[clang] [llvm] [RISCV][P-ext] Support Packed Load (PR #223313)

[Sam Elliott via cfe-commits]

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@@ -328,6 +328,12 @@ typedef uint32_t uint32x2_t __attribute__((__vector_size__(8)));
     return __v;                                                                \
   }
 
+#define __packed_load(name, ty, elt_ty)                                        \
+  static __inline__ ty __DEFAULT_FN_ATTRS __riscv_##name(elt_ty *__p) {        \
+    typedef ty __attribute__((__aligned__(1))) ua_ty;                          \
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lenary wrote:

I'm probably being dim - why is this needed, what is it doing?

https://github.com/llvm/llvm-project/pull/223313