VCVTTSD2USI—Convert with Truncation Scalar Double-Precision Floating-Point Value to Unsigned Integer

Opcode/

Op /

64/32

CPUID

Description

Instruction En bit Mode Support Feature Flag
EVEX.LLIG.F2.0F.W0 78 /r VCVTTSD2USI r32, xmm1/m64{sae} A V/V AVX512F Convert one double-precision floating-point value from xmm1/m64 to one unsigned doubleword integer r32 using truncation.
EVEX.LLIG.F2.0F.W1 78 /r VCVTTSD2USI r64, xmm1/m64{sae} 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 using truncation.

NOTES: 1. For this specific instruction, EVEX.W 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 with truncation a double-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 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, a truncated (round toward zero) value is returned. 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.

Operation

VCVTTSD2USI (EVEX encoded version)

IF 64-Bit Mode and OperandSize = 64

THEN

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

ELSE

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

FI

Intel C/C++ Compiler Intrinsic Equivalent

VCVTTSD2USI unsigned int _mm_cvttsd_u32(__m128d);

VCVTTSD2USI unsigned int _mm_cvtt_roundsd_u32(__m128d, int sae);

VCVTTSD2USI unsigned __int64 _mm_cvttsd_u64(__m128d);

VCVTTSD2USI unsigned __int64 _mm_cvtt_roundsd_u64(__m128d, int sae);

SIMD Floating-Point Exceptions

Invalid, Precision

Other Exceptions

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