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typesllvmllvm-irbitcode

how to create an llvm Type

I'm trying to create a TruncInst with an i8 destination type. However, I can't seem to find an appropriate type constructor when I look here. I expected it should be something simple like:

if (val->getType()->isIntegerTy(32))
{
    TruncInst *ti = new TruncInst(val,new IntegerType(8));
}

But apparently it's not. I'm probably over looking something in the API. Any help is very much appreciated, thanks!

Solution

  • Type::getInt8Ty(getContext()); will get a type for you, assuming that you have a way to get the relevant context.

    You cannot create an IntegerType yourself because LLVM's design says that if two types t1 and t2 are the same (e.g. both are 8-bit integer types) and exist in the same context, then t1==t2. Much LLVM code expects to test for equality using ==.