[clang] [AArch64][SME2] Add PEXT, PSEL builtins for SME2 (PR #72827)

[Matthew Devereau via cfe-commits]

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@@ -5,6 +5,11 @@
 // RUN: %clang_cc1 -fclang-abi-compat=latest -triple aarch64-none-linux-gnu \
 // RUN:   -target-feature +sve2p1 -S -O1 -Werror -emit-llvm -o - -x c++ %s | FileCheck %s -check-prefix=CPP-CHECK
 // RUN: %clang_cc1 -fclang-abi-compat=latest -triple aarch64-none-linux-gnu -target-feature +sve2p1 -S -disable-O0-optnone -Werror -Wall -o /dev/null %s
+// RUN: %clang_cc1 -fclang-abi-compat=latest -triple aarch64-none-linux-gnu \
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MDevereau wrote:

As per https://github.com/ARM-software/acle/pull/217/files#diff-516526d4a18101dc85300bc2033d0f86dc46c505b7510a7694baabea851aedfaR11352-R11358
should this be `__arm_streaming_compatible` instead of `__arm_streaming` for psel?

https://github.com/llvm/llvm-project/pull/72827