# _mm256_testc_si256

Performs a packed bit test of two integer vectors to set the CF flag. The corresponding Intel® AVX instruction is VPTEST.

## Syntax

extern int _mm256_testc_si256(__m256i s1, __m256i s2);

## Arguments

s1 | first source integer vector
s2 | second source integer vector

## Description

Allows setting of the CF flag. The CF flag is set based on the result of a bitwise AND and logical NOT operation between the first and second source vectors. The corresponding instruction, VPTEST, sets the CF flag if all the resulting bits are 0. If the resulting bits are non-zeros, the instruction clears the CF flag.

## Returns

Non-zero if CF flag is set

Zero if the CF flag is not set

Parent topic: Intrinsics for Packed Test Operations