OpenCL 1.2

Supported Data Types

The optional double scalar and vector types are supported if CL_DEVICE_DOUBLE_FP_CONFIG is not zero.

Built-in Scalar Data Types
OpenCL Type API Type Description
bool true (1) or false (0)
char cl_char 8-bit signed
unsigned char, uchar cl_uchar 8-bit unsigned
short cl_short 16-bit signed
unsigned short, ushort cl_ushort 16-bit unsigned
int cl_int 32-bit signed
unsigned int, uint cl_uint 32-bit unsigned
long cl_long 64-bit signed
unsigned long, ulong cl_ulong 64-bit unsigned
float cl_float 32-bit float
double (OPTIONAL) cl_double 64-bit. IEEE 754
half cl_half 16-bit float (storage only)
size_t 32- or 64-bit unsigned integer
ptrdiff_t 32- or 64-bit signed integer
intptr_t 32- or 64-bit signed integer
uintptr_t 32- or 64-bit unsigned integer
void void void
Built-in Vector Data Types
OpenCL Type API Type Description
charn cl_charn 8-bit signed
ucharn cl_ucharn 8-bit unsigned
shortn cl_shortn 16-bit signed
ushortn cl_ushortn 16-bit unsigned
intn cl_intn 32-bit signed
uintn cl_uintn 32-bit unsigned
longn cl_longn 64-bit signed
ulongn cl_ulongn 64-bit unsigned
floatn cl_floatn 32-bit float
doublen (OPTIONAL) cl_doublen 64-bit float

Other Built-in Data Types

The optional types listed here other than event_t are only defined if CL_DEVICE_IMAGE_SUPPORT is CL_TRUE.

Other Built-in Data Types
OpenCL Type Description
image2d_t (OPTIONAL) 2D image handle
image3d_t (OPTIONAL) 3D image handle
image2d_array_t (OPTIONAL) 2D image array
image1d_t (OPTIONAL) 1D image handle
image1d_buffer_t (OPTIONAL) 1D image buffer
image1d_array_t (OPTIONAL) 1D image array
sampler_t (OPTIONAL) sampler handle
event_t event handle

Reserved Data Types

Reserved Data Types
OpenCL Type Description
booln boolean vector
halfn 16-bit, vector
quad, quadn 128-bit float, vector
complex half, complex halfn imaginary half, imaginary halfn 16-bit complex, vector
complex float, complex floatn imaginary float, imaginary floatn 32-bit complex, vector
complex double, complex doublen imaginary double, imaginary doublen 64-bit complex, vector
complex quad, complex quadn imaginary quad, imaginary quadn 128-bit complex, vector
floatnxm n*m matrix of 32-bit floats
doublenxm n*m matrix of 64-bit floats

Vector Component Addressing

Vector Components

  0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
float2 v;
v.x v.y  
v.s0 v.s1
float3 v;
v.x v.y v.z  
v.s0 v.s1 v.s2
float4 v;
v.x v.y v.z v.w  
v.s0 v.s1 v.s2 v.s3
float8 v; v.s0 v.s1 v.s2 v.s3 v.s4 v.s5 v.s6 v.s7                
float16 v;
v.s9 v.sf
v.sA v.sB v.sC v.sD v.sE v.sF

Vector Addressing Equivalences

Numeric indices are preceded by the letter s or S, e.g.: s1. Swizzling, duplication, and nesting are allowed, e.g.: v.yx, v.xx, v.lo.x

  v.lo v.hi v.odd v.even
v.x v.y v.y v.x
v.s0 v.s1 v.s1 v.s0
v.xy v.yw v.xz
v.s01 v.s23 v.s13 v.s02
v.xy v.yw v.xz
v.s01 v.s23 v.s13 v.s02
float8 v.s0123 v.s4567 v.s1357 v.s0246
float16 v.s01234567 v.s89abcdef v.s13579bdf v.s02468ace
  1. When using .lo or .hi with a 3-component vector, the .w component is undefined.

Operators and Qualifiers


These operators behave similarly as in C99 except that operands may include vector types when possible:

+ - * % / -- ++ == != &
~ ^ > < >= <= | ! && ||
?: >> << = , op= sizeof

Address Space Qualifiers

  • __global, global
  • __constant, constant
  • __local, local
  • __private, private

Function Qualifiers

  • __kernel, kernel
  • __attribute__((vec_type_hint(type))) //type defaults to int
  • __attribute__((work_group_size_hint(X, Y, Z)))
  • __attribute__((reqd_work_group_size(X, Y, Z)))

Specify Type Attributes

Use to specify special attributes of enum, struct and union types

  • __attribute__((aligned(n)))
  • __attribute__((aligned))
  • __attribute__((packed))
  • __attribute__((endian(host)))
  • __attribute__((endian(device)))
  • __attribute__((endian))

Math Constants

The values of the following symbolic constants are type float, accurate within the precision of a single precision floating-point number.

MAXFLOAT Value of maximum noninfinite single-precision floating-point number.
HUGE_VALF Positive float expression, evaluates to +infinity.
HUGE_VAL Positive double expression, evals. to +infinity. OPTIONAL
INFINITY Constant float expression, positive or unsigned infinity.
NAN Constant float expression, quiet NaN.

When double is supported, macros ending in _F are available in type double by removing _F from the macro name, and in type half when the half extension is enabled by replacing _F with _H.

M_E_F Value of e
M_LOG2E_F Value of log2e
M_LOG10E_F Value of log10e
M_LN2_F Value of loge2
M_LN10_F Value of loge10
M_PI_F Value of π
M_PI_2_F Value of π / 2
M_PI_4_F Value of π / 4
M_1_PI_F Value of 1 / π
M_2_PI_F Value of 2 / π
M_2_SQRTPI_F Value of 2 / √π
M_SQRT2_F Value of √2
M_SQRT1_2_F Value of 1 / √2

OpenCL Device Architecture Diagram

  Global Constant Local Private
Dynamic allocation Dynamic allocation Dynamic allocation No allocation
Read/Write access Read/Write access No access No access
No allocation Static allocation Static allocation Static allocation
Read/Write access Read-only access Read/Write access Read/Write access

This conceptual OpenCL device architecture diagram shows processing elements (PE), compute units (CU), and devices. The host is not shown. OpenCL 1.2 Device Architecture Diagram