[clang] [llvm] [openmp] [openmp][WebAssembly] add support for wasm64 (PR #181669)

[Andrew Brown via cfe-commits]

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@@ -155,7 +155,7 @@ endif()
 # with either the Emscripten or wasi-threads flavor ends up using the pthreads
 # interface in a WebAssembly-compiled libc; CMake does not yet know how to
 # detect this.
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abrown wrote:

Glad to see you are picking this up! It's been a long while since I thought about this, so I may not be of too much help here: I would say (and you may already know) that eons ago wasi-sdk relied on wasi-threads, which matche the "instance per thread" approach in Emscripten. But wasi-sdk over time moved to using components and wasi-threads was abandoned. Perhaps when I added this it was protecting against some incompatibility related to this? But it's been too long so I would just say go with whatever makes sense today.

https://github.com/llvm/llvm-project/pull/181669