Compiler

Optimizing compiler for a simple programming language smpl emitting machine code for DLX (MIPS) architecture.

Grammar

EBNF grammar for the smpl language below:

letter =  "a" | "b" | ... | "z".
digit =  "0" | "1" | ... | "9".
relOp  =  "==" | "!=" | "<" | "<=" | ">" | "=".
ident  =  letter {letter | digit}.
number  =  digit {digit}.
designator  = ident{ "[" expression "]" }.
factor  =  designator |  number  |  "(" expression ")"  | funcCall1.
term  =  factor { ("*" | "/") factor}.
expression  =  term {("+" | "-") term}.
relation  =  expression relOp expression .
assignment  =  "let" designator "<-" expression.
funcCall  =  "call" ident [2"(" [expression { "," expression } ] ")" ].
ifStatement  =  "if" relation "then" statSequence [ "else" statSequence ] "fi".
whileStatement  =  "while" relation "do" StatSequence "od".
returnStatement  =  "return" [ expression ].
statement  =  assignment | funcCall3| ifStatement | whileStatement | returnStatement.
statSequence  =  statement { ";" statement }[ ";"]4.
typeDecl  =  "var" | "array" "[" number "]" { "[" number "]" }.
varDecl  =  typeDecl indent { "," ident } ";".
funcDecl  =  [ "void" ] "function" ident formalParam ";" funcBody ";".
formalParam  = "(" [ident { "," ident }] ")".
funcBody  =  { varDecl } "{" [ statSequence ] "}".
computation  =  "main" { varDecl } { funcDecl } "{" statSequence "}" "."

TODO

• letter = "a" | "b" | ... | "z".

• digit = "0" | "1" | ... | "9".

• relOp = "==" | "!=" | "<" | "<=" | ">" | "=".

• ident = letter {letter | digit}.

• number = digit {digit}.

• designator = ident{ "[" expression "]" }.

• factor = designator | number | "(" expression ")" | funcCall1.

• term = factor { ("*" | "/") factor}.

• expression = term {("+" | "-") term}.

• relation = expression relOp expression .

• assignment = "let" designator "<-" expression.

• funcCall = "call" ident [2"(" [expression { "," expression } ] ")" ].

• ifStatement = "if" relation "then" statSequence [ "else" statSequence ] "fi".

• whileStatement = "while" relation "do" StatSequence "od".

• returnStatement = "return" [ expression ].

• statement = assignment | funcCall3| ifStatement | whileStatement | returnStatement.

• statSequence = statement { ";" statement }[ ";"]4.

• typeDecl = "var" | "array" "[" number "]" { "[" number "]" }.

• varDecl = typeDecl indent { "," ident } ";".

• funcDecl = [ "void" ] "function" ident formalParam ";" funcBody ";".

• formalParam = "(" [ident { "," ident }] ")".

• funcBody = { varDecl } "{" [ statSequence ] "}".

• computation = "main" { varDecl } { funcDecl } "{" statSequence "}" "."

• a compiler using the register set as a stack

• a sophisticated compiler propagating state up and down the parse tree

• static single assignment

• static single assignment while parsing

• common subexpression elimination

• aliasing with arrays

• register allocation

• instruction scheduling

• trace scheduling

• trace based just-in-time compilation

• object-oriented language features

• implementing functions