[clang] Add SME2 builtins for pfalse and ptrue (PR #71953)

[Matthew Devereau via cfe-commits]

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@@ -15,7 +17,7 @@
 // CPP-CHECK-NEXT:    [[TMP0:%.*]] = tail call target("aarch64.svcount") @llvm.aarch64.sve.ptrue.c8()
 // CPP-CHECK-NEXT:    ret target("aarch64.svcount") [[TMP0]]
 //
-svcount_t test_svptrue_c8(void) {
+svcount_t test_svptrue_c8(void) __arm_streaming_compatible {
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MDevereau wrote:

I've called the `#if` guard `TEST_SME2`, but done

https://github.com/llvm/llvm-project/pull/71953