1 files changed, 58 insertions, 32 deletions

diff --git a/openjdkjvmti/ti_stack.cc b/openjdkjvmti/ti_stack.cc
index 4a3eac8a15..5de4a81f5e 100644
--- a/openjdkjvmti/ti_stack.cc
+++ b/openjdkjvmti/ti_stack.cc
@@ -673,24 +673,34 @@ jvmtiError StackUtil::GetThreadListStackTraces(jvmtiEnv* env,
   return ERR(NONE);
 }
 
+// Walks up the stack counting Java frames. This is not StackVisitor::ComputeNumFrames, as
+// runtime methods and transitions must not be counted.
+struct GetFrameCountVisitor : public art::StackVisitor {
+  explicit GetFrameCountVisitor(art::Thread* thread)
+      : art::StackVisitor(thread, nullptr, art::StackVisitor::StackWalkKind::kIncludeInlinedFrames),
+        count(0) {}
+
+  bool VisitFrame() override REQUIRES_SHARED(art::Locks::mutator_lock_) {
+    art::ArtMethod* m = GetMethod();
+    const bool do_count = !(m == nullptr || m->IsRuntimeMethod());
+    if (do_count) {
+      count++;
+    }
+    return true;
+  }
+
+  size_t count;
+};
+
 struct GetFrameCountClosure : public art::Closure {
  public:
   GetFrameCountClosure() : count(0) {}
 
   void Run(art::Thread* self) override REQUIRES_SHARED(art::Locks::mutator_lock_) {
-    // This is not StackVisitor::ComputeNumFrames, as runtime methods and transitions must not be
-    // counted.
-    art::StackVisitor::WalkStack(
-        [&](const art::StackVisitor* stack_visitor) REQUIRES_SHARED(art::Locks::mutator_lock_) {
-          art::ArtMethod* m = stack_visitor->GetMethod();
-          if (m != nullptr && !m->IsRuntimeMethod()) {
-            count++;
-          }
-          return true;
-        },
-        self,
-        /* context= */ nullptr,
-        art::StackVisitor::StackWalkKind::kIncludeInlinedFrames);
+    GetFrameCountVisitor visitor(self);
+    visitor.WalkStack(false);
+
+    count = visitor.count;
   }
 
   size_t count;
@@ -733,30 +743,46 @@ jvmtiError StackUtil::GetFrameCount(jvmtiEnv* env ATTRIBUTE_UNUSED,
   return ERR(NONE);
 }
 
+// Walks up the stack 'n' callers, when used with Thread::WalkStack.
+struct GetLocationVisitor : public art::StackVisitor {
+  GetLocationVisitor(art::Thread* thread, size_t n_in)
+      : art::StackVisitor(thread, nullptr, art::StackVisitor::StackWalkKind::kIncludeInlinedFrames),
+        n(n_in),
+        count(0),
+        caller(nullptr),
+        caller_dex_pc(0) {}
+
+  bool VisitFrame() override REQUIRES_SHARED(art::Locks::mutator_lock_) {
+    art::ArtMethod* m = GetMethod();
+    const bool do_count = !(m == nullptr || m->IsRuntimeMethod());
+    if (do_count) {
+      DCHECK(caller == nullptr);
+      if (count == n) {
+        caller = m;
+        caller_dex_pc = GetDexPc(false);
+        return false;
+      }
+      count++;
+    }
+    return true;
+  }
+
+  const size_t n;
+  size_t count;
+  art::ArtMethod* caller;
+  uint32_t caller_dex_pc;
+};
+
 struct GetLocationClosure : public art::Closure {
  public:
   explicit GetLocationClosure(size_t n_in) : n(n_in), method(nullptr), dex_pc(0) {}
 
   void Run(art::Thread* self) override REQUIRES_SHARED(art::Locks::mutator_lock_) {
-    // Walks up the stack 'n' callers.
-    size_t count = 0u;
-    art::StackVisitor::WalkStack(
-        [&](const art::StackVisitor* stack_visitor) REQUIRES_SHARED(art::Locks::mutator_lock_) {
-          art::ArtMethod* m = stack_visitor->GetMethod();
-          if (m != nullptr && !m->IsRuntimeMethod()) {
-            DCHECK(method == nullptr);
-            if (count == n) {
-              method = m;
-              dex_pc = stack_visitor->GetDexPc(/*abort_on_failure=*/false);
-              return false;
-            }
-            count++;
-          }
-          return true;
-        },
-        self,
-        /* context= */ nullptr,
-        art::StackVisitor::StackWalkKind::kIncludeInlinedFrames);
+    GetLocationVisitor visitor(self, n);
+    visitor.WalkStack(false);
+
+    method = visitor.caller;
+    dex_pc = visitor.caller_dex_pc;
   }
 
   const size_t n;