[clang] [Clang][SME] Add IsStreamingOrSVE2p1 (PR #75958)

[Kerry McLaughlin via cfe-commits]

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@@ -11,10 +11,16 @@
 // RUN: %clang_cc1 -fclang-abi-compat=latest -triple aarch64-none-linux-gnu -target-feature +sve2p1 \
 // RUN:   -S -disable-O0-optnone -Werror -Wall -o /dev/null %s
 // RUN: %clang_cc1 -fclang-abi-compat=latest -triple aarch64-none-linux-gnu -target-feature +sme2 -target-feature +sve \
-// RUN:   -S -disable-O0-optnone -Werror -Wall -o /dev/null %s
+// RUN:   -S -DTEST_SME2 -disable-O0-optnone -Werror -Wall -o /dev/null %s
 
 #include <arm_sve.h>
 
+#ifndef TEST_SME2
+#define ATTR
+#else
+#define ATTR __arm_streaming
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kmclaughlin-arm wrote:

I think this should be __arm_streaming_compatible?

https://github.com/llvm/llvm-project/pull/75958