[LLVMdev] replace the intrinsic call by a C function call

[Tim Northover]

> Is there anyway to replace a intrinsic call by a “normal” function call?

An LLVM IR pass could do it easily, or XYZISelLowering.cpp a bit more
messily once you get that far (AArch64 does something similar in
LowerFSINCOS).

If it's a custom intrinsic though, you could consider emitting the
call in the first place. You don't *have* to use an intrinsic for
functions with special handling: most of the libm functions don't have
special intrinsics in LLVM for example, but do get special treatment
elsewhere.

I suppose I'd make the decision based on whether the front-end easily
knew the final call, or whether it was sometimes a real instruction
(in some subtarget).

Cheers.

Tim.