Index: lib/Target/AMDGPU/AMDGPUISelLowering.cpp =================================================================== --- lib/Target/AMDGPU/AMDGPUISelLowering.cpp +++ lib/Target/AMDGPU/AMDGPUISelLowering.cpp @@ -3055,7 +3055,7 @@ // Equivalent of above for accessing the high element of a vector as an // integer operation. // trunc (srl (bitcast (build_vector x, y))), 16 -> trunc (bitcast y) - if (Src.getOpcode() == ISD::SRL) { + if (Src.getOpcode() == ISD::SRL && !VT.isVector()) { if (auto K = isConstOrConstSplat(Src.getOperand(1))) { if (2 * K->getZExtValue() == Src.getValueType().getScalarSizeInBits()) { SDValue BV = stripBitcast(Src.getOperand(0)); Index: test/CodeGen/AMDGPU/trunc-combine.ll =================================================================== --- test/CodeGen/AMDGPU/trunc-combine.ll +++ test/CodeGen/AMDGPU/trunc-combine.ll @@ -53,3 +53,30 @@ %add = add i16 %trunc, 4 ret i16 %add } + +; GCN-LABEL: {{^}}truncate_high_elt_extract_vector: +; GCN: s_load_dword s +; GCN: s_load_dword s +; GCN: s_sext_i32_i16 +; GCN: s_sext_i32_i16 +; GCN: v_mul_i32_i24 +; GCN: v_lshrrev_b32_e32 +define amdgpu_kernel void @truncate_high_elt_extract_vector(<2 x i16> addrspace(1)* nocapture readonly %arg, <2 x i16> addrspace(1)* nocapture readonly %arg1, <2 x i16> addrspace(1)* nocapture %arg2) local_unnamed_addr { +bb: + %tmp = getelementptr inbounds <2 x i16>, <2 x i16> addrspace(1)* %arg, i64 undef + %tmp3 = load <2 x i16>, <2 x i16> addrspace(1)* %tmp, align 4 + %tmp4 = getelementptr inbounds <2 x i16>, <2 x i16> addrspace(1)* %arg1, i64 undef + %tmp5 = load <2 x i16>, <2 x i16> addrspace(1)* %tmp4, align 4 + %tmp6 = sext <2 x i16> %tmp3 to <2 x i32> + %tmp7 = sext <2 x i16> %tmp5 to <2 x i32> + %tmp8 = extractelement <2 x i32> %tmp6, i64 0 + %tmp9 = extractelement <2 x i32> %tmp7, i64 0 + %tmp10 = mul nsw i32 %tmp9, %tmp8 + %tmp11 = insertelement <2 x i32> undef, i32 %tmp10, i32 0 + %tmp12 = insertelement <2 x i32> %tmp11, i32 undef, i32 1 + %tmp13 = lshr <2 x i32> %tmp12, + %tmp14 = trunc <2 x i32> %tmp13 to <2 x i16> + %tmp15 = getelementptr inbounds <2 x i16>, <2 x i16> addrspace(1)* %arg2, i64 undef + store <2 x i16> %tmp14, <2 x i16> addrspace(1)* %tmp15, align 4 + ret void +}