#! /usr/bin/env perl

# Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.

#

# Licensed under the OpenSSL license (the "License").  You may not use

# this file except in compliance with the License.  You can obtain a copy

# in the file LICENSE in the source distribution or at

# https://www.openssl.org/source/license.html

# require 'x86asm.pl';

# &asm_init(<flavor>[,$i386only]);

# &function_begin("foo");

# ...

# &function_end("foo");

# &asm_finish

$out=();

$i386=0;

# AUTOLOAD is this context has quite unpleasant side effect, namely

# that typos in function calls effectively go to assembler output,

# but on the pros side we don't have to implement one subroutine per

# each opcode...

sub ::AUTOLOAD

{ my $opcode = $AUTOLOAD;

    die "more than 4 arguments passed to $opcode" if ($#_>3);

    $opcode =~ s/.*:://;

    if    ($opcode =~ /^push/) { $stack+=4; }

    elsif ($opcode =~ /^pop/)  { $stack-=4; }

    &generic($opcode,@_) or die "undefined subroutine \&$AUTOLOAD";

}

sub ::emit

{ my $opcode=shift;

    if ($#_==-1)    { push(@out,"\t$opcode\n");				}

    else            { push(@out,"\t$opcode\t".join(',',@_)."\n");	}

}

sub ::LB

{   $_[0] =~ m/^e?([a-d])x$/o or die "$_[0] does not have a 'low byte'";

  $1."l";

}

sub ::HB

{   $_[0] =~ m/^e?([a-d])x$/o or die "$_[0] does not have a 'high byte'";

  $1."h";

}

sub ::stack_push{ my $num=$_[0]*4; $stack+=$num; &sub("esp",$num);	}

sub ::stack_pop	{ my $num=$_[0]*4; $stack-=$num; &add("esp",$num);	}

sub ::blindpop	{ &pop($_[0]); $stack+=4;				}

sub ::wparam	{ &DWP($stack+4*$_[0],"esp");				}

sub ::swtmp	{ &DWP(4*$_[0],"esp");					}

sub ::bswap

{   if ($i386)	# emulate bswap for i386

    {	&comment("bswap @_");

	&xchg(&HB(@_),&LB(@_));

	&ror (@_,16);

	&xchg(&HB(@_),&LB(@_));

    }

    else

    {	&generic("bswap",@_);	}

}

# These are made-up opcodes introduced over the years essentially

# by ignorance, just alias them to real ones...

sub ::movb	{ &mov(@_);	}

sub ::xorb	{ &xor(@_);	}

sub ::rotl	{ &rol(@_);	}

sub ::rotr	{ &ror(@_);	}

sub ::exch	{ &xchg(@_);	}

sub ::halt	{ &hl;;		}

sub ::movz	{ &movzx(@_);	}

sub ::pushf	{ &pushfd;	}

sub ::popf	{ &popfd;	}

# 3 argument instructions

sub ::movq

{ my($p1,$p2,$optimize)=@_;

    if ($optimize && $p1=~/^mm[0-7]$/ && $p2=~/^mm[0-7]$/)

    # movq between mmx registers can sink Intel CPUs

    {	&::pshufw($p1,$p2,0xe4);		}

    else

    {	&::generic("movq",@_);			}

}

# SSE>2 instructions

my %regrm = (	"eax"=>0, "ecx"=>1, "edx"=>2, "ebx"=>3,

		"esp"=>4, "ebp"=>5, "esi"=>6, "edi"=>7	);

sub ::pextrd

{ my($dst,$src,$imm)=@_;

    if ("$dst:$src" =~ /(e[a-dsd][ixp]):xmm([0-7])/)

    {	&::data_byte(0x66,0x0f,0x3a,0x16,0xc0|($2<<3)|$regrm{$1},$imm);	}

    else

    {	&::generic("pextrd",@_);		}

}

sub ::pinsrd

{ my($dst,$src,$imm)=@_;

    if ("$dst:$src" =~ /xmm([0-7]):(e[a-dsd][ixp])/)

    {	&::data_byte(0x66,0x0f,0x3a,0x22,0xc0|($1<<3)|$regrm{$2},$imm);	}

    else

    {	&::generic("pinsrd",@_);		}

}

sub ::pshufb

{ my($dst,$src)=@_;

    if ("$dst:$src" =~ /xmm([0-7]):xmm([0-7])/)

    {	&data_byte(0x66,0x0f,0x38,0x00,0xc0|($1<<3)|$2);	}

    else

    {	&::generic("pshufb",@_);		}

}

sub ::palignr

{ my($dst,$src,$imm)=@_;

    if ("$dst:$src" =~ /xmm([0-7]):xmm([0-7])/)

    {	&::data_byte(0x66,0x0f,0x3a,0x0f,0xc0|($1<<3)|$2,$imm);	}

    else

    {	&::generic("palignr",@_);		}

}

sub ::pclmulqdq

{ my($dst,$src,$imm)=@_;

    if ("$dst:$src" =~ /xmm([0-7]):xmm([0-7])/)

    {	&::data_byte(0x66,0x0f,0x3a,0x44,0xc0|($1<<3)|$2,$imm);	}

    else

    {	&::generic("pclmulqdq",@_);		}

}

sub ::rdrand

{ my ($dst)=@_;

    if ($dst =~ /(e[a-dsd][ixp])/)

    {	&::data_byte(0x0f,0xc7,0xf0|$regrm{$dst});	}

    else

    {	&::generic("rdrand",@_);	}

}

sub ::rdseed

{ my ($dst)=@_;

    if ($dst =~ /(e[a-dsd][ixp])/)

    {	&::data_byte(0x0f,0xc7,0xf8|$regrm{$dst});	}

    else

    {	&::generic("rdrand",@_);	}

}

sub rxb {

 local *opcode=shift;

 my ($dst,$src1,$src2,$rxb)=@_;

   $rxb|=0x7<<5;

   $rxb&=~(0x04<<5) if($dst>=8);

   $rxb&=~(0x01<<5) if($src1>=8);

   $rxb&=~(0x02<<5) if($src2>=8);

   push @opcode,$rxb;

}

sub ::vprotd

{ my $args=join(',',@_);

    if ($args =~ /xmm([0-7]),xmm([0-7]),([x0-9a-f]+)/)

    { my @opcode=(0x8f);

	rxb(\@opcode,$1,$2,-1,0x08);

	push @opcode,0x78,0xc2;

	push @opcode,0xc0|($2&7)|(($1&7)<<3);		# ModR/M

	my $c=$3;

	push @opcode,$c=~/^0/?oct($c):$c;

	&::data_byte(@opcode);

    }

    else

    {	&::generic("vprotd",@_);	}

}

sub ::endbranch

{

    &::data_byte(0xf3,0x0f,0x1e,0xfb);

}

# label management

$lbdecor="L";		# local label decoration, set by package

$label="000";

sub ::islabel		# see is argument is a known label

{ my $i;

    foreach $i (values %label) { return $i if ($i eq $_[0]); }

  $label{$_[0]};	# can be undef

}

sub ::label		# instantiate a function-scope label

{   if (!defined($label{$_[0]}))

    {	$label{$_[0]}="${lbdecor}${label}${_[0]}"; $label++;   }

  $label{$_[0]};

}

sub ::LABEL		# instantiate a file-scope label

{   $label{$_[0]}=$_[1] if (!defined($label{$_[0]}));

  $label{$_[0]};

}

sub ::static_label	{ &::LABEL($_[0],$lbdecor.$_[0]); }

sub ::set_label_B	{ push(@out,"@_:\n"); }

sub ::set_label

{ my $label=&::label($_[0]);

    &::align($_[1]) if ($_[1]>1);

    &::set_label_B($label);

  $label;

}

sub ::wipe_labels	# wipes function-scope labels

{   foreach $i (keys %label)

    {	delete $label{$i} if ($label{$i} =~ /^\Q${lbdecor}\E[0-9]{3}/);	}

}

# subroutine management

sub ::function_begin

{   &function_begin_B(@_);

    $stack=4;

    &push("ebp");

    &push("ebx");

    &push("esi");

    &push("edi");

}

sub ::function_end

{   &pop("edi");

    &pop("esi");

    &pop("ebx");

    &pop("ebp");

    &ret();

    &function_end_B(@_);

    $stack=0;

    &wipe_labels();

}

sub ::function_end_A

{   &pop("edi");

    &pop("esi");

    &pop("ebx");

    &pop("ebp");

    &ret();

    $stack+=16;	# readjust esp as if we didn't pop anything

}

sub ::asciz

{ my @str=unpack("C*",shift);

    push @str,0;

    while ($#str>15) {

	&data_byte(@str[0..15]);

	foreach (0..15) { shift @str; }

    }

    &data_byte(@str) if (@str);

}

sub ::asm_finish

{   &file_end();

    print @out;

}

sub ::asm_init

{ my ($type,$cpu)=@_;

    $i386=$cpu;

    $elf=$cpp=$coff=$aout=$macosx=$win32=$mwerks=$android=0;

    if    (($type eq "elf"))

    {	$elf=1;			require "x86gas.pl";	}

    elsif (($type eq "elf-1"))

    {	$elf=-1;		require "x86gas.pl";	}

    elsif (($type eq "a\.out"))

    {	$aout=1;		require "x86gas.pl";	}

    elsif (($type eq "coff" or $type eq "gaswin"))

    {	$coff=1;		require "x86gas.pl";	}

    elsif (($type eq "win32n"))

    {	$win32=1;		require "x86nasm.pl";	}

    elsif (($type eq "win32"))

    {	$win32=1;		require "x86masm.pl";	}

    elsif (($type eq "macosx"))

    {	$aout=1; $macosx=1;	require "x86gas.pl";	}

    elsif (($type eq "android"))

    {	$elf=1; $android=1;	require "x86gas.pl";	}

    else

    {	print STDERR <<"EOF";

Pick one target type from

	elf	- Linux, FreeBSD, Solaris x86, etc.

	a.out	- DJGPP, elder OpenBSD, etc.

	coff	- GAS/COFF such as Win32 targets

	win32n	- Windows 95/Windows NT NASM format

	macosx	- Mac OS X

EOF

	exit(1);

    }

    $pic=0;

    for (@ARGV) { $pic=1 if (/\-[fK]PIC/i); }

    &file();

}

sub ::hidden {}

1;