BitMap MethodLiveness::BasicBlock::get_liveness_at(ciMethod* method, int bci) {
BitMap answer(NEW_RESOURCE_ARRAY(uintptr_t, _analyzer->bit_map_size_words()),
_analyzer->bit_map_size_bits());
#ifndef ASSERT
if (bci == start_bci()) {
answer.set_from(_entry);
return answer;
}
#endif
answer.clear();
ciByteCodeStream bytes(method);
bytes.reset_to_bci(bci);
bytes.set_max_bci(limit_bci());
compute_gen_kill_range(&bytes);
answer.set_union(_normal_exit);
answer.set_difference(_kill);
answer.set_union(_gen);
answer.set_union(_exception_exit);
#ifdef ASSERT
if (bci == start_bci()) {
assert(answer.is_same(_entry), "optimized answer must be accurate");
}
#endif
return answer;
}
// ------------------------------------------------------------------
// ciBlock::print_on
void ciBlock::print_on(outputStream* st) const {
st->print_cr("--------------------------------------------------------");
st->print ("ciBlock [%d - %d) control : ", start_bci(), limit_bci());
if (control_bci() == fall_through_bci) {
st->print_cr("%d:fall through", limit_bci());
} else {
st->print_cr("%d:%s", control_bci(),
Bytecodes::name(method()->java_code_at_bci(control_bci())));
}
if (Verbose || WizardMode) {
method()->print_codes_on(start_bci(), limit_bci(), st);
}
}
void MethodLiveness::BasicBlock::propagate(MethodLiveness *ml) {
// These set operations could be combined for efficiency if the
// performance of this analysis becomes an issue.
_entry.set_union(_normal_exit);
_entry.set_difference(_kill);
_entry.set_union(_gen);
// Note that we merge information from our exceptional successors
// just once, rather than at individual bytecodes.
_entry.set_union(_exception_exit);
if (TraceLivenessGen) {
tty->print_cr(" ** Visiting block at %d **", start_bci());
print_on(tty);
}
int i;
for (i=_normal_predecessors->length()-1; i>=0; i--) {
BasicBlock *block = _normal_predecessors->at(i);
if (block->merge_normal(_entry)) {
ml->work_list_add(block);
}
}
for (i=_exception_predecessors->length()-1; i>=0; i--) {
BasicBlock *block = _exception_predecessors->at(i);
if (block->merge_exception(_entry)) {
ml->work_list_add(block);
}
}
}
void MethodLiveness::BasicBlock::compute_gen_kill(ciMethod* method) {
ciBytecodeStream bytes(method);
bytes.reset_to_bci(start_bci());
bytes.set_max_bci(limit_bci());
compute_gen_kill_range(&bytes);
}
MethodLivenessResult MethodLiveness::BasicBlock::get_liveness_at(ciMethod* method, int bci) {
MethodLivenessResult answer(NEW_RESOURCE_ARRAY(uintptr_t, _analyzer->bit_map_size_words()),
_analyzer->bit_map_size_bits());
answer.set_is_valid();
#ifndef ASSERT
if (bci == start_bci()) {
answer.set_from(_entry);
return answer;
}
#endif
#ifdef ASSERT
ResourceMark rm;
BitMap g(_gen.size());
g.set_from(_gen);
BitMap k(_kill.size());
k.set_from(_kill);
#endif
if (_last_bci != bci || trueInDebug) {
ciBytecodeStream bytes(method);
bytes.reset_to_bci(bci);
bytes.set_max_bci(limit_bci());
compute_gen_kill_range(&bytes);
assert(_last_bci != bci ||
(g.is_same(_gen) && k.is_same(_kill)), "cached computation is incorrect");
_last_bci = bci;
}
answer.clear();
answer.set_union(_normal_exit);
answer.set_difference(_kill);
answer.set_union(_gen);
answer.set_union(_exception_exit);
#ifdef ASSERT
if (bci == start_bci()) {
assert(answer.is_same(_entry), "optimized answer must be accurate");
}
#endif
return answer;
}