Files
melonDS/src/ARMJIT_Global.cpp
2024-11-18 21:31:56 +01:00

127 lines
2.9 KiB
C++

#include "ARMJIT_Global.h"
#include "ARMJIT_Memory.h"
#ifdef _WIN32
#include <windows.h>
#else
#include <sys/mman.h>
#include <unistd.h>
#endif
#include <stdio.h>
#include <stdint.h>
#include <mutex>
namespace melonDS
{
namespace ARMJIT_Global
{
std::mutex globalMutex;
#if defined(__APPLE__) && defined(__aarch64__)
#define APPLE_AARCH64
#endif
#ifndef APPLE_AARCH64
static constexpr size_t NumCodeMemSlices = 4;
static constexpr size_t CodeMemoryAlignedSize = NumCodeMemSlices * CodeMemorySliceSize;
// I haven't heard of pages larger than 16 KB
u8 CodeMemory[CodeMemoryAlignedSize + 16*1024];
u32 AvailableCodeMemSlices = (1 << NumCodeMemSlices) - 1;
u8* GetAlignedCodeMemoryStart()
{
return reinterpret_cast<u8*>((reinterpret_cast<intptr_t>(CodeMemory) + (16*1024-1)) & ~static_cast<intptr_t>(16*1024-1));
}
#endif
int RefCounter = 0;
void* AllocateCodeMem()
{
std::lock_guard guard(globalMutex);
#ifndef APPLE_AARCH64
if (AvailableCodeMemSlices)
{
int slice = __builtin_ctz(AvailableCodeMemSlices);
AvailableCodeMemSlices &= ~(1 << slice);
//printf("allocating slice %d\n", slice);
return &GetAlignedCodeMemoryStart()[slice * CodeMemorySliceSize];
}
#endif
// allocate
#ifdef _WIN32
return VirtualAlloc(nullptr, CodeMemorySliceSize, MEM_RESERVE|MEM_COMMIT, PAGE_EXECUTE_READWRITE);
#elif defined(APPLE_AARCH64)
return mmap(NULL, CodeMemorySliceSize, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS | MAP_JIT,-1, 0);
#else
//printf("mmaping...\n");
return mmap(nullptr, CodeMemorySliceSize, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
#endif
}
void FreeCodeMem(void* codeMem)
{
std::lock_guard guard(globalMutex);
#ifndef APPLE_AARCH64
for (int i = 0; i < NumCodeMemSlices; i++)
{
if (codeMem == &GetAlignedCodeMemoryStart()[CodeMemorySliceSize * i])
{
//printf("freeing slice\n");
AvailableCodeMemSlices |= 1 << i;
return;
}
}
#endif
#ifdef _WIN32
VirtualFree(codeMem, CodeMemorySliceSize, MEM_RELEASE|MEM_DECOMMIT);
#else
munmap(codeMem, CodeMemorySliceSize);
#endif
}
void Init()
{
std::lock_guard guard(globalMutex);
RefCounter++;
if (RefCounter == 1)
{
#ifdef _WIN32
DWORD dummy;
VirtualProtect(GetAlignedCodeMemoryStart(), CodeMemoryAlignedSize, PAGE_EXECUTE_READWRITE, &dummy);
#elif defined(APPLE_AARCH64)
// Apple aarch64 always uses dynamic allocation
#else
mprotect(GetAlignedCodeMemoryStart(), CodeMemoryAlignedSize, PROT_EXEC | PROT_READ | PROT_WRITE);
#endif
ARMJIT_Memory::RegisterFaultHandler();
}
}
void DeInit()
{
std::lock_guard guard(globalMutex);
RefCounter--;
if (RefCounter == 0)
{
ARMJIT_Memory::UnregisterFaultHandler();
}
}
}
}