Specifications

Intel
®
64 and IA-32 Architectures Software Developer’s Manual Documentation Changes 171
Documentation Changes
F3 REX.W 6F REP OUTS DX,
r/m32
A Valid N.E. Output RCX default size
from [RSI] to port DX.
F3 AC REP LODS AL A Valid Valid Load (E)CX bytes from
DS:[(E)SI] to AL.
F3 REX.W AC REP LODS AL A Valid N.E. Load RCX bytes from [RSI]
to AL.
F3 AD REP LODS AX A Valid Valid Load (E)CX words from
DS:[(E)SI] to AX.
F3 AD REP LODS EAX A Valid Valid Load (E)CX doublewords
from DS:[(E)SI] to EAX.
F3 REX.W AD REP LODS RAX A Valid N.E. Load RCX quadwords from
[RSI] to RAX.
F3 AA REP STOS m8 A Valid Valid Fill (E)CX bytes at ES:[(E)DI]
with AL.
F3 REX.W AA REP STOS m8 A Valid N.E. Fill RCX bytes at [RDI] with
AL.
F3 AB REP STOS m16 A Valid Valid Fill (E)CX words at ES:[(E)DI]
with AX.
F3 AB REP STOS m32 A Valid Valid Fill (E)CX doublewords at
ES:[(E)DI] with EAX.
F3 REX.W AB REP STOS m64 A Valid N.E. Fill RCX quadwords at [RDI]
with RAX.
F3 A6 REPE CMPS m8,
m8
A Valid Valid Find nonmatching bytes in
ES:[(E)DI] and DS:[(E)SI].
F3 REX.W A6 REPE CMPS m8,
m8
A Valid N.E. Find non-matching bytes in
[RDI] and [RSI].
F3 A7 REPE CMPS m16,
m16
A Valid Valid Find nonmatching words in
ES:[(E)DI] and DS:[(E)SI].
F3 A7 REPE CMPS m32,
m32
A Valid Valid Find nonmatching
doublewords in ES:[(E)DI]
and DS:[(E)SI].
F3 REX.W A7 REPE CMPS m64,
m64
A Valid N.E. Find non-matching
quadwords in [RDI] and
[RSI].
F3 AE REPE SCAS m8 A Valid Valid Find non-AL byte starting at
ES:[(E)DI].
F3 REX.W AE REPE SCAS m8 A Valid N.E. Find non-AL byte starting at
[RDI].
F3 AF REPE SCAS m16 A Valid Valid Find non-AX word starting
at ES:[(E)DI].
F3 AF REPE SCAS m32 A Valid Valid Find non-EAX doubleword
starting at ES:[(E)DI].
F3 REX.W AF REPE SCAS m64 A Valid N.E. Find non-RAX quadword
starting at [RDI].
Opcode Instruction Op/
En
64-Bit
Mode
Compat/
Leg Mode
Description