This chapter is from the book
This chapter is from the book
This chapter is from the book
This chapter is from the book
Other Data Types
The other data types supported by OpenCL C are described in Table 4.6.
Table 4.6. Other Built-In Data Types
|
Type |
Description |
|
image2d_t |
A 2D image type. |
|
image3d_t |
A 3D image type. |
|
sampler_t |
An image sampler type. |
|
event_t |
An event type. These are used by built-in functions that perform async copies from global to local memory and vice versa. Each async copy operation returns an event and takes an event to wait for that identifies a previous async copy operation. |
There are a few restrictions on the use of image and sampler types:
- The image and samplers types are defined only if the device supports images.
- Image and sampler types cannot be declared as arrays. Here are a couple of examples that show these illegal use cases:
kernel void foo(image2d_t imgA[10]) // error. images cannot be declared // as arrays { image2d_t imgB[4]; // error. images cannot be declared // as arrays ... } kernel void foo(sampler_t smpA[10]) // error. samplers cannot be declared // as arrays { sampler_t smpB[4]; // error. samplers cannot be declared // as arrays ... } - The image2d_t, image3d_t, and sampler_t data types cannot be declared in a struct.
- Variables cannot be declared to be pointers of image2d_t, image3d_t, and sampler_t data types.