[XRay] Implement powerpc64le xray.

Summary:
powerpc64 big-endian is not supported, but I believe that most logic can
be shared, except for xray_powerpc64.cc.

Also add a function InvalidateInstructionCache to xray_util.h, which is
copied from llvm/Support/Memory.cpp. I'm not sure if I need to add a unittest,
and I don't know how.

Reviewers: dberris, echristo, iteratee, kbarton, hfinkel

Subscribers: mehdi_amini, nemanjai, mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D29742

llvm-svn: 294781

1 files changed, 15 insertions, 0 deletions

diff --git a/compiler-rt/lib/xray/xray_trampoline_powerpc64.cc b/compiler-rt/lib/xray/xray_trampoline_powerpc64.cc
new file mode 100644
index 00000000000..878c46930fe
--- /dev/null
+++ b/compiler-rt/lib/xray/xray_trampoline_powerpc64.cc
@@ -0,0 +1,15 @@
+#include <atomic>
+#include <xray/xray_interface.h>
+
+namespace __xray {
+
+extern std::atomic<void (*)(int32_t, XRayEntryType)> XRayPatchedFunction;
+
+// Implement this in C++ instead of assembly, to avoid dealing with ToC by hand.
+void CallXRayPatchedFunction(int32_t FuncId, XRayEntryType Type) {
+  auto fptr = __xray::XRayPatchedFunction.load();
+  if (fptr != nullptr)
+    (*fptr)(FuncId, Type);
+}
+
+} // namespace __xray