constanttable.java

用Java实现的编译器。把源代码编译成SPARC汇编程序

package CatDecaf.Optimizer;
import CatDecaf.IR.*;
import CatDecaf.Utilities.*;
import java6035.tools.ASM.*;
import java.io.*;
import java.util.*;
import CatDecaf.SymTable.*;
import parser.*;
public class ConstantTable{
	public LinkedHashMap table;
	public ConstantTable parent;
	public ConstantTable child1;
	public ConstantTable child2;
	public HashSet loopKillSet;
	public boolean optFlag;
	public HashSet killSet;		//an IDDescriptor in this killSet means it cannot be looked up from the parent table
	public ConstantTable(){
		table = new LinkedHashMap();
		killSet = new HashSet();
		//parent = p;
		//optFlag = true;

	}
	public Object lookupValue(IDDescriptor idd){
		if(table.containsKey(idd)) return table.get(idd);
		if(parent != null && !killSet.contains(idd)) return  parent.lookupValue(idd);;
		return null;
	}
	public boolean checkIDDInParents(IDDescriptor idd){ //true if idd exists in ancestors
		if(parent == null) return false;
		if(parent.table.containsKey(idd)) return true;
		else return parent.checkIDDInParents(idd);
	}
	public boolean checkIDDInParents(IDDescriptor idd, Object o){ //true if idd exists with same value in ancestors
		
		if(parent == null) return false;
		if(parent.table.containsKey(idd)){
			Object o2 = parent.table.get(idd);
			if(o instanceof LtrInt)	return ( ((LtrInt)o).ltrInt_ == ((LtrInt)o2).ltrInt_ ) ;							
			else if(o instanceof LtrBoolFalse) return (o2 instanceof LtrBoolFalse);
			else if(o instanceof LtrBoolTrue) return (o2 instanceof LtrBoolTrue);
				
			return false;
		}
		else return parent.checkIDDInParents(idd, o);
	}
	public LinkedHashMap checkIDDInParentsAndGetTable(IDDescriptor idd, Object o){ //true if idd exists with same value in ancestors
		
		if(parent == null) return null;
		if(parent.table.containsKey(idd)){
			Object o2 = parent.table.get(idd);
			boolean equal = false;
			if(o instanceof LtrInt)	equal = ( ((LtrInt)o).ltrInt_ == ((LtrInt)o2).ltrInt_ ) ;							
			else if(o instanceof LtrBoolFalse) equal = (o2 instanceof LtrBoolFalse);
			else if(o instanceof LtrBoolTrue) equal = (o2 instanceof LtrBoolTrue);
			
			if(equal) return parent.table;
			return null;
		}
		else return parent.checkIDDInParentsAndGetTable(idd, o);
	}
	private void kill(IDDescriptor idd){
		if(table.containsKey(idd)) table.remove(idd);
		if(parent != null) parent.kill(idd);		
	}
	public void kill(HashSet ks){
		for(Iterator i = ks.iterator(); i.hasNext(); )
			kill((IDDescriptor)i.next());
	}
}