/** Marks the code starting at the given offset. */
private void markCode(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset) {
boolean oldNext = next;
byte[] code = codeAttribute.code;
// Continue with the current instruction as long as we haven't marked it
// yet.
while (!isReachable[offset]) {
// Get the current instruction.
Instruction instruction = InstructionFactory.create(code, offset);
// Mark it as reachable.
isReachable[offset] = true;
// By default, we'll assume we can continue with the next
// instruction in a moment.
next = true;
// Mark the branch targets, if any.
instruction.accept(clazz, method, codeAttribute, offset, this);
// Can we really continue with the next instruction?
if (!next) {
break;
}
// Go to the next instruction.
offset += instruction.length(offset);
}
next = oldNext;
}
public void visitAnyInstruction(
Clazz clazz,
Method method,
CodeAttribute codeAttribute,
int offset,
Instruction instruction) {
// Append the instruction.
codeAttributeComposer.appendInstruction(offset, instruction.shrink());
}
public void visitExceptionInfo(
Clazz clazz, Method method, CodeAttribute codeAttribute, ExceptionInfo exceptionInfo) {
int startPC = Math.max(exceptionInfo.u2startPC, clipStart);
int endPC = Math.min(exceptionInfo.u2endPC, clipEnd);
int handlerPC = exceptionInfo.u2handlerPC;
int catchType = exceptionInfo.u2catchType;
// Exclude any subroutine invocations that jump out of the try block,
// by adding a try block before (and later on, after) each invocation.
for (int offset = startPC; offset < endPC; offset++) {
if (branchTargetFinder.isSubroutineInvocation(offset)) {
Instruction instruction = InstructionFactory.create(codeAttribute.code, offset);
int instructionLength = instruction.length(offset);
// Is it a subroutine invocation?
if (!exceptionInfo.isApplicable(offset + ((BranchInstruction) instruction).branchOffset)) {
if (DEBUG) {
System.out.println(
" Appending extra exception [" + startPC + " -> " + offset + "] -> " + handlerPC);
}
// Append a try block that ends before the subroutine invocation.
codeAttributeComposer.appendException(
new ExceptionInfo(startPC, offset, handlerPC, catchType));
// The next try block will start after the subroutine invocation.
startPC = offset + instructionLength;
}
}
}
if (DEBUG) {
System.out.println(
" Appending exception [" + startPC + " -> " + endPC + "] -> " + handlerPC);
}
// Append the exception. Note that exceptions with empty try blocks
// are automatically ignored.
codeAttributeComposer.appendException(new ExceptionInfo(startPC, endPC, handlerPC, catchType));
}
public void visitCodeAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute) {
// DEBUG =
// clazz.getName().equals("abc/Def") &&
// method.getName(clazz).equals("abc");
if (DEBUG) {
method.accept(clazz, new ClassPrinter());
}
branchTargetFinder.visitCodeAttribute(clazz, method, codeAttribute);
// Don't bother if there aren't any subroutines anyway.
if (!containsSubroutines(codeAttribute)) {
return;
}
if (DEBUG) {
System.out.println(
"SubroutineInliner: processing ["
+ clazz.getName()
+ "."
+ method.getName(clazz)
+ method.getDescriptor(clazz)
+ "]");
}
// Append the body of the code.
codeAttributeComposer.reset();
codeAttributeComposer.beginCodeFragment(codeAttribute.u4codeLength);
// Copy the non-subroutine instructions.
int offset = 0;
while (offset < codeAttribute.u4codeLength) {
Instruction instruction = InstructionFactory.create(codeAttribute.code, offset);
int instructionLength = instruction.length(offset);
// Is this returning subroutine?
if (branchTargetFinder.isSubroutine(offset)
&& branchTargetFinder.isSubroutineReturning(offset)) {
// Skip the subroutine.
if (DEBUG) {
System.out.println(
" Skipping original subroutine instruction " + instruction.toString(offset));
}
// Append a label at this offset instead.
codeAttributeComposer.appendLabel(offset);
} else {
// Copy the instruction, inlining any subroutine call recursively.
instruction.accept(clazz, method, codeAttribute, offset, this);
}
offset += instructionLength;
}
// Copy the exceptions. Note that exceptions with empty try blocks
// are automatically removed.
codeAttribute.exceptionsAccept(clazz, method, subroutineExceptionInliner);
if (DEBUG) {
System.out.println(" Appending label after code at [" + offset + "]");
}
// Append a label just after the code.
codeAttributeComposer.appendLabel(codeAttribute.u4codeLength);
// End and update the code attribute.
codeAttributeComposer.endCodeFragment();
codeAttributeComposer.visitCodeAttribute(clazz, method, codeAttribute);
if (DEBUG) {
method.accept(clazz, new ClassPrinter());
}
}