# 6. Don't use [or hand-code with .byte] "rep ret." "ret" mnemonic is
# required to identify the spots, where to inject Win64 epilogue!
# But on the pros, it's then prefixed with rep automatically:-)
+# 7. Due to MASM limitations [and certain general counter-intuitivity
+# of ip-relative addressing] generation of position-independent
+# code is assisted by synthetic directive, .picmeup, which puts
+# address of the *next* instruction into target register.
+#
+# Example 1:
+# .picmeup %rax
+# lea .Label-.(%rax),%rax
+# Example 2:
+# .picmeup %rcx
+# .Lpic_point:
+# ...
+# lea .Label-.Lpic_point(%rcx),%rbp
my $output = shift;
open STDOUT,">$output" || die "can't open $output: $!";
}
sub out {
my $self = shift;
- sprintf $masm?"%s":"\$%s",$self->{value};
+
+ if (!$masm) {
+ # Solaris /usr/ccs/bin/as can't handle multiplications
+ # in $self->{value}
+ $self->{value} =~ s/(?<![0-9a-f])(0[x0-9a-f]+)/oct($1)/egi;
+ $self->{value} =~ s/([0-9]+\s*[\*\/\%]\s*[0-9]+)/eval($1)/eg;
+ sprintf "\$%s",$self->{value};
+ } else {
+ $self->{value} =~ s/0x([0-9a-f]+)/0$1h/ig;
+ sprintf "%s",$self->{value};
+ }
}
}
{ package ea; # pick up effective addresses: expr(%reg,%reg,scale)
$ret = $self;
$line = substr($line,@+[0]); $line =~ s/^\s+//;
- $self->{label} =~ s/\.L/\$L/g;
$self->{base} =~ s/^%//;
$self->{index} =~ s/^%// if (defined($self->{index}));
}
my $self = shift;
my $sz = shift;
+ # Silently convert all EAs to 64-bit. This is required for
+ # elder GNU assembler and results in more compact code,
+ # *but* most importantly AES module depends on this feature!
+ $self->{index} =~ s/^[er](.?[0-9xpi])[d]?$/r\1/;
+ $self->{base} =~ s/^[er](.?[0-9xpi])[d]?$/r\1/;
+
if (!$masm) {
- # elder GNU assembler insists on 64-bit EAs:-(
- # on pros side, this results in more compact code:-)
- $self->{index} =~ s/^[er](.?[0-9xp])[d]?$/r\1/;
- $self->{base} =~ s/^[er](.?[0-9xp])[d]?$/r\1/;
+ # Solaris /usr/ccs/bin/as can't handle multiplications
+ # in $self->{label}
+ $self->{label} =~ s/(?<![0-9a-f])(0[x0-9a-f]+)/oct($1)/egi;
+ $self->{label} =~ s/([0-9]+\s*[\*\/\%]\s*[0-9]+)/eval($1)/eg;
if (defined($self->{index})) {
- sprintf "%s(%%%s,%%%s,%d)", $self->{label},$self->{base},
+ sprintf "%s(%%%s,%%%s,%d)",
+ $self->{label},$self->{base},
$self->{index},$self->{scale};
- }
- else {
+ } else {
sprintf "%s(%%%s)", $self->{label},$self->{base};
}
} else {
%szmap = ( b=>"BYTE", w=>"WORD", l=>"DWORD", q=>"QWORD" );
+ $self->{label} =~ s/\./\$/g;
+ $self->{label} =~ s/0x([0-9a-f]+)/0$1h/ig;
+ $self->{label} = "($self->{label})" if ($self->{label} =~ /[\*\+\-\/]/);
+
if (defined($self->{index})) {
sprintf "%s PTR %s[%s*%d+%s]",$szmap{$sz},
$self->{label},
$self->{index},$self->{scale},
$self->{base};
- }
- else {
+ } else {
sprintf "%s PTR %s[%s]",$szmap{$sz},
$self->{label},$self->{base};
}
local *line = shift;
undef $ret;
my $dir;
+ my %opcode = # lea 2f-1f(%rip),%dst; 1: nop; 2:
+ ( "%rax"=>0x01058d48, "%rcx"=>0x010d8d48,
+ "%rdx"=>0x01158d48, "%rbx"=>0x011d8d48,
+ "%rsp"=>0x01258d48, "%rbp"=>0x012d8d48,
+ "%rsi"=>0x01358d48, "%rdi"=>0x013d8d48,
+ "%r8" =>0x01058d4c, "%r9" =>0x010d8d4c,
+ "%r10"=>0x01158d4c, "%r11"=>0x011d8d4c,
+ "%r12"=>0x01258d4c, "%r13"=>0x012d8d4c,
+ "%r14"=>0x01358d4c, "%r15"=>0x013d8d4c );
if ($line =~ /^\s*(\.\w+)/) {
if (!$masm) {
$self->{value} = $1;
$line =~ s/\@abi\-omnipotent/\@function/;
$line =~ s/\@function.*/\@function/;
- $self->{value} = $line;
+ if ($line =~ /\.picmeup\s+(%r[\w]+)/i) {
+ $self->{value} = sprintf "\t.long\t0x%x,0x90000000",$opcode{$1};
+ } else {
+ $self->{value} = $line;
+ }
$line = "";
return $self;
}
undef $self->{value};
$line = substr($line,@+[0]); $line =~ s/^\s+//;
SWITCH: for ($dir) {
- /\.(text|data)/
+ /\.(text)/
&& do { my $v=undef;
$v="$current_segment\tENDS\n" if ($current_segment);
- $current_segment = "_$1";
+ $current_segment = "_$1\$";
$current_segment =~ tr/[a-z]/[A-Z]/;
- $v.="$current_segment\tSEGMENT PARA";
+ $v.="$current_segment\tSEGMENT ALIGN(64) 'CODE'";
$self->{value} = $v;
last;
};
/\.globl/ && do { $self->{value} = "PUBLIC\t".$line; last; };
/\.type/ && do { ($sym,$type,$narg) = split(',',$line);
- if ($type eq "\@function")
- { undef $current_function;
+ if ($type eq "\@function") {
+ undef $current_function;
$current_function->{name} = $sym;
$current_function->{abi} = "svr4";
$current_function->{narg} = $narg;
- }
- elsif ($type eq "\@abi-omnipotent")
- { undef $current_function;
+ } elsif ($type eq "\@abi-omnipotent") {
+ undef $current_function;
$current_function->{name} = $sym;
}
last;
};
- /\.size/ && do { if (defined($current_function))
- { $self->{value}="$current_function->{name}\tENDP";
+ /\.size/ && do { if (defined($current_function)) {
+ $self->{value}="$current_function->{name}\tENDP";
undef $current_function;
}
last;
$self->{value} .= sprintf"0%Xh",oct($last);
last;
};
+ /\.picmeup/ && do { $self->{value} = sprintf"\tDD\t 0%Xh,090000000h",$opcode{$line};
+ last;
+ };
}
$line = "";
}
if (!$masm) {
printf "\t%s\t%s,%s", $opcode->out($dst->size()),
$src->out($sz),$dst->out($sz);
- }
- else {
+ } else {
printf "\t%s\t%s,%s", $opcode->out(),
$dst->out($sz),$src->out($sz);
}
- }
- elsif (defined($src)) {
+ } elsif (defined($src)) {
printf "\t%s\t%s",$opcode->out(),$src->out($sz);
} else {
printf "\t%s",$opcode->out();
# arguments passed to callee, *but* not less than 4! This means that
# upon function entry point 5th argument resides at 40(%rsp), as well
# as that 32 bytes from 8(%rsp) can always be used as temporal
-# storage [without allocating a frame].
+# storage [without allocating a frame]. One can actually argue that
+# one can assume a "red zone" above stack pointer under Win64 as well.
+# Point is that at apparently no occasion Windows kernel would alter
+# the area above user stack pointer in true asynchronous manner...
#
# All the above means that if assembler programmer adheres to Unix
# register and stack layout, but disregards the "red zone" existense,