_mm_floor_sd
Microsoft Specific
Emits the Streaming SIMD Extensions 4 (SSE4) instruction roundsd. This instruction rounds a parameter down. The rounded value replaces the lower 64 bits of the other parameter.
__m128d _mm_floor_sd(
__m128d a,
__m128d b
);
Parameters
[in] a
A 128-bit parameter that contains two 64-bit floating point values.[in] b
A 128-bit parameter that contains a floating point value in the lowest 64 bits.
Return value
The result can be expressed with the following equations:
r0 := FLOOR(b0)
r1 := a1
Requirements
Intrinsic |
Architecture |
|---|---|
_mm_floor_sd |
x86, x64 |
Header file <smmintrin.h>
Remarks
r0, a0, and b0 are the lower 64 bits of return value r and parameters a and b. r1, a1, and b1 are the higher 64 bits of return value r and parameters a and b.
This function is implemented as a macro that invokes intrinsic _mm_round_sd.
Before you use this intrinsic, software must ensure that the processor supports the instruction.
Example
#include <stdio.h>
#include <smmintrin.h>
int main ()
{
__m128d a, b;
a.m128d_f64[0] = 0.0;
a.m128d_f64[1] = 500.25;
b.m128d_f64[0] = -0.0625;
b.m128d_f64[1] = 0.0;
__m128d res = _mm_floor_sd(a, b);
printf_s("Original a: %I64f\t%I64f\nOriginal b: %I64f\t%I64f\n",
a.m128d_f64[0], a.m128d_f64[1], b.m128d_f64[0], b.m128d_f64[1]);
printf_s("Result res: %I64f\t%I64f\n",
res.m128d_f64[0], res.m128d_f64[1]);
return 0;
}
Original a: 0.000000 500.250000
Original b: -0.062500 0.000000
Result res: -1.000000 500.250000