[clang] [llvm] Clang: convert `__m64` intrinsics to unconditionally use SSE2 instead of MMX. (PR #96540)

[Simon Pilgrim via llvm-commits]

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@@ -21,10 +21,29 @@ typedef int __v2si __attribute__((__vector_size__(8)));
 typedef short __v4hi __attribute__((__vector_size__(8)));
 typedef char __v8qi __attribute__((__vector_size__(8)));
 
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RKSimon wrote:

Add a deprecation message if SSE2 is not defined or just rely on the __DEFAULT_FN_ATTRS_SSE2 function attribute error message?

https://github.com/llvm/llvm-project/pull/96540