grabbed ppsspp's MemArena

This commit is contained in:
bunnei 2014-03-31 21:04:50 -04:00
parent 4fdeadb8e2
commit 07ea22de5c
2 changed files with 423 additions and 216 deletions

View File

@ -1,14 +1,27 @@
// Copyright 2013 Dolphin Emulator Project
// Licensed under GPLv2
// Refer to the license.txt file included.
// Copyright (C) 2003 Dolphin Project.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0 or later versions.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License 2.0 for more details.
// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/
// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/
#include <string>
#include "common.h"
#include "memory_util.h"
#include "mem_arena.h"
#ifdef _WIN32
#include <windows.h>
//#include "CommonWindows.h"
#else
#include <sys/stat.h>
#include <fcntl.h>
@ -20,55 +33,134 @@
#include <linux/ashmem.h>
#endif
#endif
#include <set>
#if defined(__APPLE__)
static const char* ram_temp_file = "/tmp/gc_mem.tmp";
#elif !defined(_WIN32) // non OSX unixes
static const char* ram_temp_file = "/dev/shm/gc_mem.tmp";
#ifdef IOS
void* globalbase = NULL;
#endif
#ifdef ANDROID
#define ASHMEM_DEVICE "/dev/ashmem"
int AshmemCreateFileMapping(const char *name, size_t size)
// Hopefully this ABI will never change...
#define ASHMEM_DEVICE "/dev/ashmem"
/*
* ashmem_create_region - creates a new ashmem region and returns the file
* descriptor, or <0 on error
*
* `name' is an optional label to give the region (visible in /proc/pid/maps)
* `size' is the size of the region, in page-aligned bytes
*/
int ashmem_create_region(const char *name, size_t size)
{
int fd, ret;
fd = open(ASHMEM_DEVICE, O_RDWR);
if (fd < 0)
return fd;
int fd, ret;
// We don't really care if we can't set the name, it is optional
ret = ioctl(fd, ASHMEM_SET_NAME, name);
fd = open(ASHMEM_DEVICE, O_RDWR);
if (fd < 0)
return fd;
ret = ioctl(fd, ASHMEM_SET_SIZE, size);
if (ret < 0)
{
close(fd);
NOTICE_LOG(MEMMAP, "Ashmem returned error: 0x%08x", ret);
return ret;
}
return fd;
if (name) {
char buf[ASHMEM_NAME_LEN];
strncpy(buf, name, sizeof(buf));
ret = ioctl(fd, ASHMEM_SET_NAME, buf);
if (ret < 0)
goto error;
}
ret = ioctl(fd, ASHMEM_SET_SIZE, size);
if (ret < 0)
goto error;
return fd;
error:
ERROR_LOG(MEMMAP, "NASTY ASHMEM ERROR: ret = %08x", ret);
close(fd);
return ret;
}
int ashmem_set_prot_region(int fd, int prot)
{
return ioctl(fd, ASHMEM_SET_PROT_MASK, prot);
}
int ashmem_pin_region(int fd, size_t offset, size_t len)
{
struct ashmem_pin pin = { offset, len };
return ioctl(fd, ASHMEM_PIN, &pin);
}
int ashmem_unpin_region(int fd, size_t offset, size_t len)
{
struct ashmem_pin pin = { offset, len };
return ioctl(fd, ASHMEM_UNPIN, &pin);
}
#endif // Android
#ifndef _WIN32
// do not make this "static"
#if defined(MAEMO) || defined(MEEGO_EDITION_HARMATTAN)
std::string ram_temp_file = "/home/user/gc_mem.tmp";
#else
std::string ram_temp_file = "/tmp/gc_mem.tmp";
#endif
#elif !defined(_XBOX)
SYSTEM_INFO sysInfo;
#endif
// Windows mappings need to be on 64K boundaries, due to Alpha legacy.
#ifdef _WIN32
size_t roundup(size_t x) {
#ifndef _XBOX
int gran = sysInfo.dwAllocationGranularity ? sysInfo.dwAllocationGranularity : 0x10000;
#else
int gran = 0x10000; // 64k in 360
#endif
return (x + gran - 1) & ~(gran - 1);
}
#else
size_t roundup(size_t x) {
return x;
}
#endif
void MemArena::GrabLowMemSpace(size_t size)
{
#ifdef _WIN32
hMemoryMapping = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, (DWORD)(size), NULL);
#ifndef _XBOX
hMemoryMapping = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, (DWORD)(size), NULL);
GetSystemInfo(&sysInfo);
#endif
#elif defined(ANDROID)
fd = AshmemCreateFileMapping("Dolphin-emu", size);
if (fd < 0)
{
NOTICE_LOG(MEMMAP, "Ashmem allocation failed");
return;
}
// Use ashmem so we don't have to allocate a file on disk!
fd = ashmem_create_region("PPSSPP_RAM", size);
// Note that it appears that ashmem is pinned by default, so no need to pin.
if (fd < 0)
{
ERROR_LOG(MEMMAP, "Failed to grab ashmem space of size: %08x errno: %d", (int)size, (int)(errno));
return;
}
#else
mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
fd = open(ram_temp_file, O_RDWR | O_CREAT, mode);
unlink(ram_temp_file);
if (ftruncate(fd, size) < 0)
ERROR_LOG(MEMMAP, "Failed to allocate low memory space");
return;
mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
fd = open(ram_temp_file.c_str(), O_RDWR | O_CREAT, mode);
if (fd < 0)
{
ERROR_LOG(MEMMAP, "Failed to grab memory space as a file: %s of size: %08x errno: %d", ram_temp_file.c_str(), (int)size, (int)(errno));
return;
}
// delete immediately, we keep the fd so it still lives
unlink(ram_temp_file.c_str());
if (ftruncate(fd, size) != 0)
{
ERROR_LOG(MEMMAP, "Failed to ftruncate %d to size %08x", (int)fd, (int)size);
}
return;
#endif
}
@ -76,10 +168,13 @@ void MemArena::GrabLowMemSpace(size_t size)
void MemArena::ReleaseSpace()
{
#ifdef _WIN32
CloseHandle(hMemoryMapping);
hMemoryMapping = 0;
CloseHandle(hMemoryMapping);
hMemoryMapping = 0;
#elif defined(__SYMBIAN32__)
memmap->Close();
delete memmap;
#else
close(fd);
close(fd);
#endif
}
@ -87,23 +182,32 @@ void MemArena::ReleaseSpace()
void *MemArena::CreateView(s64 offset, size_t size, void *base)
{
#ifdef _WIN32
return MapViewOfFileEx(hMemoryMapping, FILE_MAP_ALL_ACCESS, 0, (DWORD)((u64)offset), size, base);
#ifdef _XBOX
size = roundup(size);
// use 64kb pages
void * ptr = VirtualAlloc(NULL, size, MEM_COMMIT | MEM_LARGE_PAGES, PAGE_READWRITE);
return ptr;
#else
void *retval = mmap(
base, size,
PROT_READ | PROT_WRITE,
MAP_SHARED | ((base == nullptr) ? 0 : MAP_FIXED),
fd, offset);
size = roundup(size);
void *ptr = MapViewOfFileEx(hMemoryMapping, FILE_MAP_ALL_ACCESS, 0, (DWORD)((u64)offset), size, base);
return ptr;
#endif
#else
void *retval = mmap(base, size, PROT_READ | PROT_WRITE, MAP_SHARED |
// Do not sync memory to underlying file. Linux has this by default.
#ifdef BLACKBERRY
MAP_NOSYNCFILE |
#elif defined(__FreeBSD__)
MAP_NOSYNC |
#endif
((base == 0) ? 0 : MAP_FIXED), fd, offset);
if (retval == MAP_FAILED)
{
NOTICE_LOG(MEMMAP, "mmap on %s failed", ram_temp_file);
return nullptr;
}
else
{
return retval;
}
if (retval == MAP_FAILED)
{
NOTICE_LOG(MEMMAP, "mmap on %s (fd: %d) failed", ram_temp_file.c_str(), (int)fd);
return 0;
}
return retval;
#endif
}
@ -111,184 +215,263 @@ void *MemArena::CreateView(s64 offset, size_t size, void *base)
void MemArena::ReleaseView(void* view, size_t size)
{
#ifdef _WIN32
UnmapViewOfFile(view);
#ifndef _XBOX
UnmapViewOfFile(view);
#endif
#elif defined(__SYMBIAN32__)
memmap->Decommit(((int)view - (int)memmap->Base()) & 0x3FFFFFFF, size);
#else
munmap(view, size);
munmap(view, size);
#endif
}
#ifndef __SYMBIAN32__
u8* MemArena::Find4GBBase()
{
#ifdef _M_X64
#ifdef _WIN32
// 64 bit
u8* base = (u8*)VirtualAlloc(0, 0xE1000000, MEM_RESERVE, PAGE_READWRITE);
VirtualFree(base, 0, MEM_RELEASE);
return base;
// 64 bit
u8* base = (u8*)VirtualAlloc(0, 0xE1000000, MEM_RESERVE, PAGE_READWRITE);
VirtualFree(base, 0, MEM_RELEASE);
return base;
#else
// Very precarious - mmap cannot return an error when trying to map already used pages.
// This makes the Windows approach above unusable on Linux, so we will simply pray...
return reinterpret_cast<u8*>(0x2300000000ULL);
// Very precarious - mmap cannot return an error when trying to map already used pages.
// This makes the Windows approach above unusable on Linux, so we will simply pray...
return reinterpret_cast<u8*>(0x2300000000ULL);
#endif
#else
// 32 bit
#else // 32 bit
#ifdef _WIN32
// The highest thing in any 1GB section of memory space is the locked cache. We only need to fit it.
u8* base = (u8*)VirtualAlloc(0, 0x31000000, MEM_RESERVE, PAGE_READWRITE);
if (base) {
VirtualFree(base, 0, MEM_RELEASE);
}
return base;
u8* base = (u8*)VirtualAlloc(0, 0x10000000, MEM_RESERVE, PAGE_READWRITE);
if (base) {
VirtualFree(base, 0, MEM_RELEASE);
}
return base;
#else
#ifdef ANDROID
// Android 4.3 changed how mmap works.
// if we map it private and then munmap it, we can't use the base returned.
// This may be due to changes in them support a full SELinux implementation.
const int flags = MAP_ANON;
#ifdef IOS
void* base = NULL;
if (globalbase == NULL){
base = mmap(0, 0x08000000, PROT_READ | PROT_WRITE,
MAP_ANON | MAP_SHARED, -1, 0);
if (base == MAP_FAILED) {
PanicAlert("Failed to map 128 MB of memory space: %s", strerror(errno));
return 0;
}
munmap(base, 0x08000000);
globalbase = base;
}
else{ base = globalbase; }
#else
const int flags = MAP_ANON | MAP_PRIVATE;
void* base = mmap(0, 0x10000000, PROT_READ | PROT_WRITE,
MAP_ANON | MAP_SHARED, -1, 0);
if (base == MAP_FAILED) {
PanicAlert("Failed to map 256 MB of memory space: %s", strerror(errno));
return 0;
}
munmap(base, 0x10000000);
#endif
const u32 MemSize = 0x31000000;
void* base = mmap(0, MemSize, PROT_NONE, flags, -1, 0);
if (base == MAP_FAILED) {
PanicAlert("Failed to map 1 GB of memory space: %s", strerror(errno));
return 0;
}
munmap(base, MemSize);
return static_cast<u8*>(base);
return static_cast<u8*>(base);
#endif
#endif
}
#endif
// yeah, this could also be done in like two bitwise ops...
#define SKIP(a_flags, b_flags)
// if (!(a_flags & MV_WII_ONLY) && (b_flags & MV_WII_ONLY))
// continue;
// if (!(a_flags & MV_FAKE_VMEM) && (b_flags & MV_FAKE_VMEM))
// continue;
static bool Memory_TryBase(u8 *base, const MemoryView *views, int num_views, u32 flags, MemArena *arena) {
// OK, we know where to find free space. Now grab it!
// We just mimic the popular BAT setup.
u32 position = 0;
u32 last_position = 0;
// OK, we know where to find free space. Now grab it!
// We just mimic the popular BAT setup.
size_t position = 0;
size_t last_position = 0;
// Zero all the pointers to be sure.
for (int i = 0; i < num_views; i++)
{
if (views[i].out_ptr_low)
*views[i].out_ptr_low = 0;
if (views[i].out_ptr)
*views[i].out_ptr = 0;
}
int i;
for (i = 0; i < num_views; i++)
{
if (views[i].flags & MV_MIRROR_PREVIOUS) {
position = last_position;
} else {
*(views[i].out_ptr_low) = (u8*)arena->CreateView(position, views[i].size);
if (!*views[i].out_ptr_low)
goto bail;
}
#ifdef _M_X64
*views[i].out_ptr = (u8*)arena->CreateView(
position, views[i].size, base + views[i].virtual_address);
#else
if (views[i].flags & MV_MIRROR_PREVIOUS) {
// No need to create multiple identical views.
*views[i].out_ptr = *views[i - 1].out_ptr;
} else {
*views[i].out_ptr = (u8*)arena->CreateView(
position, views[i].size, base + (views[i].virtual_address & 0x3FFFFFFF));
if (!*views[i].out_ptr)
goto bail;
}
#if defined(_XBOX)
void *ptr;
#endif
last_position = position;
position += views[i].size;
}
return true;
// Zero all the pointers to be sure.
for (int i = 0; i < num_views; i++)
{
if (views[i].out_ptr_low)
*views[i].out_ptr_low = 0;
if (views[i].out_ptr)
*views[i].out_ptr = 0;
}
int i;
for (i = 0; i < num_views; i++)
{
const MemoryView &view = views[i];
if (view.size == 0)
continue;
SKIP(flags, view.flags);
if (view.flags & MV_MIRROR_PREVIOUS) {
position = last_position;
}
else {
#ifdef __SYMBIAN32__
*(view.out_ptr_low) = (u8*)((int)arena->memmap->Base() + view.virtual_address);
arena->memmap->Commit(view.virtual_address & 0x3FFFFFFF, view.size);
}
*(view.out_ptr) = (u8*)((int)arena->memmap->Base() + view.virtual_address & 0x3FFFFFFF);
#elif defined(_XBOX)
*(view.out_ptr_low) = (u8*)(base + view.virtual_address);
//arena->memmap->Commit(view.virtual_address & 0x3FFFFFFF, view.size);
ptr = VirtualAlloc(base + (view.virtual_address & 0x3FFFFFFF), view.size, MEM_COMMIT, PAGE_READWRITE);
}
*(view.out_ptr) = (u8*)base + (view.virtual_address & 0x3FFFFFFF);
#else
*(view.out_ptr_low) = (u8*)arena->CreateView(position, view.size);
if (!*view.out_ptr_low)
goto bail;
}
#ifdef _M_X64
*view.out_ptr = (u8*)arena->CreateView(
position, view.size, base + view.virtual_address);
#else
if (view.flags & MV_MIRROR_PREVIOUS) { // TODO: should check if the two & 0x3FFFFFFF are identical.
// No need to create multiple identical views.
*view.out_ptr = *views[i - 1].out_ptr;
}
else {
*view.out_ptr = (u8*)arena->CreateView(
position, view.size, base + (view.virtual_address & 0x3FFFFFFF));
if (!*view.out_ptr)
goto bail;
}
#endif
#endif
last_position = position;
position += roundup(view.size);
}
return true;
bail:
// Argh! ERROR! Free what we grabbed so far so we can try again.
MemoryMap_Shutdown(views, i+1, flags, arena);
return false;
// Argh! ERROR! Free what we grabbed so far so we can try again.
for (int j = 0; j <= i; j++)
{
if (views[i].size == 0)
continue;
SKIP(flags, views[i].flags);
if (views[j].out_ptr_low && *views[j].out_ptr_low)
{
arena->ReleaseView(*views[j].out_ptr_low, views[j].size);
*views[j].out_ptr_low = NULL;
}
if (*views[j].out_ptr)
{
#ifdef _M_X64
arena->ReleaseView(*views[j].out_ptr, views[j].size);
#else
if (!(views[j].flags & MV_MIRROR_PREVIOUS))
{
arena->ReleaseView(*views[j].out_ptr, views[j].size);
}
#endif
*views[j].out_ptr = NULL;
}
}
return false;
}
u8 *MemoryMap_Setup(const MemoryView *views, int num_views, u32 flags, MemArena *arena)
{
u32 total_mem = 0;
int base_attempts = 0;
size_t total_mem = 0;
int base_attempts = 0;
for (int i = 0; i < num_views; i++)
{
if ((views[i].flags & MV_MIRROR_PREVIOUS) == 0)
total_mem += views[i].size;
}
// Grab some pagefile backed memory out of the void ...
arena->GrabLowMemSpace(total_mem);
for (int i = 0; i < num_views; i++)
{
if (views[i].size == 0)
continue;
SKIP(flags, views[i].flags);
if ((views[i].flags & MV_MIRROR_PREVIOUS) == 0)
total_mem += roundup(views[i].size);
}
// Grab some pagefile backed memory out of the void ...
#ifndef __SYMBIAN32__
arena->GrabLowMemSpace(total_mem);
#endif
// Now, create views in high memory where there's plenty of space.
// Now, create views in high memory where there's plenty of space.
#ifdef _M_X64
u8 *base = MemArena::Find4GBBase();
// This really shouldn't fail - in 64-bit, there will always be enough
// address space.
if (!Memory_TryBase(base, views, num_views, flags, arena))
{
PanicAlert("MemoryMap_Setup: Failed finding a memory base.");
exit(0);
return 0;
}
#else
#ifdef _WIN32
// Try a whole range of possible bases. Return once we got a valid one.
u32 max_base_addr = 0x7FFF0000 - 0x31000000;
u8 *base = NULL;
u8 *base = MemArena::Find4GBBase();
// This really shouldn't fail - in 64-bit, there will always be enough
// address space.
if (!Memory_TryBase(base, views, num_views, flags, arena))
{
PanicAlert("MemoryMap_Setup: Failed finding a memory base.");
return 0;
}
#elif defined(_XBOX)
// Reserve 256MB
u8 *base = (u8*)VirtualAlloc(0, 0x10000000, MEM_RESERVE | MEM_LARGE_PAGES, PAGE_READWRITE);
if (!Memory_TryBase(base, views, num_views, flags, arena))
{
PanicAlert("MemoryMap_Setup: Failed finding a memory base.");
exit(0);
return 0;
}
#elif defined(_WIN32)
// Try a whole range of possible bases. Return once we got a valid one.
u32 max_base_addr = 0x7FFF0000 - 0x10000000;
u8 *base = NULL;
for (u32 base_addr = 0x40000; base_addr < max_base_addr; base_addr += 0x40000)
{
base_attempts++;
base = (u8 *)base_addr;
if (Memory_TryBase(base, views, num_views, flags, arena))
{
INFO_LOG(MEMMAP, "Found valid memory base at %p after %i tries.", base, base_attempts);
base_attempts = 0;
break;
}
}
for (u32 base_addr = 0x01000000; base_addr < max_base_addr; base_addr += 0x400000)
{
base_attempts++;
base = (u8 *)base_addr;
if (Memory_TryBase(base, views, num_views, flags, arena))
{
INFO_LOG(MEMMAP, "Found valid memory base at %p after %i tries.", base, base_attempts);
base_attempts = 0;
break;
}
}
#elif defined(__SYMBIAN32__)
arena->memmap = new RChunk();
arena->memmap->CreateDisconnectedLocal(0, 0, 0x10000000);
if (!Memory_TryBase(arena->memmap->Base(), views, num_views, flags, arena))
{
PanicAlert("MemoryMap_Setup: Failed finding a memory base.");
return 0;
}
u8* base = arena->memmap->Base();
#else
// Linux32 is fine with the x64 method, although limited to 32-bit with no automirrors.
u8 *base = MemArena::Find4GBBase();
if (!Memory_TryBase(base, views, num_views, flags, arena))
{
PanicAlert("MemoryMap_Setup: Failed finding a memory base.");
exit(0);
return 0;
}
// Linux32 is fine with the x64 method, although limited to 32-bit with no automirrors.
u8 *base = MemArena::Find4GBBase();
if (!Memory_TryBase(base, views, num_views, flags, arena))
{
ERROR_LOG(MEMMAP, "MemoryMap_Setup: Failed finding a memory base.");
PanicAlert("MemoryMap_Setup: Failed finding a memory base.");
return 0;
}
#endif
#endif
if (base_attempts)
PanicAlert("No possible memory base pointer found!");
return base;
if (base_attempts)
PanicAlert("No possible memory base pointer found!");
return base;
}
void MemoryMap_Shutdown(const MemoryView *views, int num_views, u32 flags, MemArena *arena)
{
std::set<void*> freeset;
for (int i = 0; i < num_views; i++)
{
const MemoryView* view = &views[i];
u8** outptrs[2] = {view->out_ptr_low, view->out_ptr};
for (int j = 0; j < 2; j++)
{
u8** outptr = outptrs[j];
if (outptr && *outptr && !freeset.count(*outptr))
{
arena->ReleaseView(*outptr, view->size);
freeset.insert(*outptr);
*outptr = NULL;
}
}
}
for (int i = 0; i < num_views; i++)
{
if (views[i].size == 0)
continue;
SKIP(flags, views[i].flags);
if (views[i].out_ptr_low && *views[i].out_ptr_low)
arena->ReleaseView(*views[i].out_ptr_low, views[i].size);
if (*views[i].out_ptr && (views[i].out_ptr_low && *views[i].out_ptr != *views[i].out_ptr_low))
arena->ReleaseView(*views[i].out_ptr, views[i].size);
*views[i].out_ptr = NULL;
if (views[i].out_ptr_low)
*views[i].out_ptr_low = NULL;
}
}

View File

@ -1,7 +1,19 @@
// Copyright 2013 Dolphin Emulator Project
// Licensed under GPLv2
// Refer to the license.txt file included.
// Copyright (C) 2003 Dolphin Project.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0 or later versions.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License 2.0 for more details.
// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/
// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/
#ifndef _MEMARENA_H_
#define _MEMARENA_H_
@ -10,43 +22,55 @@
#include <windows.h>
#endif
#ifdef __SYMBIAN32__
#include <e32std.h>
#endif
#include "common.h"
// This class lets you create a block of anonymous RAM, and then arbitrarily map views into it.
// Multiple views can mirror the same section of the block, which makes it very convenient for emulating
// Multiple views can mirror the same section of the block, which makes it very convient for emulating
// memory mirrors.
class MemArena
{
public:
void GrabLowMemSpace(size_t size);
void ReleaseSpace();
void *CreateView(s64 offset, size_t size, void *base = nullptr);
void ReleaseView(void *view, size_t size);
void GrabLowMemSpace(size_t size);
void ReleaseSpace();
void *CreateView(s64 offset, size_t size, void *base = 0);
void ReleaseView(void *view, size_t size);
// This only finds 1 GB in 32-bit
static u8 *Find4GBBase();
#ifdef __SYMBIAN32__
RChunk* memmap;
#else
// This only finds 1 GB in 32-bit
static u8 *Find4GBBase();
#endif
private:
#ifdef _WIN32
HANDLE hMemoryMapping;
HANDLE hMemoryMapping;
#else
int fd;
int fd;
#endif
};
enum {
MV_MIRROR_PREVIOUS = 1,
MV_IS_PRIMARY_RAM = 0x100,
MV_MIRROR_PREVIOUS = 1,
// MV_FAKE_VMEM = 2,
// MV_WII_ONLY = 4,
MV_IS_PRIMARY_RAM = 0x100,
MV_IS_EXTRA1_RAM = 0x200,
MV_IS_EXTRA2_RAM = 0x400,
};
struct MemoryView
{
u8 **out_ptr_low;
u8 **out_ptr;
u32 virtual_address;
u32 size;
u32 flags;
u8 **out_ptr_low;
u8 **out_ptr;
u32 virtual_address;
u32 size;
u32 flags;
};
// Uses a memory arena to set up an emulator-friendly memory map according to