/mem/memory/g;
 298     $operands =~ s/memory_offs/mem_offs/g;
 299     $operands =~ s/imm(\d+)/imm|bits$1/g;
 300     $operands =~ s/imm/immediate/g;
 301     $operands =~ s/rm(\d+)/rm_gpr|bits$1/g;
 302     $operands =~ s/(mmx|xmm|ymm)rm/rm_$1/g;
 303     $operands =~ s/\=([0-9]+)/same_as|$1/g;
 304     if ($operands eq 'void') {
 305         @ops = ();
 306     } else {
 307         @ops = split(/\,/, $operands);
 308     }
 309     $num = scalar(@ops);
 310     while (scalar(@ops) < $MAX_OPERANDS) {
 311         push(@ops, '0');
 312     }
 313     $operands = join(',', @ops);
 314     $operands =~ tr/a-z/A-Z/;
 315
 316     # format the flags
 317     $flags =~ s/,/|IF_/g;
 318     $flags =~ s/(\|IF_ND|IF_ND\|)//, $nd = 1 if $flags =~ /IF_ND/;
 319     $flags = "IF_" . $flags;
 320
 321     @bytecode = (decodify($codes), 0);
 322     push(@bytecode_list, [@bytecode]);
 323     $codes = hexstr(@bytecode);
 324
 325     ("{I_$opcode, $num, {$operands}, \@\@CODES-$codes\@\@, $flags},", $nd);
 326 }
 327
 328 #
 329 # Look for @@CODES-xxx@@ sequences and replace them with the appropriate
 330 # offset into nasm_bytecodes
 331 #
 332 sub codesubst($) {
 333     my($s) = @_;
 334     my $n;
 335
 336     while ($s =~ /\@\@CODES-([0-9A-F]+)\@\@/) {
 337         my $pos = $bytecode_pos{$1};
 338         if (!defined($pos)) {
 339             die "$0: no position assigned to byte code $1\n";
 340         }
 341         $s = $` . "nasm_bytecodes+${pos}" . "$'";
 342     }
 343     return $s;
 344 }
 345
 346 sub addprefix ($@) {
 347     my ($prefix, @list) = @_;
 348     my $x;
 349     my @l = ();
 350
 351     foreach $x (@list) {
 352         push(@l, sprintf("%s%02X", $prefix, $x));
 353     }
 354
 355     return @l;
 356 }
 357
 358 #
 359 # Turn a code string into a sequence of bytes
 360 #
 361 sub decodify($) {
 362   # Although these are C-syntax strings, by convention they should have
 363   # only octal escapes (for directives) and hexadecimal escapes
 364   # (for verbatim bytes)
 365     my($codestr) = @_;
 366     my $c = $codestr;
 367     my @codes = ();
 368
 369     if ($codestr =~ /^\s*\[([^\]]*)\]\s*$/) {
 370         return byte_code_compile($1);
 371     }
 372
 373     while ($c ne '') {
 374         if ($c =~ /^\\x([0-9a-f]+)(.*)$/i) {
 375             push(@codes, hex $1);
 376             $c = $2;
 377             next;
 378         } elsif ($c =~ /^\\([0-7]{1,3})(.*)$/) {
 379             push(@codes, oct $1);
 380             $c = $2;
 381             next;
 382         } else {
 383             die "$0: unknown code format in \"$codestr\"\n";
 384         }
 385     }
 386
 387     return @codes;
 388 }
 389
 390 # Turn a numeric list into a hex string
 391 sub hexstr(@) {
 392     my $s = '';
 393     my $c;
 394
 395     foreach $c (@_) {
 396         $s .= sprintf("%02X", $c);
 397     }
 398     return $s;
 399 }
 400
 401 # Here we determine the range of possible starting bytes for a given
 402 # instruction. We need only consider the codes:
 403 # \1 \2 \3     mean literal bytes, of course
 404 # \4 \5 \6 \7  mean PUSH/POP of segment registers: special case
 405 # \1[0123]     mean byte plus register value
 406 # \330         means byte plus condition code
 407 # \0 or \340   mean give up and return empty set
 408 sub startseq($) {
 409   my ($codestr) = @_;
 410   my $word, @range;
 411   my @codes = ();
 412   my $c = $codestr;
 413   my $c0, $c1, $i;
 414   my $prefix = '';
 415
 416   @codes = decodify($codestr);
 417
 418   while ($c0 = shift(@codes)) {
 419       $c1 = $codes[0];
 420       if ($c0 == 01 || $c0 == 02 || $c0 == 03) {
 421           # Fixed byte string
 422           my $fbs = $prefix;
 423           while (1) {
 424               if ($c0 == 01 || $c0 == 02 || $c0 == 03) {
 425                   while ($c0--) {
 426                       $fbs .= sprintf("%02X", shift(@codes));
 427                   }
 428               } else {
 429                   last;
 430               }
 431               $c0 = shift(@codes);
 432           }
 433
 434           foreach $pfx (@disasm_prefixes) {
 435               if (substr($fbs, 0, length($pfx)) eq $pfx) {
 436                   $prefix = $pfx;
 437                   $fbs = substr($fbs, length($pfx));
 438                   last;
 439               }
 440           }
 441
 442           if ($fbs ne '') {
 443               return ($prefix.substr($fbs,0,2));
 444           }
 445
 446           unshift(@codes, $c0);
 447       } elsif ($c0 == 04) {
 448           return addprefix($prefix, 0x07, 0x17, 0x1F);
 449       } elsif ($c0 == 05) {
 450           return addprefix($prefix, 0xA1, 0xA9);
 451       } elsif ($c0 == 06) {
 452           return addprefix($prefix, 0x06, 0x0E, 0x16, 0x1E);
 453       } elsif ($c0 == 07) {
 454           return addprefix($prefix, 0xA0, 0xA8);
 455       } elsif ($c0 >= 010 && $c0 <= 013) {
 456           return addprefix($prefix, $c1..($c1+7));
 457       } elsif (($c0 & ~013) == 0144) {
 458           return addprefix($prefix, $c1, $c1|2);
 459       } elsif ($c0 == 0330) {
 460           return addprefix($prefix, $c1..($c1+15));
 461       } elsif ($c0 == 0 || $c0 == 0340) {
 462           return $prefix;
 463       } elsif (($c0 & ~3) == 0260 || $c0 == 270) {
 464           shift(@codes);
 465           shift(@codes);
 466       } elsif ($c0 == 0172) {
 467           shift(@codes);
 468       } else {
 469           # We really need to be able to distinguish "forbidden"
 470           # and "ignorable" codes here
 471       }
 472   }
 473   return $prefix;
 474 }
 475
 476 #
 477 # This function takes a series of byte codes in a format which is more
 478 # typical of the Intel documentation, and encode it.
 479 #
 480 # The format looks like:
 481 #
 482 # [operands: opcodes]
 483 #
 484 # The operands word lists the order of the operands:
 485 #
 486 # r = register field in the modr/m
 487 # m = modr/m
 488 # v = VEX "v" field
 489 # d = DREX "dst" field
 490 # i = immediate
 491 # s = register field of is4 or imz2 field
 492 #
 493 sub byte_code_compile($) {
 494     my($str) = @_;
 495     my $opr;
 496     my $opc;
 497     my @codes = ();
 498     my $litix = undef;
 499     my %oppos = ();
 500     my $i;
 501     my $op, $oq;
 502
 503     if ($str =~ /^(\S*)\:\s*(.*\S)\s*$/) {
 504         $opr = "\L$1";
 505         $opc = "\L$2";
 506     } else {
 507         $opr = '';
 508         $opc = $str;
 509     }
 510
 511     for ($i = 0; $i < length($opr); $i++) {
 512         $oppos{substr($opr,$i,1)} = $i;
 513     }
 514
 515     $prefix_ok = 1;
 516     foreach $op (split($opc)) {
 517         if ($op eq 'o16') {
 518             push(@codes, 0320);
 519         } elsif ($op eq 'o32') {
 520             push(@codes, 0321);
 521         } elsif ($op eq 'o64') {  # 64-bit operand size requiring REX.W
 522             push(@codes, 0324);
 523         } elsif ($op eq 'o64i') { # Implied 64-bit operand size (no REX.W)
 524             push(@codes, 0323);
 525         } elsif ($op eq 'a16') {
 526             push(@codes, 0310);
 527         } elsif ($op eq 'a32') {
 528             push(@codes, 0311);
 529         } elsif ($op eq 'a64') {
 530             push(@codes, 0313);
 531         } elsif ($op eq '!osp') {
 532             push(@codes, 0364);
 533         } elsif ($op eq '!asp') {
 534             push(@codes, 0365);
 535         } elsif ($op eq 'rex.l') {
 536             push(@codes, 0334);
 537         } elsif ($op eq 'repe') {
 538             push(@codes, 0335);
 539         } elsif ($prefix_ok && $op =~ /^(66|f2|f3|np)$/) {
 540             # 66/F2/F3 prefix used as an opcode extension, or np = no prefix
 541             if ($op eq '66') {
 542                 push(@codes, 0361);
 543             } elsif ($op eq 'f2') {
 544                 push(@codes, 0362);
 545             } elsif ($op eq 'f3') {
 546                 push(@codes, 0363);
 547             } else {
 548                 push(@codes, 0360);
 549             }
 550         } elsif ($op =~ /^[0-9a-f]{2}$/) {
 551             if (defined($litix) && $litix+$codes[$litix]+1 == scalar @codes) {
 552                 $codes[$litix]++;
 553                 push(@codes, hex $op);
 554             } else {
 555                 $litix = scalar(@codes);
 556                 push(@codes, 01, hex $op);
 557             }
 558             $prefix_ok = 0;
 559         } elsif ($op eq '/r') {
 560             if (!defined($oppos{'r'}) || !defined($oppos{'m'})) {
 561                 die "$0: $line: $op requires r and m operands\n";
 562             }
 563             push(@codes, 0100 + ($oppos{'m'} << 3) + $oppos{'r'});
 564             $prefix_ok = 0;
 565         } elsif ($op =~ m:^/([0-7])$:) {
 566             if (!defined($oppos{'m'})) {
 567                 die "$0: $line: $op requires m operand\n";
 568             }
 569             push(@codes, 0200 + ($oppos{'m'} << 3) + $1);
 570             $prefix_ok = 0;
 571         } elsif ($op =~ /^vex(|\..*)$/) {
 572             my ($m,$w,$l,$p) = (undef,2,undef,0);
 573             foreach $oq (split(/\./, $op)) {
 574                 if ($oq eq 'vex') {
 575                     # prefix
 576                 } elsif ($oq eq '128' || $oq eq 'l0') {
 577                     $l = 0;
 578                 } elsif ($oq eq '256' || $oq eq 'l1') {
 579                     $l = 1;
 580                 } elsif ($oq eq 'w0') {
 581                     $w = 0;
 582                 } elsif ($oq eq 'w1') {
 583                     $w = 1;
 584                 } elsif ($oq eq '66') {
 585                     $p = 1;
 586                 } elsif ($oq eq 'f3') {
 587                     $p = 2;
 588                 } elsif ($oq eq 'f2') {
 589                     $p = 3;
 590                 } elsif ($oq eq '0f') {
 591                     $m = 1;
 592                 } elsif ($oq eq '0f38') {
 593                     $m = 2;
 594                 } elsif ($oq eq '0f3a') {
 595                     $m = 3;
 596                 } elsif ($oq =~ /^m([0-9]+)$/) {
 597                     $m = $1+0;
 598                 } elsif ($oq eq 'nds' || $oq eq 'ndd') {
 599                     return undef if (!defined($oppos{'v'}));
 600                 } else {
 601                     die "$0: $line: undefined VEX subcode: $oq\n";
 602                 }
 603             }
 604             if (!defined($m) || !defined($w) || !defined($l) || !defined($p)) {
 605                 die "$0: $line: missing fields in VEX specification\n";
 606             }
 607             push(@codes, defined($oppos{'v'}) ? 0260+$oppos{'v'} : 0270,
 608                  $m, ($w << 3)+($l << 2)+$p);
 609             $prefix_ok = 0;
 610         } elsif ($op =~ /^drex(|..*)$/) {
 611             my ($oc0) = (0);
 612             foreach $oq (split(/\./, $op)) {
 613                 if ($oq eq 'drex') {
 614                     #prefix
 615                 } elsif ($oq eq 'oc0') {
 616                     $oc0 = 1;
 617                 } else {
 618                     die "$0: $line: undefined DREX subcode: $oq\n";
 619                 }
 620             }
 621             if (!defined($oppos{'d'})) {
 622                 die "$0: $line: DREX without a 'd' operand\n";
 623             }
 624             push(@codes, 0160+$oppos{'d'}+($oc0 ? 4 : 0));
 625         } elsif ($op =~ /^(imm8|imm8u|imm8s|imm16|imm32|imm32s|imm64|imm|immx|rel8|rel16|rel32|rel64|rel|seg|simm16|simm32|simm32s)$/) {
 626             if (!defined($oppos{'i'})) {
 627                 die "$0: $op without 'i' operand\n";
 628             }
 629             if ($op eq 'imm8s') {
 630                 push(@codes, 014+$oppos{'i'});
 631             } elsif ($op eq 'imm8') {
 632                 push(@codes, 020+$oppos{'i'});
 633             } elsif ($op eq 'imm8u') {
 634                 push(@codes, 024+$oppos{'i'});
 635             } elsif ($op eq 'imm16') {
 636                 push(@codes, 030+$oppos{'i'});
 637             } elsif ($op eq 'imm') { # 16 or 32 bit operand
 638                 push(@codes, 034+$oppos{'i'});
 639             } elsif ($op eq 'imm32') {
 640                 push(@codes, 040+$oppos{'i'});
 641             } elsif ($op eq 'immx') { # 16, 32 or 64 bit operand
 642                 push(@codes, 044+$oppos{'i'});
 643             } elsif ($op eq 'rel8') {
 644                 push(@codes, 050+$oppos{'i'});
 645             } elsif ($op eq 'rel64') {
 646                 push(@codes, 054+$oppos{'i'});
 647             } elsif ($op eq 'rel16') {
 648                 push(@codes, 060+$oppos{'i'});
 649             } elsif ($op eq 'rel') { # 16 or 32 bit relative operand
 650                 push(@codes, 064+$oppos{'i'});
 651             } elsif ($op eq 'rel32') {
 652                 push(@codes, 070+$oppos{'i'});
 653             } elsif ($op eq 'seg') {
 654                 push(@codes, 074+$oppos{'i'});
 655             } elsif ($op eq 'simm16') { # imm16 that can be bytified
 656                 if (!defined($s_pos)) {
 657                     die "$0: $line: $op without a +s byte\n";
 658                 }
 659                 $codes[$s_pos] += 0144;
 660                 push(@codes, 0140+$oppos{'i'});
 661             } elsif ($op eq 'simm32') { # imm32 that can be bytified
 662                 if (!defined($s_pos)) {
 663                     die "$0: $line: $op without a +s byte\n";
 664                 }
 665                 $codes[$s_pos] += 0154;
 666                 push(@codes, 0150+$oppos{'i'});
 667             } elsif ($op eq 'simm32s') {
 668                 # imm32 that can be bytified, sign extended
 669                 if (!defined($s_pos)) {
 670                     die "$0: $line: $op without a +s byte\n";
 671                 }
 672                 $codes[$s_pos] += 0154;
 673                 push(@codes, 0250+$oppos{'i'});
 674             }
 675             $prefix_ok = 0;
 676         } elsif ($op eq 'is4' || $op eq 'imz2') {
 677             if (!defined($oppos{'i'} || !defined($oppos{'s'}))) {
 678                 die "$0: $line: $op without 'i' and 's' operands\n";
 679             }
 680             push(@codes, 0172, ($oppos{'s'} << 3)+$oppos{'i'});
 681             $prefix_ok = 0;
 682         } elsif ($op =~ /^(is4|imz2)\=([0-9]+)$/) {
 683             my $imm = $2;
 684             if (!defined($oppos{'s'})) {
 685                 die "$0: $line: $op without 's' operand\n";
 686             }
 687             if ($imm < 0 || $imm > 15) {
 688                 die "$0: $line: invalid imm4 value for $op: $imm\n";
 689             }
 690             push(@codes, 0173, ($oppos{'s'} << 4) + $imm);
 691             $prefix_ok = 0;
 692         } elsif ($op =~ /^([0-9a-f]{2})\+s$/) {
 693             if (!defined($oppos{'i'})) {
 694                 die "$0: $op without 'i' operand\n";
 695             }
 696             $s_pos = scalar @codes;
 697             push(@codes, $oppos{'i'}, hex $1);
 698             $prefix_ok = 0;
 699         } elsif ($op =~ /^([0-9a-f]{2})\+c$/) {
 700             push(@codes, 0330, hex $1);
 701             $prefix_ok = 0;
 702         } elsif ($op =~ /^\\([0-7]+|x[0-9a-f]{2})$/) {
 703             # Escape to enter literal bytecodes
 704             push(@codes, oct $1);
 705         } else {
 706             die "$0: unknown operation: $op\n";
 707         }
 708     }
 709
 710     return @codes;
 711 }