diff --git a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
--- a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
+++ b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -5116,6 +5116,7 @@
 
       {6, MVT::v2i8, 6}, // (load 12i8 and) deinterleave into 6 x 2i8
       {6, MVT::v4i8, 14}, // (load 24i8 and) deinterleave into 6 x 4i8
+      {6, MVT::v8i8, 18}, // (load 48i8 and) deinterleave into 6 x 8i8
 
       {6, MVT::v2i16, 13}, // (load 12i16 and) deinterleave into 6 x 2i16
       {6, MVT::v4i16, 9}, // (load 24i16 and) deinterleave into 6 x 4i16
@@ -5169,6 +5170,7 @@
 
       {6, MVT::v2i8, 7},  // interleave 6 x 2i8 into 12i8 (and store)
       {6, MVT::v4i8, 9},  // interleave 6 x 4i8 into 24i8 (and store)
+      {6, MVT::v8i8, 16},  // interleave 6 x 8i8 into 48i8 (and store)
 
       {6, MVT::v2i16, 10},  // interleave 6 x 2i16 into 12i16 (and store)
       {6, MVT::v4i16, 15},  // interleave 6 x 4i16 into 24i16 (and store)
diff --git a/llvm/test/Analysis/CostModel/X86/interleaved-load-i8-stride-6.ll b/llvm/test/Analysis/CostModel/X86/interleaved-load-i8-stride-6.ll
--- a/llvm/test/Analysis/CostModel/X86/interleaved-load-i8-stride-6.ll
+++ b/llvm/test/Analysis/CostModel/X86/interleaved-load-i8-stride-6.ll
@@ -28,7 +28,7 @@
 ; AVX2: LV: Found an estimated cost of 1 for VF 1 For instruction:   %v0 = load i8, i8* %in0, align 1
 ; AVX2: LV: Found an estimated cost of 9 for VF 2 For instruction:   %v0 = load i8, i8* %in0, align 1
 ; AVX2: LV: Found an estimated cost of 17 for VF 4 For instruction:   %v0 = load i8, i8* %in0, align 1
-; AVX2: LV: Found an estimated cost of 114 for VF 8 For instruction:   %v0 = load i8, i8* %in0, align 1
+; AVX2: LV: Found an estimated cost of 20 for VF 8 For instruction:   %v0 = load i8, i8* %in0, align 1
 ; AVX2: LV: Found an estimated cost of 243 for VF 16 For instruction:   %v0 = load i8, i8* %in0, align 1
 ; AVX2: LV: Found an estimated cost of 498 for VF 32 For instruction:   %v0 = load i8, i8* %in0, align 1
 ;
diff --git a/llvm/test/Analysis/CostModel/X86/interleaved-store-i8-stride-6.ll b/llvm/test/Analysis/CostModel/X86/interleaved-store-i8-stride-6.ll
--- a/llvm/test/Analysis/CostModel/X86/interleaved-store-i8-stride-6.ll
+++ b/llvm/test/Analysis/CostModel/X86/interleaved-store-i8-stride-6.ll
@@ -28,7 +28,7 @@
 ; AVX2: LV: Found an estimated cost of 1 for VF 1 For instruction:   store i8 %v5, i8* %out5, align 1
 ; AVX2: LV: Found an estimated cost of 10 for VF 2 For instruction:   store i8 %v5, i8* %out5, align 1
 ; AVX2: LV: Found an estimated cost of 12 for VF 4 For instruction:   store i8 %v5, i8* %out5, align 1
-; AVX2: LV: Found an estimated cost of 101 for VF 8 For instruction:   store i8 %v5, i8* %out5, align 1
+; AVX2: LV: Found an estimated cost of 18 for VF 8 For instruction:   store i8 %v5, i8* %out5, align 1
 ; AVX2: LV: Found an estimated cost of 201 for VF 16 For instruction:   store i8 %v5, i8* %out5, align 1
 ; AVX2: LV: Found an estimated cost of 498 for VF 32 For instruction:   store i8 %v5, i8* %out5, align 1
 ;