433 lines
11 KiB
Perl
433 lines
11 KiB
Perl
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#!/usr/bin/env perl
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#
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# ====================================================================
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# Written by Andy Polyakov <appro@openssl.org> for the OpenSSL
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# project. The module is, however, dual licensed under OpenSSL and
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# CRYPTOGAMS licenses depending on where you obtain it. For further
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# details see http://www.openssl.org/~appro/cryptogams/.
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# ====================================================================
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#
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# April 2010
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#
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# The module implements "4-bit" GCM GHASH function and underlying
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# single multiplication operation in GF(2^128). "4-bit" means that it
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# uses 256 bytes per-key table [+32 bytes shared table]. There is no
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# experimental performance data available yet. The only approximation
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# that can be made at this point is based on code size. Inner loop is
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# 32 instructions long and on single-issue core should execute in <40
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# cycles. Having verified that gcc 3.4 didn't unroll corresponding
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# loop, this assembler loop body was found to be ~3x smaller than
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# compiler-generated one...
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#
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# July 2010
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#
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# Rescheduling for dual-issue pipeline resulted in 8.5% improvement on
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# Cortex A8 core and ~25 cycles per processed byte (which was observed
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# to be ~3 times faster than gcc-generated code:-)
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#
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# February 2011
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#
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# Profiler-assisted and platform-specific optimization resulted in 7%
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# improvement on Cortex A8 core and ~23.5 cycles per byte.
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#
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# March 2011
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#
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# Add NEON implementation featuring polynomial multiplication, i.e. no
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# lookup tables involved. On Cortex A8 it was measured to process one
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# byte in 15 cycles or 55% faster than integer-only code.
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# ====================================================================
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# Note about "528B" variant. In ARM case it makes lesser sense to
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# implement it for following reasons:
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#
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# - performance improvement won't be anywhere near 50%, because 128-
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# bit shift operation is neatly fused with 128-bit xor here, and
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# "538B" variant would eliminate only 4-5 instructions out of 32
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# in the inner loop (meaning that estimated improvement is ~15%);
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# - ARM-based systems are often embedded ones and extra memory
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# consumption might be unappreciated (for so little improvement);
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#
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# Byte order [in]dependence. =========================================
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#
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# Caller is expected to maintain specific *dword* order in Htable,
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# namely with *least* significant dword of 128-bit value at *lower*
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# address. This differs completely from C code and has everything to
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# do with ldm instruction and order in which dwords are "consumed" by
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# algorithm. *Byte* order within these dwords in turn is whatever
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# *native* byte order on current platform. See gcm128.c for working
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# example...
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while (($output=shift) && ($output!~/^\w[\w\-]*\.\w+$/)) {}
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open STDOUT,">$output";
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$Xi="r0"; # argument block
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$Htbl="r1";
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$inp="r2";
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$len="r3";
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$Zll="r4"; # variables
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$Zlh="r5";
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$Zhl="r6";
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$Zhh="r7";
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$Tll="r8";
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$Tlh="r9";
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$Thl="r10";
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$Thh="r11";
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$nlo="r12";
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################# r13 is stack pointer
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$nhi="r14";
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################# r15 is program counter
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$rem_4bit=$inp; # used in gcm_gmult_4bit
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$cnt=$len;
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sub Zsmash() {
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my $i=12;
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my @args=@_;
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for ($Zll,$Zlh,$Zhl,$Zhh) {
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$code.=<<___;
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#if __ARM_ARCH__>=7 && defined(__ARMEL__)
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rev $_,$_
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str $_,[$Xi,#$i]
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#elif defined(__ARMEB__)
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str $_,[$Xi,#$i]
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#else
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mov $Tlh,$_,lsr#8
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strb $_,[$Xi,#$i+3]
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mov $Thl,$_,lsr#16
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strb $Tlh,[$Xi,#$i+2]
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mov $Thh,$_,lsr#24
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strb $Thl,[$Xi,#$i+1]
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strb $Thh,[$Xi,#$i]
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#endif
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___
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$code.="\t".shift(@args)."\n";
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$i-=4;
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}
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}
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$code=<<___;
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#if defined(__arm__)
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#include "arm_arch.h"
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.text
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.code 32
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.type rem_4bit,%object
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.align 5
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rem_4bit:
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.short 0x0000,0x1C20,0x3840,0x2460
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.short 0x7080,0x6CA0,0x48C0,0x54E0
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.short 0xE100,0xFD20,0xD940,0xC560
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.short 0x9180,0x8DA0,0xA9C0,0xB5E0
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.size rem_4bit,.-rem_4bit
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.type rem_4bit_get,%function
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rem_4bit_get:
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sub $rem_4bit,pc,#8
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sub $rem_4bit,$rem_4bit,#32 @ &rem_4bit
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b .Lrem_4bit_got
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nop
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.size rem_4bit_get,.-rem_4bit_get
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.global gcm_ghash_4bit
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.type gcm_ghash_4bit,%function
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gcm_ghash_4bit:
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sub r12,pc,#8
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add $len,$inp,$len @ $len to point at the end
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stmdb sp!,{r3-r11,lr} @ save $len/end too
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sub r12,r12,#48 @ &rem_4bit
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ldmia r12,{r4-r11} @ copy rem_4bit ...
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stmdb sp!,{r4-r11} @ ... to stack
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ldrb $nlo,[$inp,#15]
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ldrb $nhi,[$Xi,#15]
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.Louter:
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eor $nlo,$nlo,$nhi
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and $nhi,$nlo,#0xf0
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and $nlo,$nlo,#0x0f
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mov $cnt,#14
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add $Zhh,$Htbl,$nlo,lsl#4
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ldmia $Zhh,{$Zll-$Zhh} @ load Htbl[nlo]
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add $Thh,$Htbl,$nhi
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ldrb $nlo,[$inp,#14]
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and $nhi,$Zll,#0xf @ rem
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ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
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add $nhi,$nhi,$nhi
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eor $Zll,$Tll,$Zll,lsr#4
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ldrh $Tll,[sp,$nhi] @ rem_4bit[rem]
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eor $Zll,$Zll,$Zlh,lsl#28
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ldrb $nhi,[$Xi,#14]
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eor $Zlh,$Tlh,$Zlh,lsr#4
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eor $Zlh,$Zlh,$Zhl,lsl#28
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eor $Zhl,$Thl,$Zhl,lsr#4
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eor $Zhl,$Zhl,$Zhh,lsl#28
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eor $Zhh,$Thh,$Zhh,lsr#4
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eor $nlo,$nlo,$nhi
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and $nhi,$nlo,#0xf0
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and $nlo,$nlo,#0x0f
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eor $Zhh,$Zhh,$Tll,lsl#16
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.Linner:
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add $Thh,$Htbl,$nlo,lsl#4
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and $nlo,$Zll,#0xf @ rem
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subs $cnt,$cnt,#1
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add $nlo,$nlo,$nlo
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ldmia $Thh,{$Tll-$Thh} @ load Htbl[nlo]
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eor $Zll,$Tll,$Zll,lsr#4
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eor $Zll,$Zll,$Zlh,lsl#28
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eor $Zlh,$Tlh,$Zlh,lsr#4
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eor $Zlh,$Zlh,$Zhl,lsl#28
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ldrh $Tll,[sp,$nlo] @ rem_4bit[rem]
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eor $Zhl,$Thl,$Zhl,lsr#4
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ldrplb $nlo,[$inp,$cnt]
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eor $Zhl,$Zhl,$Zhh,lsl#28
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eor $Zhh,$Thh,$Zhh,lsr#4
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add $Thh,$Htbl,$nhi
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and $nhi,$Zll,#0xf @ rem
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eor $Zhh,$Zhh,$Tll,lsl#16 @ ^= rem_4bit[rem]
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add $nhi,$nhi,$nhi
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ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
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eor $Zll,$Tll,$Zll,lsr#4
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ldrplb $Tll,[$Xi,$cnt]
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eor $Zll,$Zll,$Zlh,lsl#28
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eor $Zlh,$Tlh,$Zlh,lsr#4
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ldrh $Tlh,[sp,$nhi]
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eor $Zlh,$Zlh,$Zhl,lsl#28
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eor $Zhl,$Thl,$Zhl,lsr#4
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eor $Zhl,$Zhl,$Zhh,lsl#28
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eorpl $nlo,$nlo,$Tll
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eor $Zhh,$Thh,$Zhh,lsr#4
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andpl $nhi,$nlo,#0xf0
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andpl $nlo,$nlo,#0x0f
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eor $Zhh,$Zhh,$Tlh,lsl#16 @ ^= rem_4bit[rem]
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bpl .Linner
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ldr $len,[sp,#32] @ re-load $len/end
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add $inp,$inp,#16
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mov $nhi,$Zll
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___
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&Zsmash("cmp\t$inp,$len","ldrneb\t$nlo,[$inp,#15]");
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$code.=<<___;
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bne .Louter
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add sp,sp,#36
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#if __ARM_ARCH__>=5
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ldmia sp!,{r4-r11,pc}
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#else
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ldmia sp!,{r4-r11,lr}
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tst lr,#1
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moveq pc,lr @ be binary compatible with V4, yet
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bx lr @ interoperable with Thumb ISA:-)
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#endif
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.size gcm_ghash_4bit,.-gcm_ghash_4bit
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.global gcm_gmult_4bit
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.type gcm_gmult_4bit,%function
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gcm_gmult_4bit:
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stmdb sp!,{r4-r11,lr}
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ldrb $nlo,[$Xi,#15]
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b rem_4bit_get
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.Lrem_4bit_got:
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and $nhi,$nlo,#0xf0
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and $nlo,$nlo,#0x0f
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mov $cnt,#14
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add $Zhh,$Htbl,$nlo,lsl#4
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ldmia $Zhh,{$Zll-$Zhh} @ load Htbl[nlo]
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ldrb $nlo,[$Xi,#14]
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add $Thh,$Htbl,$nhi
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and $nhi,$Zll,#0xf @ rem
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ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
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add $nhi,$nhi,$nhi
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eor $Zll,$Tll,$Zll,lsr#4
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ldrh $Tll,[$rem_4bit,$nhi] @ rem_4bit[rem]
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eor $Zll,$Zll,$Zlh,lsl#28
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eor $Zlh,$Tlh,$Zlh,lsr#4
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eor $Zlh,$Zlh,$Zhl,lsl#28
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eor $Zhl,$Thl,$Zhl,lsr#4
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eor $Zhl,$Zhl,$Zhh,lsl#28
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eor $Zhh,$Thh,$Zhh,lsr#4
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and $nhi,$nlo,#0xf0
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eor $Zhh,$Zhh,$Tll,lsl#16
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and $nlo,$nlo,#0x0f
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.Loop:
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add $Thh,$Htbl,$nlo,lsl#4
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and $nlo,$Zll,#0xf @ rem
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subs $cnt,$cnt,#1
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add $nlo,$nlo,$nlo
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ldmia $Thh,{$Tll-$Thh} @ load Htbl[nlo]
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eor $Zll,$Tll,$Zll,lsr#4
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eor $Zll,$Zll,$Zlh,lsl#28
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eor $Zlh,$Tlh,$Zlh,lsr#4
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eor $Zlh,$Zlh,$Zhl,lsl#28
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ldrh $Tll,[$rem_4bit,$nlo] @ rem_4bit[rem]
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eor $Zhl,$Thl,$Zhl,lsr#4
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ldrplb $nlo,[$Xi,$cnt]
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eor $Zhl,$Zhl,$Zhh,lsl#28
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eor $Zhh,$Thh,$Zhh,lsr#4
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add $Thh,$Htbl,$nhi
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and $nhi,$Zll,#0xf @ rem
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eor $Zhh,$Zhh,$Tll,lsl#16 @ ^= rem_4bit[rem]
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add $nhi,$nhi,$nhi
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ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
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eor $Zll,$Tll,$Zll,lsr#4
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eor $Zll,$Zll,$Zlh,lsl#28
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eor $Zlh,$Tlh,$Zlh,lsr#4
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ldrh $Tll,[$rem_4bit,$nhi] @ rem_4bit[rem]
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eor $Zlh,$Zlh,$Zhl,lsl#28
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eor $Zhl,$Thl,$Zhl,lsr#4
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eor $Zhl,$Zhl,$Zhh,lsl#28
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eor $Zhh,$Thh,$Zhh,lsr#4
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andpl $nhi,$nlo,#0xf0
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andpl $nlo,$nlo,#0x0f
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eor $Zhh,$Zhh,$Tll,lsl#16 @ ^= rem_4bit[rem]
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bpl .Loop
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___
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&Zsmash();
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$code.=<<___;
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#if __ARM_ARCH__>=5
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ldmia sp!,{r4-r11,pc}
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#else
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ldmia sp!,{r4-r11,lr}
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tst lr,#1
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moveq pc,lr @ be binary compatible with V4, yet
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bx lr @ interoperable with Thumb ISA:-)
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#endif
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.size gcm_gmult_4bit,.-gcm_gmult_4bit
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___
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{
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my $cnt=$Htbl; # $Htbl is used once in the very beginning
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my ($Hhi, $Hlo, $Zo, $T, $xi, $mod) = map("d$_",(0..7));
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my ($Qhi, $Qlo, $Z, $R, $zero, $Qpost, $IN) = map("q$_",(8..15));
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# Z:Zo keeps 128-bit result shifted by 1 to the right, with bottom bit
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# in Zo. Or should I say "top bit", because GHASH is specified in
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# reverse bit order? Otherwise straightforward 128-bt H by one input
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# byte multiplication and modulo-reduction, times 16.
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sub Dlo() { shift=~m|q([1]?[0-9])|?"d".($1*2):""; }
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sub Dhi() { shift=~m|q([1]?[0-9])|?"d".($1*2+1):""; }
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sub Q() { shift=~m|d([1-3]?[02468])|?"q".($1/2):""; }
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$code.=<<___;
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#if __ARM_ARCH__>=7
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.fpu neon
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.global gcm_gmult_neon
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.type gcm_gmult_neon,%function
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.align 4
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gcm_gmult_neon:
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sub $Htbl,#16 @ point at H in GCM128_CTX
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vld1.64 `&Dhi("$IN")`,[$Xi,:64]!@ load Xi
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vmov.i32 $mod,#0xe1 @ our irreducible polynomial
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vld1.64 `&Dlo("$IN")`,[$Xi,:64]!
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vshr.u64 $mod,#32
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vldmia $Htbl,{$Hhi-$Hlo} @ load H
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veor $zero,$zero
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#ifdef __ARMEL__
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vrev64.8 $IN,$IN
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#endif
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veor $Qpost,$Qpost
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veor $R,$R
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mov $cnt,#16
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veor $Z,$Z
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mov $len,#16
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veor $Zo,$Zo
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vdup.8 $xi,`&Dlo("$IN")`[0] @ broadcast lowest byte
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b .Linner_neon
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.size gcm_gmult_neon,.-gcm_gmult_neon
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.global gcm_ghash_neon
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.type gcm_ghash_neon,%function
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.align 4
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gcm_ghash_neon:
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vld1.64 `&Dhi("$Z")`,[$Xi,:64]! @ load Xi
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vmov.i32 $mod,#0xe1 @ our irreducible polynomial
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vld1.64 `&Dlo("$Z")`,[$Xi,:64]!
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vshr.u64 $mod,#32
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vldmia $Xi,{$Hhi-$Hlo} @ load H
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veor $zero,$zero
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nop
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|||
|
#ifdef __ARMEL__
|
|||
|
vrev64.8 $Z,$Z
|
|||
|
#endif
|
|||
|
.Louter_neon:
|
|||
|
vld1.64 `&Dhi($IN)`,[$inp]! @ load inp
|
|||
|
veor $Qpost,$Qpost
|
|||
|
vld1.64 `&Dlo($IN)`,[$inp]!
|
|||
|
veor $R,$R
|
|||
|
mov $cnt,#16
|
|||
|
#ifdef __ARMEL__
|
|||
|
vrev64.8 $IN,$IN
|
|||
|
#endif
|
|||
|
veor $Zo,$Zo
|
|||
|
veor $IN,$Z @ inp^=Xi
|
|||
|
veor $Z,$Z
|
|||
|
vdup.8 $xi,`&Dlo("$IN")`[0] @ broadcast lowest byte
|
|||
|
.Linner_neon:
|
|||
|
subs $cnt,$cnt,#1
|
|||
|
vmull.p8 $Qlo,$Hlo,$xi @ H.lo<EFBFBD>Xi[i]
|
|||
|
vmull.p8 $Qhi,$Hhi,$xi @ H.hi<EFBFBD>Xi[i]
|
|||
|
vext.8 $IN,$zero,#1 @ IN>>=8
|
|||
|
|
|||
|
veor $Z,$Qpost @ modulo-scheduled part
|
|||
|
vshl.i64 `&Dlo("$R")`,#48
|
|||
|
vdup.8 $xi,`&Dlo("$IN")`[0] @ broadcast lowest byte
|
|||
|
veor $T,`&Dlo("$Qlo")`,`&Dlo("$Z")`
|
|||
|
|
|||
|
veor `&Dhi("$Z")`,`&Dlo("$R")`
|
|||
|
vuzp.8 $Qlo,$Qhi
|
|||
|
vsli.8 $Zo,$T,#1 @ compose the "carry" byte
|
|||
|
vext.8 $Z,$zero,#1 @ Z>>=8
|
|||
|
|
|||
|
vmull.p8 $R,$Zo,$mod @ "carry"<EFBFBD>0xe1
|
|||
|
vshr.u8 $Zo,$T,#7 @ save Z's bottom bit
|
|||
|
vext.8 $Qpost,$Qlo,$zero,#1 @ Qlo>>=8
|
|||
|
veor $Z,$Qhi
|
|||
|
bne .Linner_neon
|
|||
|
|
|||
|
veor $Z,$Qpost @ modulo-scheduled artefact
|
|||
|
vshl.i64 `&Dlo("$R")`,#48
|
|||
|
veor `&Dhi("$Z")`,`&Dlo("$R")`
|
|||
|
|
|||
|
@ finalization, normalize Z:Zo
|
|||
|
vand $Zo,$mod @ suffices to mask the bit
|
|||
|
vshr.u64 `&Dhi(&Q("$Zo"))`,`&Dlo("$Z")`,#63
|
|||
|
vshl.i64 $Z,#1
|
|||
|
subs $len,#16
|
|||
|
vorr $Z,`&Q("$Zo")` @ Z=Z:Zo<<1
|
|||
|
bne .Louter_neon
|
|||
|
|
|||
|
#ifdef __ARMEL__
|
|||
|
vrev64.8 $Z,$Z
|
|||
|
#endif
|
|||
|
sub $Xi,#16
|
|||
|
vst1.64 `&Dhi("$Z")`,[$Xi,:64]! @ write out Xi
|
|||
|
vst1.64 `&Dlo("$Z")`,[$Xi,:64]
|
|||
|
|
|||
|
bx lr
|
|||
|
.size gcm_ghash_neon,.-gcm_ghash_neon
|
|||
|
#endif
|
|||
|
___
|
|||
|
}
|
|||
|
$code.=<<___;
|
|||
|
.asciz "GHASH for ARMv4/NEON, CRYPTOGAMS by <appro\@openssl.org>"
|
|||
|
.align 2
|
|||
|
|
|||
|
#endif
|
|||
|
___
|
|||
|
|
|||
|
$code =~ s/\`([^\`]*)\`/eval $1/gem;
|
|||
|
$code =~ s/\bbx\s+lr\b/.word\t0xe12fff1e/gm; # make it possible to compile with -march=armv4
|
|||
|
print $code;
|
|||
|
close STDOUT; # enforce flush
|