Description
Objectives.
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:
}
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CS451/651 Project 5 (Type Checking and Code Generation) Swami Iyer
$ $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
25
Files to Submit
1. j--.tar.gz (j-- source tree as a single gzip file)
2. report.txt (project report)
Before you submit:
• Make sure you create the gzip file j--.tar.gz such that it only includes the source files and not the binaries, which
can be done on the terminal as follows:
$ cd $j /j --
$ ant clean
$ cd ..
$ tar - czvf j - -. tar . gz j - -/*
• Make sure your report uses the given template, isn’t too verbose, doesn’t contain lines that exceed 80 characters,
and doesn’t contain spelling mistakes
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