machine code


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Related to machine code: machine language, Assembly code

machine code

, language
instructions for the processing of data in a binary, octal, or hexadecimal code that can be understood and executed by a computer

machine code

[mə′shēn ‚kōd]
(computer science)
A computer representation of a character, digit, or action command in internal form.
A computer instruction in internal format, or that part of the instruction which identifies the action to be performed.
The set of all instruction types that a particular computer can execute.

machine code

The representation of a computer program which is actually read and interpreted by the computer. A program in machine code consists of a sequence of machine instructions (possibly interspersed with data). Instructions are binary strings which may be either all the same size (e.g. one 32-bit word for many modern RISC microprocessors) or of different sizes, in which case the size of the instruction is determined from the first word (e.g. Motorola 68000) or byte (e.g. Inmos transputer). The collection of all possible instructions for a particular computer is known as its "instruction set".

Execution of machine code may either be hard-wired into the central processing unit or it may be controlled by microcode. The basic execution cycle consists of fetching the next instruction from main memory, decoding it (determining which operation it specifies and the location of any arguments) and executing it by opening various gates (e.g. to allow data to flow from main memory into a CPU register) and enabling functional units (e.g. signalling to the ALU to perform an addition).

Humans almost never write programs directly in machine code. Instead, they use a programming language which is translated by the computer into machine code. The simplest kind of programming language is assembly language which usually has a one-to-one correspondence with the resulting machine code instructions but allows the use of mnemonics (ASCII strings) for the "op codes" (the part of the instruction which encodes the basic type of operation to perform) and names for locations in the program (branch labels) and for variables and constants.

machine code

The binary instructions a CPU executes. See machine language.
References in periodicals archive ?
As explained in the introduction, the machine code at the binary level, i.e.
We do not address such exploitation scenarios due to the lack of real valid machine code in the attacking traffic.
(74.) See Wikipedia, "Machine Code", archived at http://www.webcitation.org/5YFgyRfO 1.
Code consumers simulate the virtual machine by interpreting the transmitted intermediate representation or by compiling it into equivalent machine code. Most often the virtual machine utilizes a stack-based architecture.
So, various "higher-level" languages have been invented over the years: languages that look a lot more like a human language, but are still structured so they can be translated into machine code by a program called a compiler.
IBM resells INRANGE's complete line of FC/9000 Fibre Channel Directors under the IBM machine code 2042.
JbedME is an order of magnitude faster than standard J2ME implementations because it fully compiles Java bytecode into optimised machine code on the device itself.
Their mold making suppliers can then directly translate the machine code into CNC routines on the shop floor, to produce molds more efficiently and at lower cost to customers.
He was "addicted," as he put it, to machine code, the most unevolved (not to say barbaric) and certainly the most demanding of all computer languages, the use of which requires familiarity with the hardware foibles of one's particular machine.
An exploit uses known vulnerabilities in applications or operating systems to execute a program or code; it "exploits" a feature of a program or the operating system for its own use, such as to execute arbitrary machine code, read/write files on the hard disk, or gain illicit access.
Titan monitors all server requests via HTTP for suspicious query formats, such as hi-bit machine code instructions.
Another technique to execute Java programs is with a compiler that translates the Java bytecodes into native machine code. Like traditional high-level language compilers, a direct Java compiler starts with an application's Java source code (or, alternatively, with its bytecode) and translates it directly into the machine language of the target processor.