Optimize away one of the tbl instructions in the decryption path,
which turns out to be unnecessary.

Signed-off-by: Ard Biesheuvel <ard.biesheu...@linaro.org>
---
 arch/arm64/crypto/aes-modes.S | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/crypto/aes-modes.S b/arch/arm64/crypto/aes-modes.S
index 2879f030a749..38cd5a2091a8 100644
--- a/arch/arm64/crypto/aes-modes.S
+++ b/arch/arm64/crypto/aes-modes.S
@@ -293,12 +293,11 @@ AES_ENTRY(aes_cbc_cts_decrypt)
        ld1             {v5.16b}, [x5]                  /* get iv */
        dec_prepare     w3, x2, x6
 
-       tbl             v2.16b, {v1.16b}, v4.16b
        decrypt_block   v0, w3, x2, x6, w7
-       eor             v2.16b, v2.16b, v0.16b
+       tbl             v2.16b, {v0.16b}, v3.16b
+       eor             v2.16b, v2.16b, v1.16b
 
        tbx             v0.16b, {v1.16b}, v4.16b
-       tbl             v2.16b, {v2.16b}, v3.16b
        decrypt_block   v0, w3, x2, x6, w7
        eor             v0.16b, v0.16b, v5.16b          /* xor with iv */
 
-- 
2.17.1

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