Intel 253666-024US Manuel D’Utilisation

Page de 760
Vol. 2A 3-39
INSTRUCTION SET REFERENCE, A-M
ADDSD—Add Scalar Double-Precision Floating-Point Values
ADDSD—Add Scalar Double-Precision Floating-Point Values
Description
Adds the low double-precision floating-point values from the source operand (second 
operand) and the destination operand (first operand), and stores the double-preci-
sion floating-point result in the destination operand. 
The source operand can be an XMM register or a 64-bit memory location. The desti-
nation operand is an XMM register. The high quadword of the destination operand 
remains unchanged. See Chapter 11 in the Intel® 64 and IA-32 Architectures Soft-
ware Developer’s Manual, Volume 1
, for an o
verview of a scalar double-precision 
floating-point operation.
In 64-bit mode, using a REX prefix in the form of REX.R permits this instruction to 
access additional registers (XMM8-XMM15).
Operation
DEST[63:0] ← DEST[63:0] 
+
 SRC[63:0];
(* DEST[127:64] unchanged *)
Intel C/C++ Compiler Intrinsic Equivalent
ADDSD
__m128d _mm_add_sd (m128d a, m128d b)
SIMD Floating-Point Exceptions
Overflow, Underflow, Invalid, Precision, Denormal.
Protected Mode Exceptions
#GP(0)
For an illegal memory operand effective address in the CS, DS, 
ES, FS or GS segments.
#SS(0) 
For an illegal address in the SS segment.
#PF(fault-code) 
For a page fault.
#NM
If CR0.TS[bit 3] = 1. 
#XM 
If an unmasked SIMD floating-point exception and CR4.OSXM-
MEXCPT[bit 10] = 1. 
Opcode
Instruction
64-Bit 
Mode
Compat/
Leg Mode
Description
F2 0F 58 /r ADDSD xmm1xmm2/m64 Valid
Valid
Add the low double-
precision floating-point 
value from xmm2/m64 to 
xmm1.