1.2.2 Applications generation Flashcards

Question

Translators What is a translator?

Answer 1

Any program which converts source code into machine code

Answer 2

Converts high level language into machine code Has a 1-to-many relationship, each line of source code translates into many lines of binary machine code Translates each line at a time

Answer 3

Converts high level languages into object/machine code Has a 1-to-many relationship where each line of high level source code translates into many lines of machine code Translates the entire program at once Object code is a part way between high level language code and machine code

Answer 4

Converts low level assembly language into machine code A 1-to-1 relationship usually, where each assembly code line translates into machine code

Answer 5

Drawbacks: Requires access to the whole source code when translating Executes slowly

Answer 6

Assembly code is not very portable across different systems, as it is processor specific

Answer 7

Lexical analysis Syntax analysis Code generation

Answer 8

* Removes non-program elements, such as white space and comments * Assigns tokens to individual parts (lexemes) of the source code * Code optimisation occurs

Answer 9

* Checks the tokens are in the correct order and that they follow the rules of the language * An Abstract Syntax Tree (AST) is created to map the structure of the program * Tokens that are missing or in the wrong place are reported

Answer 10

* A separate program is created, this is the object code * Object code is the executable binary equivalent of the source code * Code optimisation occurs

Answer 11

Carried out in the lexical analysis and code generation stages of compilation: Identifies redundant or repeated code and removes or rearranges as necessary

Answer 12

It reports them back as error messages added to the compiler report to the user, which contains the type of error and its location in the program

Answer 13

High level languages have pre-written libraries These give you access to may specialised functions Using libraries saves time as you don't have to keep rewriting the code contained in one, thus is more reliable and efficient

Answer 14

Compilation often results with multiple Object Code files A linker uses these to create a single executable file

Answer 15

Loads the executable code into RAM, so that the file can be executed Carries out other tasks to prepare a program for execution

Answer 16

* Programs are faster and more memory efficient * Provides direct manipulation of computer registers and storage * Can directly communicate with hardware devices * Can manipulate individual bits * Occupies less memory space and runs faster

Answer 17

* Low level languages are machine dependant, and therefore are not portable * More error-prone than high level languages * The programmer must have additional knowledge of computer architecture to write the code effectively * Harder for programmers to understand and learn

Answer 18

* Easier to write than low level languages * Less error-prone, and therefore easier to debug * Quicker and easier to write programs * Easier to debug and maintain

Answer 19

* Takes additional translation time * Cannot allow programmers to communicate directly with hardware * Generally less memory efficient than low level languages

Answer 20

* This is the half-way point in compilation between source code and machine code * It is the version of the code which is non-machine dependant, therefore can be copied to other devices and run on any computer * Is an important part of implementing virtual machines * A main benefit of intermediate code is it allows code to be stored part-compiled, so can be easily run later without requiring a compiler to be present