[clang] [SYCL] Add sycl_external attribute (PR #140282)

[via cfe-commits]

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@@ -0,0 +1,52 @@
+// RUN: %clang_cc1 -fsycl-is-device -fsyntax-only -verify -DSYCL %s
+// RUN: %clang_cc1 -fsycl-is-host -fsyntax-only -verify -DHOST %s
+// RUN: %clang_cc1 -verify %s
+
+// Semantic tests for sycl_external attribute
+
+#ifdef SYCL
+
+__attribute__((sycl_external(3))) // expected-error {{'sycl_external' attribute takes no arguments}}
+void bar() {}
+
+__attribute__((sycl_external)) // expected-error {{'sycl_external' attribute cannot be applied to a function without external linkage}}
+static void func1() {}
+
+namespace {
+  __attribute__((sycl_external)) // expected-error {{'sycl_external' attribute cannot be applied to a function without external linkage}}
+  void func2() {}
+
+  struct UnnX {};
+}
+
+__attribute__((sycl_external)) // expected-error {{'sycl_external' attribute cannot be applied to a function without external linkage}}
+  void func4(UnnX) {}
+
+class A {
+  __attribute__((sycl_external))
+  A() {}
+
+  __attribute__((sycl_external)) void func3() {}
+};
+
+class B {
+public:
+  __attribute__((sycl_external)) virtual void foo() {}
+
+  __attribute__((sycl_external)) virtual void bar() = 0;
+};
+
+__attribute__((sycl_external)) int *func0() { return nullptr; }
+
+__attribute__((sycl_external)) void func2(int *) {}
+
+#elif defined(HOST)
+
+// expected-no-diagnostics
+__attribute__((sycl_external)) void func3() {}
+
+#else
+__attribute__((sycl_external)) // expected-warning {{'sycl_external' attribute ignored}}
+void baz() {}
+
+#endif
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schittir wrote:

Thank you. I split concerns and followed your suggestions.

https://github.com/llvm/llvm-project/pull/140282