[compiler-rt] [compiler-rt] Add missing carry to 128x128->256 wide multiply (PR #97257)

[Trevor Gross via llvm-commits]

tgross35 wrote:

> I've tested the fix works locally. I've also added a test to this PR for the fix, although I can't run it locally as the `__multf3` test is only run on platforms where `long double` is f128.

All these tests probably should change to use __float128 with the `q` literal suffix at some point

https://github.com/llvm/llvm-project/pull/97257