모두의 코드
VCVTTSS2USI (Intel x86/64 assembly instruction)

작성일 : 2020-09-01 이 글은 491 번 읽혔습니다.

VCVTTSS2USI

Convert with Truncation Scalar Single-Precision Floating-Point Value to Unsigned Integer

참고 사항

아래 표를 해석하는 방법은 x86-64 명령어 레퍼런스 읽는 법 글을 참조하시기 바랍니다.

Opcode/
Instruction

Op /
En

64/32
bit Mode
Support

CPUID
Feature
Flag

Description

EVEX.LIG.F3.0F.W0 78 /r
VCVTTSS2USI r32 xmm1/m32{sae}

T1F

V/V

AVX512F

Convert one single-precision floating-point value from xmm1/m32 to one unsigned doubleword integer in r32 using truncation.

EVEX.LIG.F3.0F.W1 78 /r
VCVTTSS2USI r64 xmm1/m32{sae}

T1F

V/N.E.1

AVX512F

Convert one single-precision floating-point value from xmm1/m32 to one unsigned quadword integer in r64 using truncation.


  1. For this specific instruction, EVEX.W in non-64 bit is ignored; the instructions behaves as if the W0 version isused

Instruction Operand Encoding

Op/En Operand 1 Operand 2 Operand 3 Operand 4

T1F ModRM:reg (w) ModRM:r/m (r) NA NA

Description

Converts with truncation a single-precision floating-point value in the source operand (the second operand) to an unsigned doubleword integer (or unsigned quadword integer if operand size is 64 bits) in the destination operand (the first operand). The source operand can be an XMM register or a memory location. The destination operand is a general-purpose register. When the source operand is an XMM register, the single-precision floating-point value is contained in the low doubleword of the register.

When a conversion is inexact, the value returned is rounded according to the rounding control bits in the MXCSR register. If a converted result cannot be represented in the destination format, the floating-point invalid exception is raised, and if this exception is masked, the integer value 2w - 1 is returned, where w represents the number of bits in the destination format.

EVEX.W1 version: promotes the instruction to produce 64-bit data in 64-bit mode.

Note: EVEX.vvvv is reserved and must be 1111b, otherwise instructions will #UD.

Operation

VCVTTSS2USI (EVEX encoded version)

IF 64-bit Mode and OperandSize = 64
THEN
    DEST[63:0] <-  Convert_Single_Precision_Floating_Point_To_UInteger_Truncate(SRC[31:0]);
ELSE
    DEST[31:0] <-  Convert_Single_Precision_Floating_Point_To_UInteger_Truncate(SRC[31:0]);
FI;

Intel C/C++ Compiler Intrinsic Equivalent

VCVTTSS2USI unsigned int _mm_cvttss_u32(__m128 a);
VCVTTSS2USI unsigned int _mm_cvtt_roundss_u32(__m128 a, int sae);
VCVTTSS2USI unsigned __int64 _mm_cvttss_u64(__m128 a);
VCVTTSS2USI unsigned __int64 _mm_cvtt_roundss_u64(__m128 a, int sae);

SIMD Floating-Point Exceptions

Invalid, Precision

Other Exceptions

EVEX-encoded instructions, see Exceptions Type E3NF.

첫 댓글을 달아주세요!
프로필 사진 없음
강좌에 관련 없이 궁금한 내용은 여기를 사용해주세요

    댓글을 불러오는 중입니다..