[llvm] [DAG][ARM] computeKnownBitsForTargetNode - add handling for ARMISD VORRIMM\VBICIMM nodes (PR #149494)

[Simon Pilgrim via llvm-commits]

================
@@ -20106,6 +20106,31 @@ void ARMTargetLowering::computeKnownBitsForTargetNode(const SDValue Op,
     Known = KnownOp0.intersectWith(KnownOp1);
     break;
   }
+  case ARMISD::VORRIMM: {
+    KnownBits KnownLHS = DAG.computeKnownBits(Op.getOperand(0), Depth + 1);
+
+    unsigned Encoded = Op.getConstantOperandVal(1);
+    unsigned ElemSize = Op.getValueType().getScalarSizeInBits();
+    uint64_t DecodedVal = ARM_AM::decodeVMOVModImm(Encoded, ElemSize);
+    APInt Imm(Known.getBitWidth(), DecodedVal);
----------------
RKSimon wrote:

`APInt Imm(ElemSize, DecodedVal);`

https://github.com/llvm/llvm-project/pull/149494