NAME¶
Scalar_Data_Types - Built-in scalar data types.
DESCRIPTION¶
These are the data types available in the OpenCL C programming language used to
create kernels that are executed on OpenCL device(s). The OpenCL C programming
language (also referred to as OpenCL C) is based on the ISO/IEC 9899:1999 C
language specification (a.k.a. C99 specification) with specific extensions and
restrictions. Please refer to the ISO/IEC 9899:1999 specification for a
detailed description of the language grammar. This section describes
modifications and restrictions to ISO/IEC 9899:1999 supported in OpenCL C.
Most built-in scalar data types are also declared as appropriate
types in the OpenCL API (and header files) that can be used by an
application. The following table describes the built-in scalar data type in
the OpenCL C programming language and the corresponding data type available
to the application:
Type in OpenCL C Language |
Description |
API type for application |
bool |
A conditional data type which is either true or false. The
value true expands to the integer constant 1 and the value
false expands to the integer constant 0. When any scalar value is
converted to bool, the result is 0 if the value compares equal to 0;
otherwise, the result is 1. |
n/a |
char |
A signed two's complement 8-bit integer. |
cl_char |
unsigned char, uchar |
An unsigned 8-bit integer. |
cl_uchar |
short |
A signed two's complement 16-bit integer. |
cl_short |
unsigned short, ushort |
An unsigned 16-bit integer. |
cl_ushort |
int |
A signed two's complement 32-bit integer. |
cl_int |
unsigned int, uint |
An unsigned 32-bit integer. |
cl_uint |
long |
A signed two's complement 64-bit integer. |
cl_long |
unsigned long, ulong |
An unsigned 64-bit integer. |
cl_ulong |
float |
A 32-bit floating point. The float data type must conform to the IEEE
754 single precision storage format. |
cl_float |
double |
A 64-bit floating point. The double data type must conform to the
IEEE 754 double precision storage format. The double scalar type is
an optional type that is supported if CL_DEVICE_DOUBLE_FP_CONFIG
for a device is not zero. See the table for param_name for
clGetDeviceInfo(3clc) for details. |
cl_double |
half |
A 16-bit float. The half data type must conform to the IEEE
754-2008 half precision storage format. |
cl_half |
size_t |
The unsigned integer type of the result of the sizeof operator. This is
a 32-bit unsigned integer if CL_DEVICE_ADDRESS_BITS defined in
clGetDeviceInfo(3clc) is 32-bits and is a 64-bit unsigned integer
if CL_DEVICE_ADDRESS_BITS is 64-bits. |
n/a |
ptrdiff_t |
A signed integer type that is the result of subtracting two pointers.
This is a 32-bit signed integer if CL_DEVICE_ADDRESS_BITS defined
in clGetDeviceInfo(3clc) is 32-bits and is a 64-bit signed integer
if CL_DEVICE_ADDRESS_BITS is 64-bits. |
n/a |
intptr_t |
A signed integer type with the property that any valid pointer to
void can be converted to this type, then converted back to pointer
to void, and the result will compare equal to the original pointer.
This is a 32-bit signed integer if CL_DEVICE_ADDRESS_BITS defined
in table 4.3 is 32-bits and is a 64-bit signed integer if
CL_DEVICE_ADDRESS_BITS is 64-bits. |
n/a |
uintptr_t |
An unsigned integer type with the property that any valid pointer to
void can be converted to this type, then converted back to pointer
to void, and the result will compare equal to the original pointer.
This is a 32-bit signed integer if CL_DEVICE_ADDRESS_BITS defined
in table 4.3 is 32-bits and is a 64-bit signed integer if
CL_DEVICE_ADDRESS_BITS is 64-bits. |
n/a |
void |
The void type comprises an empty set of values; it is an
incomplete type that cannot be completed. |
void |
OPTIONAL HALF FLOATING POINT¶
The half floating-point is supported as an optional extension. An
application that wants to use half and halfn will
need to include the cl_khr_fp16(3clc) directive. This will extended the
list of built-in vector and scalar data types to include the following:
Type in OpenCL Language |
Description |
API type for application |
half2 |
A 2-component half-precision floating-point vector. |
cl_half2 |
half3 |
A 3-component half-precision floating-point vector. |
cl_half3 |
half4 |
A 4-component half-precision floating-point vector. |
cl_half4 |
half8 |
An 8-component half-precision floating-point vector. |
cl_half8 |
half16 |
A 16-component half-precision floating-point vector. |
cl_half16 |
The relational, equality, logical and logical unary operators can
be used with half scalar and halfn vector types
and shall produce a scalar int and vector shortn
result respectively.
The OpenCL compiler accepts an h and H suffix on floating point
literals, indicating the literal is typed as a half.
SPECIFICATION¶
OpenCL Specification[1]
SEE ALSO¶
macroLimits(3clc), vectorDataTypes(3clc),
reservedDataTypes(3clc), otherDataTypes(3clc),
abstractDataTypes(3clc), enums(3clc), cl_khr_fp16(3clc),
cl_khr_fp64(3clc)
AUTHORS¶
The Khronos Group
COPYRIGHT¶
Copyright © 2007-2011 The Khronos Group Inc.
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and/or associated documentation files (the
"Materials"), to deal in the Materials without restriction,
including without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Materials, and to permit
persons to whom the Materials are furnished to do so, subject to the condition
that this copyright notice and permission notice shall be included in all
copies or substantial portions of the Materials.
NOTES¶
- 1.
- OpenCL Specification
page 195, section 6.1.1 - Built-in Scalar Data
Types