else
llvm_unreachable("shuffle vector mask references neither vector operand?");
- return DAG.getNode(MipsISD::VSHF, DL, ResTy, MaskVec, Op0, Op1);
+ // VECTOR_SHUFFLE concatenates the vectors in an vectorwise fashion.
+ // <0b00, 0b01> + <0b10, 0b11> -> <0b00, 0b01, 0b10, 0b11>
+ // VSHF concatenates the vectors in a bitwise fashion:
+ // <0b00, 0b01> + <0b10, 0b11> ->
+ // 0b0100 + 0b1110 -> 0b01001110
+ // <0b10, 0b11, 0b00, 0b01>
+ // We must therefore swap the operands to get the correct result.
+ return DAG.getNode(MipsISD::VSHF, DL, ResTy, MaskVec, Op1, Op0);
}
// Lower VECTOR_SHUFFLE into one of a number of instructions depending on the
%3 = shufflevector <16 x i8> %1, <16 x i8> %2, <16 x i32> <i32 17, i32 24, i32 25, i32 18, i32 19, i32 20, i32 28, i32 19, i32 1, i32 8, i32 9, i32 2, i32 3, i32 4, i32 12, i32 3>
; CHECK-DAG: addiu [[PTR_A:\$[0-9]+]], {{.*}}, %lo($
; CHECK-DAG: ld.b [[R3:\$w[0-9]+]], 0([[PTR_A]])
- ; CHECK-DAG: vshf.b [[R3]], [[R1]], [[R2]]
+ ; The concatenation step of vshf is bitwise not vectorwise so we must reverse
+ ; the operands to get the right answer.
+ ; CHECK-DAG: vshf.b [[R3]], [[R2]], [[R1]]
store <16 x i8> %3, <16 x i8>* %c
; CHECK-DAG: st.b [[R3]], 0($4)
%3 = shufflevector <8 x i16> %1, <8 x i16> %2, <8 x i32> <i32 1, i32 8, i32 9, i32 2, i32 3, i32 4, i32 12, i32 3>
; CHECK-DAG: addiu [[PTR_A:\$[0-9]+]], {{.*}}, %lo($
; CHECK-DAG: ld.h [[R3:\$w[0-9]+]], 0([[PTR_A]])
- ; CHECK-DAG: vshf.h [[R3]], [[R1]], [[R2]]
+ ; The concatenation step of vshf is bitwise not vectorwise so we must reverse
+ ; the operands to get the right answer.
+ ; CHECK-DAG: vshf.h [[R3]], [[R2]], [[R1]]
store <8 x i16> %3, <8 x i16>* %c
; CHECK-DAG: st.h [[R3]], 0($4)
%3 = shufflevector <4 x i32> %1, <4 x i32> %2, <4 x i32> <i32 1, i32 5, i32 6, i32 4>
; CHECK-DAG: addiu [[PTR_A:\$[0-9]+]], {{.*}}, %lo($
; CHECK-DAG: ld.w [[R3:\$w[0-9]+]], 0([[PTR_A]])
- ; CHECK-DAG: vshf.w [[R3]], [[R1]], [[R2]]
+ ; The concatenation step of vshf is bitwise not vectorwise so we must reverse
+ ; the operands to get the right answer.
+ ; CHECK-DAG: vshf.w [[R3]], [[R2]], [[R1]]
store <4 x i32> %3, <4 x i32>* %c
; CHECK-DAG: st.w [[R3]], 0($4)
%3 = shufflevector <2 x i64> %1, <2 x i64> %2, <2 x i32> <i32 1, i32 2>
; CHECK-DAG: addiu [[PTR_A:\$[0-9]+]], {{.*}}, %lo($
; CHECK-DAG: ld.d [[R3:\$w[0-9]+]], 0([[PTR_A]])
- ; CHECK-DAG: vshf.d [[R3]], [[R1]], [[R2]]
+ ; The concatenation step of vshf is bitwise not vectorwise so we must reverse
+ ; the operands to get the right answer.
+ ; CHECK-DAG: vshf.d [[R3]], [[R2]], [[R1]]
store <2 x i64> %3, <2 x i64>* %c
; CHECK-DAG: st.d [[R3]], 0($4)