Building a
compiler is more than translating high-level programming languages to assembly
or machine code. A compiler is an instance of translators from a source
language to a target language.
In this
document it is explained that we have the same structure in many translators:
an input sting which is composed into tokens, these tokens are grouped into
phrases and then these phrases are mapped to the output sequence determined by
the structure a context in which they occur.
We also
learn that compiler development tools, like lex and yacc, can be applied for
many translation problems.
It is explained
that Dot is a tool that reads a textual graph and produces a drawing of the
graph specified. To do something like this, the following actions are needed:
1- Read the textual graph using context-free
parsing techniques
2- Check semantic consistencies between
components
3- Construct internal representation
4- Determine the output
5- Modify the output
6- Generate postscript for the graph
For
translating Latex to html the translation should follow the following actions:
1- Read the latex document using context-free
parsing techniques
2- Construct internal representation
3- Process Latex constructs and output
We notice that the steps are less than the graph
example, and it is because the source and target languages are semantically much
closer in the Latex to html case.
Essentially, with both cases we can see the
same main phases of the compiler. A lexical analysis and parsing, A semantic
analysis, code generation and code optimization.
In Lexical analysis and parsing, the compiler refers
to the type or scope of a variable. In code Generation, the compiler transverse
the tree representation of a program to generate assembly or machine code for
the target machine. In optimization step, the compiler basically makes code transformations
to make the program faster.
