Commit 96ec4abd authored by Andy Polyakov's avatar Andy Polyakov
Browse files

Eliminate ~3.5KB of duplicate code in des-586.pl and reserve for folded 

loop option, which can give further 3KB code reduction.
parent 70532b7d

crypto/des/asm/des-586.pl

+89 −32
Original line number Diff line number Diff line
@@ -18,8 +18,14 @@ require "desboth.pl"; 


$L="edi";

$R="esi";

$trans="ebp";

$small_footprint=1 if (grep(/\-DOPENSSL_SMALL_FOOTPRINT/,@ARGV));

# one can discuss setting this variable to 1 unconditionally, as

# the folded loop is only 3% slower than unrolled, but >7 times smaller



&external_label("DES_SPtrans");

&DES_encrypt_internal();

&DES_decrypt_internal();

&DES_encrypt("DES_encrypt1",1);

&DES_encrypt("DES_encrypt2",0);

&DES_encrypt3("DES_encrypt3",1);
@@ -30,6 +36,80 @@ $R="esi"; 


&asm_finish();



sub DES_encrypt_internal()

	{

	&function_begin_B("_x86_DES_encrypt");



	if ($small_footprint)

	    {

	    &lea("edx",&DWP(128,"ecx"));

	    &push("edx");

	    &push("ecx");

	    &set_label("eloop");

		&D_ENCRYPT(0,$L,$R,0,$trans,"eax","ebx","ecx","edx",&swtmp(0));

		&comment("");

		&D_ENCRYPT(1,$R,$L,2,$trans,"eax","ebx","ecx","edx",&swtmp(0));

		&comment("");

		&add("ecx",16);

		&cmp("ecx",&swtmp(1));

		&mov(&swtmp(0),"ecx");

		&jb(&label("eloop"));

	    &add("esp",8);

	    }

	else

	    {

	    &push("ecx");

	    for ($i=0; $i<16; $i+=2)

		{

		&comment("Round $i");

		&D_ENCRYPT($i,$L,$R,$i*2,$trans,"eax","ebx","ecx","edx",&swtmp(0));

		&comment("Round ".sprintf("%d",$i+1));

		&D_ENCRYPT($i+1,$R,$L,($i+1)*2,$trans,"eax","ebx","ecx","edx",&swtmp(0));

		}

	    &add("esp",4);

	}

	&ret();



	&function_end_B("_x86_DES_encrypt");

	}

	

sub DES_decrypt_internal()

	{

	&function_begin_B("_x86_DES_decrypt");



	if ($small_footprint)

	    {

	    &push("ecx");

	    &lea("ecx",&DWP(128,"ecx"));

	    &push("ecx");

	    &set_label("dloop");

		&D_ENCRYPT(0,$L,$R,-2,$trans,"eax","ebx","ecx","edx",&swtmp(0));

		&comment("");

		&D_ENCRYPT(1,$R,$L,-4,$trans,"eax","ebx","ecx","edx",&swtmp(0));

		&comment("");

		&sub("ecx",16);

		&cmp("ecx",&swtmp(1));

		&mov(&swtmp(0),"ecx");

		&ja(&label("dloop"));

	    &add("esp",8);

	    }

	else

	    {

	    &push("ecx");

	    for ($i=15; $i>0; $i-=2)

		{

		&comment("Round $i");

		&D_ENCRYPT(15-$i,$L,$R,$i*2,$trans,"eax","ebx","ecx","edx",&swtmp(0));

		&comment("Round ".sprintf("%d",$i-1));

		&D_ENCRYPT(15-$i+1,$R,$L,($i-1)*2,$trans,"eax","ebx","ecx","edx",&swtmp(0));

		}

	    &add("esp",4);

	    }

	&ret();



	&function_end_B("_x86_DES_decrypt");

	}

	

sub DES_encrypt

	{

	local($name,$do_ip)=@_;
@@ -41,7 +121,6 @@ sub DES_encrypt 


	&comment("");

	&comment("Load the 2 words");

	$trans="ebp";



	if ($do_ip)

		{
@@ -75,38 +154,16 @@ sub DES_encrypt 


	# PIC-ification:-)

	&picmeup($trans,"DES_SPtrans");

	#if ($cpp)	{ &picmeup($trans,"DES_SPtrans");   }

	#else		{ &lea($trans,&DWP("DES_SPtrans")); }



	&mov(	"ecx",	&wparam(1)	);

	&cmp("ebx","0");

	&je(&label("start_decrypt"));



	for ($i=0; $i<16; $i+=2)

		{

		&comment("");

		&comment("Round $i");

		&D_ENCRYPT($i,$L,$R,$i*2,$trans,"eax","ebx","ecx","edx");



		&comment("");

		&comment("Round ".sprintf("%d",$i+1));

		&D_ENCRYPT($i+1,$R,$L,($i+1)*2,$trans,"eax","ebx","ecx","edx");

		}

	&jmp(&label("end"));



	&set_label("start_decrypt");



	for ($i=15; $i>0; $i-=2)

		{

		&comment("");

		&comment("Round $i");

		&D_ENCRYPT(15-$i,$L,$R,$i*2,$trans,"eax","ebx","ecx","edx");

		&comment("");

		&comment("Round ".sprintf("%d",$i-1));

		&D_ENCRYPT(15-$i+1,$R,$L,($i-1)*2,$trans,"eax","ebx","ecx","edx");

		}



	&set_label("end");

	&cmp("ebx","0");

	&je(&label("decrypt"));

	&call("_x86_DES_encrypt");

	&jmp(&label("done"));

	&set_label("decrypt");

	&call("_x86_DES_decrypt");

	&set_label("done");



	if ($do_ip)

		{
@@ -140,7 +197,7 @@ sub DES_encrypt 


sub D_ENCRYPT

	{

	local($r,$L,$R,$S,$trans,$u,$tmp1,$tmp2,$t)=@_;

	local($r,$L,$R,$S,$trans,$u,$tmp1,$tmp2,$t,$wp1)=@_;



	 &mov(	$u,		&DWP(&n2a($S*4),$tmp2,"",0));

	&xor(	$tmp1,		$tmp1);
@@ -167,7 +224,7 @@ sub D_ENCRYPT 
	&and(	$t,		"0xff"	);

	 &xor(	$L,		&DWP("0x600",$trans,$tmp1,0));

	 &xor(	$L,		&DWP("0x700",$trans,$tmp2,0));

	&mov(	$tmp2,		&wparam(1)	);

	&mov(	$tmp2,		$wp1	);

	 &xor(	$L,		&DWP("0x400",$trans,$u,0));

	 &xor(	$L,		&DWP("0x500",$trans,$t,0));

	}