[clang] [llvm] [RISCV][P-ext] Support Packed Element Extract (PR #221565)

[Hongyu Chen via llvm-commits]

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@@ -0,0 +1,30 @@
+// REQUIRES: riscv-registered-target
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XChy wrote:

I moved the test to Sema. It still needs riscv-target because `riscv_packed_simd.h` contains RISC-V-specific builtins.

https://github.com/llvm/llvm-project/pull/221565