openssl/crypto/bn/asm/armv4-gf2m.pl
Andy Polyakov 11208dcfb9 ARMv4 assembly pack: implement support for Thumb2.
As some of ARM processors, more specifically Cortex-Mx series, are
Thumb2-only, we need to support Thumb2-only builds even in assembly.

Reviewed-by: Tim Hudson <tjh@openssl.org>
2015-09-25 13:34:02 +02:00

325 lines
7.9 KiB
Prolog

#!/usr/bin/env perl
#
# ====================================================================
# Written by Andy Polyakov <appro@openssl.org> for the OpenSSL
# project. The module is, however, dual licensed under OpenSSL and
# CRYPTOGAMS licenses depending on where you obtain it. For further
# details see http://www.openssl.org/~appro/cryptogams/.
# ====================================================================
#
# May 2011
#
# The module implements bn_GF2m_mul_2x2 polynomial multiplication
# used in bn_gf2m.c. It's kind of low-hanging mechanical port from
# C for the time being... Except that it has two code paths: pure
# integer code suitable for any ARMv4 and later CPU and NEON code
# suitable for ARMv7. Pure integer 1x1 multiplication subroutine runs
# in ~45 cycles on dual-issue core such as Cortex A8, which is ~50%
# faster than compiler-generated code. For ECDH and ECDSA verify (but
# not for ECDSA sign) it means 25%-45% improvement depending on key
# length, more for longer keys. Even though NEON 1x1 multiplication
# runs in even less cycles, ~30, improvement is measurable only on
# longer keys. One has to optimize code elsewhere to get NEON glow...
#
# April 2014
#
# Double bn_GF2m_mul_2x2 performance by using algorithm from paper
# referred below, which improves ECDH and ECDSA verify benchmarks
# by 18-40%.
#
# Câmara, D.; Gouvêa, C. P. L.; López, J. & Dahab, R.: Fast Software
# Polynomial Multiplication on ARM Processors using the NEON Engine.
#
# http://conradoplg.cryptoland.net/files/2010/12/mocrysen13.pdf
$flavour = shift;
if ($flavour=~/^\w[\w\-]*\.\w+$/) { $output=$flavour; undef $flavour; }
else { while (($output=shift) && ($output!~/^\w[\w\-]*\.\w+$/)) {} }
if ($flavour && $flavour ne "void") {
$0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
( $xlate="${dir}arm-xlate.pl" and -f $xlate ) or
( $xlate="${dir}../../perlasm/arm-xlate.pl" and -f $xlate) or
die "can't locate arm-xlate.pl";
open STDOUT,"| \"$^X\" $xlate $flavour $output";
} else {
open STDOUT,">$output";
}
$code=<<___;
#include "arm_arch.h"
.text
#if defined(__thumb2__) && !defined(__APPLE__)
.syntax unified
.thumb
#else
.code 32
#endif
___
################
# private interface to mul_1x1_ialu
#
$a="r1";
$b="r0";
($a0,$a1,$a2,$a12,$a4,$a14)=
($hi,$lo,$t0,$t1, $i0,$i1 )=map("r$_",(4..9),12);
$mask="r12";
$code.=<<___;
.type mul_1x1_ialu,%function
.align 5
mul_1x1_ialu:
mov $a0,#0
bic $a1,$a,#3<<30 @ a1=a&0x3fffffff
str $a0,[sp,#0] @ tab[0]=0
add $a2,$a1,$a1 @ a2=a1<<1
str $a1,[sp,#4] @ tab[1]=a1
eor $a12,$a1,$a2 @ a1^a2
str $a2,[sp,#8] @ tab[2]=a2
mov $a4,$a1,lsl#2 @ a4=a1<<2
str $a12,[sp,#12] @ tab[3]=a1^a2
eor $a14,$a1,$a4 @ a1^a4
str $a4,[sp,#16] @ tab[4]=a4
eor $a0,$a2,$a4 @ a2^a4
str $a14,[sp,#20] @ tab[5]=a1^a4
eor $a12,$a12,$a4 @ a1^a2^a4
str $a0,[sp,#24] @ tab[6]=a2^a4
and $i0,$mask,$b,lsl#2
str $a12,[sp,#28] @ tab[7]=a1^a2^a4
and $i1,$mask,$b,lsr#1
ldr $lo,[sp,$i0] @ tab[b & 0x7]
and $i0,$mask,$b,lsr#4
ldr $t1,[sp,$i1] @ tab[b >> 3 & 0x7]
and $i1,$mask,$b,lsr#7
ldr $t0,[sp,$i0] @ tab[b >> 6 & 0x7]
eor $lo,$lo,$t1,lsl#3 @ stall
mov $hi,$t1,lsr#29
ldr $t1,[sp,$i1] @ tab[b >> 9 & 0x7]
and $i0,$mask,$b,lsr#10
eor $lo,$lo,$t0,lsl#6
eor $hi,$hi,$t0,lsr#26
ldr $t0,[sp,$i0] @ tab[b >> 12 & 0x7]
and $i1,$mask,$b,lsr#13
eor $lo,$lo,$t1,lsl#9
eor $hi,$hi,$t1,lsr#23
ldr $t1,[sp,$i1] @ tab[b >> 15 & 0x7]
and $i0,$mask,$b,lsr#16
eor $lo,$lo,$t0,lsl#12
eor $hi,$hi,$t0,lsr#20
ldr $t0,[sp,$i0] @ tab[b >> 18 & 0x7]
and $i1,$mask,$b,lsr#19
eor $lo,$lo,$t1,lsl#15
eor $hi,$hi,$t1,lsr#17
ldr $t1,[sp,$i1] @ tab[b >> 21 & 0x7]
and $i0,$mask,$b,lsr#22
eor $lo,$lo,$t0,lsl#18
eor $hi,$hi,$t0,lsr#14
ldr $t0,[sp,$i0] @ tab[b >> 24 & 0x7]
and $i1,$mask,$b,lsr#25
eor $lo,$lo,$t1,lsl#21
eor $hi,$hi,$t1,lsr#11
ldr $t1,[sp,$i1] @ tab[b >> 27 & 0x7]
tst $a,#1<<30
and $i0,$mask,$b,lsr#28
eor $lo,$lo,$t0,lsl#24
eor $hi,$hi,$t0,lsr#8
ldr $t0,[sp,$i0] @ tab[b >> 30 ]
#ifdef __thumb2__
itt ne
#endif
eorne $lo,$lo,$b,lsl#30
eorne $hi,$hi,$b,lsr#2
tst $a,#1<<31
eor $lo,$lo,$t1,lsl#27
eor $hi,$hi,$t1,lsr#5
#ifdef __thumb2__
itt ne
#endif
eorne $lo,$lo,$b,lsl#31
eorne $hi,$hi,$b,lsr#1
eor $lo,$lo,$t0,lsl#30
eor $hi,$hi,$t0,lsr#2
mov pc,lr
.size mul_1x1_ialu,.-mul_1x1_ialu
___
################
# void bn_GF2m_mul_2x2(BN_ULONG *r,
# BN_ULONG a1,BN_ULONG a0,
# BN_ULONG b1,BN_ULONG b0); # r[3..0]=a1a0·b1b0
{
$code.=<<___;
.global bn_GF2m_mul_2x2
.type bn_GF2m_mul_2x2,%function
.align 5
bn_GF2m_mul_2x2:
#if __ARM_MAX_ARCH__>=7
stmdb sp!,{r10,lr}
ldr r12,.LOPENSSL_armcap
adr r10,.LOPENSSL_armcap
ldr r12,[r12,r10]
#ifdef __APPLE__
ldr r12,[r12]
#endif
tst r12,#ARMV7_NEON
itt ne
ldrne r10,[sp],#8
bne .LNEON
stmdb sp!,{r4-r9}
#else
stmdb sp!,{r4-r10,lr}
#endif
___
$ret="r10"; # reassigned 1st argument
$code.=<<___;
mov $ret,r0 @ reassign 1st argument
mov $b,r3 @ $b=b1
sub r7,sp,#36
mov r8,sp
and r7,r7,#-32
ldr r3,[sp,#32] @ load b0
mov $mask,#7<<2
mov sp,r7 @ allocate tab[8]
str r8,[r7,#32]
bl mul_1x1_ialu @ a1·b1
str $lo,[$ret,#8]
str $hi,[$ret,#12]
eor $b,$b,r3 @ flip b0 and b1
eor $a,$a,r2 @ flip a0 and a1
eor r3,r3,$b
eor r2,r2,$a
eor $b,$b,r3
eor $a,$a,r2
bl mul_1x1_ialu @ a0·b0
str $lo,[$ret]
str $hi,[$ret,#4]
eor $a,$a,r2
eor $b,$b,r3
bl mul_1x1_ialu @ (a1+a0)·(b1+b0)
___
@r=map("r$_",(6..9));
$code.=<<___;
ldmia $ret,{@r[0]-@r[3]}
eor $lo,$lo,$hi
ldr sp,[sp,#32] @ destroy tab[8]
eor $hi,$hi,@r[1]
eor $lo,$lo,@r[0]
eor $hi,$hi,@r[2]
eor $lo,$lo,@r[3]
eor $hi,$hi,@r[3]
str $hi,[$ret,#8]
eor $lo,$lo,$hi
str $lo,[$ret,#4]
#if __ARM_ARCH__>=5
ldmia sp!,{r4-r10,pc}
#else
ldmia sp!,{r4-r10,lr}
tst lr,#1
moveq pc,lr @ be binary compatible with V4, yet
bx lr @ interoperable with Thumb ISA:-)
#endif
___
}
{
my ($r,$t0,$t1,$t2,$t3)=map("q$_",(0..3,8..12));
my ($a,$b,$k48,$k32,$k16)=map("d$_",(26..31));
$code.=<<___;
#if __ARM_MAX_ARCH__>=7
.arch armv7-a
.fpu neon
.align 5
.LNEON:
ldr r12, [sp] @ 5th argument
vmov $a, r2, r1
vmov $b, r12, r3
vmov.i64 $k48, #0x0000ffffffffffff
vmov.i64 $k32, #0x00000000ffffffff
vmov.i64 $k16, #0x000000000000ffff
vext.8 $t0#lo, $a, $a, #1 @ A1
vmull.p8 $t0, $t0#lo, $b @ F = A1*B
vext.8 $r#lo, $b, $b, #1 @ B1
vmull.p8 $r, $a, $r#lo @ E = A*B1
vext.8 $t1#lo, $a, $a, #2 @ A2
vmull.p8 $t1, $t1#lo, $b @ H = A2*B
vext.8 $t3#lo, $b, $b, #2 @ B2
vmull.p8 $t3, $a, $t3#lo @ G = A*B2
vext.8 $t2#lo, $a, $a, #3 @ A3
veor $t0, $t0, $r @ L = E + F
vmull.p8 $t2, $t2#lo, $b @ J = A3*B
vext.8 $r#lo, $b, $b, #3 @ B3
veor $t1, $t1, $t3 @ M = G + H
vmull.p8 $r, $a, $r#lo @ I = A*B3
veor $t0#lo, $t0#lo, $t0#hi @ t0 = (L) (P0 + P1) << 8
vand $t0#hi, $t0#hi, $k48
vext.8 $t3#lo, $b, $b, #4 @ B4
veor $t1#lo, $t1#lo, $t1#hi @ t1 = (M) (P2 + P3) << 16
vand $t1#hi, $t1#hi, $k32
vmull.p8 $t3, $a, $t3#lo @ K = A*B4
veor $t2, $t2, $r @ N = I + J
veor $t0#lo, $t0#lo, $t0#hi
veor $t1#lo, $t1#lo, $t1#hi
veor $t2#lo, $t2#lo, $t2#hi @ t2 = (N) (P4 + P5) << 24
vand $t2#hi, $t2#hi, $k16
vext.8 $t0, $t0, $t0, #15
veor $t3#lo, $t3#lo, $t3#hi @ t3 = (K) (P6 + P7) << 32
vmov.i64 $t3#hi, #0
vext.8 $t1, $t1, $t1, #14
veor $t2#lo, $t2#lo, $t2#hi
vmull.p8 $r, $a, $b @ D = A*B
vext.8 $t3, $t3, $t3, #12
vext.8 $t2, $t2, $t2, #13
veor $t0, $t0, $t1
veor $t2, $t2, $t3
veor $r, $r, $t0
veor $r, $r, $t2
vst1.32 {$r}, [r0]
ret @ bx lr
#endif
___
}
$code.=<<___;
.size bn_GF2m_mul_2x2,.-bn_GF2m_mul_2x2
#if __ARM_MAX_ARCH__>=7
.align 5
.LOPENSSL_armcap:
.word OPENSSL_armcap_P-.
#endif
.asciz "GF(2^m) Multiplication for ARMv4/NEON, CRYPTOGAMS by <appro\@openssl.org>"
.align 5
#if __ARM_MAX_ARCH__>=7
.comm OPENSSL_armcap_P,4,4
#endif
___
foreach (split("\n",$code)) {
s/\`([^\`]*)\`/eval $1/geo;
s/\bq([0-9]+)#(lo|hi)/sprintf "d%d",2*$1+($2 eq "hi")/geo or
s/\bret\b/bx lr/go or
s/\bbx\s+lr\b/.word\t0xe12fff1e/go; # make it possible to compile with -march=armv4
print $_,"\n";
}
close STDOUT; # enforce flush