Commit 1809e858 authored by Andy Polyakov's avatar Andy Polyakov
Browse files

Eliminate compiler warnings and throw in performance table.

parent 2bbc970e

crypto/bn/asm/x86_64-gcc.c

+34 −16
Original line number Diff line number Diff line
@@ -13,20 +13,42 @@ 
 * A. Well, that's because this code is basically a quick-n-dirty

 *    proof-of-concept hack. As you can see it's implemented with

 *    inline assembler, which means that you're bound to GCC and that

 *    there must be a room for fine-tuning.

 *    there might be enough room for further improvement.

 *

 * Q. Why inline assembler?

 * A. x86_64 features own ABI I'm not familiar with. Which is why

 *    I decided to let the compiler take care of subroutine

 *    prologue/epilogue as well as register allocation.

 * A. x86_64 features own ABI which I'm not familiar with. This is

 *    why I decided to let the compiler take care of subroutine

 *    prologue/epilogue as well as register allocation. For reference.

 *    Win64 implements different ABI for AMD64, different from Linux.

 *

 * Q. How much faster does it get?

 * A. Unfortunately people sitting on x86_64 hardware are prohibited

 *    to disclose the performance numbers, so they (SuSE labs to be

 *    specific) wouldn't tell me. However! Very similar coding technique

 *    (reaching out for 128-bit result from 64x64-bit multiplication)

 *    results in >3 times performance improvement on MIPS and I see no

 *    reason why gain on x86_64 would be so much different:-)

 * A. 'apps/openssl speed rsa dsa' output with no-asm:

 *

 *	                  sign    verify    sign/s verify/s

 *	rsa  512 bits   0.0006s   0.0001s   1683.8  18456.2

 *	rsa 1024 bits   0.0028s   0.0002s    356.0   6407.0

 *	rsa 2048 bits   0.0172s   0.0005s     58.0   1957.8

 *	rsa 4096 bits   0.1155s   0.0018s      8.7    555.6

 *	                  sign    verify    sign/s verify/s

 *	dsa  512 bits   0.0005s   0.0006s   2100.8   1768.3

 *	dsa 1024 bits   0.0014s   0.0018s    692.3    559.2

 *	dsa 2048 bits   0.0049s   0.0061s    204.7    165.0

 *

 *    'apps/openssl speed rsa dsa' output with this module:

 *

 *	                  sign    verify    sign/s verify/s

 *	rsa  512 bits   0.0004s   0.0000s   2767.1  33297.9

 *	rsa 1024 bits   0.0012s   0.0001s    867.4  14674.7

 *	rsa 2048 bits   0.0061s   0.0002s    164.0   5270.0

 *	rsa 4096 bits   0.0384s   0.0006s     26.1   1650.8

 *	                  sign    verify    sign/s verify/s

 *	dsa  512 bits   0.0002s   0.0003s   4442.2   3786.3

 *	dsa 1024 bits   0.0005s   0.0007s   1835.1   1497.4

 *	dsa 2048 bits   0.0016s   0.0020s    620.4    504.6

 *

 *    For the reference. IA-32 assembler implementation performs

 *    very much like 64-bit code compiled with no-asm on the same

 *    machine.

 */



#define BN_ULONG unsigned long
@@ -151,7 +173,7 @@ BN_ULONG bn_div_words(BN_ULONG h, BN_ULONG l, BN_ULONG d) 
}



BN_ULONG bn_add_words (BN_ULONG *rp, BN_ULONG *ap, BN_ULONG *bp,int n)

{ BN_ULONG ret,i;

{ BN_ULONG ret=0,i=0;



	if (n <= 0) return 0;
@@ -174,7 +196,7 @@ BN_ULONG bn_add_words (BN_ULONG *rp, BN_ULONG *ap, BN_ULONG *bp,int n) 


#ifndef SIMICS

BN_ULONG bn_sub_words (BN_ULONG *rp, BN_ULONG *ap, BN_ULONG *bp,int n)

{ BN_ULONG ret,i;

{ BN_ULONG ret=0,i=0;



	if (n <= 0) return 0;
@@ -318,7 +340,6 @@ BN_ULONG bn_sub_words(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n) 


void bn_mul_comba8(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)

	{

	BN_ULONG bl,bh;

	BN_ULONG t1,t2;

	BN_ULONG c1,c2,c3;
@@ -423,7 +444,6 @@ void bn_mul_comba8(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b) 


void bn_mul_comba4(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)

	{

	BN_ULONG bl,bh;

	BN_ULONG t1,t2;

	BN_ULONG c1,c2,c3;
@@ -464,7 +484,6 @@ void bn_mul_comba4(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b) 


void bn_sqr_comba8(BN_ULONG *r, BN_ULONG *a)

	{

	BN_ULONG bl,bh;

	BN_ULONG t1,t2;

	BN_ULONG c1,c2,c3;
@@ -541,7 +560,6 @@ void bn_sqr_comba8(BN_ULONG *r, BN_ULONG *a) 


void bn_sqr_comba4(BN_ULONG *r, BN_ULONG *a)

	{

	BN_ULONG bl,bh;

	BN_ULONG t1,t2;

	BN_ULONG c1,c2,c3;