1 files changed, 65 insertions, 0 deletions
diff --git a/include/xray/xray_interface.h b/include/xray/xray_interface.h
new file mode 100644
index 0000000000000..9e712b1fa2a86
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+++ b/include/xray/xray_interface.h
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+//===-- xray_interface.h ----------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of XRay, a dynamic runtime instrumentation system.
+//
+// APIs for controlling XRay functionality explicitly.
+//===----------------------------------------------------------------------===//
+#ifndef XRAY_XRAY_INTERFACE_H
+#define XRAY_XRAY_INTERFACE_H
+
+#include <cstdint>
+
+extern "C" {
+
+enum XRayEntryType { ENTRY = 0, EXIT = 1, TAIL = 2 };
+
+// Provide a function to invoke for when instrumentation points are hit. This is
+// a user-visible control surface that overrides the default implementation. The
+// function provided should take the following arguments:
+//
+//   - function id: an identifier that indicates the id of a function; this id
+//                  is generated by xray; the mapping between the function id
+//                  and the actual function pointer is available through
+//                  __xray_table.
+//   - entry type: identifies what kind of instrumentation point was encountered
+//                 (function entry, function exit, etc.). See the enum
+//                 XRayEntryType for more details.
+//
+// The user handler must handle correctly spurious calls after this handler is
+// removed or replaced with another handler, because it would be too costly for
+// XRay runtime to avoid spurious calls.
+// To prevent circular calling, the handler function itself and all its
+// direct&indirect callees must not be instrumented with XRay, which can be
+// achieved by marking them all with: __attribute__((xray_never_instrument))
+//
+// Returns 1 on success, 0 on error.
+extern int __xray_set_handler(void (*entry)(int32_t, XRayEntryType));
+
+// This removes whatever the currently provided handler is. Returns 1 on
+// success, 0 on error.
+extern int __xray_remove_handler();
+
+enum XRayPatchingStatus {
+  NOT_INITIALIZED = 0,
+  SUCCESS = 1,
+  ONGOING = 2,
+  FAILED = 3,
+};
+
+// This tells XRay to patch the instrumentation points. See XRayPatchingStatus
+// for possible result values.
+extern XRayPatchingStatus __xray_patch();
+
+// Reverses the effect of __xray_patch(). See XRayPatchingStatus for possible
+// result values.
+extern XRayPatchingStatus __xray_unpatch();
+}
+
+#endif