110 lines
2.8 KiB
C++
110 lines
2.8 KiB
C++
// Copyright 2014 Dolphin Emulator Project
|
|
// Licensed under GPLv2+
|
|
// Refer to the license.txt file included.
|
|
|
|
#pragma once
|
|
|
|
#include "Common/Common.h"
|
|
#include "Common/MemoryUtil.h"
|
|
|
|
// Everything that needs to generate code should inherit from this.
|
|
// You get memory management for free, plus, you can use all emitter functions without
|
|
// having to prefix them with gen-> or something similar.
|
|
// Example implementation:
|
|
// class JIT : public CodeBlock<ARMXEmitter> {}
|
|
template<class T> class CodeBlock : public T, NonCopyable
|
|
{
|
|
private:
|
|
// A privately used function to set the executable RAM space to something invalid.
|
|
// For debugging usefulness it should be used to set the RAM to a host specific breakpoint instruction
|
|
virtual void PoisonMemory() = 0;
|
|
|
|
protected:
|
|
u8 *region;
|
|
size_t region_size;
|
|
size_t parent_region_size;
|
|
|
|
bool m_has_child;
|
|
bool m_is_child;
|
|
CodeBlock* m_child;
|
|
|
|
public:
|
|
CodeBlock()
|
|
: region(nullptr), region_size(0), parent_region_size(0),
|
|
m_has_child(false), m_is_child(false), m_child(nullptr)
|
|
{
|
|
}
|
|
|
|
virtual ~CodeBlock() { if (region) FreeCodeSpace(); }
|
|
|
|
// Call this before you generate any code.
|
|
void AllocCodeSpace(int size, bool need_low = true)
|
|
{
|
|
region_size = size;
|
|
region = (u8*)AllocateExecutableMemory(region_size, need_low);
|
|
T::SetCodePtr(region);
|
|
}
|
|
|
|
// Always clear code space with breakpoints, so that if someone accidentally executes
|
|
// uninitialized, it just breaks into the debugger.
|
|
void ClearCodeSpace()
|
|
{
|
|
PoisonMemory();
|
|
ResetCodePtr();
|
|
}
|
|
|
|
// Call this when shutting down. Don't rely on the destructor, even though it'll do the job.
|
|
void FreeCodeSpace()
|
|
{
|
|
FreeMemoryPages(region, region_size);
|
|
region = nullptr;
|
|
region_size = 0;
|
|
parent_region_size = 0;
|
|
if (m_has_child)
|
|
{
|
|
m_child->region = nullptr;
|
|
m_child->region_size = 0;
|
|
}
|
|
}
|
|
|
|
bool IsInSpace(u8 *ptr) const
|
|
{
|
|
return (ptr >= region) && (ptr < (region + region_size));
|
|
}
|
|
|
|
// Cannot currently be undone. Will write protect the entire code region.
|
|
// Start over if you need to change the code (call FreeCodeSpace(), AllocCodeSpace()).
|
|
void WriteProtect()
|
|
{
|
|
WriteProtectMemory(region, region_size, true);
|
|
}
|
|
|
|
void ResetCodePtr()
|
|
{
|
|
T::SetCodePtr(region);
|
|
}
|
|
|
|
size_t GetSpaceLeft() const
|
|
{
|
|
return (m_has_child ? parent_region_size : region_size) - (T::GetCodePtr() - region);
|
|
}
|
|
|
|
bool IsAlmostFull() const
|
|
{
|
|
// This should be bigger than the biggest block ever.
|
|
return GetSpaceLeft() < 0x10000;
|
|
}
|
|
void AddChildCodeSpace(CodeBlock* child, size_t size)
|
|
{
|
|
_assert_msg_(DYNA_REC, !m_has_child, "Already have a child! Can't have another!");
|
|
m_child = child;
|
|
m_has_child = true;
|
|
m_child->m_is_child = true;
|
|
u8* child_region = region + region_size - size;
|
|
m_child->region = child_region;
|
|
m_child->region_size = size;
|
|
m_child->ResetCodePtr();
|
|
parent_region_size = region_size - size;
|
|
}
|
|
};
|