diff --git a/cipher/benchmark_test.go b/cipher/benchmark_test.go
index f2eec0e..e373a4e 100644
--- a/cipher/benchmark_test.go
+++ b/cipher/benchmark_test.go
@@ -32,7 +32,7 @@ func BenchmarkSM4CBCEncrypt1K(b *testing.B) {
 	benchmarkCBCEncrypt1K(b, c)
 }
 
-func benchmarkSM4CBCDecrypt1K(b *testing.B, block cipher.Block) {
+func benchmarkCBCDecrypt1K(b *testing.B, block cipher.Block) {
 	buf := make([]byte, 1024)
 	b.SetBytes(int64(len(buf)))
 
@@ -46,13 +46,13 @@ func benchmarkSM4CBCDecrypt1K(b *testing.B, block cipher.Block) {
 func BenchmarkAESCBCDecrypt1K(b *testing.B) {
 	var key [16]byte
 	c, _ := aes.NewCipher(key[:])
-	benchmarkSM4CBCDecrypt1K(b, c)
+	benchmarkCBCDecrypt1K(b, c)
 }
 
 func BenchmarkSM4CBCDecrypt1K(b *testing.B) {
 	var key [16]byte
 	c, _ := sm4.NewCipher(key[:])
-	benchmarkSM4CBCDecrypt1K(b, c)
+	benchmarkCBCDecrypt1K(b, c)
 }
 
 func benchmarkStream(b *testing.B, block cipher.Block, mode func(cipher.Block, []byte) cipher.Stream, buf []byte) {
diff --git a/sm2/sm2.go b/sm2/sm2.go
index c770c41..12d0e69 100644
--- a/sm2/sm2.go
+++ b/sm2/sm2.go
@@ -883,7 +883,7 @@ type sm2Curve struct {
 	nMinus2  []byte
 }
 
-// pointFromAffine is used to convert the PublicKey to a nistec Point.
+// pointFromAffine is used to convert the PublicKey to a sm2 Point.
 func (curve *sm2Curve) pointFromAffine(x, y *big.Int) (p *_sm2ec.SM2P256Point, err error) {
 	bitSize := curve.curve.Params().BitSize
 	// Reject values that would not get correctly encoded.
@@ -902,7 +902,7 @@ func (curve *sm2Curve) pointFromAffine(x, y *big.Int) (p *_sm2ec.SM2P256Point, e
 	return curve.newPoint().SetBytes(buf)
 }
 
-// pointToAffine is used to convert a nistec Point to a PublicKey.
+// pointToAffine is used to convert a sm2 Point to a PublicKey.
 func (curve *sm2Curve) pointToAffine(p *_sm2ec.SM2P256Point) (x, y *big.Int, err error) {
 	out := p.Bytes()
 	if len(out) == 1 && out[0] == 0 {
diff --git a/sm4/aesni_amd64.h b/sm4/aesni_amd64.h
index 099ce5c..67a9bc0 100644
--- a/sm4/aesni_amd64.h
+++ b/sm4/aesni_amd64.h
@@ -209,7 +209,7 @@ GLOBL fk_mask<>(SB), RODATA, $16
 // - t2: 128 bits register for data
 // - t3: 128 bits register for data
 #define SM4_SINGLE_ROUND(index, RK, IND, x, y, z, t0, t1, t2, t3)  \ 
-	PINSRD $0, (index * 4)(RK)(IND*1), x;             \
+	MOVL (index * 4)(RK)(IND*1), x;                   \
 	PXOR t1, x;                                       \
 	PXOR t2, x;                                       \
 	PXOR t3, x;                                       \
diff --git a/sm4/asm_amd64.s b/sm4/asm_amd64.s
index 1d84433..b1f66bb 100644
--- a/sm4/asm_amd64.s
+++ b/sm4/asm_amd64.s
@@ -338,7 +338,7 @@ TEXT ·encryptBlockAsm(SB),NOSPLIT,$0
 	MOVQ dst+8(FP), BX
 	MOVQ src+16(FP), DX
   
-	MOVUPS (DX), t0
+	MOVOU (DX), t0
 	PSHUFB flip_mask<>(SB), t0
 	PSHUFD $1, t0, t1
 	PSHUFD $2, t0, t2
@@ -356,14 +356,12 @@ loop:
 		CMPL CX, $4*32
 		JB loop
 
-	PEXTRD $0, t2, R8
-	PINSRD $1, R8, t3
-	PEXTRD $0, t1, R8
-	PINSRD $2, R8, t3
-	PEXTRD $0, t0, R8
-	PINSRD $3, R8, t3
-	PSHUFB flip_mask<>(SB), t3
-	MOVUPS t3, (BX)
+	PALIGNR $4, t3, t3
+	PALIGNR $4, t3, t2
+	PALIGNR $4, t2, t1
+	PALIGNR $4, t1, t0
+	PSHUFB flip_mask<>(SB), t0
+	MOVOU t0, (BX)
 
 done_sm4:
 	RET
diff --git a/sm4/cbc_cipher_asm.go b/sm4/cbc_cipher_asm.go
index 82691ba..b539a4c 100644
--- a/sm4/cbc_cipher_asm.go
+++ b/sm4/cbc_cipher_asm.go
@@ -7,7 +7,6 @@ import (
 	"crypto/cipher"
 
 	"github.com/emmansun/gmsm/internal/alias"
-	"github.com/emmansun/gmsm/internal/subtle"
 )
 
 // Assert that sm4CipherAsm implements the cbcEncAble and cbcDecAble interfaces.
@@ -49,6 +48,9 @@ func (x *cbc) BlockSize() int { return BlockSize }
 //go:noescape
 func encryptBlocksChain(xk *uint32, dst, src []byte, iv *byte)
 
+//go:noescape
+func decryptBlocksChain(xk *uint32, dst, src []byte, iv *byte)
+
 func (x *cbc) CryptBlocks(dst, src []byte) {
 	if len(src)%BlockSize != 0 {
 		panic("cipher: input not full blocks")
@@ -76,19 +78,18 @@ func (x *cbc) CryptBlocks(dst, src []byte) {
 	var temp []byte = make([]byte, x.b.blocksSize)
 	var batchSrc []byte = make([]byte, x.b.blocksSize+BlockSize)
 
+	decKeyPtr := &x.b.dec[0]
 	for start > 0 {
-		x.b.DecryptBlocks(temp, src[start:end])
-		subtle.XORBytes(temp, temp, src[start-BlockSize:end-BlockSize])
-		copy(dst[start:], temp)
+		decryptBlocksChain(decKeyPtr, dst[start:end], src[start:end], &src[start-BlockSize])
 		end = start
 		start -= x.b.blocksSize
 	}
 
 	// Handle remain first blocks
-	copy(batchSrc[BlockSize:], src[:end])
-	x.b.DecryptBlocks(temp, batchSrc[BlockSize:])
 	copy(batchSrc, x.iv)
-	subtle.XORBytes(dst, temp[:end], batchSrc)
+	copy(batchSrc[BlockSize:], src[:end])
+	decryptBlocksChain(decKeyPtr, temp, batchSrc[BlockSize:], &batchSrc[0])
+	copy(dst, temp[:end])
 
 	// Set the new iv to the first block we copied earlier.
 	x.iv, x.tmp = x.tmp, x.iv
diff --git a/sm4/cbc_cipher_asm_amd64.s b/sm4/cbc_cipher_asm_amd64.s
index b52edb0..201a925 100644
--- a/sm4/cbc_cipher_asm_amd64.s
+++ b/sm4/cbc_cipher_asm_amd64.s
@@ -34,7 +34,7 @@ loopSrc:
 		JB done_sm4
 		SUBQ $16, ptxLen
 
-		MOVUPS (ptx), t0
+		MOVOU (ptx), t0
 		PXOR IV, t0
 
 		PSHUFB flip_mask<>(SB), t0
@@ -54,16 +54,14 @@ loopRound:
 			CMPL CX, $4*32
 			JB loopRound
 
-		PEXTRD $0, t2, R8
-		PINSRD $1, R8, t3
-		PEXTRD $0, t1, R8
-		PINSRD $2, R8, t3
-		PEXTRD $0, t0, R8
-		PINSRD $3, R8, t3
-		PSHUFB flip_mask<>(SB), t3
+		PALIGNR $4, t3, t3
+		PALIGNR $4, t3, t2
+		PALIGNR $4, t2, t1
+		PALIGNR $4, t1, t0
+		PSHUFB flip_mask<>(SB), t0
 
-		MOVOU t3, IV
-		MOVUPS t3, (ctx)
+		MOVOU t0, IV
+		MOVOU t0, (ctx)
 
 		LEAQ 16(ptx), ptx
 		LEAQ 16(ctx), ctx
@@ -77,3 +75,162 @@ done_sm4:
 #undef ctx
 #undef ptx
 #undef ptxLen
+
+#define XDWTMP0 Y0
+#define XDWTMP1 Y1
+#define XDWTMP2 Y2
+
+#define XDWORD0 Y4
+#define XDWORD1 Y5
+#define XDWORD2 Y6
+#define XDWORD3 Y7
+
+#define NIBBLE_MASK Y3
+#define X_NIBBLE_MASK X3
+#define BYTE_FLIP_MASK 	Y13 // mask to convert LE -> BE
+
+#define XDWORD Y8
+#define YDWORD Y9
+
+#define XWORD X8
+#define YWORD X9
+
+// SM4 round function, AVX2 version, handle 256 bits
+// t0 ^= tao_l1(t1^t2^t3^xk)
+// parameters:
+// - index: round key index immediate number
+// - x: 256 bits temp register
+// - y: 256 bits temp register
+// - t0: 256 bits register for data as result
+// - t1: 256 bits register for data
+// - t2: 256 bits register for data
+// - t3: 256 bits register for data
+#define AVX2_SM4_ROUND(index, x, y, t0, t1, t2, t3)                                                    \
+	VPBROADCASTD (index * 4)(AX)(CX*1), x;                                                               \
+	VPXOR t1, x, x;                                                                                      \
+	VPXOR t2, x, x;                                                                                      \
+	VPXOR t3, x, x;                                                                                      \
+	AVX2_SM4_TAO_L1(x, y, XDWTMP0, XWORD, YWORD, X_NIBBLE_MASK, NIBBLE_MASK);                            \
+	VPXOR x, t0, t0
+
+// func decryptBlocksChain(xk *uint32, dst, src []byte, iv *byte)
+TEXT ·decryptBlocksChain(SB),NOSPLIT,$0
+	MOVQ xk+0(FP), AX
+	MOVQ dst+8(FP), BX
+	MOVQ src+32(FP), DX
+	MOVQ iv+56(FP), SI
+
+	CMPB ·useAVX2(SB), $1
+	JE   avx2
+
+non_avx2_start:
+	PINSRD $0, 0(DX), t0
+	PINSRD $1, 16(DX), t0
+	PINSRD $2, 32(DX), t0
+	PINSRD $3, 48(DX), t0
+	PSHUFB flip_mask<>(SB), t0
+
+	PINSRD $0, 4(DX), t1
+	PINSRD $1, 20(DX), t1
+	PINSRD $2, 36(DX), t1
+	PINSRD $3, 52(DX), t1
+	PSHUFB flip_mask<>(SB), t1
+
+	PINSRD $0, 8(DX), t2
+	PINSRD $1, 24(DX), t2
+	PINSRD $2, 40(DX), t2
+	PINSRD $3, 56(DX), t2
+	PSHUFB flip_mask<>(SB), t2
+
+	PINSRD $0, 12(DX), t3
+	PINSRD $1, 28(DX), t3
+	PINSRD $2, 44(DX), t3
+	PINSRD $3, 60(DX), t3
+	PSHUFB flip_mask<>(SB), t3
+
+	XORL CX, CX
+
+loop:
+		SM4_ROUND(0, AX, CX, x, y, XTMP6, t0, t1, t2, t3)
+		SM4_ROUND(1, AX, CX, x, y, XTMP6, t1, t2, t3, t0)
+		SM4_ROUND(2, AX, CX, x, y, XTMP6, t2, t3, t0, t1)
+		SM4_ROUND(3, AX, CX, x, y, XTMP6, t3, t0, t1, t2)
+
+		ADDL $16, CX
+		CMPL CX, $4*32
+		JB loop
+
+	PSHUFB flip_mask<>(SB), t3
+	PSHUFB flip_mask<>(SB), t2
+	PSHUFB flip_mask<>(SB), t1
+	PSHUFB flip_mask<>(SB), t0
+
+	SSE_TRANSPOSE_MATRIX(CX, t3, t2, t1, t0, XWORD, YWORD)
+
+	PXOR 0(SI), t3
+	PXOR 16(SI), t2
+	PXOR 32(SI), t1
+	PXOR 48(SI), t0
+
+	MOVUPS t3, 0(BX)
+	MOVUPS t2, 16(BX)
+	MOVUPS t1, 32(BX)
+	MOVUPS t0, 48(BX)
+
+done_sm4:
+	RET
+
+avx2:
+	VBROADCASTI128 nibble_mask<>(SB), NIBBLE_MASK
+
+avx2_8blocks:
+	VMOVDQU 0(DX), XDWORD0
+	VMOVDQU 32(DX), XDWORD1
+	VMOVDQU 64(DX), XDWORD2
+	VMOVDQU 96(DX), XDWORD3
+	VBROADCASTI128 flip_mask<>(SB), BYTE_FLIP_MASK
+
+	// Apply Byte Flip Mask: LE -> BE
+	VPSHUFB BYTE_FLIP_MASK, XDWORD0, XDWORD0
+	VPSHUFB BYTE_FLIP_MASK, XDWORD1, XDWORD1
+	VPSHUFB BYTE_FLIP_MASK, XDWORD2, XDWORD2
+	VPSHUFB BYTE_FLIP_MASK, XDWORD3, XDWORD3
+
+	// Transpose matrix 4 x 4 32bits word
+	TRANSPOSE_MATRIX(XDWORD0, XDWORD1, XDWORD2, XDWORD3, XDWTMP1, XDWTMP2)
+
+	XORL CX, CX
+
+avx2_loop:
+		AVX2_SM4_ROUND(0, XDWORD, YDWORD, XDWORD0, XDWORD1, XDWORD2, XDWORD3)
+		AVX2_SM4_ROUND(1, XDWORD, YDWORD, XDWORD1, XDWORD2, XDWORD3, XDWORD0)
+		AVX2_SM4_ROUND(2, XDWORD, YDWORD, XDWORD2, XDWORD3, XDWORD0, XDWORD1)
+		AVX2_SM4_ROUND(3, XDWORD, YDWORD, XDWORD3, XDWORD0, XDWORD1, XDWORD2)
+
+		ADDL $16, CX
+		CMPL CX, $4*32
+		JB avx2_loop
+
+	// Transpose matrix 4 x 4 32bits word
+	TRANSPOSE_MATRIX(XDWORD0, XDWORD1, XDWORD2, XDWORD3, XDWTMP1, XDWTMP2)
+
+	VBROADCASTI128 bswap_mask<>(SB), BYTE_FLIP_MASK
+	VPSHUFB BYTE_FLIP_MASK, XDWORD0, XDWORD0
+	VPSHUFB BYTE_FLIP_MASK, XDWORD1, XDWORD1
+	VPSHUFB BYTE_FLIP_MASK, XDWORD2, XDWORD2
+	VPSHUFB BYTE_FLIP_MASK, XDWORD3, XDWORD3
+
+	VPXOR 0(SI), XDWORD0, XDWORD0
+	VPXOR 32(SI), XDWORD1, XDWORD1
+	VPXOR 64(SI), XDWORD2, XDWORD2
+	VPXOR 96(SI), XDWORD3, XDWORD3
+
+	VMOVDQU XDWORD0, 0(BX)
+	VMOVDQU XDWORD1, 32(BX)
+	VMOVDQU XDWORD2, 64(BX)
+	VMOVDQU XDWORD3, 96(BX)
+
+
+avx2_sm4_done:
+	VZEROUPPER
+	RET
diff --git a/sm4/cbc_cipher_asm_arm64.s b/sm4/cbc_cipher_asm_arm64.s
index 673e79a..ac85085 100644
--- a/sm4/cbc_cipher_asm_arm64.s
+++ b/sm4/cbc_cipher_asm_arm64.s
@@ -86,3 +86,50 @@ done_sm4:
 #undef ptx
 #undef ptxLen
 #undef rkSave
+
+// func decryptBlocksChain(xk *uint32, dst, src []byte, iv *byte)
+TEXT ·decryptBlocksChain(SB),NOSPLIT,$0
+	LOAD_SM4_AESNI_CONSTS()
+
+	MOVD xk+0(FP), R8
+	MOVD dst+8(FP), R9
+	MOVD src+32(FP), R10
+	MOVD src_len+40(FP), R12
+	MOVD iv+56(FP), R11
+
+
+	VLD1 (R10), [t0.S4, t1.S4, t2.S4, t3.S4]
+	VREV32 t0.B16, t0.B16
+	VREV32 t1.B16, t1.B16
+	VREV32 t2.B16, t2.B16
+	VREV32 t3.B16, t3.B16
+	PRE_TRANSPOSE_MATRIX(t0, t1, t2, t3, x, y, XTMP6, XTMP7)
+
+	VEOR ZERO.B16, ZERO.B16, ZERO.B16
+	EOR R0, R0
+
+encryptBlocksLoop:
+		SM4_ROUND(R8, R19, x, y, XTMP6, t0, t1, t2, t3)
+		SM4_ROUND(R8, R19, x, y, XTMP6, t1, t2, t3, t0)
+		SM4_ROUND(R8, R19, x, y, XTMP6, t2, t3, t0, t1)
+		SM4_ROUND(R8, R19, x, y, XTMP6, t3, t0, t1, t2)
+
+		ADD $16, R0
+		CMP $128, R0
+		BNE encryptBlocksLoop
+
+	TRANSPOSE_MATRIX(t0, t1, t2, t3, x, y, XTMP6, XTMP7)
+	VREV32 t0.B16, t0.B16
+	VREV32 t1.B16, t1.B16
+	VREV32 t2.B16, t2.B16
+	VREV32 t3.B16, t3.B16
+	
+	VLD1 (R11), [V6.S4, V7.S4, V8.S4, V9.S4]
+	
+	VEOR V6.B16, t0.B16, t0.B16
+	VEOR V7.B16, t1.B16, t1.B16
+	VEOR V8.B16, t2.B16, t2.B16
+	VEOR V9.B16, t3.B16, t3.B16
+
+	VST1 [t0.S4, t1.S4, t2.S4, t3.S4], (R9)
+	RET