rscope.cpp

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/* Copyright 1994 - 1996, LongView Technologies L.L.C. $Revision: 1.57 $ */
/* Copyright (c) 2006, Sun Microsystems, Inc.
All rights reserved.

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# include "incls/_precompiled.incl"

# ifdef DELTA_COMPILER

# include "incls/_rscope.cpp.incl"

RScope::RScope(RNonDummyScope* s, int bci) : _senderBCI(bci) {
  _sender = s; 
  if (s) {
    s->addScope(bci, this);
    nsends = s->nsends;
  } else {
    nsends = -1;
  }
}

GrowableArray<RScope*>* RNullScope::subScopes(int bci) const {
  return new GrowableArray<RScope*>(1);
}

static int compare_pcDescs(PcDesc** a, PcDesc** b) {
  // to sort by descending scope and ascending bci
  int diff = (*b)->scope - (*a)->scope;
  return diff ? diff : (*a)->byteCode - (*b)->byteCode;
}
  
int RNonDummyScope::compare(RNonDummyScope** a,  RNonDummyScope** b) {
  return (*b)->scopeID() - (*a)->scopeID();
}
  
RNonDummyScope::RNonDummyScope(RNonDummyScope* s, int bci, methodOop m, int level)
: RScope(s, bci),  
  _level(level), 
  uncommon(1),
  ncodes(m == NULL ? 1 : m->size_of_codes() * oopSize) {
  _subScopes = NEW_RESOURCE_ARRAY(GrowableArray<RScope*>*, ncodes + 1);
  for (int i = 0; i <= ncodes; i++) _subScopes[i] = NULL;
}

RInlinedScope::RInlinedScope(RNonDummyScope* s, int bci, const nmethod* n, ScopeDesc* d, int level)
: RNonDummyScope(s, bci, d->method(), level), desc(d), nm(n) {}


RPICScope::RPICScope(const nmethod* c, PcDesc* pc, CompiledIC* s, klassOop k,
                     ScopeDesc* dsc, nmethod* n, methodOop m, int ns, int lev, bool tr)
  : RNonDummyScope(NULL, pc->byteCode, m, lev), 
    caller(c), _sd(s), pcDesc(pc), klass(k), nm(n), _method(m), trusted(tr), desc(dsc) {
  nsends = ns; 
  extended = false;
}

RDatabaseScope::RDatabaseScope(RNonDummyScope* sender, int bci, klassOop receiver_klass, methodOop method, int level)
: RNonDummyScope(sender, bci, method, level) {
  _receiver_klass = receiver_klass;
  _method         = method;
  _key            = LookupKey::allocate(receiver_klass, method->is_blockMethod() ? oop(method) : oop(_method->selector()));
  _uncommon       = new GrowableArray<bool>(ncodes);
  for (int i = 0; i <= ncodes; i++) _uncommon->append(false);
}

RUntakenScope::RUntakenScope(RNonDummyScope* sender, PcDesc* p, bool u)
  : RNonDummyScope(sender, p->byteCode, NULL, 0), isUncommon(u), pc(p) { 
  int i = 0;    // to allow setting breakpoints
}

RUninlinableScope::RUninlinableScope(RNonDummyScope* sender, int bci) : RNullScope(sender, bci) { 
  int i = 0;    // to allow setting breakpoints
}

RInterpretedScope::RInterpretedScope(RNonDummyScope* sender, int bci, LookupKey* key, 
                                     methodOop m, int level, bool trusted) 
  : RNonDummyScope(sender, bci, m, level) {
  _key = key; _method = m; this->nsends = m->invocation_count(); this->trusted = trusted;
  extended = false;
}

LookupKey* RInlinedScope::key() const {
  return desc->key();
}

LookupKey* RPICScope::key() const {
  // If we have a nmethod, return the key of the nmethod
  if (nm)
    return (LookupKey*) &nm->key;

  // If we have a scope desc, return the key of the scope desc
  if (desc)
    return desc->key();

  // If we have a send desc, return an allocated lookup key
  if (sd()) {
    return sd()->isSuperSend()
         ? LookupKey::allocate(klass, _method)
         : LookupKey::allocate(klass, _method->selector());
  }
  ShouldNotReachHere();
  // return nm ? (LookupKey*)&nm->key : LookupKey::allocate(klass, _method->selector()); 
  //                    // potential bug -- is key correct?  (super sends) -- fix this
  return NULL;
}

methodOop RInlinedScope::method() const { return desc->method(); }

bool RScope::wasNeverExecuted() const {
  methodOop m = method();
  symbolOop sel = m->selector();
  if (InliningPolicy::isInterpreterPredictedSmiSelector(sel) ||
      InliningPolicy::isInterpreterPredictedBoolSelector(sel)) {
    // predicted methods aren't called by interpreter if prediction succeeds
    return false;
  } else {
    return m->was_never_executed();
  }
}


// equivalent: test whether receiver scope and argument (a InlinedScope or a LookupKey) denote the same source-level scope

bool RInterpretedScope::equivalent(LookupKey* l) const {
  return _key->equal(l);
}
  
bool RInterpretedScope::equivalent(InlinedScope* s) const {
  return _key->equal(s->key());
}
  
bool RInlinedScope::equivalent(LookupKey* l) const {
  return desc->l_equivalent(l);
}
  
bool RInlinedScope::equivalent(InlinedScope* s) const {
  if (!s->isInlinedScope()) return false;
  InlinedScope* ss = (InlinedScope*)s;
  // don't use ss->rscope because it may not be set yet; but ss's sender
  // must have an rscope if ss is equivalent to this.
  return ss->senderBCI() == desc->senderBCI() &&
         ss->sender()->rscope == sender();
}
  
bool RPICScope::equivalent(InlinedScope* s) const {
  Unused(s);
  // an RPICScope represents a non-inlined scope, so it can't be equivalent
  // to any InlinedScope
  return false;
}

bool RPICScope::equivalent(LookupKey* l) const {
  if (desc != NULL) return desc->l_equivalent(l);   // compiled case
  assert(!_sd->isSuperSend(), "this code probably doesn't work for super sends");
  return klass == l->klass() && _method->selector() == l->selector();
}
  
RScope* RNonDummyScope::subScope(int bci, LookupKey* k) const {
  // return the subscope matching the lookup
  assert(bci >= 0 && bci < ncodes, "bci out of range");
  GrowableArray<RScope*>* list = _subScopes[bci];
  if (list == NULL) return new RNullScope;
  for (int i = 0; i < list->length(); i++) {
    RScope* rs = list->at(i);
    if (rs->equivalent(k))
      return rs;
  }
  return new RNullScope;
}

GrowableArray<RScope*>* RNonDummyScope::subScopes(int bci) const {
  // return all subscopes at bci
  assert(bci >= 0 && bci < ncodes, "bci out of range");
  GrowableArray<RScope*>* list = _subScopes[bci];
  if (list == NULL) return new GrowableArray<RScope*>(1);
  return list;
}

bool RNonDummyScope::hasSubScopes(int bci) const {
  assert(bci >= 0 && bci < ncodes, "bci out of range");
  return _subScopes[bci] != NULL;
}

void RNonDummyScope::addScope(int bci, RScope* s) {
  assert(bci >= 0 && bci < ncodes, "bci out of range");
  if (_subScopes[bci] == NULL) _subScopes[bci] = new GrowableArray<RScope*>(5);
  assert(!_subScopes[bci]->contains(s), "already there");
  // remove uninlineble markers if real scopes are added
  if (_subScopes[bci]->length() == 1 && _subScopes[bci]->first()->isUninlinableScope()) {
    _subScopes[bci]->pop();
  }
  _subScopes[bci]->append(s);
}

bool RInterpretedScope::isUncommonAt(int bci) const { return DeferUncommonBranches; }

bool RNonDummyScope::isUncommonAt(int bci) const {
  if (_subScopes[bci]) {
    RScope* s = _subScopes[bci]->first();
    if (s && s->isUntakenScope()) {
      // send was never executed - make it uncommon
      return true;
    }
  }
  return false;
}

bool RNonDummyScope::isNotUncommonAt(int bci) const {
  assert(bci >= 0 && bci < ncodes, "bci out of range");

  // check if program got uncommon trap in the past
  for (int i = 0; i < uncommon.length(); i++) {
    if (uncommon.at(i)->bci() == bci) return true;
  }

  if (_subScopes[bci]) {
    RScope* s = _subScopes[bci]->first();
    if (s && !s->isUntakenScope()) {
      // send was executed at least once - don't make it uncommon
      return true;
    }
  }
  return false;
}

Expr* RScope::receiverExpr(PReg* p) const {
  // guess that true/false map really means true/false object
  // (gives more efficient testing code)
  klassOop k = receiverKlass();
  if (k == trueObj->klass()) {
    return new ConstantExpr(trueObj, p, NULL);
  } else if (k == falseObj->klass()) {
    return new ConstantExpr(falseObj, p, NULL);
  } else {
    return new KlassExpr(k, p, NULL);
  }
}

Expr* RUntakenScope::receiverExpr(PReg* p) const {
  return new UnknownExpr(p, NULL, true);
}

bool RInlinedScope::isLite() const      { return desc->is_lite(); }
bool RPICScope::isLite() const  { return desc && desc->is_lite(); }
klassOop RInterpretedScope::receiverKlass() const { return _key->klass(); }
klassOop RInlinedScope::receiverKlass() const { return desc->selfKlass(); }

void RNonDummyScope::unify(RNonDummyScope* s) {
  assert(ncodes == s->ncodes, "should be the same");
  for (int i = 0; i < ncodes; i++) {
    _subScopes[i] = s->_subScopes[i];
    if (_subScopes[i]) {
      for (int j = _subScopes[i]->length() - 1; j >= 0; j--) {
        _subScopes[i]->at(j)->_sender = this;
      }
    }
  }
}

void RPICScope::unify(RNonDummyScope* s) {
  RNonDummyScope::unify(s);
  if (s->isPICScope()) {
    uncommon.appendAll(&((RPICScope*)s)->uncommon);
  }

}

const int UntrustedPICLimit = 2;
const int PICTrustLimit = 2;
  
static void getCallees(const nmethod* nm, 
                       GrowableArray<PcDesc*>*&   taken_uncommon,
                       GrowableArray<PcDesc*>*& untaken_uncommon,
                       GrowableArray<PcDesc*>*& uninlinable,
                       GrowableArray<RNonDummyScope*>*& sends, 
                       bool trusted, 
                       int level) {
  // return a list of all uncommon branches of nm, plus a list
  // of all nmethods called by nm (in the form of PICScopes)
  // all lists are sorted by scope (biggest offset first)
  if (theCompiler && CompilerDebug) {
    cout(PrintRScopes)->print("%*s*searching nm %#lx \"%s\" (%strusted; %ld callers)\n", 2 * level, "",
                              nm, nm->key.selector()->as_string(), trusted ? "" : "not ", nm->ncallers());
  }
  taken_uncommon = new GrowableArray<PcDesc*>(1);
  untaken_uncommon = new GrowableArray<PcDesc*>(16);
  uninlinable = new GrowableArray<PcDesc*>(16);
  sends = new GrowableArray<RNonDummyScope*>(10);
  relocIterator iter(nm);
  while (iter.next()) {
    if (iter.type() == relocInfo::uncommon_type) {
      GrowableArray<PcDesc*>* l = iter.wasUncommonTrapExecuted() ? taken_uncommon : untaken_uncommon;
      l->append(nm->containingPcDesc((char*)iter.word_addr()));
    }
  }

  taken_uncommon->sort(&compare_pcDescs);
  untaken_uncommon->sort(&compare_pcDescs);

  if (TypeFeedback) {
    relocIterator iter(nm);
    while (iter.next()) {
      if (iter.type() != relocInfo::ic_type)  continue;
      CompiledIC* sd = iter.ic();
      PcDesc* p = nm->containingPcDesc((char*)sd);
      if (sd->wasNeverExecuted()) {
        // this send was never taken
        sends->append(new RUntakenScope(NULL, p, false));
      } else if (sd->isUninlinable() || sd->isMegamorphic()) {
        // don't inline this send
        uninlinable->append(p);
      } else {
        bool useInfo  = trusted || sd->ntargets() <= UntrustedPICLimit;
        if (useInfo) {
          CompiledIC_Iterator it(sd);
          while (!it.at_end()) {
            nmethod* callee = it.compiled_method();
            methodOop m = it.interpreted_method();
            ScopeDesc* desc;
            int count;
            if (callee != NULL) {
              // compiled target
              desc = callee->scopes()->root();
              count = callee->invocation_count() / max(1, callee->ncallers());
            } else {
              // interpreted target
              desc = NULL;
              count = m->invocation_count();
            }
            sends->append(new RPICScope(nm, p, sd, it.klass(), desc, callee, m, count, level, trusted));
            it.advance();
          }
        } else if (theCompiler && CompilerDebug) {
          cout(PrintRScopes)->print("%*s*not trusting PICs in sd %#lx \"%s\" (%ld cases)\n",
                                    2*level, "", sd, sd->selector()->as_string(), sd->ntargets());
        }
      }
    }
    sends->sort(&RPICScope::compare);
    uninlinable->sort(&compare_pcDescs);
  }
}

RNonDummyScope* RNonDummyScope::constructRScopes(const nmethod* nm, bool trusted, int level) {
  // construct nm's RScope tree and return the root
  // level > 0 means recursive invocation through a RPICScope (level
  // is the recursion depth); trusted means PICs info is considered accurate
  RNonDummyScope* current = NULL;
  RNonDummyScope* root = NULL;
  GrowableArray<PcDesc*>* taken_uncommon;
  GrowableArray<PcDesc*>* untaken_uncommon;
  GrowableArray<PcDesc*>* uninlinable;
  GrowableArray<RNonDummyScope*>* sends;
  getCallees(nm, taken_uncommon, untaken_uncommon, uninlinable, sends, trusted, level);

  // visit each scope in the debug info and enter it into the tree
  FOR_EACH_SCOPE(nm->scopes(), s) {
    // search s' sender RScope
    ScopeDesc* sender = s->sender();
    for (RNonDummyScope* rsender = current; rsender; rsender = rsender->sender()) {
      if (rsender->isInlinedScope() &&
          ((RInlinedScope*)rsender)->desc->is_equal(sender))
        break;
    }
    int bci = sender ? s->senderBCI() : IllegalBCI;
    current = new RInlinedScope((RInlinedScope*)rsender, bci, nm, s, level);
    if (!root) {
      root = current;
      root->nsends = nm->invocation_count();
    }

    // enter bcis with taken uncommon branches
    while (taken_uncommon->nonEmpty() && taken_uncommon->top()->scope == s->offset()) {
      current->uncommon.push(new RUncommonBranch(current, taken_uncommon->pop()));
    }
    // enter info from PICs
    while (sends->nonEmpty() && sends->top()->scopeID() == s->offset()) {
      RNonDummyScope* s = sends->pop();
      s->_sender = current; 
      current->addScope(s->senderBCI(), s);
    }
    // enter untaken uncommon branches
    PcDesc* u;
    while (untaken_uncommon->nonEmpty() && (u = untaken_uncommon->top())->scope == s->offset()) {
      new RUntakenScope(current, u, true);    // will add it as subscope of current
      untaken_uncommon->pop();
    }
    // enter uninlinable sends
    while (uninlinable->nonEmpty() && (u = uninlinable->top())->scope == s->offset()) {
      // only add uninlinable markers for sends that have no inlined cases
      int bci = u->byteCode;
      if (!current->hasSubScopes(bci)) {
        new RUninlinableScope(current, bci);    // will add it as subscope of current
      }
      uninlinable->pop();
    }
  }
  assert(sends           ->isEmpty(), "sends should have been connected to rscopes");
  assert(  taken_uncommon->isEmpty(), "taken uncommon branches should have been connected to rscopes");
  assert(untaken_uncommon->isEmpty(), "untaken uncommon branches should have been connected to rscopes");
  assert(uninlinable     ->isEmpty(), "uninlinable sends should have been connected to rscopes");
  return root;
}

void RNonDummyScope::constructSubScopes(bool trusted) {
  // construct all our (immediate) subscopes
  methodOop m = method();
  if (m->is_accessMethod()) return;
  CodeIterator iter(m);
  do {
    RNonDummyScope* s = NULL;
    InterpretedIC* ic = iter.ic();
    switch (iter.send()) {
      case Bytecodes::interpreted_send:
      case Bytecodes::compiled_send   :
      case Bytecodes::predicted_send  :
      case Bytecodes::accessor_send   :
      case Bytecodes::polymorphic_send:
      case Bytecodes::primitive_send  :
        { for (InterpretedIC_Iterator it(ic); !it.at_end(); it.advance()) {
            if (it.is_compiled()) {
              nmethod* nm = it.compiled_method();
              RNonDummyScope* s = constructRScopes(nm, trusted && trustPICs(m), _level + 1);
              addScope(iter.bci(), s);
            } else {
              methodOop m = it.interpreted_method();
              LookupKey* k = LookupKey::allocate(it.klass(), it.selector());
              new RInterpretedScope(this, iter.bci(), k, m, _level + 1, trusted && trustPICs(m)); 
              // NB: constructor adds callee to our subScope list
            }
          }
        }
        break;
      case Bytecodes::megamorphic_send:
        new RUninlinableScope(this, iter.bci());  // constructor adds callee to our subScope list
        break;
      case Bytecodes::no_send         :
        break;
      default:
        fatal1("unexpected send type %d", iter.send());
    }
  } while (iter.advance());
}


bool RNonDummyScope::trustPICs(methodOop m) {
  // should the PICs in m be trusted?
  symbolOop sel = m->selector();
  if (sel == vmSymbols::plus() || sel == vmSymbols::minus() ||
      sel == vmSymbols::multiply() || sel == vmSymbols::divide()) {
    // code space optimization: try to avoid unnecessary mixed-type arithmetic
    return false;
  } else {
    return true;        // can't easily determine number of callers
  }
}

bool RPICScope::trustPICs(const nmethod* nm) {
  // should the PICs in nm be trusted?
  int invoc = nm->invocation_count();
  if (invoc < MinInvocationsBeforeTrust) return false;
  int ncallers = nm->ncallers();
  symbolOop sel = nm->key.selector();
  if (sel == vmSymbols::plus() || sel == vmSymbols::minus() ||
      sel == vmSymbols::multiply() || sel == vmSymbols::divide()) {
    // code space optimization: try to avoid unnecessary mixed-type arithmetic
    return ncallers <= 1;
  } else {
    return ncallers <= PICTrustLimit;
  }
}

void RPICScope::extend() {
  // try to follow PIC info one level deeper (i.e. extend rscope tree)
  if (extended) return;
  if (nm && !nm->isZombie()) {
    // search the callee for type info
    RNonDummyScope* s = constructRScopes(nm, trusted && trustPICs(nm), _level + 1);
    // s and receiver represent the same scope - unify them
    unify(s);
  } else {
    constructSubScopes(false);    // search interpreted inline caches but don't trust their info
  }
  extended = true;
}

void RInterpretedScope::extend() {
  // try to follow PIC info one level deeper (i.e. extend rscope tree)
  if (!extended) {
    // search the inline caches for type info
    constructSubScopes(trusted);
    if (PrintRScopes) printTree(_senderBCI, _level);
  }
  extended = true;
}

void RScope::print() { 
  std->print("; sender: %#lx@%ld; count %ld\n", PrintHexAddresses ? _sender : 0, _senderBCI, nsends);
}

void RNonDummyScope::printSubScopes() const {
  for (int i = 0; i < ncodes && _subScopes[i] == NULL; i++) ;
  if (i < ncodes) {
    std->print("{ ");
    for (i = 0; i < ncodes; i++) {
      std->print("%#lx ", PrintHexAddresses ? _subScopes[i] : 0);
    }
    std->print("}");
  } else {
    std->print("none");
  }
}
  
void RInterpretedScope::print_short() {
  std->print("((RInterpretedScope*)%#lx) \"%s\" #%ld", PrintHexAddresses ? this : 0, _key->print_string(), nsends);
}
  
void RInlinedScope::print_short() {
  std->print("((RInlinedScope*)%#lx) \"%s\" #%ld", PrintHexAddresses ? this : 0, desc->selector()->as_string(), nsends);
}
  
void RInlinedScope::print() {
  print_short();
  std->print(": scope %#lx; subScopes: ", PrintHexAddresses ? desc : 0);
  printSubScopes();
  if (uncommon.nonEmpty()) { std->print("; uncommon "); uncommon.print(); }
  RScope::print();
}

void RPICScope::print_short() {
  std->print("((RPICScope*)%#lx) \"%s\" #%ld", PrintHexAddresses ? this : 0, method()->selector()->as_string(), nsends);
}
  
void RPICScope::print() {
  print_short();
  std->print(": IC %#lx; subScopes: ", PrintHexAddresses ? _sd : 0);
  printSubScopes();
  if (uncommon.nonEmpty()) { std->print("; uncommon "); uncommon.print(); }
}

void RUntakenScope::print_short() {
  std->print("((RUntakenScope*)%#lx) \"%s\"", PrintHexAddresses ? this : 0);
}

void RUntakenScope::print() {
  print_short();
  assert(!*_subScopes, "should have no subscopes");
  assert(uncommon.isEmpty(), "should have no uncommon branches");
}

void RUncommonBranch::print() {
  std->print("((RUncommonScope*)%#lx) : %#lx@%ld\n", PrintHexAddresses ? this : 0, PrintHexAddresses ? scope : 0, bci());
}

void RUninlinableScope::print_short()   { std->print("((RUninlinableScope*)%#lx)", PrintHexAddresses ? this : 0); }
void RNullScope::print_short()          { std->print("((RNullScope*)%#lx)", PrintHexAddresses ? this : 0); }

void RNullScope::printTree(int bci, int level) const { }

void RScope::printTree(int bci, int level) const {
  std->print("%*s%3ld: ", level * 2, "", bci); ((RScope*)this)->print_short(); std->print("\n");
}

void RNonDummyScope::printTree(int senderBCI, int level) const {
  RScope::printTree(senderBCI, level);
  int u = 0;          // current position in uncommon
  for (int bci = 0; bci < ncodes; bci++) {
    if (_subScopes[bci]) {
      for (int j = 0; j < _subScopes[bci]->length(); j++) {
        _subScopes[bci]->at(j)->printTree(bci, level + 1);
      }
    }
    for (int j = u; j < uncommon.length() && uncommon.at(j)->bci() < bci; u++, j++) ;
    if (j < uncommon.length() && uncommon.at(j)->bci() == bci) {
      std->print("  %*s%3ld: uncommon\n", level * 2, "", bci);
    }
  }
}

void RDatabaseScope::print() {
  print_short();
  printSubScopes();
}

void RDatabaseScope::print_short() {
  std->print("((RDatabaseScope*)%#lx)  \"%s\"", PrintHexAddresses ? this : 0, _key->print_string());
}

bool RDatabaseScope::equivalent(InlinedScope* s) const {
  Unimplemented();
  return false;
}

bool RDatabaseScope::equivalent(LookupKey* l) const {
  return _key->equal(l);
}

bool RDatabaseScope::isUncommonAt(int bci) const {
  // if the DB has an uncommon branch at bci, treat it as untaken
  return _uncommon->at(bci);  
}

bool RDatabaseScope::isNotUncommonAt(int bci) const {
  // if there's no uncommon branch in the DB, don't use it here either
  return !_uncommon->at(bci);  
}

int  RInlinedScope::inlining_database_size() {
  int result = 1; // Count this node

  for (int i = 0; i < ncodes; i++) {
    if (_subScopes[i]) {
      for (int j = 0; j < _subScopes[i]->length(); j++) {
        result += _subScopes[i]->at(j)->inlining_database_size();
      }
    }
  }
  return result;
}



// don't file out PIC scopes in the output since they're not inlined into the current nmethod;
// same for interpreted scopes 

inline PcDesc* next_uncommon(int scope, int u, GrowableArray<PcDesc*>* uncommon) {
  if (uncommon == NULL || u >= uncommon->length()) return NULL;   // none left
  PcDesc* pc = uncommon->at(u);
  return (pc->scope == scope) ? pc : NULL;
}

void RUninlinableScope::print_inlining_database_on(outputStream* st, GrowableArray<PcDesc*>* uncommon, int bci, int level) {
  // not necessary to actually write out this info since DB-driven compilation won't inline anything not inlined in DB
  // st->print_cr("%*s%d uninlinable", level * 2, "", bci);
}

void RInlinedScope::print_inlining_database_on(outputStream* st, GrowableArray<PcDesc*>* uncommon, int bci, int level) {
  // File out level and bci
  if (bci != -1) {
    st->print("%*s%d ", level * 2, "", bci);
  }

  LookupKey* k = key();
  k->print_inlining_database_on(st);
  st->cr();

  // find scope in uncommon list
  int scope = desc->offset();
  for (int u = 0; uncommon && u < uncommon->length() - 1 && uncommon->at(u)->scope < scope; u++) ;
  PcDesc* current_uncommon = next_uncommon(scope, u, uncommon);

  // File out subscopes
  for (int i = 0; i < ncodes; i++) {
    if (_subScopes[i]) {
      for (int j = 0; j < _subScopes[i]->length(); j++) {
        _subScopes[i]->at(j)->print_inlining_database_on(st, uncommon, i, level + 1);
      }
    }
    if (current_uncommon && current_uncommon->byteCode == i) {
      // nmethod has an uncommon branch at this bci
      st->print_cr("%*s%d uncommon", (level + 1) * 2, "", i);
      // advance to next uncommon branch
      u++;
      current_uncommon = next_uncommon(scope, u, uncommon);
    }
  }
}

# endif

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