resistance was useless, wilson is now part of the collective (as intel)

This commit is contained in:
Torsten Ruger 2014-05-08 15:09:56 +03:00
parent f7f0eee31a
commit f0ad11bf8c
15 changed files with 5255 additions and 0 deletions

88
lib/intel/address.rb Normal file
View File

@ -0,0 +1,88 @@
require 'intel/operand'
module Intel
##
# Address is a memory address in one of the following example forms:
#
# eax, ebx + ecx, eax + 5, 23545, edx + eax + 2312
class Address < Operand
attr_accessor :id, :index
attr_reader :offset
attr_writer :isAssemblerOffset # FIX
def initialize isAssemblerOffset = nil, bits = nil, id = nil
super(nil,bits)
self.isAssemblerOffset = isAssemblerOffset
self.id = id
self.index = self.offset = nil
end
def bits
super || self.machine.bits
end
def offset= obj
if obj.is_a?(Register) then
@offset = 0
self.index = obj
else
@offset = obj
end
end
def + o # TODO: this seems totally and completely wrong
if o.is_a?(Register) then
self.index = o
else
self.offset = o
end
self
end
def address?
true
end
def offset?
@isAssemblerOffset.nil? ? id.nil? : @isAssemblerOffset
end
def push_mod_rm_on spareRegister, stream
if id.nil? then
stream << (0b00000101 + (spareRegister.id << 3))
return stream.push_D(offset)
end
modrm = case offset
when 0 then
0b00000000
when 1..255 then
0b01000000
else
0b10000000
end
if index.nil? then
modrm += (spareRegister.id << 3)
else
stream << (0b00000100 + (spareRegister.id << 3))
modrm += (index.id << 3)
end
stream << modrm + id
return self if offset == 0
return stream.push_B(offset) if offset < 256
stream.push_D offset
end
def m
self
end
end
end

10
lib/intel/all.rb Normal file
View File

@ -0,0 +1,10 @@
# -*- coding: utf-8 -*-
require_relative 'versions'
require_relative 'immediate'
require_relative 'command'
require_relative 'assembler'
require_relative 'machine_code_x86'
require_relative 'core_extensions'
require_relative 'label'
require_relative "register"

147
lib/intel/assembler.rb Normal file
View File

@ -0,0 +1,147 @@
require 'intel/register'
require 'intel/address'
module Intel
##
# Assembler parses the NASM documentation and creates Command
# objects for it
class Assembler
attr_accessor :commands , :raw_commands
def self.nasm_fixes
# TODO: extend parser to split /[,:]/ and remove some of these
'
CALL imm,imm16 ; o16 9A iw iw [8086]
CALL imm,imm32 ; o32 9A id iw [386]
CALLFAR mem16 ; o16 FF /3 [8086]
CALLFAR mem32 ; o32 FF /3 [386]
Jcc imm ; 0F 80+cc rw/rd [386]
JMP imm,imm16 ; o16 EA iw iw [8086]
JMP imm,imm32 ; o32 EA id iw [386]
JMP imm16 ; E9 rw/rd [8086]
JMP imm32 ; E9 rw/rd [8086]
JMP imm8 ; EB rb [8086]
JMPFAR mem16 ; o16 FF /5 [8086]
JMPFAR mem32 ; o32 FF /5 [386]
FADDTO fpureg ; DC C0+r [8086,FPU]
FDIVTO fpureg ; DC F8+r [8086,FPU]
FDIVRTO fpureg ; DC F0+r [8086,FPU]
FMULTO fpureg ; DC C8+r [8086,FPU]
FSUBTO fpureg ; DC E8+r [8086,FPU]
FSUBRTO fpureg ; DC E0+r [8086,FPU]
CMP r/m16,imm8 ; o16 83 /7 ib [8086]
CMP r/m32,imm8 ; o32 83 /7 ib [386]
SAR r/m16,1 ; o16 D1 /7 [8086]
SAR r/m32,1 ; o32 D1 /7 [386]
'
end
def self.nasm
File.read(__FILE__.sub(".rb",".txt"))
end
@@default = nil
def self.default
@@default ||= self.new.parse
end
def self.commands
self.default.commands
end
def initialize
self.commands = []
self.raw_commands = []
end
def expand_parameters command
command.parameters.each_with_index do |parameter, index|
if String === parameter && parameter =~ /^r\/m(\d+)/ then
bits = $1.to_i
newCommand = command.dup
commands << newCommand
case bits
when 8, 16, 32 then
command.parameters[index] = MemoryRegister.new bits
newCommand.parameters[index] = Address.new false, bits
when 64 then
command.parameters[index] = MMXRegister.new nil,nil,bits
newCommand.parameters[index] = Address.new false, bits
end
end
end
end
def add_conditional_commands prototype
prototype.opcode = prototype.opcode[0..-3]
self.conditionals.each do |conditional, value|
command = prototype.dup
command.opcode += conditional
command.opcodes.each_with_index do |op, index|
command.opcodes[index] = ($1.hex+value).to_s(16) if op =~ /(.*)\+cc$/
end
self.add_command command
end
end
def process_line line # TODO: remove
return if line.empty?
return unless line =~ /^[A-Z].+;.*\[/
self.parse_command line
end
def add_raw_command raw
@raw_commands << raw
end
def add_command command
return self.add_conditional_commands(command) if command.opcode =~ /cc$/i
self.commands << command
self.expand_parameters command
end
def conditionals
@conditionals ||= {
'O' => 0, 'NO' => 1, 'B' => 2, 'C' => 2, 'NAE' => 2,
'AE' => 3, 'NB' => 3, 'NC' => 3, 'E' => 4, 'Z' => 4,
'NE' => 5, 'NZ' => 5, 'BE' => 6, 'NA' => 6, 'A' => 7,
'NBE' => 7, 'S' => 8, 'NS' => 9, 'P' => 10, 'PE' => 10,
'NP' => 11, 'PO' => 11, 'L' => 12, 'NGE' => 12, 'GE' => 13,
'NL' => 13, 'LE' => 14, 'NG' => 14, 'G' => 15, 'NLE' => 15,
}
end
def parse_command line
if line =~ /^(\w+)\s+([^;]*)\s+;\s+([^\[]+)\s+\[([\w,]+)\]/ then
name, params, ops, procs = $1, $2, $3, $4
command = Command.new(name, ops.split , procs.split(/,/) )
command.initialize_parameters params.strip
self.add_raw_command command
else
raise "unparsed: #{line}"
end
end
def parse
(self.class.nasm + self.class.nasm_fixes).each_line do |line|
self.process_line line.strip.sub(/^# /, '')
end
@raw_commands.each do |command|
add_command command
end
self
end
end
end

3500
lib/intel/assembler.txt Normal file
View File

@ -0,0 +1,3500 @@
# -*- coding: utf-8 -*-
# The Netwide Assembler: NASM
# Previous Chapter <nasmdo10.html> | Contents <nasmdoc0.html> | Index
# <nasmdoci.html>
# Appendix A: Intel x86 Instruction Reference
# This appendix provides a complete list of the machine instructions which
# NASM will assemble, and a short description of the function of each one.
# It is not intended to be exhaustive documentation on the fine details of
# the instructions' function, such as which exceptions they can trigger:
# for such documentation, you should go to Intel's Web site,
# |http://www.intel.com/|.
# Instead, this appendix is intended primarily to provide documentation on
# the way the instructions may be used within NASM. For example, looking
# up |LOOP| will tell you that NASM allows |CX| or |ECX| to be specified
# as an optional second argument to the |LOOP| instruction, to enforce
# which of the two possible counter registers should be used if the
# default is not the one desired.
# The instructions are not quite listed in alphabetical order, since
# groups of instructions with similar functions are lumped together in the
# same entry. Most of them don't move very far from their alphabetic
# position because of this.
# A.1 Key to Operand Specifications
# The instruction descriptions in this appendix specify their operands
# using the following notation:
# * Registers: |reg8| denotes an 8-bit general purpose register,
# |reg16| denotes a 16-bit general purpose register, and |reg32| a
# 32-bit one. |fpureg| denotes one of the eight FPU stack registers,
# |mmxreg| denotes one of the eight 64-bit MMX registers, and
# |segreg| denotes a segment register. In addition, some registers
# (such as |AL|, |DX| or |ECX|) may be specified explicitly.
# * Immediate operands: |imm| denotes a generic immediate operand.
# |imm8|, |imm16| and |imm32| are used when the operand is intended
# to be a specific size. For some of these instructions, NASM needs
# an explicit specifier: for example, |ADD ESP,16| could be
# interpreted as either |ADD r/m32,imm32| or |ADD r/m32,imm8|. NASM
# chooses the former by default, and so you must specify |ADD
# ESP,BYTE 16| for the latter.
# * Memory references: |mem| denotes a generic memory reference;
# |mem8|, |mem16|, |mem32|, |mem64| and |mem80| are used when the
# operand needs to be a specific size. Again, a specifier is needed
# in some cases: |DEC [address]| is ambiguous and will be rejected
# by NASM. You must specify |DEC BYTE [address]|, |DEC WORD
# [address]| or |DEC DWORD [address]| instead.
# * Restricted memory references: one form of the |MOV| instruction
# allows a memory address to be specified /without/ allowing the
# normal range of register combinations and effective address
# processing. This is denoted by |memoffs8|, |memoffs16| and
# |memoffs32|.
# * Register or memory choices: many instructions can accept either a
# register /or/ a memory reference as an operand. |r/m8| is a
# shorthand for |reg8/mem8|; similarly |r/m16| and |r/m32|. |r/m64|
# is MMX-related, and is a shorthand for |mmxreg/mem64|.
# A.2 Key to Opcode Descriptions
# This appendix also provides the opcodes which NASM will generate for
# each form of each instruction. The opcodes are listed in the following way:
# * A hex number, such as |3F|, indicates a fixed byte containing that
# number.
# * A hex number followed by |+r|, such as |C8+r|, indicates that one
# of the operands to the instruction is a register, and the
# `register value' of that register should be added to the hex
# number to produce the generated byte. For example, EDX has
# register value 2, so the code |C8+r|, when the register operand is
# EDX, generates the hex byte |CA|. Register values for specific
# registers are given in section A.2.1 <#section-A.2.1>.
# * A hex number followed by |+cc|, such as |40+cc|, indicates that
# the instruction name has a condition code suffix, and the numeric
# representation of the condition code should be added to the hex
# number to produce the generated byte. For example, the code
# |40+cc|, when the instruction contains the |NE| condition,
# generates the hex byte |45|. Condition codes and their numeric
# representations are given in section A.2.2 <#section-A.2.2>.
# * A slash followed by a digit, such as |/2|, indicates that one of
# the operands to the instruction is a memory address or register
# (denoted |mem| or |r/m|, with an optional size). This is to be
# encoded as an effective address, with a ModR/M byte, an optional
# SIB byte, and an optional displacement, and the spare (register)
# field of the ModR/M byte should be the digit given (which will be
# from 0 to 7, so it fits in three bits). The encoding of effective
# addresses is given in section A.2.3 <#section-A.2.3>.
# * The code |/r| combines the above two: it indicates that one of the
# operands is a memory address or |r/m|, and another is a register,
# and that an effective address should be generated with the spare
# (register) field in the ModR/M byte being equal to the `register
# value' of the register operand. The encoding of effective
# addresses is given in section A.2.3 <#section-A.2.3>; register
# values are given in section A.2.1 <#section-A.2.1>.
# * The codes |ib|, |iw| and |id| indicate that one of the operands to
# the instruction is an immediate value, and that this is to be
# encoded as a byte, little-endian word or little-endian doubleword
# respectively.
# * The codes |rb|, |rw| and |rd| indicate that one of the operands to
# the instruction is an immediate value, and that the /difference/
# between this value and the address of the end of the instruction
# is to be encoded as a byte, word or doubleword respectively. Where
# the form |rw/rd| appears, it indicates that either |rw| or |rd|
# should be used according to whether assembly is being performed in
# |BITS 16| or |BITS 32| state respectively.
# * The codes |ow| and |od| indicate that one of the operands to the
# instruction is a reference to the contents of a memory address
# specified as an immediate value: this encoding is used in some
# forms of the |MOV| instruction in place of the standard
# effective-address mechanism. The displacement is encoded as a word
# or doubleword. Again, |ow/od| denotes that |ow| or |od| should be
# chosen according to the |BITS| setting.
# * The codes |o16| and |o32| indicate that the given form of the
# instruction should be assembled with operand size 16 or 32 bits.
# In other words, |o16| indicates a |66| prefix in |BITS 32| state,
# but generates no code in |BITS 16| state; and |o32| indicates a
# |66| prefix in |BITS 16| state but generates nothing in |BITS 32|.
# * The codes |a16| and |a32|, similarly to |o16| and |o32|, indicate
# the address size of the given form of the instruction. Where this
# does not match the |BITS| setting, a |67| prefix is required.
# A.2.1 Register Values
# Where an instruction requires a register value, it is already implicit
# in the encoding of the rest of the instruction what type of register is
# intended: an 8-bit general-purpose register, a segment register, a debug
# register, an MMX register, or whatever. Therefore there is no problem
# with registers of different types sharing an encoding value.
# The encodings for the various classes of register are:
# * 8-bit general registers: |AL| is 0, |CL| is 1, |DL| is 2, |BL| is
# 3, |AH| is 4, |CH| is 5, |DH| is 6, and |BH| is 7.
# * 16-bit general registers: |AX| is 0, |CX| is 1, |DX| is 2, |BX| is
# 3, |SP| is 4, |BP| is 5, |SI| is 6, and |DI| is 7.
# * 32-bit general registers: |EAX| is 0, |ECX| is 1, |EDX| is 2,
# |EBX| is 3, |ESP| is 4, |EBP| is 5, |ESI| is 6, and |EDI| is 7.
# * Segment registers: |ES| is 0, |CS| is 1, |SS| is 2, |DS| is 3,
# |FS| is 4, and |GS| is 5.
# * {Floating-point registers}: |ST0| is 0, |ST1| is 1, |ST2| is 2,
# |ST3| is 3, |ST4| is 4, |ST5| is 5, |ST6| is 6, and |ST7| is 7.
# * 64-bit MMX registers: |MM0| is 0, |MM1| is 1, |MM2| is 2, |MM3| is
# 3, |MM4| is 4, |MM5| is 5, |MM6| is 6, and |MM7| is 7.
# * Control registers: |CR0| is 0, |CR2| is 2, |CR3| is 3, and |CR4|
# is 4.
# * Debug registers: |DR0| is 0, |DR1| is 1, |DR2| is 2, |DR3| is 3,
# |DR6| is 6, and |DR7| is 7.
# * Test registers: |TR3| is 3, |TR4| is 4, |TR5| is 5, |TR6| is 6,
# and |TR7| is 7.
# (Note that wherever a register name contains a number, that number is
# also the register value for that register.)
# A.2.2 Condition Codes
# The available condition codes are given here, along with their numeric
# representations as part of opcodes. Many of these condition codes have
# synonyms, so several will be listed at a time.
# In the following descriptions, the word `either', when applied to two
# possible trigger conditions, is used to mean `either or both'. If
# `either but not both' is meant, the phrase `exactly one of' is used.
# * |O| is 0 (trigger if the overflow flag is set); |NO| is 1.
# * |B|, |C| and |NAE| are 2 (trigger if the carry flag is set); |AE|,
# |NB| and |NC| are 3.
# * |E| and |Z| are 4 (trigger if the zero flag is set); |NE| and |NZ|
# are 5.
# * |BE| and |NA| are 6 (trigger if either of the carry or zero flags
# is set); |A| and |NBE| are 7.
# * |S| is 8 (trigger if the sign flag is set); |NS| is 9.
# * |P| and |PE| are 10 (trigger if the parity flag is set); |NP| and
# |PO| are 11.
# * |L| and |NGE| are 12 (trigger if exactly one of the sign and
# overflow flags is set); |GE| and |NL| are 13.
# * |LE| and |NG| are 14 (trigger if either the zero flag is set, or
# exactly one of the sign and overflow flags is set); |G| and |NLE|
# are 15.
# Note that in all cases, the sense of a condition code may be reversed by
# changing the low bit of the numeric representation.
# A.2.3 Effective Address Encoding: ModR/M and SIB
# An effective address is encoded in up to three parts: a ModR/M byte, an
# optional SIB byte, and an optional byte, word or doubleword displacement
# field.
# The ModR/M byte consists of three fields: the |mod| field, ranging from
# 0 to 3, in the upper two bits of the byte, the |r/m| field, ranging from
# 0 to 7, in the lower three bits, and the spare (register) field in the
# middle (bit 3 to bit 5). The spare field is not relevant to the
# effective address being encoded, and either contains an extension to the
# instruction opcode or the register value of another operand.
# The ModR/M system can be used to encode a direct register reference
# rather than a memory access. This is always done by setting the |mod|
# field to 3 and the |r/m| field to the register value of the register in
# question (it must be a general-purpose register, and the size of the
# register must already be implicit in the encoding of the rest of the
# instruction). In this case, the SIB byte and displacement field are both
# absent.
# In 16-bit addressing mode (either |BITS 16| with no |67| prefix, or
# |BITS 32| with a |67| prefix), the SIB byte is never used. The general
# rules for |mod| and |r/m| (there is an exception, given below) are:
# * The |mod| field gives the length of the displacement field: 0
# means no displacement, 1 means one byte, and 2 means two bytes.
# * The |r/m| field encodes the combination of registers to be added
# to the displacement to give the accessed address: 0 means |BX+SI|,
# 1 means |BX+DI|, 2 means |BP+SI|, 3 means |BP+DI|, 4 means |SI|
# only, 5 means |DI| only, 6 means |BP| only, and 7 means |BX| only.
# However, there is a special case:
# * If |mod| is 0 and |r/m| is 6, the effective address encoded is not
# |[BP]| as the above rules would suggest, but instead |[disp16]|:
# the displacement field is present and is two bytes long, and no
# registers are added to the displacement.
# Therefore the effective address |[BP]| cannot be encoded as efficiently
# as |[BX]|; so if you code |[BP]| in a program, NASM adds a notional
# 8-bit zero displacement, and sets |mod| to 1, |r/m| to 6, and the
# one-byte displacement field to 0.
# In 32-bit addressing mode (either |BITS 16| with a |67| prefix, or |BITS
# 32| with no |67| prefix) the general rules (again, there are exceptions)
# for |mod| and |r/m| are:
# * The |mod| field gives the length of the displacement field: 0
# means no displacement, 1 means one byte, and 2 means four bytes.
# * If only one register is to be added to the displacement, and it is
# not |ESP|, the |r/m| field gives its register value, and the SIB
# byte is absent. If the |r/m| field is 4 (which would encode
# |ESP|), the SIB byte is present and gives the combination and
# scaling of registers to be added to the displacement.
# If the SIB byte is present, it describes the combination of registers
# (an optional base register, and an optional index register scaled by
# multiplication by 1, 2, 4 or 8) to be added to the displacement. The SIB
# byte is divided into the |scale| field, in the top two bits, the |index|
# field in the next three, and the |base| field in the bottom three. The
# general rules are:
# * The |base| field encodes the register value of the base register.
# * The |index| field encodes the register value of the index
# register, unless it is 4, in which case no index register is used
# (so |ESP| cannot be used as an index register).
# * The |scale| field encodes the multiplier by which the index
# register is scaled before adding it to the base and displacement:
# 0 encodes a multiplier of 1, 1 encodes 2, 2 encodes 4 and 3
# encodes 8.
# The exceptions to the 32-bit encoding rules are:
# * If |mod| is 0 and |r/m| is 5, the effective address encoded is not
# |[EBP]| as the above rules would suggest, but instead |[disp32]|:
# the displacement field is present and is four bytes long, and no
# registers are added to the displacement.
# * If |mod| is 0, |r/m| is 4 (meaning the SIB byte is present) and
# |base| is 4, the effective address encoded is not |[EBP+index]| as
# the above rules would suggest, but instead |[disp32+index]|: the
# displacement field is present and is four bytes long, and there is
# no base register (but the index register is still processed in the
# normal way).
# A.3 Key to Instruction Flags
# Given along with each instruction in this appendix is a set of flags,
# denoting the type of the instruction. The types are as follows:
# * |8086|, |186|, |286|, |386|, |486|, |PENT| and |P6| denote the
# lowest processor type that supports the instruction. Most
# instructions run on all processors above the given type; those
# that do not are documented. The Pentium II contains no additional
# instructions beyond the P6 (Pentium Pro); from the point of view
# of its instruction set, it can be thought of as a P6 with MMX
# capability.
# * |CYRIX| indicates that the instruction is specific to Cyrix
# processors, for example the extra MMX instructions in the Cyrix
# extended MMX instruction set.
# * |FPU| indicates that the instruction is a floating-point one, and
# will only run on machines with a coprocessor (automatically
# including 486DX, Pentium and above).
# * |MMX| indicates that the instruction is an MMX one, and will run
# on MMX-capable Pentium processors and the Pentium II.
# * |PRIV| indicates that the instruction is a protected-mode
# management instruction. Many of these may only be used in
# protected mode, or only at privilege level zero.
# * |UNDOC| indicates that the instruction is an undocumented one, and
# not part of the official Intel Architecture; it may or may not be
# supported on any given machine.
# A.4 |AAA|, |AAS|, |AAM|, |AAD|: ASCII Adjustments
# AAA ; 37 [8086]
# AAS ; 3F [8086]
# AAD ; D5 0A [8086]
# AAD imm ; D5 ib [8086]
# AAM ; D4 0A [8086]
# AAM imm ; D4 ib [8086]
# These instructions are used in conjunction with the add, subtract,
# multiply and divide instructions to perform binary-coded decimal
# arithmetic in /unpacked/ (one BCD digit per byte - easy to translate to
# and from ASCII, hence the instruction names) form. There are also packed
# BCD instructions |DAA| and |DAS|: see section A.23 <#section-A.23>.
# |AAA| should be used after a one-byte |ADD| instruction whose
# destination was the |AL| register: by means of examining the value in
# the low nibble of |AL| and also the auxiliary carry flag |AF|, it
# determines whether the addition has overflowed, and adjusts it (and sets
# the carry flag) if so. You can add long BCD strings together by doing
# |ADD|/|AAA| on the low digits, then doing |ADC|/|AAA| on each subsequent
# digit.
# |AAS| works similarly to |AAA|, but is for use after |SUB| instructions
# rather than |ADD|.
# |AAM| is for use after you have multiplied two decimal digits together
# and left the result in |AL|: it divides |AL| by ten and stores the
# quotient in |AH|, leaving the remainder in |AL|. The divisor 10 can be
# changed by specifying an operand to the instruction: a particularly
# handy use of this is |AAM 16|, causing the two nibbles in |AL| to be
# separated into |AH| and |AL|.
# |AAD| performs the inverse operation to |AAM|: it multiplies |AH| by
# ten, adds it to |AL|, and sets |AH| to zero. Again, the multiplier 10
# can be changed.
# A.5 |ADC|: Add with Carry
# ADC r/m8,reg8 ; 10 /r [8086]
# ADC r/m16,reg16 ; o16 11 /r [8086]
# ADC r/m32,reg32 ; o32 11 /r [386]
# ADC reg8,r/m8 ; 12 /r [8086]
# ADC reg16,r/m16 ; o16 13 /r [8086]
# ADC reg32,r/m32 ; o32 13 /r [386]
# ADC r/m8,imm8 ; 80 /2 ib [8086]
# ADC r/m16,imm16 ; o16 81 /2 iw [8086]
# ADC r/m32,imm32 ; o32 81 /2 id [386]
# ADC r/m16,imm8 ; o16 83 /2 ib [8086]
# ADC r/m32,imm8 ; o32 83 /2 ib [386]
# ADC AL,imm8 ; 14 ib [8086]
# ADC AX,imm16 ; o16 15 iw [8086]
# ADC EAX,imm32 ; o32 15 id [386]
# |ADC| performs integer addition: it adds its two operands together, plus
# the value of the carry flag, and leaves the result in its destination
# (first) operand. The flags are set according to the result of the
# operation: in particular, the carry flag is affected and can be used by
# a subsequent |ADC| instruction.
# In the forms with an 8-bit immediate second operand and a longer first
# operand, the second operand is considered to be signed, and is
# sign-extended to the length of the first operand. In these cases, the
# |BYTE| qualifier is necessary to force NASM to generate this form of the
# instruction.
# To add two numbers without also adding the contents of the carry flag,
# use |ADD| (section A.6 <#section-A.6>).
# A.6 |ADD|: Add Integers
# ADD r/m8,reg8 ; 00 /r [8086]
# ADD r/m16,reg16 ; o16 01 /r [8086]
# ADD r/m32,reg32 ; o32 01 /r [386]
# ADD reg8,r/m8 ; 02 /r [8086]
# ADD reg16,r/m16 ; o16 03 /r [8086]
# ADD reg32,r/m32 ; o32 03 /r [386]
# ADD r/m8,imm8 ; 80 /0 ib [8086]
# ADD r/m16,imm16 ; o16 81 /0 iw [8086]
# ADD r/m32,imm32 ; o32 81 /0 id [386]
# ADD r/m16,imm8 ; o16 83 /0 ib [8086]
# ADD r/m32,imm8 ; o32 83 /0 ib [386]
# ADD AL,imm8 ; 04 ib [8086]
# ADD AX,imm16 ; o16 05 iw [8086]
# ADD EAX,imm32 ; o32 05 id [386]
# |ADD| performs integer addition: it adds its two operands together, and
# leaves the result in its destination (first) operand. The flags are set
# according to the result of the operation: in particular, the carry flag
# is affected and can be used by a subsequent |ADC| instruction (section
# A.5 <#section-A.5>).
# In the forms with an 8-bit immediate second operand and a longer first
# operand, the second operand is considered to be signed, and is
# sign-extended to the length of the first operand. In these cases, the
# |BYTE| qualifier is necessary to force NASM to generate this form of the
# instruction.
# A.7 |AND|: Bitwise AND
# AND r/m8,reg8 ; 20 /r [8086]
# AND r/m16,reg16 ; o16 21 /r [8086]
# AND r/m32,reg32 ; o32 21 /r [386]
# AND reg8,r/m8 ; 22 /r [8086]
# AND reg16,r/m16 ; o16 23 /r [8086]
# AND reg32,r/m32 ; o32 23 /r [386]
# AND r/m8,imm8 ; 80 /4 ib [8086]
# AND r/m16,imm16 ; o16 81 /4 iw [8086]
# AND r/m32,imm32 ; o32 81 /4 id [386]
# AND r/m16,imm8 ; o16 83 /4 ib [8086]
# AND r/m32,imm8 ; o32 83 /4 ib [386]
# AND AL,imm8 ; 24 ib [8086]
# AND AX,imm16 ; o16 25 iw [8086]
# AND EAX,imm32 ; o32 25 id [386]
# |AND| performs a bitwise AND operation between its two operands (i.e.
# each bit of the result is 1 if and only if the corresponding bits of the
# two inputs were both 1), and stores the result in the destination
# (first) operand.
# In the forms with an 8-bit immediate second operand and a longer first
# operand, the second operand is considered to be signed, and is
# sign-extended to the length of the first operand. In these cases, the
# |BYTE| qualifier is necessary to force NASM to generate this form of the
# instruction.
# The MMX instruction |PAND| (see section A.116 <#section-A.116>) performs
# the same operation on the 64-bit MMX registers.
# A.8 |ARPL|: Adjust RPL Field of Selector
# ARPL r/m16,reg16 ; 63 /r [286,PRIV]
# |ARPL| expects its two word operands to be segment selectors. It adjusts
# the RPL (requested privilege level - stored in the bottom two bits of
# the selector) field of the destination (first) operand to ensure that it
# is no less (i.e. no more privileged than) the RPL field of the source
# operand. The zero flag is set if and only if a change had to be made.
# A.9 |BOUND|: Check Array Index against Bounds
# BOUND reg16,mem ; o16 62 /r [186]
# BOUND reg32,mem ; o32 62 /r [386]
# |BOUND| expects its second operand to point to an area of memory
# containing two signed values of the same size as its first operand (i.e.
# two words for the 16-bit form; two doublewords for the 32-bit form). It
# performs two signed comparisons: if the value in the register passed as
# its first operand is less than the first of the in-memory values, or is
# greater than or equal to the second, it throws a BR exception.
# Otherwise, it does nothing.
# A.10 |BSF|, |BSR|: Bit Scan
# BSF reg16,r/m16 ; o16 0F BC /r [386]
# BSF reg32,r/m32 ; o32 0F BC /r [386]
# BSR reg16,r/m16 ; o16 0F BD /r [386]
# BSR reg32,r/m32 ; o32 0F BD /r [386]
# |BSF| searches for a set bit in its source (second) operand, starting
# from the bottom, and if it finds one, stores the index in its
# destination (first) operand. If no set bit is found, the contents of the
# destination operand are undefined.
# |BSR| performs the same function, but searches from the top instead, so
# it finds the most significant set bit.
# Bit indices are from 0 (least significant) to 15 or 31 (most significant).
# A.11 |BSWAP|: Byte Swap
# BSWAP reg32 ; o32 0F C8+r [486]
# |BSWAP| swaps the order of the four bytes of a 32-bit register: bits 0-7
# exchange places with bits 24-31, and bits 8-15 swap with bits 16-23.
# There is no explicit 16-bit equivalent: to byte-swap |AX|, |BX|, |CX| or
# |DX|, |XCHG| can be used.
# A.12 |BT|, |BTC|, |BTR|, |BTS|: Bit Test
# BT r/m16,reg16 ; o16 0F A3 /r [386]
# BT r/m32,reg32 ; o32 0F A3 /r [386]
# BT r/m16,imm8 ; o16 0F BA /4 ib [386]
# BT r/m32,imm8 ; o32 0F BA /4 ib [386]
# BTC r/m16,reg16 ; o16 0F BB /r [386]
# BTC r/m32,reg32 ; o32 0F BB /r [386]
# BTC r/m16,imm8 ; o16 0F BA /7 ib [386]
# BTC r/m32,imm8 ; o32 0F BA /7 ib [386]
# BTR r/m16,reg16 ; o16 0F B3 /r [386]
# BTR r/m32,reg32 ; o32 0F B3 /r [386]
# BTR r/m16,imm8 ; o16 0F BA /6 ib [386]
# BTR r/m32,imm8 ; o32 0F BA /6 ib [386]
# BTS r/m16,reg16 ; o16 0F AB /r [386]
# BTS r/m32,reg32 ; o32 0F AB /r [386]
# BTS r/m16,imm ; o16 0F BA /5 ib [386]
# BTS r/m32,imm ; o32 0F BA /5 ib [386]
# These instructions all test one bit of their first operand, whose index
# is given by the second operand, and store the value of that bit into the
# carry flag. Bit indices are from 0 (least significant) to 15 or 31 (most
# significant).
# In addition to storing the original value of the bit into the carry
# flag, |BTR| also resets (clears) the bit in the operand itself. |BTS|
# sets the bit, and |BTC| complements the bit. |BT| does not modify its
# operands.
# The bit offset should be no greater than the size of the operand.
# A.13 |CALL|: Call Subroutine
# CALL imm ; E8 rw/rd [8086]
# CALL imm:imm16 ; o16 9A iw iw [8086]
# CALL imm:imm32 ; o32 9A id iw [386]
# CALL FAR mem16 ; o16 FF /3 [8086]
# CALL FAR mem32 ; o32 FF /3 [386]
# CALL r/m16 ; o16 FF /2 [8086]
# CALL r/m32 ; o32 FF /2 [386]
# |CALL| calls a subroutine, by means of pushing the current instruction
# pointer (|IP|) and optionally |CS| as well on the stack, and then
# jumping to a given address.
# |CS| is pushed as well as |IP| if and only if the call is a far call,
# i.e. a destination segment address is specified in the instruction. The
# forms involving two colon-separated arguments are far calls; so are the
# |CALL FAR mem| forms.
# You can choose between the two immediate far call forms (|CALL imm:imm|)
# by the use of the |WORD| and |DWORD| keywords: |CALL WORD
# 0x1234:0x5678|) or |CALL DWORD 0x1234:0x56789abc|.
# The |CALL FAR mem| forms execute a far call by loading the destination
# address out of memory. The address loaded consists of 16 or 32 bits of
# offset (depending on the operand size), and 16 bits of segment. The
# operand size may be overridden using |CALL WORD FAR mem| or |CALL DWORD
# FAR mem|.
# The |CALL r/m| forms execute a near call (within the same segment),
# loading the destination address out of memory or out of a register. The
# keyword |NEAR| may be specified, for clarity, in these forms, but is not
# necessary. Again, operand size can be overridden using |CALL WORD mem|
# or |CALL DWORD mem|.
# As a convenience, NASM does not require you to call a far procedure
# symbol by coding the cumbersome |CALL SEG routine:routine|, but instead
# allows the easier synonym |CALL FAR routine|.
# The |CALL r/m| forms given above are near calls; NASM will accept the
# |NEAR| keyword (e.g. |CALL NEAR [address]|), even though it is not
# strictly necessary.
# A.14 |CBW|, |CWD|, |CDQ|, |CWDE|: Sign Extensions
# CBW ; o16 98 [8086]
# CWD ; o16 99 [8086]
# CDQ ; o32 99 [386]
# CWDE ; o32 98 [386]
# All these instructions sign-extend a short value into a longer one, by
# replicating the top bit of the original value to fill the extended one.
# |CBW| extends |AL| into |AX| by repeating the top bit of |AL| in every
# bit of |AH|. |CWD| extends |AX| into |DX:AX| by repeating the top bit of
# |AX| throughout |DX|. |CWDE| extends |AX| into |EAX|, and |CDQ| extends
# |EAX| into |EDX:EAX|.
# A.15 |CLC|, |CLD|, |CLI|, |CLTS|: Clear Flags
# CLC ; F8 [8086]
# CLD ; FC [8086]
# CLI ; FA [8086]
# CLTS ; 0F 06 [286,PRIV]
# These instructions clear various flags. |CLC| clears the carry flag;
# |CLD| clears the direction flag; |CLI| clears the interrupt flag (thus
# disabling interrupts); and |CLTS| clears the task-switched (|TS|) flag
# in |CR0|.
# To set the carry, direction, or interrupt flags, use the |STC|, |STD|
# and |STI| instructions (section A.156 <#section-A.156>). To invert the
# carry flag, use |CMC| (section A.16 <#section-A.16>).
# A.16 |CMC|: Complement Carry Flag
# CMC ; F5 [8086]
# |CMC| changes the value of the carry flag: if it was 0, it sets it to 1,
# and vice versa.
# A.17 |CMOVcc|: Conditional Move
# CMOVcc reg16,r/m16 ; o16 0F 40+cc /r [P6]
# CMOVcc reg32,r/m32 ; o32 0F 40+cc /r [P6]
# |CMOV| moves its source (second) operand into its destination (first)
# operand if the given condition code is satisfied; otherwise it does
# nothing.
# For a list of condition codes, see section A.2.2 <#section-A.2.2>.
# Although the |CMOV| instructions are flagged |P6| above, they may not be
# supported by all Pentium Pro processors; the |CPUID| instruction
# (section A.22 <#section-A.22>) will return a bit which indicates whether
# conditional moves are supported.
# A.18 |CMP|: Compare Integers
# CMP r/m8,reg8 ; 38 /r [8086]
# CMP r/m16,reg16 ; o16 39 /r [8086]
# CMP r/m32,reg32 ; o32 39 /r [386]
# CMP reg8,r/m8 ; 3A /r [8086]
# CMP reg16,r/m16 ; o16 3B /r [8086]
# CMP reg32,r/m32 ; o32 3B /r [386]
# CMP r/m8,imm8 ; 80 /0 ib [8086]
# CMP r/m16,imm16 ; o16 81 /0 iw [8086]
# CMP r/m32,imm32 ; o32 81 /0 id [386]
# DEADCMP r/m16,imm8 ; o16 83 /0 ib [8086]
# DEADCMP r/m32,imm8 ; o32 83 /0 ib [386]
# CMP AL,imm8 ; 3C ib [8086]
# CMP AX,imm16 ; o16 3D iw [8086]
# CMP EAX,imm32 ; o32 3D id [386]
# |CMP| performs a `mental' subtraction of its second operand from its
# first operand, and affects the flags as if the subtraction had taken
# place, but does not store the result of the subtraction anywhere.
# In the forms with an 8-bit immediate second operand and a longer first
# operand, the second operand is considered to be signed, and is
# sign-extended to the length of the first operand. In these cases, the
# |BYTE| qualifier is necessary to force NASM to generate this form of the
# instruction.
# A.19 |CMPSB|, |CMPSW|, |CMPSD|: Compare Strings
# CMPSB ; A6 [8086]
# CMPSW ; o16 A7 [8086]
# CMPSD ; o32 A7 [386]
# |CMPSB| compares the byte at |[DS:SI]| or |[DS:ESI]| with the byte at
# |[ES:DI]| or |[ES:EDI]|, and sets the flags accordingly. It then
# increments or decrements (depending on the direction flag: increments if
# the flag is clear, decrements if it is set) |SI| and |DI| (or |ESI| and
# |EDI|).
# The registers used are |SI| and |DI| if the address size is 16 bits, and
# |ESI| and |EDI| if it is 32 bits. If you need to use an address size not
# equal to the current |BITS| setting, you can use an explicit |a16| or
# |a32| prefix.
# The segment register used to load from |[SI]| or |[ESI]| can be
# overridden by using a segment register name as a prefix (for example,
# |es cmpsb|). The use of |ES| for the load from |[DI]| or |[EDI]| cannot
# be overridden.
# |CMPSW| and |CMPSD| work in the same way, but they compare a word or a
# doubleword instead of a byte, and increment or decrement the addressing
# registers by 2 or 4 instead of 1.
# The |REPE| and |REPNE| prefixes (equivalently, |REPZ| and |REPNZ|) may
# be used to repeat the instruction up to |CX| (or |ECX| - again, the
# address size chooses which) times until the first unequal or equal byte
# is found.
# A.20 |CMPXCHG|, |CMPXCHG486|: Compare and Exchange
# CMPXCHG r/m8,reg8 ; 0F B0 /r [PENT]
# CMPXCHG r/m16,reg16 ; o16 0F B1 /r [PENT]
# CMPXCHG r/m32,reg32 ; o32 0F B1 /r [PENT]
# CMPXCHG486 r/m8,reg8 ; 0F A6 /r [486,UNDOC]
# CMPXCHG486 r/m16,reg16 ; o16 0F A7 /r [486,UNDOC]
# CMPXCHG486 r/m32,reg32 ; o32 0F A7 /r [486,UNDOC]
# These two instructions perform exactly the same operation; however,
# apparently some (not all) 486 processors support it under a non-standard
# opcode, so NASM provides the undocumented |CMPXCHG486| form to generate
# the non-standard opcode.
# |CMPXCHG| compares its destination (first) operand to the value in |AL|,
# |AX| or |EAX| (depending on the size of the instruction). If they are
# equal, it copies its source (second) operand into the destination and
# sets the zero flag. Otherwise, it clears the zero flag and leaves the
# destination alone.
# |CMPXCHG| is intended to be used for atomic operations in multitasking
# or multiprocessor environments. To safely update a value in shared
# memory, for example, you might load the value into |EAX|, load the
# updated value into |EBX|, and then execute the instruction |lock cmpxchg
# [value],ebx|. If |value| has not changed since being loaded, it is
# updated with your desired new value, and the zero flag is set to let you
# know it has worked. (The |LOCK| prefix prevents another processor doing
# anything in the middle of this operation: it guarantees atomicity.)
# However, if another processor has modified the value in between your
# load and your attempted store, the store does not happen, and you are
# notified of the failure by a cleared zero flag, so you can go round and
# try again.
# A.21 |CMPXCHG8B|: Compare and Exchange Eight Bytes
# CMPXCHG8B mem ; 0F C7 /1 [PENT]
# This is a larger and more unwieldy version of |CMPXCHG|: it compares the
# 64-bit (eight-byte) value stored at |[mem]| with the value in |EDX:EAX|.
# If they are equal, it sets the zero flag and stores |ECX:EBX| into the
# memory area. If they are unequal, it clears the zero flag and leaves the
# memory area untouched.
# A.22 |CPUID|: Get CPU Identification Code
# CPUID ; 0F A2 [PENT]
# |CPUID| returns various information about the processor it is being
# executed on. It fills the four registers |EAX|, |EBX|, |ECX| and |EDX|
# with information, which varies depending on the input contents of |EAX|.
# |CPUID| also acts as a barrier to serialise instruction execution:
# executing the |CPUID| instruction guarantees that all the effects
# (memory modification, flag modification, register modification) of
# previous instructions have been completed before the next instruction
# gets fetched.
# The information returned is as follows:
# * If |EAX| is zero on input, |EAX| on output holds the maximum
# acceptable input value of |EAX|, and |EBX:EDX:ECX| contain the
# string |"GenuineIntel"| (or not, if you have a clone processor).
# That is to say, |EBX| contains |"Genu"| (in NASM's own sense of
# character constants, described in section 3.4.2
# <nasmdoc3.html#section-3.4.2>), |EDX| contains |"ineI"| and |ECX|
# contains |"ntel"|.
# * If |EAX| is one on input, |EAX| on output contains version
# information about the processor, and |EDX| contains a set of
# feature flags, showing the presence and absence of various
# features. For example, bit 8 is set if the |CMPXCHG8B| instruction
# (section A.21 <#section-A.21>) is supported, bit 15 is set if the
# conditional move instructions (section A.17 <#section-A.17> and
# section A.34 <#section-A.34>) are supported, and bit 23 is set if
# MMX instructions are supported.
# * If |EAX| is two on input, |EAX|, |EBX|, |ECX| and |EDX| all
# contain information about caches and TLBs (Translation Lookahead
# Buffers).
# For more information on the data returned from |CPUID|, see the
# documentation on Intel's web site.
# A.23 |DAA|, |DAS|: Decimal Adjustments
# DAA ; 27 [8086]
# DAS ; 2F [8086]
# These instructions are used in conjunction with the add and subtract
# instructions to perform binary-coded decimal arithmetic in /packed/ (one
# BCD digit per nibble) form. For the unpacked equivalents, see section
# A.4 <#section-A.4>.
# |DAA| should be used after a one-byte |ADD| instruction whose
# destination was the |AL| register: by means of examining the value in
# the |AL| and also the auxiliary carry flag |AF|, it determines whether
# either digit of the addition has overflowed, and adjusts it (and sets
# the carry and auxiliary-carry flags) if so. You can add long BCD strings
# together by doing |ADD|/|DAA| on the low two digits, then doing
# |ADC|/|DAA| on each subsequent pair of digits.
# |DAS| works similarly to |DAA|, but is for use after |SUB| instructions
# rather than |ADD|.
# A.24 |DEC|: Decrement Integer
# DEC reg16 ; o16 48+r [8086]
# DEC reg32 ; o32 48+r [386]
# DEC r/m8 ; FE /1 [8086]
# DEC r/m16 ; o16 FF /1 [8086]
# DEC r/m32 ; o32 FF /1 [386]
# |DEC| subtracts 1 from its operand. It does /not/ affect the carry flag:
# to affect the carry flag, use |SUB something,1| (see section A.159
# <#section-A.159>). See also |INC| (section A.79 <#section-A.79>).
# A.25 |DIV|: Unsigned Integer Divide
# DIV r/m8 ; F6 /6 [8086]
# DIV r/m16 ; o16 F7 /6 [8086]
# DIV r/m32 ; o32 F7 /6 [386]
# |DIV| performs unsigned integer division. The explicit operand provided
# is the divisor; the dividend and destination operands are implicit, in
# the following way:
# * For |DIV r/m8|, |AX| is divided by the given operand; the quotient
# is stored in |AL| and the remainder in |AH|.
# * For |DIV r/m16|, |DX:AX| is divided by the given operand; the
# quotient is stored in |AX| and the remainder in |DX|.
# * For |DIV r/m32|, |EDX:EAX| is divided by the given operand; the
# quotient is stored in |EAX| and the remainder in |EDX|.
# Signed integer division is performed by the |IDIV| instruction: see
# section A.76 <#section-A.76>.
# A.26 |EMMS|: Empty MMX State
# MMS ; 0F 77 [PENT,MMX]
# |EMMS| sets the FPU tag word (marking which floating-point registers are
# available) to all ones, meaning all registers are available for the FPU
# to use. It should be used after executing MMX instructions and before
# executing any subsequent floating-point operations.
# A.27 |ENTER|: Create Stack Frame
# ENTER imm,imm ; C8 iw ib [186]
# |ENTER| constructs a stack frame for a high-level language procedure
# call. The first operand (the |iw| in the opcode definition above refers
# to the first operand) gives the amount of stack space to allocate for
# local variables; the second (the |ib| above) gives the nesting level of
# the procedure (for languages like Pascal, with nested procedures).
# The function of |ENTER|, with a nesting level of zero, is equivalent to
# PUSH EBP ; or PUSH BP in 16 bits
# MOV EBP,ESP ; or MOV BP,SP in 16 bits
# SUB ESP,operand1 ; or SUB SP,operand1 in 16 bits
# This creates a stack frame with the procedure parameters accessible
# upwards from |EBP|, and local variables accessible downwards from |EBP|.
# With a nesting level of one, the stack frame created is 4 (or 2) bytes
# bigger, and the value of the final frame pointer |EBP| is accessible in
# memory at |[EBP-4]|.
# This allows |ENTER|, when called with a nesting level of two, to look at
# the stack frame described by the /previous/ value of |EBP|, find the
# frame pointer at offset -4 from that, and push it along with its new
# frame pointer, so that when a level-two procedure is called from within
# a level-one procedure, |[EBP-4]| holds the frame pointer of the most
# recent level-one procedure call and |[EBP-8]| holds that of the most
# recent level-two call. And so on, for nesting levels up to 31.
# Stack frames created by |ENTER| can be destroyed by the |LEAVE|
# instruction: see section A.94 <#section-A.94>.
# A.28 |F2XM1|: Calculate 2**X-1
# F2XM1 ; D9 F0 [8086,FPU]
# |F2XM1| raises 2 to the power of |ST0|, subtracts one, and stores the
# result back into |ST0|. The initial contents of |ST0| must be a number
# in the range -1 to +1.
# A.29 |FABS|: Floating-Point Absolute Value
# FABS ; D9 E1 [8086,FPU]
# |FABS| computes the absolute value of |ST0|, storing the result back in
# |ST0|.
# A.30 |FADD|, |FADDP|: Floating-Point Addition
# FADD mem32 ; D8 /0 [8086,FPU]
# FADD mem64 ; DC /0 [8086,FPU]
# FADD fpureg ; D8 C0+r [8086,FPU]
# FADD ST0,fpureg ; D8 C0+r [8086,FPU]
# FADD TO fpureg ; DC C0+r [8086,FPU]
# FADD fpureg,ST0 ; DC C0+r [8086,FPU]
# FADDP fpureg ; DE C0+r [8086,FPU]
# FADDP fpureg,ST0 ; DE C0+r [8086,FPU]
# |FADD|, given one operand, adds the operand to |ST0| and stores the
# result back in |ST0|. If the operand has the |TO| modifier, the result
# is stored in the register given rather than in |ST0|.
# |FADDP| performs the same function as |FADD TO|, but pops the register
# stack after storing the result.
# The given two-operand forms are synonyms for the one-operand forms.
# A.31 |FBLD|, |FBSTP|: BCD Floating-Point Load and Store
# FBLD mem80 ; DF /4 [8086,FPU]
# FBSTP mem80 ; DF /6 [8086,FPU]
# |FBLD| loads an 80-bit (ten-byte) packed binary-coded decimal number
# from the given memory address, converts it to a real, and pushes it on
# the register stack. |FBSTP| stores the value of |ST0|, in packed BCD, at
# the given address and then pops the register stack.
# A.32 |FCHS|: Floating-Point Change Sign
# FCHS ; D9 E0 [8086,FPU]
# |FCHS| negates the number in |ST0|: negative numbers become positive,
# and vice versa.
# A.33 |FCLEX|, {FNCLEX}: Clear Floating-Point Exceptions
# FCLEX ; 9B DB E2 [8086,FPU]
# FNCLEX ; DB E2 [8086,FPU]
# |FCLEX| clears any floating-point exceptions which may be pending.
# |FNCLEX| does the same thing but doesn't wait for previous
# floating-point operations (including the /handling/ of pending
# exceptions) to finish first.
# A.34 |FCMOVcc|: Floating-Point Conditional Move
# FCMOVB fpureg ; DA C0+r [P6,FPU]
# FCMOVB ST0,fpureg ; DA C0+r [P6,FPU]
# FCMOVBE fpureg ; DA D0+r [P6,FPU]
# FCMOVBE ST0,fpureg ; DA D0+r [P6,FPU]
# FCMOVE fpureg ; DA C8+r [P6,FPU]
# FCMOVE ST0,fpureg ; DA C8+r [P6,FPU]
# FCMOVNB fpureg ; DB C0+r [P6,FPU]
# FCMOVNB ST0,fpureg ; DB C0+r [P6,FPU]
# FCMOVNBE fpureg ; DB D0+r [P6,FPU]
# FCMOVNBE ST0,fpureg ; DB D0+r [P6,FPU]
# FCMOVNE fpureg ; DB C8+r [P6,FPU]
# FCMOVNE ST0,fpureg ; DB C8+r [P6,FPU]
# FCMOVNU fpureg ; DB D8+r [P6,FPU]
# FCMOVNU ST0,fpureg ; DB D8+r [P6,FPU]
# FCMOVU fpureg ; DA D8+r [P6,FPU]
# FCMOVU ST0,fpureg ; DA D8+r [P6,FPU]
# The |FCMOV| instructions perform conditional move operations: each of
# them moves the contents of the given register into |ST0| if its
# condition is satisfied, and does nothing if not.
# The conditions are not the same as the standard condition codes used
# with conditional jump instructions. The conditions |B|, |BE|, |NB|,
# |NBE|, |E| and |NE| are exactly as normal, but none of the other
# standard ones are supported. Instead, the condition |U| and its
# counterpart |NU| are provided; the |U| condition is satisfied if the
# last two floating-point numbers compared were /unordered/, i.e. they
# were not equal but neither one could be said to be greater than the
# other, for example if they were NaNs. (The flag state which signals this
# is the setting of the parity flag: so the |U| condition is notionally
# equivalent to |PE|, and |NU| is equivalent to |PO|.)
# The |FCMOV| conditions test the main processor's status flags, not the
# FPU status flags, so using |FCMOV| directly after |FCOM| will not work.
# Instead, you should either use |FCOMI| which writes directly to the main
# CPU flags word, or use |FSTSW| to extract the FPU flags.
# Although the |FCMOV| instructions are flagged |P6| above, they may not
# be supported by all Pentium Pro processors; the |CPUID| instruction
# (section A.22 <#section-A.22>) will return a bit which indicates whether
# conditional moves are supported.
# A.35 |FCOM|, |FCOMP|, |FCOMPP|, |FCOMI|, |FCOMIP|: Floating-Point
# Compare
# FCOM mem32 ; D8 /2 [8086,FPU]
# FCOM mem64 ; DC /2 [8086,FPU]
# FCOM fpureg ; D8 D0+r [8086,FPU]
# FCOM ST0,fpureg ; D8 D0+r [8086,FPU]
# FCOMP mem32 ; D8 /3 [8086,FPU]
# FCOMP mem64 ; DC /3 [8086,FPU]
# FCOMP fpureg ; D8 D8+r [8086,FPU]
# FCOMP ST0,fpureg ; D8 D8+r [8086,FPU]
# FCOMPP ; DE D9 [8086,FPU]
# FCOMI fpureg ; DB F0+r [P6,FPU]
# FCOMI ST0,fpureg ; DB F0+r [P6,FPU]
# FCOMIP fpureg ; DF F0+r [P6,FPU]
# FCOMIP ST0,fpureg ; DF F0+r [P6,FPU]
# |FCOM| compares |ST0| with the given operand, and sets the FPU flags
# accordingly. |ST0| is treated as the left-hand side of the comparison,
# so that the carry flag is set (for a `less-than' result) if |ST0| is
# less than the given operand.
# |FCOMP| does the same as |FCOM|, but pops the register stack afterwards.
# |FCOMPP| compares |ST0| with |ST1| and then pops the register stack twice.
# |FCOMI| and |FCOMIP| work like the corresponding forms of |FCOM| and
# |FCOMP|, but write their results directly to the CPU flags register
# rather than the FPU status word, so they can be immediately followed by
# conditional jump or conditional move instructions.
# The |FCOM| instructions differ from the |FUCOM| instructions (section
# A.69 <#section-A.69>) only in the way they handle quiet NaNs: |FUCOM|
# will handle them silently and set the condition code flags to an
# `unordered' result, whereas |FCOM| will generate an exception.
# A.36 |FCOS|: Cosine
# FCOS ; D9 FF [386,FPU]
# |FCOS| computes the cosine of |ST0| (in radians), and stores the result
# in |ST0|. See also |FSINCOS| (section A.61 <#section-A.61>).
# A.37 |FDECSTP|: Decrement Floating-Point Stack Pointer
# FDECSTP ; D9 F6 [8086,FPU]
# |FDECSTP| decrements the `top' field in the floating-point status word.
# This has the effect of rotating the FPU register stack by one, as if the
# contents of |ST7| had been pushed on the stack. See also |FINCSTP|
# (section A.46 <#section-A.46>).
# A.38 |FxDISI|, |FxENI|: Disable and Enable Floating-Point Interrupts
# FDISI ; 9B DB E1 [8086,FPU]
# FNDISI ; DB E1 [8086,FPU]
# FENI ; 9B DB E0 [8086,FPU]
# FNENI ; DB E0 [8086,FPU]
# |FDISI| and |FENI| disable and enable floating-point interrupts. These
# instructions are only meaningful on original 8087 processors: the 287
# and above treat them as no-operation instructions.
# |FNDISI| and |FNENI| do the same thing as |FDISI| and |FENI|
# respectively, but without waiting for the floating-point processor to
# finish what it was doing first.
# A.39 |FDIV|, |FDIVP|, |FDIVR|, |FDIVRP|: Floating-Point Division
# FDIV mem32 ; D8 /6 [8086,FPU]
# FDIV mem64 ; DC /6 [8086,FPU]
# FDIV fpureg ; D8 F0+r [8086,FPU]
# FDIV ST0,fpureg ; D8 F0+r [8086,FPU]
# FDIV TO fpureg ; DC F8+r [8086,FPU]
# FDIV fpureg,ST0 ; DC F8+r [8086,FPU]
# FDIVR mem32 ; D8 /0 [8086,FPU]
# FDIVR mem64 ; DC /0 [8086,FPU]
# FDIVR fpureg ; D8 F8+r [8086,FPU]
# FDIVR ST0,fpureg ; D8 F8+r [8086,FPU]
# FDIVR TO fpureg ; DC F0+r [8086,FPU]
# FDIVR fpureg,ST0 ; DC F0+r [8086,FPU]
# FDIVP fpureg ; DE F8+r [8086,FPU]
# FDIVP fpureg,ST0 ; DE F8+r [8086,FPU]
# FDIVRP fpureg ; DE F0+r [8086,FPU]
# FDIVRP fpureg,ST0 ; DE F0+r [8086,FPU]
# |FDIV| divides |ST0| by the given operand and stores the result back in
# |ST0|, unless the |TO| qualifier is given, in which case it divides the
# given operand by |ST0| and stores the result in the operand.
# |FDIVR| does the same thing, but does the division the other way up: so
# if |TO| is not given, it divides the given operand by |ST0| and stores
# the result in |ST0|, whereas if |TO| is given it divides |ST0| by its
# operand and stores the result in the operand.
# |FDIVP| operates like |FDIV TO|, but pops the register stack once it has
# finished. |FDIVRP| operates like |FDIVR TO|, but pops the register stack
# once it has finished.
# A.40 |FFREE|: Flag Floating-Point Register as Unused
# FFREE fpureg ; DD C0+r [8086,FPU]
# |FFREE| marks the given register as being empty.
# A.41 |FIADD|: Floating-Point/Integer Addition
# FIADD mem16 ; DE /0 [8086,FPU]
# FIADD mem32 ; DA /0 [8086,FPU]
# |FIADD| adds the 16-bit or 32-bit integer stored in the given memory
# location to |ST0|, storing the result in |ST0|.
# A.42 |FICOM|, |FICOMP|: Floating-Point/Integer Compare
# FICOM mem16 ; DE /2 [8086,FPU]
# FICOM mem32 ; DA /2 [8086,FPU]
# FICOMP mem16 ; DE /3 [8086,FPU]
# FICOMP mem32 ; DA /3 [8086,FPU]
# |FICOM| compares |ST0| with the 16-bit or 32-bit integer stored in the
# given memory location, and sets the FPU flags accordingly. |FICOMP| does
# the same, but pops the register stack afterwards.
# A.43 |FIDIV|, |FIDIVR|: Floating-Point/Integer Division
# FIDIV mem16 ; DE /6 [8086,FPU]
# FIDIV mem32 ; DA /6 [8086,FPU]
# FIDIVR mem16 ; DE /0 [8086,FPU]
# FIDIVR mem32 ; DA /0 [8086,FPU]
# |FIDIV| divides |ST0| by the 16-bit or 32-bit integer stored in the
# given memory location, and stores the result in |ST0|. |FIDIVR| does the
# division the other way up: it divides the integer by |ST0|, but still
# stores the result in |ST0|.
# A.44 |FILD|, |FIST|, |FISTP|: Floating-Point/Integer Conversion
# FILD mem16 ; DF /0 [8086,FPU]
# FILD mem32 ; DB /0 [8086,FPU]
# FILD mem64 ; DF /5 [8086,FPU]
# FIST mem16 ; DF /2 [8086,FPU]
# FIST mem32 ; DB /2 [8086,FPU]
# FISTP mem16 ; DF /3 [8086,FPU]
# FISTP mem32 ; DB /3 [8086,FPU]
# FISTP mem64 ; DF /0 [8086,FPU]
# |FILD| loads an integer out of a memory location, converts it to a real,
# and pushes it on the FPU register stack. |FIST| converts |ST0| to an
# integer and stores that in memory; |FISTP| does the same as |FIST|, but
# pops the register stack afterwards.
# A.45 |FIMUL|: Floating-Point/Integer Multiplication
# FIMUL mem16 ; DE /1 [8086,FPU]
# FIMUL mem32 ; DA /1 [8086,FPU]
# |FIMUL| multiplies |ST0| by the 16-bit or 32-bit integer stored in the
# given memory location, and stores the result in |ST0|.
# A.46 |FINCSTP|: Increment Floating-Point Stack Pointer
# FINCSTP ; D9 F7 [8086,FPU]
# |FINCSTP| increments the `top' field in the floating-point status word.
# This has the effect of rotating the FPU register stack by one, as if the
# register stack had been popped; however, unlike the popping of the stack
# performed by many FPU instructions, it does not flag the new |ST7|
# (previously |ST0|) as empty. See also |FDECSTP| (section A.37
# <#section-A.37>).
# A.47 |FINIT|, |FNINIT|: Initialise Floating-Point Unit
# FINIT ; 9B DB E3 [8086,FPU]
# FNINIT ; DB E3 [8086,FPU]
# |FINIT| initialises the FPU to its default state. It flags all registers
# as empty, though it does not actually change their values. |FNINIT| does
# the same, without first waiting for pending exceptions to clear.
# A.48 |FISUB|: Floating-Point/Integer Subtraction
# FISUB mem16 ; DE /4 [8086,FPU]
# FISUB mem32 ; DA /4 [8086,FPU]
# FISUBR mem16 ; DE /5 [8086,FPU]
# FISUBR mem32 ; DA /5 [8086,FPU]
# |FISUB| subtracts the 16-bit or 32-bit integer stored in the given
# memory location from |ST0|, and stores the result in |ST0|. |FISUBR|
# does the subtraction the other way round, i.e. it subtracts |ST0| from
# the given integer, but still stores the result in |ST0|.
# A.49 |FLD|: Floating-Point Load
# FLD mem32 ; D9 /0 [8086,FPU]
# FLD mem64 ; DD /0 [8086,FPU]
# FLD mem80 ; DB /5 [8086,FPU]
# FLD fpureg ; D9 C0+r [8086,FPU]
# |FLD| loads a floating-point value out of the given register or memory
# location, and pushes it on the FPU register stack.
# A.50 |FLDxx|: Floating-Point Load Constants
# FLD1 ; D9 E8 [8086,FPU]
# FLDL2E ; D9 EA [8086,FPU]
# FLDL2T ; D9 E9 [8086,FPU]
# FLDLG2 ; D9 EC [8086,FPU]
# FLDLN2 ; D9 ED [8086,FPU]
# FLDPI ; D9 EB [8086,FPU]
# FLDZ ; D9 EE [8086,FPU]
# These instructions push specific standard constants on the FPU register
# stack. |FLD1| pushes the value 1; |FLDL2E| pushes the base-2 logarithm
# of e; |FLDL2T| pushes the base-2 log of 10; |FLDLG2| pushes the base-10
# log of 2; |FLDLN2| pushes the base-e log of 2; |FLDPI| pushes pi; and
# |FLDZ| pushes zero.
# A.51 |FLDCW|: Load Floating-Point Control Word
# FLDCW mem16 ; D9 /5 [8086,FPU]
# |FLDCW| loads a 16-bit value out of memory and stores it into the FPU
# control word (governing things like the rounding mode, the precision,
# and the exception masks). See also |FSTCW| (section A.64 <#section-A.64>).
# A.52 |FLDENV|: Load Floating-Point Environment
# FLDENV mem ; D9 /4 [8086,FPU]
# |FLDENV| loads the FPU operating environment (control word, status word,
# tag word, instruction pointer, data pointer and last opcode) from
# memory. The memory area is 14 or 28 bytes long, depending on the CPU
# mode at the time. See also |FSTENV| (section A.65 <#section-A.65>).
# A.53 |FMUL|, |FMULP|: Floating-Point Multiply
# FMUL mem32 ; D8 /1 [8086,FPU]
# FMUL mem64 ; DC /1 [8086,FPU]
# FMUL fpureg ; D8 C8+r [8086,FPU]
# FMUL ST0,fpureg ; D8 C8+r [8086,FPU]
# FMUL TO fpureg ; DC C8+r [8086,FPU]
# FMUL fpureg,ST0 ; DC C8+r [8086,FPU]
# FMULP fpureg ; DE C8+r [8086,FPU]
# FMULP fpureg,ST0 ; DE C8+r [8086,FPU]
# |FMUL| multiplies |ST0| by the given operand, and stores the result in
# |ST0|, unless the |TO| qualifier is used in which case it stores the
# result in the operand. |FMULP| performs the same operation as |FMUL TO|,
# and then pops the register stack.
# A.54 |FNOP|: Floating-Point No Operation
# FNOP ; D9 D0 [8086,FPU]
# |FNOP| does nothing.
# A.55 |FPATAN|, |FPTAN|: Arctangent and Tangent
# FPATAN ; D9 F3 [8086,FPU]
# FPTAN ; D9 F2 [8086,FPU]
# |FPATAN| computes the arctangent, in radians, of the result of dividing
# |ST1| by |ST0|, stores the result in |ST1|, and pops the register stack.
# It works like the C |atan2| function, in that changing the sign of both
# |ST0| and |ST1| changes the output value by pi (so it performs true
# rectangular-to-polar coordinate conversion, with |ST1| being the Y
# coordinate and |ST0| being the X coordinate, not merely an arctangent).
# |FPTAN| computes the tangent of the value in |ST0| (in radians), and
# stores the result back into |ST0|.
# A.56 |FPREM|, |FPREM1|: Floating-Point Partial Remainder
# FPREM ; D9 F8 [8086,FPU]
# FPREM1 ; D9 F5 [386,FPU]
# These instructions both produce the remainder obtained by dividing |ST0|
# by |ST1|. This is calculated, notionally, by dividing |ST0| by |ST1|,
# rounding the result to an integer, multiplying by |ST1| again, and
# computing the value which would need to be added back on to the result
# to get back to the original value in |ST0|.
# The two instructions differ in the way the notional round-to-integer
# operation is performed. |FPREM| does it by rounding towards zero, so
# that the remainder it returns always has the same sign as the original
# value in |ST0|; |FPREM1| does it by rounding to the nearest integer, so
# that the remainder always has at most half the magnitude of |ST1|.
# Both instructions calculate /partial/ remainders, meaning that they may
# not manage to provide the final result, but might leave intermediate
# results in |ST0| instead. If this happens, they will set the C2 flag in
# the FPU status word; therefore, to calculate a remainder, you should
# repeatedly execute |FPREM| or |FPREM1| until C2 becomes clear.
# A.57 |FRNDINT|: Floating-Point Round to Integer
# FRNDINT ; D9 FC [8086,FPU]
# |FRNDINT| rounds the contents of |ST0| to an integer, according to the
# current rounding mode set in the FPU control word, and stores the result
# back in |ST0|.
# A.58 |FSAVE|, |FRSTOR|: Save/Restore Floating-Point State
# FSAVE mem ; 9B DD /6 [8086,FPU]
# FNSAVE mem ; DD /6 [8086,FPU]
# FRSTOR mem ; DD /4 [8086,FPU]
# |FSAVE| saves the entire floating-point unit state, including all the
# information saved by |FSTENV| (section A.65 <#section-A.65>) plus the
# contents of all the registers, to a 94 or 108 byte area of memory
# (depending on the CPU mode). |FRSTOR| restores the floating-point state
# from the same area of memory.
# |FNSAVE| does the same as |FSAVE|, without first waiting for pending
# floating-point exceptions to clear.
# A.59 |FSCALE|: Scale Floating-Point Value by Power of Two
# FSCALE ; D9 FD [8086,FPU]
# |FSCALE| scales a number by a power of two: it rounds |ST1| towards zero
# to obtain an integer, then multiplies |ST0| by two to the power of that
# integer, and stores the result in |ST0|.
# A.60 |FSETPM|: Set Protected Mode
# FSETPM ; DB E4 [286,FPU]
# This instruction initalises protected mode on the 287 floating-point
# coprocessor. It is only meaningful on that processor: the 387 and above
# treat the instruction as a no-operation.
# A.61 |FSIN|, |FSINCOS|: Sine and Cosine
# FSIN ; D9 FE [386,FPU]
# FSINCOS ; D9 FB [386,FPU]
# |FSIN| calculates the sine of |ST0| (in radians) and stores the result
# in |ST0|. |FSINCOS| does the same, but then pushes the cosine of the
# same value on the register stack, so that the sine ends up in |ST1| and
# the cosine in |ST0|. |FSINCOS| is faster than executing |FSIN| and
# |FCOS| (see section A.36 <#section-A.36>) in succession.
# A.62 |FSQRT|: Floating-Point Square Root
# FSQRT ; D9 FA [8086,FPU]
# |FSQRT| calculates the square root of |ST0| and stores the result in |ST0|.
# A.63 |FST|, |FSTP|: Floating-Point Store
# FST mem32 ; D9 /2 [8086,FPU]
# FST mem64 ; DD /2 [8086,FPU]
# FST fpureg ; DD D0+r [8086,FPU]
# FSTP mem32 ; D9 /3 [8086,FPU]
# FSTP mem64 ; DD /3 [8086,FPU]
# FSTP mem80 ; DB /0 [8086,FPU]
# FSTP fpureg ; DD D8+r [8086,FPU]
# |FST| stores the value in |ST0| into the given memory location or other
# FPU register. |FSTP| does the same, but then pops the register stack.
# A.64 |FSTCW|: Store Floating-Point Control Word
# FSTCW mem16 ; 9B D9 /0 [8086,FPU]
# FNSTCW mem16 ; D9 /0 [8086,FPU]
# |FSTCW| stores the FPU control word (governing things like the rounding
# mode, the precision, and the exception masks) into a 2-byte memory area.
# See also |FLDCW| (section A.51 <#section-A.51>).
# |FNSTCW| does the same thing as |FSTCW|, without first waiting for
# pending floating-point exceptions to clear.
# A.65 |FSTENV|: Store Floating-Point Environment
# FSTENV mem ; 9B D9 /6 [8086,FPU]
# FNSTENV mem ; D9 /6 [8086,FPU]
# |FSTENV| stores the FPU operating environment (control word, status
# word, tag word, instruction pointer, data pointer and last opcode) into
# memory. The memory area is 14 or 28 bytes long, depending on the CPU
# mode at the time. See also |FLDENV| (section A.52 <#section-A.52>).
# |FNSTENV| does the same thing as |FSTENV|, without first waiting for
# pending floating-point exceptions to clear.
# A.66 |FSTSW|: Store Floating-Point Status Word
# FSTSW mem16 ; 9B DD /0 [8086,FPU]
# FSTSW AX ; 9B DF E0 [286,FPU]
# FNSTSW mem16 ; DD /0 [8086,FPU]
# FNSTSW AX ; DF E0 [286,FPU]
# |FSTSW| stores the FPU status word into |AX| or into a 2-byte memory area.
# |FNSTSW| does the same thing as |FSTSW|, without first waiting for
# pending floating-point exceptions to clear.
# A.67 |FSUB|, |FSUBP|, |FSUBR|, |FSUBRP|: Floating-Point Subtract
# FSUB mem32 ; D8 /4 [8086,FPU]
# FSUB mem64 ; DC /4 [8086,FPU]
# FSUB fpureg ; D8 E0+r [8086,FPU]
# FSUB ST0,fpureg ; D8 E0+r [8086,FPU]
# FSUB TO fpureg ; DC E8+r [8086,FPU]
# FSUB fpureg,ST0 ; DC E8+r [8086,FPU]
# FSUBR mem32 ; D8 /5 [8086,FPU]
# FSUBR mem64 ; DC /5 [8086,FPU]
# FSUBR fpureg ; D8 E8+r [8086,FPU]
# FSUBR ST0,fpureg ; D8 E8+r [8086,FPU]
# FSUBR TO fpureg ; DC E0+r [8086,FPU]
# FSUBR fpureg,ST0 ; DC E0+r [8086,FPU]
# FSUBP fpureg ; DE E8+r [8086,FPU]
# FSUBP fpureg,ST0 ; DE E8+r [8086,FPU]
# FSUBRP fpureg ; DE E0+r [8086,FPU]
# FSUBRP fpureg,ST0 ; DE E0+r [8086,FPU]
# |FSUB| subtracts the given operand from |ST0| and stores the result back
# in |ST0|, unless the |TO| qualifier is given, in which case it subtracts
# |ST0| from the given operand and stores the result in the operand.
# |FSUBR| does the same thing, but does the subtraction the other way up:
# so if |TO| is not given, it subtracts |ST0| from the given operand and
# stores the result in |ST0|, whereas if |TO| is given it subtracts its
# operand from |ST0| and stores the result in the operand.
# |FSUBP| operates like |FSUB TO|, but pops the register stack once it has
# finished. |FSUBRP| operates like |FSUBR TO|, but pops the register stack
# once it has finished.
# A.68 |FTST|: Test |ST0| Against Zero
# FTST ; D9 E4 [8086,FPU]
# |FTST| compares |ST0| with zero and sets the FPU flags accordingly.
# |ST0| is treated as the left-hand side of the comparison, so that a
# `less-than' result is generated if |ST0| is negative.
# A.69 |FUCOMxx|: Floating-Point Unordered Compare
# FUCOM fpureg ; DD E0+r [386,FPU]
# FUCOM ST0,fpureg ; DD E0+r [386,FPU]
# FUCOMP fpureg ; DD E8+r [386,FPU]
# FUCOMP ST0,fpureg ; DD E8+r [386,FPU]
# FUCOMPP ; DA E9 [386,FPU]
# FUCOMI fpureg ; DB E8+r [P6,FPU]
# FUCOMI ST0,fpureg ; DB E8+r [P6,FPU]
# FUCOMIP fpureg ; DF E8+r [P6,FPU]
# FUCOMIP ST0,fpureg ; DF E8+r [P6,FPU]
# |FUCOM| compares |ST0| with the given operand, and sets the FPU flags
# accordingly. |ST0| is treated as the left-hand side of the comparison,
# so that the carry flag is set (for a `less-than' result) if |ST0| is
# less than the given operand.
# |FUCOMP| does the same as |FUCOM|, but pops the register stack
# afterwards. |FUCOMPP| compares |ST0| with |ST1| and then pops the
# register stack twice.
# |FUCOMI| and |FUCOMIP| work like the corresponding forms of |FUCOM| and
# |FUCOMP|, but write their results directly to the CPU flags register
# rather than the FPU status word, so they can be immediately followed by
# conditional jump or conditional move instructions.
# The |FUCOM| instructions differ from the |FCOM| instructions (section
# A.35 <#section-A.35>) only in the way they handle quiet NaNs: |FUCOM|
# will handle them silently and set the condition code flags to an
# `unordered' result, whereas |FCOM| will generate an exception.
# A.70 |FXAM|: Examine Class of Value in |ST0|
# FXAM ; D9 E5 [8086,FPU]
# |FXAM| sets the FPU flags C3, C2 and C0 depending on the type of value
# stored in |ST0|: 000 (respectively) for an unsupported format, 001 for a
# NaN, 010 for a normal finite number, 011 for an infinity, 100 for a
# zero, 101 for an empty register, and 110 for a denormal. It also sets
# the C1 flag to the sign of the number.
# A.71 |FXCH|: Floating-Point Exchange
# FXCH ; D9 C9 [8086,FPU]
# FXCH fpureg ; D9 C8+r [8086,FPU]
# FXCH fpureg,ST0 ; D9 C8+r [8086,FPU]
# FXCH ST0,fpureg ; D9 C8+r [8086,FPU]
# |FXCH| exchanges |ST0| with a given FPU register. The no-operand form
# exchanges |ST0| with |ST1|.
# A.72 |FXTRACT|: Extract Exponent and Significand
# FXTRACT ; D9 F4 [8086,FPU]
# |FXTRACT| separates the number in |ST0| into its exponent and
# significand (mantissa), stores the exponent back into |ST0|, and then
# pushes the significand on the register stack (so that the significand
# ends up in |ST0|, and the exponent in |ST1|).
# A.73 |FYL2X|, |FYL2XP1|: Compute Y times Log2(X) or Log2(X+1)
# FYL2X ; D9 F1 [8086,FPU]
# FYL2XP1 ; D9 F9 [8086,FPU]
# |FYL2X| multiplies |ST1| by the base-2 logarithm of |ST0|, stores the
# result in |ST1|, and pops the register stack (so that the result ends up
# in |ST0|). |ST0| must be non-zero and positive.
# |FYL2XP1| works the same way, but replacing the base-2 log of |ST0| with
# that of |ST0| plus one. This time, |ST0| must have magnitude no greater
# than 1 minus half the square root of two.
# A.74 |HLT|: Halt Processor
# HLT ; F4 [8086]
# |HLT| puts the processor into a halted state, where it will perform no
# more operations until restarted by an interrupt or a reset.
# A.75 |IBTS|: Insert Bit String
# IBTS r/m16,reg16 ; o16 0F A7 /r [386,UNDOC]
# IBTS r/m32,reg32 ; o32 0F A7 /r [386,UNDOC]
# No clear documentation seems to be available for this instruction: the
# best I've been able to find reads `Takes a string of bits from the
# second operand and puts them in the first operand'. It is present only
# in early 386 processors, and conflicts with the opcodes for
# |CMPXCHG486|. NASM supports it only for completeness. Its counterpart is
# |XBTS| (see section A.167 <#section-A.167>).
# A.76 |IDIV|: Signed Integer Divide
# IDIV r/m8 ; F6 /7 [8086]
# IDIV r/m16 ; o16 F7 /7 [8086]
# IDIV r/m32 ; o32 F7 /7 [386]
# |IDIV| performs signed integer division. The explicit operand provided
# is the divisor; the dividend and destination operands are implicit, in
# the following way:
# * For |IDIV r/m8|, |AX| is divided by the given operand; the
# quotient is stored in |AL| and the remainder in |AH|.
# * For |IDIV r/m16|, |DX:AX| is divided by the given operand; the
# quotient is stored in |AX| and the remainder in |DX|.
# * For |IDIV r/m32|, |EDX:EAX| is divided by the given operand; the
# quotient is stored in |EAX| and the remainder in |EDX|.
# Unsigned integer division is performed by the |DIV| instruction: see
# section A.25 <#section-A.25>.
# A.77 |IMUL|: Signed Integer Multiply
# IMUL r/m8 ; F6 /5 [8086]
# IMUL r/m16 ; o16 F7 /5 [8086]
# IMUL r/m32 ; o32 F7 /5 [386]
# IMUL reg16,r/m16 ; o16 0F AF /r [386]
# IMUL reg32,r/m32 ; o32 0F AF /r [386]
# IMUL reg16,imm8 ; o16 6B /r ib [286]
# IMUL reg16,imm16 ; o16 69 /r iw [286]
# IMUL reg32,imm8 ; o32 6B /r ib [386]
# IMUL reg32,imm32 ; o32 69 /r id [386]
# IMUL reg16,r/m16,imm8 ; o16 6B /r ib [286]
# IMUL reg16,r/m16,imm16 ; o16 69 /r iw [286]
# IMUL reg32,r/m32,imm8 ; o32 6B /r ib [386]
# IMUL reg32,r/m32,imm32 ; o32 69 /r id [386]
# |IMUL| performs signed integer multiplication. For the single-operand
# form, the other operand and destination are implicit, in the following way:
# * For |IMUL r/m8|, |AL| is multiplied by the given operand; the
# product is stored in |AX|.
# * For |IMUL r/m16|, |AX| is multiplied by the given operand; the
# product is stored in |DX:AX|.
# * For |IMUL r/m32|, |EAX| is multiplied by the given operand; the
# product is stored in |EDX:EAX|.
# The two-operand form multiplies its two operands and stores the result
# in the destination (first) operand. The three-operand form multiplies
# its last two operands and stores the result in the first operand.
# The two-operand form is in fact a shorthand for the three-operand form,
# as can be seen by examining the opcode descriptions: in the two-operand
# form, the code |/r| takes both its register and |r/m| parts from the
# same operand (the first one).
# In the forms with an 8-bit immediate operand and another longer source
# operand, the immediate operand is considered to be signed, and is
# sign-extended to the length of the other source operand. In these cases,
# the |BYTE| qualifier is necessary to force NASM to generate this form of
# the instruction.
# Unsigned integer multiplication is performed by the |MUL| instruction:
# see section A.107 <#section-A.107>.
# A.78 |IN|: Input from I/O Port
# IN AL,imm8 ; E4 ib [8086]
# IN AX,imm8 ; o16 E5 ib [8086]
# IN EAX,imm8 ; o32 E5 ib [386]
# IN AL,DX ; EC [8086]
# IN AX,DX ; o16 ED [8086]
# IN EAX,DX ; o32 ED [386]
# |IN| reads a byte, word or doubleword from the specified I/O port, and
# stores it in the given destination register. The port number may be
# specified as an immediate value if it is between 0 and 255, and
# otherwise must be stored in |DX|. See also |OUT| (section A.111
# <#section-A.111>).
# A.79 |INC|: Increment Integer
# INC reg16 ; o16 40+r [8086]
# INC reg32 ; o32 40+r [386]
# INC r/m8 ; FE /0 [8086]
# INC r/m16 ; o16 FF /0 [8086]
# INC r/m32 ; o32 FF /0 [386]
# |INC| adds 1 to its operand. It does /not/ affect the carry flag: to
# affect the carry flag, use |ADD something,1| (see section A.6
# <#section-A.6>). See also |DEC| (section A.24 <#section-A.24>).
# A.80 |INSB|, |INSW|, |INSD|: Input String from I/O Port
# INSB ; 6C [186]
# INSW ; o16 6D [186]
# INSD ; o32 6D [386]
# |INSB| inputs a byte from the I/O port specified in |DX| and stores it
# at |[ES:DI]| or |[ES:EDI]|. It then increments or decrements (depending
# on the direction flag: increments if the flag is clear, decrements if it
# is set) |DI| or |EDI|.
# The register used is |DI| if the address size is 16 bits, and |EDI| if
# it is 32 bits. If you need to use an address size not equal to the
# current |BITS| setting, you can use an explicit |a16| or |a32| prefix.
# Segment override prefixes have no effect for this instruction: the use
# of |ES| for the load from |[DI]| or |[EDI]| cannot be overridden.
# |INSW| and |INSD| work in the same way, but they input a word or a
# doubleword instead of a byte, and increment or decrement the addressing
# register by 2 or 4 instead of 1.
# The |REP| prefix may be used to repeat the instruction |CX| (or |ECX| -
# again, the address size chooses which) times.
# See also |OUTSB|, |OUTSW| and |OUTSD| (section A.112 <#section-A.112>).
# A.81 |INT|: Software Interrupt
# INT imm8 ; CD ib [8086]
# |INT| causes a software interrupt through a specified vector number from
# 0 to 255.
# The code generated by the |INT| instruction is always two bytes long:
# although there are short forms for some |INT| instructions, NASM does
# not generate them when it sees the |INT| mnemonic. In order to generate
# single-byte breakpoint instructions, use the |INT3| or |INT1|
# instructions (see section A.82 <#section-A.82>) instead.
# A.82 |INT3|, |INT1|, |ICEBP|, |INT01|: Breakpoints
# INT1 ; F1 [P6]
# ICEBP ; F1 [P6]
# INT01 ; F1 [P6]
# INT3 ; CC [8086]
# |INT1| and |INT3| are short one-byte forms of the instructions |INT 1|
# and |INT 3| (see section A.81 <#section-A.81>). They perform a similar
# function to their longer counterparts, but take up less code space. They
# are used as breakpoints by debuggers.
# |INT1|, and its alternative synonyms |INT01| and |ICEBP|, is an
# instruction used by in-circuit emulators (ICEs). It is present, though
# not documented, on some processors down to the 286, but is only
# documented for the Pentium Pro. |INT3| is the instruction normally used
# as a breakpoint by debuggers.
# |INT3| is not precisely equivalent to |INT 3|: the short form, since it
# is designed to be used as a breakpoint, bypasses the normal IOPL checks
# in virtual-8086 mode, and also does not go through interrupt redirection.
# A.83 |INTO|: Interrupt if Overflow
# INTO ; CE [8086]
# |INTO| performs an |INT 4| software interrupt (see section A.81
# <#section-A.81>) if and only if the overflow flag is set.
# A.84 |INVD|: Invalidate Internal Caches
# INVD ; 0F 08 [486]
# |INVD| invalidates and empties the processor's internal caches, and
# causes the processor to instruct external caches to do the same. It does
# not write the contents of the caches back to memory first: any modified
# data held in the caches will be lost. To write the data back first, use
# |WBINVD| (section A.164 <#section-A.164>).
# A.85 |INVLPG|: Invalidate TLB Entry
# INVLPG mem ; 0F 01 /0 [486]
# |INVLPG| invalidates the translation lookahead buffer (TLB) entry
# associated with the supplied memory address.
# A.86 |IRET|, |IRETW|, |IRETD|: Return from Interrupt
# IRET ; CF [8086]
# IRETW ; o16 CF [8086]
# IRETD ; o32 CF [386]
# |IRET| returns from an interrupt (hardware or software) by means of
# popping |IP| (or |EIP|), |CS| and the flags off the stack and then
# continuing execution from the new |CS:IP|.
# |IRETW| pops |IP|, |CS| and the flags as 2 bytes each, taking 6 bytes
# off the stack in total. |IRETD| pops |EIP| as 4 bytes, pops a further 4
# bytes of which the top two are discarded and the bottom two go into
# |CS|, and pops the flags as 4 bytes as well, taking 12 bytes off the stack.
# |IRET| is a shorthand for either |IRETW| or |IRETD|, depending on the
# default |BITS| setting at the time.
# A.87 |JCXZ|, |JECXZ|: Jump if CX/ECX Zero
# JCXZ imm ; o16 E3 rb [8086]
# JECXZ imm ; o32 E3 rb [386]
# |JCXZ| performs a short jump (with maximum range 128 bytes) if and only
# if the contents of the |CX| register is 0. |JECXZ| does the same thing,
# but with |ECX|.
# A.88 |JMP|: Jump
# JMP imm ; E9 rw/rd [8086]
# JMP SHORT imm ; EB rb [8086]
# JMP imm:imm16 ; o16 EA iw iw [8086]
# JMP imm:imm32 ; o32 EA id iw [386]
# JMP FAR mem ; o16 FF /5 [8086]
# JMP FAR mem ; o32 FF /5 [386]
# JMP r/m16 ; o16 FF /4 [8086]
# JMP r/m32 ; o32 FF /4 [386]
# |JMP| jumps to a given address. The address may be specified as an
# absolute segment and offset, or as a relative jump within the current
# segment.
# |JMP SHORT imm| has a maximum range of 128 bytes, since the displacement
# is specified as only 8 bits, but takes up less code space. NASM does not
# choose when to generate |JMP SHORT| for you: you must explicitly code
# |SHORT| every time you want a short jump.
# You can choose between the two immediate far jump forms (|JMP imm:imm|)
# by the use of the |WORD| and |DWORD| keywords: |JMP WORD 0x1234:0x5678|)
# or |JMP DWORD 0x1234:0x56789abc|.
# The |JMP FAR mem| forms execute a far jump by loading the destination
# address out of memory. The address loaded consists of 16 or 32 bits of
# offset (depending on the operand size), and 16 bits of segment. The
# operand size may be overridden using |JMP WORD FAR mem| or |JMP DWORD
# FAR mem|.
# The |JMP r/m| forms execute a near jump (within the same segment),
# loading the destination address out of memory or out of a register. The
# keyword |NEAR| may be specified, for clarity, in these forms, but is not
# necessary. Again, operand size can be overridden using |JMP WORD mem| or
# |JMP DWORD mem|.
# As a convenience, NASM does not require you to jump to a far symbol by
# coding the cumbersome |JMP SEG routine:routine|, but instead allows the
# easier synonym |JMP FAR routine|.
# The |CALL r/m| forms given above are near calls; NASM will accept the
# |NEAR| keyword (e.g. |CALL NEAR [address]|), even though it is not
# strictly necessary.
# A.89 |Jcc|: Conditional Branch
# Jcc imm ; 70+cc rb [8086]
# Jcc NEAR imm ; 0F 80+cc rw/rd [386]
# The conditional jump instructions execute a near (same segment) jump if
# and only if their conditions are satisfied. For example, |JNZ| jumps
# only if the zero flag is not set.
# The ordinary form of the instructions has only a 128-byte range; the
# |NEAR| form is a 386 extension to the instruction set, and can span the
# full size of a segment. NASM will not override your choice of jump
# instruction: if you want |Jcc NEAR|, you have to use the |NEAR| keyword.
# The |SHORT| keyword is allowed on the first form of the instruction, for
# clarity, but is not necessary.
# A.90 |LAHF|: Load AH from Flags
# LAHF ; 9F [8086]
# |LAHF| sets the |AH| register according to the contents of the low byte
# of the flags word. See also |SAHF| (section A.145 <#section-A.145>).
# A.91 |LAR|: Load Access Rights
# LAR reg16,r/m16 ; o16 0F 02 /r [286,PRIV]
# LAR reg32,r/m32 ; o32 0F 02 /r [286,PRIV]
# |LAR| takes the segment selector specified by its source (second)
# operand, finds the corresponding segment descriptor in the GDT or LDT,
# and loads the access-rights byte of the descriptor into its destination
# (first) operand.
# A.92 |LDS|, |LES|, |LFS|, |LGS|, |LSS|: Load Far Pointer
# LDS reg16,mem ; o16 C5 /r [8086]
# LDS reg32,mem ; o32 C5 /r [8086]
# LES reg16,mem ; o16 C4 /r [8086]
# LES reg32,mem ; o32 C4 /r [8086]
# LFS reg16,mem ; o16 0F B4 /r [386]
# LFS reg32,mem ; o32 0F B4 /r [386]
# LGS reg16,mem ; o16 0F B5 /r [386]
# LGS reg32,mem ; o32 0F B5 /r [386]
# LSS reg16,mem ; o16 0F B2 /r [386]
# LSS reg32,mem ; o32 0F B2 /r [386]
# These instructions load an entire far pointer (16 or 32 bits of offset,
# plus 16 bits of segment) out of memory in one go. |LDS|, for example,
# loads 16 or 32 bits from the given memory address into the given
# register (depending on the size of the register), then loads the /next/
# 16 bits from memory into |DS|. |LES|, |LFS|, |LGS| and |LSS| work in the
# same way but use the other segment registers.
# A.93 |LEA|: Load Effective Address
# LEA reg16,mem ; o16 8D /r [8086]
# LEA reg32,mem ; o32 8D /r [8086]
# |LEA|, despite its syntax, does not access memory. It calculates the
# effective address specified by its second operand as if it were going to
# load or store data from it, but instead it stores the calculated address
# into the register specified by its first operand. This can be used to
# perform quite complex calculations (e.g. |LEA EAX,[EBX+ECX*4+100]|) in
# one instruction.
# |LEA|, despite being a purely arithmetic instruction which accesses no
# memory, still requires square brackets around its second operand, as if
# it were a memory reference.
# A.94 |LEAVE|: Destroy Stack Frame
# LEAVE ; C9 [186]
# |LEAVE| destroys a stack frame of the form created by the |ENTER|
# instruction (see section A.27 <#section-A.27>). It is functionally
# equivalent to |MOV ESP,EBP| followed by |POP EBP| (or |MOV SP,BP|
# followed by |POP BP| in 16-bit mode).
# A.95 |LGDT|, |LIDT|, |LLDT|: Load Descriptor Tables
# LGDT mem ; 0F 01 /2 [286,PRIV]
# LIDT mem ; 0F 01 /3 [286,PRIV]
# LLDT r/m16 ; 0F 00 /2 [286,PRIV]
# |LGDT| and |LIDT| both take a 6-byte memory area as an operand: they
# load a 32-bit linear address and a 16-bit size limit from that area (in
# the opposite order) into the GDTR (global descriptor table register) or
# IDTR (interrupt descriptor table register). These are the only
# instructions which directly use /linear/ addresses, rather than
# segment/offset pairs.
# |LLDT| takes a segment selector as an operand. The processor looks up
# that selector in the GDT and stores the limit and base address given
# there into the LDTR (local descriptor table register).
# See also |SGDT|, |SIDT| and |SLDT| (section A.151 <#section-A.151>).
# A.96 |LMSW|: Load/Store Machine Status Word
# LMSW r/m16 ; 0F 01 /6 [286,PRIV]
# |LMSW| loads the bottom four bits of the source operand into the bottom
# four bits of the |CR0| control register (or the Machine Status Word, on
# 286 processors). See also |SMSW| (section A.155 <#section-A.155>).
# A.97 |LOADALL|, |LOADALL286|: Load Processor State
# LOADALL ; 0F 07 [386,UNDOC]
# LOADALL286 ; 0F 05 [286,UNDOC]
# This instruction, in its two different-opcode forms, is apparently
# supported on most 286 processors, some 386 and possibly some 486. The
# opcode differs between the 286 and the 386.
# The function of the instruction is to load all information relating to
# the state of the processor out of a block of memory: on the 286, this
# block is located implicitly at absolute address |0x800|, and on the 386
# and 486 it is at |[ES:EDI]|.
# A.98 |LODSB|, |LODSW|, |LODSD|: Load from String
# LODSB ; AC [8086]
# LODSW ; o16 AD [8086]
# LODSD ; o32 AD [386]
# |LODSB| loads a byte from |[DS:SI]| or |[DS:ESI]| into |AL|. It then
# increments or decrements (depending on the direction flag: increments if
# the flag is clear, decrements if it is set) |SI| or |ESI|.
# The register used is |SI| if the address size is 16 bits, and |ESI| if
# it is 32 bits. If you need to use an address size not equal to the
# current |BITS| setting, you can use an explicit |a16| or |a32| prefix.
# The segment register used to load from |[SI]| or |[ESI]| can be
# overridden by using a segment register name as a prefix (for example,
# |es lodsb|).
# |LODSW| and |LODSD| work in the same way, but they load a word or a
# doubleword instead of a byte, and increment or decrement the addressing
# registers by 2 or 4 instead of 1.
# A.99 |LOOP|, |LOOPE|, |LOOPZ|, |LOOPNE|, |LOOPNZ|: Loop with Counter
# LOOP imm ; E2 rb [8086]
# LOOP imm,CX ; a16 E2 rb [8086]
# LOOP imm,ECX ; a32 E2 rb [386]
# LOOPE imm ; E1 rb [8086]
# LOOPE imm,CX ; a16 E1 rb [8086]
# LOOPE imm,ECX ; a32 E1 rb [386]
# LOOPZ imm ; E1 rb [8086]
# LOOPZ imm,CX ; a16 E1 rb [8086]
# LOOPZ imm,ECX ; a32 E1 rb [386]
# LOOPNE imm ; E0 rb [8086]
# LOOPNE imm,CX ; a16 E0 rb [8086]
# LOOPNE imm,ECX ; a32 E0 rb [386]
# LOOPNZ imm ; E0 rb [8086]
# LOOPNZ imm,CX ; a16 E0 rb [8086]
# LOOPNZ imm,ECX ; a32 E0 rb [386]
# |LOOP| decrements its counter register (either |CX| or |ECX| - if one is
# not specified explicitly, the |BITS| setting dictates which is used) by
# one, and if the counter does not become zero as a result of this
# operation, it jumps to the given label. The jump has a range of 128 bytes.
# |LOOPE| (or its synonym |LOOPZ|) adds the additional condition that it
# only jumps if the counter is nonzero /and/ the zero flag is set.
# Similarly, |LOOPNE| (and |LOOPNZ|) jumps only if the counter is nonzero
# and the zero flag is clear.
# A.100 |LSL|: Load Segment Limit
# LSL reg16,r/m16 ; o16 0F 03 /r [286,PRIV]
# LSL reg32,r/m32 ; o32 0F 03 /r [286,PRIV]
# |LSL| is given a segment selector in its source (second) operand; it
# computes the segment limit value by loading the segment limit field from
# the associated segment descriptor in the GDT or LDT. (This involves
# shifting left by 12 bits if the segment limit is page-granular, and not
# if it is byte-granular; so you end up with a byte limit in either case.)
# The segment limit obtained is then loaded into the destination (first)
# operand.
# A.101 |LTR|: Load Task Register
# LTR r/m16 ; 0F 00 /3 [286,PRIV]
# |LTR| looks up the segment base and limit in the GDT or LDT descriptor
# specified by the segment selector given as its operand, and loads them
# into the Task Register.
# A.102 |MOV|: Move Data
# MOV r/m8,reg8 ; 88 /r [8086]
# MOV r/m16,reg16 ; o16 89 /r [8086]
# MOV r/m32,reg32 ; o32 89 /r [386]
# MOV reg8,r/m8 ; 8A /r [8086]
# MOV reg16,r/m16 ; o16 8B /r [8086]
# MOV reg32,r/m32 ; o32 8B /r [386]
# MOV reg8,imm8 ; B0+r ib [8086]
# MOV reg16,imm16 ; o16 B8+r iw [8086]
# MOV reg32,imm32 ; o32 B8+r id [386]
# MOV r/m8,imm8 ; C6 /0 ib [8086]
# MOV r/m16,imm16 ; o16 C7 /0 iw [8086]
# MOV r/m32,imm32 ; o32 C7 /0 id [386]
# MOV AL,memoffs8 ; A0 ow/od [8086]
# MOV AX,memoffs16 ; o16 A1 ow/od [8086]
# MOV EAX,memoffs32 ; o32 A1 ow/od [386]
# MOV memoffs8,AL ; A2 ow/od [8086]
# MOV memoffs16,AX ; o16 A3 ow/od [8086]
# MOV memoffs32,EAX ; o32 A3 ow/od [386]
# MOV r/m16,segreg ; o16 8C /r [8086]
# MOV r/m32,segreg ; o32 8C /r [386]
# MOV segreg,r/m16 ; o16 8E /r [8086]
# MOV segreg,r/m32 ; o32 8E /r [386]
# MOV reg32,CR0/2/3/4 ; 0F 20 /r [386]
# MOV reg32,DR0/1/2/3/6/7 ; 0F 21 /r [386]
# MOV reg32,TR3/4/5/6/7 ; 0F 24 /r [386]
# MOV CR0/2/3/4,reg32 ; 0F 22 /r [386]
# MOV DR0/1/2/3/6/7,reg32 ; 0F 23 /r [386]
# MOV TR3/4/5/6/7,reg32 ; 0F 26 /r [386]
# |MOV| copies the contents of its source (second) operand into its
# destination (first) operand.
# In all forms of the |MOV| instruction, the two operands are the same
# size, except for moving between a segment register and an |r/m32|
# operand. These instructions are treated exactly like the corresponding
# 16-bit equivalent (so that, for example, |MOV DS,EAX| functions
# identically to |MOV DS,AX| but saves a prefix when in 32-bit mode),
# except that when a segment register is moved into a 32-bit destination,
# the top two bytes of the result are undefined.
# |MOV| may not use |CS| as a destination.
# |CR4| is only a supported register on the Pentium and above.
# A.103 |MOVD|: Move Doubleword to/from MMX Register
# MOVD mmxreg,r/m32 ; 0F 6E /r [PENT,MMX]
# MOVD r/m32,mmxreg ; 0F 7E /r [PENT,MMX]
# |MOVD| copies 32 bits from its source (second) operand into its
# destination (first) operand. When the destination is a 64-bit MMX
# register, the top 32 bits are set to zero.
# A.104 |MOVQ|: Move Quadword to/from MMX Register
# MOVQ mmxreg,r/m64 ; 0F 6F /r [PENT,MMX]
# MOVQ r/m64,mmxreg ; 0F 7F /r [PENT,MMX]
# |MOVQ| copies 64 bits from its source (second) operand into its
# destination (first) operand.
# A.105 |MOVSB|, |MOVSW|, |MOVSD|: Move String
# MOVSB ; A4 [8086]
# MOVSW ; o16 A5 [8086]
# MOVSD ; o32 A5 [386]
# |MOVSB| copies the byte at |[ES:DI]| or |[ES:EDI]| to |[DS:SI]| or
# |[DS:ESI]|. It then increments or decrements (depending on the direction
# flag: increments if the flag is clear, decrements if it is set) |SI| and
# |DI| (or |ESI| and |EDI|).
# The registers used are |SI| and |DI| if the address size is 16 bits, and
# |ESI| and |EDI| if it is 32 bits. If you need to use an address size not
# equal to the current |BITS| setting, you can use an explicit |a16| or
# |a32| prefix.
# The segment register used to load from |[SI]| or |[ESI]| can be
# overridden by using a segment register name as a prefix (for example,
# |es movsb|). The use of |ES| for the store to |[DI]| or |[EDI]| cannot
# be overridden.
# |MOVSW| and |MOVSD| work in the same way, but they copy a word or a
# doubleword instead of a byte, and increment or decrement the addressing
# registers by 2 or 4 instead of 1.
# The |REP| prefix may be used to repeat the instruction |CX| (or |ECX| -
# again, the address size chooses which) times.
# A.106 |MOVSX|, |MOVZX|: Move Data with Sign or Zero Extend
# MOVSX reg16,r/m8 ; o16 0F BE /r [386]
# MOVSX reg32,r/m8 ; o32 0F BE /r [386]
# MOVSX reg32,r/m16 ; o32 0F BF /r [386]
# MOVZX reg16,r/m8 ; o16 0F B6 /r [386]
# MOVZX reg32,r/m8 ; o32 0F B6 /r [386]
# MOVZX reg32,r/m16 ; o32 0F B7 /r [386]
# |MOVSX| sign-extends its source (second) operand to the length of its
# destination (first) operand, and copies the result into the destination
# operand. |MOVZX| does the same, but zero-extends rather than
# sign-extending.
# A.107 |MUL|: Unsigned Integer Multiply
# MUL r/m8 ; F6 /4 [8086]
# MUL r/m16 ; o16 F7 /4 [8086]
# MUL r/m32 ; o32 F7 /4 [386]
# |MUL| performs unsigned integer multiplication. The other operand to the
# multiplication, and the destination operand, are implicit, in the
# following way:
# * For |MUL r/m8|, |AL| is multiplied by the given operand; the
# product is stored in |AX|.
# * For |MUL r/m16|, |AX| is multiplied by the given operand; the
# product is stored in |DX:AX|.
# * For |MUL r/m32|, |EAX| is multiplied by the given operand; the
# product is stored in |EDX:EAX|.
# Signed integer multiplication is performed by the |IMUL| instruction:
# see section A.77 <#section-A.77>.
# A.108 |NEG|, |NOT|: Two's and One's Complement
# NEG r/m8 ; F6 /3 [8086]
# NEG r/m16 ; o16 F7 /3 [8086]
# NEG r/m32 ; o32 F7 /3 [386]
# NOT r/m8 ; F6 /2 [8086]
# NOT r/m16 ; o16 F7 /2 [8086]
# NOT r/m32 ; o32 F7 /2 [386]
# |NEG| replaces the contents of its operand by the two's complement
# negation (invert all the bits and then add one) of the original value.
# |NOT|, similarly, performs one's complement (inverts all the bits).
# A.109 |NOP|: No Operation
# NOP ; 90 [8086]
# |NOP| performs no operation. Its opcode is the same as that generated by
# |XCHG AX,AX| or |XCHG EAX,EAX| (depending on the processor mode; see
# section A.168 <#section-A.168>).
# A.110 |OR|: Bitwise OR
# OR r/m8,reg8 ; 08 /r [8086]
# OR r/m16,reg16 ; o16 09 /r [8086]
# OR r/m32,reg32 ; o32 09 /r [386]
# OR reg8,r/m8 ; 0A /r [8086]
# OR reg16,r/m16 ; o16 0B /r [8086]
# OR reg32,r/m32 ; o32 0B /r [386]
# OR r/m8,imm8 ; 80 /1 ib [8086]
# OR r/m16,imm16 ; o16 81 /1 iw [8086]
# OR r/m32,imm32 ; o32 81 /1 id [386]
# OR r/m16,imm8 ; o16 83 /1 ib [8086]
# OR r/m32,imm8 ; o32 83 /1 ib [386]
# OR AL,imm8 ; 0C ib [8086]
# OR AX,imm16 ; o16 0D iw [8086]
# OR EAX,imm32 ; o32 0D id [386]
# |OR| performs a bitwise OR operation between its two operands (i.e. each
# bit of the result is 1 if and only if at least one of the corresponding
# bits of the two inputs was 1), and stores the result in the destination
# (first) operand.
# In the forms with an 8-bit immediate second operand and a longer first
# operand, the second operand is considered to be signed, and is
# sign-extended to the length of the first operand. In these cases, the
# |BYTE| qualifier is necessary to force NASM to generate this form of the
# instruction.
# The MMX instruction |POR| (see section A.129 <#section-A.129>) performs
# the same operation on the 64-bit MMX registers.
# A.111 |OUT|: Output Data to I/O Port
# OUT imm8,AL ; E6 ib [8086]
# OUT imm8,AX ; o16 E7 ib [8086]
# OUT imm8,EAX ; o32 E7 ib [386]
# OUT DX,AL ; EE [8086]
# OUT DX,AX ; o16 EF [8086]
# OUT DX,EAX ; o32 EF [386]
# |IN| writes the contents of the given source register to the specified
# I/O port. The port number may be specified as an immediate value if it
# is between 0 and 255, and otherwise must be stored in |DX|. See also
# |IN| (section A.78 <#section-A.78>).
# A.112 |OUTSB|, |OUTSW|, |OUTSD|: Output String to I/O Port
# OUTSB ; 6E [186]
# OUTSW ; o16 6F [186]
# OUTSD ; o32 6F [386]
# |OUTSB| loads a byte from |[DS:SI]| or |[DS:ESI]| and writes it to the
# I/O port specified in |DX|. It then increments or decrements (depending
# on the direction flag: increments if the flag is clear, decrements if it
# is set) |SI| or |ESI|.
# The register used is |SI| if the address size is 16 bits, and |ESI| if
# it is 32 bits. If you need to use an address size not equal to the
# current |BITS| setting, you can use an explicit |a16| or |a32| prefix.
# The segment register used to load from |[SI]| or |[ESI]| can be
# overridden by using a segment register name as a prefix (for example,
# |es outsb|).
# |OUTSW| and |OUTSD| work in the same way, but they output a word or a
# doubleword instead of a byte, and increment or decrement the addressing
# registers by 2 or 4 instead of 1.
# The |REP| prefix may be used to repeat the instruction |CX| (or |ECX| -
# again, the address size chooses which) times.
# A.113 |PACKSSDW|, |PACKSSWB|, |PACKUSWB|: Pack Data
# PACKSSDW mmxreg,r/m64 ; 0F 6B /r [PENT,MMX]
# PACKSSWB mmxreg,r/m64 ; 0F 63 /r [PENT,MMX]
# PACKUSWB mmxreg,r/m64 ; 0F 67 /r [PENT,MMX]
# All these instructions start by forming a notional 128-bit word by
# placing the source (second) operand on the left of the destination
# (first) operand. |PACKSSDW| then splits this 128-bit word into four
# doublewords, converts each to a word, and loads them side by side into
# the destination register; |PACKSSWB| and |PACKUSWB| both split the
# 128-bit word into eight words, converts each to a byte, and loads
# /those/ side by side into the destination register.
# |PACKSSDW| and |PACKSSWB| perform signed saturation when reducing the
# length of numbers: if the number is too large to fit into the reduced
# space, they replace it by the largest signed number (|7FFFh| or |7Fh|)
# that /will/ fit, and if it is too small then they replace it by the
# smallest signed number (|8000h| or |80h|) that will fit. |PACKUSWB|
# performs unsigned saturation: it treats its input as unsigned, and
# replaces it by the largest unsigned number that will fit.
# A.114 |PADDxx|: MMX Packed Addition
# PADDB mmxreg,r/m64 ; 0F FC /r [PENT,MMX]
# PADDW mmxreg,r/m64 ; 0F FD /r [PENT,MMX]
# PADDD mmxreg,r/m64 ; 0F FE /r [PENT,MMX]
# PADDSB mmxreg,r/m64 ; 0F EC /r [PENT,MMX]
# PADDSW mmxreg,r/m64 ; 0F ED /r [PENT,MMX]
# PADDUSB mmxreg,r/m64 ; 0F DC /r [PENT,MMX]
# PADDUSW mmxreg,r/m64 ; 0F DD /r [PENT,MMX]
# |PADDxx| all perform packed addition between their two 64-bit operands,
# storing the result in the destination (first) operand. The |PADDxB|
# forms treat the 64-bit operands as vectors of eight bytes, and add each
# byte individually; |PADDxW| treat the operands as vectors of four words;
# and |PADDD| treats its operands as vectors of two doublewords.
# |PADDSB| and |PADDSW| perform signed saturation on the sum of each pair
# of bytes or words: if the result of an addition is too large or too
# small to fit into a signed byte or word result, it is clipped
# (saturated) to the largest or smallest value which /will/ fit. |PADDUSB|
# and |PADDUSW| similarly perform unsigned saturation, clipping to |0FFh|
# or |0FFFFh| if the result is larger than that.
# A.115 |PADDSIW|: MMX Packed Addition to Implicit Destination
# PADDSIW mmxreg,r/m64 ; 0F 51 /r [CYRIX,MMX]
# |PADDSIW|, specific to the Cyrix extensions to the MMX instruction set,
# performs the same function as |PADDSW|, except that the result is not
# placed in the register specified by the first operand, but instead in
# the register whose number differs from the first operand only in the
# last bit. So |PADDSIW MM0,MM2| would put the result in |MM1|, but
# |PADDSIW MM1,MM2| would put the result in |MM0|.
# A.116 |PAND|, |PANDN|: MMX Bitwise AND and AND-NOT
# PAND mmxreg,r/m64 ; 0F DB /r [PENT,MMX]
# PANDN mmxreg,r/m64 ; 0F DF /r [PENT,MMX]
# |PAND| performs a bitwise AND operation between its two operands (i.e.
# each bit of the result is 1 if and only if the corresponding bits of the
# two inputs were both 1), and stores the result in the destination
# (first) operand.
# |PANDN| performs the same operation, but performs a one's complement
# operation on the destination (first) operand first.
# A.117 |PAVEB|: MMX Packed Average
# PAVEB mmxreg,r/m64 ; 0F 50 /r [CYRIX,MMX]
# |PAVEB|, specific to the Cyrix MMX extensions, treats its two operands
# as vectors of eight unsigned bytes, and calculates the average of the
# corresponding bytes in the operands. The resulting vector of eight
# averages is stored in the first operand.
# A.118 |PCMPxx|: MMX Packed Comparison
# PCMPEQB mmxreg,r/m64 ; 0F 74 /r [PENT,MMX]
# PCMPEQW mmxreg,r/m64 ; 0F 75 /r [PENT,MMX]
# PCMPEQD mmxreg,r/m64 ; 0F 76 /r [PENT,MMX]
# PCMPGTB mmxreg,r/m64 ; 0F 64 /r [PENT,MMX]
# PCMPGTW mmxreg,r/m64 ; 0F 65 /r [PENT,MMX]
# PCMPGTD mmxreg,r/m64 ; 0F 66 /r [PENT,MMX]
# The |PCMPxx| instructions all treat their operands as vectors of bytes,
# words, or doublewords; corresponding elements of the source and
# destination are compared, and the corresponding element of the
# destination (first) operand is set to all zeros or all ones depending on
# the result of the comparison.
# |PCMPxxB| treats the operands as vectors of eight bytes, |PCMPxxW|
# treats them as vectors of four words, and |PCMPxxD| as two doublewords.
# |PCMPEQx| sets the corresponding element of the destination operand to
# all ones if the two elements compared are equal; |PCMPGTx| sets the
# destination element to all ones if the element of the first
# (destination) operand is greater (treated as a signed integer) than that
# of the second (source) operand.
# A.119 |PDISTIB|: MMX Packed Distance and Accumulate with Implied
# Register
# PDISTIB mmxreg,mem64 ; 0F 54 /r [CYRIX,MMX]
# |PDISTIB|, specific to the Cyrix MMX extensions, treats its two input
# operands as vectors of eight unsigned bytes. For each byte position, it
# finds the absolute difference between the bytes in that position in the
# two input operands, and adds that value to the byte in the same position
# in the implied output register. The addition is saturated to an unsigned
# byte in the same way as |PADDUSB|.
# The implied output register is found in the same way as |PADDSIW|
# (section A.115 <#section-A.115>).
# Note that |PDISTIB| cannot take a register as its second source operand.
# A.120 |PMACHRIW|: MMX Packed Multiply and Accumulate with Rounding
# PMACHRIW mmxreg,mem64 ; 0F 5E /r [CYRIX,MMX]
# |PMACHRIW| acts almost identically to |PMULHRIW| (section A.123
# <#section-A.123>), but instead of /storing/ its result in the implied
# destination register, it /adds/ its result, as four packed words, to the
# implied destination register. No saturation is done: the addition can
# wrap around.
# Note that |PMACHRIW| cannot take a register as its second source operand.
# A.121 |PMADDWD|: MMX Packed Multiply and Add
# PMADDWD mmxreg,r/m64 ; 0F F5 /r [PENT,MMX]
# |PMADDWD| treats its two inputs as vectors of four signed words. It
# multiplies corresponding elements of the two operands, giving four
# signed doubleword results. The top two of these are added and placed in
# the top 32 bits of the destination (first) operand; the bottom two are
# added and placed in the bottom 32 bits.
# A.122 |PMAGW|: MMX Packed Magnitude
# PMAGW mmxreg,r/m64 ; 0F 52 /r [CYRIX,MMX]
# |PMAGW|, specific to the Cyrix MMX extensions, treats both its operands
# as vectors of four signed words. It compares the absolute values of the
# words in corresponding positions, and sets each word of the destination
# (first) operand to whichever of the two words in that position had the
# larger absolute value.
# A.123 |PMULHRW|, |PMULHRIW|: MMX Packed Multiply High with Rounding
# PMULHRW mmxreg,r/m64 ; 0F 59 /r [CYRIX,MMX]
# PMULHRIW mmxreg,r/m64 ; 0F 5D /r [CYRIX,MMX]
# These instructions, specific to the Cyrix MMX extensions, treat their
# operands as vectors of four signed words. Words in corresponding
# positions are multiplied, to give a 32-bit value in which bits 30 and 31
# are guaranteed equal. Bits 30 to 15 of this value (bit mask
# |0x7FFF8000|) are taken and stored in the corresponding position of the
# destination operand, after first rounding the low bit (equivalent to
# adding |0x4000| before extracting bits 30 to 15).
# For |PMULHRW|, the destination operand is the first operand; for
# |PMULHRIW| the destination operand is implied by the first operand in
# the manner of |PADDSIW| (section A.115 <#section-A.115>).
# A.124 |PMULHW|, |PMULLW|: MMX Packed Multiply
# PMULHW mmxreg,r/m64 ; 0F E5 /r [PENT,MMX]
# PMULLW mmxreg,r/m64 ; 0F D5 /r [PENT,MMX]
# |PMULxW| treats its two inputs as vectors of four signed words. It
# multiplies corresponding elements of the two operands, giving four
# signed doubleword results.
# |PMULHW| then stores the top 16 bits of each doubleword in the
# destination (first) operand; |PMULLW| stores the bottom 16 bits of each
# doubleword in the destination operand.
# A.125 |PMVccZB|: MMX Packed Conditional Move
# PMVZB mmxreg,mem64 ; 0F 58 /r [CYRIX,MMX]
# PMVNZB mmxreg,mem64 ; 0F 5A /r [CYRIX,MMX]
# PMVLZB mmxreg,mem64 ; 0F 5B /r [CYRIX,MMX]
# PMVGEZB mmxreg,mem64 ; 0F 5C /r [CYRIX,MMX]
# These instructions, specific to the Cyrix MMX extensions, perform
# parallel conditional moves. The two input operands are treated as
# vectors of eight bytes. Each byte of the destination (first) operand is
# either written from the corresponding byte of the source (second)
# operand, or left alone, depending on the value of the byte in the
# /implied/ operand (specified in the same way as |PADDSIW|, in section
# A.115 <#section-A.115>).
# |PMVZB| performs each move if the corresponding byte in the implied
# operand is zero. |PMVNZB| moves if the byte is non-zero. |PMVLZB| moves
# if the byte is less than zero, and |PMVGEZB| moves if the byte is
# greater than or equal to zero.
# Note that these instructions cannot take a register as their second
# source operand.
# A.126 |POP|: Pop Data from Stack
# POP reg16 ; o16 58+r [8086]
# POP reg32 ; o32 58+r [386]
# POP r/m16 ; o16 8F /0 [8086]
# POP r/m32 ; o32 8F /0 [386]
# POP CS ; 0F [8086,UNDOC]
# POP DS ; 1F [8086]
# POP ES ; 07 [8086]
# POP SS ; 17 [8086]
# POP FS ; 0F A1 [386]
# POP GS ; 0F A9 [386]
# |POP| loads a value from the stack (from |[SS:SP]| or |[SS:ESP]|) and
# then increments the stack pointer.
# The address-size attribute of the instruction determines whether |SP| or
# |ESP| is used as the stack pointer: to deliberately override the default
# given by the |BITS| setting, you can use an |a16| or |a32| prefix.
# The operand-size attribute of the instruction determines whether the
# stack pointer is incremented by 2 or 4: this means that segment register
# pops in |BITS 32| mode will pop 4 bytes off the stack and discard the
# upper two of them. If you need to override that, you can use an |o16| or
# |o32| prefix.
# The above opcode listings give two forms for general-purpose register
# pop instructions: for example, |POP BX| has the two forms |5B| and |8F
# C3|. NASM will always generate the shorter form when given |POP BX|.
# NDISASM will disassemble both.
# |POP CS| is not a documented instruction, and is not supported on any
# processor above the 8086 (since they use |0Fh| as an opcode prefix for
# instruction set extensions). However, at least some 8086 processors do
# support it, and so NASM generates it for completeness.
# A.127 |POPAx|: Pop All General-Purpose Registers
# POPA ; 61 [186]
# POPAW ; o16 61 [186]
# POPAD ; o32 61 [386]
# |POPAW| pops a word from the stack into each of, successively, |DI|,
# |SI|, |BP|, nothing (it discards a word from the stack which was a
# placeholder for |SP|), |BX|, |DX|, |CX| and |AX|. It is intended to
# reverse the operation of |PUSHAW| (see section A.135 <#section-A.135>),
# but it ignores the value for |SP| that was pushed on the stack by |PUSHAW|.
# |POPAD| pops twice as much data, and places the results in |EDI|, |ESI|,
# |EBP|, nothing (placeholder for |ESP|), |EBX|, |EDX|, |ECX| and |EAX|.
# It reverses the operation of |PUSHAD|.
# |POPA| is an alias mnemonic for either |POPAW| or |POPAD|, depending on
# the current |BITS| setting.
# Note that the registers are popped in reverse order of their numeric
# values in opcodes (see section A.2.1 <#section-A.2.1>).
# A.128 |POPFx|: Pop Flags Register
# POPF ; 9D [186]
# POPFW ; o16 9D [186]
# POPFD ; o32 9D [386]
# |POPFW| pops a word from the stack and stores it in the bottom 16 bits
# of the flags register (or the whole flags register, on processors below
# a 386). |POPFD| pops a doubleword and stores it in the entire flags
# register.
# |POPF| is an alias mnemonic for either |POPFW| or |POPFD|, depending on
# the current |BITS| setting.
# See also |PUSHF| (section A.136 <#section-A.136>).
# A.129 |POR|: MMX Bitwise OR
# POR mmxreg,r/m64 ; 0F EB /r [PENT,MMX]
# |POR| performs a bitwise OR operation between its two operands (i.e.
# each bit of the result is 1 if and only if at least one of the
# corresponding bits of the two inputs was 1), and stores the result in
# the destination (first) operand.
# A.130 |PSLLx|, |PSRLx|, |PSRAx|: MMX Bit Shifts
# PSLLW mmxreg,r/m64 ; 0F F1 /r [PENT,MMX]
# PSLLW mmxreg,imm8 ; 0F 71 /6 ib [PENT,MMX]
# PSLLD mmxreg,r/m64 ; 0F F2 /r [PENT,MMX]
# PSLLD mmxreg,imm8 ; 0F 72 /6 ib [PENT,MMX]
# PSLLQ mmxreg,r/m64 ; 0F F3 /r [PENT,MMX]
# PSLLQ mmxreg,imm8 ; 0F 73 /6 ib [PENT,MMX]
# PSRAW mmxreg,r/m64 ; 0F E1 /r [PENT,MMX]
# PSRAW mmxreg,imm8 ; 0F 71 /4 ib [PENT,MMX]
# PSRAD mmxreg,r/m64 ; 0F E2 /r [PENT,MMX]
# PSRAD mmxreg,imm8 ; 0F 72 /4 ib [PENT,MMX]
# PSRLW mmxreg,r/m64 ; 0F D1 /r [PENT,MMX]
# PSRLW mmxreg,imm8 ; 0F 71 /2 ib [PENT,MMX]
# PSRLD mmxreg,r/m64 ; 0F D2 /r [PENT,MMX]
# PSRLD mmxreg,imm8 ; 0F 72 /2 ib [PENT,MMX]
# PSRLQ mmxreg,r/m64 ; 0F D3 /r [PENT,MMX]
# PSRLQ mmxreg,imm8 ; 0F 73 /2 ib [PENT,MMX]
# |PSxxQ| perform simple bit shifts on the 64-bit MMX registers: the
# destination (first) operand is shifted left or right by the number of
# bits given in the source (second) operand, and the vacated bits are
# filled in with zeros (for a logical shift) or copies of the original
# sign bit (for an arithmetic right shift).
# |PSxxW| and |PSxxD| perform packed bit shifts: the destination operand
# is treated as a vector of four words or two doublewords, and each
# element is shifted individually, so bits shifted out of one element do
# not interfere with empty bits coming into the next.
# |PSLLx| and |PSRLx| perform logical shifts: the vacated bits at one end
# of the shifted number are filled with zeros. |PSRAx| performs an
# arithmetic right shift: the vacated bits at the top of the shifted
# number are filled with copies of the original top (sign) bit.
# A.131 |PSUBxx|: MMX Packed Subtraction
# PSUBB mmxreg,r/m64 ; 0F F8 /r [PENT,MMX]
# PSUBW mmxreg,r/m64 ; 0F F9 /r [PENT,MMX]
# PSUBD mmxreg,r/m64 ; 0F FA /r [PENT,MMX]
# PSUBSB mmxreg,r/m64 ; 0F E8 /r [PENT,MMX]
# PSUBSW mmxreg,r/m64 ; 0F E9 /r [PENT,MMX]
# PSUBUSB mmxreg,r/m64 ; 0F D8 /r [PENT,MMX]
# PSUBUSW mmxreg,r/m64 ; 0F D9 /r [PENT,MMX]
# |PSUBxx| all perform packed subtraction between their two 64-bit
# operands, storing the result in the destination (first) operand. The
# |PSUBxB| forms treat the 64-bit operands as vectors of eight bytes, and
# subtract each byte individually; |PSUBxW| treat the operands as vectors
# of four words; and |PSUBD| treats its operands as vectors of two
# doublewords.
# In all cases, the elements of the operand on the right are subtracted
# from the corresponding elements of the operand on the left, not the
# other way round.
# |PSUBSB| and |PSUBSW| perform signed saturation on the sum of each pair
# of bytes or words: if the result of a subtraction is too large or too
# small to fit into a signed byte or word result, it is clipped
# (saturated) to the largest or smallest value which /will/ fit. |PSUBUSB|
# and |PSUBUSW| similarly perform unsigned saturation, clipping to |0FFh|
# or |0FFFFh| if the result is larger than that.
# A.132 |PSUBSIW|: MMX Packed Subtract with Saturation to Implied
# Destination
# PSUBSIW mmxreg,r/m64 ; 0F 55 /r [CYRIX,MMX]
# |PSUBSIW|, specific to the Cyrix extensions to the MMX instruction set,
# performs the same function as |PSUBSW|, except that the result is not
# placed in the register specified by the first operand, but instead in
# the implied destination register, specified as for |PADDSIW| (section
# A.115 <#section-A.115>).
# A.133 |PUNPCKxxx|: Unpack Data
# PUNPCKHBW mmxreg,r/m64 ; 0F 68 /r [PENT,MMX]
# PUNPCKHWD mmxreg,r/m64 ; 0F 69 /r [PENT,MMX]
# PUNPCKHDQ mmxreg,r/m64 ; 0F 6A /r [PENT,MMX]
# PUNPCKLBW mmxreg,r/m64 ; 0F 60 /r [PENT,MMX]
# PUNPCKLWD mmxreg,r/m64 ; 0F 61 /r [PENT,MMX]
# PUNPCKLDQ mmxreg,r/m64 ; 0F 62 /r [PENT,MMX]
# |PUNPCKxx| all treat their operands as vectors, and produce a new vector
# generated by interleaving elements from the two inputs. The |PUNPCKHxx|
# instructions start by throwing away the bottom half of each input
# operand, and the |PUNPCKLxx| instructions throw away the top half.
# The remaining elements, totalling 64 bits, are then interleaved into the
# destination, alternating elements from the second (source) operand and
# the first (destination) operand: so the leftmost element in the result
# always comes from the second operand, and the rightmost from the
# destination.
# |PUNPCKxBW| works a byte at a time, |PUNPCKxWD| a word at a time, and
# |PUNPCKxDQ| a doubleword at a time.
# So, for example, if the first operand held |0x7A6A5A4A3A2A1A0A| and the
# second held |0x7B6B5B4B3B2B1B0B|, then:
# * |PUNPCKHBW| would return |0x7B7A6B6A5B5A4B4A|.
# * |PUNPCKHWD| would return |0x7B6B7A6A5B4B5A4A|.
# * |PUNPCKHDQ| would return |0x7B6B5B4B7A6A5A4A|.
# * |PUNPCKLBW| would return |0x3B3A2B2A1B1A0B0A|.
# * |PUNPCKLWD| would return |0x3B2B3A2A1B0B1A0A|.
# * |PUNPCKLDQ| would return |0x3B2B1B0B3A2A1A0A|.
# A.134 |PUSH|: Push Data on Stack
# PUSH reg16 ; o16 50+r [8086]
# PUSH reg32 ; o32 50+r [386]
# PUSH r/m16 ; o16 FF /6 [8086]
# PUSH r/m32 ; o32 FF /6 [386]
# PUSH CS ; 0E [8086]
# PUSH DS ; 1E [8086]
# PUSH ES ; 06 [8086]
# PUSH SS ; 16 [8086]
# PUSH FS ; 0F A0 [386]
# PUSH GS ; 0F A8 [386]
# PUSH imm8 ; 6A ib [286]
# PUSH imm16 ; o16 68 iw [286]
# PUSH imm32 ; o32 68 id [386]
# |PUSH| decrements the stack pointer (|SP| or |ESP|) by 2 or 4, and then
# stores the given value at |[SS:SP]| or |[SS:ESP]|.
# The address-size attribute of the instruction determines whether |SP| or
# |ESP| is used as the stack pointer: to deliberately override the default
# given by the |BITS| setting, you can use an |a16| or |a32| prefix.
# The operand-size attribute of the instruction determines whether the
# stack pointer is decremented by 2 or 4: this means that segment register
# pushes in |BITS 32| mode will push 4 bytes on the stack, of which the
# upper two are undefined. If you need to override that, you can use an
# |o16| or |o32| prefix.
# The above opcode listings give two forms for general-purpose register
# push instructions: for example, |PUSH BX| has the two forms |53| and |FF
# F3|. NASM will always generate the shorter form when given |PUSH BX|.
# NDISASM will disassemble both.
# Unlike the undocumented and barely supported |POP CS|, |PUSH CS| is a
# perfectly valid and sensible instruction, supported on all processors.
# The instruction |PUSH SP| may be used to distinguish an 8086 from later
# processors: on an 8086, the value of |SP| stored is the value it has
# /after/ the push instruction, whereas on later processors it is the
# value /before/ the push instruction.
# A.135 |PUSHAx|: Push All General-Purpose Registers
# PUSHA ; 60 [186]
# PUSHAD ; o32 60 [386]
# PUSHAW ; o16 60 [186]
# |PUSHAW| pushes, in succession, |AX|, |CX|, |DX|, |BX|, |SP|, |BP|, |SI|
# and |DI| on the stack, decrementing the stack pointer by a total of 16.
# |PUSHAD| pushes, in succession, |EAX|, |ECX|, |EDX|, |EBX|, |ESP|,
# |EBP|, |ESI| and |EDI| on the stack, decrementing the stack pointer by a
# total of 32.
# In both cases, the value of |SP| or |ESP| pushed is its /original/
# value, as it had before the instruction was executed.
# |PUSHA| is an alias mnemonic for either |PUSHAW| or |PUSHAD|, depending
# on the current |BITS| setting.
# Note that the registers are pushed in order of their numeric values in
# opcodes (see section A.2.1 <#section-A.2.1>).
# See also |POPA| (section A.127 <#section-A.127>).
# A.136 |PUSHFx|: Push Flags Register
# PUSHF ; 9C [186]
# PUSHFD ; o32 9C [386]
# PUSHFW ; o16 9C [186]
# |PUSHFW| pops a word from the stack and stores it in the bottom 16 bits
# of the flags register (or the whole flags register, on processors below
# a 386). |PUSHFD| pops a doubleword and stores it in the entire flags
# register.
# |PUSHF| is an alias mnemonic for either |PUSHFW| or |PUSHFD|, depending
# on the current |BITS| setting.
# See also |POPF| (section A.128 <#section-A.128>).
# A.137 |PXOR|: MMX Bitwise XOR
# PXOR mmxreg,r/m64 ; 0F EF /r [PENT,MMX]
# |PXOR| performs a bitwise XOR operation between its two operands (i.e.
# each bit of the result is 1 if and only if exactly one of the
# corresponding bits of the two inputs was 1), and stores the result in
# the destination (first) operand.
# A.138 |RCL|, |RCR|: Bitwise Rotate through Carry Bit
# RCL r/m8,1 ; D0 /2 [8086]
# RCL r/m8,CL ; D2 /2 [8086]
# RCL r/m8,imm8 ; C0 /2 ib [286]
# RCL r/m16,1 ; o16 D1 /2 [8086]
# RCL r/m16,CL ; o16 D3 /2 [8086]
# RCL r/m16,imm8 ; o16 C1 /2 ib [286]
# RCL r/m32,1 ; o32 D1 /2 [386]
# RCL r/m32,CL ; o32 D3 /2 [386]
# RCL r/m32,imm8 ; o32 C1 /2 ib [386]
# RCR r/m8,1 ; D0 /3 [8086]
# RCR r/m8,CL ; D2 /3 [8086]
# RCR r/m8,imm8 ; C0 /3 ib [286]
# RCR r/m16,1 ; o16 D1 /3 [8086]
# RCR r/m16,CL ; o16 D3 /3 [8086]
# RCR r/m16,imm8 ; o16 C1 /3 ib [286]
# RCR r/m32,1 ; o32 D1 /3 [386]
# RCR r/m32,CL ; o32 D3 /3 [386]
# RCR r/m32,imm8 ; o32 C1 /3 ib [386]
# |RCL| and |RCR| perform a 9-bit, 17-bit or 33-bit bitwise rotation
# operation, involving the given source/destination (first) operand and
# the carry bit. Thus, for example, in the operation |RCR AL,1|, a 9-bit
# rotation is performed in which |AL| is shifted left by 1, the top bit of
# |AL| moves into the carry flag, and the original value of the carry flag
# is placed in the low bit of |AL|.
# The number of bits to rotate by is given by the second operand. Only the
# bottom five bits of the rotation count are considered by processors
# above the 8086.
# You can force the longer (286 and upwards, beginning with a |C1| byte)
# form of |RCL foo,1| by using a |BYTE| prefix: |RCL foo,BYTE 1|.
# Similarly with |RCR|.
# A.139 |RDMSR|: Read Model-Specific Registers
# RDMSR ; 0F 32 [PENT]
# |RDMSR| reads the processor Model-Specific Register (MSR) whose index is
# stored in |ECX|, and stores the result in |EDX:EAX|. See also |WRMSR|
# (section A.165 <#section-A.165>).
# A.140 |RDPMC|: Read Performance-Monitoring Counters
# RDPMC ; 0F 33 [P6]
# |RDPMC| reads the processor performance-monitoring counter whose index
# is stored in |ECX|, and stores the result in |EDX:EAX|.
# A.141 |RDTSC|: Read Time-Stamp Counter
# RDTSC ; 0F 31 [PENT]
# |RDTSC| reads the processor's time-stamp counter into |EDX:EAX|.
# A.142 |RET|, |RETF|, |RETN|: Return from Procedure Call
# RET ; C3 [8086]
# RET imm16 ; C2 iw [8086]
# RETF ; CB [8086]
# RETF imm16 ; CA iw [8086]
# RETN ; C3 [8086]
# RETN imm16 ; C2 iw [8086]
# |RET|, and its exact synonym |RETN|, pop |IP| or |EIP| from the stack
# and transfer control to the new address. Optionally, if a numeric second
# operand is provided, they increment the stack pointer by a further
# |imm16| bytes after popping the return address.
# |RETF| executes a far return: after popping |IP|/|EIP|, it then pops
# |CS|, and /then/ increments the stack pointer by the optional argument
# if present.
# A.143 |ROL|, |ROR|: Bitwise Rotate
# ROL r/m8,1 ; D0 /0 [8086]
# ROL r/m8,CL ; D2 /0 [8086]
# ROL r/m8,imm8 ; C0 /0 ib [286]
# ROL r/m16,1 ; o16 D1 /0 [8086]
# ROL r/m16,CL ; o16 D3 /0 [8086]
# ROL r/m16,imm8 ; o16 C1 /0 ib [286]
# ROL r/m32,1 ; o32 D1 /0 [386]
# ROL r/m32,CL ; o32 D3 /0 [386]
# ROL r/m32,imm8 ; o32 C1 /0 ib [386]
# ROR r/m8,1 ; D0 /1 [8086]
# ROR r/m8,CL ; D2 /1 [8086]
# ROR r/m8,imm8 ; C0 /1 ib [286]
# ROR r/m16,1 ; o16 D1 /1 [8086]
# ROR r/m16,CL ; o16 D3 /1 [8086]
# ROR r/m16,imm8 ; o16 C1 /1 ib [286]
# ROR r/m32,1 ; o32 D1 /1 [386]
# ROR r/m32,CL ; o32 D3 /1 [386]
# ROR r/m32,imm8 ; o32 C1 /1 ib [386]
# |ROL| and |ROR| perform a bitwise rotation operation on the given
# source/destination (first) operand. Thus, for example, in the operation
# |ROR AL,1|, an 8-bit rotation is performed in which |AL| is shifted left
# by 1 and the original top bit of |AL| moves round into the low bit.
# The number of bits to rotate by is given by the second operand. Only the
# bottom 3, 4 or 5 bits (depending on the source operand size) of the
# rotation count are considered by processors above the 8086.
# You can force the longer (286 and upwards, beginning with a |C1| byte)
# form of |ROL foo,1| by using a |BYTE| prefix: |ROL foo,BYTE 1|.
# Similarly with |ROR|.
# A.144 |RSM|: Resume from System-Management Mode
# RSM ; 0F AA [PENT]
# |RSM| returns the processor to its normal operating mode when it was in
# System-Management Mode.
# A.145 |SAHF|: Store AH to Flags
# SAHF ; 9E [8086]
# |SAHF| sets the low byte of the flags word according to the contents of
# the |AH| register. See also |LAHF| (section A.90 <#section-A.90>).
# A.146 |SAL|, |SAR|: Bitwise Arithmetic Shifts
# SAL r/m8,1 ; D0 /4 [8086]
# SAL r/m8,CL ; D2 /4 [8086]
# SAL r/m8,imm8 ; C0 /4 ib [286]
# SAL r/m16,1 ; o16 D1 /4 [8086]
# SAL r/m16,CL ; o16 D3 /4 [8086]
# SAL r/m16,imm8 ; o16 C1 /4 ib [286]
# SAL r/m32,1 ; o32 D1 /4 [386]
# SAL r/m32,CL ; o32 D3 /4 [386]
# SAL r/m32,imm8 ; o32 C1 /4 ib [386]
# SAR r/m8,1 ; D0 /0 [8086]
# SAR r/m8,CL ; D2 /0 [8086]
# SAR r/m8,imm8 ; C0 /0 ib [286]
# xxSAR r/m16,1 ; o16 D1 /0 [8086]
# SAR r/m16,CL ; o16 D3 /0 [8086]
# SAR r/m16,imm8 ; o16 C1 /0 ib [286]
# xxSAR r/m32,1 ; o32 D1 /0 [386]
# SAR r/m32,CL ; o32 D3 /0 [386]
# SAR r/m32,imm8 ; o32 C1 /0 ib [386]
# |SAL| and |SAR| perform an arithmetic shift operation on the given
# source/destination (first) operand. The vacated bits are filled with
# zero for |SAL|, and with copies of the original high bit of the source
# operand for |SAR|.
# |SAL| is a synonym for |SHL| (see section A.152 <#section-A.152>). NASM
# will assemble either one to the same code, but NDISASM will always
# disassemble that code as |SHL|.
# The number of bits to shift by is given by the second operand. Only the
# bottom 3, 4 or 5 bits (depending on the source operand size) of the
# shift count are considered by processors above the 8086.
# You can force the longer (286 and upwards, beginning with a |C1| byte)
# form of |SAL foo,1| by using a |BYTE| prefix: |SAL foo,BYTE 1|.
# Similarly with |SAR|.
# A.147 |SALC|: Set AL from Carry Flag
# SALC ; D6 [8086,UNDOC]
# |SALC| is an early undocumented instruction similar in concept to
# |SETcc| (section A.150 <#section-A.150>). Its function is to set |AL| to
# zero if the carry flag is clear, or to |0xFF| if it is set.
# A.148 |SBB|: Subtract with Borrow
# SBB r/m8,reg8 ; 18 /r [8086]
# SBB r/m16,reg16 ; o16 19 /r [8086]
# SBB r/m32,reg32 ; o32 19 /r [386]
# SBB reg8,r/m8 ; 1A /r [8086]
# SBB reg16,r/m16 ; o16 1B /r [8086]
# SBB reg32,r/m32 ; o32 1B /r [386]
# SBB r/m8,imm8 ; 80 /3 ib [8086]
# SBB r/m16,imm16 ; o16 81 /3 iw [8086]
# SBB r/m32,imm32 ; o32 81 /3 id [386]
# SBB r/m16,imm8 ; o16 83 /3 ib [8086]
# SBB r/m32,imm8 ; o32 83 /3 ib [8086]
# SBB AL,imm8 ; 1C ib [8086]
# SBB AX,imm16 ; o16 1D iw [8086]
# SBB EAX,imm32 ; o32 1D id [386]
# |SBB| performs integer subtraction: it subtracts its second operand,
# plus the value of the carry flag, from its first, and leaves the result
# in its destination (first) operand. The flags are set according to the
# result of the operation: in particular, the carry flag is affected and
# can be used by a subsequent |SBB| instruction.
# In the forms with an 8-bit immediate second operand and a longer first
# operand, the second operand is considered to be signed, and is
# sign-extended to the length of the first operand. In these cases, the
# |BYTE| qualifier is necessary to force NASM to generate this form of the
# instruction.
# To subtract one number from another without also subtracting the
# contents of the carry flag, use |SUB| (section A.159 <#section-A.159>).
# A.149 |SCASB|, |SCASW|, |SCASD|: Scan String
# SCASB ; AE [8086]
# SCASW ; o16 AF [8086]
# SCASD ; o32 AF [386]
# |SCASB| compares the byte in |AL| with the byte at |[ES:DI]| or
# |[ES:EDI]|, and sets the flags accordingly. It then increments or
# decrements (depending on the direction flag: increments if the flag is
# clear, decrements if it is set) |DI| (or |EDI|).
# The register used is |DI| if the address size is 16 bits, and |EDI| if
# it is 32 bits. If you need to use an address size not equal to the
# current |BITS| setting, you can use an explicit |a16| or |a32| prefix.
# Segment override prefixes have no effect for this instruction: the use
# of |ES| for the load from |[DI]| or |[EDI]| cannot be overridden.
# |SCASW| and |SCASD| work in the same way, but they compare a word to
# |AX| or a doubleword to |EAX| instead of a byte to |AL|, and increment
# or decrement the addressing registers by 2 or 4 instead of 1.
# The |REPE| and |REPNE| prefixes (equivalently, |REPZ| and |REPNZ|) may
# be used to repeat the instruction up to |CX| (or |ECX| - again, the
# address size chooses which) times until the first unequal or equal byte
# is found.
# A.150 |SETcc|: Set Register from Condition
# SETcc r/m8 ; 0F 90+cc /2 [386]
# |SETcc| sets the given 8-bit operand to zero if its condition is not
# satisfied, and to 1 if it is.
# A.151 |SGDT|, |SIDT|, |SLDT|: Store Descriptor Table Pointers
# SGDT mem ; 0F 01 /0 [286,PRIV]
# SIDT mem ; 0F 01 /1 [286,PRIV]
# SLDT r/m16 ; 0F 00 /0 [286,PRIV]
# |SGDT| and |SIDT| both take a 6-byte memory area as an operand: they
# store the contents of the GDTR (global descriptor table register) or
# IDTR (interrupt descriptor table register) into that area as a 32-bit
# linear address and a 16-bit size limit from that area (in that order).
# These are the only instructions which directly use /linear/ addresses,
# rather than segment/offset pairs.
# |SLDT| stores the segment selector corresponding to the LDT (local
# descriptor table) into the given operand.
# See also |LGDT|, |LIDT| and |LLDT| (section A.95 <#section-A.95>).
# A.152 |SHL|, |SHR|: Bitwise Logical Shifts
# SHL r/m8,1 ; D0 /4 [8086]
# SHL r/m8,CL ; D2 /4 [8086]
# SHL r/m8,imm8 ; C0 /4 ib [286]
# SHL r/m16,1 ; o16 D1 /4 [8086]
# SHL r/m16,CL ; o16 D3 /4 [8086]
# SHL r/m16,imm8 ; o16 C1 /4 ib [286]
# SHL r/m32,1 ; o32 D1 /4 [386]
# SHL r/m32,CL ; o32 D3 /4 [386]
# SHL r/m32,imm8 ; o32 C1 /4 ib [386]
# SHR r/m8,1 ; D0 /5 [8086]
# SHR r/m8,CL ; D2 /5 [8086]
# SHR r/m8,imm8 ; C0 /5 ib [286]
# SHR r/m16,1 ; o16 D1 /5 [8086]
# SHR r/m16,CL ; o16 D3 /5 [8086]
# SHR r/m16,imm8 ; o16 C1 /5 ib [286]
# SHR r/m32,1 ; o32 D1 /5 [386]
# SHR r/m32,CL ; o32 D3 /5 [386]
# SHR r/m32,imm8 ; o32 C1 /5 ib [386]
# |SHL| and |SHR| perform a logical shift operation on the given
# source/destination (first) operand. The vacated bits are filled with zero.
# A synonym for |SHL| is |SAL| (see section A.146 <#section-A.146>). NASM
# will assemble either one to the same code, but NDISASM will always
# disassemble that code as |SHL|.
# The number of bits to shift by is given by the second operand. Only the
# bottom 3, 4 or 5 bits (depending on the source operand size) of the
# shift count are considered by processors above the 8086.
# You can force the longer (286 and upwards, beginning with a |C1| byte)
# form of |SHL foo,1| by using a |BYTE| prefix: |SHL foo,BYTE 1|.
# Similarly with |SHR|.
# A.153 |SHLD|, |SHRD|: Bitwise Double-Precision Shifts
# SHLD r/m16,reg16,imm8 ; o16 0F A4 /r ib [386]
# SHLD r/m16,reg32,imm8 ; o32 0F A4 /r ib [386]
# SHLD r/m16,reg16,CL ; o16 0F A5 /r [386]
# SHLD r/m16,reg32,CL ; o32 0F A5 /r [386]
# SHRD r/m16,reg16,imm8 ; o16 0F AC /r ib [386]
# SHRD r/m32,reg32,imm8 ; o32 0F AC /r ib [386]
# SHRD r/m16,reg16,CL ; o16 0F AD /r [386]
# SHRD r/m32,reg32,CL ; o32 0F AD /r [386]
# |SHLD| performs a double-precision left shift. It notionally places its
# second operand to the right of its first, then shifts the entire bit
# string thus generated to the left by a number of bits specified in the
# third operand. It then updates only the /first/ operand according to the
# result of this. The second operand is not modified.
# |SHRD| performs the corresponding right shift: it notionally places the
# second operand to the /left/ of the first, shifts the whole bit string
# right, and updates only the first operand.
# For example, if |EAX| holds |0x01234567| and |EBX| holds |0x89ABCDEF|,
# then the instruction |SHLD EAX,EBX,4| would update |EAX| to hold
# |0x12345678|. Under the same conditions, |SHRD EAX,EBX,4| would update
# |EAX| to hold |0xF0123456|.
# The number of bits to shift by is given by the third operand. Only the
# bottom 5 bits of the shift count are considered.
# A.154 |SMI|: System Management Interrupt
# SMI ; F1 [386,UNDOC]
# This is an opcode apparently supported by some AMD processors (which is
# why it can generate the same opcode as |INT1|), and places the machine
# into system-management mode, a special debugging mode.
# A.155 |SMSW|: Store Machine Status Word
# SMSW r/m16 ; 0F 01 /4 [286,PRIV]
# |SMSW| stores the bottom half of the |CR0| control register (or the
# Machine Status Word, on 286 processors) into the destination operand.
# See also |LMSW| (section A.96 <#section-A.96>).
# A.156 |STC|, |STD|, |STI|: Set Flags
# STC ; F9 [8086]
# STD ; FD [8086]
# STI ; FB [8086]
# These instructions set various flags. |STC| sets the carry flag; |STD|
# sets the direction flag; and |STI| sets the interrupt flag (thus
# enabling interrupts).
# To clear the carry, direction, or interrupt flags, use the |CLC|, |CLD|
# and |CLI| instructions (section A.15 <#section-A.15>). To invert the
# carry flag, use |CMC| (section A.16 <#section-A.16>).
# A.157 |STOSB|, |STOSW|, |STOSD|: Store Byte to String
# STOSB ; AA [8086]
# STOSW ; o16 AB [8086]
# STOSD ; o32 AB [386]
# |STOSB| stores the byte in |AL| at |[ES:DI]| or |[ES:EDI]|, and sets the
# flags accordingly. It then increments or decrements (depending on the
# direction flag: increments if the flag is clear, decrements if it is
# set) |DI| (or |EDI|).
# The register used is |DI| if the address size is 16 bits, and |EDI| if
# it is 32 bits. If you need to use an address size not equal to the
# current |BITS| setting, you can use an explicit |a16| or |a32| prefix.
# Segment override prefixes have no effect for this instruction: the use
# of |ES| for the store to |[DI]| or |[EDI]| cannot be overridden.
# |STOSW| and |STOSD| work in the same way, but they store the word in
# |AX| or the doubleword in |EAX| instead of the byte in |AL|, and
# increment or decrement the addressing registers by 2 or 4 instead of 1.
# The |REP| prefix may be used to repeat the instruction |CX| (or |ECX| -
# again, the address size chooses which) times.
# A.158 |STR|: Store Task Register
# STR r/m16 ; 0F 00 /1 [286,PRIV]
# |STR| stores the segment selector corresponding to the contents of the
# Task Register into its operand.
# A.159 |SUB|: Subtract Integers
# SUB r/m8,reg8 ; 28 /r [8086]
# SUB r/m16,reg16 ; o16 29 /r [8086]
# SUB r/m32,reg32 ; o32 29 /r [386]
# SUB reg8,r/m8 ; 2A /r [8086]
# SUB reg16,r/m16 ; o16 2B /r [8086]
# SUB reg32,r/m32 ; o32 2B /r [386]
# SUB r/m8,imm8 ; 80 /5 ib [8086]
# SUB r/m16,imm16 ; o16 81 /5 iw [8086]
# SUB r/m32,imm32 ; o32 81 /5 id [386]
# SUB r/m16,imm8 ; o16 83 /5 ib [8086]
# SUB r/m32,imm8 ; o32 83 /5 ib [386]
# SUB AL,imm8 ; 2C ib [8086]
# SUB AX,imm16 ; o16 2D iw [8086]
# SUB EAX,imm32 ; o32 2D id [386]
# |SUB| performs integer subtraction: it subtracts its second operand from
# its first, and leaves the result in its destination (first) operand. The
# flags are set according to the result of the operation: in particular,
# the carry flag is affected and can be used by a subsequent |SBB|
# instruction (section A.148 <#section-A.148>).
# In the forms with an 8-bit immediate second operand and a longer first
# operand, the second operand is considered to be signed, and is
# sign-extended to the length of the first operand. In these cases, the
# |BYTE| qualifier is necessary to force NASM to generate this form of the
# instruction.
# A.160 |TEST|: Test Bits (notional bitwise AND)
# TEST r/m8,reg8 ; 84 /r [8086]
# TEST r/m16,reg16 ; o16 85 /r [8086]
# TEST r/m32,reg32 ; o32 85 /r [386]
# TEST r/m8,imm8 ; F6 /7 ib [8086]
# TEST r/m16,imm16 ; o16 F7 /7 iw [8086]
# TEST r/m32,imm32 ; o32 F7 /7 id [386]
# TEST AL,imm8 ; A8 ib [8086]
# TEST AX,imm16 ; o16 A9 iw [8086]
# TEST EAX,imm32 ; o32 A9 id [386]
# |TEST| performs a `mental' bitwise AND of its two operands, and affects
# the flags as if the operation had taken place, but does not store the
# result of the operation anywhere.
# A.161 |UMOV|: User Move Data
# UMOV r/m8,reg8 ; 0F 10 /r [386,UNDOC]
# UMOV r/m16,reg16 ; o16 0F 11 /r [386,UNDOC]
# UMOV r/m32,reg32 ; o32 0F 11 /r [386,UNDOC]
# UMOV reg8,r/m8 ; 0F 12 /r [386,UNDOC]
# UMOV reg16,r/m16 ; o16 0F 13 /r [386,UNDOC]
# UMOV reg32,r/m32 ; o32 0F 13 /r [386,UNDOC]
# This undocumented instruction is used by in-circuit emulators to access
# user memory (as opposed to host memory). It is used just like an
# ordinary memory/register or register/register |MOV| instruction, but
# accesses user space.
# A.162 |VERR|, |VERW|: Verify Segment Readability/Writability
# VERR r/m16 ; 0F 00 /4 [286,PRIV]
# VERW r/m16 ; 0F 00 /5 [286,PRIV]
# |VERR| sets the zero flag if the segment specified by the selector in
# its operand can be read from at the current privilege level. |VERW| sets
# the zero flag if the segment can be written.
# A.163 |WAIT|: Wait for Floating-Point Processor
# WAIT ; 9B [8086]
# |WAIT|, on 8086 systems with a separate 8087 FPU, waits for the FPU to
# have finished any operation it is engaged in before continuing main
# processor operations, so that (for example) an FPU store to main memory
# can be guaranteed to have completed before the CPU tries to read the
# result back out.
# On higher processors, |WAIT| is unnecessary for this purpose, and it has
# the alternative purpose of ensuring that any pending unmasked FPU
# exceptions have happened before execution continues.
# A.164 |WBINVD|: Write Back and Invalidate Cache
# WBINVD ; 0F 09 [486]
# |WBINVD| invalidates and empties the processor's internal caches, and
# causes the processor to instruct external caches to do the same. It
# writes the contents of the caches back to memory first, so no data is
# lost. To flush the caches quickly without bothering to write the data
# back first, use |INVD| (section A.84 <#section-A.84>).
# A.165 |WRMSR|: Write Model-Specific Registers
# WRMSR ; 0F 30 [PENT]
# |WRMSR| writes the value in |EDX:EAX| to the processor Model-Specific
# Register (MSR) whose index is stored in |ECX|. See also |RDMSR| (section
# A.139 <#section-A.139>).
# A.166 |XADD|: Exchange and Add
# XADD r/m8,reg8 ; 0F C0 /r [486]
# XADD r/m16,reg16 ; o16 0F C1 /r [486]
# XADD r/m32,reg32 ; o32 0F C1 /r [486]
# |XADD| exchanges the values in its two operands, and then adds them
# together and writes the result into the destination (first) operand.
# This instruction can be used with a |LOCK| prefix for multi-processor
# synchronisation purposes.
# A.167 |XBTS|: Extract Bit String
# XBTS reg16,r/m16 ; o16 0F A6 /r [386,UNDOC]
# XBTS reg32,r/m32 ; o32 0F A6 /r [386,UNDOC]
# No clear documentation seems to be available for this instruction: the
# best I've been able to find reads `Takes a string of bits from the first
# operand and puts them in the second operand'. It is present only in
# early 386 processors, and conflicts with the opcodes for |CMPXCHG486|.
# NASM supports it only for completeness. Its counterpart is |IBTS| (see
# section A.75 <#section-A.75>).
# A.168 |XCHG|: Exchange
# XCHG reg8,r/m8 ; 86 /r [8086]
# XCHG reg16,r/m8 ; o16 87 /r [8086]
# XCHG reg32,r/m32 ; o32 87 /r [386]
# XCHG r/m8,reg8 ; 86 /r [8086]
# XCHG r/m16,reg16 ; o16 87 /r [8086]
# XCHG r/m32,reg32 ; o32 87 /r [386]
# XCHG AX,reg16 ; o16 90+r [8086]
# XCHG EAX,reg32 ; o32 90+r [386]
# XCHG reg16,AX ; o16 90+r [8086]
# XCHG reg32,EAX ; o32 90+r [386]
# |XCHG| exchanges the values in its two operands. It can be used with a
# |LOCK| prefix for purposes of multi-processor synchronisation.
# |XCHG AX,AX| or |XCHG EAX,EAX| (depending on the |BITS| setting)
# generates the opcode |90h|, and so is a synonym for |NOP| (section A.109
# <#section-A.109>).
# A.169 |XLATB|: Translate Byte in Lookup Table
# XLATB ; D7 [8086]
# |XLATB| adds the value in |AL|, treated as an unsigned byte, to |BX| or
# |EBX|, and loads the byte from the resulting address (in the segment
# specified by |DS|) back into |AL|.
# The base register used is |BX| if the address size is 16 bits, and |EBX|
# if it is 32 bits. If you need to use an address size not equal to the
# current |BITS| setting, you can use an explicit |a16| or |a32| prefix.
# The segment register used to load from |[BX+AL]| or |[EBX+AL]| can be
# overridden by using a segment register name as a prefix (for example,
# |es xlatb|).
# A.170 |XOR|: Bitwise Exclusive OR
# XOR r/m8,reg8 ; 30 /r [8086]
# XOR r/m16,reg16 ; o16 31 /r [8086]
# XOR r/m32,reg32 ; o32 31 /r [386]
# XOR reg8,r/m8 ; 32 /r [8086]
# XOR reg16,r/m16 ; o16 33 /r [8086]
# XOR reg32,r/m32 ; o32 33 /r [386]
# XOR r/m8,imm8 ; 80 /6 ib [8086]
# XOR r/m16,imm16 ; o16 81 /6 iw [8086]
# XOR r/m32,imm32 ; o32 81 /6 id [386]
# XOR r/m16,imm8 ; o16 83 /6 ib [8086]
# XOR r/m32,imm8 ; o32 83 /6 ib [386]
# XOR AL,imm8 ; 34 ib [8086]
# XOR AX,imm16 ; o16 35 iw [8086]
# XOR EAX,imm32 ; o32 35 id [386]
# |XOR| performs a bitwise XOR operation between its two operands (i.e.
# each bit of the result is 1 if and only if exactly one of the
# corresponding bits of the two inputs was 1), and stores the result in
# the destination (first) operand.
# In the forms with an 8-bit immediate second operand and a longer first
# operand, the second operand is considered to be signed, and is
# sign-extended to the length of the first operand. In these cases, the
# |BYTE| qualifier is necessary to force NASM to generate this form of the
# instruction.
# The MMX instruction |PXOR| (see section A.137 <#section-A.137>) performs
# the same operation on the 64-bit MMX registers.
# Previous Chapter <nasmdo10.html> | Contents <nasmdoc0.html> | Index
# <nasmdoci.html>

275
lib/intel/command.rb Normal file
View File

@ -0,0 +1,275 @@
require 'intel/special_register'
module Intel
##
# Command is a potential command you can call. It has an
# opcode (eg: MOV) and the memory format that it outputs as
# (opcodes) as well as the kinds of parameters it takes and the
# processor types that support the command.
# Commands are parsed from the assembler.txt file
class Command
attr_accessor :opcode, :opcodes, :processors , :parameters
def initialize opcode , opcodes , processors , parameters = nil
@opcode = opcode
@opcodes = opcodes
@processors = processors
@parameters = parameters
end
def dup
x = super
x.parameters = x.parameters.dup
x.opcodes = x.opcodes.dup
x
end
# TODO: learn this better, and figure out why not polymorphic ==
def parameter_matches a, b
return false if String === b
if a.is_a?(Register) && b.is_a?(Register) then
return a.bits == b.bits && (b.id.nil? || a.id == b.id)
end
if a.is_a?(Address) && b.is_a?(Address) then
return ! b.offset? || a.offset?
end
if a.is_a?(SpecialRegister) && b.is_a?(SpecialRegister) then
return a.class == b.class && (b.id.nil? || a.id == b.id)
end
return false unless b.is_a?(Immediate)
if a.is_a? Integer then
return (b.value && b.value == a) || b.bits.nil? || a < (2 ** b.bits)
end
if a.is_a? Label then
return (a.is_a?(FutureLabel) && a.position.nil? )? b.bits == a.machine.bits :
a.bits <= (b.bits || a.machine.bits)
end
false
end
def instruction_applies? instruction
return false if instruction.opcode != self.opcode
return false if instruction.parameters.size != self.parameters.size
instruction.parameters.zip(self.parameters).all? { |a, b|
self.parameter_matches a, b
}
end
def to_parameter parameter
case parameter
when 'r/m8' then return parameter # "Expanded by the parser"
when 'r/m16' then return parameter # "Expanded by the parser"
when 'r/m32' then return parameter # "Expanded by the parser"
when 'r/m64' then return parameter # "Expanded by the parser"
when 'TO fpureg' then return parameter # "Fixed in nasm_fixes"
when 'SHORT imm' then return parameter # "Fixed in nasm_fixes"
when 'FAR mem' then return parameter # "Fixed in nasm_fixes"
when 'FAR mem16' then return parameter # "Fixed in nasm_fixes"
when 'FAR mem32' then return parameter # "Fixed in nasm_fixes"
when 'NEAR imm' then return parameter # "Fixed in nasm_fixes"
when 'imm:imm16' then return parameter # "Fixed in nasm_fixes"
when 'imm:imm32' then return parameter # "Fixed in nasm_fixes"
when '1' then return Immediate.new(1)
when 'AL' then return Register.new(nil, 0, 8)
when 'AX' then return Register.new(nil, 0, 16)
when 'EAX' then return Register.new(nil, 0, 32)
when 'CL' then return Register.new(nil, 1, 8)
when 'CX' then return Register.new(nil, 1, 16)
when 'ECX' then return Register.new(nil, 1, 32)
when 'DL' then return Register.new(nil, 2, 8)
when 'DX' then return Register.new(nil, 2, 16)
when 'EDX' then return Register.new(nil, 2, 32)
when 'BL' then return Register.new(nil, 3, 8)
when 'BX' then return Register.new(nil, 3, 16)
when 'EBX' then return Register.new(nil, 3, 32)
when 'ES' then return SegmentRegister.new(nil, 0)
when 'CS' then return SegmentRegister.new(nil, 1)
when 'SS' then return SegmentRegister.new(nil, 2)
when 'DS' then return SegmentRegister.new(nil, 3)
when 'FS' then return SegmentRegister.new(nil, 4)
when 'GS' then return SegmentRegister.new(nil, 5)
when 'imm' then return Immediate.new
when 'imm8' then return Immediate.new(8)
when 'imm16' then return Immediate.new(16)
when 'imm32' then return Immediate.new(32)
when 'segreg' then return SegmentRegister.new
when 'reg' then return Register.new
when 'reg8' then return Register.new(nil,nil,8)
when 'reg16' then return Register.new(nil,nil,16)
when 'reg32' then return Register.new(nil,nil,32)
when 'mem' then return Address.new(false, 4)
when 'mem8' then return Address.new(false, 8)
when 'mem16' then return Address.new(false, 16)
when 'mem32' then return Address.new(false, 32)
when 'mem64' then return Address.new(false, 64)
when 'mem80' then return Address.new(false, 80)
when 'memoffs8' then return Address.new(true, 8)
when 'memoffs16' then return Address.new(true, 16)
when 'memoffs32' then return Address.new(true, 32)
when 'fpureg' then return FPURegister.new
when /ST(.*)/ then return FPURegister.new(nil,$1.to_i)
when 'mmxreg' then return MMXRegister.new
when /MM(.*)/ then return MMXRegister.new(nil,nil,$1.to_i)
when 'CR0/2/3/4' then return ControlRegister.new
when 'DR0/1/2/3/6/7' then return DebugRegister.new
when 'TR3/4/5/6/7' then return TestRegister.new
else
warn "unknown parameter: #{parameter.inspect}"
return parameter
end
end
def initialize_parameters params
self.parameters = params.split(/,/).map { |s| self.to_parameter s }
end
def assemble instruction
stream = []
opcodes.each_with_index do |each, index|
self.execute_instruction_position_on(each, instruction,
(index + 1) / opcodes.size, stream)
end
stream
end
def execute_instruction_position_on(byte, instruction, position, stream)
case byte
when 'a16', 'a32' then
raise "not done yet"
when 'o16' then
return self.align16_on(instruction, stream)
when 'o32' then
return self.align32_on(instruction, stream)
when 'ib' then
return stream.push_B(instruction.get_immediate)
when 'iw' then
return stream.push_W(instruction.get_second_immediate) if position == 1
return stream.push_W(instruction.get_immediate)
when 'id' then
return stream.push_D(instruction.get_second_immediate) if position == 1
return stream.push_D(instruction.get_immediate)
when 'rb' then
return self.relative_b_on(instruction, stream)
when 'rw' then
return self.relative_w_on(instruction, stream)
when 'rw/rd' then
return self.relative_w_on(instruction, stream) if
instruction.machine.bits == 16
return self.relative_d_on(instruction, stream)
when 'rd' then
return self.relative_d_on(instruction, stream)
when 'ow' then
raise byte
# [^stream push_W: instruction get_address offset].
when 'od' then
raise byte
# [^stream push_D: instruction get_address offset].
when 'ow/od' then
if instruction.machine.bits == 16 then
stream.push_W instruction.get_address.offset
end
return stream.push_D(instruction.get_address.offset)
when /^\/(.*)/ then
return self.modrm_instruction_on($1, instruction, stream)
end
number = byte.hex
number += instruction.parameters[parameters.first.id ? 1 : 0].id if
byte =~ /r$/
stream << number
end
##
# If we get here, there will be at least two parameters to combine
# a memory address with a register or a register with a register"
def modrm_r_on instruction, stream
address, register = instruction.first, instruction.second
swap = false # TODO: this can be 1 call at the bottom
if instruction.first.is_a?(Register) && instruction.second.is_a?(Register) then
if parameters.first.is_a?(MemoryRegister) then
return instruction.first.push_mod_rm_on(instruction.second, stream)
else
return instruction.second.push_mod_rm_on(instruction.first, stream)
end
end
if instruction.first.is_a?(SpecialRegister) then
return instruction.second.push_mod_rm_on(instruction.first, stream)
end
if instruction.second.is_a?(SpecialRegister) then
return instruction.first.push_mod_rm_on(instruction.second, stream)
end
address, register = if instruction.first.is_a?(Register) && instruction.second.respond_to?(:push_mod_rm_on) then
[instruction.second, instruction.first]
else
[instruction.first, instruction.second]
end
address.push_mod_rm_on register, stream
end
def align16_on instruction, stream
stream << 0x66 if instruction.machine.bits != 16
end
def relative_x_on instruction, stream, msg, dist
offset = instruction.first
offset = offset.offset if offset.is_a?(Address) && offset.offset?
if offset.is_a? Label then
if (offset.is_a?(FutureLabel) && offset.position.nil? ) then
offset.add instruction.machine.stream.size
return stream.send(msg, dist)
end
offset = offset.position
end
stream.send(msg, -(instruction.machine.stream.size - offset + dist))
end
def relative_b_on instruction, stream
relative_x_on instruction, stream, :push_B, 2
end
def relative_d_on instruction, stream
relative_x_on instruction, stream, :push_D, 5
end
def relative_w_on instruction, stream
relative_x_on instruction, stream, :push_W, 3
end
def modrm_n_instruction_on id, instruction, stream
instruction.first.push_mod_rm_on Register.new(instruction.machine, id, instruction.first.bits), stream
end
def align32_on instruction, stream
stream << 0x67 if instruction.machine.bits != 32
end
def modrm_instruction_on byte, instruction, stream
if byte == "r" then
self.modrm_r_on instruction, stream
else
self.modrm_n_instruction_on byte.to_i, instruction, stream
end
end
end
end

View File

@ -0,0 +1,85 @@
require "fiddle"
class Integer
def m
address = Intel::Address.new
address.offset = self
address
end
def inspect
"0x#{to_s 16}"
end if $DEBUG
end
class Array
def second
self[1]
end
def push_D integer
self.push(*[integer].pack("V").unpack("C4"))
end
def push_B integer
self << (integer & 255)
end
def push_W integer
self.push((integer & 255), (integer >> 8 & 255))
end
end
ASM = []
class Object
def assemble arg_count = 0, &block
asm = Intel::MachineCodeX86.new
# TODO: enter?
asm.ebp.push
asm.ebp.mov asm.esp
size = asm.stream.size
asm.instance_eval(&block)
if asm.stream.size == size # return nil
warn "returning nil for #{self}##{name}"
asm.eax.mov 4
end
asm.leave
asm.ret
code = asm.stream.pack("C*")
if $DEBUG then
path = "#{$$}.obj"
File.open path, "wb" do |f|
f.write code
end
puts code.unpack("C*").map { |n| "%02X" % n }.join(' ')
system "ndisasm -u #{path}"
File.unlink path
end
code
end
@@asm = {}
def asm(name, *args, &block)
code = @@asm[name] ||= assemble(&block).to_ptr
return execute_asm(code) # code is the function pointer, wrapped
end
# defasm :execute_asm, :code do
# eax.mov ebp + 0x0c # grab code
# eax.mov eax + 0x10 # unwrap function pointer field
# eax.mov eax.m # dereference the pointer
# eax.call # call the function pointer
# end
end

20
lib/intel/immediate.rb Normal file
View File

@ -0,0 +1,20 @@
require 'intel/operand'
module Intel
##
# Immediate is an Integer wrapper so that we know the machine we're
# dealing with when we apply commands
class Immediate < Operand
attr_accessor :value
def initialize( bits = nil )
super(nil , bits)
end
def immediate?
true
end
end
end

59
lib/intel/instruction.rb Normal file
View File

@ -0,0 +1,59 @@
module Intel
##
# Instruction is an instruction shape that we're going to match to
# Commands to find out what we should write in to memory.
class Instruction
attr_accessor :opcode, :machine, :parameters
def initialize message, machine
self.machine = machine
self.opcode, *self.parameters = message
self.opcode = opcode.to_s.upcase
self.machine = parameters[1].machine unless machine
self.parameters.map! { |each| Proc === each ? each.call.m : each }
self.parameters.each do |each|
each.machine = self.machine if each.is_a? Operand
end
end
def first
parameters.first
end
def second
parameters.second
end
def get_address
parameters.detect { |e| e.is_a?(Address) }
end
def assemble
instructions = machine.instructions.select { |command|
command.instruction_applies? self
}
return false if instructions.empty?
bytes = instructions.map { |instruction| instruction.assemble self }
sorted_bytes = bytes.sort_by {|byte| [byte.size, (byte[0]||0), (byte[1]||0)]}
machine.stream.push(*sorted_bytes.first)
true
end
def get_second_immediate
parameters.detect { |e| e.is_a? Integer }
end
def get_immediate
parameters.reverse.detect { |e| e.is_a? Integer }
end
end
end

66
lib/intel/label.rb Normal file
View File

@ -0,0 +1,66 @@
module Intel
##
# Label is a known point in the byte stream that we can jmp/loop back to.
class Label < Operand
attr_accessor :position
def initialize machine , position = nil
super( machine)
@position = position
end
def bits
distance = machine.stream.size - position
if distance < 256 then
8
elsif distance < 65536 then
16
else
32
end
end
end
##
# FutureLabel is a label in memory that hasn't been defined yet and
# will go back and fill in the appropriate memory bytes later
class FutureLabel < Label
attr_accessor :positions
def initialize(machine)
super( machine )
self.positions = []
end
def plant
self.position = machine.stream.size
positions.each do |each|
size = machine.stream[each + 1]
address = []
case size
when 2 then
address.push_B(position - each - 2)
when 3 then
address.push_W(position - each - 3)
when 5 then
address.push_D(position - each - 5)
else
raise "unhandled size #{size}"
end
address.each_with_index do |byte, index|
idx = each + index + 1
machine.stream[idx] = byte
end
end
end
def add aPosition
positions << aPosition
end
end
end

View File

@ -0,0 +1,264 @@
module Intel
##
# MachineCodeX86 is a concrete implementation of a machine to create
# X86 assembly code on.
#
# To use this:
#
# a) you can instantiate an instance and use its register variables
# to build up machine code in the @stream variable and then use
# those bytes in any way that you see fit, or
#
#
# == Using MachineCodeX86 for scripting
#
# This is the long hand way of writing assembly code, since you
# always include a receiver with every command.
#
# asm = Assembler.MachineCodeX86.new
#
# Once you have an assembler, you can access the registers and send
# commands to them, eg:
#
# asm.eax.mov 1
#
# As you send the commands, the @stream will build up containing the
# X86 assembler bytes you can use. You can use memory addresses in
# your assembler code with the #m method, eg:
#
# asm.eax.m.mov 1
#
# Once you are finished, you simply send:
#
# asm.stream
#
# This will return you the stream of bytes.
#
# == Labels & Jumps
#
# You can do labels and jump to them using two different label
# commands. The first is #label, which places a label jump point
# immediately on call, eg:
#
# label = asm.label
# label.jmp
#
# The other is a future label that can be placed at some future
# point in the program and jumped too
#
# label = asm.future_label
# asm.eax.xor asm.eax
# label.jmp
# asm.eax.inc
# label.plant
#
# You #plant the future label where you want it to actually be and
# past references to it will be updated. Future labels will always
# use a dword jmp so that there's space to fill in the command if
# the jmp ends up being far.
class MachineCodeX86
attr_accessor :stream, :procedure, :bits, :cachedInstructions
attr_reader :processors
attr_writer :instructions
def initialize
self.procedure = nil
self.bits = self.defaultBits
self.processors = self.defaultProcessors
self.stream = []
self.setupMachine
end
def inspect
"#{self.class}#{stream.inspect}"
end
def processors= o
@processors = o
@cachedInstructions = nil
end
def supportsProcessor instructionProcessors
# TODO: can still be improved. hashes, caching... something
! (processors & instructionProcessors).empty?
end
def instructions
self.cachedInstructions ||= @instructions.select { |e|
self.supportsProcessor e.processors
}
self.cachedInstructions
end
def method_missing msg, *args
ok = Instruction.new( [msg, *args] , self).assemble
return super unless ok
ok
end
def label
Label.new(self, stream.size)
end
def future_label
FutureLabel.new self
end
def assemble instruction
raise "no"
# aBlock on: MessageNotUnderstood do: [:ex |
# ex originator class = BlockClosure ifFalse: [ex pass].
# ex resume: (ex originator value m perform: ex parameter selector withArguments: ex parameter arguments)]</body>
end
# registers-general-32bit
attr_accessor :eax, :ebx, :ebp, :esp, :edi, :esi, :ecx, :edx
# registers-fpu
attr_accessor :st0, :st1, :st2, :st3, :st4, :st5, :st6, :st7
# registers-debug
attr_accessor :dr0, :dr1, :dr2, :dr3, :dr6, :dr7
# registers-segment
attr_accessor :es, :ss, :cs, :gs, :fs, :ds
# registers-test
attr_accessor :tr3, :tr4, :tr5, :tr6, :tr7
# registers-general-8bit
attr_accessor :al, :ah, :bl, :bh, :cl, :ch, :dl, :dh
# registers-general-16bit
attr_accessor :ax, :bx, :cx, :dx, :sp, :bp, :si, :di
# registers-control
attr_accessor :cr0, :cr2, :cr3, :cr4
# registers-mmx
attr_accessor :mm0, :mm1, :mm2, :mm3, :mm4, :mm5, :mm6, :mm7
def setupFPURegisters
self.st0 = FPURegister.new self, 0
self.st1 = FPURegister.new self, 1
self.st2 = FPURegister.new self, 2
self.st3 = FPURegister.new self, 3
self.st4 = FPURegister.new self, 4
self.st5 = FPURegister.new self, 5
self.st6 = FPURegister.new self, 6
self.st7 = FPURegister.new self, 7
end
def setupControlRegisters
self.cr0 = ControlRegister.new self, 0
self.cr2 = ControlRegister.new self, 2
self.cr3 = ControlRegister.new self, 3
self.cr4 = ControlRegister.new self, 4
end
def platform
'i386'
end
def setupDebugRegisters
self.dr0 = DebugRegister.new self, 0
self.dr1 = DebugRegister.new self, 1
self.dr2 = DebugRegister.new self, 2
self.dr3 = DebugRegister.new self, 3
self.dr6 = DebugRegister.new self, 6
self.dr7 = DebugRegister.new self, 7
end
def defaultBits
32
end
def setupSegmentRegisters
self.es = SegmentRegister.new self, 0
self.cs = SegmentRegister.new self, 1
self.ss = SegmentRegister.new self, 2
self.ds = SegmentRegister.new self, 3
self.fs = SegmentRegister.new self, 4
self.gs = SegmentRegister.new self, 5
end
def defaultProcessors
%w(8086 186 286 386 486 PENT P6 CYRIX FPU MMX PRIV UNDOC)
end
def setupMachine
self.instructions = Assembler.commands
self.setup8BitRegisters
self.setup16BitRegisters
self.setup32BitRegisters
self.setupSegmentRegisters
self.setupControlRegisters
self.setupTestRegisters
self.setupDebugRegisters
self.setupFPURegisters
self.setupMMXRegisters
end
def setup8BitRegisters
self.al = Register.new self, 0, 8
self.cl = Register.new self, 1, 8
self.dl = Register.new self, 2, 8
self.bl = Register.new self, 3, 8
self.ah = Register.new self, 4, 8
self.ch = Register.new self, 5, 8
self.dh = Register.new self, 6, 8
self.bh = Register.new self, 7, 8
end
def setup16BitRegisters
self.ax = Register.new self, 0, 16
self.cx = Register.new self, 1, 16
self.dx = Register.new self, 2, 16
self.bx = Register.new self, 3, 16
self.sp = Register.new self, 4, 16
self.bp = Register.new self, 5, 16
self.si = Register.new self, 6, 16
self.di = Register.new self, 7, 16
end
def setupMMXRegisters
self.mm0 = MMXRegister.new self, 0
self.mm1 = MMXRegister.new self, 1
self.mm2 = MMXRegister.new self, 2
self.mm3 = MMXRegister.new self, 3
self.mm4 = MMXRegister.new self, 4
self.mm5 = MMXRegister.new self, 5
self.mm6 = MMXRegister.new self, 6
self.mm7 = MMXRegister.new self, 7
end
def setupTestRegisters
self.tr3 = TestRegister.new self, 3
self.tr4 = TestRegister.new self, 4
self.tr5 = TestRegister.new self, 5
self.tr6 = TestRegister.new self, 6
self.tr7 = TestRegister.new self, 7
end
def setup32BitRegisters
self.eax = Register.new self, 0, 32
self.ecx = Register.new self, 1, 32
self.edx = Register.new self, 2, 32
self.ebx = Register.new self, 3, 32
self.esp = Register.new self, 4, 32
self.ebp = Register.new self, 5, 32
self.esi = Register.new self, 6, 32
self.edi = Register.new self, 7, 32
end
def arg n
ebp + (n+3) * 4
end
end
end

27
lib/intel/operand.rb Normal file
View File

@ -0,0 +1,27 @@
require 'intel/instruction'
module Intel
##
# Operand is any kind of operand used in a command or instruction,
# eg: registers, memory addresses, labels, immediates, etc.
class Operand
attr_accessor :machine, :bits
def initialize machine = nil , bits = nil
@bits = bits
@machine = machine
end
def method_missing msg, *args, &b
ok = Instruction.new( [msg, self, *args] + (b ? [b] : []) , machine).assemble
return super unless ok
ok
end
def operand?
true
end
end
end

52
lib/intel/register.rb Normal file
View File

@ -0,0 +1,52 @@
module Intel
##
# Register is a general X86 register, such as eax, ebx, ecx, edx,
# etc...
class Register < Operand
attr_accessor :id
def initialize machine = nil, id = nil , bits = nil
super(machine, bits)
self.id = id
end
def get address # TODO: test
self.mov address
self.mov {self}
end
def push_mod_rm_on spareRegister, stream
stream << (0b11000000 + id + (spareRegister.id << 3))
end
def m
self + 0
end
def - offset
self + -offset
end
def + offset
address = Address.new
address.machine = machine
address.id = id
address.offset = offset
address
end
end
# MemoryRegister is a regular Register, but the parser needs to know
# if it is a primary or secondary register. This form is a private
# secondary register. Use Register instead of this guy.
class MemoryRegister < Register
def initialize bits
super(nil,nil,bits)
end
end
end

View File

@ -0,0 +1,57 @@
require 'intel/register'
require 'intel/operand'
module Intel
##
# SpecialRegister is the abstract implementation of any kind of
# register that isn't a general register, eg: segment registers, mmx
# registers, fpu registers, etc...
class SpecialRegister < Operand
attr_accessor :id
def initialize machine = nil, id = nil , bits = nil
super(machine,bits)
self.id = id
end
end
##
# DebugRegister is an X86 DRx register
class DebugRegister < SpecialRegister
end
##
# TestRegister is an X86 Test Register, TRx
class TestRegister < SpecialRegister
end
##
# FPURegister is an X86 fpureg, STx
class FPURegister < SpecialRegister
end
##
# ControlRegister is an X86 CRx register
class ControlRegister < SpecialRegister
end
##
# MMXRegister is an X86 MMX register
class MMXRegister < SpecialRegister
def push_mod_rm_on spareRegister, stream
stream << (0b11000000 + id + (spareRegister.id << 3))
end
end
##
# SegmentRegister is an X86 segment register, eg: ss, cs, ds, es...
class SegmentRegister < SpecialRegister
end
end

3
lib/intel/versions.rb Normal file
View File

@ -0,0 +1,3 @@
module Intel
VERSION = '1.1.1'
end

602
test/test_intel.rb Normal file
View File

@ -0,0 +1,602 @@
require_relative 'helper'
require 'intel/all'
class TestIntel < MiniTest::Unit::TestCase
# MachineCodeX86Test initialize-release
def setup
@asm = Intel::MachineCodeX86.new
@stream = asm.stream
end
attr_reader :asm, :stream
def ttest_wtf_inline! #Fiddle disabled
assert_equal 1000, X.new.counter
end
def ttest_wtf1? #Fiddle disabled
assert_equal 42, add_to_n(41)
end
def ttest_wtf2? #Fiddle disabled
assert_equal 42, passthrough(42)
end
# MachineCodeX86Test testing ow/od
def test_mov_offset_eax
256.m.mov asm.eax
assert_equal [0xA3, 0, 1, 0, 0], stream
end
def test_mov_eax_offset
asm.eax.mov 256.m
assert_equal [0xA1, 0, 1, 0, 0], stream
end
# MachineCodeX86Test testing reg<32, mem
def test_mov_al_big_offset
asm.al.mov 256.m
assert_equal [0xA0, 0, 1, 0, 0], stream
end
def test_mov_cl_m_edx
asm.cl.mov asm.edx.m
assert_equal [0x8A, 0b00001010], stream
end
def test_mov_ax_m_ecx
asm.ax.mov asm.ecx.m
assert_equal [0x66, 0x8B, 1], stream
end
def test_mov_cl_offset
asm.cl.mov 1.m
assert_equal [0x8A, 0x0D, 1, 0, 0, 0], stream
end
def test_mov_ax_big_offset
asm.ax.mov 256.m
assert_equal [0x66, 0xA1, 0, 1, 0, 0], stream
end
def test_mov_al_offset
asm.al.mov 1.m
assert_equal [0xA0, 1, 0, 0, 0], stream
end
def test_mov_cx_offset
asm.cx.mov 1.m
assert_equal [0x66, 0x8B, 0x0D, 1, 0, 0, 0], stream
end
def test_mov_cx_m_edx
asm.cx.mov asm.edx.m
assert_equal [0x66, 0x8B, 0b00001010], stream
end
def test_mov_ax_offset
asm.ax.mov 1.m
assert_equal [0x66, 0xA1, 1, 0, 0, 0], stream
end
def test_mov_al_m_ecx
asm.al.mov asm.ecx.m
assert_equal [0x8A, 1], stream
end
# MachineCodeX86Test testing /r reg/reg
def test_mov_eax_ebx
asm.eax.mov asm.ebx
assert_equal [0x89, 0b11011000], stream
end
def test_mov_ebx_ecx
asm.ebx.mov asm.ecx
assert_equal [0x89, 0b11001011], stream
end
# MachineCodeX86Test testing /n reg
def test_bt_ecx_literal
asm.ecx.bt 1
assert_equal [0x0F, 0xBA, 0b11100001, 1], stream
end
def test_fdivr
asm.ecx.m.fdivr
assert_equal [0xD8, 0b00000001], stream
end
# MachineCodeX86Test testing []
def test_bracket_argument
asm.eax.mov { asm.ecx }
assert_equal [0x8B, 1], stream
end
# def test_bracket_receiver # HACK
# asm.assemble { [asm.ecx].mov asm.eax }
# assert_equal [0x89, 1], stream
# end
# MachineCodeX86Test testing ib/iw/id
def test_add_eax_literal
asm.eax.add 256
assert_equal [5, 0, 1, 0, 0], stream
end
def test_add_ax_literal
asm.ax.add 256
assert_equal [0x66, 5, 0, 1], stream
end
def test_add_al_literal
asm.al.add 1
assert_equal [4, 1], stream
end
# MachineCodeX86Test testing rb/rw/rd
def test_label_jmp_veryFar
label = asm.label
65536.times { asm.stream << 0x90 } # cheaters way to do nop, so it runs faster
label.jmp
assert_equal 65536 + 5, stream.size
assert_equal [0xE9, 0xFB, 0xFF, 0xFE, 0xFF], stream[65536..-1]
end
def test_jmp_big_offset
asm.jmp 256.m
assert_equal [0xFF, 0b00100101, 0, 1, 0, 0], stream
end
def test_jmp_m_ecx
asm.jmp asm.ecx.m
assert_equal [0xFF, 0b00100001], stream
end
def test_jmp_infinite
label = asm.label
label.jmp
assert_equal [0xEB, 0xFE], stream
end
def test_label_jmp_far
asm.bits = 16
label = asm.label
256.times { stream << 0x90 } # cheaters way to do nop, so it runs faster
label.jmp
assert_equal 256 + 3, stream.size
assert_equal [0xE9, 0xFD, 0xFE], stream[256..-1]
end
def test_jmp_forward_and_backward
label = asm.future_label
label.jmp
asm.nop
label.plant
label.jmp
assert_equal [0xE9, 1, 0, 0, 0, 0x90, 0xEB, 0xFE], stream
end
def test_jmp_forward
label = asm.future_label
label.jmp
asm.nop
label.plant
assert_equal [0xE9, 1, 0, 0, 0, 0x90], stream
end
def test_jmp_offset
asm.jmp 1.m
assert_equal [0xFF, 0b00100101, 1, 0, 0, 0], stream
end
def test_jmp_far
asm.jmp 256
assert_equal [0xE9, 0xFB, 0, 0, 0], stream
end
def test_loop_infinite
label = asm.label
label.loop
assert_equal [0xE2, 0xFE], stream
end
# MachineCodeX86Test testing o16/o32
def test_adc_ax_literal
asm.bits = 32
asm.ax.add 1
assert_equal [0x66, 5, 1, 0], stream
end
def test_adc_ax_literal16
asm.bits = 32
asm.ax.add 256
assert_equal [0x66, 5, 0, 1], stream
end
def test_adc_eax_literal
asm.bits = 16
asm.eax.add 1
assert_equal [0x67, 0x83, 0b11000000, 1], stream
end
def test_adc_eax_literal16
asm.bits = 16
asm.eax.add 256
assert_equal [0x67, 5, 0, 1, 0, 0], stream
end
# MachineCodeX86Test testing cpuregs
def test_mov_ecx_cr0
asm.ecx.mov asm.cr0
assert_equal [0x0f, 0x20, 0b11000001], stream
end
def test_mov_dr0Ecx
asm.dr0.mov asm.ecx
assert_equal [0x0f, 0x23, 0b11000001], stream
end
def test_mov_ecx_tr3
asm.ecx.mov asm.tr3
assert_equal [0x0f, 0x24, 0b11011001], stream
end
def test_mov_tr3_ecx
asm.tr3.mov asm.ecx
assert_equal [0x0f, 0x26, 0b11011001], stream
end
def test_mov_ecx_dr0
asm.ecx.mov asm.dr0
assert_equal [0x0f, 0x21, 0b11000001], stream
end
def test_mov_cr0_ecx
asm.cr0.mov asm.ecx
assert_equal [0x0f, 0x22, 0b11000001], stream
end
# MachineCodeX86Test testing /r reg/mem
def test_mov_eax_m_ecx
asm.eax.mov asm.ecx.m
assert_equal [0x8B, 0b00000001], stream
end
def test_mov_ebx_m_ecx_edx_offset
asm.ebx.mov(asm.ecx + asm.edx + 1)
assert_equal [0x8B, 0b00011100, 0b01010001, 1], stream
end
def test_mov_ebx_m_ecx_edx
asm.ebx.mov(asm.ecx + asm.edx)
assert_equal [0x8B, 0b00011100, 0b00010001], stream
end
def test_mov_ebx_m_ecx_edx_big_offset
asm.ebx.mov(asm.ecx + asm.edx + 256)
assert_equal [0x8B, 0b00011100, 0b10010001, 0, 1, 0, 0], stream
end
def test_mov_eax_m_ecx_big_offset
asm.eax.mov asm.ecx + 256
assert_equal [0x8B, 0b10000001, 0, 1, 0, 0], stream
end
def test_mov_ecx_m_offset
asm.ecx.mov 256.m
assert_equal [0x8B, 0x0D, 0, 1, 0, 0], stream
end
def test_mov_eax_m_ecx_offset
asm.eax.mov asm.ecx + 1
assert_equal [0x8B, 0b01000001, 1], stream
end
# MachineCodeX86Test testing imm:imm
def test_jmp_imm_Imm32
asm.jmp 256, 65537
assert_equal [0xEA, 1, 0, 1, 0, 0, 1], stream
end
def test_call_imm_Imm16
asm.call 1, 2
assert_equal [0x66, 0x9A, 2, 0, 1, 0], stream
end
def test_jmp_imm_Imm16
asm.jmp 1, 2
assert_equal [0x66, 0xEA, 2, 0, 1, 0], stream
end
def test_call_imm_Imm32
asm.call 256, 65537
assert_equal [0x9A, 1, 0, 1, 0, 0, 1], stream
end
# MachineCodeX86Test testing 0 args
def test_ret
asm.ret
assert_equal [0xC3], stream
end
def test_nop
asm.nop
assert_equal [0x90], stream
end
def test_hlt
asm.hlt
assert_equal [0xF4], stream
end
# MachineCodeX86Test testing 3 args
def test_imul_ecx_edx_immediate
asm.ecx.imul asm.edx, 1
assert_equal [0x6B, 0xCA, 1], stream
end
def test_imul_ecx_edx_big_immediate
asm.ecx.imul asm.edx, 256
assert_equal [0x69, 0xCA, 0, 1, 0, 0], stream
end
# MachineCodeX86Test testing fpureg
def test_fadd_st0St1
asm.st0.fadd asm.st1
assert_equal [0xD8, 0xC1], stream
end
def test_fmulp_st1St0
asm.st1.fmulp asm.st0
assert_equal [0xDE, 0xC9], stream
end
def test_fadd_st0
asm.st0.fadd
assert_equal [0xD8, 0xC0], stream
end
def test_fadd_st1
asm.st1.fadd
assert_equal [0xD8, 0xC1], stream
end
# MachineCodeX86Test testing /n mem
def test_fild_m_ecx_edx_offset
(asm.ecx + asm.edx + 1).fild
assert_equal [0xDB, 0b00000100, 0b01010001, 1], stream
end
def test_bt_m_ecx_literal
# ... this shouldn't work. The machine code generated here does
# not work and nasm complains that a size was not specified if you
# try to write the same code in nasm -> mov [ecx], 1
#
# Some how we're meant to know this is invalid and throw an
# error.. not sure how yet.
asm.ecx.m.bt 1
assert_equal [0x0F, 0xBA, 0b00100001, 1], stream
end
def test_fild_m_ecx_big_offset
(asm.ecx + 256).fild
assert_equal [0xDB, 0b10000001, 0, 1, 0, 0], stream
end
def test_fild_m_ecx_edx
(asm.ecx + asm.edx).fild
assert_equal [0xDB, 0b00000100, 0b00010001], stream
end
def test_fild_m_ecx_edx_big_offset
(asm.ecx + asm.edx + 256).fild
assert_equal [0xDB, 0b00000100, 0b10010001, 0, 1, 0, 0], stream
end
def test_fild_m_ecx
asm.ecx.m.fild
assert_equal [0xDB, 0b00000001], stream
end
def test_fild_m_ecx_offset
(asm.ecx + 1).fild
assert_equal [0xDB, 0b01000001, 1], stream
end
# MachineCodeX86Test testing processors
# def testing_adc_edx_ecx # HACK
# asm.processors.reject! { |processor| processor == '386' }
# assert_raise NoMethodError do
# asm.edx.adc asm.ecx
# end
# end
# MachineCodeX86Test testing mmxreg
def test_psllw_mm1Immediate
asm.mm1.psllw 1
assert_equal [0x0F, 0x71, 0xF1, 1], stream
end
def test_movd_eax_mm0
asm.eax.movd asm.mm0
assert_equal [0x0F, 0x7E, 0xC0], stream
end
def test_movd_mm0Eax
asm.mm0.movd asm.eax
assert_equal [0x0F, 0x6E, 0xC0], stream
end
# MachineCodeX86Test testing +r
def test_mov_ecx_literal
asm.ecx.mov 1
assert_equal [0xB9, 1, 0, 0, 0], stream
end
def test_mov_edx_literal
asm.edx.mov 1
assert_equal [0xBA, 1, 0, 0, 0], stream
end
def test_mov_eax_literal
asm.eax.mov 1
assert_equal [0xB8, 1, 0, 0, 0], stream
end
def test_mov_ebx_literal
asm.ebx.mov 1
assert_equal [0xBB, 1, 0, 0, 0], stream
end
# MachineCodeX86Test testing /r mem/reg
def test_mov_m_ecx_edx_offset_ebx
(asm.ecx + asm.edx + 1).mov asm.ebx
assert_equal [0x89, 0b00011100, 0b01010001, 1], stream
end
def test_mov_m_eax_ecx
asm.eax.m.mov asm.ecx
assert_equal [0x89, 0b00001000], stream
end
def test_mov_m_ecx_big_offset_ebx
(asm.ecx + 256).mov asm.ebx
assert_equal [0x89, 0b10011001, 0, 1, 0, 0], stream
end
def test_mov_m_ecx_edx_big_offset_ebx
(asm.ecx + asm.edx + 256).mov asm.ebx
assert_equal [0x89, 0b00011100, 0b10010001, 0, 1, 0, 0], stream
end
def test_mov_m_ecx_offset_ebx
(asm.ecx + 1).mov asm.ebx
assert_equal [0x89, 0b01011001, 1], stream
end
def test_mov_m_ecx_eax
asm.ecx.m.mov asm.eax
assert_equal [0x89, 0b00000001], stream
end
def test_mov_m_ecx_edx_ebx
(asm.ecx + asm.edx).mov asm.ebx
assert_equal [0x89, 0b00011100, 0b00010001], stream
end
# MachineCodeX86Test testing +cc
def test_cmovne_eax_ecx
asm.eax.cmovne asm.ecx
assert_equal [0x0F, 0x45, 0xC1], stream
end
def test_cmove_eax_ecx
asm.eax.cmove asm.ecx
assert_equal [0x0F, 0x44, 0xC1], stream
end
def test_jnb
asm.label.jnb
assert_equal [0x73, 0xFE], stream
end
def test_jnc
asm.label.jnc
assert_equal [0x73, 0xFE], stream
end
def test_jno
asm.label.jno
assert_equal [0x71, 0xFE], stream
end
def test_jae
asm.label.jae
assert_equal [0x73, 0xFE], stream
end
def test_jnae
asm.label.jnae
assert_equal [0x72, 0xFE], stream
end
def test_cmovz_eax_ecx
asm.eax.cmovz asm.ecx
assert_equal [0x0F, 0x44, 0xC1], stream
end
def test_jb
asm.label.jb
assert_equal [0x72, 0xFE], stream
end
def test_jc
asm.label.jc
assert_equal [0x72, 0xFE], stream
end
def test_cmovnz_eax_ecx
asm.eax.cmovnz asm.ecx
assert_equal [0x0F, 0x45, 0xC1], stream
end
def test_jo
asm.label.jo
assert_equal [0x70, 0xFE], stream
end
# MachineCodeX86Test testing reg,1/cl
def test_rcr_eax1
asm.eax.rcr 1
assert_equal [0xD1, 0xD8], stream
end
def test_rcr_eaxCl
asm.eax.rcr asm.cl
assert_equal [0xD3, 0xD8], stream
end
# MachineCodeX86Test testing segreg
def test_mov_fs_m_eax
asm.fs.mov asm.eax.m
assert_equal [0x8E, 0x20], stream
end
def test_mov_eaxFs
asm.eax.mov asm.fs
assert_equal [0x8C, 0xE0], stream
end
def test_mov_m_eaxFs
asm.eax.m.mov asm.fs
assert_equal [0x8C, 0x20], stream
end
def test_mov_fs_eax
asm.fs.mov asm.eax
assert_equal [0x8E, 0xE0], stream
end
end