Move to components/hashglobe

components/hashglobe/src/alloc.rs

@@ -0,0 +1,152 @@
+// FORK NOTE: Copied from liballoc_system, removed unnecessary APIs,
+// APIs take size/align directly instead of Layout
+
+
+
+
+// The minimum alignment guaranteed by the architecture. This value is used to
+// add fast paths for low alignment values. In practice, the alignment is a
+// constant at the call site and the branch will be optimized out.
+#[cfg(all(any(target_arch = "x86",
+              target_arch = "arm",
+              target_arch = "mips",
+              target_arch = "powerpc",
+              target_arch = "powerpc64",
+              target_arch = "asmjs",
+              target_arch = "wasm32")))]
+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 use self::platform::{alloc, dealloc};
+
+#[cfg(any(unix, target_os = "redox"))]
+mod platform {
+    extern crate libc;
+
+    use std::ptr;
+
+    use super::MIN_ALIGN;
+
+    #[inline]
+    pub unsafe fn alloc(size: usize, align: usize) -> *mut u8 {
+        let ptr = if align <= MIN_ALIGN {
+            libc::malloc(size) as *mut u8
+        } else {
+            aligned_malloc(size, align)
+        };
+        ptr
+    }
+
+    #[inline]
+    pub unsafe fn dealloc(ptr: *mut u8, _align: usize) {
+        libc::free(ptr as *mut libc::c_void)
+    }
+
+    #[cfg(any(target_os = "android", target_os = "redox"))]
+    #[inline]
+    unsafe fn aligned_malloc(size: usize, align: usize) -> *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(align, size) as *mut u8
+    }
+
+    #[cfg(not(any(target_os = "android", target_os = "redox")))]
+    #[inline]
+    unsafe fn aligned_malloc(size: usize, align: usize) -> *mut u8 {
+        let mut out = ptr::null_mut();
+        let ret = libc::posix_memalign(&mut out, align, size);
+        if ret != 0 {
+            ptr::null_mut()
+        } else {
+            out as *mut u8
+        }
+    }
+}
+
+#[cfg(windows)]
+#[allow(bad_style)]
+mod platform {
+
+    use super::MIN_ALIGN;
+    type LPVOID = *mut u8;
+    type HANDLE = LPVOID;
+    type SIZE_T = usize;
+    type DWORD = u32;
+    type BOOL = i32;
+
+
+    extern "system" {
+        fn GetProcessHeap() -> HANDLE;
+        fn HeapAlloc(hHeap: HANDLE, dwFlags: DWORD, dwBytes: SIZE_T) -> LPVOID;
+        fn HeapFree(hHeap: HANDLE, dwFlags: DWORD, lpMem: LPVOID) -> BOOL;
+        fn GetLastError() -> DWORD;
+    }
+
+    #[repr(C)]
+    struct Header(*mut u8);
+
+    unsafe fn get_header<'a>(ptr: *mut u8) -> &'a mut Header {
+        &mut *(ptr as *mut Header).offset(-1)
+    }
+
+    unsafe fn align_ptr(ptr: *mut u8, align: usize) -> *mut u8 {
+        let aligned = ptr.offset((align - (ptr as usize & (align - 1))) as isize);
+        *get_header(aligned) = Header(ptr);
+        aligned
+    }
+
+    #[inline]
+    unsafe fn allocate_with_flags(size: usize, align: usize, flags: DWORD) -> *mut u8
+    {
+        if align <= MIN_ALIGN {
+            HeapAlloc(GetProcessHeap(), flags, size)
+        } else {
+            let size = size + align;
+            let ptr = HeapAlloc(GetProcessHeap(), flags, size);
+            if ptr.is_null() {
+                ptr
+            } else {
+                align_ptr(ptr, align)
+            }
+        }
+    }
+
+    #[inline]
+    pub unsafe fn alloc(size: usize, align: usize) -> *mut u8 {
+        allocate_with_flags(size, align, 0)
+    }
+
+    #[inline]
+    pub unsafe fn dealloc(ptr: *mut u8, align: usize) {
+        if 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());
+        }
+    }
+}

components/hashglobe/src/fake.rs

@@ -0,0 +1,149 @@
+//! This module contains shims around the stdlib HashMap
+//! that add fallible methods
+//!
+//! These methods are a lie. They are not actually fallible. This is just to make
+//! it smooth to switch between hashmap impls in a codebase.
+
+use std::hash::{BuildHasher, Hash};
+use std::collections::HashMap as StdMap;
+use std::collections::HashSet as StdSet;
+use std::ops::{Deref, DerefMut};
+
+pub use std::collections::hash_map::{Entry, RandomState};
+
+pub struct HashMap<K, V, S = RandomState>(StdMap<K, V, S>);
+
+
+use FailedAllocationError;
+
+impl<K, V, S> Deref for HashMap<K, V, S> {
+    type Target = StdMap<K, V, S>;
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    } 
+}
+
+impl<K, V, S> DerefMut for HashMap<K, V, S> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    } 
+}
+
+impl<K: Hash + Eq, V> HashMap<K, V, RandomState> {
+
+    #[inline]
+    pub fn new() -> HashMap<K, V, RandomState> {
+        HashMap(StdMap::new())
+    }
+
+    #[inline]
+    pub fn with_capacity(capacity: usize) -> HashMap<K, V, RandomState> {
+        HashMap(StdMap::with_capacity(capacity))
+    }
+
+    #[inline]
+    pub fn try_with_capacity(capacity: usize) -> Result<HashMap<K, V, RandomState>, FailedAllocationError> {
+        Ok(HashMap(StdMap::with_capacity(capacity)))
+    }
+}
+
+
+impl<K, V, S> HashMap<K, V, S>
+    where K: Eq + Hash,
+          S: BuildHasher
+{
+    #[inline]
+    pub fn try_with_hasher(hash_builder: S) -> Result<HashMap<K, V, S>, FailedAllocationError> {
+        Ok(HashMap(StdMap::with_hasher(hash_builder)))
+    }
+
+    #[inline]
+    pub fn try_with_capacity_and_hasher(capacity: usize, hash_builder: S) -> Result<HashMap<K, V, S>, FailedAllocationError> {
+        Ok(HashMap(StdMap::with_capacity_and_hasher(capacity, hash_builder)))
+    }
+
+    pub fn with_capacity_and_hasher(capacity: usize, hash_builder: S) -> HashMap<K, V, S> {
+        HashMap(StdMap::with_capacity_and_hasher(capacity, hash_builder))
+    }
+
+
+    #[inline]
+    pub fn try_reserve(&mut self, additional: usize) -> Result<(), FailedAllocationError> {
+        Ok(self.reserve(additional))
+    }
+
+    pub fn try_shrink_to_fit(&mut self) -> Result<(), FailedAllocationError> {
+        Ok(self.shrink_to_fit())
+    }
+
+    pub fn try_entry(&mut self, key: K) -> Result<Entry<K, V>, FailedAllocationError> {
+        Ok(self.entry(key))
+    }
+
+    #[inline]
+    pub fn try_insert(&mut self, k: K, v: V) -> Result<Option<V>, FailedAllocationError> {
+        Ok(self.insert(k, v))
+    }
+}
+
+pub struct HashSet<T, S = RandomState>(StdSet<T, S>);
+
+
+impl<T, S> Deref for HashSet<T, S> {
+    type Target = StdSet<T, S>;
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    } 
+}
+
+impl<T, S> DerefMut for HashSet<T, S> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    } 
+}
+
+impl<T: Hash + Eq> HashSet<T, RandomState> {
+
+    #[inline]
+    pub fn new() -> HashSet<T, RandomState> {
+        HashSet(StdSet::new())
+    }
+
+    #[inline]
+    pub fn with_capacity(capacity: usize) -> HashSet<T, RandomState> {
+        HashSet(StdSet::with_capacity(capacity))
+    }
+}
+
+
+impl<T, S> HashSet<T, S>
+    where T: Eq + Hash,
+          S: BuildHasher
+{
+
+    #[inline]
+    pub fn with_hasher(hasher: S) -> HashSet<T, S> {
+        HashSet(StdSet::with_hasher(hasher))
+    }
+
+
+    #[inline]
+    pub fn with_capacity_and_hasher(capacity: usize, hasher: S) -> HashSet<T, S> {
+        HashSet(StdSet::with_capacity_and_hasher(capacity, hasher))
+    }
+
+    #[inline]
+    pub fn try_reserve(&mut self, additional: usize) -> Result<(), FailedAllocationError> {
+        Ok(self.reserve(additional))
+    }
+
+    #[inline]
+    pub fn try_shrink_to_fit(&mut self) -> Result<(), FailedAllocationError> {
+        Ok(self.shrink_to_fit())
+    }
+
+    #[inline]
+    pub fn try_insert(&mut self, value: T) -> Result<bool, FailedAllocationError> {
+        Ok(self.insert(value))
+    }
+}

components/hashglobe/src/lib.rs

@@ -0,0 +1,36 @@
+pub use std::*;
+
+mod table;
+mod shim;
+mod alloc;
+pub mod hash_map;
+pub mod hash_set;
+
+pub mod fake;
+
+use std::{error, fmt};
+
+trait Recover<Q: ?Sized> {
+    type Key;
+
+    fn get(&self, key: &Q) -> Option<&Self::Key>;
+    fn take(&mut self, key: &Q) -> Option<Self::Key>;
+    fn replace(&mut self, key: Self::Key) -> Option<Self::Key>;
+}
+
+#[derive(Debug)]
+pub struct FailedAllocationError {
+    reason: &'static str,
+}
+
+impl error::Error for FailedAllocationError {
+    fn description(&self) -> &str {
+        self.reason
+    }
+}
+
+impl fmt::Display for FailedAllocationError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.reason.fmt(f)
+    }
+}

components/hashglobe/src/shim.rs

@@ -0,0 +1,60 @@
+use std::marker::PhantomData;
+
+pub struct NonZeroPtr<T: 'static>(&'static T);
+
+impl<T: 'static> NonZeroPtr<T> {
+    pub unsafe fn new_unchecked(ptr: *mut T) -> Self {
+        NonZeroPtr(&*ptr)
+    }
+    pub fn as_ptr(&self) -> *mut T {
+        self.0 as *const T as *mut T
+    }
+}
+
+pub struct Unique<T: 'static> {
+    ptr: NonZeroPtr<T>,
+    _marker: PhantomData<T>,
+}
+
+impl<T: 'static> Unique<T> {
+    pub unsafe fn new_unchecked(ptr: *mut T) -> Self {
+        Unique {
+            ptr: NonZeroPtr::new_unchecked(ptr),
+            _marker: PhantomData,
+        }
+    }
+    pub fn as_ptr(&self) -> *mut T {
+        self.ptr.as_ptr()
+    }
+}
+
+unsafe impl<T: Send + 'static> Send for Unique<T> { }
+
+unsafe impl<T: Sync + 'static> Sync for Unique<T> { }
+
+pub struct Shared<T: 'static>  {
+    ptr: NonZeroPtr<T>,
+    _marker: PhantomData<T>,
+    // force it to be !Send/!Sync
+    _marker2: PhantomData<*const u8>,
+}
+
+impl<T: 'static> Shared<T> {
+    pub unsafe fn new_unchecked(ptr: *mut T) -> Self {
+        Shared {
+            ptr: NonZeroPtr::new_unchecked(ptr),
+            _marker: PhantomData,
+            _marker2: PhantomData,
+        }
+    }
+
+    pub unsafe fn as_mut(&self) -> &mut T {
+        &mut *self.ptr.as_ptr()
+    }
+}
+
+impl<'a, T> From<&'a mut T> for Shared<T> {
+    fn from(reference: &'a mut T) -> Self {
+        unsafe { Shared::new_unchecked(reference) }
+    }
+}