| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame] | 1 | From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 |
| 2 | From: Uros Bizjak <ubizjak@gmail.com> |
| 3 | Date: Thu, 27 Aug 2020 19:38:31 +0200 |
| 4 | Subject: [PATCH] crypto: poly1305-x86_64 - Use XORL r32,32 |
| 5 | |
| 6 | commit 7dfd1e01b3dfc13431b1b25720cf2692a7e111ef upstream. |
| 7 | |
| 8 | x86_64 zero extends 32bit operations, so for 64bit operands, |
| 9 | XORL r32,r32 is functionally equal to XORQ r64,r64, but avoids |
| 10 | a REX prefix byte when legacy registers are used. |
| 11 | |
| 12 | Signed-off-by: Uros Bizjak <ubizjak@gmail.com> |
| 13 | Cc: Herbert Xu <herbert@gondor.apana.org.au> |
| 14 | Cc: "David S. Miller" <davem@davemloft.net> |
| 15 | Acked-by: Jason A. Donenfeld <Jason@zx2c4.com> |
| 16 | Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> |
| 17 | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> |
| 18 | --- |
| 19 | arch/x86/crypto/poly1305-x86_64-cryptogams.pl | 8 ++++---- |
| 20 | 1 file changed, 4 insertions(+), 4 deletions(-) |
| 21 | |
| 22 | --- a/arch/x86/crypto/poly1305-x86_64-cryptogams.pl |
| 23 | +++ b/arch/x86/crypto/poly1305-x86_64-cryptogams.pl |
| 24 | @@ -246,7 +246,7 @@ $code.=<<___ if (!$kernel); |
| 25 | ___ |
| 26 | &declare_function("poly1305_init_x86_64", 32, 3); |
| 27 | $code.=<<___; |
| 28 | - xor %rax,%rax |
| 29 | + xor %eax,%eax |
| 30 | mov %rax,0($ctx) # initialize hash value |
| 31 | mov %rax,8($ctx) |
| 32 | mov %rax,16($ctx) |
| 33 | @@ -2869,7 +2869,7 @@ $code.=<<___; |
| 34 | .type poly1305_init_base2_44,\@function,3 |
| 35 | .align 32 |
| 36 | poly1305_init_base2_44: |
| 37 | - xor %rax,%rax |
| 38 | + xor %eax,%eax |
| 39 | mov %rax,0($ctx) # initialize hash value |
| 40 | mov %rax,8($ctx) |
| 41 | mov %rax,16($ctx) |
| 42 | @@ -3963,7 +3963,7 @@ xor128_decrypt_n_pad: |
| 43 | mov \$16,$len |
| 44 | sub %r10,$len |
| 45 | xor %eax,%eax |
| 46 | - xor %r11,%r11 |
| 47 | + xor %r11d,%r11d |
| 48 | .Loop_dec_byte: |
| 49 | mov ($inp,$otp),%r11b |
| 50 | mov ($otp),%al |
| 51 | @@ -4101,7 +4101,7 @@ avx_handler: |
| 52 | .long 0xa548f3fc # cld; rep movsq |
| 53 | |
| 54 | mov $disp,%rsi |
| 55 | - xor %rcx,%rcx # arg1, UNW_FLAG_NHANDLER |
| 56 | + xor %ecx,%ecx # arg1, UNW_FLAG_NHANDLER |
| 57 | mov 8(%rsi),%rdx # arg2, disp->ImageBase |
| 58 | mov 0(%rsi),%r8 # arg3, disp->ControlPc |
| 59 | mov 16(%rsi),%r9 # arg4, disp->FunctionEntry |