vec_gbb

Purpose

Performs a gather-bits-by-bytes operation on the input.

Note: This built-in function is valid when the -mcpu option is set to target POWER8 processors, or higher.

Syntax

d=vec_gbb(a)

Result and argument types

The following table describes the types of the returned value and the function arguments.

Table 1. Result and argument types
d a
vector unsigned long long vector unsigned long long
vector signed long long vector signed long long

Result value

Each doubleword element of the result is set as follows: Let x(i) (0 <= i < 8) denote the byte elements of the corresponding input doubleword element, with x(7) the most significant byte. For each pair of i and j (0 <= i < 8, 0 <= j < 8), the jth bit of the ith byte element of the result is set to the value of the ith bit of the jth byte element of the input.