piwalker/dolphin
1
0
Fork 0
mirror of https://github.com/dolphin-emu/dolphin.git synced 2025-07-21 05:09:34 -06:00
Code Issues Packages Projects Releases Wiki Activity

Remove code for only allocating low memory

Browse Source 
This is unnecessary when we have position-independent code.
This commit is contained in:
JosJuice
2017-04-14 12:53:32 +02:00
parent 89535468eb
commit 4b4cf509f8
7 changed files with 26 additions and 84 deletions
Download Patch File Download Diff File Expand all files Collapse all files

59
Source/Core/Common/MemoryUtil.cpp
View File

@ -29,74 +29,25 @@
#endif
#endif
// Valgrind doesn't support MAP_32BIT.
// Uncomment the following line to be able to run Dolphin in Valgrind.
//#undef MAP_32BIT
namespace Common
{
#if !defined(_WIN32) && defined(_M_X86_64) && !defined(MAP_32BIT)
#include <unistd.h>
static uintptr_t RoundPage(uintptr_t addr)
{
uintptr_t mask = getpagesize() - 1;
return (addr + mask) & ~mask;
}
#endif
// This is purposely not a full wrapper for virtualalloc/mmap, but it
// provides exactly the primitive operations that Dolphin needs.
void* AllocateExecutableMemory(size_t size, bool low)
void* AllocateExecutableMemory(size_t size)
{
#if defined(_WIN32)
void* ptr = VirtualAlloc(0, size, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
#else
static char* map_hint = nullptr;
#if defined(_M_X86_64) && !defined(MAP_32BIT)
// This OS has no flag to enforce allocation below the 4 GB boundary,
// but if we hint that we want a low address it is very likely we will
// get one.
// An older version of this code used MAP_FIXED, but that has the side
// effect of discarding already mapped pages that happen to be in the
// requested virtual memory range (such as the emulated RAM, sometimes).
if (low && (!map_hint))
map_hint = (char*)RoundPage(512 * 1024 * 1024); /* 0.5 GB rounded up to the next page */
#endif
void* ptr = mmap(map_hint, size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_ANON | MAP_PRIVATE
#if defined(_M_X86_64) && defined(MAP_32BIT)
| (low ? MAP_32BIT : 0)
#endif
,
-1, 0);
#endif /* defined(_WIN32) */
void* ptr =
mmap(nullptr, size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_ANON | MAP_PRIVATE, -1, 0);
#ifdef _WIN32
if (ptr == nullptr)
{
#else
if (ptr == MAP_FAILED)
{
ptr = nullptr;
#endif
PanicAlert("Failed to allocate executable memory. If you are running Dolphin in Valgrind, try "
"'#undef MAP_32BIT'.");
}
#if !defined(_WIN32) && defined(_M_X86_64) && !defined(MAP_32BIT)
else
{
if (low)
{
map_hint += size;
map_hint = (char*)RoundPage((uintptr_t)map_hint); /* round up to the next page */
}
}
#endif
#if _M_X86_64
if ((u64)ptr >= 0x80000000 && low == true)
PanicAlert("Executable memory ended up above 2GB!");
#endif
if (ptr == nullptr)
PanicAlert("Failed to allocate executable memory");
return ptr;
}