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Compiler Construction/Intermediate Representation
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Intermediate Representation
The form of the internal representation among different compilers varies widely. If the back end is called as a subroutine by the front end then the intermediate representation is likely to be some form of annotated parse tree, possibly with supplementary tables.
If the back end operates as a separate program then the intermediate representation is likely to be some low-level pseudo assembly language or some register transfer language (it could be just numbers, but debugging is easier if it is human-readable).
Low-Level Pseudo Code
Complete
Annotated Parse Tree
Complete