We can fast-path any < 16 byte read if the full message is > 16 bytes,
and shift over by the appropriate amount. Usually we are
reading > 16 bytes, so this should be faster than the READ_PARTIAL
macro introduced in b20209c91e2 for the average case.
Signed-off-by: Dave Watson <davejwat...@fb.com>
---
arch/x86/crypto/aesni-intel_asm.S | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)
diff --git a/arch/x86/crypto/aesni-intel_asm.S
b/arch/x86/crypto/aesni-intel_asm.S
index 398bd2237f..b941952 100644
--- a/arch/x86/crypto/aesni-intel_asm.S
+++ b/arch/x86/crypto/aesni-intel_asm.S
@@ -355,12 +355,37 @@ _zero_cipher_left_\@:
ENCRYPT_SINGLE_BLOCK %xmm0, %xmm1 # Encrypt(K, Yn)
movdqu %xmm0, PBlockEncKey(%arg2)
+ cmp $16, %arg5
+ jge _large_enough_update_\@
+
lea (%arg4,%r11,1), %r10
mov %r13, %r12
READ_PARTIAL_BLOCK %r10 %r12 %xmm2 %xmm1
+ jmp _data_read_\@
+
+_large_enough_update_\@:
+ sub $16, %r11
+ add %r13, %r11
+
+ # receive the last <16 Byte block
+ movdqu (%arg4, %r11, 1), %xmm1
+ sub %r13, %r11
+ add $16, %r11
+
+ lea SHIFT_MASK+16(%rip), %r12
+ # adjust the shuffle mask pointer to be able to shift 16-r13 bytes
+ # (r13 is the number of bytes in plaintext mod 16)
+ sub %r13, %r12
+ # get the appropriate shuffle mask
+ movdqu (%r12), %xmm2
+ # shift right 16-r13 bytes
+ PSHUFB_XMM %xmm2, %xmm1
+
+_data_read_\@:
lea ALL_F+16(%rip), %r12
sub %r13, %r12
+
.ifc \operation, dec
movdqa %xmm1, %xmm2
.endif
--
2.9.5
