#CS536 classnote for Wednesday, April 23
#Dongqiao Li

1. About Jasmin

Jasmin translates a JVM assembly file (*.j) into a JVM bytecode file (*.class).
Each *.j file has three kinds of components:

	Directives:	starting with '.';
	Instructions: one per line, inludes both opcode and oprands;
	Labels: of the form 'id: ', on a seperate line.	

Example:

	.class public classname
	.super classname Java/Lang/Object
	.method public static F(II)V

	ldc 0
	istore 1

	;stack is allocated per method basis
	.limit stack 25	;be careful not to run out of stack limit
	.limit locals 1	;only one local  var used

	.end method

Types used:

	B = Byte	
	C = Char
	I = Int
	Z = Boolean
	V = Void
	[ = array of
	Lclasspath = as userdefined in calsspath


Example:

1) void m(int,int)		
	->	m(II)V

2) int f(String)
	->	f(Ljava/lang/String;)I

3) void m(int, int[])
	->	m(I[I)V

Hint: Can use unassebler Javap -c CLASS to search for desired JVM assembly code.


2. Code Generation

1) Write a cg() method for each AST node(some may be empty);
2) At the root of AST (classNode), create 
	boolean codeGen(PrintStream asmFile).

Utility routines are static members of ASTNode.

Add a field to exprNode and SymbolInfo:

	int adr;

One of: 
	global
	local
	stack
	literal
	none

Beginning from next class, we'll talk about the utility routines as well as the specific cg() 
methods for different classes.