diff --git a/bestla/bestla/kernel_avx2.h b/bestla/bestla/kernel_avx2.h
index 308e37aff..a53f5bdc3 100644
--- a/bestla/bestla/kernel_avx2.h
+++ b/bestla/bestla/kernel_avx2.h
@@ -1161,6 +1161,7 @@ inline BTLA_CODE decompress_kblock_s3_s8fp(utils::bit2x4* bit2ptr, utils::bit1x8
   auto head_ignore_num = interleave_n_offset % 128;
   const __m256i lowMask = _mm256_set1_epi8(0x03);
   const __m256i highMask = _mm256_set1_epi8(0x04);
+  const __m256i bit1Mask = _mm256_set1_epi32(0x0F);
   const __m256i bit1Shift_1 = _mm256_set_epi32(28, 24, 20, 16, 12, 8, 4, 0);
   const __m256i bit1Shift_2 = _mm256_set1_epi32((1 << 23) + (1 << 16) + (1 << 9) + (1 << 2));
 
@@ -1170,6 +1171,7 @@ inline BTLA_CODE decompress_kblock_s3_s8fp(utils::bit2x4* bit2ptr, utils::bit1x8
     for (int i = 0; i < 4; i++) {
       auto bit1x32 = _mm256_set1_epi32(bit1_ptr[i]);
       bit1x32 = _mm256_srlv_epi32(bit1x32, bit1Shift_1);
+      bit1x32 = _mm256_and_si256(bit1x32, bit1Mask);
       bit1x32 = _mm256_mullo_epi32(bit1x32, bit1Shift_2);
       bit1x32 = _mm256_and_si256(highMask, bit1x32);
 
diff --git a/bestla/bestla/kernel_jit.h b/bestla/bestla/kernel_jit.h
index 027d263c8..b69d22563 100644
--- a/bestla/bestla/kernel_jit.h
+++ b/bestla/bestla/kernel_jit.h
@@ -259,7 +259,7 @@ class DecompresssS3 {
       void *bit2ptr, *bit1ptr, *dstptr, *tmpbuf;
       int unpack_elt;
       const int8_t lowMask = 3, highMask = 4;
-      const int32_t bit1Shift2 = (1 << 23) + (1 << 16) + (1 << 9) + (1 << 2);
+      const int32_t bit1Mask = 0x0F, bit1Shift2 = (1 << 23) + (1 << 16) + (1 << 9) + (1 << 2);
       const int32_t bit1Shift1[8] = {0, 4, 8, 12, 16, 20, 24, 28};
     };
     typedef long long (*func_t)(params*);
@@ -288,10 +288,12 @@ class DecompresssS3 {
         xor_(reg_iter, reg_iter);
         Xbyak::Ymm lowMask = ymm15;
         Xbyak::Ymm highMask = ymm14;
-        Xbyak::Ymm bit1Shift1 = ymm13;
-        Xbyak::Ymm bit1Shift2 = ymm12;
+        Xbyak::Ymm bit1Mask = ymm13;
+        Xbyak::Ymm bit1Shift1 = ymm12;
+        Xbyak::Ymm bit1Shift2 = ymm11;
         vpbroadcastb(lowMask, byte[parambase + OFFSET(lowMask)]);
         vpbroadcastb(highMask, byte[parambase + OFFSET(highMask)]);
+        vpbroadcastd(bit1Mask, dword[parambase + OFFSET(bit1Mask)]);
         vpbroadcastd(bit1Shift2, dword[parambase + OFFSET(bit1Shift2)]);
         vmovdqu(bit1Shift1, ptr[parambase + OFFSET(bit1Shift1)]);
         mov(reg_bit1ptr, ptr[parambase + OFFSET(bit1ptr)]);
@@ -304,6 +306,7 @@ class DecompresssS3 {
         for (int i = 0; i < 4; i++) {
           vpbroadcastd(Xbyak::Ymm(i), dword[reg_bit1ptr + 4 * i]);
           vpsrlvd(Xbyak::Ymm(i), Xbyak::Ymm(i), bit1Shift1);  // todo : check m256
+          vpand(Xbyak::Ymm(i), Xbyak::Ymm(i), bit1Mask);
           vpmulld(Xbyak::Ymm(i), Xbyak::Ymm(i), bit1Shift2);
           vpand(Xbyak::Ymm(i), Xbyak::Ymm(i), highMask);
           vpsrlw(Xbyak::Ymm(4 + i), bit2_data, 2 * i);
@@ -328,6 +331,27 @@ class DecompresssS3 {
             vcvtdq2ps(Xbyak::Ymm(4 + i), Xbyak::Ymm(4 + i));
             vmovups(ptr[reg_dst + 4 * (32 * i + 16)], Xbyak::Ymm(i));
             vmovups(ptr[reg_dst + 4 * (32 * i + 24)], Xbyak::Ymm(4 + i));
+
+            // vpmovsxbd(Xbyak::Ymm(4 + i), Xbyak::Xmm(i));
+            // vcvtdq2ps(Xbyak::Ymm(4 + i), Xbyak::Ymm(4 + i));
+            // vmovups(ptr[reg_dst + 4 * (32 * i + 0)], Xbyak::Ymm(4 + i));
+
+            // vextracti128(Xbyak::Xmm(4 + i), Xbyak::Ymm(i), 1);
+            // vpmovsxbd(Xbyak::Ymm(4 + i), Xbyak::Xmm(4 + i));
+            // vcvtdq2ps(Xbyak::Ymm(4 + i), Xbyak::Ymm(4 + i));
+            // vmovups(ptr[reg_dst + 4 * (32 * i + 16)], Xbyak::Ymm(4 + i));
+
+            // vpsrldq(Xbyak::Ymm(i), Xbyak::Ymm(i), 8);
+
+            // vpmovsxbd(Xbyak::Ymm(4 + i), Xbyak::Xmm(i));
+            // vcvtdq2ps(Xbyak::Ymm(4 + i), Xbyak::Ymm(4 + i));
+            // vmovups(ptr[reg_dst + 4 * (32 * i + 8)], Xbyak::Ymm(4 + i));
+
+            // vextracti128(Xbyak::Xmm(4 + i), Xbyak::Ymm(i), 1);
+            // vpmovsxbd(Xbyak::Ymm(4 + i), Xbyak::Xmm(4 + i));
+            // vcvtdq2ps(Xbyak::Ymm(4 + i), Xbyak::Ymm(4 + i));
+            // vmovups(ptr[reg_dst + 4 * (32 * i + 24)], Xbyak::Ymm(4 + i));
+
           } else {
             assert(0);
           }