# VCVTSD2USI—Convert Scalar Double-Precision Floating-Point Value to Unsigned Doubleword Integer

Opcode/Instruction |
Op /En |
64/32 bit Mode Support |
CPUID Feature Flag |
Description |

EVEX.LLIG.F2.0F.W0 79 /r VCVTSD2USI r32, xmm1/m64{er} |
A |
V/V |
AVX512F |
Convert one double-precision floating-point value from xmm1/m64 to one unsigned doubleword integer r32. |

EVEX.LLIG.F2.0F.W1 79 /r VCVTSD2USI r64, xmm1/m64{er} |
A |
V/N.E.^{1} |
AVX512F |
Convert one double-precision floating-point value from xmm1/m64 to one unsigned quadword integer zero-extended into r64. |

**NOTES: 1. EVEX.W1 in non-64 bit is ignored; the instructions behaves as if the W0 version is used.**

### Instruction Operand Encoding

Op/En |
Tuple Type |
Operand 1 |
Operand 2 |
Operand 3 |
Operand 4 |

A |
Tuple1 Fixed |
ModRM:reg (w) |
ModRM:r/m (r) |
NA |
NA |

**Description**

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

When a conversion is inexact, the value returned is rounded according to the rounding control bits in the MXCSR register or the embedded rounding control bits. 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 2^{w} – 1 is returned, where w represents the number of bits in the destination format.

**Operation**

**VCVTSD2USI (EVEX encoded version)**

IF (SRC *is register*) AND (EVEX.b = 1)

THEN

SET_ROUNDING_MODE_FOR_THIS_INSTRUCTION(EVEX.RC);

ELSE

SET_ROUNDING_MODE_FOR_THIS_INSTRUCTION(MXCSR.RC);

FI;

IF 64-Bit Mode and OperandSize = 64

THEN

DEST[63:0] := Convert_Double_Precision_Floating_Point_To_UInteger(SRC[63:0]);

ELSE

DEST[31:0] := Convert_Double_Precision_Floating_Point_To_UInteger(SRC[63:0]);

FI

**Intel C/C++ Compiler Intrinsic Equivalent**

VCVTSD2USI unsigned int _mm_cvtsd_u32(__m128d);

VCVTSD2USI unsigned int _mm_cvt_roundsd_u32(__m128d, int r);

VCVTSD2USI unsigned __int64 _mm_cvtsd_u64(__m128d);

VCVTSD2USI unsigned __int64 _mm_cvt_roundsd_u64(__m128d, int r);

**SIMD Floating-Point Exceptions**

Invalid, Precision

**Other Exceptions**

EVEX-encoded instructions, see Table 2-48, “Type E3NF Class Exception Conditions”.