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vec examples compiling

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pull/182/head
Clifton King 6 years ago
parent 3e6e1001dc
commit 84179ba915
6 changed files with 46 additions and 30 deletions
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17
src/vec-alloc.md
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@ -157,7 +157,7 @@ such we will guard against this case explicitly.
Ok with all the nonsense out of the way, let's actually allocate some memory: Ok with all the nonsense out of the way, let's actually allocate some memory:
```rust,ignore ```rust,ignore
use std::alloc::oom; use std::alloc::{alloc, realloc, Layout, rust_oom};
fn grow(&mut self) { fn grow(&mut self) {
// this is all pretty delicate, so let's say it's all unsafe // this is all pretty delicate, so let's say it's all unsafe
@ -167,7 +167,8 @@ fn grow(&mut self) {
let elem_size = mem::size_of::<T>(); let elem_size = mem::size_of::<T>();
let (new_cap, ptr) = if self.cap == 0 { let (new_cap, ptr) = if self.cap == 0 {
let ptr = heap::allocate(elem_size, align); let layout = Layout::from_size_align_unchecked(elem_size, align);
let ptr = alloc(layout);
(1, ptr) (1, ptr)
} else { } else {
// as an invariant, we can assume that `self.cap < isize::MAX`, // as an invariant, we can assume that `self.cap < isize::MAX`,
@ -186,17 +187,17 @@ fn grow(&mut self) {
"capacity overflow"); "capacity overflow");
let new_num_bytes = old_num_bytes * 2; let new_num_bytes = old_num_bytes * 2;
let ptr = heap::reallocate(self.ptr.as_ptr() as *mut _, let layout = Layout::from_size_align_unchecked(old_num_bytes, align);
old_num_bytes, let ptr = realloc(self.ptr.as_ptr() as *mut _, layout, num_new_bytes);
new_num_bytes,
align);
(new_cap, ptr) (new_cap, ptr)
}; };
// If allocate or reallocate fail, we'll get `null` back // If allocate or reallocate fail, we'll get `null` back
if ptr.is_null() { oom(); } if ptr.is_null() {
rust_oom(Layout::from_size_align_unchecked(new_cap * elem_size, align));
}
self.ptr = Unique::new(ptr as *mut _); self.ptr = Unique::new(ptr as *mut _).unwrap();
self.cap = new_cap; self.cap = new_cap;
} }
} }

5
src/vec-dealloc.md
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@ -12,6 +12,8 @@ haven't actually allocated any memory.
```rust,ignore ```rust,ignore
use std::alloc::dealloc;
impl<T> Drop for Vec<T> { impl<T> Drop for Vec<T> {
fn drop(&mut self) { fn drop(&mut self) {
if self.cap != 0 { if self.cap != 0 {
@ -21,7 +23,8 @@ impl<T> Drop for Vec<T> {
let elem_size = mem::size_of::<T>(); let elem_size = mem::size_of::<T>();
let num_bytes = elem_size * self.cap; let num_bytes = elem_size * self.cap;
unsafe { unsafe {
heap::deallocate(self.ptr.as_ptr() as *mut _, num_bytes, align); let layout = Layout::from_size_align_unchecked(num_bytes, align);
dealloc(self.ptr.as_ptr() as *mut _, layout);
} }
} }
} }

10
src/vec-insert-remove.md
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@ -22,11 +22,11 @@ pub fn insert(&mut self, index: usize, elem: T) {
unsafe { unsafe {
if index < self.len { if index < self.len {
// ptr::copy(src, dest, len): "copy from source to dest len elems" // ptr::copy(src, dest, len): "copy from source to dest len elems"
ptr::copy(self.ptr.offset(index as isize), ptr::copy(self.ptr.as_ptr().offset(index as isize),
self.ptr.offset(index as isize + 1), self.ptr.as_ptr().offset(index as isize + 1),
self.len - index); self.len - index);
} }
ptr::write(self.ptr.offset(index as isize), elem); ptr::write(self.ptr.as_ptr().offset(index as isize), elem);
self.len += 1; self.len += 1;
} }
} }
@ -42,8 +42,8 @@ pub fn remove(&mut self, index: usize) -> T {
unsafe { unsafe {
self.len -= 1; self.len -= 1;
let result = ptr::read(self.ptr.offset(index as isize)); let result = ptr::read(self.ptr.offset(index as isize));
ptr::copy(self.ptr.offset(index as isize + 1), ptr::copy(self.ptr.as_ptr().offset(index as isize + 1),
self.ptr.offset(index as isize), self.ptr.as_ptr().offset(index as isize),
self.len - index); self.len - index);
result result
} }

5
src/vec-into-iter.md
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@ -73,7 +73,7 @@ impl<T> Vec<T> {
// can't offset off this pointer, it's not allocated! // can't offset off this pointer, it's not allocated!
*ptr *ptr
} else { } else {
ptr.offset(len as isize) ptr.as_ptr().offset(len as isize)
} }
} }
} }
@ -139,7 +139,8 @@ impl<T> Drop for IntoIter<T> {
let elem_size = mem::size_of::<T>(); let elem_size = mem::size_of::<T>();
let num_bytes = elem_size * self.cap; let num_bytes = elem_size * self.cap;
unsafe { unsafe {
heap::deallocate(self.buf.as_ptr() as *mut _, num_bytes, align); let layout = Layout::from_size_align_unchecked(num_bytes, align);
dealloc(self.buf.as_ptr() as *mut _, layout);
} }
} }
} }

4
src/vec-push-pop.md
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@ -22,7 +22,7 @@ pub fn push(&mut self, elem: T) {
if self.len == self.cap { self.grow(); } if self.len == self.cap { self.grow(); }
unsafe { unsafe {
ptr::write(self.ptr.offset(self.len as isize), elem); ptr::write(self.ptr.as_ptr().offset(self.len as isize), elem);
} }
// Can't fail, we'll OOM first. // Can't fail, we'll OOM first.
@ -48,7 +48,7 @@ pub fn pop(&mut self) -> Option<T> {
} else { } else {
self.len -= 1; self.len -= 1;
unsafe { unsafe {
Some(ptr::read(self.ptr.offset(self.len as isize))) Some(ptr::read(self.ptr.as_ptr().offset(self.len as isize)))
} }
} }
} }

35
src/vec-raw.md
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@ -28,21 +28,31 @@ impl<T> RawVec<T> {
let elem_size = mem::size_of::<T>(); let elem_size = mem::size_of::<T>();
let (new_cap, ptr) = if self.cap == 0 { let (new_cap, ptr) = if self.cap == 0 {
let ptr = heap::allocate(elem_size, align); let layout = Layout::from_size_align_unchecked(elem_size, align);
let ptr = alloc(layout);
(1, ptr) (1, ptr)
} else { } else {
let new_cap = 2 * self.cap; let new_cap = self.cap * 2;
let ptr = heap::reallocate(self.ptr.as_ptr() as *mut _, let old_num_bytes = self.cap * elem_size;
self.cap * elem_size, assert!(
new_cap * elem_size, old_num_bytes <= (::std::isize::MAX as usize) / 2,
align); "Capacity overflow!"
);
let num_new_bytes = old_num_bytes * 2;
let layout = Layout::from_size_align_unchecked(old_num_bytes, align);
let ptr = realloc(self.ptr.as_ptr() as *mut _, layout, num_new_bytes);
(new_cap, ptr) (new_cap, ptr)
}; };
// If allocate or reallocate fail, we'll get `null` back // If allocate or reallocate fail, we'll get `null` back
if ptr.is_null() { oom() } if ptr.is_null() {
rust_oom(Layout::from_size_align_unchecked(
new_cap * elem_size,
align,
));
}
self.ptr = Unique::new(ptr as *mut _); self.ptr = Unique::new(ptr as *mut _).unwrap();
self.cap = new_cap; self.cap = new_cap;
} }
} }
@ -56,7 +66,8 @@ impl<T> Drop for RawVec<T> {
let elem_size = mem::size_of::<T>(); let elem_size = mem::size_of::<T>();
let num_bytes = elem_size * self.cap; let num_bytes = elem_size * self.cap;
unsafe { unsafe {
heap::deallocate(self.ptr.as_mut() as *mut _, num_bytes, align); let layout = Layout::from_size_align_unchecked(num_bytes, align);
dealloc(self.ptr.as_ptr() as *mut _, layout);
} }
} }
} }
@ -81,7 +92,7 @@ impl<T> Vec<T> {
} }
// push/pop/insert/remove largely unchanged: // push/pop/insert/remove largely unchanged:
// * `self.ptr -> self.ptr()` // * `self.ptr.as_ptr() -> self.ptr()`
// * `self.cap -> self.cap()` // * `self.cap -> self.cap()`
// * `self.grow -> self.buf.grow()` // * `self.grow -> self.buf.grow()`
} }
@ -123,8 +134,8 @@ impl<T> Vec<T> {
mem::forget(self); mem::forget(self);
IntoIter { IntoIter {
start: *buf.ptr, start: buf.ptr.as_ptr(),
end: buf.ptr.offset(len as isize), end: buf.ptr.as_ptr().offset(len as isize),
_buf: buf, _buf: buf,
} }
} }

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