_mm_cvttss_si64
Microsoft Specific
Emits the Streaming SIMD Extensions (SSE) instruction cvttss2si. This instruction extracts a 32-bit floating point value and converts it to a signed 64-bit integer using truncation.
__int64 _mm_cvttss_si64(
__m128 a
);
Parameters
- [in] a
A 128-bit parameter that contains a floating point value in the lowest 32-bits.
Return value
The result can be expressed with the following equation:
r := CVT(TRUNCATE(a0))
Requirements
Intrinsic |
Architecture |
|---|---|
_mm_cvttss_si64 |
x64 |
Header file <xmmintrin.h>
Remarks
r is the 64-bit signed integer result. a0 is the lower 32 bits of parameter a. The upper 96 bits of a are ignored.
Before you use this intrinsic, software must ensure that the processor supports the instruction.
Example
#include <stdio.h>
#include <xmmintrin.h>
int main ()
{
__m128 a;
a.m128_f32[0] = 100.5;
__int64 res = _mm_cvttss_si64(a);
printf_s("Original a: %f\n", a.m128_f32[0]);
printf_s("Result res: %I64d\n", res);
return 0;
}
Original a: 100.500000 Result res: 100