Compilers

In an interpreted language, we have a hard to program machine M₁. For example, maybe M₁ only takes Assembly. We write a program to simulate an easier to program machine M₂. Commands are given to the program which interprets the commands.

In a compiled language, we write programs for M₂, which are compiled into equivalent programs for M₁.

For example, an interpreter for Pascal, written in Python may:

• Parse programs using recursive descent into Abstract Syntax Trees
• Use an interpreter to evaluate these trees
• Store and load variables in a symbol table. Scopes are handled by a scoped symbol table
• To handle procedure calls, keep a stack of activation records

• 2017 6.004 compiler slides
• Blog post on building a compiler