# _mm256_inserti128_si256

Inserts 128-bits of packed integer data of the second source vector into the destination vector at a 128-bit offset from imm8[0]. The corresponding Intel® AVX2 instruction is VINSERTI128.

## Syntax

extern __m256i _mm256_inserti128_si256(__m256i a, __m128i b, const int mask);

## Arguments

a | integer source vector
b | integer source vector
mask | integer constant specifying offset

## Description

Inserts 128-bits of packed integer data from the second source operand (third operand) into the destination operand (first operand) at a 128-bit offset from `imm8[0]`. The remaining portions of the destination are written by the corresponding fields of the first source operand (second operand). The high 7 bits of the immediate are ignored.

## Returns

Parent topic: Intrinsics for Insert/Extract Operations