[PATCH 6/7] crypto: aesni: make AVX2 AES-GCM work with all valid auth_tag_len

From: Sabrina Dubroca
Date: Fri Apr 28 2017 - 12:15:14 EST


Signed-off-by: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx>
---
arch/x86/crypto/aesni-intel_avx-x86_64.S | 31 ++++++++++++++++++++++++-------
1 file changed, 24 insertions(+), 7 deletions(-)

diff --git a/arch/x86/crypto/aesni-intel_avx-x86_64.S b/arch/x86/crypto/aesni-intel_avx-x86_64.S
index 7230808a7cef..faecb1518bf8 100644
--- a/arch/x86/crypto/aesni-intel_avx-x86_64.S
+++ b/arch/x86/crypto/aesni-intel_avx-x86_64.S
@@ -2804,19 +2804,36 @@ ENDPROC(aesni_gcm_dec_avx_gen2)
cmp $16, %r11
je _T_16\@

- cmp $12, %r11
- je _T_12\@
+ cmp $8, %r11
+ jl _T_4\@

_T_8\@:
vmovq %xmm9, %rax
mov %rax, (%r10)
- jmp _return_T_done\@
-_T_12\@:
- vmovq %xmm9, %rax
- mov %rax, (%r10)
+ add $8, %r10
+ sub $8, %r11
vpsrldq $8, %xmm9, %xmm9
+ cmp $0, %r11
+ je _return_T_done\@
+_T_4\@:
vmovd %xmm9, %eax
- mov %eax, 8(%r10)
+ mov %eax, (%r10)
+ add $4, %r10
+ sub $4, %r11
+ vpsrldq $4, %xmm9, %xmm9
+ cmp $0, %r11
+ je _return_T_done\@
+_T_123\@:
+ vmovd %xmm9, %eax
+ cmp $2, %r11
+ jl _T_1\@
+ mov %ax, (%r10)
+ cmp $2, %r11
+ je _return_T_done\@
+ add $2, %r10
+ sar $16, %eax
+_T_1\@:
+ mov %al, (%r10)
jmp _return_T_done\@

_T_16\@:
--
2.12.2