From: Uros Bizjak <ubizjak@gmail.com>
Date: Thu, 27 Aug 2020 17:38:31 +0000 (+0200)
Subject: crypto: poly1305-x86_64 - Use XORL r32,32
X-Git-Tag: v5.10-rc1~181^2~142
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=7dfd1e01b3dfc13431b1b25720cf2692a7e111ef;p=thirdparty%2Fkernel%2Flinux.git

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

diff --git a/arch/x86/crypto/poly1305-x86_64-cryptogams.pl b/arch/x86/crypto/poly1305-x86_64-cryptogams.pl
index 137edcf038cb7..7d568012cc15b 100644
--- a/arch/x86/crypto/poly1305-x86_64-cryptogams.pl
+++ b/arch/x86/crypto/poly1305-x86_64-cryptogams.pl
@@ -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