[clang] __sys builtin support (PR #145079)

[Eli Friedman via cfe-commits]

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@@ -0,0 +1,68 @@
+// REQUIRES: aarch64-registered-target
+
+// RUN: %clang_cc1 -triple arm64-windows -fms-compatibility -S \
+// RUN: -o - %s | FileCheck %s -check-prefix CHECK-ASM
+
+// RUN: %clang_cc1 -triple arm64-darwin -fms-compatibility -S \
+// RUN: -o - %s | FileCheck %s -check-prefix CHECK-ASM
+
+// RUN: %clang_cc1 -triple arm64-windows -fms-compatibility -emit-llvm \
+// RUN: -o - %s | FileCheck %s -check-prefix CHECK-IR
+
+// RUN: %clang_cc1 -triple arm64-darwin -fms-compatibility -emit-llvm \
+// RUN: -o - %s | FileCheck %s -check-prefix CHECK-IR
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efriedma-quic wrote:

I don't think we need all four of these runs... maybe we can shave off a couple?

https://github.com/llvm/llvm-project/pull/145079