Intel® Streaming SIMD Extensions 2 (Intel® SSE2) intrinsics for floating-point conversion operations are listed in this topic. The prototypes for Intel® SSE2 intrinsics are in the
To use these intrinsics, include the
immintrin.hfile as follows:
Each conversion intrinsic takes one data type and performs a conversion to a different type. Some conversions, such as those performed by the
_mm_cvtpd_psintrinsic, result in a loss of precision. The rounding mode used in such cases is determined by the value in the
MXCSRregister. The default rounding mode is round-to-nearest.
The rounding mode used by the C and C++ languages when performing a type conversion is to truncate. The
_mm_cvttsd_si32intrinsics use the truncate rounding mode regardless of the mode specified by the
The results of each intrinsic operation are placed in a register. The information about what is placed in each register appears in the tables below, in the detailed explanation for each intrinsic. For each intrinsic, the resulting register is represented by
R3, where each represent the registers in which results are placed.
Corresponding Intel® SSE2 Instruction
Convert DP FP to SP FP
Convert from SP FP to DP FP