# _mm256_blend_pd

Performs a conditional blend/merge of float64 vectors. The corresponding Intel® AVX instruction is VBLENDPD.

## Syntax

extern __m256d _mm256_blend_pd(__m256d m1, __m256d m2, const int mask);

## Arguments

m1 | float64 vector used for the operation
m2 | float64 vector also used for the operation
mask | a constant of integer type that is the mask for the operation

## Description

Performs a conditional merge of four packed double-precision floating point elements (float64 elements) of two vectors according to the immediate bits of the mask parameter.

The mask parameter defines a constant integer. The immediate bits [3:0] in the mask determine from which source vector elements are copied into the resulting vector.

If the bits in mask are “1” then the corresponding elements of the second source vector are copied into the resulting vector. If the bits are “0” then the corresponding elements of the first source vector are copied into the resulting vector. Thus a merging/blending of the elements of the two source vectors occurs when this intrinsic is used.

## Returns

Result of the merge/blend operation.

Parent topic: Intrinsics for Blend and Conditional Merge Operations