410 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			Perl
		
	
	
	
	
	
			
		
		
	
	
			410 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			Perl
		
	
	
	
	
	
| #!/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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| # GHASH for ARMv8 Crypto Extension, 64-bit polynomial multiplication.
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| #
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| # June 2014
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| #
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| # Initial version was developed in tight cooperation with Ard
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| # Biesheuvel <ard.biesheuvel@linaro.org> from bits-n-pieces from
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| # other assembly modules. Just like aesv8-armx.pl this module
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| # supports both AArch32 and AArch64 execution modes.
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| #
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| # July 2014
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| #
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| # Implement 2x aggregated reduction [see ghash-x86.pl for background
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| # information].
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| #
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| # Current performance in cycles per processed byte:
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| #
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| #		PMULL[2]	32-bit NEON(*)
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| # Apple A7	0.92		5.62
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| # Cortex-A53	1.01		8.39
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| # Cortex-A57	1.17		7.61
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| #
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| # (*)	presented for reference/comparison purposes;
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| 
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| $flavour = shift;
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| open STDOUT,">".shift;
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| 
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| $Xi="x0";	# argument block
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| $Htbl="x1";
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| $inp="x2";
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| $len="x3";
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| 
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| $inc="x12";
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| 
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| {
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| my ($Xl,$Xm,$Xh,$IN)=map("q$_",(0..3));
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| my ($t0,$t1,$t2,$xC2,$H,$Hhl,$H2)=map("q$_",(8..14));
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| 
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| $code=<<___;
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| #include "arm_arch.h"
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| 
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| .text
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| ___
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| $code.=".arch	armv8-a+crypto\n"	if ($flavour =~ /64/);
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| $code.=".fpu	neon\n.code	32\n"	if ($flavour !~ /64/);
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| 
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| ################################################################################
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| # void gcm_init_v8(u128 Htable[16],const u64 H[2]);
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| #
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| # input:	128-bit H - secret parameter E(K,0^128)
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| # output:	precomputed table filled with degrees of twisted H;
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| #		H is twisted to handle reverse bitness of GHASH;
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| #		only few of 16 slots of Htable[16] are used;
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| #		data is opaque to outside world (which allows to
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| #		optimize the code independently);
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| #
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| $code.=<<___;
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| .global	gcm_init_v8
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| .type	gcm_init_v8,%function
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| .align	4
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| gcm_init_v8:
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| 	vld1.64		{$t1},[x1]		@ load input H
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| 	vmov.i8		$xC2,#0xe1
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| 	vshl.i64	$xC2,$xC2,#57		@ 0xc2.0
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| 	vext.8		$IN,$t1,$t1,#8
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| 	vshr.u64	$t2,$xC2,#63
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| 	vdup.32		$t1,${t1}[1]
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| 	vext.8		$t0,$t2,$xC2,#8		@ t0=0xc2....01
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| 	vshr.u64	$t2,$IN,#63
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| 	vshr.s32	$t1,$t1,#31		@ broadcast carry bit
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| 	vand		$t2,$t2,$t0
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| 	vshl.i64	$IN,$IN,#1
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| 	vext.8		$t2,$t2,$t2,#8
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| 	vand		$t0,$t0,$t1
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| 	vorr		$IN,$IN,$t2		@ H<<<=1
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| 	veor		$H,$IN,$t0		@ twisted H
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| 	vst1.64		{$H},[x0],#16		@ store Htable[0]
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| 
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| 	@ calculate H^2
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| 	vext.8		$t0,$H,$H,#8		@ Karatsuba pre-processing
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| 	vpmull.p64	$Xl,$H,$H
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| 	veor		$t0,$t0,$H
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| 	vpmull2.p64	$Xh,$H,$H
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| 	vpmull.p64	$Xm,$t0,$t0
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| 
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| 	vext.8		$t1,$Xl,$Xh,#8		@ Karatsuba post-processing
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| 	veor		$t2,$Xl,$Xh
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| 	veor		$Xm,$Xm,$t1
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| 	veor		$Xm,$Xm,$t2
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| 	vpmull.p64	$t2,$Xl,$xC2		@ 1st phase
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| 
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| 	vmov		$Xh#lo,$Xm#hi		@ Xh|Xm - 256-bit result
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| 	vmov		$Xm#hi,$Xl#lo		@ Xm is rotated Xl
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| 	veor		$Xl,$Xm,$t2
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| 
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| 	vext.8		$t2,$Xl,$Xl,#8		@ 2nd phase
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| 	vpmull.p64	$Xl,$Xl,$xC2
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| 	veor		$t2,$t2,$Xh
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| 	veor		$H2,$Xl,$t2
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| 
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| 	vext.8		$t1,$H2,$H2,#8		@ Karatsuba pre-processing
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| 	veor		$t1,$t1,$H2
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| 	vext.8		$Hhl,$t0,$t1,#8		@ pack Karatsuba pre-processed
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| 	vst1.64		{$Hhl-$H2},[x0]		@ store Htable[1..2]
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| 
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| 	ret
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| .size	gcm_init_v8,.-gcm_init_v8
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| ___
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| ################################################################################
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| # void gcm_gmult_v8(u64 Xi[2],const u128 Htable[16]);
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| #
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| # input:	Xi - current hash value;
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| #		Htable - table precomputed in gcm_init_v8;
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| # output:	Xi - next hash value Xi;
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| #
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| $code.=<<___;
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| .global	gcm_gmult_v8
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| .type	gcm_gmult_v8,%function
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| .align	4
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| gcm_gmult_v8:
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| 	vld1.64		{$t1},[$Xi]		@ load Xi
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| 	vmov.i8		$xC2,#0xe1
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| 	vld1.64		{$H-$Hhl},[$Htbl]	@ load twisted H, ...
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| 	vshl.u64	$xC2,$xC2,#57
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| #ifndef __ARMEB__
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| 	vrev64.8	$t1,$t1
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| #endif
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| 	vext.8		$IN,$t1,$t1,#8
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| 
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| 	vpmull.p64	$Xl,$H,$IN		@ H.lo<6C>Xi.lo
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| 	veor		$t1,$t1,$IN		@ Karatsuba pre-processing
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| 	vpmull2.p64	$Xh,$H,$IN		@ H.hi<68>Xi.hi
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| 	vpmull.p64	$Xm,$Hhl,$t1		@ (H.lo+H.hi)<29>(Xi.lo+Xi.hi)
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| 
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| 	vext.8		$t1,$Xl,$Xh,#8		@ Karatsuba post-processing
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| 	veor		$t2,$Xl,$Xh
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| 	veor		$Xm,$Xm,$t1
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| 	veor		$Xm,$Xm,$t2
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| 	vpmull.p64	$t2,$Xl,$xC2		@ 1st phase of reduction
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| 
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| 	vmov		$Xh#lo,$Xm#hi		@ Xh|Xm - 256-bit result
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| 	vmov		$Xm#hi,$Xl#lo		@ Xm is rotated Xl
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| 	veor		$Xl,$Xm,$t2
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| 
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| 	vext.8		$t2,$Xl,$Xl,#8		@ 2nd phase of reduction
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| 	vpmull.p64	$Xl,$Xl,$xC2
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| 	veor		$t2,$t2,$Xh
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| 	veor		$Xl,$Xl,$t2
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| 
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| #ifndef __ARMEB__
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| 	vrev64.8	$Xl,$Xl
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| #endif
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| 	vext.8		$Xl,$Xl,$Xl,#8
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| 	vst1.64		{$Xl},[$Xi]		@ write out Xi
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| 
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| 	ret
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| .size	gcm_gmult_v8,.-gcm_gmult_v8
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| ___
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| ################################################################################
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| # void gcm_ghash_v8(u64 Xi[2],const u128 Htable[16],const u8 *inp,size_t len);
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| #
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| # input:	table precomputed in gcm_init_v8;
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| #		current hash value Xi;
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| #		pointer to input data;
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| #		length of input data in bytes, but divisible by block size;
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| # output:	next hash value Xi;
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| #
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| $code.=<<___;
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| .global	gcm_ghash_v8
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| .type	gcm_ghash_v8,%function
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| .align	4
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| gcm_ghash_v8:
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| ___
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| $code.=<<___		if ($flavour !~ /64/);
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| 	vstmdb		sp!,{d8-d15}		@ 32-bit ABI says so
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| ___
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| $code.=<<___;
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| 	vld1.64		{$Xl},[$Xi]		@ load [rotated] Xi
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| 						@ "[rotated]" means that
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| 						@ loaded value would have
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| 						@ to be rotated in order to
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| 						@ make it appear as in
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| 						@ alorithm specification
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| 	subs		$len,$len,#32		@ see if $len is 32 or larger
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| 	mov		$inc,#16		@ $inc is used as post-
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| 						@ increment for input pointer;
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| 						@ as loop is modulo-scheduled
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| 						@ $inc is zeroed just in time
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| 						@ to preclude oversteping
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| 						@ inp[len], which means that
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| 						@ last block[s] are actually
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| 						@ loaded twice, but last
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| 						@ copy is not processed
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| 	vld1.64		{$H-$Hhl},[$Htbl],#32	@ load twisted H, ..., H^2
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| 	vmov.i8		$xC2,#0xe1
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| 	vld1.64		{$H2},[$Htbl]
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| 	cclr		$inc,eq			@ is it time to zero $inc?
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| 	vext.8		$Xl,$Xl,$Xl,#8		@ rotate Xi
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| 	vld1.64		{$t0},[$inp],#16	@ load [rotated] I[0]
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| 	vshl.u64	$xC2,$xC2,#57		@ compose 0xc2.0 constant
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| #ifndef __ARMEB__
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| 	vrev64.8	$t0,$t0
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| 	vrev64.8	$Xl,$Xl
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| #endif
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| 	vext.8		$IN,$t0,$t0,#8		@ rotate I[0]
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| 	b.lo		.Lodd_tail_v8		@ $len was less than 32
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| ___
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| { my ($Xln,$Xmn,$Xhn,$In) = map("q$_",(4..7));
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| 	#######
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| 	# Xi+2 =[H*(Ii+1 + Xi+1)] mod P =
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| 	#	[(H*Ii+1) + (H*Xi+1)] mod P =
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| 	#	[(H*Ii+1) + H^2*(Ii+Xi)] mod P
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| 	#
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| $code.=<<___;
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| 	vld1.64		{$t1},[$inp],$inc	@ load [rotated] I[1]
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| #ifndef __ARMEB__
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| 	vrev64.8	$t1,$t1
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| #endif
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| 	vext.8		$In,$t1,$t1,#8
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| 	veor		$IN,$IN,$Xl		@ I[i]^=Xi
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| 	vpmull.p64	$Xln,$H,$In		@ H<>Ii+1
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| 	veor		$t1,$t1,$In		@ Karatsuba pre-processing
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| 	vpmull2.p64	$Xhn,$H,$In
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| 	b		.Loop_mod2x_v8
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| 
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| .align	4
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| .Loop_mod2x_v8:
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| 	vext.8		$t2,$IN,$IN,#8
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| 	subs		$len,$len,#32		@ is there more data?
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| 	vpmull.p64	$Xl,$H2,$IN		@ H^2.lo<6C>Xi.lo
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| 	cclr		$inc,lo			@ is it time to zero $inc?
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| 
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| 	 vpmull.p64	$Xmn,$Hhl,$t1
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| 	veor		$t2,$t2,$IN		@ Karatsuba pre-processing
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| 	vpmull2.p64	$Xh,$H2,$IN		@ H^2.hi<68>Xi.hi
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| 	veor		$Xl,$Xl,$Xln		@ accumulate
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| 	vpmull2.p64	$Xm,$Hhl,$t2		@ (H^2.lo+H^2.hi)<29>(Xi.lo+Xi.hi)
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| 	 vld1.64	{$t0},[$inp],$inc	@ load [rotated] I[i+2]
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| 
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| 	veor		$Xh,$Xh,$Xhn
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| 	 cclr		$inc,eq			@ is it time to zero $inc?
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| 	veor		$Xm,$Xm,$Xmn
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| 
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| 	vext.8		$t1,$Xl,$Xh,#8		@ Karatsuba post-processing
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| 	veor		$t2,$Xl,$Xh
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| 	veor		$Xm,$Xm,$t1
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| 	 vld1.64	{$t1},[$inp],$inc	@ load [rotated] I[i+3]
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| #ifndef __ARMEB__
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| 	 vrev64.8	$t0,$t0
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| #endif
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| 	veor		$Xm,$Xm,$t2
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| 	vpmull.p64	$t2,$Xl,$xC2		@ 1st phase of reduction
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| 
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| #ifndef __ARMEB__
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| 	 vrev64.8	$t1,$t1
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| #endif
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| 	vmov		$Xh#lo,$Xm#hi		@ Xh|Xm - 256-bit result
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| 	vmov		$Xm#hi,$Xl#lo		@ Xm is rotated Xl
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| 	 vext.8		$In,$t1,$t1,#8
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| 	 vext.8		$IN,$t0,$t0,#8
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| 	veor		$Xl,$Xm,$t2
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| 	 vpmull.p64	$Xln,$H,$In		@ H<>Ii+1
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| 	veor		$IN,$IN,$Xh		@ accumulate $IN early
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| 
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| 	vext.8		$t2,$Xl,$Xl,#8		@ 2nd phase of reduction
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| 	vpmull.p64	$Xl,$Xl,$xC2
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| 	veor		$IN,$IN,$t2
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| 	 veor		$t1,$t1,$In		@ Karatsuba pre-processing
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| 	veor		$IN,$IN,$Xl
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| 	 vpmull2.p64	$Xhn,$H,$In
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| 	b.hs		.Loop_mod2x_v8		@ there was at least 32 more bytes
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| 
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| 	veor		$Xh,$Xh,$t2
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| 	vext.8		$IN,$t0,$t0,#8		@ re-construct $IN
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| 	adds		$len,$len,#32		@ re-construct $len
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| 	veor		$Xl,$Xl,$Xh		@ re-construct $Xl
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| 	b.eq		.Ldone_v8		@ is $len zero?
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| ___
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| }
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| $code.=<<___;
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| .Lodd_tail_v8:
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| 	vext.8		$t2,$Xl,$Xl,#8
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| 	veor		$IN,$IN,$Xl		@ inp^=Xi
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| 	veor		$t1,$t0,$t2		@ $t1 is rotated inp^Xi
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| 
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| 	vpmull.p64	$Xl,$H,$IN		@ H.lo<6C>Xi.lo
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| 	veor		$t1,$t1,$IN		@ Karatsuba pre-processing
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| 	vpmull2.p64	$Xh,$H,$IN		@ H.hi<68>Xi.hi
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| 	vpmull.p64	$Xm,$Hhl,$t1		@ (H.lo+H.hi)<29>(Xi.lo+Xi.hi)
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| 
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| 	vext.8		$t1,$Xl,$Xh,#8		@ Karatsuba post-processing
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| 	veor		$t2,$Xl,$Xh
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| 	veor		$Xm,$Xm,$t1
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| 	veor		$Xm,$Xm,$t2
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| 	vpmull.p64	$t2,$Xl,$xC2		@ 1st phase of reduction
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| 
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| 	vmov		$Xh#lo,$Xm#hi		@ Xh|Xm - 256-bit result
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| 	vmov		$Xm#hi,$Xl#lo		@ Xm is rotated Xl
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| 	veor		$Xl,$Xm,$t2
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| 
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| 	vext.8		$t2,$Xl,$Xl,#8		@ 2nd phase of reduction
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| 	vpmull.p64	$Xl,$Xl,$xC2
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| 	veor		$t2,$t2,$Xh
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| 	veor		$Xl,$Xl,$t2
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| 
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| .Ldone_v8:
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| #ifndef __ARMEB__
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| 	vrev64.8	$Xl,$Xl
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| #endif
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| 	vext.8		$Xl,$Xl,$Xl,#8
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| 	vst1.64		{$Xl},[$Xi]		@ write out Xi
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| 
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| ___
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| $code.=<<___		if ($flavour !~ /64/);
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| 	vldmia		sp!,{d8-d15}		@ 32-bit ABI says so
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| ___
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| $code.=<<___;
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| 	ret
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| .size	gcm_ghash_v8,.-gcm_ghash_v8
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| ___
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| }
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| $code.=<<___;
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| .asciz  "GHASH for ARMv8, CRYPTOGAMS by <appro\@openssl.org>"
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| .align  2
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| ___
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| 
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| if ($flavour =~ /64/) {			######## 64-bit code
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|     sub unvmov {
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| 	my $arg=shift;
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| 
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| 	$arg =~ m/q([0-9]+)#(lo|hi),\s*q([0-9]+)#(lo|hi)/o &&
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| 	sprintf	"ins	v%d.d[%d],v%d.d[%d]",$1,($2 eq "lo")?0:1,$3,($4 eq "lo")?0:1;
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|     }
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|     foreach(split("\n",$code)) {
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| 	s/cclr\s+([wx])([^,]+),\s*([a-z]+)/csel	$1$2,$1zr,$1$2,$3/o	or
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| 	s/vmov\.i8/movi/o		or	# fix up legacy mnemonics
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| 	s/vmov\s+(.*)/unvmov($1)/geo	or
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| 	s/vext\.8/ext/o			or
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| 	s/vshr\.s/sshr\.s/o		or
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| 	s/vshr/ushr/o			or
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| 	s/^(\s+)v/$1/o			or	# strip off v prefix
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| 	s/\bbx\s+lr\b/ret/o;
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| 
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| 	s/\bq([0-9]+)\b/"v".($1<8?$1:$1+8).".16b"/geo;	# old->new registers
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| 	s/@\s/\/\//o;				# old->new style commentary
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| 
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| 	# fix up remainig legacy suffixes
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| 	s/\.[ui]?8(\s)/$1/o;
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| 	s/\.[uis]?32//o and s/\.16b/\.4s/go;
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| 	m/\.p64/o and s/\.16b/\.1q/o;		# 1st pmull argument
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| 	m/l\.p64/o and s/\.16b/\.1d/go;		# 2nd and 3rd pmull arguments
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| 	s/\.[uisp]?64//o and s/\.16b/\.2d/go;
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| 	s/\.[42]([sd])\[([0-3])\]/\.$1\[$2\]/o;
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| 
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| 	print $_,"\n";
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|     }
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| } else {				######## 32-bit code
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|     sub unvdup32 {
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| 	my $arg=shift;
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| 
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| 	$arg =~ m/q([0-9]+),\s*q([0-9]+)\[([0-3])\]/o &&
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| 	sprintf	"vdup.32	q%d,d%d[%d]",$1,2*$2+($3>>1),$3&1;
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|     }
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|     sub unvpmullp64 {
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| 	my ($mnemonic,$arg)=@_;
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| 
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| 	if ($arg =~ m/q([0-9]+),\s*q([0-9]+),\s*q([0-9]+)/o) {
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| 	    my $word = 0xf2a00e00|(($1&7)<<13)|(($1&8)<<19)
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| 				 |(($2&7)<<17)|(($2&8)<<4)
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| 				 |(($3&7)<<1) |(($3&8)<<2);
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| 	    $word |= 0x00010001	 if ($mnemonic =~ "2");
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| 	    # since ARMv7 instructions are always encoded little-endian.
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| 	    # correct solution is to use .inst directive, but older
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| 	    # assemblers don't implement it:-(
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| 	    sprintf ".byte\t0x%02x,0x%02x,0x%02x,0x%02x\t@ %s %s",
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| 			$word&0xff,($word>>8)&0xff,
 | ||
| 			($word>>16)&0xff,($word>>24)&0xff,
 | ||
| 			$mnemonic,$arg;
 | ||
| 	}
 | ||
|     }
 | ||
| 
 | ||
|     foreach(split("\n",$code)) {
 | ||
| 	s/\b[wx]([0-9]+)\b/r$1/go;		# new->old registers
 | ||
| 	s/\bv([0-9])\.[12468]+[bsd]\b/q$1/go;	# new->old registers
 | ||
| 	s/\/\/\s?/@ /o;				# new->old style commentary
 | ||
| 
 | ||
| 	# fix up remainig new-style suffixes
 | ||
| 	s/\],#[0-9]+/]!/o;
 | ||
| 
 | ||
| 	s/cclr\s+([^,]+),\s*([a-z]+)/mov$2	$1,#0/o			or
 | ||
| 	s/vdup\.32\s+(.*)/unvdup32($1)/geo				or
 | ||
| 	s/v?(pmull2?)\.p64\s+(.*)/unvpmullp64($1,$2)/geo		or
 | ||
| 	s/\bq([0-9]+)#(lo|hi)/sprintf "d%d",2*$1+($2 eq "hi")/geo	or
 | ||
| 	s/^(\s+)b\./$1b/o						or
 | ||
| 	s/^(\s+)ret/$1bx\tlr/o;
 | ||
| 
 | ||
| 	print $_,"\n";
 | ||
|     }
 | ||
| }
 | ||
| 
 | ||
| close STDOUT; # enforce flush
 | 
