- case Instruction::Select: {
- // If either operand of the select is a constant, we can fold the
- // comparison into the select arms, which will cause one to be
- // constant folded and the select turned into a bitwise or.
- Value *Op1 = 0, *Op2 = 0;
- if (LHSI->hasOneUse()) {
- if (Constant *C = dyn_cast<Constant>(LHSI->getOperand(1))) {
- // Fold the known value into the constant operand.
- Op1 = ConstantExpr::getCompare(I.getPredicate(), C, RHSC);
- // Insert a new FCmp of the other select operand.
- Op2 = Builder->CreateFCmp(I.getPredicate(),
- LHSI->getOperand(2), RHSC, I.getName());
- } else if (Constant *C = dyn_cast<Constant>(LHSI->getOperand(2))) {
- // Fold the known value into the constant operand.
- Op2 = ConstantExpr::getCompare(I.getPredicate(), C, RHSC);
- // Insert a new FCmp of the other select operand.
- Op1 = Builder->CreateFCmp(I.getPredicate(), LHSI->getOperand(1),
- RHSC, I.getName());
- }
- }
-
- if (Op1)
- return SelectInst::Create(LHSI->getOperand(0), Op1, Op2);
- break;
- }