Link stack frames of JNI stubs to JNI callbacks.

base/debug/stack_trace.cc

Index: base/debug/stack_trace.cc
diff --git a/base/debug/stack_trace.cc b/base/debug/stack_trace.cc
index f3ffef360f0680a8a36cdabc4fa43c5ee1fc390c..1762c9b02210705dd280c655a4421c6e0dddb444 100644
--- a/base/debug/stack_trace.cc
+++ b/base/debug/stack_trace.cc
@@ -9,6 +9,7 @@
 #include <algorithm>
 #include <sstream>
 
+#include "base/logging.h"
 #include "base/macros.h"
 
 #if HAVE_TRACE_STACK_FRAME_POINTERS
@@ -176,6 +177,17 @@ uintptr_t ScanStackForNextFrame(uintptr_t fp, uintptr_t stack_end) {
   return 0;
 }
 
+// Links stack frame |fp| to |parent_fp|, so that during stack unwinding
+// TraceStackFramePointers() visits |parent_fp| after visiting |fp|.
+// Both frame pointers must come from __builtin_frame_address().
+// Returns previous stack frame |fp| was linked to.
+void* LinkStackFrames(void* fpp, void* parent_fp) {
+  uintptr_t fp = reinterpret_cast<uintptr_t>(fpp) - kStackFrameAdjustment;
+  void* prev_parent_fp = reinterpret_cast<void**>(fp)[0];
+  reinterpret_cast<void**>(fp)[0] = parent_fp;
+  return prev_parent_fp;
+}
+
 #endif  // HAVE_TRACE_STACK_FRAME_POINTERS
 
 }  // namespace
@@ -245,6 +257,16 @@ size_t TraceStackFramePointers(const void** out_trace,
   return depth;
 }
 
+ScopedStackFrameLinker::ScopedStackFrameLinker(void* fp, void* parent_fp)
+  : fp_(fp), parent_fp_(parent_fp)
+  , original_parent_fp_(LinkStackFrames(fp, parent_fp)) {}

[Nico, 2016/10/25 19:36:33]

please run `git cl format`

+
+ScopedStackFrameLinker::~ScopedStackFrameLinker() {
+  void* previous_parent_fp = LinkStackFrames(fp_, original_parent_fp_);
+  CHECK_EQ(parent_fp_, previous_parent_fp)
+    << "Stack frame's parent pointer has changed!";
+}
+
 #endif  // HAVE_TRACE_STACK_FRAME_POINTERS
 
 }  // namespace debug