_mm_cvtt_ps2pi
Microsoft Specific
Generates the Convert Packed Single-Precision Floating-Point Values to Packed Doubleword Integers (cvtps2pi) instruction, which converts the floating-point values in the first two elements in the __m128 structure value to 32-bit integers and returns an __m64 structure containing the two 32-bit integers.
__m64 _mm_cvtt_ps2pi( __m128 value );
Parameters
- [in] value
-
An __m128 structure containing four single-precision floating-point values.
This intrinsic differs from _mm_cvt_ps2pi only in that the floating-point values are truncated rather than rounded according to the setting of the MXCSR register.
Because __m128 represents an XMM register and __m64 represents an MMX register, this intrinsic generates an instruction that operates on these registers directly and does not involve system memory.
This routine is only available as an intrinsic.
// _mm_cvtt_ps2pi.cpp
// processor: x86
#include <intrin.h>
#include <stdio.h>
#pragma intrinsic(_mm_cvtt_ps2pi)
int main()
{
__m128 a;
__m64 b;
float af[4] = { 101.5, 200.5,300.5, 400.5 };
// Load a with the floating point values
// _mm_loadu_ps allowed unaligned addresses
a = _mm_loadu_ps(af);
//
b = _mm_cvtt_ps2pi(a);
// Return to floating point
_mm_empty();
// Print out the values in b
printf_s("%d %d\n", b.m64_i32[0], b.m64_i32[1]);
}
Output
101 200
