#! /usr/bin/env perl

# Copyright 2007-2016 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

package x86gas;

*out=\@::out;

$::lbdecor=$::aout?"L":".L";		# local label decoration

$nmdecor=($::aout or $::coff)?"_":"";	# external name decoration

$initseg="";

$align=16;

$align=log($align)/log(2) if ($::aout);

$com_start="#" if ($::aout or $::coff);

sub opsize()

{ my $reg=shift;

    if    ($reg =~ m/^%e/o)		{ "l"; }

    elsif ($reg =~ m/^%[a-d][hl]$/o)	{ "b"; }

    elsif ($reg =~ m/^%[yxm]/o)		{ undef; }

    else				{ "w"; }

}

# swap arguments;

# expand opcode with size suffix;

# prefix numeric constants with $;

sub ::generic

{ my($opcode,@arg)=@_;

  my($suffix,$dst,$src);

    @arg=reverse(@arg);

    for (@arg)

    {	s/^(\*?)(e?[a-dsixphl]{2})$/$1%$2/o;	# gp registers

	s/^([xy]?mm[0-7])$/%$1/o;		# xmm/mmx registers

	s/^(\-?[0-9]+)$/\$$1/o;			# constants

	s/^(\-?0x[0-9a-f]+)$/\$$1/o;		# constants

    }

    $dst = $arg[$#arg]		if ($#arg>=0);

    $src = $arg[$#arg-1]	if ($#arg>=1);

    if    ($dst =~ m/^%/o)	{ $suffix=&opsize($dst); }

    elsif ($src =~ m/^%/o)	{ $suffix=&opsize($src); }

    else			{ $suffix="l";           }

    undef $suffix if ($dst =~ m/^%[xm]/o || $src =~ m/^%[xm]/o);

    if ($#_==0)				{ &::emit($opcode);		}

    elsif ($#_==1 && $opcode =~ m/^(call|clflush|j|loop|set)/o)

					{ &::emit($opcode,@arg);	}

    else				{ &::emit($opcode.$suffix,@arg);}

  1;

}

#

# opcodes not covered by ::generic above, mostly inconsistent namings...

#

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

sub ::pushfd	{ &::pushfl;			}

sub ::popfd	{ &::popfl;			}

sub ::cpuid	{ &::emit(".byte\t0x0f,0xa2");	}

sub ::rdtsc	{ &::emit(".byte\t0x0f,0x31");	}

sub ::call	{ &::emit("call",(&::islabel($_[0]) or "$nmdecor$_[0]")); }

sub ::call_ptr	{ &::generic("call","*$_[0]");	}

sub ::jmp_ptr	{ &::generic("jmp","*$_[0]");	}

*::bswap = sub	{ &::emit("bswap","%$_[0]");	} if (!$::i386);

sub ::DWP

{ my($addr,$reg1,$reg2,$idx)=@_;

  my $ret="";

    if (!defined($idx) && 1*$reg2) { $idx=$reg2; $reg2=$reg1; undef $reg1; }

    $addr =~ s/^\s+//;

    # prepend global references with optional underscore

    $addr =~ s/^([^\+\-0-9][^\+\-]*)/&::islabel($1) or "$nmdecor$1"/ige;

    $reg1 = "%$reg1" if ($reg1);

    $reg2 = "%$reg2" if ($reg2);

    $ret .= $addr if (($addr ne "") && ($addr ne 0));

    if ($reg2)

    {	$idx!= 0 or $idx=1;

	$ret .= "($reg1,$reg2,$idx)";

    }

    elsif ($reg1)

    {	$ret .= "($reg1)";	}

  $ret;

}

sub ::QWP	{ &::DWP(@_);	}

sub ::BP	{ &::DWP(@_);	}

sub ::WP	{ &::DWP(@_);	}

sub ::BC	{ @_;		}

sub ::DWC	{ @_;		}

sub ::file

{   push(@out,".text\n");	}

sub ::function_begin_B

{ my $func=shift;

  my $global=($func !~ /^_/);

  my $begin="${::lbdecor}_${func}_begin";

    &::LABEL($func,$global?"$begin":"$nmdecor$func");

    $func=$nmdecor.$func;

    push(@out,".globl\t$func\n")	if ($global);

    if ($::coff)

    {	push(@out,".def\t$func;\t.scl\t".(3-$global).";\t.type\t32;\t.endef\n"); }

    elsif (($::aout and !$::pic) or $::macosx)

    { }

    else

    {	push(@out,".type	$func,\@function\n"); }

    push(@out,".align\t$align\n");

    push(@out,"$func:\n");

    push(@out,"$begin:\n")		if ($global);

    &::endbranch();

    $::stack=4;

}

sub ::function_end_B

{ my $func=shift;

    push(@out,".size\t$nmdecor$func,.-".&::LABEL($func)."\n") if ($::elf);

    $::stack=0;

    &::wipe_labels();

}

sub ::comment

	{

	if (!defined($com_start) or $::elf)

		{	# Regarding $::elf above...

			# GNU and SVR4 as'es use different comment delimiters,

		push(@out,"\n");	# so we just skip ELF comments...

		return;

		}

	foreach (@_)

		{

		if (/^\s*$/)

			{ push(@out,"\n"); }

		else

			{ push(@out,"\t$com_start $_ $com_end\n"); }

		}

	}

sub ::external_label

{   foreach(@_) { &::LABEL($_,$nmdecor.$_); }   }

sub ::public_label

{   push(@out,".globl\t".&::LABEL($_[0],$nmdecor.$_[0])."\n");   }

sub ::file_end

{   if ($::macosx)

    {	if (%non_lazy_ptr)

    	{   push(@out,".section __IMPORT,__pointers,non_lazy_symbol_pointers\n");

	    foreach $i (keys %non_lazy_ptr)

	    {	push(@out,"$non_lazy_ptr{$i}:\n.indirect_symbol\t$i\n.long\t0\n");   }

	}

    }

    if (grep {/\b${nmdecor}OPENSSL_ia32cap_P\b/i} @out) {

	my $tmp=".comm\t${nmdecor}OPENSSL_ia32cap_P,16";

	if ($::macosx)	{ push (@out,"$tmp,2\n"); }

	elsif ($::elf)	{ push (@out,"$tmp,4\n"); }

	else		{ push (@out,"$tmp\n"); }

    }

    push(@out,$initseg) if ($initseg);

    if ($::elf) {

	push(@out,"

	.section \".note.gnu.property\", \"a\"

	.p2align 2

	.long 1f - 0f

	.long 4f - 1f

	.long 5

0:

	.asciz \"GNU\"

1:

	.p2align 2

	.long 0xc0000002

	.long 3f - 2f

2:

	.long 3

3:

	.p2align 2

4:

");

    }

}

sub ::data_byte	{   push(@out,".byte\t".join(',',@_)."\n");   }

sub ::data_short{   push(@out,".value\t".join(',',@_)."\n");  }

sub ::data_word {   push(@out,".long\t".join(',',@_)."\n");   }

sub ::align

{ my $val=$_[0];

    if ($::aout)

    {	$val=int(log($val)/log(2));

	$val.=",0x90";

    }

    push(@out,".align\t$val\n");

}

sub ::picmeup

{ my($dst,$sym,$base,$reflabel)=@_;

    if (($::pic && ($::elf || $::aout)) || $::macosx)

    {	if (!defined($base))

	{   &::call(&::label("PIC_me_up"));

	    &::set_label("PIC_me_up");

	    &::blindpop($dst);

	    $base=$dst;

	    $reflabel=&::label("PIC_me_up");

	}

	if ($::macosx)

	{   my $indirect=&::static_label("$nmdecor$sym\$non_lazy_ptr");

	    &::mov($dst,&::DWP("$indirect-$reflabel",$base));

	    $non_lazy_ptr{"$nmdecor$sym"}=$indirect;

	}

	elsif ($sym eq "OPENSSL_ia32cap_P" && $::elf>0)

	{   &::lea($dst,&::DWP("$sym-$reflabel",$base));   }

	else

	{   &::lea($dst,&::DWP("_GLOBAL_OFFSET_TABLE_+[.-$reflabel]",

			    $base));

	    &::mov($dst,&::DWP("$sym\@GOT",$dst));

	}

    }

    else

    {	&::lea($dst,&::DWP($sym));	}

}

sub ::initseg

{ my $f=$nmdecor.shift;

    if ($::android)

    {	$initseg.=<<___;

.section	.init_array

.align	4

.long	$f

___

    }

    elsif ($::elf)

    {	$initseg.=<<___;

.section	.init

	call	$f

___

    }

    elsif ($::coff)

    {   $initseg.=<<___;	# applies to both Cygwin and Mingw

.section	.ctors

.long	$f

___

    }

    elsif ($::macosx)

    {	$initseg.=<<___;

.mod_init_func

.align 2

.long   $f

___

    }

    elsif ($::aout)

    {	my $ctor="${nmdecor}_GLOBAL_\$I\$$f";

	$initseg.=".text\n";

	$initseg.=".type	$ctor,\@function\n" if ($::pic);

	$initseg.=<<___;	# OpenBSD way...

.globl	$ctor

.align	2

$ctor:

	jmp	$f

___

    }

}

sub ::dataseg

{   push(@out,".data\n");   }

*::hidden = sub { push(@out,".hidden\t$nmdecor$_[0]\n"); } if ($::elf);

1;