heap: replace exchange_free with deallocate

The `std::rt::heap` API is Rust's global allocator, so there's no need
to have this as a separate API.

src/libstd/rc.rs

@@ -33,7 +33,7 @@ use option::{Option, Some, None};
 use ptr;
 use ptr::RawPtr;
 use mem::{min_align_of, size_of};
-use rt::heap::exchange_free;
+use rt::heap::deallocate;
 
 struct RcBox<T> {
     value: T,
@@ -105,8 +105,8 @@ impl<T> Drop for Rc<T> {
                     self.dec_weak();
 
                     if self.weak() == 0 {
-                        exchange_free(self.ptr as *mut u8, size_of::<RcBox<T>>(),
-                                      min_align_of::<RcBox<T>>())
+                        deallocate(self.ptr as *mut u8, size_of::<RcBox<T>>(),
+                                   min_align_of::<RcBox<T>>())
                     }
                 }
             }
@@ -179,8 +179,8 @@ impl<T> Drop for Weak<T> {
                 // the weak count starts at 1, and will only go to
                 // zero if all the strong pointers have disappeared.
                 if self.weak() == 0 {
-                    exchange_free(self.ptr as *mut u8, size_of::<RcBox<T>>(),
-                                  min_align_of::<RcBox<T>>())
+                    deallocate(self.ptr as *mut u8, size_of::<RcBox<T>>(),
+                               min_align_of::<RcBox<T>>())
                 }
             }
         }

src/libstd/rt/heap.rs

@@ -165,13 +165,8 @@ pub unsafe fn exchange_malloc(size: uint, align: uint) -> *mut u8 {
 #[lang="exchange_free"]
 #[inline]
 // FIXME: #13994 (rustc should pass align and size here)
-pub unsafe fn exchange_free_(ptr: *mut u8) {
-    exchange_free(ptr, 0, 8)
-}
-
-#[inline]
-pub unsafe fn exchange_free(ptr: *mut u8, size: uint, align: uint) {
-    deallocate(ptr, size, align);
+unsafe fn exchange_free(ptr: *mut u8) {
+    deallocate(ptr, 0, 8);
 }
 
 // FIXME: #7496
@@ -212,7 +207,7 @@ pub unsafe extern "C" fn rust_malloc(size: uint, align: uint) -> *mut u8 {
 #[deprecated]
 #[cfg(not(test))]
 pub unsafe extern "C" fn rust_free(ptr: *mut u8, size: uint, align: uint) {
-    exchange_free(ptr, size, align)
+    deallocate(ptr, size, align)
 }
 
 #[cfg(test)]

src/libstd/slice.rs

@@ -109,7 +109,7 @@ use ops::Drop;
 use option::{None, Option, Some};
 use ptr::RawPtr;
 use ptr;
-use rt::heap::{exchange_malloc, exchange_free};
+use rt::heap::{exchange_malloc, deallocate};
 use unstable::finally::try_finally;
 use vec::Vec;
 
@@ -330,7 +330,7 @@ impl<'a, T: Clone> CloneableVector<T> for &'a [T] {
                         ptr::read(&*p.offset(j));
                     }
                     // FIXME: #13994 (should pass align and size here)
-                    exchange_free(ret as *mut u8, 0, 8);
+                    deallocate(ret as *mut u8, 0, 8);
                 });
             mem::transmute(ret)
         }
@@ -377,7 +377,7 @@ impl<'a, T: Clone> CloneableVector<T> for &'a [T] {
                         ptr::read(&*p.offset(j));
                     }
                     // FIXME: #13994 (should pass align and size here)
-                    exchange_free(ret as *mut u8, 0, 8);
+                    deallocate(ret as *mut u8, 0, 8);
                 });
             mem::transmute(ret)
         }
@@ -817,7 +817,7 @@ impl<T> Drop for MoveItems<T> {
         for _x in *self {}
         unsafe {
             // FIXME: #13994 (should pass align and size here)
-            exchange_free(self.allocation, 0, 8)
+            deallocate(self.allocation, 0, 8)
         }
     }
 }

src/libsync/arc.rs

@@ -15,7 +15,7 @@
 
 use std::mem;
 use std::ptr;
-use std::rt::heap::exchange_free;
+use std::rt::heap::deallocate;
 use std::sync::atomics;
 use std::mem::{min_align_of, size_of};
 
@@ -191,8 +191,8 @@ impl<T: Share + Send> Drop for Arc<T> {
 
         if self.inner().weak.fetch_sub(1, atomics::Release) == 1 {
             atomics::fence(atomics::Acquire);
-            unsafe { exchange_free(self.x as *mut u8, size_of::<ArcInner<T>>(),
-                                   min_align_of::<ArcInner<T>>()) }
+            unsafe { deallocate(self.x as *mut u8, size_of::<ArcInner<T>>(),
+                                min_align_of::<ArcInner<T>>()) }
         }
     }
 }
@@ -242,8 +242,8 @@ impl<T: Share + Send> Drop for Weak<T> {
         // the memory orderings
         if self.inner().weak.fetch_sub(1, atomics::Release) == 1 {
             atomics::fence(atomics::Acquire);
-            unsafe { exchange_free(self.x as *mut u8, size_of::<ArcInner<T>>(),
-                                   min_align_of::<ArcInner<T>>()) }
+            unsafe { deallocate(self.x as *mut u8, size_of::<ArcInner<T>>(),
+                                min_align_of::<ArcInner<T>>()) }
         }
     }
 }