[clang] [Clang][HTO] Add clang attribute for propagating llvm-level information (PR #83059)

[William Moses via cfe-commits]

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@@ -0,0 +1,14 @@
+// RUN: %clang_cc1 -debug-info-kind=limited -emit-llvm -o - | FileCheck %s
+
+void t1() __attribute__((llvm_fn_attr("custom_attr", "custom_value"), llvm_fn_attr("second_attr", "second_value")));
+
+void t1()
+{
+}
+
+void t2();
+
+void t3() {
+	t2() ____attribute__((llvm_fn_attr("custom_attr", "custom_value"), llvm_fn_attr("second_attr", "second_value")));
+}
+
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wsmoses wrote:

@jdoerfert okay tests added and appear working, ready for review

https://github.com/llvm/llvm-project/pull/83059