Commit 7dfd1e01 authored by Uros Bizjak's avatar Uros Bizjak Committed by Herbert Xu
Browse files

crypto: poly1305-x86_64 - Use XORL r32,32 



x86_64 zero extends 32bit operations, so for 64bit operands,
XORL r32,r32 is functionally equal to XORQ r64,r64, but avoids
a REX prefix byte when legacy registers are used.

Signed-off-by: default avatarUros Bizjak <ubizjak@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: default avatarJason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent db719539

arch/x86/crypto/poly1305-x86_64-cryptogams.pl

+4 −4
Original line number Diff line number Diff line
@@ -246,7 +246,7 @@ $code.=<<___ if (!$kernel); 
___

&declare_function("poly1305_init_x86_64", 32, 3);

$code.=<<___;

	xor	%rax,%rax

	xor	%eax,%eax

	mov	%rax,0($ctx)		# initialize hash value

	mov	%rax,8($ctx)

	mov	%rax,16($ctx)
@@ -2853,7 +2853,7 @@ $code.=<<___; 
.type	poly1305_init_base2_44,\@function,3

.align	32

poly1305_init_base2_44:

	xor	%rax,%rax

	xor	%eax,%eax

	mov	%rax,0($ctx)		# initialize hash value

	mov	%rax,8($ctx)

	mov	%rax,16($ctx)
@@ -3947,7 +3947,7 @@ xor128_decrypt_n_pad: 
	mov	\$16,$len

	sub	%r10,$len

	xor	%eax,%eax

	xor	%r11,%r11

	xor	%r11d,%r11d

.Loop_dec_byte:

	mov	($inp,$otp),%r11b

	mov	($otp),%al
@@ -4085,7 +4085,7 @@ avx_handler: 
	.long	0xa548f3fc		# cld; rep movsq



	mov	$disp,%rsi

	xor	%rcx,%rcx		# arg1, UNW_FLAG_NHANDLER

	xor	%ecx,%ecx		# arg1, UNW_FLAG_NHANDLER

	mov	8(%rsi),%rdx		# arg2, disp->ImageBase

	mov	0(%rsi),%r8		# arg3, disp->ControlPc

	mov	16(%rsi),%r9		# arg4, disp->FunctionEntry