x86 Instruction Set Reference

# ADDSS

# Add Scalar Single-Precision Floating-Point Values

Opcode Mnemonic Description
F3 0F 58 /r ADDSS xmm1, xmm2/m32 Add the low single-precision floating-point value from xmm2/m32 to xmm1.

# Description

Adds the low single-precision floating-point values from the source operand (second operand) and the destination operand (first operand), and stores the single-precision floating-point result in the destination operand. The source operand can be an XMM register or a 32-bit memory location. The destination operand is an XMM register. The three high-order doublewords of the destination operand remain unchanged.

# Operation

Destination[0..31] = Destination[0..31] + Source[0..31];
//Destination[32..127] remain unchanged
1
2
3

# 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 SSE 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
ADDSS xmm, xmm 5/4/3 2/2/1 FP_ADD

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