$output=shift;
$win64a=1 if ($output =~ /win64a.[s|asm]/);
open STDOUT,">$output" || die "can't open $output: $!";
if (defined($win64a)) {
$dat="%rcx"; $len="%rdx"; $inp="%rsi"; $out="%rdi"; } else {
$dat="%rdi"; $len="%rsi"; $inp="%rdx"; $out="%rcx"; }
$XX="%r10";
$TX="%r8";
$YY="%r11";
$TY="%r9";
sub PTR() {
my $ret=shift;
if (defined($win64a)) {
$ret =~ s/\[([\S]+)\+([\S]+)\]/[$2+$1]/g; $ret =~ s/:([^\[]+)\[([^\]]+)\]/:[$2+$1]/g; } else {
$ret =~ s/[\+\*]/,/g; $ret =~ s/\[([^\]]+)\]/($1)/g; }
$ret;
}
$code=<<___ if (!defined($win64a));
.text
.globl RC4
.type RC4,\@function
.align 16
RC4: or $len,$len
jne .Lentry
repret
.Lentry:
___
$code=<<___ if (defined($win64a));
_TEXT SEGMENT
PUBLIC RC4
ALIGN 16
RC4 PROC
or $len,$len
jne .Lentry
repret
.Lentry:
push %rdi
push %rsi
sub \$40,%rsp
mov %r8,$inp
mov %r9,$out
___
$code.=<<___;
add \$8,$dat
movl `&PTR("DWORD:-8[$dat]")`,$XX movl `&PTR("DWORD:-4[$dat]")`,$YY cmpl \$-1,`&PTR("DWORD:256[$dat]")`
je .LRC4_CHAR
test \$-8,$len
jz .Lloop1
.align 16
.Lloop8:
inc $XX movl `&PTR("DWORD:[$dat+$XX*4]")`,$TX add $TX movl `&PTR("DWORD:[$dat+$YY*4]")`,$TY movl $TX movl $TY add $TX inc $XX movl `&PTR("DWORD:[$dat+$XX*4]")`,$TX movb `&PTR("BYTE:[$dat+$TY*4]")`,%al
___
for ($i=1;$i<=6;$i++) {
$code.=<<___;
add $TX ror \$8,%rax
movl `&PTR("DWORD:[$dat+$YY*4]")`,$TY movl $TX movl $TY add $TX inc $XX movl `&PTR("DWORD:[$dat+$XX*4]")`,$TX movb `&PTR("BYTE:[$dat+$TY*4]")`,%al
___
}
$code.=<<___;
add $TX ror \$8,%rax
movl `&PTR("DWORD:[$dat+$YY*4]")`,$TY movl $TX movl $TY sub \$8,$len
add $TY movb `&PTR("BYTE:[$dat+$TX*4]")`,%al
ror \$8,%rax
add \$8,$inp
add \$8,$out
xor `&PTR("QWORD:-8[$inp]")`,%rax
mov %rax,`&PTR("QWORD:-8[$out]")`
test \$-8,$len
jnz .Lloop8
cmp \$0,$len
jne .Lloop1
.Lexit:
movl $XX movl $YY___
$code.=<<___ if (defined($win64a));
add \$40,%rsp
pop %rsi
pop %rdi
___
$code.=<<___;
repret
.align 16
.Lloop1:
movzb `&PTR("BYTE:[$inp]")`,%eax
inc $XX movl `&PTR("DWORD:[$dat+$XX*4]")`,$TX add $TX movl `&PTR("DWORD:[$dat+$YY*4]")`,$TY movl $TX movl $TY add $TY movl `&PTR("DWORD:[$dat+$TX*4]")`,$TY xor $TY,%rax
inc $inp
movb %al,`&PTR("BYTE:[$out]")`
inc $out
dec $len
jnz .Lloop1
jmp .Lexit
.align 16
.LRC4_CHAR:
inc $XX movzb `&PTR("BYTE:[$dat+$XX]")`,$TX add $TX movzb `&PTR("BYTE:[$dat+$YY]")`,$TY movb $TX movb $TY add $TX movzb `&PTR("BYTE:[$dat+$TY]")`,$TY xorb `&PTR("BYTE:[$inp]")`,$TY movb $TY inc $inp
inc $out
dec $len
jnz .LRC4_CHAR
jmp .Lexit
___
$code.=<<___ if (defined($win64a));
RC4 ENDP
_TEXT ENDS
END
___
$code.=<<___ if (!defined($win64a));
.size RC4,.-RC4
___
$code =~ s/$code =~ s/\`([^\`]*)\`/eval $1/gem;
if (defined($win64a)) {
$code =~ s/\.align/ALIGN/gm;
$code =~ s/[\$%]//gm;
$code =~ s/\.L/\$L/gm;
$code =~ s/([\w]+)([\s]+)([\S]+),([\S]+)/$1$2$4,$3/gm;
$code =~ s/([QD]*WORD|BYTE):/$1 PTR/gm;
$code =~ s/mov[bwlq]/mov/gm;
$code =~ s/movzb/movzx/gm;
$code =~ s/repret/DB\t0F3h,0C3h/gm;
$code =~ s/cmpl/cmp/gm;
$code =~ s/xorb/xor/gm;
} else {
$code =~ s/([QD]*WORD|BYTE)://gm;
$code =~ s/repret/.byte\t0xF3,0xC3/gm;
}
print $code;