[clang] [Clang][RISCV] Add P extension reinterpret cast intrinsics (PR #210241)

[Craig Topper via cfe-commits]

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@@ -635,6 +731,7 @@ __packed_psabs(psabs_i16x4, int16x4_t, __builtin_riscv_psabs_i16x4)
 #undef __packed_unzipo4
 #undef __packed_abdsum
 #undef __packed_abdsum_acc
+#undef __packed_preinterpret
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topperc wrote:

should this be `__packed_reinterpret`? Most operations don't have a 'p' after the underscore except psabs and pabs

https://github.com/llvm/llvm-project/pull/210241