CVTSD2SI — Convert Scalar Double Precision Floating-Point Value to Doubleword Integer

Opcode/Instruction Op / En 64/32 bit Mode Support CPUID Feature Flag Description
F2 0F 2D /r CVTSD2SI r32, xmm1/m64 A V/V SSE2 Convert one double precision floating-point value from xmm1/m64 to one signed doubleword integer r32.
F2 REX.W 0F 2D /r CVTSD2SI r64, xmm1/m64 A V/N.E. SSE2 Convert one double precision floating-point value from xmm1/m64 to one signed quadword integer sign-extended into r64.
VEX.LIG.F2.0F.W0 2D /r 1 VCVTSD2SI r32, xmm1/m64 A V/V AVX Convert one double precision floating-point value from xmm1/m64 to one signed doubleword integer r32.
VEX.LIG.F2.0F.W1 2D /r 1 VCVTSD2SI r64, xmm1/m64 A V/N.E.2 AVX Convert one double precision floating-point value from xmm1/m64 to one signed quadword integer sign-extended into r64.
EVEX.LLIG.F2.0F.W0 2D /r VCVTSD2SI r32, xmm1/m64{er} B V/V AVX512F Convert one double precision floating-point value from xmm1/m64 to one signed doubleword integer r32.
EVEX.LLIG.F2.0F.W1 2D /r VCVTSD2SI r64, xmm1/m64{er} B V/N.E.2 AVX512F Convert one double precision floating-point value from xmm1/m64 to one signed quadword integer sign-extended into r64.

1. Software should ensure VCVTSD2SI is encoded with VEX.L=0. Encoding VCVTSD2SI with VEX.L=1 may encounter unpredictable behavior across different processor generations.

2. VEX.W1/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 N/A ModRM:reg (w) ModRM:r/m (r) N/A N/A
B Tuple1 Fixed ModRM:reg (w) ModRM:r/m (r) N/A N/A

Description

Converts a double precision floating-point value in the source operand (the second operand) to a signed double-word integer in the destination operand (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.

If a converted result exceeds the range limits of signed doubleword integer (in non-64-bit modes or 64-bit mode with REX.W/VEX.W/EVEX.W=0), the floating-point invalid exception is raised, and if this exception is masked, the indefinite integer value (80000000H) is returned.

If a converted result exceeds the range limits of signed quadword integer (in 64-bit mode and REX.W/VEX.W/EVEX.W = 1), the floating-point invalid exception is raised, and if this exception is masked, the indefinite integer value (80000000_00000000H) is returned.

Legacy SSE instruction: Use of the REX.W prefix promotes the instruction to produce 64-bit data in 64-bit mode. See the summary chart at the beginning of this section for encoding data and limits.

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

Software should ensure VCVTSD2SI is encoded with VEX.L=0. Encoding VCVTSD2SI with VEX.L=1 may encounter unpredictable behavior across different processor generations.

Operation

VCVTSD2SI (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_Integer(SRC[63:0]);
    ELSE DEST[31:0] := Convert_Double_Precision_Floating_Point_To_Integer(SRC[63:0]);
FI

(V)CVTSD2SI

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

Intel C/C++ Compiler Intrinsic Equivalent

VCVTSD2SI int _mm_cvtsd_i32(__m128d);
VCVTSD2SI int _mm_cvt_roundsd_i32(__m128d, int r);
VCVTSD2SI __int64 _mm_cvtsd_i64(__m128d);
VCVTSD2SI __int64 _mm_cvt_roundsd_i64(__m128d, int r);
CVTSD2SI __int64 _mm_cvtsd_si64(__m128d);
CVTSD2SI int _mm_cvtsd_si32(__m128d a)

SIMD Floating-Point Exceptions

Invalid, Precision.

Other Exceptions

VEX-encoded instructions, see Table 2-20, “Type 3 Class Exception Conditions.”

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

Additionally:

#UD If VEX.vvvv != 1111B or EVEX.vvvv != 1111B.