Mesen-SX/Core/CallstackManager.cpp

#include "stdafx.h"
#include "CallstackManager.h"
#include "Debugger.h"
#include "DebugBreakHelper.h"
#include "Profiler.h"

CallstackManager::CallstackManager(Debugger* debugger)
{
	_debugger = debugger;
	_profiler.reset(new Profiler(debugger));
}

CallstackManager::~CallstackManager()
{
}

void CallstackManager::Push(AddressInfo& src, uint32_t srcAddr, AddressInfo& dest, uint32_t destAddr, AddressInfo& ret,
                            uint32_t returnAddress, StackFrameFlags flags)
{
	if (_callstack.size() >= 511)
	{
		//Ensure callstack stays below 512 entries - games can use various tricks that could keep making the callstack grow
		_callstack.pop_front();
	}

	StackFrameInfo stackFrame;
	stackFrame.Source = srcAddr;
	stackFrame.Target = destAddr;

	stackFrame.Return = returnAddress;
	stackFrame.AbsReturn = ret;

	stackFrame.Flags = flags;

	_callstack.push_back(stackFrame);
	_profiler->StackFunction(dest, flags);
}

void CallstackManager::Pop(AddressInfo& dest, uint32_t destAddress)
{
	if (_callstack.empty())
	{
		return;
	}

	StackFrameInfo prevFrame = _callstack.back();
	_callstack.pop_back();
	_profiler->UnstackFunction();

	uint32_t returnAddr = prevFrame.Return;

	if (!_callstack.empty() && destAddress != returnAddr)
	{
		//Mismatch, pop that stack frame and add the new one
		bool foundMatch = false;
		for (int i = (int)_callstack.size() - 1; i >= 0; i--)
		{
			if (destAddress == _callstack[i].Return)
			{
				//Found a matching stack frame, unstack until that point
				foundMatch = true;
				for (int j = (int)_callstack.size() - i - 1; j >= 0; j--)
				{
					_callstack.pop_back();
					_profiler->UnstackFunction();
				}
				break;
			}
		}

		if (!foundMatch)
		{
			//Couldn't find a matching frame, replace the current one
			Push(prevFrame.AbsReturn, returnAddr, dest, destAddress, prevFrame.AbsReturn, returnAddr,
			     StackFrameFlags::None);
		}
	}
}

void CallstackManager::GetCallstack(StackFrameInfo* callstackArray, uint32_t& callstackSize)
{
	DebugBreakHelper helper(_debugger);
	int i = 0;
	for (StackFrameInfo& info : _callstack)
	{
		callstackArray[i] = info;
		i++;
	}
	callstackSize = i;
}

int32_t CallstackManager::GetReturnAddress()
{
	DebugBreakHelper helper(_debugger);
	if (_callstack.empty())
	{
		return -1;
	}
	return _callstack.back().Return;
}

Profiler* CallstackManager::GetProfiler()
{
	return _profiler.get();
}