OSX implementation of rtl_AllocateAligned
This was SVN commit r6206.
This commit is contained in:
parent
23ade72800
commit
3be2bfa7ac
@ -1,5 +1,12 @@
|
||||
#include "precompiled.h"
|
||||
|
||||
#include "lib/sysdep/rtl.h"
|
||||
#include "lib/bits.h"
|
||||
|
||||
// Linux has posix_memalign, AFAIK our other gcc platforms do not have it.
|
||||
#define HAVE_POSIX_MEMALIGN OS_LINUX
|
||||
|
||||
#if HAVE_POSIX_MEMALIGN
|
||||
|
||||
void* rtl_AllocateAligned(size_t size, size_t alignment)
|
||||
{
|
||||
@ -16,3 +23,39 @@ void rtl_FreeAligned(void* alignedPointer)
|
||||
{
|
||||
free(alignedPointer);
|
||||
}
|
||||
|
||||
#else // Fallback aligned allocation using malloc
|
||||
|
||||
void* rtl_AllocateAligned(size_t size, size_t align)
|
||||
{
|
||||
// This ensures we have enough extra space to store the original pointer,
|
||||
// and produce an aligned buffer, assuming the platform malloc ensures at
|
||||
// least sizeof(void*) alignment.
|
||||
if (align < 2*sizeof(void*))
|
||||
align = 2*sizeof(void*);
|
||||
|
||||
void* const malloc_ptr = malloc(size + align);
|
||||
if (!malloc_ptr)
|
||||
return NULL;
|
||||
|
||||
// Round malloc_ptr up to the next aligned address, leaving some unused
|
||||
// space before the pointer we'll return. The minimum alignment above
|
||||
// ensures we'll have at least sizeof(void*) extra space.
|
||||
void* const aligned_ptr =
|
||||
(void *)(round_down(uintptr_t(malloc_ptr), uintptr_t(align)) + align);
|
||||
|
||||
// Just make sure we did the right thing with all the alignment hacks above.
|
||||
debug_assert(((void**)aligned_ptr) - 1 >= malloc_ptr);
|
||||
|
||||
// Store the original pointer which will have to be sent to free().
|
||||
((void **)aligned_ptr)[-1] = malloc_ptr;
|
||||
|
||||
return aligned_ptr;
|
||||
}
|
||||
|
||||
void rtl_FreeAligned(void* alignedPointer)
|
||||
{
|
||||
free(((void**)alignedPointer)[-1]);
|
||||
}
|
||||
|
||||
#endif
|
Loading…
Reference in New Issue
Block a user