Assignment for my front-end compilers class A.Y. 2023-2024

Objective

Create a front-end compiler for Kaleidoscope extending the skeleton template from a modified version of the code from My First Language Frontend with LLVM Tutorial.

The assignment is divided in 4 parts, each one giving you a grammar and reuqiring the implementation of it and of the necessaries AST nodes.

First level grammar

Fisrt part requires to implement assignment logic for variables.

Grammar

% start startsymb;

startsymb:
	program 

program:
	% empty
| top ";" program % left ":";

top:
	% empty
| definition
|	external
| globalvar

definition:
	"def" proto block

external:
	"extern" proto

proto:
	"id" "(" idseq ")"

globalvar :
" global " "id"

idseq :
	% empty
|	"id" idseq

%left ":";
%left " <" "==";
%left "+" " -";
%left "*" "/";

stmts :
	stmt
|	stmt ";" stmts

stmt :
	assignment
|	block
|	exp

assignment
	"id" "=" exp

block:
	"{" stmts "}"
|	"{" vardefs ";" stmts "}"

vardefs:
	binding
| vardefs ";" binding

binding:
	"var" "id" initexp

exp:
	exp "+" exp
| exp " -" exp
| exp "*" exp
| exp "/" exp
| idexp
| "(" exp ")"
| "number"
| expif

initexp:
	%empty
| "=" exp

expif:
 	condexp "?" exp ":" exp

condexp:
	exp "<" exp
|	exp "==" exp

idexp:
	"id"
|	"id" "(" optexp ")"

optexp:
	%empty
|	explist

explist:
	exp
| exp "," explist

Second level grammar

Implements rules and logic for if construct, for loops and initializations.

stmt:
	assignment
| block
| ifstmt
| forstmt
| exp

ifstmt:
	"if" "(" condexp ")" stmt
| "if" "(" condexp ")" stmt " else " stmt

forstmt:
	"for" "(" init ";" condexp ";" assignment ")" stmt

init:
	binding
| assignment

Third level grammar

Implements boolean operators and, or and not for consecutive conditional expressions.

condexp:
	relexp
| relexp "and" condexp
| relexp "or" condexp
| "not" condexp
| "(" condexp ")"

relexp:
	exp "<" exp
| exp "==" exp

Fourth level grammar

TODO

binding:
	"var" "id" initexp
| "var" "id" "[" "number" "]"
| "var" "id" "[" "number" "]" "=" "{" explist "}"

idexp:
	"id"
|	"id" "(" optexp ")"
|	"id" "[" exp "]"

assignment:
	"id" "=" exp
|	"id" "[" exp "]" "=" exp