Combine JDWP location events
The runtime now sends location events BREAKPOINT, SINGLE_STEP, METHOD_ENTRY,
METHOD_EXIT and METHOD_EXIT_WITH_RETURN_VALUE in the same JDWP event packet
when they relate to the same location.
We update the Dbg::UpdateDebugger method to take initial event flags and
returned value. It allows to call this method from DebugInstrumentationListener
so we can treat method entry/exit events with breakpoint and single-step.
In the interpreter, we ensure we do not call Instrumentation::DexPcMovedEvent
when Instrumentation::MethodEnterEvent has just been called or when we're about
to call Instrumentation::MethodExitEvent. This prevents from sending duplicated
events.
I measured the average performance impact on some benchmarks with a Nexus 4
without a debugger attached:
* 1%-2% for the computed-goto-based interpreter (default interpreter)
* 5%-10% for the switch-based interpreter.
This is mostly due to the test of the boolean flag for the method entry event.
Bug: https://code.google.com/p/android/issues/detail?id=68427
Bug: 11874828
Change-Id: Ic4ff61375ff6b4ed5825adeac09f61f97b4be619
diff --git a/runtime/interpreter/interpreter_switch_impl.cc b/runtime/interpreter/interpreter_switch_impl.cc
index 9c13973..97c216d 100644
--- a/runtime/interpreter/interpreter_switch_impl.cc
+++ b/runtime/interpreter/interpreter_switch_impl.cc
@@ -48,11 +48,20 @@
} while (false)
// Code to run before each dex instruction.
-#define PREAMBLE()
+#define PREAMBLE() \
+ do { \
+ DCHECK(!inst->IsReturn()); \
+ if (UNLIKELY(notified_method_entry_event)) { \
+ notified_method_entry_event = false; \
+ } else if (UNLIKELY(instrumentation->HasDexPcListeners())) { \
+ instrumentation->DexPcMovedEvent(self, shadow_frame.GetThisObject(code_item->ins_size_), \
+ shadow_frame.GetMethod(), dex_pc); \
+ } \
+ } while (false)
template<bool do_access_check, bool transaction_active>
JValue ExecuteSwitchImpl(Thread* self, MethodHelper& mh, const DexFile::CodeItem* code_item,
- ShadowFrame& shadow_frame, JValue result_register) {
+ ShadowFrame& shadow_frame, JValue result_register) {
bool do_assignability_check = do_access_check;
if (UNLIKELY(!shadow_frame.HasReferenceArray())) {
LOG(FATAL) << "Invalid shadow frame for interpreter use";
@@ -61,11 +70,13 @@
self->VerifyStack();
uint32_t dex_pc = shadow_frame.GetDexPC();
+ bool notified_method_entry_event = false;
const instrumentation::Instrumentation* const instrumentation = Runtime::Current()->GetInstrumentation();
if (LIKELY(dex_pc == 0)) { // We are entering the method as opposed to deoptimizing..
if (UNLIKELY(instrumentation->HasMethodEntryListeners())) {
instrumentation->MethodEnterEvent(self, shadow_frame.GetThisObject(code_item->ins_size_),
shadow_frame.GetMethod(), 0);
+ notified_method_entry_event = true;
}
}
const uint16_t* const insns = code_item->insns_;
@@ -74,10 +85,6 @@
while (true) {
dex_pc = inst->GetDexPc(insns);
shadow_frame.SetDexPC(dex_pc);
- if (UNLIKELY(instrumentation->HasDexPcListeners())) {
- instrumentation->DexPcMovedEvent(self, shadow_frame.GetThisObject(code_item->ins_size_),
- shadow_frame.GetMethod(), dex_pc);
- }
TraceExecution(shadow_frame, inst, dex_pc, mh);
inst_data = inst->Fetch16(0);
switch (inst->Opcode(inst_data)) {
@@ -163,7 +170,6 @@
break;
}
case Instruction::RETURN_VOID: {
- PREAMBLE();
JValue result;
if (do_access_check) {
// If access checks are required then the dex-to-dex compiler and analysis of
@@ -182,7 +188,6 @@
return result;
}
case Instruction::RETURN_VOID_BARRIER: {
- PREAMBLE();
QuasiAtomic::MembarStoreLoad();
JValue result;
if (UNLIKELY(self->TestAllFlags())) {
@@ -196,7 +201,6 @@
return result;
}
case Instruction::RETURN: {
- PREAMBLE();
JValue result;
result.SetJ(0);
result.SetI(shadow_frame.GetVReg(inst->VRegA_11x(inst_data)));
@@ -211,7 +215,6 @@
return result;
}
case Instruction::RETURN_WIDE: {
- PREAMBLE();
JValue result;
result.SetJ(shadow_frame.GetVRegLong(inst->VRegA_11x(inst_data)));
if (UNLIKELY(self->TestAllFlags())) {
@@ -225,7 +228,6 @@
return result;
}
case Instruction::RETURN_OBJECT: {
- PREAMBLE();
JValue result;
if (UNLIKELY(self->TestAllFlags())) {
CheckSuspend(self);