/**
* Performs the actual editing of a class. Does a whole mess of stuff including reading in the
* classfile, building data structures to represent the class file, converting the CFG for each
* method in the class into SSA form, perform some anlayses and optimizations on the method, and
* finally committing it back to the class file. Phew.
*/
private static void editClass(final String className) {
ClassFile classFile; // Holds info about a class (implements
// ClassInfo)
// Get information about the class className
try {
classFile = (ClassFile) Main.context.loadClass(className);
} catch (final ClassNotFoundException ex) {
System.err.println("** Couldn't find class: " + ex.getMessage());
return;
}
if (!Main.FORCE) {
// Check to see if the file is up-to-date (i.e. has been
// recompiled since it was last optimized). If so, do nothing
// because the FORCE flag is false.
final File source = classFile.file();
final File target = classFile.outputFile();
if ((source != null)
&& (target != null)
&& source.exists()
&& target.exists()
&& (source.lastModified() < target.lastModified())) {
if (Main.VERBOSE) {
System.out.println(classFile.name() + " is up to date");
}
return;
}
}
if (Main.DEBUG) {
// Print the contents of the class file to System.out
classFile.print(System.out);
}
final ClassEditor c = Main.context.editClass(classFile);
boolean skip = false;
final String name = c.type().className();
final String qual = c.type().qualifier() + "/*";
// Edit only classes explicitly mentioned.
if (Main.ONLY.size() > 0) {
skip = true;
// Only edit classes we explicitly don't name.
for (int i = 0; i < Main.ONLY.size(); i++) {
final String pkg = (String) Main.ONLY.get(i);
if (name.equals(pkg) || qual.equals(pkg)) {
skip = false;
break;
}
}
}
// Don't edit classes we explicitly skip.
if (!skip) {
for (int i = 0; i < Main.SKIP.size(); i++) {
final String pkg = (String) Main.SKIP.get(i);
if (name.equals(pkg) || qual.equals(pkg)) {
skip = true;
break;
}
}
}
if (skip) {
if (Main.VERBOSE) {
System.out.println("Skipping " + c.type().className());
}
// We're done with this class file, decrement its reference count
Main.context.release(classFile);
return;
}
// Touch the output file first. That is, create the file, but make
// it empty, just to make sure we can create it.
try {
final File f = classFile.outputFile();
if (f.exists()) {
f.delete();
}
final File dir = new File(f.getParent());
dir.mkdirs();
if (!dir.exists()) {
throw new RuntimeException("Couldn't create directory: " + dir);
}
final DataOutputStream out = new DataOutputStream(new FileOutputStream(f));
new PrintStream(out).println();
out.close();
} catch (final IOException e) {
e.printStackTrace();
System.exit(1);
}
if (Main.VERBOSE) {
System.out.println("Optimizing " + c.type().className());
}
// Finally, we can start playing with the methods...
final MethodInfo[] methods = c.methods();
final int numMethods = methods.length + 1;
;
int whichMethod = 0;
for (int j = 0; j < methods.length; j++) {
final MethodEditor m;
try {
m = Main.context.editMethod(methods[j]);
} catch (final ClassFormatException ex) {
System.err.println(ex.getMessage());
continue;
}
if (Main.TRACE) {
whichMethod++;
System.out.println(
"Optimizing "
+ name
+ "."
+ m.name()
+ " (method "
+ whichMethod
+ " of "
+ numMethods
+ ")");
}
if (Main.METHOD != null) {
// A method name has been specified on the command line using
// -only-method.
boolean pass = true;
String t = m.name() + m.type();
if (t.equals(Main.METHOD)) {
pass = false;
}
t = m.name();
if (t.equals(Main.METHOD)) {
pass = false;
}
if (pass) {
// This isn't the method we're looking for.
// Decrement its reference count.
Main.context.release(methods[j]);
continue;
}
}
if (Main.DEBUG) {
m.print(System.out);
}
if (m.isNative() || m.isAbstract()) {
// We can't edit native or abstract methods
Main.context.release(methods[j]);
continue;
}
Main.bloatMethod(m, Main.context);
}
if (Main.ANNO) {
String s = "Optimized with: EDU.purdue.cs.bloat.optimize.Main";
for (int i = 0; i < Main.ARGS.length; i++) {
if ((Main.ARGS[i].indexOf(' ') >= 0)
|| (Main.ARGS[i].indexOf('\t') >= 0)
|| (Main.ARGS[i].indexOf('\r') >= 0)
|| (Main.ARGS[i].indexOf('\n') >= 0)) {
s += " '" + Main.ARGS[i] + "'";
} else {
s += " " + Main.ARGS[i];
}
}
System.out.println(s);
// c.constants().addConstant(Constant.UTF8, s);
}
Main.context.commit(classFile);
Main.context.release(classFile);
if (Main.TRACE) {
System.out.println(Main.context.toString());
}
}
/** Runs BLOAT on a method. */
public static void bloatMethod(final MethodEditor m, final BloatContext context) {
try {
if (Main.COMPACT_ARRAY_INIT) {
// Compact the initialization of arrays of the basic types by
// putting the values of the array into a string in the constant
// pool. The initialization code is replaced with a loop that
// loads the array from the string in the constant pool.
if (Main.TRACE) {
System.out.println(" Compacting Arrays: " + Main.dateFormat.format(new Date()));
}
CompactArrayInitializer.transform(m);
if (Main.DEBUG) {
System.out.println("---------- After compaction:");
m.print(System.out);
System.out.println("---------- end print");
}
}
FlowGraph cfg; // The control flow graph for a method
if (Main.TRACE) {
System.out.println(" Constructing CFG: " + Main.dateFormat.format(new Date()));
}
try {
// Construct the control flow graph for method m
cfg = new FlowGraph(m);
} catch (final ClassFormatException ex) {
System.err.println(ex.getMessage());
context.release(m.methodInfo());
return;
}
// We separate out initialization since before this the FlowGraph
// more exactly represents the input program.
cfg.initialize();
if (Main.TRACE) {
System.out.println(" Transforming to SSA: " + Main.dateFormat.format(new Date()));
}
SSA.transform(cfg);
if (FlowGraph.DEBUG) {
System.out.println("---------- After SSA:");
cfg.print(System.out);
System.out.println("---------- end print");
}
if (Main.DEBUG) {
cfg.visit(new VerifyCFG(false));
}
if (!Tree.USE_STACK) {
// Do copy propagation and value numbering first to get rid of
// all the extra copies inserted for dups. If they're left in,
// it really slows down value numbering.
if (Main.PROP) {
if (Main.DEBUG) {
System.out.println("-----Before Copy Propagation-----");
}
if (Main.TRACE) {
System.out.println(" Copy propagation: " + Main.dateFormat.format(new Date()));
}
final ExprPropagation copy = new ExprPropagation(cfg);
copy.transform();
if (Main.DEBUG) {
cfg.visit(new VerifyCFG(false));
}
if (Main.DEBUG) {
System.out.println("------After Copy Propagation-----");
cfg.print(System.out);
}
}
}
DeadCodeElimination dce = null;
if (Main.DCE) {
if (Main.TRACE) {
System.out.println(" Dead Code Elimination: " + Main.dateFormat.format(new Date()));
}
if (Main.DEBUG) {
System.out.println("---Before Dead Code Elimination--");
}
dce = new DeadCodeElimination(cfg);
dce.transform();
if (Main.DEBUG) {
cfg.visit(new VerifyCFG(false));
}
if (Main.DEBUG) {
System.out.println("---After Dead Code Elimination---");
cfg.print(System.out);
}
}
if (Main.INFER) {
if (Main.DEBUG) {
System.out.println("---------Doing type inference--------");
}
if (Main.TRACE) {
System.out.println(" Type Inferencing: " + Main.dateFormat.format(new Date()));
}
TypeInference.transform(cfg, context.getHierarchy());
}
if (Main.NUMBER) {
if (Main.TRACE) {
System.out.println(" Value Numbering: " + Main.dateFormat.format(new Date()));
}
if (Main.DEBUG) {
System.out.println("--------Doing value numbering--------");
}
(new ValueNumbering()).transform(cfg);
}
if (Main.FOLD) {
if (Main.DEBUG) {
System.out.println("--------Before Value Folding---------");
}
if (Main.TRACE) {
System.out.println(" Value Folding: " + Main.dateFormat.format(new Date()));
}
(new ValueFolding()).transform(cfg);
if (Main.DEBUG) {
cfg.visit(new VerifyCFG());
}
if (Main.DEBUG) {
System.out.println("---------After Value Folding---------");
cfg.print(System.out);
}
}
if (Main.PRE) {
if (Main.DEBUG) {
System.out.println("-------------Before SSAPRE-----------");
}
if (Main.TRACE) {
System.out.println(" SSAPRE: " + Main.dateFormat.format(new Date()));
}
final SSAPRE pre = new SSAPRE(cfg, context);
pre.transform();
if (Main.DEBUG) {
cfg.visit(new VerifyCFG());
}
if (Main.DEBUG) {
System.out.println("-------------After SSAPRE------------");
cfg.print(System.out);
}
}
if (Main.FOLD) {
if (Main.DEBUG) {
System.out.println("--------Before Value Folding---------");
}
if (Main.TRACE) {
System.out.println(" Value Folding: " + Main.dateFormat.format(new Date()));
}
(new ValueFolding()).transform(cfg);
if (Main.DEBUG) {
cfg.visit(new VerifyCFG());
}
if (Main.DEBUG) {
System.out.println("---------After Value Folding---------");
cfg.print(System.out);
}
}
if (Main.PROP) {
if (Main.DEBUG) {
System.out.println("-------Before Copy Propagation-------");
}
if (Main.TRACE) {
System.out.println(" Copy Propagation " + Main.dateFormat.format(new Date()));
}
final ExprPropagation copy = new ExprPropagation(cfg);
copy.transform();
if (Main.DEBUG) {
cfg.visit(new VerifyCFG());
}
if (Main.DEBUG) {
System.out.println("--------After Copy Propagation-------");
cfg.print(System.out);
}
}
// make sure we've done at least one thing since the last DCE
if (Main.DCE && (Main.INFER || Main.NUMBER || Main.FOLD || Main.PRE || Main.PROP)) {
if (Main.DEBUG) {
System.out.println("-----Before Dead Code Elimination----");
}
if (Main.TRACE) {
System.out.println(" Dead Code Elimination: " + Main.dateFormat.format(new Date()));
}
dce = new DeadCodeElimination(cfg);
dce.transform();
if (Main.DEBUG) {
cfg.visit(new VerifyCFG());
}
if (Main.DEBUG) {
System.out.println("-----After Dead Code Elimination-----");
cfg.print(System.out);
}
}
if (Main.PERSIST) {
(new PersistentCheckElimination()).transform(cfg);
}
if (Main.DIVA) {
if (Main.DEBUG) {
System.out.println("-----Before DIVA------");
}
if (Main.TRACE) {
System.out.println(" DIVA: " + Main.dateFormat.format(new Date()));
}
(new InductionVarAnalyzer()).transform(cfg);
if (Main.DEBUG) {
System.out.println("-----After DIVA-----");
cfg.print(System.out);
}
}
/*
* if (STACK_ALLOC) { if (DEBUG) {
* System.out.println("------------Before StackPRE----------"); }
*
* StackPRE pre = new StackPRE(cfg); pre.transform();
*
* if (DEBUG) { cfg.visit(new VerifyCFG()); }
*
* if (DEBUG) { System.out.println("------------After
* StackPRE-----------"); cfg.print(System.out); } }
*/
// Do the new stack optimization
if (Main.OPT_STACK_2) {
if (Main.TRACE) {
System.out.println(" New stack optimization: " + Main.dateFormat.format(new Date()));
}
// generate code without doing liveness or register allocation
final CodeGenerator codegen = new CodeGenerator(m);
codegen.replacePhis(cfg);
m.clearCode2();
cfg.visit(codegen);
// do stack optimization on the bytecode
final StackOpt so = new StackOpt();
so.transform(m);
// convert it back to a cfg
cfg = new FlowGraph(m);
cfg.initialize();
// convert it back to SSA
SSA.transform(cfg);
// do more dead code elimination (eliminate stores)
dce = new DeadCodeElimination(cfg);
dce.transform();
}
if (Main.TRACE) {
System.out.println(" Register allocation: " + Main.dateFormat.format(new Date()));
}
if (Main.VERIFY) {
try {
cfg.visit(new VerifyCFG());
} catch (final IllegalArgumentException ee) {
System.out.println(
" NOTE: CFG did not verify while "
+ "bloating "
+ m.name()
+ " after all optimizations. Exception: "
+ ee);
}
}
// We're all done performing optimizations. Let's generate some code
// and go home.
// Perform liveness analysis of variables in the method.
// Assign local variables ("registers") to expression values.
final Liveness liveness = new Liveness(cfg);
final RegisterAllocator alloc = new RegisterAllocator(cfg, liveness);
// Gather information which can be used to optimize use of the stack
if (CodeGenerator.OPT_STACK) {
if (Main.TRACE) {
System.out.println(" Old stack optimization: " + Main.dateFormat.format(new Date()));
}
StackOptimizer.optimizeCFG(cfg);
}
if (Main.TRACE) {
System.out.println(" Code Generation: " + Main.dateFormat.format(new Date()));
}
// Start the code generation process.
final CodeGenerator codegen = new CodeGenerator(m);
codegen.replacePhis(cfg);
if (Main.DEBUG) {
System.out.println("After fixing Phis------------------------");
cfg.print(System.out);
System.out.println("End print--------------------------------");
}
codegen.simplifyControlFlow(cfg);
codegen.allocReturnAddresses(cfg, alloc);
if (Main.DEBUG) {
System.out.println("After removing empty blocks--------------");
cfg.print(System.out);
System.out.println("End print--------------------------------");
}
// Clear the old contents of the bytecode store and generate new
// code.
// Code is generated using a visitor pattern on the CFG.
m.clearCode();
cfg.visit(codegen);
Peephole.transform(m);
// Commit any changes that have been made to the method
context.commit(m.methodInfo());
} catch (final Exception ex99) {
final String msg =
"** Exception while optimizing "
+ m.name()
+ m.type()
+ " of class "
+ m.declaringClass().name();
System.err.println(msg);
System.err.println(ex99.getMessage());
ex99.printStackTrace(System.err);
System.exit(1);
}
}
/**
* Adds residency/update/swizzle checks to all of the methods in a given class.
*
* @param context Information about all the classes we're dealing with
* @param info Information about the class we're decorating
*/
private static void decorateClass(final EditorContext context, final ClassInfo info) {
final ClassFile classFile = (ClassFile) info;
// Check to see if the class file is up-to-date
if (!Main.FORCE) {
final File source = classFile.file();
final File target = classFile.outputFile();
if ((source != null)
&& (target != null)
&& source.exists()
&& target.exists()
&& (source.lastModified() < target.lastModified())) {
if (Main.VERBOSE > 1) {
System.out.println(classFile.name() + " is up to date");
}
return;
}
}
if (Main.VERBOSE > 2) {
classFile.print(System.out);
}
final ClassEditor c = context.editClass(info);
boolean skip = false;
final String name = c.type().className();
final String qual = c.type().qualifier() + "/*";
// Edit only classes explicitly mentioned.
if (Main.ONLY.size() > 0) {
skip = true;
// Only edit classes we explicitly don't name.
for (int i = 0; i < Main.ONLY.size(); i++) {
final String pkg = (String) Main.ONLY.get(i);
if (name.equals(pkg) || qual.equals(pkg)) {
skip = false;
break;
}
}
}
// Don't edit classes we explicitly skip.
if (!skip) {
for (int i = 0; i < Main.SKIP.size(); i++) {
final String pkg = (String) Main.SKIP.get(i);
if (name.equals(pkg) || qual.equals(pkg)) {
skip = true;
break;
}
}
}
if (skip) {
if (Main.VERBOSE > 0) {
System.out.println("Skipping " + c.type().className());
}
context.release(info);
return;
}
if (Main.VERBOSE > 0) {
System.out.println("Decorating class " + c.type().className());
}
if (Main.VERBOSE > 2) {
((ClassFile) info).print(System.out);
}
final MethodInfo[] methods = c.methods();
// Add residency checks (via transform()) to each method in the class
for (int j = 0; j < methods.length; j++) {
MethodEditor m;
try {
m = context.editMethod(methods[j]);
} catch (final ClassFormatException ex) {
System.err.println(ex.getMessage());
continue;
}
Main.transform(m);
context.commit(methods[j]);
}
context.commit(info);
}