[llvm] [WebAssembly] Constant fold wasm.dot (PR #149619)

[Andrew Lazarev via llvm-commits]

alazarev wrote:

It breaks ubsan bot:
https://lab.llvm.org/buildbot/#/builders/25/builds/10523

Earlier today the failure was hidden by another breakage that is fixed now.

https://github.com/llvm/llvm-project/pull/149619