Integer Built-In Functions

Click an item in the table below for details about that function.

abs |x|
abs-diff |x-y| without modulo overflow
add_sat x+y and saturate result
hadd (x+y) >> 1 without modulo overflow
rhadd (x+y+1) >> 1. The intermediate sum does not modulo overflow.
clz Number of leading 0-bits in x
mad_hi mul_hi(a,b)+c
mad24 (Fast integer function.) Multiply 24-bit integer then add the 32-bit result to 32-bit integer
mad_sat a*b+c and saturate the result
max The greater of x or y
min The lessor of x or y
mul_hi High half of the product of x and y
mul24 (Fast integer function.) Multiply 24-bit integer values a and b
rotate result[indx]=v[indx]<<i[indx]
sub_sat x - y and saturate the result
upsample result[i] = ((gentype)hi[i] << 8|16|32) | lo[i]

Description

Built-in integer functions can be used to take scalar or vector arguments. We use the generic type name gentype to indicate that the function can take char, char{2|4|8|16}, uchar, uchar{2|4|8|16}, short, short{2|4|8|16}, ushort, ushort{2|4|8|16}, int, int{2|4|8|16}, uint, uint{2|4|8|16}, long, long{2|4|8|16}, ulong, or ulong{2|4|8|16} as the type for the arguments. We use the generic type name ugentype to refer to unsigned versions of gentype. For example, if gentype is char4, ugentype is uchar4.

For any specific use of a function, the actual type has to be the same for all arguments and the return type unless otherwise specified.

Specification

OpenCL Specification

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