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

[Phoebe Wang via cfe-commits]

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@@ -1035,10 +1077,11 @@ _mm_srli_pi32(__m64 __m, int __count)
 /// \param __count
 ///    A 64-bit integer vector interpreted as a single 64-bit integer.
 /// \returns A 64-bit integer vector containing the right-shifted value.
-static __inline__ __m64 __DEFAULT_FN_ATTRS
+static __inline__ __m64 __DEFAULT_FN_ATTRS_SSE2
 _mm_srl_si64(__m64 __m, __m64 __count)
 {
-    return (__m64)__builtin_ia32_psrlq((__v1di)__m, __count);
+    return __trunc64(__builtin_ia32_psrlq128((__v2di)__anyext128(__m),
+                                             __anyext128(__count)));
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phoebewang wrote:

ditto.

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