fixup! simplify getMinimumVLForUser

Author: michaelmaitland

llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp

@@ -1079,11 +1079,7 @@ RISCVVLOptimizer::getMinimumVLForUser(MachineOperand &UserOp) {
            "Expect LMUL 1 register class for vector as scalar operands!");
     LLVM_DEBUG(dbgs() << "    Used this operand as a scalar operand\n");
 
-    unsigned VLOpNum = RISCVII::getVLOpNum(Desc);
-    const MachineOperand &VLOp = UserMI.getOperand(VLOpNum);
-    return VLOp.isReg() || (VLOp.isImm() && VLOp.getImm() != 0)
-               ? MachineOperand::CreateImm(1)
-               : VLOp;
+    return MachineOperand::CreateImm(1);
   }
 
   unsigned VLOpNum = RISCVII::getVLOpNum(Desc);

llvm/test/CodeGen/RISCV/rvv/vl-opt-op-info.mir

@@ -1160,7 +1160,7 @@ name: vred_both_vl0
 body: |
   bb.0:
     ; CHECK-LABEL: name: vred_both_vl0
-    ; CHECK: %x:vr = PseudoVADD_VV_M1 $noreg, $noreg, $noreg, 0, 3 /* e8 */, 0 /* tu, mu */
+    ; CHECK: %x:vr = PseudoVADD_VV_M1 $noreg, $noreg, $noreg, 1, 3 /* e8 */, 0 /* tu, mu */
     ; CHECK-NEXT: %y:vr = PseudoVREDSUM_VS_M1_E8 $noreg, $noreg, %x, 0, 3 /* e8 */, 0 /* tu, mu */
     ; CHECK-NEXT: %z:vr = PseudoVADD_VV_M1 $noreg, %x, $noreg, 0, 3 /* e8 */, 0 /* tu, mu */
     %x:vr = PseudoVADD_VV_M1 $noreg, $noreg, $noreg, -1, 3 /* e8 */, 0