* WARNING!!! For the compiler to work, the sim.dtd must be at the location * specified in the system property autohit.dtd.location. *
* The private methods translate Token() matches the textual tokens, as defined in the * dtd to numerics that are used by the rest of the compiler. Any new tokens * need to be added to that method. *
* I can think of several more elegant approaches to making this compiler, but until the * XML parsers settle a bit, I'm not going to bother... *
* IMPORTANT NOTE!!!! The XML parser WITH DTD ensure instructions are * coded in the proper order. ALL of the code below assumes this!!! * If instructions come out of order or in disallowed places * (like a seek outside of a get), I GUARANTEE you'll get a runaway * compiler... *
* Logging will be done to the autohit.creator.sim namespace. It is set for
* pretty and
*
* @author Erich P. Gatejen
* @version 1.1
* Version History
* EPG - Initial - 14Apr03
*
*/
public class SimCompiler extends XmlCompiler implements SimLanguage {
private final static String DTD_NAME = "sim.dtd";
private final static String MY_TYPE_OF_EXEC = "sim1";
// We'll do subtractive compares for IF. This might change.
// Lexical elements and attriutes
// parse tokens
/**
* The work-in-progress object code
*/
protected VMExecutableWrapper ob;
/**
* Symbol table for lookups
*/
protected HashMap symboltable;
/**
* Stack for fixups
*/
protected Stack fixupstack;
/**
* Local name - UID
*/
private String localname = "UNKNOWN";
/**
* Default Constructor. This is the only and default constructor.
*
* @throws Exception any exception invalidates the compiler.
*/
public SimCompiler() throws Exception {
super();
}
/**
* Constructor. This is the only and default constructor.
*
* @throws Exception any exception invalidates the compiler.
*/
public SimCompiler(SystemContext sc) throws Exception {
super(DTD_NAME, sc);
}
/**
* Compile the xml tree into an VMExecutable object.
*
* We will create a new log for each run, so that we can uniquely
* identify them.
*
* @param xd A parsed XML document.
* @return a reference to the target object, in this case it will be a VMExecutableWrapper, or null if it failed.
* @see autohit.vm.VMExecutableWrapper
*/
public Object build(Document xd) {
int idx;
NodeList rootChildren;
Element itemTree = null;
Element codeTree = null;
int numNodes;
Node scratchNode;
String scratchString;
// Any exception or verification check aborts the compile
try {
// Ok, build our working Sim object
ob = new VMExecutableWrapper();
ob.create();
// Create our symbol table and fixup stack
symboltable = new HashMap();
fixupstack = new Stack();
// set defaults attributes
ob.exec.major = 0;
// set any default attributes
ob.exec.type = MY_TYPE_OF_EXEC;
ob.exec.minor = 0;
ob.exec.output = null; // assume there is nothign to return
// Get the root element and normalize
Element root = (Element) xd.getDocumentElement();
root.normalize();
// Peal out the
* EPG - Update to add goto and references - 13Jul03 sub-trees
rootChildren = (NodeList) root.getChildNodes();
numNodes = rootChildren.getLength();
while (numNodes > 0) {
scratchNode = rootChildren.item(numNodes - 1);
if (scratchNode instanceof Element) {
scratchString = scratchNode.getNodeName();
if (scratchString.charAt(0) == 'i') {
itemTree = (Element) scratchNode;
} else if (scratchString.charAt(0) == 'c') {
codeTree = (Element) scratchNode;
}
}
numNodes--;
}
if (itemTree == null) {
runtimeError("Missing infomation block.");
throw new Exception();
}
// Deal with the tree
// Basicall, I'm gonna go wtih recursion. I don't think it should
// get very deep.
try {
processCode(codeTree);
// Put a NOP on the end of the executable
ob.emit(new VMINop());
ob.clean();
// fixup goto symbols
ListIterator li = fixupstack.listIterator();
VMIGoto jcandidate;
NOPair nocandidate;
Integer currentgoto;
while (li.hasNext()) {
nocandidate = (NOPair) li.next();
if (symboltable.containsKey(nocandidate.n)) {
jcandidate = (VMIGoto) nocandidate.o;
currentgoto = (Integer) symboltable.get(nocandidate.n);
jcandidate.t = currentgoto.intValue();
runtimeDebug(
"Fixup GOTO for label="
+ nocandidate.n
+ " target="
+ jcandidate.t);
} else {
runtimeError(
"Broken GOTO. No label for "
+ nocandidate.n
+ ".");
}
}
} catch (Exception e) {
// an otherwise uncaught exception. A runaway compiler...
runtimeError("FATAL ERROR. Runaway compilation errors. Stopping compile.");
ob = null;
}
} catch (Exception e) {
myLog.error(
"CRITICAL ERROR encountered. Stopping compile of " + localname + ". "
+ e.toString(),
AutohitErrorCodes.CODE_COMPILE_ERROR);
myLog.error(e.toString());
ob = null; // leave the objectCode as null;
}
// ditch data as it falls out of scope
symboltable = null;
fixupstack = null;
// clean up logs
int err = numberErrors();
runtimeLog.error("Total errors for " + localname + " : " + err);
runtimeLog.warning("Total errors for " + localname + " : " + numberWarnings());
if (err > 0) {
runtimeLog.info("COMPILE FAILED " + localname + " DUE TO ERRORS.");
ob = null;
}
return ob;
}
/**
* Processes info section tags.
*/
private void processItem(Element en) throws Exception {
String tempText;
String name;
//runtimeDebug("ENTER --- " + en.getTagName());
name = en.getTagName().toLowerCase();
NodeList itemTreeChildren;
int idx;
Node sNode;
// Parse the token and call a handler
if (name.charAt(0) == 'n') {
if (name.charAt(1) == 'a') {
//NAME
tempText = getText(en.getFirstChild());
if (tempText == null) {
runtimeError("Empty MICROCODE
* 1- if (oper exists) OP = oper
* 2- else OP = '=' (default)
* 3- if (eval exists) i.eval(eval)
* 4- else if (value exists) i.load(value)
* 5- else !!ERROR
* 6- i.right
* 7- i.fetch(item)
* 8- i.math(operation)
* 9- i.if(OUTER,OP)
* 10- INNER: i.scope
* 11- (ANY)*
* 12- i.rscope
* 13- OUTER: i.nop
*/
private void handleIf(Element en) {
VMIIf myif;
int opthang = EQ; // default is =
//runtimeDebug("handleIf");
// 1- if (oper exists) OP = oper
if (en.hasAttribute(ATTR_OPERATOR)) {
String ops = en.getAttribute(ATTR_OPERATOR);
if (ops.equals(EQ_STRING)) {
opthang = EQ;
} else if (ops.equals(LT_STRING)) {
opthang = LT;
} else if (ops.equals(GT_STRING)) {
opthang = GT;
} else if (ops.equals(NOT_STRING)) {
opthang = NOT;
} else {
runtimeWarning("WARNING If has unrecognized operation. Using default \"eq\"");
opthang = EQ;
}
}
// 2- else OP = '=' (default)
// Implied since it is the default.
// 3- if (eval exists) i.eval(eval)
if (en.hasAttribute(ATTR_EVALUATOR)) {
this.emitEval(en.getAttribute(ATTR_EVALUATOR));
// 4- else if (value exists) i.load(value)
} else if (en.hasAttribute(ATTR_VALUE)) {
this.emitLoad(en.getAttribute(ATTR_VALUE));
// 5- else !!ERROR
} else {
runtimeError("ERROR Broken IF. No right value defined defined.");
this.emitLoad(en.getAttribute(LITERAL_ZERO));
// use 0 so we can finish compile
}
// 6- i.right
this.emitRight();
// 7- i.fetch(item)
this.emitFetch(en.getAttribute(ATTR_ITEM));
// 8- i.math(operation)
this.emitMath(IF_OPERATION);
// 9- i.if(OUTER, OP)
myif = new VMIIf();
myif.operFlag = opthang;
ob.emit(myif);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.if target= FIXUP LATER");
// 10- INNER: i.scope
this.emitScope();
// 11- (ANY)*
try {
processCode(en);
} catch (Exception e) {
// Stop an error unravelling here. Close the scope and move on
runtimeError("ERROR Broken IF inner.");
runtimeError(e.toString());
}
// 12- i.rscope
this.emitRScope();
// 13- OUTER: i.nop
// First fixup the if. Put a NOP for safety, so there will always be a target
myif.t = ob.nextIP();
runtimeDebug("FIXUP if target=" + myif.t);
this.emitNOP();
}
/**
* handle a ASSERT
* MICROCODE
*
* 1- if (oper NOT exists) OP = NOT
* 2- else OP = EQ
* 3- i.fetch(item)
* 4- i.assert(OUTER,OP)
* 5- INNER: i.scope
* 6- (ANY)*
* 7- i.rscope
* 8- OUTER: i.nop
*
*/
private void handleAssert(Element en) {
VMIAssert myassert;
int opthang = EQ; // default is =
//runtimeDebug("handleAssert");
// 1- if (oper exists) OP = oper
if (en.hasAttribute(ATTR_OPERATOR)) {
String ops = en.getAttribute(ATTR_OPERATOR);
if (ops.equals(EQ_STRING)) {
opthang = EQ;
} else if (ops.equals(NOT_STRING)) {
opthang = NOT;
} else {
runtimeWarning("WARNING If has unrecognized operation. Using default \"eq\"");
opthang = EQ;
}
}
// 2- else OP = '=' (default)
// Implied since it is the default.
// 3- i.fetch(item)
this.emitFetch(en.getAttribute(ATTR_ITEM));
// 4- i.assert(OUTER,OP)
myassert = new VMIAssert();
myassert.operFlag = opthang;
ob.emit(myassert);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.assert target= FIXUP LATER");
// 5- INNER: i.scope
this.emitScope();
// 6- (ANY)*
try {
processCode(en);
} catch (Exception e) {
// Stop an error unravelling here. Close the scope and move on
runtimeError("ERROR Broken ASSERT inner.");
runtimeError(e.toString());
}
// 7- i.rscope
this.emitRScope();
// 8- OUTER: i.nop
// First fixup the assert. Put a NOP for safety, so there will always be a target
myassert.t = ob.nextIP();
runtimeDebug("FIXUP assert target=" + myassert.t);
this.emitNOP();
}
/**
* handle subroutine.
* MICROCODE
* 1- i.scope
* 2- (SET)*
* 3- i.subr(name)
* 4- i.rscope
* 5- if (result exist) i.store(result)
*/
private void handleSubroutine(Element en) {
String name = en.getAttribute(ATTR_NAME);
runtimeDebug("handleSubroutine. name=" + name);
// 1- i.scope
this.emitScope();
// 2- (SET)*
try {
// recurse into the children
processCode(en);
// 3- i.call(name)
this.emitSubr(name);
} catch (Exception e) {
// Stop an error unravelling here. Close the scope and move on
runtimeError("ERROR handleCall. Broken call." + name);
runtimeError(e.toString());
ob.emit(new VMIRScope());
return;
}
// 4- i.rscope
this.emitRScope();
// 5- if (result exist) i.store(result)
if (en.hasAttribute(ATTR_RESULT)) {
this.emitStore(en.getAttribute(ATTR_RESULT));
}
}
/**
* handle a label
* MICROCODE
* 1- {mark label}
*/
private void handleLabel(Element en) {
String name = en.getAttribute(ATTR_NAME);
//runtimeDebug("handleLabel. name=" + name);
// 1- {mark label}. Put it in the symboltable with current IP
// See if there is a duplicate.
if (symboltable.containsKey(name)) {
runtimeError("Duplicate label declared. label=" + name);
} else {
symboltable.put(name, new Integer(ob.nextIP()));
}
}
/**
* handle a WHILE
* MICROCODE
* 1- i.scope
* 2- DO: i.load(value)
* 3- i.right
* 4- i.fetch(name)
* 5- i.math("=")
* 6- i.if(DONE)
* 7- (ANY)*
* 8- i.jump(DO)
* 9- DONE: i.rscope
*/
private void handleWhile(Element en) {
int loopdo;
VMIIf myif;
VMIJump myjump;
//runtimeDebug("handleWhile");
// 1- i.scope
this.emitScope();
// 2- DO: i.load(value)
loopdo = ob.nextIP(); // DO points at #2
this.emitLoad(en.getAttribute(ATTR_VALUE));
// 3- i.right
this.emitRight();
// 4- i.fetch(name)
this.emitFetch(en.getAttribute(ATTR_NAME));
// 5- i.math("=")
this.emitMath(EQ_OPERATION);
// 6- i.if(DONE)
myif = new VMIIf();
ob.emit(myif);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.if target= FIXUP LATER");
// 7- (ANY)*
try {
processCode(en);
} catch (Exception e) {
// Stop an error unravelling here. Close the scope and move on
runtimeError("ERROR Broken FOR inner.");
runtimeError(e.toString());
}
// 8- i.jump(DO)
myjump = new VMIJump();
myjump.t = loopdo;
ob.emit(myjump);
runtimeDebug("EMIT(" + (ob.nextIP() - 1) + ") i.jump target=" + loopdo);
// 9- DONE: i.rscope
// First fixup the if
myif.t = ob.nextIP();
this.emitRScope();
}
/**
* handle a MATH
* MICROCODE
* 1- if (eval exists) i.eval(eval)
* 2- else if (value exists) i.load(value)
* 3- else !!ERROR
* 4- i.right()
* 5- i.fetch(left)
* 6- i.math(oper)
* 7- if (output exists) i.store(output)
* 8- else i.store(left)
*/
private void handleMath(Element en) {
//runtimeDebug("handleMath");
// 1- if (eval exists) i.eval(eval)
if (en.hasAttribute(ATTR_EVALUATOR)) {
this.emitEval(en.getAttribute(ATTR_EVALUATOR));
// 2- else if (value exists) i.load(value)
} else if (en.hasAttribute(ATTR_VALUE)) {
this.emitLoad(en.getAttribute(ATTR_VALUE));
// 3- else !!ERROR
} else {
runtimeError("ERROR Broken Math. No right value defined.");
this.emitLoad(LITERAL_ZERO);
// use 0 so we can finish compile
}
// 4- i.right
this.emitRight();
// 5- i.fetch(item)
this.emitFetch(en.getAttribute(ATTR_LEFT));
// 6- i.math(operation)
this.emitMath(en.getAttribute(ATTR_OPERATOR));
// 7- if (output exists) i.store(output)
if (en.hasAttribute(ATTR_OUTPUT)) {
this.emitStore(en.getAttribute(ATTR_OUTPUT));
// else i.store(left)
} else {
this.emitStore(en.getAttribute(ATTR_LEFT));
}
}
/**
* handle a return. It just emits a fault
* MICROCODE
* 1- i.fault
*/
private void handleReturn(Element en) {
//runtimeDebug("handleReturn");
// 1- i.fault
this.emitFault();
}
// == ===============================================================================
// == = HELPERS =
// == ===============================================================================
/**
* Valid string.
*
* Checks if the reference is not null and the string contains characters.
*
* @param s the string to check.
* @return true if valid, otherwise false
*/
private boolean isValid(String s) {
if ((s == null) || (s.length() < 1))
return false;
else
return true;
}
/**
* Get the text out of an XML node.
*
* @param cdn XML node.
* @return the text.
*/
private String getText(Node cdn) {
try {
if ((cdn.getNodeType() == Node.TEXT_NODE)
|| (cdn.getNodeType() != Node.CDATA_SECTION_NODE)) {
CharacterData cdnc = (CharacterData) cdn;
return cdnc.getData();
}
} catch (Exception e) {
} // ignore. re are returning empty anyway
return null;
}
/**
* Get the text out of an XML node.
*
* @param where where it was bad.
* @param which which attribute was bad.
* @param tag which tag.
* @return the text.
*/
private void errBadAttribute(String where, String which, String tag) {
runtimeError(
"ERROR: Invalid '"
+ which
+ "' attribute for <"
+ tag
+ ">. @"
+ where);
}
/**
* emitClear
*/
private void emitClear(String name) {
VMIClear ic;
ic = new VMIClear();
ic.t = name;
ob.emit(ic);
//runtimeDebug("EMIT(" + (ob.nextIP() - 1) + ") i.clear name= " + name);
}
/**
* emitEval
*/
private void emitEval(String eval) {
VMIEval ic;
ic = new VMIEval();
ic.e = eval;
ob.emit(ic);
//runtimeDebug("EMIT(" + (ob.nextIP() - 1) + ") i.eval eval= " + eval);
}
/**
* emitReduce
*/
private void emitReduce(String buffer) {
VMIReduce ic;
ic = new VMIReduce();
ic.b = buffer;
ob.emit(ic);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.reduce name= " + buffer);
}
/**
* emitReduce
*/
private void emitLoad(String value) {
VMILoad ic;
ic = new VMILoad();
ic.l = value;
ob.emit(ic);
//runtimeDebug("EMIT(" + (ob.nextIP() - 1) + ") i.load value= " + value);
}
/**
* emitMerge
*/
private void emitMerge(String buffer) {
VMIMerge ic;
ic = new VMIMerge();
ic.b = buffer;
ob.emit(ic);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.merge buffer= " + buffer);
}
/**
* emitCall
*/
private void emitCall(String target) {
VMICall ic;
ic = new VMICall();
ic.t = target;
ob.emit(ic);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.call target= " + target);
}
/**
* emitMethod
*/
private void emitMethod(String m) {
VMIMethod ic;
ic = new VMIMethod();
ic.m = m;
ob.emit(ic);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.method method=" + m);
}
/**
* emitSubr
*/
private void emitSubr(String target) {
VMISubr ic;
ic = new VMISubr();
ic.t = target;
ob.emit(ic);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.subr target= " + target);
}
/**
* emitExec
*/
private void emitExec(String target) {
VMIExec ic;
ic = new VMIExec();
ic.c = target;
ob.emit(ic);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.exec target= " + target);
}
/**
* emitNew
*/
private void emitNew(String var) {
VMINew ic;
ic = new VMINew();
ic.v = var;
ob.emit(ic);
//runtimeDebug("EMIT(" + (ob.nextIP() - 1) + ") i.new variable= " + var);
}
/**
* emitRight
*/
private void emitRight() {
ob.emit(new VMIRight());
//runtimeDebug("EMIT(" + (ob.nextIP() - 1) + ") i.right");
}
/**
* emitFetch
*/
private void emitFetch(String var) {
VMIFetch ic;
ic = new VMIFetch();
ic.v = var;
ob.emit(ic);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.fetch variable= " + var);
}
/**
* emitMath
*/
private void emitMath(String oper) {
VMIMath ic;
ic = new VMIMath();
ic.o = oper;
ob.emit(ic);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.math operation= " + oper);
}
/**
* emitStore
*/
private void emitStore(String var) {
VMIStore ic;
ic = new VMIStore();
ic.v = var;
ob.emit(ic);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.store variable= " + var);
}
/**
* emitJump
*/
private VMIJump emitJump(int target) {
VMIJump ic;
ic = new VMIJump();
ic.t = target;
ob.emit(ic);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.Jump target= " + target);
return ic;
}
/**
* emitGoto
*/
private VMIGoto emitGoto(int target) {
VMIGoto ic;
ic = new VMIGoto();
ic.t = target;
ob.emit(ic);
//runtimeDebug(
// "EMIT(" + (ob.nextIP() - 1) + ") i.goto target= " + target);
return ic;
}
/**
* emitScope
*/
private void emitScope() {
ob.emit(new VMIScope());
//runtimeDebug("EMIT(" + (ob.nextIP() - 1) + ") i.scope");
}
/**
* emitRScope
*/
private void emitRScope() {
ob.emit(new VMIRScope());
//runtimeDebug("EMIT(" + (ob.nextIP() - 1) + ") i.rscope");
}
/**
* emitNOP
*/
private void emitNOP() {
ob.emit(new VMINop());
//runtimeDebug("EMIT(" + (ob.nextIP() - 1) + ") i.nop");
}
/**
* emitNOP
*/
private void emitFault() {
ob.emit(new VMIFault());
//runtimeDebug("EMIT(" + (ob.nextIP() - 1) + ") i.fault");
}
}