// option. This file may not be copied, modified, or distributed
// except according to those terms.
#![no_std]
-#![feature(allocator_api, rustc_private)]
-#![cfg_attr(any(unix, target_os = "redox"), feature(libc))]
-
-// The minimum alignment guaranteed by the architecture. This value is used to
-// add fast paths for low alignment values.
-#[cfg(all(any(target_arch = "x86",
- target_arch = "arm",
- target_arch = "mips",
- target_arch = "powerpc",
- target_arch = "powerpc64")))]
-const MIN_ALIGN: usize = 8;
-#[cfg(all(any(target_arch = "x86_64",
- target_arch = "aarch64",
- target_arch = "mips64",
- target_arch = "s390x",
- target_arch = "sparc64")))]
-const MIN_ALIGN: usize = 16;
pub struct System;
+
#[cfg(any(windows, unix, target_os = "redox"))]
mod realloc_fallback {
use core::alloc::{GlobalAlloc, Layout};
use core::cmp;
use core::ptr;
impl super::System {
- pub(crate) unsafe fn realloc_fallback(&self, ptr: *mut u8, old_layout: Layout,
- new_size: usize) -> *mut u8 {
+ pub(crate) unsafe fn realloc_fallback(
+ &self,
+ ptr: *mut u8,
+ old_layout: Layout,
+ new_size: usize,
+ ) -> *mut u8 {
// Docs for GlobalAlloc::realloc require this to be valid:
let new_layout = Layout::from_size_align_unchecked(new_size, old_layout.align());
let new_ptr = GlobalAlloc::alloc(self, new_layout);
}
#[cfg(any(unix, target_os = "redox"))]
mod platform {
- extern crate libc;
+ use core::alloc::{GlobalAlloc, Layout};
+ use core::ffi::c_void;
use core::ptr;
- use MIN_ALIGN;
use System;
- use core::alloc::{GlobalAlloc, Layout};
+ extern "C" {
+ fn posix_memalign(memptr: *mut *mut c_void, align: usize, size: usize) -> i32;
+ fn free(p: *mut c_void);
+ }
unsafe impl GlobalAlloc for System {
#[inline]
unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
- 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)
- }
+ aligned_malloc(&layout)
}
#[inline]
unsafe fn alloc_zeroed(&self, layout: Layout) -> *mut u8 {
- if layout.align() <= MIN_ALIGN && layout.align() <= layout.size() {
- libc::calloc(layout.size(), 1) as *mut u8
- } else {
- let ptr = self.alloc(layout.clone());
- if !ptr.is_null() {
- ptr::write_bytes(ptr, 0, layout.size());
- }
- ptr
+ let ptr = self.alloc(layout.clone());
+ 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)
+ free(ptr as *mut 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 {
- self.realloc_fallback(ptr, layout, new_size)
- }
+ self.realloc_fallback(ptr, layout, new_size)
}
}
- #[cfg(any(target_os = "android",
- target_os = "hermit",
- 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 = "hermit",
- target_os = "redox",
- target_os = "solaris")))]
- #[inline]
unsafe fn aligned_malloc(layout: &Layout) -> *mut u8 {
let mut out = ptr::null_mut();
- let ret = libc::posix_memalign(&mut out, layout.align(), layout.size());
- if ret != 0 {
- ptr::null_mut()
- } else {
- out as *mut u8
- }
+ let ret = posix_memalign(&mut out, layout.align(), layout.size());
+ if ret != 0 { ptr::null_mut() } else { out as *mut u8 }
}
}
#[cfg(windows)]
#[allow(nonstandard_style)]
mod platform {
- use MIN_ALIGN;
- use System;
use core::alloc::{GlobalAlloc, Layout};
+ use System;
type LPVOID = *mut u8;
type HANDLE = LPVOID;
type SIZE_T = usize;
}
#[inline]
unsafe fn allocate_with_flags(layout: Layout, flags: DWORD) -> *mut u8 {
- let ptr = if layout.align() <= MIN_ALIGN {
- HeapAlloc(GetProcessHeap(), flags, layout.size())
- } else {
- let size = layout.size() + layout.align();
- let ptr = HeapAlloc(GetProcessHeap(), flags, size);
- if ptr.is_null() {
- ptr
- } else {
- align_ptr(ptr, layout.align())
- }
- };
- ptr as *mut u8
+ let size = layout.size() + layout.align();
+ let ptr = HeapAlloc(GetProcessHeap(), flags, size);
+ (if ptr.is_null() { ptr } else { align_ptr(ptr, layout.align()) }) as *mut u8
}
unsafe impl GlobalAlloc for System {
#[inline]
}
#[inline]
unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
- if layout.align() <= MIN_ALIGN {
- let err = HeapFree(GetProcessHeap(), 0, ptr as LPVOID);
- debug_assert!(err != 0, "Failed to free heap memory: {}",
- GetLastError());
- } else {
- let header = get_header(ptr);
- let err = HeapFree(GetProcessHeap(), 0, header.0 as LPVOID);
- debug_assert!(err != 0, "Failed to free heap memory: {}",
- GetLastError());
- }
+ let header = get_header(ptr);
+ let err = HeapFree(GetProcessHeap(), 0, header.0 as LPVOID);
+ debug_assert!(err != 0, "Failed to free heap memory: {}", GetLastError());
}
#[inline]
unsafe fn realloc(&self, ptr: *mut u8, layout: Layout, new_size: usize) -> *mut u8 {
- if layout.align() <= MIN_ALIGN {
- HeapReAlloc(GetProcessHeap(), 0, ptr as LPVOID, new_size) as *mut u8
- } else {
- self.realloc_fallback(ptr, layout, new_size)
- }
+ self.realloc_fallback(ptr, layout, new_size)
}
}
}
projects / rust.git / blobdiff