[clang] [llvm] Add SME2 builtins for zero { zt0 } (PR #72274)

[Sander de Smalen via cfe-commits]

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@@ -0,0 +1,23 @@
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py
+
+// REQUIRES: aarch64-registered-target
+
+// RUN: %clang_cc1 -triple aarch64-none-linux-gnu -target-feature +sme2 -S -disable-O0-optnone -Werror -Wall -emit-llvm -o - %s | opt -S -p mem2reg,instcombine,tailcallelim | FileCheck %s
+// RUN: %clang_cc1 -triple aarch64-none-linux-gnu -target-feature +sme2 -S -disable-O0-optnone -Werror -Wall -emit-llvm -o - -x c++ %s | opt -S -p mem2reg,instcombine,tailcallelim | FileCheck %s -check-prefix=CPP-CHECK
+// RUN: %clang_cc1 -triple aarch64-none-linux-gnu -target-feature +sme2 -S -disable-O0-optnone -Werror -Wall -o /dev/null %s
+
+#include <arm_sme_draft_spec_subject_to_change.h>
+
+// CHECK-LABEL: @test_svzero_zt(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    tail call void @llvm.aarch64.sme.zero.zt(i32 0)
+// CHECK-NEXT:    ret void
+//
+// CPP-CHECK-LABEL: @_Z14test_svzero_ztv(
+// CPP-CHECK-NEXT:  entry:
+// CPP-CHECK-NEXT:    tail call void @llvm.aarch64.sme.zero.zt(i32 0)
+// CPP-CHECK-NEXT:    ret void
+//
+void test_svzero_zt(void) __arm_streaming_compatible __arm_shared_za __arm_preserves_za  {
----------------
sdesmalen-arm wrote:

```suggestion
void test_svzero_zt(void) __arm_streaming_compatible __arm_shared_za __arm_preserves_za  {
```
This should actually lead to a diagnostic (but I don't think we've implemented those yet), since svzero_zt doesn't preserve ZA.

https://github.com/llvm/llvm-project/pull/72274