_mm_blendv_pd
Microsoft Specific
Emits the Streaming SIMD Extensions 4 (SSE4) instruction blendvpd. This function blends packed double precision floating point values.
__m128d _mm_blendv_pd(
__m128d a,
__m128d b,
__m128d mask
);
Parameters
[in] a
A 128-bit parameter that contains two 64-bit floating point values to be blended.[in] b
A 128-bit parameter that contains two 64-bit floating point values to be blended.[in] mask
A 128-bit mask that selects components for the blend operation.
Return value
r0 := (mask0 & 0x8000000000000000) ? b0 : a0
r1 := (mask1 & 0x8000000000000000) ? b1 : a1
Requirements
Intrinsic |
Architecture |
|---|---|
_mm_blendv_pd |
x86, x64 |
Header file <smmintrin.h>
Remarks
r0, a0, b0, and mask0 are the low order 64 bits of return value r and parameters a, b, and mask. r1, a1, b1, and mask1 are the high order 64 bits of return value r and parameters a, b, and mask.
Before using this intrinsic, software must ensure that the processor supports the instruction.
Example
#include <stdio.h>
#include <smmintrin.h>
int main () {
__m128d a, b, mask;
unsigned __int64 maskValue = 0x8000000000000000;
mask.m128d_f64[1] = *reinterpret_cast<double *>(&maskValue);
mask.m128d_f64[0] = 0x0000000000000000;
a.m128d_f64[1] = -500.17;
a.m128d_f64[0] = -21734.56;
b.m128d_f64[1] = 3.141592;
b.m128d_f64[0] = 10.5;
__m128d res = _mm_blendv_pd( a, b, mask );
printf_s("Original a: %14f %14f\nOriginal b: %14f %14f\n",
a.m128d_f64[1], a.m128d_f64[0],
b.m128d_f64[1], b.m128d_f64[0]);
printf_s("Result res: %14f %14f\n",
res.m128d_f64[1], res.m128d_f64[0]);
return 0;
}
Original a: -500.170000 -21734.560000
Original b: 3.141592 10.500000
Result res: 3.141592 -21734.560000