CS451/651-Project 5 Type Checking and Code Generation Solved

1.   Implement type checking for the Java programming constructs that were introduced in j-- as part of Project 3 (Parsing).

2.   Implement JVM code generation for those Java programming constructs.

To compile the j-- compiler, run the following command:

$ ant clean compile jar

To compile a j-- program P.java, run the following command:

$ $j/j--/bin/j-- P.java

Run the following command to run the j-- program P.class:

$ java P

Problem 1. (Long and Double Basic Types) Add support for long and double basic types.

$ $j/j--/bin/j-- BasicTypes.java

$ java BasicTypes 1.0 42

3.14159

145236

Problem 2. (Operators) Add support for the following operators.

~
!=
/
/=
-=
++
--
*=
%
%=
 
=
 
=
=
<< 
<<=
< 
^
^=
|
|=
||
&
&=
$ $j/j--/bin/j-- Operators.java

$ java Operators false true 2

2 true false
Problem 3. (Conditional Expression) Add support for conditional expression (e1 ? e2 : e3).

$ $j/j--/bin/j-- ConditionalExpression.java

$ java ConditionalExpression 31 odd

$ java ConditionalExpression 42 even
Problem 4. (Switch Statement) Add support for a switch statement. Here’s some code you may want to use to decide which instruction (TABLESWITCH or LOOKUPSWITCH) to emit:

long table_space_cost = 4 + ((long) hi - lo + 1); // words

long table_time_cost = 3; // comparisons long lookup_space_cost = 3 + 2 * (long) nlabels; long lookup_time_cost = nlabels; int opcode = (nlabels 0 && table_space_cost + 3 * table_time_cost <= lookup_space_cost

+ 3 * lookup_time_cost) ? TABLESWITCH : LOOKUPSWITCH;
Where hi is the highest case label value, lo is the lowest case label value, and nlabels are the total real case labels in the switch statement. For example, in the following code, 1, 3, and 5 are the real labels, whereas 2 and 4 are the fake labels to be generated.

switch (a) { case 1: case 3:

case 5:

}


$ $j/j--/bin/j-- SwitchStatement.java

$ java SwitchStatement 4 Spring

$ java SwitchStatement 7

Summer

$ java SwitchStatement 10

Fall
Problem 5. (Do-while Statement) Add support for a do-while statement.

$ $j/j--/bin/j-- DoWhileStatement.java

$ java DoWhileStatement

55

Problem 6. (For Statement) Add support for a for statement.

$ $j/j--/bin/j-- ForStatement.java

$ java ForStatement

55

Problem 7. (Exception Handlers) Add support for exception handling, which involves supporting the try, catch, finally, throw, and throws clauses.

$ $j/j--/bin/j-- ExceptionHandlers.java

$ java ExceptionHandlers 42

42: The answer to life, the universe and everything! Done!

$ java ExceptionHandlers 43

43

Done!

Problem 8. (Interface Type Declaration) Implement support for interface declaration.

$ $j/j--/bin/j-- Interface.java

$ java Interface 5