+++ /dev/null
-package IR;
-import java.util.*;
-
-public class TypeUtil {
- public static final String StringClass="String";
- public static final String ObjectClass="Object";
- public static final String StartupClass="StartupObject";
- public static final String TagClass="TagDescriptor";
- public static final String ThreadClass="Thread";
- State state;
- Hashtable supertable;
- Hashtable subclasstable;
-
- public TypeUtil(State state) {
- this.state=state;
- createTables();
- }
-
- public ClassDescriptor getClass(String classname) {
- ClassDescriptor cd=(ClassDescriptor)state.getClassSymbolTable().get(classname);
- return cd;
- }
-
- private void createTables() {
- supertable=new Hashtable();
-
- Iterator classit=state.getClassSymbolTable().getDescriptorsIterator();
- while(classit.hasNext()) {
- ClassDescriptor cd=(ClassDescriptor)classit.next();
- String superc=cd.getSuper();
- if (superc!=null) {
- ClassDescriptor cd_super=getClass(superc);
- if (cd_super==null) {
- throw new Error("Couldn't find class:"+superc);
- }
- supertable.put(cd,cd_super);
- }
- }
- }
-
- public ClassDescriptor getMainClass() {
- return getClass(state.main);
- }
-
- public MethodDescriptor getRun() {
- ClassDescriptor cd=getClass(TypeUtil.ThreadClass);
- for(Iterator methodit=cd.getMethodTable().getSet("run").iterator();methodit.hasNext();) {
- MethodDescriptor md=(MethodDescriptor) methodit.next();
- if (md.numParameters()!=0||md.getModifiers().isStatic())
- continue;
- return md;
- }
- throw new Error("Can't find Thread.run");
- }
-
- public MethodDescriptor getMain() {
- ClassDescriptor cd=getMainClass();
- Set mainset=cd.getMethodTable().getSet("main");
- for(Iterator mainit=mainset.iterator();mainit.hasNext();) {
- MethodDescriptor md=(MethodDescriptor)mainit.next();
- if (md.numParameters()!=1)
- continue;
- Descriptor pd=md.getParameter(0);
- TypeDescriptor tpd=(pd instanceof TagVarDescriptor)?((TagVarDescriptor)pd).getType():((VarDescriptor)pd)
- .getType();
- if (tpd.getArrayCount()!=1)
- continue;
- if (!tpd.getSymbol().equals("String"))
- continue;
-
- if (!md.getModifiers().isStatic())
- throw new Error("Error: Non static main");
- return md;
- }
- throw new Error(cd+" has no main");
- }
-
- /** Check to see if md1 is more specific than md2... Informally
- if md2 could always be called given the arguments passed into
- md1 */
-
- public boolean isMoreSpecific(MethodDescriptor md1, MethodDescriptor md2) {
- /* Checks if md1 is more specific than md2 */
- if (md1.numParameters()!=md2.numParameters())
- throw new Error();
- for(int i=0;i<md1.numParameters();i++) {
- if (!this.isSuperorType(md2.getParamType(i), md1.getParamType(i)))
- return false;
- }
- if (!this.isSuperorType(md2.getReturnType(), md1.getReturnType()))
- return false;
-
- if (!this.isSuperorType(md2.getClassDesc(), md1.getClassDesc()))
- return false;
-
- return true;
- }
-
- public MethodDescriptor getMethod(ClassDescriptor cd, String name, TypeDescriptor[] types) {
- Set methoddescriptorset=cd.getMethodTable().getSet(name);
- MethodDescriptor bestmd=null;
- NextMethod:
- for(Iterator methodit=methoddescriptorset.iterator();methodit.hasNext();) {
- MethodDescriptor currmd=(MethodDescriptor)methodit.next();
- /* Need correct number of parameters */
- if (types.length!=currmd.numParameters())
- continue;
- for(int i=0;i<types.length;i++) {
- if (!this.isSuperorType(currmd.getParamType(i),types[i]))
- continue NextMethod;
- }
- /* Method okay so far */
- if (bestmd==null)
- bestmd=currmd;
- else {
- if (isMoreSpecific(currmd,bestmd)) {
- bestmd=currmd;
- } else if (!isMoreSpecific(bestmd, currmd))
- throw new Error("No method is most specific");
-
- /* Is this more specific than bestmd */
- }
- }
- if (bestmd==null)
- throw new Error("Could find: "+name + " in "+cd);
-
- return bestmd;
- }
-
- public void createFullTable() {
- subclasstable=new Hashtable();
-
- Iterator classit=state.getClassSymbolTable().getDescriptorsIterator();
- while(classit.hasNext()) {
- ClassDescriptor cd=(ClassDescriptor)classit.next();
- ClassDescriptor tmp=cd.getSuperDesc();
-
- while(tmp!=null) {
- if (!subclasstable.containsKey(tmp))
- subclasstable.put(tmp,new HashSet());
- HashSet hs=(HashSet)subclasstable.get(tmp);
- hs.add(cd);
- tmp=tmp.getSuperDesc();
- }
- }
- }
-
- public Set getSubClasses(ClassDescriptor cd) {
- return (Set)subclasstable.get(cd);
- }
-
- public ClassDescriptor getSuper(ClassDescriptor cd) {
- return (ClassDescriptor)supertable.get(cd);
- }
-
- public boolean isCastable(TypeDescriptor original, TypeDescriptor casttype) {
- if (original.isChar()&&
- (casttype.isByte()||
- casttype.isShort()))
- return true;
-
- if (casttype.isChar()&&
- (original.isByte()||
- original.isShort()||
- original.isInt()||
- original.isLong()||
- original.isFloat()||
- original.isDouble()))
- return true;
-
- return false;
- }
-
- public boolean isSuperorType(TypeDescriptor possiblesuper, TypeDescriptor cd2) {
- //Matching type are always okay
- if (possiblesuper.equals(cd2))
- return true;
-
- if ((possiblesuper.isTag() && !cd2.isTag())||
- (!possiblesuper.isTag() && cd2.isTag()))
- return false;
-
- //Handle arrays
- if (cd2.isArray()||possiblesuper.isArray()) {
- // Object is super class of all arrays
- if (possiblesuper.getSymbol().equals(ObjectClass)&&!possiblesuper.isArray())
- return true;
-
- // If we have the same dimensionality of arrays & both are classes, we can default to the normal test
- if (cd2.isClass()&&possiblesuper.isClass()
- &&(possiblesuper.getArrayCount()==cd2.getArrayCount())&&
- isSuperorType(possiblesuper.getClassDesc(), cd2.getClassDesc()))
- return true;
-
- // Object is superclass of all array classes
- if (possiblesuper.getSymbol().equals(ObjectClass)&&cd2.isClass()
- &&(possiblesuper.getArrayCount()<cd2.getArrayCount()))
- return true;
-
- return false;
- }
-
- if (possiblesuper.isClass()&&
- cd2.isClass())
- return isSuperorType(possiblesuper.getClassDesc(), cd2.getClassDesc());
- else if (possiblesuper.isClass()&&
- cd2.isNull())
- return true;
- else if (possiblesuper.isNull())
- throw new Error(); //not sure when this case would occur
- else if (possiblesuper.isPrimitive()&&
- cd2.isPrimitive()) {
- ///Primitive widenings from 5.1.2
- if (cd2.isByte()&&(possiblesuper.isByte()||possiblesuper.isShort()||
- possiblesuper.isInt()||possiblesuper.isLong()||
- possiblesuper.isFloat()||possiblesuper.isDouble()))
- return true;
- if (cd2.isShort()&&(possiblesuper.isShort()||
- possiblesuper.isInt()||possiblesuper.isLong()||
- possiblesuper.isFloat()||possiblesuper.isDouble()))
- return true;
- if (cd2.isChar()&&(possiblesuper.isChar()||
- possiblesuper.isInt()||possiblesuper.isLong()||
- possiblesuper.isFloat()||possiblesuper.isDouble()))
- return true;
- if (cd2.isInt()&&(possiblesuper.isInt()||possiblesuper.isLong()||
- possiblesuper.isFloat()||possiblesuper.isDouble()))
- return true;
- if (cd2.isLong()&&(possiblesuper.isLong()||
- possiblesuper.isFloat()||possiblesuper.isDouble()))
- return true;
- if (cd2.isFloat()&&(possiblesuper.isFloat()||possiblesuper.isDouble()))
- return true;
- if (cd2.isDouble()&&possiblesuper.isDouble())
-
- return true;
- if (cd2.isBoolean()&&possiblesuper.isBoolean())
- return true;
-
- return false;
- } else if (possiblesuper.isPrimitive()&&(!possiblesuper.isArray())&&
- cd2.isPtr())
- return false;
- else if (cd2.isPrimitive()&&(!cd2.isArray())&&
- possiblesuper.isPtr())
- return false;
- else
- throw new Error("Case not handled:"+possiblesuper+" "+cd2);
- }
-
-
- public boolean isSuperorType(ClassDescriptor possiblesuper, ClassDescriptor cd2) {
- if (possiblesuper==cd2)
- return true;
- else
- return isSuper(possiblesuper, cd2);
- }
-
- private boolean isSuper(ClassDescriptor possiblesuper, ClassDescriptor cd2) {
- while(cd2!=null) {
- cd2=getSuper(cd2);
- if (cd2==possiblesuper)
- return true;
- }
- return false;
- }
-}
projects / IRC.git / blobdiff