Intel 253666-024US Manuel D’Utilisation

Page de 760
3-198 Vol. 2A
CVTPD2PI—Convert Packed Double-Precision Floating-Point Values to Packed Double-
word Integers
INSTRUCTION SET REFERENCE, A-M
CVTPD2PI—Convert Packed Double-Precision Floating-Point Values to 
Packed Doubleword Integers
Description
Converts two packed double-precision floating-point values in the source operand 
(second operand) to two packed signed doubleword integers in the destination 
operand (first operand).
The source operand can be an XMM register or a 128-bit memory location. The desti-
nation operand is an MMX technology 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 is larger than the 
maximum signed doubleword integer, the floating-point invalid exception is raised, 
and if this exception is masked, the indefinite integer value (80000000H) is returned.
This instruction causes a transition from x87 FPU to MMX technology operation (that 
is, the x87 FPU top-of-stack pointer is set to 0 and the x87 FPU tag word is set to all 
0s [valid]). If this instruction is executed while an x87 FPU floating-point exception is 
pending, the exception is handled before the CVTPD2PI instruction is executed.
In 64-bit mode, use of the REX.R prefix permits this instruction to access additional 
registers (XMM8-XMM15).
Operation
DEST[31:0] ← Convert_Double_Precision_Floating_Point_To_Integer(SRC[63:0]);
DEST[63:32]  ← Convert_Double_Precision_Floating_Point_To_Integer(SRC[127:64]);
Intel C/C++ Compiler Intrinsic Equivalent
CVTPD1PI
__m64 _mm_cvtpd_pi32(__m128d a)
SIMD Floating-Point Exceptions
Invalid, Precision.
Opcode
Instruction
64-Bit Mode
Compat/
Leg Mode
Description
66 0F 2D /CVTPD2PI mm
xmm/m128
Valid
Valid
Convert two packed double-
precision floating-point 
values from xmm/m128 to 
two packed signed 
doubleword integers in mm.