diff options
| author | Niels Möller <nisse@lysator.liu.se> | 2023-04-08 21:27:21 +0200 |
|---|---|---|
| committer | Niels Möller <nisse@lysator.liu.se> | 2023-04-08 21:27:21 +0200 |
| commit | 13fc36ff54fb0fd6095965d0cb870c0710f1746b (patch) | |
| tree | ea32ae6512e391aed06ddc0ccfb83ea1ed290530 | |
| parent | e7267628cbc9299f21fb335cb99586f4e925de7e (diff) | |
| download | nettle-13fc36ff54fb0fd6095965d0cb870c0710f1746b.tar.gz | |
Use sign bits and arithmetic right shift.
| -rw-r--r-- | x86_64/ghash-update.asm | 27 |
1 files changed, 10 insertions, 17 deletions
diff --git a/x86_64/ghash-update.asm b/x86_64/ghash-update.asm index 4e008e5a..649f8680 100644 --- a/x86_64/ghash-update.asm +++ b/x86_64/ghash-update.asm @@ -41,7 +41,6 @@ define(`X', `%xmm0') define(`M0', `%xmm1') define(`M1', `%xmm2') define(`R', `%xmm3') -define(`ONE', `%xmm4') .file "ghash-update.asm" @@ -52,15 +51,10 @@ define(`ONE', `%xmm4') .text ALIGN(16) PROLOGUE(_nettle_ghash_update) - W64_ENTRY(4, 5) + W64_ENTRY(4, 4) sub $1, BLOCKS movups (XP), X jc .Ldone - C Point to middle of table. - lea 1024(KEY), KEY - movaps X, ONE - pcmpeqd ONE, ONE - psrlq $63, ONE ALIGN(16) .Lblock_loop: @@ -68,22 +62,21 @@ ALIGN(16) movups (SRC), M0 pxor M0, X pxor R, R - mov $-1024, CNT + mov $1008, CNT ALIGN(16) .Loop_bit: - movaps ONE, M0 - pand X, M0 - pcmpeqd ONE, M0 - pshufd $0xaa, M0, M1 - pshufd $0, M0, M0 - psrlq $1, X + movaps X, M0 + psrad $31, M0 + pshufd $0xff, M0, M1 + pshufd $0x55, M0, M0 + psllq $1, X pand (KEY, CNT), M0 pand 1024(KEY, CNT), M1 pxor M0, R pxor M1, R - add $16, CNT - jnz .Loop_bit + sub $16, CNT + jnc .Loop_bit movaps R, X @@ -94,6 +87,6 @@ ALIGN(16) .Ldone: movups X, (XP) mov SRC, %rax - W64_EXIT(4, 5) + W64_EXIT(4, 4) ret EPILOGUE(_nettle_ghash_update) |