search for: getopcodewithsubtypes

Hi Chris, Would it be better to split add into multiple opcodes instead of using SubclassData bits? Compare this: switch (I->getOpcode()) { case Instruction::Add: { switch (cast<Add>(I)->getOverflowBehavior()) { case AddInstruction::Wrapping: // ... case AddInstruction::UndefinedSigned: // ... case

...of how we don't actually need opcode bits or concrete classes to make isa "work". It would be a nice cleanup to add new "pseudo instruction" classes like IntrinsicInst for all the arithmetic anyway. If the switch case really does become important, we can just add a getOpcodeWithSubtypes() method that returns a new flattened enum. > -Chris

Edwin was asking about how we should handle PR3328, how we should make GEP respect -fwrapv etc. I wrote up some thoughts here if anyone is interested: http://nondot.org/sabre/LLVMNotes/IntegerOverflow.txt -Chris