[llvm] [Windows] Allow legalizing LDEXP_F128 and FREXP_F128 with libcalls (PR #148326)

[Trevor Gross via llvm-commits]

tgross35 wrote:

> SelectionDAGLegalize::expandLdexp has code to expand ldexp inline; do we want to do that? I can see why we might not want to, I guess, since it's a lot of code to generate inline.

Does that expansion apply to f128? I'm having some trouble following back where that gets configured. I'd be a bit surprised if any libm functions for f128 turn into asm, other than trivial ones like abs/copysign.

> I'd prefer to get the libcall names correct before we merge this: ldexpl exists on Windows, and it's the wrong function, so you're turning a crash into a miscompile.

Sounds reasonable, I'll hold off until https://github.com/llvm/llvm-project/pull/148575 then



https://github.com/llvm/llvm-project/pull/148326