Term | CUDA | HIP | OpenCL |
---|---|---|---|
Device | int deviceId |
int deviceId |
cl_device |
Queue | cudaStream_t |
hipStream_t |
cl_command_queue |
Event | cudaEvent_t |
hipEvent_t |
cl_event |
Memory | void * |
void * |
cl_mem |
grid | grid | NDRange | |
block | block | work-group | |
thread | thread | work-item | |
warp | warp | sub-group | |
Thread- index |
threadIdx.x |
threadIdx.x |
get_local_id(0) |
Block- index |
blockIdx.x |
blockIdx.x |
get_group_id(0) |
Block- dim |
blockDim.x |
blockDim.x |
get_local_size(0) |
Grid-dim | gridDim.x |
gridDim.x |
get_num_groups(0) |
Device Kernel | __global__ |
__global__ |
__kernel |
Device Function | __device__ |
__device__ |
Implied in device compilation |
Host Function | __host_ (default) |
__host_ (default) |
Implied in host compilation |
Host + Device Function | __host__ __device__ |
__host__ __device__ |
No equivalent |
Kernel Launch | <<< >>> |
hipLaunchKernel /hipLaunchKernelGGL /<<< >>> |
clEnqueueNDRangeKernel |
Global Memory | __global__ |
__global__ |
__global |
Group Memory | __shared__ |
__shared__ |
__local |
Constant | __constant__ |
__constant__ |
__constant |
__syncthreads |
__syncthreads |
barrier(CLK_LOCAL_MEMFENCE) |
|
Atomic Builtins | atomicAdd |
atomicAdd |
atomic_add |
Precise Math | cos(f) |
cos(f) |
cos(f) |
Fast Math | __cos(f) |
__cos(f) |
native_cos(f) |
Vector | float4 |
float4 |
float4 |
The indexing functions (starting with thread-index
) show the terminology for a 1D grid. Some APIs use reverse order of xyz
/ 012 indexing for 3D grids.