x86 Instruction Set Reference

ADDSD

Add Scalar Double-Precision Floating-Point Values

Opcode	Mnemonic	Description
`F2 0F 58 /r`	`ADDSD xmm1, xmm2/m64`	Add the low double-precision floating-point value from xmm2/m64 to xmm1.

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-precision floating-point result in the destination operand. The source operand can be an XMM register or a 64-bit memory location. The destination operand is an XMM register. The high quadword of the destination operand remains unchanged.

Operation
Destination[0..63] = Destination[0..63] + Source[0..63]; //Destination[64..127] remains unchanged

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.
`#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 TS in CR0 is set.
`#XM`	If an unmasked SIMD floating-point exception and OSXMMEXCPT in CR4 is 1.
`#UD`	If an unmasked SIMD floating-point exception and OSXMMEXCPT in CR4 is 0. If EM in CR0 is set. If OSFXSR in CR4 is 0. If CPUID feature flag SSE2 is 0.

Real-Address Mode Exceptions

`#GP(0)`	If any part of the operand lies outside the effective address space from 0 to FFFFH.
`#GP(0)`	If any part of the operand lies outside the effective address space from 0 to FFFFH.
`#NM`	If TS in CR0 is set.
`#XM`	If an unmasked SIMD floating-point exception and OSXMMEXCPT in CR4 is 1.

Virtual-8086 Mode Exceptions

Same exceptions as in Real Address Mode.

`#PF(fault-code)`	For a page fault.
`#PF(fault-code)`	For a page fault.

Instruction	Latency	Throughput	Execution Unit
`CPUID`	0F3n/0F2n/069n	0F3n/0F2n/069n	0F2n
`ADDSD xmm, xmm`	5/4/3	2/2/1	FP_ADD