/** Performs peephole optimizations on a program's live methods. */
private static void peephole(final BloatContext context) {
final Set liveMethods = new TreeSet(new MemberRefComparator());
final CallGraph cg = context.getCallGraph();
liveMethods.addAll(cg.liveMethods());
// Perform peephole optimizations. We do this separately because
// some peephole optimizations do things to the stack that
// inlining doesn't like. For instance, a peephole optimizations
// might make it so that a method has a non-empty stack upon
// return. Inlining will barf at the sight of this.
BloatBenchmark.tr("Performing peephole optimizations");
final Iterator iter = liveMethods.iterator();
while (BloatBenchmark.PEEPHOLE && iter.hasNext()) {
try {
final MethodEditor live = context.editMethod((MemberRef) iter.next());
Peephole.transform(live);
context.commit(live.methodInfo());
context.release(live.methodInfo());
} catch (final NoSuchMethodException ex314) {
BloatBenchmark.err.println("** Could not find method " + ex314.getMessage());
ex314.printStackTrace(System.err);
System.exit(1);
}
}
}
/** 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);
}
}
