* Added some debug output for stepping.

* Fixed incorrect "step over" handling after hitting the temporary breakpoint.
  Could cause stepping into functions.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@31673 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/apps/debugger/ThreadHandler.cpp

@@ -109,6 +109,7 @@ ThreadHandler::HandleBreakpointHit(BreakpointHitEvent* event)
 {
 	CpuState* cpuState = event->GetCpuState();
 	target_addr_t instructionPointer = cpuState->InstructionPointer();
+printf("ThreadHandler::HandleBreakpointHit(): ip: %llx\n", instructionPointer);
 
 	// check whether this is a temporary breakpoint we're waiting for
 	if (fBreakpointAddress != 0 && instructionPointer == fBreakpointAddress
@@ -225,6 +226,7 @@ ThreadHandler::HandleThreadAction(uint32 action)
 		case MSG_THREAD_STEP_OUT:
 			break;
 	}
+printf("ThreadHandler::HandleThreadAction(MSG_THREAD_STEP_*)\n");
 
 	// We want to step. We need a stack trace for that purpose. If we don't
 	// have one yet, get it. Start with the CPU state.
@@ -246,16 +248,13 @@ ThreadHandler::HandleThreadAction(uint32 action)
 	}
 
 	StackFrame* frame = stackTrace->FrameAt(0);
+printf("  ip: %#llx\n", frame->InstructionPointer());
 
 	// When the thread is in a syscall, do the same for all step kinds: Stop it
 	// when it return by means of a breakpoint.
 	if (frame->Type() == STACK_FRAME_TYPE_SYSCALL) {
 		// set a breakpoint at the CPU state's instruction pointer (points to
 		// the return address, unlike the stack frame's instruction pointer)
-// TODO: That's OK in principle, but needs additional work with recursive
-// functions. We need to store some information that allows us to determine
-// whether we've actually stepped out of the current frame when we have hit
-// the breakpoint.
 		status_t error = _InstallTemporaryBreakpoint(
 			frame->GetCpuState()->InstructionPointer());
 		if (error != B_OK) {
@@ -270,6 +269,10 @@ ThreadHandler::HandleThreadAction(uint32 action)
 
 	// For "step out" just set a temporary breakpoint on the return address.
 	if (action == MSG_THREAD_STEP_OUT) {
+// TODO: That's OK in principle, but needs additional work with recursive
+// functions. We need to store some information that allows us to determine
+// whether we've actually stepped out of the current frame when we have hit
+// the breakpoint.
 		status_t error = _InstallTemporaryBreakpoint(frame->ReturnAddress());
 		if (error != B_OK) {
 			_StepFallback();
@@ -288,6 +291,8 @@ ThreadHandler::HandleThreadAction(uint32 action)
 		_StepFallback();
 		return;
 	}
+printf("  statement: %#llx - %#llx\n", fStepStatement->CoveringAddressRange().Start(),
+fStepStatement->CoveringAddressRange().End());
 
 	if (action == MSG_THREAD_STEP_INTO) {
 		// step into
@@ -426,6 +431,7 @@ ThreadHandler::_StepFallback()
 bool
 ThreadHandler::_DoStepOver(CpuState* cpuState)
 {
+printf("ThreadHandler::_DoStepOver()\n");
 	// The basic strategy is to single-step out of the statement like for
 	// "step into", only we have to avoid stepping into subroutines. Hence we
 	// check whether the current instruction is a subroutine call. If not, we
@@ -433,14 +439,18 @@ ThreadHandler::_DoStepOver(CpuState* cpuState)
 	InstructionInfo info;
 	if (fDebuggerInterface->GetArchitecture()->GetInstructionInfo(
 			cpuState->InstructionPointer(), info) != B_OK) {
+printf("  failed to get instruction info\n");
 		return false;
 	}
 
 	if (info.Type() != INSTRUCTION_TYPE_SUBROUTINE_CALL) {
 		_SingleStepThread(cpuState->InstructionPointer());
+printf("  not a subroutine call\n");
 		return true;
 	}
 
+printf("  subroutine call -- installing breakpoint at address %#llx\n",
+info.Address() + info.Size());
 	if (_InstallTemporaryBreakpoint(info.Address() + info.Size()) != B_OK)
 		return false;
 
@@ -520,7 +530,8 @@ ThreadHandler::_HandleBreakpointHitStep(CpuState* cpuState)
 			// otherwise we're done.
 			if (fStepStatement->ContainsAddress(
 					cpuState->InstructionPointer())) {
-				_SingleStepThread(cpuState->InstructionPointer());
+				if (!_DoStepOver(cpuState))
+					_StepFallback();
 				return true;
 			}
 			return false;
@@ -538,6 +549,7 @@ ThreadHandler::_HandleBreakpointHitStep(CpuState* cpuState)
 bool
 ThreadHandler::_HandleSingleStepStep(CpuState* cpuState)
 {
+printf("ThreadHandler::_HandleSingleStepStep(): ip: %llx\n", cpuState->InstructionPointer());
 	switch (fStepMode) {
 		case STEP_INTO:
 		{