Benjamin Gavin
cs 536
Section 1
Handout "Example for CSX-Lite"

*****  ATTENTION  *****
  This should be printed with a fixed width printer font, i.e.
  CS laser printers (using print or lpr), I cannot guarantee
  it will look right with a variable width font.
***********************

Section 1
---------

Context-Free Grammar for CSX-Lite

1)  PROGRAM --> { STMTS } EOF
2)  STMTS   --> STMT STMTS
3)           |  lambda
4)  STMT    --> ID = EXPR ;
5)           |  IF ( EXPR ) STMT
6)  EXPR    --> EXPR + ID
7)           |  EXPR - ID
8)           |  ID


Section 2
---------

State Declarations for CSX-Lite (LALR Parser)
Note:  '*' == Dot

s0  = {PROGRAM --> *{ STMTS } EOF}
s1  = {PROGRAM --> { *STMTS } EOF
       STMTS   --> *STMT STMTS
                |  lambda*
       STMT    --> *ID = EXPR ;
                |  *IF ( EXPR ) STMT}

s2  = {PROGRAM --> { STMTS* } EOF}

s3  = {STMTS   --> STMT *STMTS
       STMTS   --> *STMT STMTS
                |  lambda*
       STMT    --> *ID = EXPR ;
                |  *IF ( EXPR ) STMT}

s4  = {STMT    --> ID *= EXPR ;}

s5  = {STMT    --> IF *( EXPR ) STMT}

s6  = {PROGRAM --> { STMTS } *EOF}

s7  = {STMTS   --> STMT STMTS*}

s8  = {STMT    --> ID = *EXPR ;
       EXPR    --> *EXPR + ID
                |  *EXPR - ID
                |  *ID         }

s9  = {STMT    --> IF ( *EXPR ) STMT
       EXPR    --> *EXPR + ID
                |  *EXPR - ID
                |  *ID              }

s10 = {PROGRAM --> { STMTS } EOF*}

s11 = {STMT    --> ID = EXPR *;
       EXPR    --> EXPR *+ ID
                |  EXPR *- ID  }

s12 = {EXPR    --> ID*}

s13 = {STMT    --> IF ( EXPR *) STMT
       EXPR    --> EXPR *+ ID
                |  EXPR *- ID       }

s14 = {STMT    --> ID = EXPR ;*}

s15 = {EXPR    --> EXPR + *ID}

s16 = {EXPR    --> EXPR - *ID}

s17 = {STMT    --> IF ( EXPR ) *STMT
       STMT    --> *ID = EXPR ;
                |  *IF ( EXPR ) STMT}

s18 = {EXPR    --> EXPR + ID*}

s19 = {EXPR    --> EXPR - ID*}

s20 = {STMT    --> IF ( EXPR ) STMT*}


Section 3
---------

LALR (Shift/Reduce) Parser Uses Two Tables

Action[C][T] = Action to do in State C w/ Token T
GoTo[C][S]   = State to go to from C given S is matched

Note:  Tables have been rotated 90 degrees to aide in
       representation in these wonderful text files :)

ACTION TABLE:

   | "{" | "}" | IF | "(" | ")" | ID | = | +  | -  | ;  | EOF |
---------------------------------------------------------------
0  |  S  |     |    |     |     |    |   |    |    |    |     |
1  |     | R3  | S  |     |     | S  |   |    |    |    |     |
2  |     |  S  |    |     |     |    |   |    |    |    |     |
3  |     | R3  | S  |     |     | S  |   |    |    |    |     |
4  |     |     |    |     |     |    | S |    |    |    |     |
5  |     |     |    |  S  |     |    |   |    |    |    |     |
6  |     |     |    |     |     |    |   |    |    |    |  A  |
7  |     | R2  |    |     |     |    |   |    |    |    |     |
8  |     |     |    |     |     | S  |   |    |    |    |     |
9  |     |     |    |     |     | S  |   |    |    |    |     |
10 |     |     |    |     |     |    |   |    |    |    |     |
11 |     |     |    |     |     |    |   | S  | S  | S  |     |
12 |     |     |    |     | R8  |    |   | R8 | R8 | R8 |     |
13 |     |     |    |     |  S  |    |   | S  | S  |    |     |
14 |     | R4  | R4 |     |     | R4 |   |    |    |    |     |
15 |     |     |    |     |     | S  |   |    |    |    |     |
16 |     |     |    |     |     | S  |   |    |    |    |     |
17 |     |     | S  |     |     | S  |   |    |    |    |     |
18 |     |     |    |     | R6  |    |   | R6 | R6 | R6 |     |
19 |     |     |    |     | R7  |    |   | R7 | R7 | R7 |     |
20 |     | R5  | R5 |     |     |    |   |    |    | R5 |     |
---------------------------------------------------------------
( Key S = Shift, Ri = Reduce Production i)

GOTO TABLE:
( Sorry this one is slightly squished, needed to fit it in
 80 characters )

   | } | { | IF | ( | ) | ID | = | + | - | ; | EOF | STMTS | STMT | EXPR |
--------------------------------------------------------------------------
0  | 1 |   |    |   |   |    |   |   |   |   |     |       |      |      |
1  |   |   | 5  |   |   | 4  |   |   |   |   |     |   2   |  3   |      |
2  |   | 6 |    |   |   |    |   |   |   |   |     |       |      |      |
3  |   |   | 5  |   |   | 4  |   |   |   |   |     |   7   |  3   |      |
4  |   |   |    |   |   |    | 8 |   |   |   |     |       |      |      |
5  |   |   |    | 9 |   |    |   |   |   |   |     |       |      |      |
6  |   |   |    |   |   |    |   |   |   |   | 10  |       |      |      |
7  |   |   |    |   |   |    |   |   |   |   |     |       |      |      |
8  |   |   |    |   |   | 12 |   |   |   |   |     |       |      |  11  |
9  |   |   |    |   |   | 12 |   |   |   |   |     |       |      |  13  |
10 |   |   |    |   |   |    |   |   |   |   |     |       |      |      |
11 |   |   |    |   |   |    |   |15 |16 |14 |     |       |      |      |
12 |   |   |    |   |   |    |   |   |   |   |     |       |      |      |
13 |   |   |    |   |17 |    |   |15 |16 |   |     |       |      |      |
14 |   |   |    |   |   |    |   |   |   |   |     |       |      |      |
15 |   |   | 5  |   |   | 18 |   |   |   |   |     |       |      |      |
16 |   |   |    |   |   | 19 |   |   |   |   |     |       |      |      |
17 |   |   |    |   |   | 4  |   |   |   |   |     |       |  20  |      |
18 |   |   |    |   |   |    |   |   |   |   |     |       |      |      |
19 |   |   |    |   |   |    |   |   |   |   |     |       |      |      |
20 |   |   |    |   |   |    |   |   |   |   |     |       |      |      |
--------------------------------------------------------------------------