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Diffstat (limited to 'src/libstd/sys/unix/alloc.rs')
| -rw-r--r-- | src/libstd/sys/unix/alloc.rs | 97 |
1 files changed, 0 insertions, 97 deletions
diff --git a/src/libstd/sys/unix/alloc.rs b/src/libstd/sys/unix/alloc.rs deleted file mode 100644 index 8e193935460..00000000000 --- a/src/libstd/sys/unix/alloc.rs +++ /dev/null @@ -1,97 +0,0 @@ -use crate::alloc::{GlobalAlloc, Layout, System}; -use crate::ptr; -use crate::sys_common::alloc::{realloc_fallback, MIN_ALIGN}; - -#[stable(feature = "alloc_system_type", since = "1.28.0")] -unsafe impl GlobalAlloc for System { - #[inline] - unsafe fn alloc(&self, layout: Layout) -> *mut u8 { - // jemalloc provides alignment less than MIN_ALIGN for small allocations. - // So only rely on MIN_ALIGN if size >= align. - // Also see <https://github.com/rust-lang/rust/issues/45955> and - // <https://github.com/rust-lang/rust/issues/62251#issuecomment-507580914>. - if layout.align() <= MIN_ALIGN && layout.align() <= layout.size() { - libc::malloc(layout.size()) as *mut u8 - } else { - #[cfg(target_os = "macos")] - { - if layout.align() > (1 << 31) { - return ptr::null_mut(); - } - } - aligned_malloc(&layout) - } - } - - #[inline] - unsafe fn alloc_zeroed(&self, layout: Layout) -> *mut u8 { - // See the comment above in `alloc` for why this check looks the way it does. - if layout.align() <= MIN_ALIGN && layout.align() <= layout.size() { - libc::calloc(layout.size(), 1) as *mut u8 - } else { - let ptr = self.alloc(layout); - if !ptr.is_null() { - ptr::write_bytes(ptr, 0, layout.size()); - } - ptr - } - } - - #[inline] - unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) { - libc::free(ptr as *mut libc::c_void) - } - - #[inline] - unsafe fn realloc(&self, ptr: *mut u8, layout: Layout, new_size: usize) -> *mut u8 { - if layout.align() <= MIN_ALIGN && layout.align() <= new_size { - libc::realloc(ptr as *mut libc::c_void, new_size) as *mut u8 - } else { - realloc_fallback(self, ptr, layout, new_size) - } - } -} - -#[cfg(any( - target_os = "android", - target_os = "illumos", - target_os = "redox", - target_os = "solaris" -))] -#[inline] -unsafe fn aligned_malloc(layout: &Layout) -> *mut u8 { - // On android we currently target API level 9 which unfortunately - // doesn't have the `posix_memalign` API used below. Instead we use - // `memalign`, but this unfortunately has the property on some systems - // where the memory returned cannot be deallocated by `free`! - // - // Upon closer inspection, however, this appears to work just fine with - // Android, so for this platform we should be fine to call `memalign` - // (which is present in API level 9). Some helpful references could - // possibly be chromium using memalign [1], attempts at documenting that - // memalign + free is ok [2] [3], or the current source of chromium - // which still uses memalign on android [4]. - // - // [1]: https://codereview.chromium.org/10796020/ - // [2]: https://code.google.com/p/android/issues/detail?id=35391 - // [3]: https://bugs.chromium.org/p/chromium/issues/detail?id=138579 - // [4]: https://chromium.googlesource.com/chromium/src/base/+/master/ - // /memory/aligned_memory.cc - libc::memalign(layout.align(), layout.size()) as *mut u8 -} - -#[cfg(not(any( - target_os = "android", - target_os = "illumos", - target_os = "redox", - target_os = "solaris" -)))] -#[inline] -unsafe fn aligned_malloc(layout: &Layout) -> *mut u8 { - let mut out = ptr::null_mut(); - // posix_memalign requires that the alignment be a multiple of `sizeof(void*)`. - // Since these are all powers of 2, we can just use max. - let align = layout.align().max(crate::mem::size_of::<usize>()); - let ret = libc::posix_memalign(&mut out, align, layout.size()); - if ret != 0 { ptr::null_mut() } else { out as *mut u8 } -} |