nasm/insns.pl
H. Peter Anvin ff6e12da50 Reshuffle and move the bytecodes for segment register push/pop
Reshuffle the bytecodes for segment register push/pop to make more
sense, and move them from \4 to \344, thus freeing up the single-digit
bytecodes \4..\7 for future use.  It doesn't really make sense to use
single-digit bytecodes for this very oddball use.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-08 21:17:32 -07:00

798 lines
20 KiB
Perl
Executable File

#!/usr/bin/perl
#
# insns.pl produce insnsa.c, insnsd.c, insnsi.h, insnsn.c from insns.dat
#
# The Netwide Assembler is copyright (C) 1996 Simon Tatham and
# Julian Hall. All rights reserved. The software is
# redistributable under the license given in the file "LICENSE"
# distributed in the NASM archive.
# Opcode prefixes which need their own opcode tables
# LONGER PREFIXES FIRST!
@disasm_prefixes = qw(0F24 0F25 0F38 0F3A 0F7A 0FA6 0FA7 0F);
# This should match MAX_OPERANDS from nasm.h
$MAX_OPERANDS = 5;
# Add VEX prefixes
@vexlist = ();
for ($m = 0; $m < 32; $m++) {
for ($lp = 0; $lp < 8; $lp++) {
push(@vexlist, sprintf("VEX%02X%01X", $m, $lp));
}
}
@disasm_prefixes = (@vexlist, @disasm_prefixes);
@bytecode_count = (0) x 256;
print STDERR "Reading insns.dat...\n";
@args = ();
undef $output;
foreach $arg ( @ARGV ) {
if ( $arg =~ /^\-/ ) {
if ( $arg =~ /^\-([abdin])$/ ) {
$output = $1;
} else {
die "$0: Unknown option: ${arg}\n";
}
} else {
push (@args, $arg);
}
}
$fname = "insns.dat" unless $fname = $args[0];
open (F, $fname) || die "unable to open $fname";
%dinstables = ();
@bytecode_list = ();
$line = 0;
$insns = 0;
while (<F>) {
$line++;
chomp;
next if ( /^\s*(\;.*|)$/ ); # comments or blank lines
unless (/^\s*(\S+)\s+(\S+)\s+(\S+|\[.*\])\s+(\S+)\s*$/) {
warn "line $line does not contain four fields\n";
next;
}
@fields = ($1, $2, $3, $4);
($formatted, $nd) = format_insn(@fields);
if ($formatted) {
$insns++;
$aname = "aa_$fields[0]";
push @$aname, $formatted;
}
if ( $fields[0] =~ /cc$/ ) {
# Conditional instruction
$k_opcodes_cc{$fields[0]}++;
} else {
# Unconditional instruction
$k_opcodes{$fields[0]}++;
}
if ($formatted && !$nd) {
push @big, $formatted;
my @sseq = startseq($fields[2]);
foreach $i (@sseq) {
if (!defined($dinstables{$i})) {
$dinstables{$i} = [];
}
push(@{$dinstables{$i}}, $#big);
}
}
}
close F;
#
# Generate the bytecode array. At this point, @bytecode_list contains
# the full set of bytecodes.
#
# Sort by descending length
@bytecode_list = sort { scalar(@$b) <=> scalar(@$a) } @bytecode_list;
@bytecode_array = ();
%bytecode_pos = ();
$bytecode_next = 0;
foreach $bl (@bytecode_list) {
my $h = hexstr(@$bl);
next if (defined($bytecode_pos{$h}));
push(@bytecode_array, $bl);
while ($h ne '') {
$bytecode_pos{$h} = $bytecode_next;
$h = substr($h, 2);
$bytecode_next++;
}
}
undef @bytecode_list;
@opcodes = sort keys(%k_opcodes);
@opcodes_cc = sort keys(%k_opcodes_cc);
if ( !defined($output) || $output eq 'b') {
print STDERR "Writing insnsb.c...\n";
open B, ">insnsb.c";
print B "/* This file auto-generated from insns.dat by insns.pl" .
" - don't edit it */\n\n";
print B "#include \"nasm.h\"\n";
print B "#include \"insns.h\"\n\n";
print B "const uint8_t nasm_bytecodes[$bytecode_next] = {\n";
$p = 0;
foreach $bl (@bytecode_array) {
printf B " /* %5d */ ", $p;
foreach $d (@$bl) {
printf B "%#o,", $d;
$p++;
}
printf B "\n";
}
print B "};\n";
print B "\n";
print B "/*\n";
print B " * Bytecode frequencies (including reuse):\n";
print B " *\n";
for ($i = 0; $i < 32; $i++) {
print B " *";
for ($j = 0; $j < 256; $j += 32) {
print B " |" if ($j);
printf B " %3o:%4d", $i+$j, $bytecode_count[$i+$j];
}
print B "\n";
}
print B " */\n";
close B;
}
if ( !defined($output) || $output eq 'a' ) {
print STDERR "Writing insnsa.c...\n";
open A, ">insnsa.c";
print A "/* This file auto-generated from insns.dat by insns.pl" .
" - don't edit it */\n\n";
print A "#include \"nasm.h\"\n";
print A "#include \"insns.h\"\n\n";
foreach $i (@opcodes, @opcodes_cc) {
print A "static const struct itemplate instrux_${i}[] = {\n";
$aname = "aa_$i";
foreach $j (@$aname) {
print A " ", codesubst($j), "\n";
}
print A " ITEMPLATE_END\n};\n\n";
}
print A "const struct itemplate * const nasm_instructions[] = {\n";
foreach $i (@opcodes, @opcodes_cc) {
print A " instrux_${i},\n";
}
print A "};\n";
close A;
}
if ( !defined($output) || $output eq 'd' ) {
print STDERR "Writing insnsd.c...\n";
open D, ">insnsd.c";
print D "/* This file auto-generated from insns.dat by insns.pl" .
" - don't edit it */\n\n";
print D "#include \"nasm.h\"\n";
print D "#include \"insns.h\"\n\n";
print D "static const struct itemplate instrux[] = {\n";
$n = 0;
foreach $j (@big) {
printf D " /* %4d */ %s\n", $n++, codesubst($j);
}
print D "};\n";
foreach $h (sort(keys(%dinstables))) {
next if ($h eq ''); # Skip pseudo-instructions
print D "\nstatic const struct itemplate * const itable_${h}[] = {\n";
foreach $j (@{$dinstables{$h}}) {
print D " instrux + $j,\n";
}
print D "};\n";
}
@prefix_list = ();
foreach $h (@disasm_prefixes, '') {
for ($c = 0; $c < 256; $c++) {
$nn = sprintf("%s%02X", $h, $c);
if ($is_prefix{$nn} || defined($dinstables{$nn})) {
# At least one entry in this prefix table
push(@prefix_list, $h);
$is_prefix{$h} = 1;
last;
}
}
}
foreach $h (@prefix_list) {
print D "\n";
print D "static " unless ($h eq '');
print D "const struct disasm_index ";
print D ($h eq '') ? 'itable' : "itable_$h";
print D "[256] = {\n";
for ($c = 0; $c < 256; $c++) {
$nn = sprintf("%s%02X", $h, $c);
if ($is_prefix{$nn}) {
die "$fname: ambiguous decoding of $nn\n"
if (defined($dinstables{$nn}));
printf D " { itable_%s, -1 },\n", $nn;
} elsif (defined($dinstables{$nn})) {
printf D " { itable_%s, %u },\n",
$nn, scalar(@{$dinstables{$nn}});
} else {
printf D " { NULL, 0 },\n";
}
}
print D "};\n";
}
print D "\nconst struct disasm_index * const itable_VEX[32][8] = {\n ";
for ($m = 0; $m < 32; $m++) {
print D " {\n";
for ($lp = 0; $lp < 8; $lp++) {
$vp = sprintf("VEX%02X%01X", $m, $lp);
if ($is_prefix{$vp}) {
printf D " itable_%s,\n", $vp;
} else {
print D " NULL,\n";
}
}
print D " },";
}
print D "\n};\n";
close D;
}
if ( !defined($output) || $output eq 'i' ) {
print STDERR "Writing insnsi.h...\n";
open I, ">insnsi.h";
print I "/* This file is auto-generated from insns.dat by insns.pl" .
" - don't edit it */\n\n";
print I "/* This file in included by nasm.h */\n\n";
print I "/* Instruction names */\n\n";
print I "#ifndef NASM_INSNSI_H\n";
print I "#define NASM_INSNSI_H 1\n\n";
print I "enum opcode {\n";
$maxlen = 0;
foreach $i (@opcodes, @opcodes_cc) {
print I "\tI_${i},\n";
$len = length($i);
$len++ if ( $i =~ /cc$/ ); # Condition codes can be 3 characters long
$maxlen = $len if ( $len > $maxlen );
}
print I "\tI_none = -1\n";
print I "\n};\n\n";
print I "#define MAX_INSLEN ", $maxlen, "\n";
print I "#define FIRST_COND_OPCODE I_", $opcodes_cc[0], "\n\n";
print I "#endif /* NASM_INSNSI_H */\n";
close I;
}
if ( !defined($output) || $output eq 'n' ) {
print STDERR "Writing insnsn.c...\n";
open N, ">insnsn.c";
print N "/* This file is auto-generated from insns.dat by insns.pl" .
" - don't edit it */\n\n";
print N "#include \"tables.h\"\n\n";
print N "const char * const nasm_insn_names[] = {";
$first = 1;
foreach $i (@opcodes, @opcodes_cc) {
print N "," if ( !$first );
$first = 0;
$ilower = $i;
$ilower =~ s/cc$//; # Remove conditional cc suffix
$ilower =~ tr/A-Z/a-z/; # Change to lower case (Perl 4 compatible)
print N "\n\t\"${ilower}\"";
}
print N "\n};\n";
close N;
}
printf STDERR "Done: %d instructions\n", $insns;
# Count primary bytecodes, for statistics
sub count_bytecodes(@) {
my $skip = 0;
foreach my $bc (@_) {
if ($skip) {
$skip--;
next;
}
$bytecode_count[$bc]++;
if ($bc >= 01 && $bc <= 03) {
$skip = $bc;
} elsif (($bc & ~03) == 010) {
$skip = 1;
} elsif (($bc & ~013) == 0144) {
$skip = 1;
} elsif ($bc == 0172) {
$skip = 1;
} elsif ($bc >= 0260 && $bc <= 0270) {
$skip = 2;
} elsif ($bc == 0330) {
$skip = 1;
}
}
}
sub format_insn(@) {
my ($opcode, $operands, $codes, $flags) = @_;
my $num, $nd = 0;
my @bytecode;
return (undef, undef) if $operands eq "ignore";
# format the operands
$operands =~ s/:/|colon,/g;
$operands =~ s/mem(\d+)/mem|bits$1/g;
$operands =~ s/mem/memory/g;
$operands =~ s/memory_offs/mem_offs/g;
$operands =~ s/imm(\d+)/imm|bits$1/g;
$operands =~ s/imm/immediate/g;
$operands =~ s/rm(\d+)/rm_gpr|bits$1/g;
$operands =~ s/(mmx|xmm|ymm)rm/rm_$1/g;
$operands =~ s/\=([0-9]+)/same_as|$1/g;
if ($operands eq 'void') {
@ops = ();
} else {
@ops = split(/\,/, $operands);
}
$num = scalar(@ops);
while (scalar(@ops) < $MAX_OPERANDS) {
push(@ops, '0');
}
$operands = join(',', @ops);
$operands =~ tr/a-z/A-Z/;
# format the flags
$flags =~ s/,/|IF_/g;
$flags =~ s/(\|IF_ND|IF_ND\|)//, $nd = 1 if $flags =~ /IF_ND/;
$flags = "IF_" . $flags;
@bytecode = (decodify($codes), 0);
push(@bytecode_list, [@bytecode]);
$codes = hexstr(@bytecode);
count_bytecodes(@bytecode);
("{I_$opcode, $num, {$operands}, \@\@CODES-$codes\@\@, $flags},", $nd);
}
#
# Look for @@CODES-xxx@@ sequences and replace them with the appropriate
# offset into nasm_bytecodes
#
sub codesubst($) {
my($s) = @_;
my $n;
while ($s =~ /\@\@CODES-([0-9A-F]+)\@\@/) {
my $pos = $bytecode_pos{$1};
if (!defined($pos)) {
die "$fname: no position assigned to byte code $1\n";
}
$s = $` . "nasm_bytecodes+${pos}" . "$'";
}
return $s;
}
sub addprefix ($@) {
my ($prefix, @list) = @_;
my $x;
my @l = ();
foreach $x (@list) {
push(@l, sprintf("%s%02X", $prefix, $x));
}
return @l;
}
#
# Turn a code string into a sequence of bytes
#
sub decodify($) {
# Although these are C-syntax strings, by convention they should have
# only octal escapes (for directives) and hexadecimal escapes
# (for verbatim bytes)
my($codestr) = @_;
if ($codestr =~ /^\s*\[([^\]]*)\]\s*$/) {
return byte_code_compile($1);
}
my $c = $codestr;
my @codes = ();
while ($c ne '') {
if ($c =~ /^\\x([0-9a-f]+)(.*)$/i) {
push(@codes, hex $1);
$c = $2;
next;
} elsif ($c =~ /^\\([0-7]{1,3})(.*)$/) {
push(@codes, oct $1);
$c = $2;
next;
} else {
die "$fname: unknown code format in \"$codestr\"\n";
}
}
return @codes;
}
# Turn a numeric list into a hex string
sub hexstr(@) {
my $s = '';
my $c;
foreach $c (@_) {
$s .= sprintf("%02X", $c);
}
return $s;
}
# Here we determine the range of possible starting bytes for a given
# instruction. We need only consider the codes:
# \1 \2 \3 mean literal bytes, of course
# \4 \5 \6 \7 mean PUSH/POP of segment registers: special case
# \1[0123] mean byte plus register value
# \330 means byte plus condition code
# \0 or \340 mean give up and return empty set
# \17[234] skip is4 control byte
# \26x \270 skip VEX control bytes
sub startseq($) {
my ($codestr) = @_;
my $word, @range;
my @codes = ();
my $c = $codestr;
my $c0, $c1, $i;
my $prefix = '';
@codes = decodify($codestr);
while ($c0 = shift(@codes)) {
$c1 = $codes[0];
if ($c0 == 01 || $c0 == 02 || $c0 == 03) {
# Fixed byte string
my $fbs = $prefix;
while (1) {
if ($c0 == 01 || $c0 == 02 || $c0 == 03) {
while ($c0--) {
$fbs .= sprintf("%02X", shift(@codes));
}
} else {
last;
}
$c0 = shift(@codes);
}
foreach $pfx (@disasm_prefixes) {
if (substr($fbs, 0, length($pfx)) eq $pfx) {
$prefix = $pfx;
$fbs = substr($fbs, length($pfx));
last;
}
}
if ($fbs ne '') {
return ($prefix.substr($fbs,0,2));
}
unshift(@codes, $c0);
} elsif ($c0 >= 010 && $c0 <= 013) {
return addprefix($prefix, $c1..($c1+7));
} elsif (($c0 & ~013) == 0144) {
return addprefix($prefix, $c1, $c1|2);
} elsif ($c0 == 0330) {
return addprefix($prefix, $c1..($c1+15));
} elsif ($c0 == 0 || $c0 == 0340) {
return $prefix;
} elsif ($c0 == 0344) {
return addprefix($prefix, 0x06, 0x0E, 0x16, 0x1E);
} elsif ($c0 == 0345) {
return addprefix($prefix, 0x07, 0x17, 0x1F);
} elsif ($c0 == 0346) {
return addprefix($prefix, 0xA0, 0xA8);
} elsif ($c0 == 0347) {
return addprefix($prefix, 0xA1, 0xA9);
} elsif (($c0 & ~3) == 0260 || $c0 == 0270) {
my $m,$wlp,$vxp;
$m = shift(@codes);
$wlp = shift(@codes);
$prefix .= sprintf('VEX%02X%01X', $m, $wlp & 7);
} elsif ($c0 >= 0172 && $c0 <= 174) {
shift(@codes); # Skip is4 control byte
} else {
# We really need to be able to distinguish "forbidden"
# and "ignorable" codes here
}
}
return $prefix;
}
#
# This function takes a series of byte codes in a format which is more
# typical of the Intel documentation, and encode it.
#
# The format looks like:
#
# [operands: opcodes]
#
# The operands word lists the order of the operands:
#
# r = register field in the modr/m
# m = modr/m
# v = VEX "v" field
# d = DREX "dst" field
# i = immediate
# s = register field of is4/imz2 field
# - = implicit (unencoded) operand
#
# For an operand that should be filled into more than one field,
# enter it as e.g. "r+v".
#
sub byte_code_compile($) {
my($str) = @_;
my $opr;
my $opc;
my @codes = ();
my $litix = undef;
my %oppos = ();
my $i;
my $op, $oq;
unless ($str =~ /^(([^\s:]*)\:|)\s*(.*\S)\s*$/) {
die "$fname: $line: cannot parse: [$str]\n";
}
$opr = "\L$2";
$opc = "\L$3";
my $op = 0;
for ($i = 0; $i < length($opr); $i++) {
my $c = substr($opr,$i,1);
if ($c eq '+') {
$op--;
} else {
$oppos{$c} = $op++;
}
}
$prefix_ok = 1;
foreach $op (split(/\s*(?:\s|(?=[\/\\]))/, $opc)) {
if ($op eq 'o16') {
push(@codes, 0320);
} elsif ($op eq 'o32') {
push(@codes, 0321);
} elsif ($op eq 'o64') { # 64-bit operand size requiring REX.W
push(@codes, 0324);
} elsif ($op eq 'o64nw') { # Implied 64-bit operand size (no REX.W)
push(@codes, 0323);
} elsif ($op eq 'a16') {
push(@codes, 0310);
} elsif ($op eq 'a32') {
push(@codes, 0311);
} elsif ($op eq 'a64') {
push(@codes, 0313);
} elsif ($op eq '!osp') {
push(@codes, 0364);
} elsif ($op eq '!asp') {
push(@codes, 0365);
} elsif ($op eq 'rex.l') {
push(@codes, 0334);
} elsif ($op eq 'repe') {
push(@codes, 0335);
} elsif ($prefix_ok && $op =~ /^(66|f2|f3|np)$/) {
# 66/F2/F3 prefix used as an opcode extension, or np = no prefix
if ($op eq '66') {
push(@codes, 0361);
} elsif ($op eq 'f2') {
push(@codes, 0362);
} elsif ($op eq 'f3') {
push(@codes, 0363);
} else {
push(@codes, 0360);
}
} elsif ($op =~ /^[0-9a-f]{2}$/) {
if (defined($litix) && $litix+$codes[$litix]+1 == scalar @codes) {
$codes[$litix]++;
push(@codes, hex $op);
} else {
$litix = scalar(@codes);
push(@codes, 01, hex $op);
}
$prefix_ok = 0;
} elsif ($op eq '/r') {
if (!defined($oppos{'r'}) || !defined($oppos{'m'})) {
die "$fname: $line: $op requires r and m operands\n";
}
push(@codes, 0100 + ($oppos{'m'} << 3) + $oppos{'r'});
$prefix_ok = 0;
} elsif ($op =~ m:^/([0-7])$:) {
if (!defined($oppos{'m'})) {
die "$fname: $line: $op requires m operand\n";
}
push(@codes, 0200 + ($oppos{'m'} << 3) + $1);
$prefix_ok = 0;
} elsif ($op =~ /^vex(|\..*)$/) {
my ($m,$w,$l,$p) = (undef,2,undef,0);
my $has_nds = 0;
foreach $oq (split(/\./, $op)) {
if ($oq eq 'vex') {
# prefix
} elsif ($oq eq '128' || $oq eq 'l0') {
$l = 0;
} elsif ($oq eq '256' || $oq eq 'l1') {
$l = 1;
} elsif ($oq eq 'w0') {
$w = 0;
} elsif ($oq eq 'w1') {
$w = 1;
} elsif ($oq eq 'wx') {
$w = 2;
} elsif ($oq eq 'ww') {
$w = 3;
} elsif ($oq eq '66') {
$p = 1;
} elsif ($oq eq 'f3') {
$p = 2;
} elsif ($oq eq 'f2') {
$p = 3;
} elsif ($oq eq '0f') {
$m = 1;
} elsif ($oq eq '0f38') {
$m = 2;
} elsif ($oq eq '0f3a') {
$m = 3;
} elsif ($oq =~ /^m([0-9]+)$/) {
$m = $1+0;
} elsif ($oq eq 'nds' || $oq eq 'ndd') {
if (!defined($oppos{'v'})) {
die "$fname: $line: vex.$oq without 'v' operand\n";
}
$has_nds = 1;
} else {
die "$fname: $line: undefined VEX subcode: $oq\n";
}
}
if (!defined($m) || !defined($w) || !defined($l) || !defined($p)) {
die "$fname: $line: missing fields in VEX specification\n";
}
if (defined($oppos{'v'}) && !$has_nds) {
die "$fname: $line: 'v' operand without vex.nds or vex.ndd\n";
}
push(@codes, defined($oppos{'v'}) ? 0260+$oppos{'v'} : 0270,
$m, ($w << 3)+($l << 2)+$p);
$prefix_ok = 0;
} elsif ($op =~ /^\/drex([01])$/) {
my $oc0 = $1;
if (!defined($oppos{'d'})) {
die "$fname: $line: DREX without a 'd' operand\n";
}
# Note the use of *unshift* here, as opposed to *push*.
# This is because NASM want this byte code at the start of
# the instruction sequence, but the AMD documentation puts
# this at (roughly) the position of the drex byte itself.
# This allows us to match the AMD documentation and still
# do the right thing.
unshift(@codes, 0160+$oppos{'d'}+($oc0 ? 4 : 0));
} elsif ($op =~ /^(ib\,s|ib|ibx|ib\,w|iw|iwd|id|idx|iwdq|rel|rel8|rel16|rel32|iq|seg|ibw|ibd|ibd,s)$/) {
if (!defined($oppos{'i'})) {
die "$fname: $line: $op without 'i' operand\n";
}
if ($op eq 'ib,s') { # Signed imm8
push(@codes, 014+$oppos{'i'});
} elsif ($op eq 'ib') { # imm8
push(@codes, 020+$oppos{'i'});
} elsif ($op eq 'ib,u') { # Unsigned imm8
push(@codes, 024+$oppos{'i'});
} elsif ($op eq 'iw') { # imm16
push(@codes, 030+$oppos{'i'});
} elsif ($op eq 'ibx') { # imm8 sign-extended to opsize
push(@codes, 0274+$oppos{'i'});
} elsif ($op eq 'iwd') { # imm16 or imm32, depending on opsize
push(@codes, 034+$oppos{'i'});
} elsif ($op eq 'id') { # imm32
push(@codes, 040+$oppos{'i'});
} elsif ($op eq 'idx') { # imm32 extended to 64 bits
push(@codes, 0254+$oppos{'i'});
} elsif ($op eq 'iwdq') { # imm16/32/64, depending on opsize
push(@codes, 044+$oppos{'i'});
} elsif ($op eq 'rel8') {
push(@codes, 050+$oppos{'i'});
} elsif ($op eq 'iq') {
push(@codes, 054+$oppos{'i'});
} elsif ($op eq 'rel16') {
push(@codes, 060+$oppos{'i'});
} elsif ($op eq 'rel') { # 16 or 32 bit relative operand
push(@codes, 064+$oppos{'i'});
} elsif ($op eq 'rel32') {
push(@codes, 070+$oppos{'i'});
} elsif ($op eq 'seg') {
push(@codes, 074+$oppos{'i'});
} elsif ($op eq 'ibw') { # imm16 that can be bytified
if (!defined($s_pos)) {
die "$fname: $line: $op without a +s byte\n";
}
$codes[$s_pos] += 0144;
push(@codes, 0140+$oppos{'i'});
} elsif ($op eq 'ibd') { # imm32 that can be bytified
if (!defined($s_pos)) {
die "$fname: $line: $op without a +s byte\n";
}
$codes[$s_pos] += 0154;
push(@codes, 0150+$oppos{'i'});
} elsif ($op eq 'ibd,s') {
# imm32 that can be bytified, sign extended to 64 bits
if (!defined($s_pos)) {
die "$fname: $line: $op without a +s byte\n";
}
$codes[$s_pos] += 0154;
push(@codes, 0250+$oppos{'i'});
}
$prefix_ok = 0;
} elsif ($op eq '/is4') {
if (!defined($oppos{'s'})) {
die "$fname: $line: $op without 's' operand\n";
}
if (defined($oppos{'i'})) {
push(@codes, 0172, ($oppos{'s'} << 3)+$oppos{'i'});
} else {
push(@codes, 0174, $oppos{'s'});
}
$prefix_ok = 0;
} elsif ($op =~ /^\/is4\=([0-9]+)$/) {
my $imm = $1;
if (!defined($oppos{'s'})) {
die "$fname: $line: $op without 's' operand\n";
}
if ($imm < 0 || $imm > 15) {
die "$fname: $line: invalid imm4 value for $op: $imm\n";
}
push(@codes, 0173, ($oppos{'s'} << 4) + $imm);
$prefix_ok = 0;
} elsif ($op =~ /^([0-9a-f]{2})\+s$/) {
if (!defined($oppos{'i'})) {
die "$fname: $line: $op without 'i' operand\n";
}
$s_pos = scalar @codes;
push(@codes, $oppos{'i'}, hex $1);
$prefix_ok = 0;
} elsif ($op =~ /^([0-9a-f]{2})\+c$/) {
push(@codes, 0330, hex $1);
$prefix_ok = 0;
} elsif ($op =~ /^\\([0-7]+|x[0-9a-f]{2})$/) {
# Escape to enter literal bytecodes
push(@codes, oct $1);
} else {
die "$fname: $line: unknown operation: $op\n";
}
}
return @codes;
}