diff --git a/clang/include/clang/Basic/BuiltinsWebAssembly.def b/clang/include/clang/Basic/BuiltinsWebAssembly.def
--- a/clang/include/clang/Basic/BuiltinsWebAssembly.def
+++ b/clang/include/clang/Basic/BuiltinsWebAssembly.def
@@ -167,5 +167,10 @@
 TARGET_BUILTIN(__builtin_wasm_fma_f64x2, "V2dV2dV2dV2d", "nc", "relaxed-simd")
 TARGET_BUILTIN(__builtin_wasm_fms_f64x2, "V2dV2dV2dV2d", "nc", "relaxed-simd")
 
+TARGET_BUILTIN(__builtin_wasm_laneselect_i8x16, "V16ScV16ScV16ScV16Sc", "nc", "relaxed-simd")
+TARGET_BUILTIN(__builtin_wasm_laneselect_i16x8, "V8sV8sV8sV8s", "nc", "relaxed-simd")
+TARGET_BUILTIN(__builtin_wasm_laneselect_i32x4, "V4iV4iV4iV4i", "nc", "relaxed-simd")
+TARGET_BUILTIN(__builtin_wasm_laneselect_i64x2, "V2LLiV2LLiV2LLiV2LLi", "nc", "relaxed-simd")
+
 #undef BUILTIN
 #undef TARGET_BUILTIN
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -18308,6 +18308,17 @@
     Function *Callee = CGM.getIntrinsic(IntNo, A->getType());
     return Builder.CreateCall(Callee, {A, B, C});
   }
+  case WebAssembly::BI__builtin_wasm_laneselect_i8x16:
+  case WebAssembly::BI__builtin_wasm_laneselect_i16x8:
+  case WebAssembly::BI__builtin_wasm_laneselect_i32x4:
+  case WebAssembly::BI__builtin_wasm_laneselect_i64x2: {
+    Value *A = EmitScalarExpr(E->getArg(0));
+    Value *B = EmitScalarExpr(E->getArg(1));
+    Value *C = EmitScalarExpr(E->getArg(2));
+    Function *Callee =
+        CGM.getIntrinsic(Intrinsic::wasm_laneselect, A->getType());
+    return Builder.CreateCall(Callee, {A, B, C});
+  }
   default:
     return nullptr;
   }
diff --git a/clang/test/CodeGen/builtins-wasm.c b/clang/test/CodeGen/builtins-wasm.c
--- a/clang/test/CodeGen/builtins-wasm.c
+++ b/clang/test/CodeGen/builtins-wasm.c
@@ -704,3 +704,31 @@
   // WEBASSEMBLY-SAME: <2 x double> %a, <2 x double> %b, <2 x double> %c)
   // WEBASSEMBLY-NEXT: ret
 }
+
+i8x16 laneselect_i8x16(i8x16 a, i8x16 b, i8x16 c) {
+  return __builtin_wasm_laneselect_i8x16(a, b, c);
+  // WEBASSEMBLY: call <16 x i8> @llvm.wasm.laneselect.v16i8(
+  // WEBASSEMBLY-SAME: <16 x i8> %a, <16 x i8> %b, <16 x i8> %c)
+  // WEBASSEMBLY-NEXT: ret
+}
+
+i16x8 laneselect_i16x8(i16x8 a, i16x8 b, i16x8 c) {
+  return __builtin_wasm_laneselect_i16x8(a, b, c);
+  // WEBASSEMBLY: call <8 x i16> @llvm.wasm.laneselect.v8i16(
+  // WEBASSEMBLY-SAME: <8 x i16> %a, <8 x i16> %b, <8 x i16> %c)
+  // WEBASSEMBLY-NEXT: ret
+}
+
+i32x4 laneselect_i32x4(i32x4 a, i32x4 b, i32x4 c) {
+  return __builtin_wasm_laneselect_i32x4(a, b, c);
+  // WEBASSEMBLY: call <4 x i32> @llvm.wasm.laneselect.v4i32(
+  // WEBASSEMBLY-SAME: <4 x i32> %a, <4 x i32> %b, <4 x i32> %c)
+  // WEBASSEMBLY-NEXT: ret
+}
+
+i64x2 laneselect_i64x2(i64x2 a, i64x2 b, i64x2 c) {
+  return __builtin_wasm_laneselect_i64x2(a, b, c);
+  // WEBASSEMBLY: call <2 x i64> @llvm.wasm.laneselect.v2i64(
+  // WEBASSEMBLY-SAME: <2 x i64> %a, <2 x i64> %b, <2 x i64> %c)
+  // WEBASSEMBLY-NEXT: ret
+}
diff --git a/llvm/include/llvm/IR/IntrinsicsWebAssembly.td b/llvm/include/llvm/IR/IntrinsicsWebAssembly.td
--- a/llvm/include/llvm/IR/IntrinsicsWebAssembly.td
+++ b/llvm/include/llvm/IR/IntrinsicsWebAssembly.td
@@ -195,6 +195,11 @@
             [LLVMMatchType<0>, LLVMMatchType<0>, LLVMMatchType<0>],
             [IntrNoMem, IntrSpeculatable]>;
 
+def int_wasm_laneselect :
+  Intrinsic<[llvm_anyvector_ty],
+            [LLVMMatchType<0>, LLVMMatchType<0>, LLVMMatchType<0>],
+            [IntrNoMem, IntrSpeculatable]>;
+
 //===----------------------------------------------------------------------===//
 // Thread-local storage intrinsics
 //===----------------------------------------------------------------------===//
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
--- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
@@ -1344,3 +1344,20 @@
 
 defm "" : SIMDFM<F32x4, 0xaf, 0xb0>;
 defm "" : SIMDFM<F64x2, 0xcf, 0xd0>;
+
+//===----------------------------------------------------------------------===//
+// Laneselect
+//===----------------------------------------------------------------------===//
+
+multiclass SIMDLANESELECT<Vec vec, bits<32> op> {
+  defm LANESELECT_#vec :
+    RELAXED_I<(outs V128:$dst), (ins V128:$a, V128:$b, V128:$c), (outs), (ins),
+              [(set (vec.vt V128:$dst), (int_wasm_laneselect
+                (vec.vt V128:$a), (vec.vt V128:$b), (vec.vt V128:$c)))],
+              vec.prefix#".laneselect\t$dst, $a, $b, $c", vec.prefix#".laneselect", op>;
+}
+
+defm "" : SIMDLANESELECT<I8x16, 0xb2>;
+defm "" : SIMDLANESELECT<I16x8, 0xb3>;
+defm "" : SIMDLANESELECT<I32x4, 0xd2>;
+defm "" : SIMDLANESELECT<I64x2, 0xd3>;
diff --git a/llvm/test/CodeGen/WebAssembly/simd-intrinsics.ll b/llvm/test/CodeGen/WebAssembly/simd-intrinsics.ll
--- a/llvm/test/CodeGen/WebAssembly/simd-intrinsics.ll
+++ b/llvm/test/CodeGen/WebAssembly/simd-intrinsics.ll
@@ -180,6 +180,18 @@
   ret <16 x i8> %res
 }
 
+; CHECK-LABEL: laneselect_v16i8:
+; CHECK-NEXT: .functype laneselect_v16i8 (v128, v128, v128) -> (v128){{$}}
+; CHECK-NEXT: i8x16.laneselect $push[[R:[0-9]+]]=, $0, $1, $2{{$}}
+; CHECK-NEXT: return $pop[[R]]{{$}}
+declare <16 x i8> @llvm.wasm.laneselect.v16i8(<16 x i8>, <16 x i8>, <16 x i8>)
+define <16 x i8> @laneselect_v16i8(<16 x i8> %a, <16 x i8> %b, <16 x i8> %c) {
+  %v = call <16 x i8> @llvm.wasm.laneselect.v16i8(
+    <16 x i8> %a, <16 x i8> %b, <16 x i8> %c
+  )
+  ret <16 x i8> %v
+}
+
 ; ==============================================================================
 ; 8 x i16
 ; ==============================================================================
@@ -334,6 +346,18 @@
   ret <8 x i16> %a
 }
 
+; CHECK-LABEL: laneselect_v8i16:
+; CHECK-NEXT: .functype laneselect_v8i16 (v128, v128, v128) -> (v128){{$}}
+; CHECK-NEXT: i16x8.laneselect $push[[R:[0-9]+]]=, $0, $1, $2{{$}}
+; CHECK-NEXT: return $pop[[R]]{{$}}
+declare <8 x i16> @llvm.wasm.laneselect.v8i16(<8 x i16>, <8 x i16>, <8 x i16>)
+define <8 x i16> @laneselect_v8i16(<8 x i16> %a, <8 x i16> %b, <8 x i16> %c) {
+  %v = call <8 x i16> @llvm.wasm.laneselect.v8i16(
+    <8 x i16> %a, <8 x i16> %b, <8 x i16> %c
+  )
+  ret <8 x i16> %v
+}
+
 ; ==============================================================================
 ; 4 x i32
 ; ==============================================================================
@@ -480,6 +504,18 @@
   ret <4 x i32> %a
 }
 
+; CHECK-LABEL: laneselect_v4i32:
+; CHECK-NEXT: .functype laneselect_v4i32 (v128, v128, v128) -> (v128){{$}}
+; CHECK-NEXT: i32x4.laneselect $push[[R:[0-9]+]]=, $0, $1, $2{{$}}
+; CHECK-NEXT: return $pop[[R]]{{$}}
+declare <4 x i32> @llvm.wasm.laneselect.v4i32(<4 x i32>, <4 x i32>, <4 x i32>)
+define <4 x i32> @laneselect_v4i32(<4 x i32> %a, <4 x i32> %b, <4 x i32> %c) {
+  %v = call <4 x i32> @llvm.wasm.laneselect.v4i32(
+    <4 x i32> %a, <4 x i32> %b, <4 x i32> %c
+  )
+  ret <4 x i32> %v
+}
+
 ; ==============================================================================
 ; 2 x i64
 ; ==============================================================================
@@ -525,6 +561,18 @@
   ret <2 x i64> %a
 }
 
+; CHECK-LABEL: laneselect_v2i64:
+; CHECK-NEXT: .functype laneselect_v2i64 (v128, v128, v128) -> (v128){{$}}
+; CHECK-NEXT: i64x2.laneselect $push[[R:[0-9]+]]=, $0, $1, $2{{$}}
+; CHECK-NEXT: return $pop[[R]]{{$}}
+declare <2 x i64> @llvm.wasm.laneselect.v2i64(<2 x i64>, <2 x i64>, <2 x i64>)
+define <2 x i64> @laneselect_v2i64(<2 x i64> %a, <2 x i64> %b, <2 x i64> %c) {
+  %v = call <2 x i64> @llvm.wasm.laneselect.v2i64(
+    <2 x i64> %a, <2 x i64> %b, <2 x i64> %c
+  )
+  ret <2 x i64> %v
+}
+
 ; ==============================================================================
 ; 4 x f32
 ; ==============================================================================
diff --git a/llvm/test/MC/WebAssembly/simd-encodings.s b/llvm/test/MC/WebAssembly/simd-encodings.s
--- a/llvm/test/MC/WebAssembly/simd-encodings.s
+++ b/llvm/test/MC/WebAssembly/simd-encodings.s
@@ -791,4 +791,16 @@
     # CHECK: f64x2.fms # encoding: [0xfd,0xd0,0x01]
     f64x2.fms
 
+    # CHECK: i8x16.laneselect # encoding: [0xfd,0xb2,0x01]
+    i8x16.laneselect
+
+    # CHECK: i16x8.laneselect # encoding: [0xfd,0xb3,0x01]
+    i16x8.laneselect
+
+    # CHECK: i32x4.laneselect # encoding: [0xfd,0xd2,0x01]
+    i32x4.laneselect
+
+    # CHECK: i64x2.laneselect # encoding: [0xfd,0xd3,0x01]
+    i64x2.laneselect
+
     end_function