Use target reg as temp for comparison result

Author: tomeksowi

src/coreclr/jit/codegenriscv64.cpp

@@ -1002,15 +1002,14 @@ void CodeGen::genCodeForIncSaturate(GenTree* tree)
 
     GenTree* operand = tree->gtGetOp1();
     assert(!operand->isContained());
-    regNumber tempReg = internalRegisters.GetSingle(tree);
     // The src must be a register.
     regNumber operandReg = genConsumeReg(operand);
     emitAttr  attr       = emitActualTypeSize(tree);
     assert(EA_SIZE(attr) == EA_PTRSIZE);
-    assert(tempReg != operandReg);
+    noway_assert(targetReg != operandReg); // lifetime of the operand register should have been extended
 
-    GetEmitter()->emitIns_R_R_I(INS_sltiu, attr, tempReg, operandReg, SIZE_T_MAX); // temp = (operand < max) ? 1 : 0;
-    GetEmitter()->emitIns_R_R_I(INS_add, attr, targetReg, operandReg, tempReg);    // target = operand + temp;
+    GetEmitter()->emitIns_R_R_I(INS_sltiu, attr, targetReg, operandReg, SIZE_T_MAX); // temp = (operand < max) ? 1 : 0;
+    GetEmitter()->emitIns_R_R_R(INS_add, attr, targetReg, operandReg, targetReg);    // target = operand + temp;
 
     genProduceReg(tree);
 }

src/coreclr/jit/lsrariscv64.cpp

@@ -790,9 +790,7 @@ int LinearScan::BuildNode(GenTree* tree)
         case GT_INC_SATURATE:
             assert(dstCount == 1);
             srcCount = 1;
-            BuildUse(tree->gtGetOp1());
-            buildInternalIntRegisterDefForNode(tree);
-            buildInternalRegisterUses();
+            setDelayFree(BuildUse(tree->gtGetOp1()));
             BuildDef(tree);
             break;
     } // end switch (tree->OperGet())