[clang] [X86] Allow PSHUFD/PSHUFLW/PSHUFW intrinsics in constexpr. (PR #161210)

[Simon Pilgrim via cfe-commits]

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@@ -39,14 +39,19 @@ typedef short __v8hi __attribute__((__vector_size__(16)));
 typedef char __v16qi __attribute__((__vector_size__(16)));
 
 /* Define the default attributes for the functions in this file. */
+#define __DEFAULT_FN_ATTRS_MMX \
+  __attribute__((__always_inline__, __nodebug__, __target__("mmx")))
+
 #define __DEFAULT_FN_ATTRS_SSE2                                                \
   __attribute__((__always_inline__, __nodebug__, __target__("sse2"),           \
                  __min_vector_width__(128)))
 
 #if defined(__cplusplus) && (__cplusplus >= 201103L)
 #define __DEFAULT_FN_ATTRS_SSE2_CONSTEXPR __DEFAULT_FN_ATTRS_SSE2 constexpr
+#define __DEFAULT_FN_ATTRS_MMX_CONSTEXPR __DEFAULT_FN_ATTRS_MMX constexpr
 #else
 #define __DEFAULT_FN_ATTRS_SSE2_CONSTEXPR __DEFAULT_FN_ATTRS_SSE2
+#define __DEFAULT_FN_ATTRS_MMX_CONSTEXPR __DEFAULT_FN_ATTRS_MMX 
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RKSimon wrote:

remove all this - there should be no changes to the headers

https://github.com/llvm/llvm-project/pull/161210