[WebAssembly] LLVM IR add does not compile to wrapping Wasm

[yowl]

https://godbolt.org/z/6ETzMh11h

This LLVM uses add to add -4 to a symbol, but the Wasm, as I read it, has the $base as -4 and $offset as the symbol, this will not wrap whereas the semantic for LLVM add should wrap.

Compiling with O1 creates the correct Wasm:

https://godbolt.org/z/5W8rEMs5q

[llvmbot]

@llvm/issue-subscribers-backend-webassembly

Author: None (yowl)

https://godbolt.org/z/6ETzMh11h

This LLVM uses add to add -4 to a symbol, but the Wasm, as I read it, has the $base as -4 and $offset as the symbol, this will not wrap whereas the semantic for LLVM add should wrap.

Compiling with O1 creates the correct Wasm:

https://godbolt.org/z/5W8rEMs5q