Files
snmalloc/src/pal/pal_apple.h
David Chisnall e371edf11e Attempt at an Apple PAL.
Totally untested, but now we have macOS CI we can test there...
2019-02-25 12:54:16 +00:00

89 lines
1.9 KiB
C++

#pragma once
#ifdef __APPLE__
# include "../ds/bits.h"
# include "../mem/allocconfig.h"
# include <pthread.h>
# include <stdio.h>
# include <strings.h>
# include <sys/mman.h>
namespace snmalloc
{
/**
* PAL implementation for Apple systems (macOS, iOS, watchOS, tvOS...).
*/
class PALApple
{
public:
/**
* Bitmap of PalFeatures flags indicating the optional features that this
* PAL supports.
*/
static constexpr uint64_t pal_features = 0;
static void error(const char* const str)
{
puts(str);
abort();
}
/// Notify platform that we will not be using these pages
void notify_not_using(void* p, size_t size) noexcept
{
assert(bits::is_aligned_block<OS_PAGE_SIZE>(p, size));
madvise(p, size, MADV_FREE);
}
/// Notify platform that we will be using these pages
template<ZeroMem zero_mem>
void notify_using(void* p, size_t size) noexcept
{
assert(
bits::is_aligned_block<OS_PAGE_SIZE>(p, size) || (zero_mem == NoZero));
if constexpr (zero_mem == YesZero)
zero(p, size);
}
/// OS specific function for zeroing memory
template<bool page_aligned = false>
void zero(void* p, size_t size) noexcept
{
if (page_aligned || bits::is_aligned_block<OS_PAGE_SIZE>(p, size))
{
assert(bits::is_aligned_block<OS_PAGE_SIZE>(p, size));
void* r = mmap(
p,
size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
-1,
0);
if (r != MAP_FAILED)
return;
}
bzero(p, size);
}
template<bool committed>
void* reserve(size_t* size) noexcept
{
void* p = mmap(
NULL,
*size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
-1,
0);
if (p == MAP_FAILED)
error("Out of memory");
return p;
}
};
}
#endif