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How far to go ?

We do not expect a full grammar.

  1. The RTL Template is again RTL code that actually represents a given input source; in other words it is the IR! It has its own syntax, although it is true that the basic style is Lisp-like. We refer to this part of RTL that is used to write the RTL template as the code RTL. Using the KEY associated with an AST node type, GCC replaces the AST node by the RTL template5 to obtain an IR of a given input program.
  2. Code RTL grammar must be extracted for C language levels 0 and 1. We may extend it to levels 2 or 3, if required.
  3. There is a third form of RTL that is used in RTL dumps, which has been called RTL IR in section 2.2. This dump is a textual representation of the internal linked list of code RTL IR of the given input source. Its syntax is different and we are not required to extract its grammar.


next up previous
Next: About this document ... Up: Project on Machine Description Previous: The Problem
2006-01-08