Abstract Syntax Tree For Loop

Model of an entire program or a certain program structure eg a statement or an expression in a java program an ast is abstract in the sense that some of the actual characters used in the concrete program text do not appear in the ast.

Abstract syntax tree for loop. Each node of the tree denotes a construct occurring in the source code. Abstract syntax trees are created no differently from other trees. As a verilog hdl complier odin ii should support for loop statements. If c then else loop the code this syntax extension could be written like this see the detail of syntax in the chapter about extensible grammars and the syntax tree quotations in the chapter about them.

A for loop is an important statement in verilog. Abstract syntax tree ast is a. An example is binary expressions like 1 2 a simple expression like that would create a single root node holding a right and left node that holds the data about the numbers. For instance grouping parentheses are implicit in the tree structure so these do.

There are a lot of tools available for this but to me it has always seemed a little bit too much work to get the tools together in a net project and generate a parser and do whatever else is needed. The more true statement in this case is that syntax tree nodes have a variadic amount of nodes as needed. Abstract syntax tree an. Moreover in order to optimize the circuit and make it more efficient odin ii should prune the abstract syntax tree ast before creating the netlist.

While the ast does allow us to generate slightly better and smaller instruction sequences in some cases eg. Syntax tree normally when you hear the term syntax tree you can assume people are talking about an abstract syntax tree. The project involves modifying the ast of for loops to support netlist. For for loops the practical impact is not worth mentioning.

Loop where rec loop do x. The abstract syntax tree has little impact on runtime performance or memory usage. Concrete syntax tree this is a more formal version of our abstract syntax tree and would include representations of literally everything written in the source file parentheses semicolons the lot. The syntax is abstract in the sense that it does not represent every detail appearing in the real syntax but rather just the structural or content related details.