[libcxx-commits] [clang] [compiler-rt] [libcxx] Implement soft x87 `long double` for ARM64EC (PR #236406)

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Andarwinux wrote:

Why not just change MinGW x86-64 long double to f64?

1. mingw-w64 indeed has supported -mlong-double-64 some time now.
2. This is compatible with MSVC ABI.
3. This addressed arm64ec interoperability problems.
4. This won't introduce many changes for compilers, both gcc and clang.
5. This also improves performance and makes the abandonment of x87 possible.

Given that long double isn't widely used in the wild, I think this is a better option than working hard to implement f80 emulation in clang.

https://github.com/llvm/llvm-project/pull/236406