Interpreters Execute the source program immediately rather than generating object code Examples: BASIC, LISP, used often in educational or development situations Speed of execution is slower than compiled code by a factor of 10 or more Share many of their operations with compilers
Interpreters • Execute the source program immediately rather than generating object code • Examples: BASIC, LISP, used often in educational or development situations • Speed of execution is slower than compiled code by a factor of 10 or more • Share many of their operations with compilers
A assemblers a translator for the assembly language of a particular computer Assembly language is a symbolic form of one machine language a compiler may generate assembly language as its target language and an assembler finished the translation into object code
Assemblers • A translator for the assembly language of a particular computer • Assembly language is a symbolic form of one machine language • A compiler may generate assembly language as its target language and an assembler finished the translation into object code
Linkers Collect separate object files into a directly executable file Connect an object program to the code for standard library functions and to resource supplied by OS Becoming one of the principle activities of a compiler, depends on Os and processor
Linkers • Collect separate object files into a directly executable file • Connect an object program to the code for standard library functions and to resource supplied by OS • Becoming one of the principle activities of a compiler, depends on OS and processor
Loaders Resolve all re-ocatable address relative to a given base Make executable code more flexible Often as part of the operating environment rarely as an actual separate program
Loaders • Resolve all re-locatable address relative to a given base • Make executable code more flexible • Often as part of the operating environment, rarely as an actual separate program
Preprocessors Delete comments include other files and perform macro substitutions Required by a language(as in C)or can be later add-ons that provide additional faciities
Preprocessors • Delete comments, include other files, and perform macro substitutions • Required by a language (as in C) or can be later add-ons that provide additional facilities