pub struct DevicePointer<T: ?Sized + DeviceCopy> { /* private fields */ }Expand description
A pointer to device memory.
DevicePointer cannot be dereferenced by the CPU, as it is a pointer to a memory allocation in
the device. It can be safely copied to the device (eg. as part of a kernel launch) and either
unwrapped or transmuted to an appropriate pointer.
DevicePointer is guaranteed to have an equivalent internal representation to a raw pointer.
Thus, it can be safely reinterpreted or transmuted to *mut T. It is safe to pass a
DevicePointer through an FFI boundary to C code expecting a *mut T, so long as the code on
the other side of that boundary does not attempt to dereference the pointer on the CPU. It is
thus possible to pass a DevicePointer to a CUDA kernel written in C.
Implementations§
Source§impl<T: ?Sized + DeviceCopy> DevicePointer<T>
impl<T: ?Sized + DeviceCopy> DevicePointer<T>
Sourcepub fn as_ptr(&self) -> *const T
pub fn as_ptr(&self) -> *const T
Returns a rust pointer created from this pointer, meant for FFI purposes.
The pointer is not dereferenceable from the CPU!
Sourcepub fn as_mut_ptr(&self) -> *mut T
pub fn as_mut_ptr(&self) -> *mut T
Returns a rust pointer created from this pointer, meant for FFI purposes.
The pointer is not dereferenceable from the CPU!
Sourcepub fn as_raw(&self) -> CUdeviceptr
pub fn as_raw(&self) -> CUdeviceptr
Returns the contained CUdeviceptr.
Sourcepub fn from_raw(ptr: CUdeviceptr) -> Self
pub fn from_raw(ptr: CUdeviceptr) -> Self
Create a DevicePointer from a raw CUDA pointer
Sourcepub fn is_null(self) -> bool
pub fn is_null(self) -> bool
Returns true if the pointer is null.
§Examples
use cust::memory::*;
use std::ptr;
unsafe {
let null : *mut u64 = ptr::null_mut();
assert!(DevicePointer::wrap(null).is_null());
}Sourcepub unsafe fn offset(self, count: isize) -> Selfwhere
T: Sized,
pub unsafe fn offset(self, count: isize) -> Selfwhere
T: Sized,
Calculates the offset from a device pointer.
count is in units of T; eg. a count of 3 represents a pointer offset of
3 * size_of::<T>() bytes.
§Safety
If any of the following conditions are violated, the result is Undefined Behavior:
-
Both the starting and resulting pointer must be either in bounds or one byte past the end of the same allocated object.
-
The computed offset, in bytes, cannot overflow an
isize. -
The offset being in bounds cannot rely on “wrapping around” the address space. That is, the infinite-precision sum, in bytes must fit in a usize.
Consider using wrapping_offset instead if these constraints are
difficult to satisfy. The only advantage of this method is that it
enables more aggressive compiler optimizations.
§Examples
use cust::memory::*;
unsafe {
let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
let offset = dev_ptr.offset(1); // Points to the 2nd u64 in the buffer
cuda_free(dev_ptr); // Must free the buffer using the original pointer
}Sourcepub fn wrapping_offset(self, count: isize) -> Selfwhere
T: Sized,
pub fn wrapping_offset(self, count: isize) -> Selfwhere
T: Sized,
Calculates the offset from a device pointer using wrapping arithmetic.
count is in units of T; eg. a count of 3 represents a pointer offset of
3 * size_of::<T>() bytes.
§Safety
The resulting pointer does not need to be in bounds, but it is
potentially hazardous to dereference (which requires unsafe).
In particular, the resulting pointer may not be used to access a
different allocated object than the one self points to. In other
words, x.wrapping_offset(y.wrapping_offset_from(x)) is
not the same as y, and dereferencing it is undefined behavior
unless x and y point into the same allocated object.
Always use .offset(count) instead when possible, because offset
allows the compiler to optimize better. If you need to cross object
boundaries, cast the pointer to an integer and do the arithmetic there.
§Examples
use cust::memory::*;
unsafe {
let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
let offset = dev_ptr.wrapping_offset(1); // Points to the 2nd u64 in the buffer
cuda_free(dev_ptr); // Must free the buffer using the original pointer
}Sourcepub unsafe fn add(self, count: usize) -> Selfwhere
T: Sized,
pub unsafe fn add(self, count: usize) -> Selfwhere
T: Sized,
Calculates the offset from a pointer (convenience for .offset(count as isize)).
count is in units of T; e.g. a count of 3 represents a pointer
offset of 3 * size_of::<T>() bytes.
§Safety
If any of the following conditions are violated, the result is Undefined Behavior:
-
Both the starting and resulting pointer must be either in bounds or one byte past the end of an allocated object.
-
The computed offset, in bytes, cannot overflow an
isize. -
The offset being in bounds cannot rely on “wrapping around” the address space. That is, the infinite-precision sum must fit in a
usize.
Consider using wrapping_offset instead if these constraints are
difficult to satisfy. The only advantage of this method is that it
enables more aggressive compiler optimizations.
§Examples
use cust::memory::*;
unsafe {
let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
let offset = dev_ptr.add(1); // Points to the 2nd u64 in the buffer
cuda_free(dev_ptr); // Must free the buffer using the original pointer
}Sourcepub unsafe fn sub(self, count: usize) -> Selfwhere
T: Sized,
pub unsafe fn sub(self, count: usize) -> Selfwhere
T: Sized,
Calculates the offset from a pointer (convenience for
.offset((count as isize).wrapping_neg())).
count is in units of T; e.g. a count of 3 represents a pointer
offset of 3 * size_of::<T>() bytes.
§Safety
If any of the following conditions are violated, the result is Undefined Behavior:
-
Both the starting and resulting pointer must be either in bounds or one byte past the end of an allocated object.
-
The computed offset, in bytes, cannot overflow an
isize. -
The offset being in bounds cannot rely on “wrapping around” the address space. That is, the infinite-precision sum must fit in a
usize.
Consider using wrapping_offset instead if these constraints are
difficult to satisfy. The only advantage of this method is that it
enables more aggressive compiler optimizations.
§Examples
use cust::memory::*;
unsafe {
let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
let offset = dev_ptr.add(4).sub(3); // Points to the 2nd u64 in the buffer
cuda_free(dev_ptr); // Must free the buffer using the original pointer
}Sourcepub fn wrapping_add(self, count: usize) -> Selfwhere
T: Sized,
pub fn wrapping_add(self, count: usize) -> Selfwhere
T: Sized,
Calculates the offset from a pointer using wrapping arithmetic.
(convenience for .wrapping_offset(count as isize))
count is in units of T; e.g. a count of 3 represents a pointer
offset of 3 * size_of::<T>() bytes.
§Safety
The resulting pointer does not need to be in bounds, but it is potentially hazardous to dereference.
Always use .add(count) instead when possible, because add
allows the compiler to optimize better.
§Examples
use cust::memory::*;
unsafe {
let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
let offset = dev_ptr.wrapping_add(1); // Points to the 2nd u64 in the buffer
cuda_free(dev_ptr); // Must free the buffer using the original pointer
}Sourcepub fn wrapping_sub(self, count: usize) -> Selfwhere
T: Sized,
pub fn wrapping_sub(self, count: usize) -> Selfwhere
T: Sized,
Calculates the offset from a pointer using wrapping arithmetic.
(convenience for .wrapping_offset((count as isize).wrapping_sub()))
count is in units of T; e.g. a count of 3 represents a pointer
offset of 3 * size_of::<T>() bytes.
§Safety
The resulting pointer does not need to be in bounds, but it is
potentially hazardous to dereference (which requires unsafe).
Always use .sub(count) instead when possible, because sub
allows the compiler to optimize better.
§Examples
use cust::memory::*;
unsafe {
let mut dev_ptr = cuda_malloc::<u64>(5).unwrap();
let offset = dev_ptr.wrapping_add(4).wrapping_sub(3); // Points to the 2nd u64 in the buffer
cuda_free(dev_ptr); // Must free the buffer using the original pointer
}Sourcepub fn cast<U: DeviceCopy>(self) -> DevicePointer<U>
pub fn cast<U: DeviceCopy>(self) -> DevicePointer<U>
Casts this device pointer to another type.
Trait Implementations§
Source§impl<T: Clone + ?Sized + DeviceCopy> Clone for DevicePointer<T>
impl<T: Clone + ?Sized + DeviceCopy> Clone for DevicePointer<T>
Source§fn clone(&self) -> DevicePointer<T>
fn clone(&self) -> DevicePointer<T>
1.0.0 · Source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read more