[PATCH 5.10 01/13] crypto: aesni - Use TEST %reg,%reg instead of CMP $0,%reg

From: Greg Kroah-Hartman
Date: Fri Mar 19 2021 - 08:21:04 EST


From: Uros Bizjak <ubizjak@xxxxxxxxx>

[ Upstream commit 032d049ea0f45b45c21f3f02b542aa18bc6b6428 ]

CMP $0,%reg can't set overflow flag, so we can use shorter TEST %reg,%reg
instruction when only zero and sign flags are checked (E,L,LE,G,GE conditions).

Signed-off-by: Uros Bizjak <ubizjak@xxxxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/x86/crypto/aesni-intel_asm.S | 20 ++++++++++----------
arch/x86/crypto/aesni-intel_avx-x86_64.S | 20 ++++++++++----------
2 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/arch/x86/crypto/aesni-intel_asm.S b/arch/x86/crypto/aesni-intel_asm.S
index 1852b19a73a0..d1436c37008b 100644
--- a/arch/x86/crypto/aesni-intel_asm.S
+++ b/arch/x86/crypto/aesni-intel_asm.S
@@ -318,7 +318,7 @@ _initial_blocks_\@:

# Main loop - Encrypt/Decrypt remaining blocks

- cmp $0, %r13
+ test %r13, %r13
je _zero_cipher_left_\@
sub $64, %r13
je _four_cipher_left_\@
@@ -437,7 +437,7 @@ _multiple_of_16_bytes_\@:

mov PBlockLen(%arg2), %r12

- cmp $0, %r12
+ test %r12, %r12
je _partial_done\@

GHASH_MUL %xmm8, %xmm13, %xmm9, %xmm10, %xmm11, %xmm5, %xmm6
@@ -474,7 +474,7 @@ _T_8_\@:
add $8, %r10
sub $8, %r11
psrldq $8, %xmm0
- cmp $0, %r11
+ test %r11, %r11
je _return_T_done_\@
_T_4_\@:
movd %xmm0, %eax
@@ -482,7 +482,7 @@ _T_4_\@:
add $4, %r10
sub $4, %r11
psrldq $4, %xmm0
- cmp $0, %r11
+ test %r11, %r11
je _return_T_done_\@
_T_123_\@:
movd %xmm0, %eax
@@ -619,7 +619,7 @@ _get_AAD_blocks\@:

/* read the last <16B of AAD */
_get_AAD_rest\@:
- cmp $0, %r11
+ test %r11, %r11
je _get_AAD_done\@

READ_PARTIAL_BLOCK %r10, %r11, \TMP1, \TMP7
@@ -640,7 +640,7 @@ _get_AAD_done\@:
.macro PARTIAL_BLOCK CYPH_PLAIN_OUT PLAIN_CYPH_IN PLAIN_CYPH_LEN DATA_OFFSET \
AAD_HASH operation
mov PBlockLen(%arg2), %r13
- cmp $0, %r13
+ test %r13, %r13
je _partial_block_done_\@ # Leave Macro if no partial blocks
# Read in input data without over reading
cmp $16, \PLAIN_CYPH_LEN
@@ -692,7 +692,7 @@ _no_extra_mask_1_\@:
pshufb %xmm2, %xmm3
pxor %xmm3, \AAD_HASH

- cmp $0, %r10
+ test %r10, %r10
jl _partial_incomplete_1_\@

# GHASH computation for the last <16 Byte block
@@ -727,7 +727,7 @@ _no_extra_mask_2_\@:
pshufb %xmm2, %xmm9
pxor %xmm9, \AAD_HASH

- cmp $0, %r10
+ test %r10, %r10
jl _partial_incomplete_2_\@

# GHASH computation for the last <16 Byte block
@@ -747,7 +747,7 @@ _encode_done_\@:
pshufb %xmm2, %xmm9
.endif
# output encrypted Bytes
- cmp $0, %r10
+ test %r10, %r10
jl _partial_fill_\@
mov %r13, %r12
mov $16, %r13
@@ -2720,7 +2720,7 @@ SYM_FUNC_END(aesni_ctr_enc)
*/
SYM_FUNC_START(aesni_xts_crypt8)
FRAME_BEGIN
- cmpb $0, %cl
+ testb %cl, %cl
movl $0, %ecx
movl $240, %r10d
leaq _aesni_enc4, %r11
diff --git a/arch/x86/crypto/aesni-intel_avx-x86_64.S b/arch/x86/crypto/aesni-intel_avx-x86_64.S
index 5fee47956f3b..2cf8e94d986a 100644
--- a/arch/x86/crypto/aesni-intel_avx-x86_64.S
+++ b/arch/x86/crypto/aesni-intel_avx-x86_64.S
@@ -369,7 +369,7 @@ _initial_num_blocks_is_0\@:


_initial_blocks_encrypted\@:
- cmp $0, %r13
+ test %r13, %r13
je _zero_cipher_left\@

sub $128, %r13
@@ -528,7 +528,7 @@ _multiple_of_16_bytes\@:
vmovdqu HashKey(arg2), %xmm13

mov PBlockLen(arg2), %r12
- cmp $0, %r12
+ test %r12, %r12
je _partial_done\@

#GHASH computation for the last <16 Byte block
@@ -573,7 +573,7 @@ _T_8\@:
add $8, %r10
sub $8, %r11
vpsrldq $8, %xmm9, %xmm9
- cmp $0, %r11
+ test %r11, %r11
je _return_T_done\@
_T_4\@:
vmovd %xmm9, %eax
@@ -581,7 +581,7 @@ _T_4\@:
add $4, %r10
sub $4, %r11
vpsrldq $4, %xmm9, %xmm9
- cmp $0, %r11
+ test %r11, %r11
je _return_T_done\@
_T_123\@:
vmovd %xmm9, %eax
@@ -625,7 +625,7 @@ _get_AAD_blocks\@:
cmp $16, %r11
jge _get_AAD_blocks\@
vmovdqu \T8, \T7
- cmp $0, %r11
+ test %r11, %r11
je _get_AAD_done\@

vpxor \T7, \T7, \T7
@@ -644,7 +644,7 @@ _get_AAD_rest8\@:
vpxor \T1, \T7, \T7
jmp _get_AAD_rest8\@
_get_AAD_rest4\@:
- cmp $0, %r11
+ test %r11, %r11
jle _get_AAD_rest0\@
mov (%r10), %eax
movq %rax, \T1
@@ -749,7 +749,7 @@ _done_read_partial_block_\@:
.macro PARTIAL_BLOCK GHASH_MUL CYPH_PLAIN_OUT PLAIN_CYPH_IN PLAIN_CYPH_LEN DATA_OFFSET \
AAD_HASH ENC_DEC
mov PBlockLen(arg2), %r13
- cmp $0, %r13
+ test %r13, %r13
je _partial_block_done_\@ # Leave Macro if no partial blocks
# Read in input data without over reading
cmp $16, \PLAIN_CYPH_LEN
@@ -801,7 +801,7 @@ _no_extra_mask_1_\@:
vpshufb %xmm2, %xmm3, %xmm3
vpxor %xmm3, \AAD_HASH, \AAD_HASH

- cmp $0, %r10
+ test %r10, %r10
jl _partial_incomplete_1_\@

# GHASH computation for the last <16 Byte block
@@ -836,7 +836,7 @@ _no_extra_mask_2_\@:
vpshufb %xmm2, %xmm9, %xmm9
vpxor %xmm9, \AAD_HASH, \AAD_HASH

- cmp $0, %r10
+ test %r10, %r10
jl _partial_incomplete_2_\@

# GHASH computation for the last <16 Byte block
@@ -856,7 +856,7 @@ _encode_done_\@:
vpshufb %xmm2, %xmm9, %xmm9
.endif
# output encrypted Bytes
- cmp $0, %r10
+ test %r10, %r10
jl _partial_fill_\@
mov %r13, %r12
mov $16, %r13
--
2.30.1