[XRay][clang] Add flag to choose instrumentation bundles

Summary:
This change addresses http://llvm.org/PR36926 by allowing users to pick
which instrumentation bundles to use, when instrumenting with XRay. In
particular, the flag `-fxray-instrumentation-bundle=` has four valid
values:

- `all`: the default, emits all instrumentation kinds
- `none`: equivalent to -fnoxray-instrument
- `function`: emits the entry/exit instrumentation
- `custom`: emits the custom event instrumentation

These can be combined either as comma-separated values, or as
repeated flag values.

Reviewers: echristo, kpw, eizan, pelikan

Reviewed By: pelikan

Subscribers: mgorny, cfe-commits

Differential Revision: https://reviews.llvm.org/D44970

llvm-svn: 329985

1 files changed, 29 insertions, 0 deletions

diff --git a/clang/lib/Basic/XRayInstr.cpp b/clang/lib/Basic/XRayInstr.cpp
new file mode 100644
index 00000000000..42f9038890a
--- /dev/null
+++ b/clang/lib/Basic/XRayInstr.cpp
@@ -0,0 +1,29 @@
+//===--- XRayInstr.cpp ------------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This is part of XRay, a function call instrumentation system.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Basic/XRayInstr.h"
+#include "llvm/ADT/StringSwitch.h"
+
+namespace clang {
+
+XRayInstrMask parseXRayInstrValue(StringRef Value) {
+  XRayInstrMask ParsedKind = llvm::StringSwitch<XRayInstrMask>(Value)
+                                 .Case("all", XRayInstrKind::All)
+                                 .Case("custom", XRayInstrKind::Custom)
+                                 .Case("function", XRayInstrKind::Function)
+                                 .Case("none", XRayInstrKind::None)
+                                 .Default(XRayInstrKind::None);
+  return ParsedKind;
+}
+
+} // namespace clang