Writing a C Compiler

A flow chart shows the stages of the compiler, including a new optimization stage.

1. The lexer turns program.c into a token list.

2. The parser turns the token list into an abstract syntax tree.

3. Semantic analysis turns the AST into a transformed AST. It has three steps:

a. Identifier resolution

b. Type checking

c. Loop Labeling

4. TACKY Generation turns the transformed AST into TACKY.

5. Optimization (a new stage) turns TACKY into optimized TACKY. It has four steps:

a. Constant Folding

b. Unreachable Code Elimination

c. Copy Propagation

d. Dead Store Elimination

An arrow leads from each step to the next. Another arrow leads from dead store elimination back to constant folding.

6. Assembly generation turns optimized TACKY into assembly. ...