6986046: C1 valuestack cleanup

Summary: fixes an historical oddity in C1 with inlining where all of the expression stacks are kept in the topmost ValueStack instead of being in their respective ValueStacks.
Reviewed-by: never
Contributed-by: NChristian Wimmer <cwimmer@uci.edu>

src/cpu/sparc/vm/c1_CodeStubs_sparc.cpp

@@ -32,6 +32,7 @@ RangeCheckStub::RangeCheckStub(CodeEmitInfo* info, LIR_Opr index,
   : _throw_index_out_of_bounds_exception(throw_index_out_of_bounds_exception)
   , _index(index)
 {
+  assert(info != NULL, "must have info");
   _info = new CodeEmitInfo(info);
 }
 

src/cpu/sparc/vm/c1_LIRGenerator_sparc.cpp

@@ -311,7 +311,7 @@ void LIRGenerator::store_stack_parameter (LIR_Opr item, ByteSize offset_from_sp)
 
 
 void LIRGenerator::do_StoreIndexed(StoreIndexed* x) {
-  assert(x->is_root(),"");
+  assert(x->is_pinned(),"");
   bool needs_range_check = true;
   bool use_length = x->length() != NULL;
   bool obj_store = x->elt_type() == T_ARRAY || x->elt_type() == T_OBJECT;
@@ -386,7 +386,7 @@ void LIRGenerator::do_StoreIndexed(StoreIndexed* x) {
 
 
 void LIRGenerator::do_MonitorEnter(MonitorEnter* x) {
-  assert(x->is_root(),"");
+  assert(x->is_pinned(),"");
   LIRItem obj(x->obj(), this);
   obj.load_item();
 
@@ -398,7 +398,7 @@ void LIRGenerator::do_MonitorEnter(MonitorEnter* x) {
 
   CodeEmitInfo* info_for_exception = NULL;
   if (x->needs_null_check()) {
-    info_for_exception = state_for(x, x->lock_stack_before());
+    info_for_exception = state_for(x);
   }
 
   // this CodeEmitInfo must not have the xhandlers because here the
@@ -409,7 +409,7 @@ void LIRGenerator::do_MonitorEnter(MonitorEnter* x) {
 
 
 void LIRGenerator::do_MonitorExit(MonitorExit* x) {
-  assert(x->is_root(),"");
+  assert(x->is_pinned(),"");
   LIRItem obj(x->obj(), this);
   obj.dont_load_item();
 
@@ -871,10 +871,11 @@ void LIRGenerator::do_NewInstance(NewInstance* x) {
   // This instruction can be deoptimized in the slow path : use
   // O0 as result register.
   const LIR_Opr reg = result_register_for(x->type());
-
+#ifndef PRODUCT
   if (PrintNotLoaded && !x->klass()->is_loaded()) {
-    tty->print_cr("   ###class not loaded at new bci %d", x->bci());
+    tty->print_cr("   ###class not loaded at new bci %d", x->printable_bci());
   }
+#endif
   CodeEmitInfo* info = state_for(x, x->state());
   LIR_Opr tmp1 = FrameMap::G1_oop_opr;
   LIR_Opr tmp2 = FrameMap::G3_oop_opr;
@@ -1018,7 +1019,7 @@ void LIRGenerator::do_CheckCast(CheckCast* x) {
   obj.load_item();
   LIR_Opr out_reg = rlock_result(x);
   CodeStub* stub;
-  CodeEmitInfo* info_for_exception = state_for(x, x->state()->copy_locks());
+  CodeEmitInfo* info_for_exception = state_for(x);
 
   if (x->is_incompatible_class_change_check()) {
     assert(patching_info == NULL, "can't patch this");

src/cpu/x86/vm/c1_CodeStubs_x86.cpp

@@ -83,7 +83,8 @@ RangeCheckStub::RangeCheckStub(CodeEmitInfo* info, LIR_Opr index,
   : _throw_index_out_of_bounds_exception(throw_index_out_of_bounds_exception)
   , _index(index)
 {
-  _info = info == NULL ? NULL : new CodeEmitInfo(info);
+  assert(info != NULL, "must have info");
+  _info = new CodeEmitInfo(info);
 }
 
 

src/cpu/x86/vm/c1_LIRGenerator_x86.cpp

@@ -107,7 +107,7 @@ bool LIRGenerator::can_store_as_constant(Value v, BasicType type) const {
     return false;
   }
   Constant* c = v->as_Constant();
-  if (c && c->state() == NULL) {
+  if (c && c->state_before() == NULL) {
     // constants of any type can be stored directly, except for
     // unloaded object constants.
     return true;
@@ -250,7 +250,7 @@ void LIRGenerator::store_stack_parameter (LIR_Opr item, ByteSize offset_from_sp)
 
 
 void LIRGenerator::do_StoreIndexed(StoreIndexed* x) {
-  assert(x->is_root(),"");
+  assert(x->is_pinned(),"");
   bool needs_range_check = true;
   bool use_length = x->length() != NULL;
   bool obj_store = x->elt_type() == T_ARRAY || x->elt_type() == T_OBJECT;
@@ -325,7 +325,7 @@ void LIRGenerator::do_StoreIndexed(StoreIndexed* x) {
 
 
 void LIRGenerator::do_MonitorEnter(MonitorEnter* x) {
-  assert(x->is_root(),"");
+  assert(x->is_pinned(),"");
   LIRItem obj(x->obj(), this);
   obj.load_item();
 
@@ -341,7 +341,7 @@ void LIRGenerator::do_MonitorEnter(MonitorEnter* x) {
 
   CodeEmitInfo* info_for_exception = NULL;
   if (x->needs_null_check()) {
-    info_for_exception = state_for(x, x->lock_stack_before());
+    info_for_exception = state_for(x);
   }
   // this CodeEmitInfo must not have the xhandlers because here the
   // object is already locked (xhandlers expect object to be unlocked)
@@ -352,7 +352,7 @@ void LIRGenerator::do_MonitorEnter(MonitorEnter* x) {
 
 
 void LIRGenerator::do_MonitorExit(MonitorExit* x) {
-  assert(x->is_root(),"");
+  assert(x->is_pinned(),"");
 
   LIRItem obj(x->obj(), this);
   obj.dont_load_item();
@@ -984,9 +984,11 @@ void LIRGenerator::do_Convert(Convert* x) {
 
 
 void LIRGenerator::do_NewInstance(NewInstance* x) {
+#ifndef PRODUCT
   if (PrintNotLoaded && !x->klass()->is_loaded()) {
-    tty->print_cr("   ###class not loaded at new bci %d", x->bci());
+    tty->print_cr("   ###class not loaded at new bci %d", x->printable_bci());
   }
+#endif
   CodeEmitInfo* info = state_for(x, x->state());
   LIR_Opr reg = result_register_for(x->type());
   LIR_Opr klass_reg = new_register(objectType);
@@ -1127,7 +1129,7 @@ void LIRGenerator::do_CheckCast(CheckCast* x) {
   obj.load_item();
 
   // info for exceptions
-  CodeEmitInfo* info_for_exception = state_for(x, x->state()->copy_locks());
+  CodeEmitInfo* info_for_exception = state_for(x);
 
   CodeStub* stub;
   if (x->is_incompatible_class_change_check()) {

src/share/vm/c1/c1_CFGPrinter.cpp

@@ -174,31 +174,6 @@ void CFGPrinterOutput::print_state(BlockBegin* block) {
   int index;
   Value value;
 
-  if (state->stack_size() > 0) {
-    print_begin("stack");
-    print("size %d", state->stack_size());
-
-    for_each_stack_value(state, index, value) {
-      ip.print_phi(index, value, block);
-      print_operand(value);
-      output()->cr();
-    }
-
-    print_end("stack");
-  }
-
-  if (state->locks_size() > 0) {
-    print_begin("locks");
-    print("size %d", state->locks_size());
-
-    for_each_lock_value(state, index, value) {
-      ip.print_phi(index, value, block);
-      print_operand(value);
-      output()->cr();
-    }
-    print_end("locks");
-  }
-
   for_each_state(state) {
     print_begin("locals");
     print("size %d", state->locals_size());
@@ -210,6 +185,33 @@ void CFGPrinterOutput::print_state(BlockBegin* block) {
       output()->cr();
     }
     print_end("locals");
+
+    if (state->stack_size() > 0) {
+      print_begin("stack");
+      print("size %d", state->stack_size());
+      print("method \"%s\"", method_name(state->scope()->method()));
+
+      for_each_stack_value(state, index, value) {
+        ip.print_phi(index, value, block);
+        print_operand(value);
+        output()->cr();
+      }
+
+      print_end("stack");
+    }
+
+    if (state->locks_size() > 0) {
+      print_begin("locks");
+      print("size %d", state->locks_size());
+      print("method \"%s\"", method_name(state->scope()->method()));
+
+      for_each_lock_value(state, index, value) {
+        ip.print_phi(index, value, block);
+        print_operand(value);
+        output()->cr();
+      }
+      print_end("locks");
+    }
   }
 
   print_end("states");
@@ -230,7 +232,8 @@ void CFGPrinterOutput::print_HIR(Value instr) {
   if (instr->is_pinned()) {
     output()->put('.');
   }
-  output()->print("%d %d ", instr->bci(), instr->use_count());
+
+  output()->print("%d %d ", instr->printable_bci(), instr->use_count());
 
   print_operand(instr);
 
@@ -271,7 +274,7 @@ void CFGPrinterOutput::print_block(BlockBegin* block) {
   print("name \"B%d\"", block->block_id());
 
   print("from_bci %d", block->bci());
-  print("to_bci %d", (block->end() == NULL ? -1 : block->end()->bci()));
+  print("to_bci %d", (block->end() == NULL ? -1 : block->end()->printable_bci()));
 
   output()->indent();
   output()->print("predecessors ");

src/share/vm/c1/c1_Canonicalizer.cpp

@@ -205,7 +205,7 @@ void Canonicalizer::do_StoreField     (StoreField*      x) {
     // limit this optimization to current block
     if (value != NULL && in_current_block(conv)) {
       set_canonical(new StoreField(x->obj(), x->offset(), x->field(), value, x->is_static(),
-                                       x->lock_stack(), x->state_before(), x->is_loaded(), x->is_initialized()));
+                                       x->state_before(), x->is_loaded(), x->is_initialized()));
       return;
     }
   }
@@ -256,7 +256,7 @@ void Canonicalizer::do_StoreIndexed   (StoreIndexed*    x) {
     // limit this optimization to current block
     if (value != NULL && in_current_block(conv)) {
       set_canonical(new StoreIndexed(x->array(), x->index(), x->length(),
-                                     x->elt_type(), value, x->lock_stack()));
+                                     x->elt_type(), value, x->state_before()));
       return;
     }
   }
@@ -667,7 +667,7 @@ void Canonicalizer::do_If(If* x) {
             }
           }
           set_canonical(canon);
-          set_bci(cmp->bci());
+          set_bci(cmp->state_before()->bci());
         }
       }
     } else if (l->as_InstanceOf() != NULL) {
@@ -685,7 +685,7 @@ void Canonicalizer::do_If(If* x) {
         set_canonical(new Goto(is_inst_sux, x->state_before(), x->is_safepoint()));
       } else {
         // successors differ => simplify to: IfInstanceOf
-        set_canonical(new IfInstanceOf(inst->klass(), inst->obj(), true, inst->bci(), is_inst_sux, no_inst_sux));
+        set_canonical(new IfInstanceOf(inst->klass(), inst->obj(), true, inst->state_before()->bci(), is_inst_sux, no_inst_sux));
       }
     }
   } else if (rt == objectNull && (l->as_NewInstance() || l->as_NewArray())) {

src/share/vm/c1/c1_Compilation.hpp

@@ -22,7 +22,6 @@
  *
  */
 
-class BlockBegin;
 class CompilationResourceObj;
 class XHandlers;
 class ExceptionInfo;

src/share/vm/c1/c1_GraphBuilder.hpp

@@ -58,9 +58,6 @@ class GraphBuilder VALUE_OBJ_CLASS_SPEC {
     // BlockEnds.
     BlockBegin*  _continuation;
 
-    // Without return value of inlined method on stack
-    ValueStack*  _continuation_state;
-
     // Was this ScopeData created only for the parsing and inlining of
     // a jsr?
     bool         _parsing_jsr;
@@ -125,14 +122,10 @@ class GraphBuilder VALUE_OBJ_CLASS_SPEC {
     void set_stream(ciBytecodeStream* stream)      { _stream = stream;          }
 
     intx max_inline_size() const                   { return _max_inline_size;   }
-    int  caller_stack_size() const;
 
     BlockBegin* continuation() const               { return _continuation;      }
     void set_continuation(BlockBegin* cont)        { _continuation = cont;      }
 
-    ValueStack* continuation_state() const         { return _continuation_state; }
-    void set_continuation_state(ValueStack* s)     { _continuation_state = s; }
-
     // Indicates whether this ScopeData was pushed only for the
     // parsing and inlining of a jsr
     bool parsing_jsr() const                       { return _parsing_jsr;       }
@@ -163,7 +156,6 @@ class GraphBuilder VALUE_OBJ_CLASS_SPEC {
 
   // for all GraphBuilders
   static bool       _can_trap[Bytecodes::number_of_java_codes];
-  static bool       _is_async[Bytecodes::number_of_java_codes];
 
   // for each instance of GraphBuilder
   ScopeData*        _scope_data;                 // Per-scope data; used for inlining
@@ -179,7 +171,6 @@ class GraphBuilder VALUE_OBJ_CLASS_SPEC {
   // for each call to connect_to_end; can also be set by inliner
   BlockBegin*       _block;                      // the current block
   ValueStack*       _state;                      // the current execution state
-  ValueStack*       _exception_state;            // state that will be used by handle_exception
   Instruction*      _last;                       // the last instruction added
   bool              _skip_block;                 // skip processing of the rest of this block
 
@@ -194,8 +185,6 @@ class GraphBuilder VALUE_OBJ_CLASS_SPEC {
   ValueStack*       state() const                { return _state; }
   void              set_state(ValueStack* state) { _state = state; }
   IRScope*          scope() const                { return scope_data()->scope(); }
-  ValueStack*       exception_state() const      { return _exception_state; }
-  void              set_exception_state(ValueStack* s) { _exception_state = s; }
   ciMethod*         method() const               { return scope()->method(); }
   ciBytecodeStream* stream() const               { return scope_data()->stream(); }
   Instruction*      last() const                 { return _last; }
@@ -230,7 +219,7 @@ class GraphBuilder VALUE_OBJ_CLASS_SPEC {
   void load_indexed (BasicType type);
   void store_indexed(BasicType type);
   void stack_op(Bytecodes::Code code);
-  void arithmetic_op(ValueType* type, Bytecodes::Code code, ValueStack* lock_stack = NULL);
+  void arithmetic_op(ValueType* type, Bytecodes::Code code, ValueStack* state_before = NULL);
   void negate_op(ValueType* type);
   void shift_op(ValueType* type, Bytecodes::Code code);
   void logic_op(ValueType* type, Bytecodes::Code code);
@@ -267,12 +256,8 @@ class GraphBuilder VALUE_OBJ_CLASS_SPEC {
   Instruction* append_split(StateSplit* instr);
 
   // other helpers
-  static bool is_async(Bytecodes::Code code) {
-    assert(0 <= code && code < Bytecodes::number_of_java_codes, "illegal bytecode");
-    return _is_async[code];
-  }
   BlockBegin* block_at(int bci)                  { return scope_data()->block_at(bci); }
-  XHandlers* handle_exception(int bci);
+  XHandlers* handle_exception(Instruction* instruction);
   void connect_to_end(BlockBegin* beg);
   void null_check(Value value);
   void eliminate_redundant_phis(BlockBegin* start);
@@ -283,7 +268,28 @@ class GraphBuilder VALUE_OBJ_CLASS_SPEC {
 
   void kill_all();
 
-  ValueStack* lock_stack();
+  // use of state copy routines (try to minimize unnecessary state
+  // object allocations):
+
+  // - if the instruction unconditionally needs a full copy of the
+  // state (for patching for example), then use copy_state_before*
+
+  // - if the instruction needs a full copy of the state only for
+  // handler generation (Instruction::needs_exception_state() returns
+  // false) then use copy_state_exhandling*
+
+  // - if the instruction needs either a full copy of the state for
+  // handler generation and a least a minimal copy of the state (as
+  // returned by Instruction::exception_state()) for debug info
+  // generation (that is when Instruction::needs_exception_state()
+  // returns true) then use copy_state_for_exception*
+
+  ValueStack* copy_state_before_with_bci(int bci);
+  ValueStack* copy_state_before();
+  ValueStack* copy_state_exhandling_with_bci(int bci);
+  ValueStack* copy_state_exhandling();
+  ValueStack* copy_state_for_exception_with_bci(int bci);
+  ValueStack* copy_state_for_exception();
 
   //
   // Inlining support
@@ -292,9 +298,7 @@ class GraphBuilder VALUE_OBJ_CLASS_SPEC {
   // accessors
   bool parsing_jsr() const                               { return scope_data()->parsing_jsr();           }
   BlockBegin* continuation() const                       { return scope_data()->continuation();          }
-  ValueStack* continuation_state() const                 { return scope_data()->continuation_state();    }
   BlockBegin* jsr_continuation() const                   { return scope_data()->jsr_continuation();      }
-  int caller_stack_size() const                          { return scope_data()->caller_stack_size();     }
   void set_continuation(BlockBegin* continuation)        { scope_data()->set_continuation(continuation); }
   void set_inline_cleanup_info(BlockBegin* block,
                                Instruction* return_prev,

src/share/vm/c1/c1_IR.cpp

@@ -116,24 +116,6 @@ bool XHandler::equals(XHandler* other) const {
 
 
 // Implementation of IRScope
-
-BlockBegin* IRScope::header_block(BlockBegin* entry, BlockBegin::Flag f, ValueStack* state) {
-  if (entry == NULL) return NULL;
-  assert(entry->is_set(f), "entry/flag mismatch");
-  // create header block
-  BlockBegin* h = new BlockBegin(entry->bci());
-  BlockEnd* g = new Goto(entry, false);
-  h->set_next(g, entry->bci());
-  h->set_end(g);
-  h->set(f);
-  // setup header block end state
-  ValueStack* s = state->copy(); // can use copy since stack is empty (=> no phis)
-  assert(s->stack_is_empty(), "must have empty stack at entry point");
-  g->set_state(s);
-  return h;
-}
-
-
 BlockBegin* IRScope::build_graph(Compilation* compilation, int osr_bci) {
   GraphBuilder gm(compilation, this);
   NOT_PRODUCT(if (PrintValueNumbering && Verbose) gm.print_stats());
@@ -145,12 +127,9 @@ BlockBegin* IRScope::build_graph(Compilation* compilation, int osr_bci) {
 IRScope::IRScope(Compilation* compilation, IRScope* caller, int caller_bci, ciMethod* method, int osr_bci, bool create_graph)
 : _callees(2)
 , _compilation(compilation)
-, _lock_stack_size(-1)
 , _requires_phi_function(method->max_locals())
 {
   _caller             = caller;
-  _caller_bci         = caller == NULL ? -1 : caller_bci;
-  _caller_state       = NULL; // Must be set later if needed
   _level              = caller == NULL ?  0 : caller->level() + 1;
   _method             = method;
   _xhandlers          = new XHandlers(method);
@@ -182,32 +161,6 @@ int IRScope::max_stack() const {
 }
 
 
-void IRScope::compute_lock_stack_size() {
-  if (!InlineMethodsWithExceptionHandlers) {
-    _lock_stack_size = 0;
-    return;
-  }
-
-  // Figure out whether we have to preserve expression stack elements
-  // for parent scopes, and if so, how many
-  IRScope* cur_scope = this;
-  while (cur_scope != NULL && !cur_scope->xhandlers()->has_handlers()) {
-    cur_scope = cur_scope->caller();
-  }
-  _lock_stack_size = (cur_scope == NULL ? 0 :
-                      (cur_scope->caller_state() == NULL ? 0 :
-                       cur_scope->caller_state()->stack_size()));
-}
-
-int IRScope::top_scope_bci() const {
-  assert(!is_top_scope(), "no correct answer for top scope possible");
-  const IRScope* scope = this;
-  while (!scope->caller()->is_top_scope()) {
-    scope = scope->caller();
-  }
-  return scope->caller_bci();
-}
-
 bool IRScopeDebugInfo::should_reexecute() {
   ciMethod* cur_method = scope()->method();
   int       cur_bci    = bci();
@@ -222,37 +175,24 @@ bool IRScopeDebugInfo::should_reexecute() {
 // Implementation of CodeEmitInfo
 
 // Stack must be NON-null
-CodeEmitInfo::CodeEmitInfo(int bci, ValueStack* stack, XHandlers* exception_handlers)
+CodeEmitInfo::CodeEmitInfo(ValueStack* stack, XHandlers* exception_handlers)
   : _scope(stack->scope())
-  , _bci(bci)
   , _scope_debug_info(NULL)
   , _oop_map(NULL)
   , _stack(stack)
   , _exception_handlers(exception_handlers)
-  , _next(NULL)
-  , _id(-1)
   , _is_method_handle_invoke(false) {
   assert(_stack != NULL, "must be non null");
-  assert(_bci == SynchronizationEntryBCI || Bytecodes::is_defined(scope()->method()->java_code_at_bci(_bci)), "make sure bci points at a real bytecode");
 }
 
 
-CodeEmitInfo::CodeEmitInfo(CodeEmitInfo* info, bool lock_stack_only)
+CodeEmitInfo::CodeEmitInfo(CodeEmitInfo* info, ValueStack* stack)
   : _scope(info->_scope)
   , _exception_handlers(NULL)
-  , _bci(info->_bci)
   , _scope_debug_info(NULL)
   , _oop_map(NULL)
+  , _stack(stack == NULL ? info->_stack : stack)
   , _is_method_handle_invoke(info->_is_method_handle_invoke) {
-  if (lock_stack_only) {
-    if (info->_stack != NULL) {
-      _stack = info->_stack->copy_locks();
-    } else {
-      _stack = NULL;
-    }
-  } else {
-    _stack = info->_stack;
-  }
 
   // deep copy of exception handlers
   if (info->_exception_handlers != NULL) {
@@ -273,8 +213,6 @@ void CodeEmitInfo::add_register_oop(LIR_Opr opr) {
   assert(_oop_map != NULL, "oop map must already exist");
   assert(opr->is_single_cpu(), "should not call otherwise");
 
-  int frame_size = frame_map()->framesize();
-  int arg_count = frame_map()->oop_map_arg_count();
   VMReg name = frame_map()->regname(opr);
   _oop_map->set_oop(name);
 }
@@ -383,8 +321,7 @@ class UseCountComputer: public ValueVisitor, BlockClosure {
   void visit(Value* n) {
     // Local instructions and Phis for expression stack values at the
     // start of basic blocks are not added to the instruction list
-    if ((*n)->bci() == -99 && (*n)->as_Local() == NULL &&
-        (*n)->as_Phi() == NULL) {
+    if (!(*n)->is_linked()&& (*n)->can_be_linked()) {
       assert(false, "a node was not appended to the graph");
       Compilation::current()->bailout("a node was not appended to the graph");
     }
@@ -1338,7 +1275,7 @@ void SubstitutionResolver::block_do(BlockBegin* block) {
     // need to remove this instruction from the instruction stream
     if (n->subst() != n) {
       assert(last != NULL, "must have last");
-      last->set_next(n->next(), n->next()->bci());
+      last->set_next(n->next());
     } else {
       last = n;
     }

src/share/vm/c1/c1_IR.hpp

@@ -132,8 +132,6 @@ class IRScope: public CompilationResourceObj {
   // hierarchy
   Compilation*  _compilation;                    // the current compilation
   IRScope*      _caller;                         // the caller scope, or NULL
-  int           _caller_bci;                     // the caller bci of the corresponding (inlined) invoke, or < 0
-  ValueStack*   _caller_state;                   // the caller state, or NULL
   int           _level;                          // the inlining level
   ciMethod*     _method;                         // the corresponding method
   IRScopeList   _callees;                        // the inlined method scopes
@@ -144,15 +142,9 @@ class IRScope: public CompilationResourceObj {
   bool          _monitor_pairing_ok;             // the monitor pairing info
   BlockBegin*   _start;                          // the start block, successsors are method entries
 
-  // lock stack management
-  int           _lock_stack_size;                // number of expression stack elements which, if present,
-                                                 // must be spilled to the stack because of exception
-                                                 // handling inside inlined methods
-
   BitMap        _requires_phi_function;          // bit is set if phi functions at loop headers are necessary for a local variable
 
   // helper functions
-  BlockBegin* header_block(BlockBegin* entry, BlockBegin::Flag f, ValueStack* state);
   BlockBegin* build_graph(Compilation* compilation, int osr_bci);
 
  public:
@@ -162,33 +154,16 @@ class IRScope: public CompilationResourceObj {
   // accessors
   Compilation*  compilation() const              { return _compilation; }
   IRScope*      caller() const                   { return _caller; }
-  int           caller_bci() const               { return _caller_bci; }
-  ValueStack*   caller_state() const             { return _caller_state; }
   int           level() const                    { return _level; }
   ciMethod*     method() const                   { return _method; }
   int           max_stack() const;               // NOTE: expensive
-  int           lock_stack_size() const          {
-    assert(_lock_stack_size != -1, "uninitialized");
-    return _lock_stack_size;
-  }
   BitMap&       requires_phi_function()          { return _requires_phi_function; }
 
-  // mutators
-  // Needed because caller state is not ready at time of IRScope construction
-  void          set_caller_state(ValueStack* state) { _caller_state = state; }
-  // Needed because caller state changes after IRScope construction.
-  // Computes number of expression stack elements whose state must be
-  // preserved in the case of an exception; these may be seen by
-  // caller scopes. Zero when inlining of methods containing exception
-  // handlers is disabled, otherwise a conservative approximation.
-  void          compute_lock_stack_size();
-
   // hierarchy
   bool          is_top_scope() const             { return _caller == NULL; }
   void          add_callee(IRScope* callee)      { _callees.append(callee); }
   int           number_of_callees() const        { return _callees.length(); }
   IRScope*      callee_no(int i) const           { return _callees.at(i); }
-  int           top_scope_bci() const;
 
   // accessors, graph
   bool          is_valid() const                 { return start() != NULL; }
@@ -266,9 +241,6 @@ class CodeEmitInfo: public CompilationResourceObj {
   XHandlers*        _exception_handlers;
   OopMap*           _oop_map;
   ValueStack*       _stack;                      // used by deoptimization (contains also monitors
-  int               _bci;
-  CodeEmitInfo*     _next;
-  int               _id;
   bool              _is_method_handle_invoke;    // true if the associated call site is a MethodHandle call site.
 
   FrameMap*     frame_map() const                { return scope()->compilation()->frame_map(); }
@@ -277,23 +249,10 @@ class CodeEmitInfo: public CompilationResourceObj {
  public:
 
   // use scope from ValueStack
-  CodeEmitInfo(int bci, ValueStack* stack, XHandlers* exception_handlers);
-
-  // used by natives
-  CodeEmitInfo(IRScope* scope, int bci)
-    : _scope(scope)
-    , _bci(bci)
-    , _oop_map(NULL)
-    , _scope_debug_info(NULL)
-    , _stack(NULL)
-    , _exception_handlers(NULL)
-    , _next(NULL)
-    , _id(-1)
-    , _is_method_handle_invoke(false) {
-  }
+  CodeEmitInfo(ValueStack* stack, XHandlers* exception_handlers);
 
   // make a copy
-  CodeEmitInfo(CodeEmitInfo* info, bool lock_stack_only = false);
+  CodeEmitInfo(CodeEmitInfo* info, ValueStack* stack = NULL);
 
   // accessors
   OopMap* oop_map()                              { return _oop_map; }
@@ -301,17 +260,10 @@ class CodeEmitInfo: public CompilationResourceObj {
   IRScope* scope() const                         { return _scope; }
   XHandlers* exception_handlers() const          { return _exception_handlers; }
   ValueStack* stack() const                      { return _stack; }
-  int bci() const                                { return _bci; }
 
   void add_register_oop(LIR_Opr opr);
   void record_debug_info(DebugInformationRecorder* recorder, int pc_offset);
 
-  CodeEmitInfo* next() const        { return _next; }
-  void set_next(CodeEmitInfo* next) { _next = next; }
-
-  int id() const      { return _id; }
-  void set_id(int id) { _id = id; }
-
   bool     is_method_handle_invoke() const { return _is_method_handle_invoke;     }
   void set_is_method_handle_invoke(bool x) {        _is_method_handle_invoke = x; }
 };

src/share/vm/c1/c1_Instruction.cpp

@@ -29,13 +29,6 @@
 // Implementation of Instruction
 
 
-#ifdef ASSERT
-void Instruction::create_hi_word() {
-  assert(type()->is_double_word() && _hi_word == NULL, "only double word has high word");
-  _hi_word = new HiWord(this);
-}
-#endif
-
 Instruction::Condition Instruction::mirror(Condition cond) {
   switch (cond) {
     case eql: return eql;
@@ -63,6 +56,15 @@ Instruction::Condition Instruction::negate(Condition cond) {
   return eql;
 }
 
+void Instruction::update_exception_state(ValueStack* state) {
+  if (state != NULL && (state->kind() == ValueStack::EmptyExceptionState || state->kind() == ValueStack::ExceptionState)) {
+    assert(state->kind() == ValueStack::EmptyExceptionState || Compilation::current()->env()->jvmti_can_access_local_variables(), "unexpected state kind");
+    _exception_state = state;
+  } else {
+    _exception_state = NULL;
+  }
+}
+
 
 Instruction* Instruction::prev(BlockBegin* block) {
   Instruction* p = NULL;
@@ -75,7 +77,24 @@ Instruction* Instruction::prev(BlockBegin* block) {
 }
 
 
+void Instruction::state_values_do(ValueVisitor* f) {
+  if (state_before() != NULL) {
+    state_before()->values_do(f);
+  }
+  if (exception_state() != NULL){
+    exception_state()->values_do(f);
+  }
+}
+
+
 #ifndef PRODUCT
+void Instruction::check_state(ValueStack* state) {
+  if (state != NULL) {
+    state->verify();
+  }
+}
+
+
 void Instruction::print() {
   InstructionPrinter ip;
   print(ip);
@@ -190,35 +209,6 @@ ciType* CheckCast::exact_type() const {
   return NULL;
 }
 
-
-void ArithmeticOp::other_values_do(ValueVisitor* f) {
-  if (lock_stack() != NULL) lock_stack()->values_do(f);
-}
-
-void NullCheck::other_values_do(ValueVisitor* f) {
-  lock_stack()->values_do(f);
-}
-
-void AccessArray::other_values_do(ValueVisitor* f) {
-  if (lock_stack() != NULL) lock_stack()->values_do(f);
-}
-
-
-// Implementation of AccessField
-
-void AccessField::other_values_do(ValueVisitor* f) {
-  if (state_before() != NULL) state_before()->values_do(f);
-  if (lock_stack() != NULL) lock_stack()->values_do(f);
-}
-
-
-// Implementation of StoreIndexed
-
-IRScope* StoreIndexed::scope() const {
-  return lock_stack()->scope();
-}
-
-
 // Implementation of ArithmeticOp
 
 bool ArithmeticOp::is_commutative() const {
@@ -266,13 +256,6 @@ bool LogicOp::is_commutative() const {
 }
 
 
-// Implementation of CompareOp
-
-void CompareOp::other_values_do(ValueVisitor* f) {
-  if (state_before() != NULL) state_before()->values_do(f);
-}
-
-
 // Implementation of IfOp
 
 bool IfOp::is_commutative() const {
@@ -301,6 +284,7 @@ IRScope* StateSplit::scope() const {
 
 
 void StateSplit::state_values_do(ValueVisitor* f) {
+  Instruction::state_values_do(f);
   if (state() != NULL) state()->values_do(f);
 }
 
@@ -316,30 +300,17 @@ void BlockBegin::state_values_do(ValueVisitor* f) {
 }
 
 
-void MonitorEnter::state_values_do(ValueVisitor* f) {
-  StateSplit::state_values_do(f);
-  _lock_stack_before->values_do(f);
-}
-
-
-void Intrinsic::state_values_do(ValueVisitor* f) {
-  StateSplit::state_values_do(f);
-  if (lock_stack() != NULL) lock_stack()->values_do(f);
-}
-
-
 // Implementation of Invoke
 
 
 Invoke::Invoke(Bytecodes::Code code, ValueType* result_type, Value recv, Values* args,
                int vtable_index, ciMethod* target, ValueStack* state_before)
-  : StateSplit(result_type)
+  : StateSplit(result_type, state_before)
   , _code(code)
   , _recv(recv)
   , _args(args)
   , _vtable_index(vtable_index)
   , _target(target)
-  , _state_before(state_before)
 {
   set_flag(TargetIsLoadedFlag,   target->is_loaded());
   set_flag(TargetIsFinalFlag,    target_is_loaded() && target->is_final_method());
@@ -376,7 +347,7 @@ void Invoke::state_values_do(ValueVisitor* f) {
 
 // Implementation of Contant
 intx Constant::hash() const {
-  if (_state == NULL) {
+  if (state_before() == NULL) {
     switch (type()->tag()) {
     case intTag:
       return HASH2(name(), type()->as_IntConstant()->value());
@@ -499,25 +470,6 @@ BlockBegin* Constant::compare(Instruction::Condition cond, Value right,
 }
 
 
-void Constant::other_values_do(ValueVisitor* f) {
-  if (state() != NULL) state()->values_do(f);
-}
-
-
-// Implementation of NewArray
-
-void NewArray::other_values_do(ValueVisitor* f) {
-  if (state_before() != NULL) state_before()->values_do(f);
-}
-
-
-// Implementation of TypeCheck
-
-void TypeCheck::other_values_do(ValueVisitor* f) {
-  if (state_before() != NULL) state_before()->values_do(f);
-}
-
-
 // Implementation of BlockBegin
 
 void BlockBegin::set_end(BlockEnd* end) {
@@ -604,23 +556,14 @@ void BlockBegin::substitute_sux(BlockBegin* old_sux, BlockBegin* new_sux) {
 // of the inserted block, without recomputing the values of the other blocks
 // in the CFG. Therefore the value of "depth_first_number" in BlockBegin becomes meaningless.
 BlockBegin* BlockBegin::insert_block_between(BlockBegin* sux) {
-  // Try to make the bci close to a block with a single pred or sux,
-  // since this make the block layout algorithm work better.
-  int bci = -1;
-  if (sux->number_of_preds() == 1) {
-    bci = sux->bci();
-  } else {
-    bci = end()->bci();
-  }
-
-  BlockBegin* new_sux = new BlockBegin(bci);
+  BlockBegin* new_sux = new BlockBegin(-99);
 
   // mark this block (special treatment when block order is computed)
   new_sux->set(critical_edge_split_flag);
 
   // This goto is not a safepoint.
   Goto* e = new Goto(sux, false);
-  new_sux->set_next(e, bci);
+  new_sux->set_next(e, end()->state()->bci());
   new_sux->set_end(e);
   // setup states
   ValueStack* s = end()->state();
@@ -763,7 +706,7 @@ bool BlockBegin::try_merge(ValueStack* new_state) {
     }
 
     // copy state because it is altered
-    new_state = new_state->copy();
+    new_state = new_state->copy(ValueStack::BlockBeginState, bci());
 
     // Use method liveness to invalidate dead locals
     MethodLivenessResult liveness = new_state->scope()->method()->liveness_at_bci(bci());
@@ -800,19 +743,9 @@ bool BlockBegin::try_merge(ValueStack* new_state) {
     // initialize state of block
     set_state(new_state);
 
-  } else if (existing_state->is_same_across_scopes(new_state)) {
+  } else if (existing_state->is_same(new_state)) {
     TRACE_PHI(tty->print_cr("exisiting state found"));
 
-    // Inlining may cause the local state not to match up, so walk up
-    // the new state until we get to the same scope as the
-    // existing and then start processing from there.
-    while (existing_state->scope() != new_state->scope()) {
-      new_state = new_state->caller_state();
-      assert(new_state != NULL, "could not match up scopes");
-
-      assert(false, "check if this is necessary");
-    }
-
     assert(existing_state->scope() == new_state->scope(), "not matching");
     assert(existing_state->locals_size() == new_state->locals_size(), "not matching");
     assert(existing_state->stack_size() == new_state->stack_size(), "not matching");
@@ -969,11 +902,6 @@ void BlockEnd::substitute_sux(BlockBegin* old_sux, BlockBegin* new_sux) {
 }
 
 
-void BlockEnd::other_values_do(ValueVisitor* f) {
-  if (state_before() != NULL) state_before()->values_do(f);
-}
-
-
 // Implementation of Phi
 
 // Normal phi functions take their operands from the last instruction of the
@@ -1006,11 +934,6 @@ int Phi::operand_count() const {
 }
 
 
-// Implementation of Throw
-
-void Throw::state_values_do(ValueVisitor* f) {
-  BlockEnd::state_values_do(f);
-}
 
 void ProfileInvoke::state_values_do(ValueVisitor* f) {
   if (state() != NULL) state()->values_do(f);

src/share/vm/c1/c1_InstructionPrinter.cpp

@@ -316,7 +316,7 @@ void InstructionPrinter::print_head() {
 void InstructionPrinter::print_line(Instruction* instr) {
   // print instruction data on one line
   if (instr->is_pinned()) output()->put('.');
-  fill_to(bci_pos  ); output()->print("%d", instr->bci());
+  fill_to(bci_pos  ); output()->print("%d", instr->printable_bci());
   fill_to(use_pos  ); output()->print("%d", instr->use_count());
   fill_to(temp_pos ); print_temp(instr);
   fill_to(instr_pos); print_instr(instr);
@@ -569,7 +569,7 @@ void InstructionPrinter::do_BlockBegin(BlockBegin* x) {
   if (printed_flag) output()->print(") ");
 
   // print block bci range
-  output()->print("[%d, %d]", x->bci(), (end == NULL ? -1 : end->bci()));
+  output()->print("[%d, %d]", x->bci(), (end == NULL ? -1 : end->printable_bci()));
 
   // print block successors
   if (end != NULL && end->number_of_sux() > 0) {

src/share/vm/c1/c1_LIR.cpp

@@ -1520,7 +1520,7 @@ static void print_block(BlockBegin* x) {
   if (x->is_set(BlockBegin::linear_scan_loop_end_flag))    tty->print("le ");
 
   // print block bci range
-  tty->print("[%d, %d] ", x->bci(), (end == NULL ? -1 : end->bci()));
+  tty->print("[%d, %d] ", x->bci(), (end == NULL ? -1 : end->printable_bci()));
 
   // print predecessors and successors
   if (x->number_of_preds() > 0) {
@@ -1576,7 +1576,7 @@ void LIR_Op::print_on(outputStream* out) const {
   }
   out->print(name()); out->print(" ");
   print_instr(out);
-  if (info() != NULL) out->print(" [bci:%d]", info()->bci());
+  if (info() != NULL) out->print(" [bci:%d]", info()->stack()->bci());
 #ifdef ASSERT
   if (Verbose && _file != NULL) {
     out->print(" (%s:%d)", _file, _line);
@@ -1781,7 +1781,7 @@ void LIR_OpBranch::print_instr(outputStream* out) const {
     out->print("[");
     stub()->print_name(out);
     out->print(": 0x%x]", stub());
-    if (stub()->info() != NULL) out->print(" [bci:%d]", stub()->info()->bci());
+    if (stub()->info() != NULL) out->print(" [bci:%d]", stub()->info()->stack()->bci());
   } else {
     out->print("[label:0x%x] ", label());
   }
@@ -1896,7 +1896,7 @@ void LIR_OpTypeCheck::print_instr(outputStream* out) const {
   tmp2()->print(out);                    out->print(" ");
   tmp3()->print(out);                    out->print(" ");
   result_opr()->print(out);              out->print(" ");
-  if (info_for_exception() != NULL) out->print(" [bci:%d]", info_for_exception()->bci());
+  if (info_for_exception() != NULL) out->print(" [bci:%d]", info_for_exception()->stack()->bci());
 }
 
 

src/share/vm/c1/c1_LIRAssembler.cpp

@@ -35,7 +35,7 @@ void LIR_Assembler::patching_epilog(PatchingStub* patch, LIR_PatchCode patch_cod
   append_patching_stub(patch);
 
 #ifdef ASSERT
-  Bytecodes::Code code = info->scope()->method()->java_code_at_bci(info->bci());
+  Bytecodes::Code code = info->scope()->method()->java_code_at_bci(info->stack()->bci());
   if (patch->id() == PatchingStub::access_field_id) {
     switch (code) {
       case Bytecodes::_putstatic:
@@ -221,7 +221,7 @@ void LIR_Assembler::emit_block(BlockBegin* block) {
 #ifndef PRODUCT
   if (CommentedAssembly) {
     stringStream st;
-    st.print_cr(" block B%d [%d, %d]", block->block_id(), block->bci(), block->end()->bci());
+    st.print_cr(" block B%d [%d, %d]", block->block_id(), block->bci(), block->end()->printable_bci());
     _masm->block_comment(st.as_string());
   }
 #endif
@@ -312,7 +312,7 @@ void LIR_Assembler::add_call_info(int pc_offset, CodeEmitInfo* cinfo) {
 static ValueStack* debug_info(Instruction* ins) {
   StateSplit* ss = ins->as_StateSplit();
   if (ss != NULL) return ss->state();
-  return ins->lock_stack();
+  return ins->state_before();
 }
 
 void LIR_Assembler::process_debug_info(LIR_Op* op) {
@@ -327,8 +327,7 @@ void LIR_Assembler::process_debug_info(LIR_Op* op) {
   if (vstack == NULL)  return;
   if (_pending_non_safepoint != NULL) {
     // Got some old debug info.  Get rid of it.
-    if (_pending_non_safepoint->bci() == src->bci() &&
-        debug_info(_pending_non_safepoint) == vstack) {
+    if (debug_info(_pending_non_safepoint) == vstack) {
       _pending_non_safepoint_offset = pc_offset;
       return;
     }
@@ -358,7 +357,7 @@ static ValueStack* nth_oldest(ValueStack* s, int n, int& bci_result) {
     ValueStack* tc = t->caller_state();
     if (tc == NULL)  return s;
     t = tc;
-    bci_result = s->scope()->caller_bci();
+    bci_result = tc->bci();
     s = s->caller_state();
   }
 }
@@ -366,7 +365,7 @@ static ValueStack* nth_oldest(ValueStack* s, int n, int& bci_result) {
 void LIR_Assembler::record_non_safepoint_debug_info() {
   int         pc_offset = _pending_non_safepoint_offset;
   ValueStack* vstack    = debug_info(_pending_non_safepoint);
-  int         bci       = _pending_non_safepoint->bci();
+  int         bci       = vstack->bci();
 
   DebugInformationRecorder* debug_info = compilation()->debug_info_recorder();
   assert(debug_info->recording_non_safepoints(), "sanity");
@@ -380,7 +379,7 @@ void LIR_Assembler::record_non_safepoint_debug_info() {
     if (s == NULL)  break;
     IRScope* scope = s->scope();
     //Always pass false for reexecute since these ScopeDescs are never used for deopt
-    debug_info->describe_scope(pc_offset, scope->method(), s_bci, false/*reexecute*/);
+    debug_info->describe_scope(pc_offset, scope->method(), s->bci(), false/*reexecute*/);
   }
 
   debug_info->end_non_safepoint(pc_offset);

src/share/vm/c1/c1_LIRGenerator.cpp

@@ -386,18 +386,26 @@ void LIRGenerator::walk(Value instr) {
 
 
 CodeEmitInfo* LIRGenerator::state_for(Instruction* x, ValueStack* state, bool ignore_xhandler) {
-  int index;
-  Value value;
-  for_each_stack_value(state, index, value) {
-    assert(value->subst() == value, "missed substition");
-    if (!value->is_pinned() && value->as_Constant() == NULL && value->as_Local() == NULL) {
-      walk(value);
-      assert(value->operand()->is_valid(), "must be evaluated now");
-    }
-  }
+  assert(state != NULL, "state must be defined");
+
   ValueStack* s = state;
-  int bci = x->bci();
   for_each_state(s) {
+    if (s->kind() == ValueStack::EmptyExceptionState) {
+      assert(s->stack_size() == 0 && s->locals_size() == 0 && (s->locks_size() == 0 || s->locks_size() == 1), "state must be empty");
+      continue;
+    }
+
+    int index;
+    Value value;
+    for_each_stack_value(s, index, value) {
+      assert(value->subst() == value, "missed substitution");
+      if (!value->is_pinned() && value->as_Constant() == NULL && value->as_Local() == NULL) {
+        walk(value);
+        assert(value->operand()->is_valid(), "must be evaluated now");
+      }
+    }
+
+    int bci = s->bci();
     IRScope* scope = s->scope();
     ciMethod* method = scope->method();
 
@@ -428,15 +436,14 @@ CodeEmitInfo* LIRGenerator::state_for(Instruction* x, ValueStack* state, bool ig
         }
       }
     }
-    bci = scope->caller_bci();
   }
 
-  return new CodeEmitInfo(x->bci(), state, ignore_xhandler ? NULL : x->exception_handlers());
+  return new CodeEmitInfo(state, ignore_xhandler ? NULL : x->exception_handlers());
 }
 
 
 CodeEmitInfo* LIRGenerator::state_for(Instruction* x) {
-  return state_for(x, x->lock_stack());
+  return state_for(x, x->exception_state());
 }
 
 
@@ -900,18 +907,14 @@ void LIRGenerator::move_to_phi(ValueStack* cur_state) {
       Value sux_value;
       int index;
 
+      assert(cur_state->scope() == sux_state->scope(), "not matching");
+      assert(cur_state->locals_size() == sux_state->locals_size(), "not matching");
+      assert(cur_state->stack_size() == sux_state->stack_size(), "not matching");
+
       for_each_stack_value(sux_state, index, sux_value) {
         move_to_phi(&resolver, cur_state->stack_at(index), sux_value);
       }
 
-      // Inlining may cause the local state not to match up, so walk up
-      // the caller state until we get to the same scope as the
-      // successor and then start processing from there.
-      while (cur_state->scope() != sux_state->scope()) {
-        cur_state = cur_state->caller_state();
-        assert(cur_state != NULL, "scopes don't match up");
-      }
-
       for_each_local_value(sux_state, index, sux_value) {
         move_to_phi(&resolver, cur_state->local_at(index), sux_value);
       }
@@ -1023,10 +1026,10 @@ void LIRGenerator::do_Phi(Phi* x) {
 
 // Code for a constant is generated lazily unless the constant is frequently used and can't be inlined.
 void LIRGenerator::do_Constant(Constant* x) {
-  if (x->state() != NULL) {
+  if (x->state_before() != NULL) {
     // Any constant with a ValueStack requires patching so emit the patch here
     LIR_Opr reg = rlock_result(x);
-    CodeEmitInfo* info = state_for(x, x->state());
+    CodeEmitInfo* info = state_for(x, x->state_before());
     __ oop2reg_patch(NULL, reg, info);
   } else if (x->use_count() > 1 && !can_inline_as_constant(x)) {
     if (!x->is_pinned()) {
@@ -1102,7 +1105,7 @@ void LIRGenerator::do_getClass(Intrinsic* x) {
   // need to perform the null check on the rcvr
   CodeEmitInfo* info = NULL;
   if (x->needs_null_check()) {
-    info = state_for(x, x->state()->copy_locks());
+    info = state_for(x);
   }
   __ move(new LIR_Address(rcvr.result(), oopDesc::klass_offset_in_bytes(), T_OBJECT), result, info);
   __ move(new LIR_Address(result, Klass::java_mirror_offset_in_bytes() +
@@ -1481,7 +1484,7 @@ void LIRGenerator::do_StoreField(StoreField* x) {
   } else if (x->needs_null_check()) {
     NullCheck* nc = x->explicit_null_check();
     if (nc == NULL) {
-      info = state_for(x, x->lock_stack());
+      info = state_for(x);
     } else {
       info = state_for(nc);
     }
@@ -1509,10 +1512,12 @@ void LIRGenerator::do_StoreField(StoreField* x) {
 
   set_no_result(x);
 
+#ifndef PRODUCT
   if (PrintNotLoaded && needs_patching) {
     tty->print_cr("   ###class not loaded at store_%s bci %d",
-                  x->is_static() ?  "static" : "field", x->bci());
+                  x->is_static() ?  "static" : "field", x->printable_bci());
   }
+#endif
 
   if (x->needs_null_check() &&
       (needs_patching ||
@@ -1575,7 +1580,7 @@ void LIRGenerator::do_LoadField(LoadField* x) {
   } else if (x->needs_null_check()) {
     NullCheck* nc = x->explicit_null_check();
     if (nc == NULL) {
-      info = state_for(x, x->lock_stack());
+      info = state_for(x);
     } else {
       info = state_for(nc);
     }
@@ -1585,10 +1590,12 @@ void LIRGenerator::do_LoadField(LoadField* x) {
 
   object.load_item();
 
+#ifndef PRODUCT
   if (PrintNotLoaded && needs_patching) {
     tty->print_cr("   ###class not loaded at load_%s bci %d",
-                  x->is_static() ?  "static" : "field", x->bci());
+                  x->is_static() ?  "static" : "field", x->printable_bci());
   }
+#endif
 
   if (x->needs_null_check() &&
       (needs_patching ||
@@ -1781,7 +1788,7 @@ void LIRGenerator::do_Throw(Throw* x) {
   if (GenerateCompilerNullChecks &&
       (x->exception()->as_NewInstance() == NULL && x->exception()->as_ExceptionObject() == NULL)) {
     // if the exception object wasn't created using new then it might be null.
-    __ null_check(exception_opr, new CodeEmitInfo(info, true));
+    __ null_check(exception_opr, new CodeEmitInfo(info, x->state()->copy(ValueStack::ExceptionState, x->state()->bci())));
   }
 
   if (compilation()->env()->jvmti_can_post_on_exceptions()) {
@@ -2127,7 +2134,6 @@ void LIRGenerator::do_TableSwitch(TableSwitch* x) {
   int lo_key = x->lo_key();
   int hi_key = x->hi_key();
   int len = x->length();
-  CodeEmitInfo* info = state_for(x, x->state());
   LIR_Opr value = tag.result();
   if (UseTableRanges) {
     do_SwitchRanges(create_lookup_ranges(x), value, x->default_sux());
@@ -2186,7 +2192,7 @@ void LIRGenerator::do_Goto(Goto* x) {
 
     // increment backedge counter if needed
     CodeEmitInfo* info = state_for(x, state);
-    increment_backedge_counter(info, info->bci());
+    increment_backedge_counter(info, info->stack()->bci());
     CodeEmitInfo* safepoint_info = state_for(x, state);
     __ safepoint(safepoint_poll_register(), safepoint_info);
   }
@@ -2293,7 +2299,7 @@ void LIRGenerator::do_Base(Base* x) {
       LIR_Opr lock = new_register(T_INT);
       __ load_stack_address_monitor(0, lock);
 
-      CodeEmitInfo* info = new CodeEmitInfo(SynchronizationEntryBCI, scope()->start()->state(), NULL);
+      CodeEmitInfo* info = new CodeEmitInfo(scope()->start()->state()->copy(ValueStack::StateBefore, SynchronizationEntryBCI), NULL);
       CodeStub* slow_path = new MonitorEnterStub(obj, lock, info);
 
       // receiver is guaranteed non-NULL so don't need CodeEmitInfo
@@ -2303,7 +2309,7 @@ void LIRGenerator::do_Base(Base* x) {
 
   // increment invocation counters if needed
   if (!method()->is_accessor()) { // Accessors do not have MDOs, so no counting.
-    CodeEmitInfo* info = new CodeEmitInfo(InvocationEntryBci, scope()->start()->state(), NULL);
+    CodeEmitInfo* info = new CodeEmitInfo(scope()->start()->state(), NULL);
     increment_invocation_counter(info);
   }
 
@@ -2463,7 +2469,7 @@ void LIRGenerator::do_Invoke(Invoke* x) {
       break;
     case Bytecodes::_invokedynamic: {
       ciBytecodeStream bcs(x->scope()->method());
-      bcs.force_bci(x->bci());
+      bcs.force_bci(x->state()->bci());
       assert(bcs.cur_bc() == Bytecodes::_invokedynamic, "wrong stream");
       ciCPCache* cpcache = bcs.get_cpcache();
 

src/share/vm/c1/c1_LinearScan.cpp

@@ -2274,8 +2274,8 @@ void assert_equal(IRScopeDebugInfo* d1, IRScopeDebugInfo* d2) {
 }
 
 void check_stack_depth(CodeEmitInfo* info, int stack_end) {
-  if (info->bci() != SynchronizationEntryBCI && !info->scope()->method()->is_native()) {
-    Bytecodes::Code code = info->scope()->method()->java_code_at_bci(info->bci());
+  if (info->stack()->bci() != SynchronizationEntryBCI && !info->scope()->method()->is_native()) {
+    Bytecodes::Code code = info->scope()->method()->java_code_at_bci(info->stack()->bci());
     switch (code) {
       case Bytecodes::_ifnull    : // fall through
       case Bytecodes::_ifnonnull : // fall through
@@ -2379,7 +2379,7 @@ OopMap* LinearScan::compute_oop_map(IntervalWalker* iw, LIR_Op* op, CodeEmitInfo
 
   // add oops from lock stack
   assert(info->stack() != NULL, "CodeEmitInfo must always have a stack");
-  int locks_count = info->stack()->locks_size();
+  int locks_count = info->stack()->total_locks_size();
   for (int i = 0; i < locks_count; i++) {
     map->set_oop(frame_map()->monitor_object_regname(i));
   }
@@ -2762,19 +2762,13 @@ int LinearScan::append_scope_value(int op_id, Value value, GrowableArray<ScopeVa
 }
 
 
-IRScopeDebugInfo* LinearScan::compute_debug_info_for_scope(int op_id, IRScope* cur_scope, ValueStack* cur_state, ValueStack* innermost_state, int cur_bci, int stack_end, int locks_end) {
+IRScopeDebugInfo* LinearScan::compute_debug_info_for_scope(int op_id, IRScope* cur_scope, ValueStack* cur_state, ValueStack* innermost_state) {
   IRScopeDebugInfo* caller_debug_info = NULL;
-  int stack_begin, locks_begin;
 
-  ValueStack* caller_state = cur_scope->caller_state();
+  ValueStack* caller_state = cur_state->caller_state();
   if (caller_state != NULL) {
     // process recursively to compute outermost scope first
-    stack_begin = caller_state->stack_size();
-    locks_begin = caller_state->locks_size();
-    caller_debug_info = compute_debug_info_for_scope(op_id, cur_scope->caller(), caller_state, innermost_state, cur_scope->caller_bci(), stack_begin, locks_begin);
-  } else {
-    stack_begin = 0;
-    locks_begin = 0;
+    caller_debug_info = compute_debug_info_for_scope(op_id, cur_scope->caller(), caller_state, innermost_state);
   }
 
   // initialize these to null.
@@ -2785,7 +2779,7 @@ IRScopeDebugInfo* LinearScan::compute_debug_info_for_scope(int op_id, IRScope* c
   GrowableArray<MonitorValue*>* monitors    = NULL;
 
   // describe local variable values
-  int nof_locals = cur_scope->method()->max_locals();
+  int nof_locals = cur_state->locals_size();
   if (nof_locals > 0) {
     locals = new GrowableArray<ScopeValue*>(nof_locals);
 
@@ -2800,45 +2794,41 @@ IRScopeDebugInfo* LinearScan::compute_debug_info_for_scope(int op_id, IRScope* c
     }
     assert(locals->length() == cur_scope->method()->max_locals(), "wrong number of locals");
     assert(locals->length() == cur_state->locals_size(), "wrong number of locals");
+  } else if (cur_scope->method()->max_locals() > 0) {
+    assert(cur_state->kind() == ValueStack::EmptyExceptionState, "should be");
+    nof_locals = cur_scope->method()->max_locals();
+    locals = new GrowableArray<ScopeValue*>(nof_locals);
+    for(int i = 0; i < nof_locals; i++) {
+      locals->append(&_illegal_value);
+    }
   }
 
-
   // describe expression stack
-  //
-  // When we inline methods containing exception handlers, the
-  // "lock_stacks" are changed to preserve expression stack values
-  // in caller scopes when exception handlers are present. This
-  // can cause callee stacks to be smaller than caller stacks.
-  if (stack_end > innermost_state->stack_size()) {
-    stack_end = innermost_state->stack_size();
-  }
-
-
-
-  int nof_stack = stack_end - stack_begin;
+  int nof_stack = cur_state->stack_size();
   if (nof_stack > 0) {
     expressions = new GrowableArray<ScopeValue*>(nof_stack);
 
-    int pos = stack_begin;
-    while (pos < stack_end) {
-      Value expression = innermost_state->stack_at_inc(pos);
+    int pos = 0;
+    while (pos < nof_stack) {
+      Value expression = cur_state->stack_at_inc(pos);
       append_scope_value(op_id, expression, expressions);
 
-      assert(expressions->length() + stack_begin == pos, "must match");
+      assert(expressions->length() == pos, "must match");
     }
+    assert(expressions->length() == cur_state->stack_size(), "wrong number of stack entries");
   }
 
   // describe monitors
-  assert(locks_begin <= locks_end, "error in scope iteration");
-  int nof_locks = locks_end - locks_begin;
+  int nof_locks = cur_state->locks_size();
   if (nof_locks > 0) {
+    int lock_offset = cur_state->caller_state() != NULL ? cur_state->caller_state()->total_locks_size() : 0;
     monitors = new GrowableArray<MonitorValue*>(nof_locks);
-    for (int i = locks_begin; i < locks_end; i++) {
-      monitors->append(location_for_monitor_index(i));
+    for (int i = 0; i < nof_locks; i++) {
+      monitors->append(location_for_monitor_index(lock_offset + i));
     }
   }
 
-  return new IRScopeDebugInfo(cur_scope, cur_bci, locals, expressions, monitors, caller_debug_info);
+  return new IRScopeDebugInfo(cur_scope, cur_state->bci(), locals, expressions, monitors, caller_debug_info);
 }
 
 
@@ -2850,17 +2840,14 @@ void LinearScan::compute_debug_info(CodeEmitInfo* info, int op_id) {
 
   assert(innermost_scope != NULL && innermost_state != NULL, "why is it missing?");
 
-  int stack_end = innermost_state->stack_size();
-  int locks_end = innermost_state->locks_size();
-
-  DEBUG_ONLY(check_stack_depth(info, stack_end));
+  DEBUG_ONLY(check_stack_depth(info, innermost_state->stack_size()));
 
   if (info->_scope_debug_info == NULL) {
     // compute debug information
-    info->_scope_debug_info = compute_debug_info_for_scope(op_id, innermost_scope, innermost_state, innermost_state, info->bci(), stack_end, locks_end);
+    info->_scope_debug_info = compute_debug_info_for_scope(op_id, innermost_scope, innermost_state, innermost_state);
   } else {
     // debug information already set. Check that it is correct from the current point of view
-    DEBUG_ONLY(assert_equal(info->_scope_debug_info, compute_debug_info_for_scope(op_id, innermost_scope, innermost_state, innermost_state, info->bci(), stack_end, locks_end)));
+    DEBUG_ONLY(assert_equal(info->_scope_debug_info, compute_debug_info_for_scope(op_id, innermost_scope, innermost_state, innermost_state)));
   }
 }
 

src/share/vm/c1/c1_LinearScan.hpp

@@ -346,7 +346,7 @@ class LinearScan : public CompilationResourceObj {
   int append_scope_value_for_operand(LIR_Opr opr, GrowableArray<ScopeValue*>* scope_values);
   int append_scope_value(int op_id, Value value, GrowableArray<ScopeValue*>* scope_values);
 
-  IRScopeDebugInfo* compute_debug_info_for_scope(int op_id, IRScope* cur_scope, ValueStack* cur_state, ValueStack* innermost_state, int cur_bci, int stack_end, int locks_end);
+  IRScopeDebugInfo* compute_debug_info_for_scope(int op_id, IRScope* cur_scope, ValueStack* cur_state, ValueStack* innermost_state);
   void compute_debug_info(CodeEmitInfo* info, int op_id);
 
   void assign_reg_num(LIR_OpList* instructions, IntervalWalker* iw);

src/share/vm/c1/c1_Optimizer.cpp

@@ -140,25 +140,27 @@ class CE_Eliminator: public BlockClosure {
     //    with an IfOp followed by a Goto
     // cut if_ away and get node before
     Instruction* cur_end = if_->prev(block);
-    int bci = if_->bci();
 
     // append constants of true- and false-block if necessary
     // clone constants because original block must not be destroyed
     assert((t_value != f_const && f_value != t_const) || t_const == f_const, "mismatch");
     if (t_value == t_const) {
       t_value = new Constant(t_const->type());
-      cur_end = cur_end->set_next(t_value, bci);
+      NOT_PRODUCT(t_value->set_printable_bci(if_->printable_bci()));
+      cur_end = cur_end->set_next(t_value);
     }
     if (f_value == f_const) {
       f_value = new Constant(f_const->type());
-      cur_end = cur_end->set_next(f_value, bci);
+      NOT_PRODUCT(f_value->set_printable_bci(if_->printable_bci()));
+      cur_end = cur_end->set_next(f_value);
     }
 
     // it is very unlikely that the condition can be statically decided
     // (this was checked previously by the Canonicalizer), so always
     // append IfOp
     Value result = new IfOp(if_->x(), if_->cond(), if_->y(), t_value, f_value);
-    cur_end = cur_end->set_next(result, bci);
+    NOT_PRODUCT(result->set_printable_bci(if_->printable_bci()));
+    cur_end = cur_end->set_next(result);
 
     // append Goto to successor
     ValueStack* state_before = if_->is_safepoint() ? if_->state_before() : NULL;
@@ -167,16 +169,15 @@ class CE_Eliminator: public BlockClosure {
     // prepare state for Goto
     ValueStack* goto_state = if_->state();
     while (sux_state->scope() != goto_state->scope()) {
-      goto_state = goto_state->pop_scope();
+      goto_state = goto_state->caller_state();
       assert(goto_state != NULL, "states do not match up");
     }
-    goto_state = goto_state->copy();
+    goto_state = goto_state->copy(ValueStack::StateAfter, goto_state->bci());
     goto_state->push(result->type(), result);
-    assert(goto_state->is_same_across_scopes(sux_state), "states must match now");
+    assert(goto_state->is_same(sux_state), "states must match now");
     goto_->set_state(goto_state);
 
-    // Steal the bci for the goto from the sux
-    cur_end = cur_end->set_next(goto_, sux->bci());
+    cur_end = cur_end->set_next(goto_, goto_state->bci());
 
     // Adjust control flow graph
     BlockBegin::disconnect_edge(block, t_block);
@@ -251,10 +252,8 @@ class BlockMerger: public BlockClosure {
         // no phi functions must be present at beginning of sux
         ValueStack* sux_state = sux->state();
         ValueStack* end_state = end->state();
-        while (end_state->scope() != sux_state->scope()) {
-          // match up inlining level
-          end_state = end_state->pop_scope();
-        }
+
+        assert(end_state->scope() == sux_state->scope(), "scopes must match");
         assert(end_state->stack_size() == sux_state->stack_size(), "stack not equal");
         assert(end_state->locals_size() == sux_state->locals_size(), "locals not equal");
 
@@ -273,7 +272,7 @@ class BlockMerger: public BlockClosure {
         Instruction* prev = end->prev(block);
         Instruction* next = sux->next();
         assert(prev->as_BlockEnd() == NULL, "must not be a BlockEnd");
-        prev->set_next(next, next->bci());
+        prev->set_next(next);
         sux->disconnect_from_graph();
         block->set_end(sux->end());
         // add exception handlers of deleted block, if any
@@ -337,7 +336,8 @@ class BlockMerger: public BlockClosure {
                   newif->set_state(if_->state()->copy());
 
                   assert(prev->next() == if_, "must be guaranteed by above search");
-                  prev->set_next(newif, if_->bci());
+                  NOT_PRODUCT(newif->set_printable_bci(if_->printable_bci()));
+                  prev->set_next(newif);
                   block->set_end(newif);
 
                   _merge_count++;
@@ -705,7 +705,7 @@ void NullCheckEliminator::iterate_one(BlockBegin* block) {
     // visiting instructions which are references in other blocks or
     // visiting instructions more than once.
     mark_visitable(instr);
-    if (instr->is_root() || instr->can_trap() || (instr->as_NullCheck() != NULL)) {
+    if (instr->is_pinned() || instr->can_trap() || (instr->as_NullCheck() != NULL)) {
       mark_visited(instr);
       instr->input_values_do(this);
       instr->visit(&_visitor);

src/share/vm/c1/c1_ValueStack.cpp

@@ -28,55 +28,60 @@
 
 // Implementation of ValueStack
 
-ValueStack::ValueStack(IRScope* scope, int locals_size, int max_stack_size)
+ValueStack::ValueStack(IRScope* scope, ValueStack* caller_state)
 : _scope(scope)
-, _locals(locals_size, NULL)
-, _stack(max_stack_size)
-, _lock_stack(false)
-, _locks(1)
+, _caller_state(caller_state)
+, _bci(-99)
+, _kind(Parsing)
+, _locals(scope->method()->max_locals(), NULL)
+, _stack(scope->method()->max_stack())
+, _locks()
 {
-  assert(scope != NULL, "scope must exist");
-}
-
-ValueStack* ValueStack::copy() {
-  ValueStack* s = new ValueStack(scope(), locals_size(), max_stack_size());
-  s->_stack.appendAll(&_stack);
-  s->_locks.appendAll(&_locks);
-  s->replace_locals(this);
-  return s;
+  verify();
 }
 
 
-ValueStack* ValueStack::copy_locks() {
-  int sz = scope()->lock_stack_size();
-  if (stack_size() == 0) {
-    sz = 0;
+ValueStack::ValueStack(ValueStack* copy_from, Kind kind, int bci)
+  : _scope(copy_from->scope())
+  , _caller_state(copy_from->caller_state())
+  , _bci(bci)
+  , _kind(kind)
+  , _locals()
+  , _stack()
+  , _locks(copy_from->locks_size())
+{
+  assert(kind != EmptyExceptionState || !Compilation::current()->env()->jvmti_can_access_local_variables(), "need locals");
+  if (kind != EmptyExceptionState) {
+    // only allocate space if we need to copy the locals-array
+    _locals = Values(copy_from->locals_size());
+    _locals.appendAll(&copy_from->_locals);
   }
-  ValueStack* s = new ValueStack(scope(), locals_size(), sz);
-  s->_lock_stack = true;
-  s->_locks.appendAll(&_locks);
-  s->replace_locals(this);
-  if (sz > 0) {
-    assert(sz <= stack_size(), "lock stack underflow");
-    for (int i = 0; i < sz; i++) {
-      s->_stack.append(_stack[i]);
+
+  if (kind != ExceptionState && kind != EmptyExceptionState) {
+    if (kind == Parsing) {
+      // stack will be modified, so reserve enough space to avoid resizing
+      _stack = Values(scope()->method()->max_stack());
+    } else {
+      // stack will not be modified, so do not waste space
+      _stack = Values(copy_from->stack_size());
     }
+    _stack.appendAll(&copy_from->_stack);
   }
-  return s;
+
+  _locks.appendAll(&copy_from->_locks);
+
+  verify();
 }
 
+
 bool ValueStack::is_same(ValueStack* s) {
-  assert(s != NULL, "state must exist");
-  assert(scope      () == s->scope      (), "scopes       must correspond");
-  assert(locals_size() == s->locals_size(), "locals sizes must correspond");
-  return is_same_across_scopes(s);
-}
+  if (scope() != s->scope()) return false;
+  if (caller_state() != s->caller_state()) return false;
 
+  if (locals_size() != s->locals_size()) return false;
+  if (stack_size() != s->stack_size()) return false;
+  if (locks_size() != s->locks_size()) return false;
 
-bool ValueStack::is_same_across_scopes(ValueStack* s) {
-  assert(s != NULL, "state must exist");
-  assert(stack_size () == s->stack_size (), "stack  sizes must correspond");
-  assert(locks_size () == s->locks_size (), "locks  sizes must correspond");
   // compare each stack element with the corresponding stack element of s
   int index;
   Value value;
@@ -89,12 +94,6 @@ bool ValueStack::is_same_across_scopes(ValueStack* s) {
   return true;
 }
 
-
-ValueStack* ValueStack::caller_state() const {
-  return scope()->caller_state();
-}
-
-
 void ValueStack::clear_locals() {
   for (int i = _locals.length() - 1; i >= 0; i--) {
     _locals.at_put(i, NULL);
@@ -102,13 +101,6 @@ void ValueStack::clear_locals() {
 }
 
 
-void ValueStack::replace_locals(ValueStack* with) {
-  assert(locals_size() == with->locals_size(), "number of locals must match");
-  for (int i = locals_size() - 1; i >= 0; i--) {
-    _locals.at_put(i, with->_locals.at(i));
-  }
-}
-
 void ValueStack::pin_stack_for_linear_scan() {
   for_each_state_value(this, v,
     if (v->as_Constant() == NULL && v->as_Local() == NULL) {
@@ -123,33 +115,25 @@ void ValueStack::apply(Values list, ValueVisitor* f) {
   for (int i = 0; i < list.length(); i++) {
     Value* va = list.adr_at(i);
     Value v0 = *va;
-    if (v0 != NULL) {
-      if (!v0->type()->is_illegal()) {
-        assert(v0->as_HiWord() == NULL, "should never see HiWord during traversal");
-        f->visit(va);
+    if (v0 != NULL && !v0->type()->is_illegal()) {
+      f->visit(va);
 #ifdef ASSERT
-        Value v1 = *va;
-        if (v0 != v1) {
-          assert(v1->type()->is_illegal() || v0->type()->tag() == v1->type()->tag(), "types must match");
-          if (v0->type()->is_double_word()) {
-            list.at_put(i + 1, v0->hi_word());
-          }
-        }
+      Value v1 = *va;
+      assert(v1->type()->is_illegal() || v0->type()->tag() == v1->type()->tag(), "types must match");
+      assert(!v1->type()->is_double_word() || list.at(i + 1) == NULL, "hi-word of doubleword value must be NULL");
 #endif
-        if (v0->type()->is_double_word()) i++;
-      }
+      if (v0->type()->is_double_word()) i++;
     }
   }
 }
 
 
 void ValueStack::values_do(ValueVisitor* f) {
-  apply(_stack, f);
-  apply(_locks, f);
-
   ValueStack* state = this;
   for_each_state(state) {
     apply(state->_locals, f);
+    apply(state->_stack, f);
+    apply(state->_locks, f);
   }
 }
 
@@ -164,52 +148,26 @@ Values* ValueStack::pop_arguments(int argument_size) {
 }
 
 
-int ValueStack::lock(IRScope* scope, Value obj) {
+int ValueStack::total_locks_size() const {
+  int num_locks = 0;
+  const ValueStack* state = this;
+  for_each_state(state) {
+    num_locks += state->locks_size();
+  }
+  return num_locks;
+}
+
+int ValueStack::lock(Value obj) {
   _locks.push(obj);
-  scope->set_min_number_of_locks(locks_size());
-  return locks_size() - 1;
+  int num_locks = total_locks_size();
+  scope()->set_min_number_of_locks(num_locks);
+  return num_locks - 1;
 }
 
 
 int ValueStack::unlock() {
   _locks.pop();
-  return locks_size();
-}
-
-
-ValueStack* ValueStack::push_scope(IRScope* scope) {
-  assert(scope->caller() == _scope, "scopes must have caller/callee relationship");
-  ValueStack* res = new ValueStack(scope,
-                                   scope->method()->max_locals(),
-                                   max_stack_size() + scope->method()->max_stack());
-  // Preserves stack and monitors.
-  res->_stack.appendAll(&_stack);
-  res->_locks.appendAll(&_locks);
-  assert(res->_stack.size() <= res->max_stack_size(), "stack overflow");
-  return res;
-}
-
-
-ValueStack* ValueStack::pop_scope() {
-  assert(_scope->caller() != NULL, "scope must have caller");
-  IRScope* scope = _scope->caller();
-  int max_stack = max_stack_size() - _scope->method()->max_stack();
-  assert(max_stack >= 0, "stack underflow");
-  ValueStack* res = new ValueStack(scope,
-                                   scope->method()->max_locals(),
-                                   max_stack);
-  // Preserves stack and monitors. Restores local and store state from caller scope.
-  res->_stack.appendAll(&_stack);
-  res->_locks.appendAll(&_locks);
-  ValueStack* caller = caller_state();
-  if (caller != NULL) {
-    for (int i = 0; i < caller->_locals.length(); i++) {
-      res->_locals.at_put(i, caller->_locals.at(i));
-    }
-    assert(res->_locals.length() == res->scope()->method()->max_locals(), "just checking");
-  }
-  assert(res->_stack.size() <= res->max_stack_size(), "stack overflow");
-  return res;
+  return total_locks_size();
 }
 
 
@@ -220,11 +178,7 @@ void ValueStack::setup_phi_for_stack(BlockBegin* b, int index) {
   Value phi = new Phi(t, b, -index - 1);
   _stack[index] = phi;
 
-#ifdef ASSERT
-  if (t->is_double_word()) {
-    _stack[index + 1] = phi->hi_word();
-  }
-#endif
+  assert(!t->is_double_word() || _stack.at(index + 1) == NULL, "hi-word of doubleword value must be NULL");
 }
 
 void ValueStack::setup_phi_for_local(BlockBegin* b, int index) {
@@ -236,7 +190,9 @@ void ValueStack::setup_phi_for_local(BlockBegin* b, int index) {
 }
 
 #ifndef PRODUCT
+
 void ValueStack::print() {
+  scope()->method()->print_name();
   if (stack_is_empty()) {
     tty->print_cr("empty stack");
   } else {
@@ -244,18 +200,20 @@ void ValueStack::print() {
     for (int i = 0; i < stack_size();) {
       Value t = stack_at_inc(i);
       tty->print("%2d  ", i);
+      tty->print("%c%d ", t->type()->tchar(), t->id());
       ip.print_instr(t);
       tty->cr();
     }
   }
   if (!no_active_locks()) {
     InstructionPrinter ip;
-    for (int i = 0; i < locks_size(); i--) {
+    for (int i = 0; i < locks_size(); i++) {
       Value t = lock_at(i);
       tty->print("lock %2d  ", i);
       if (t == NULL) {
         tty->print("this");
       } else {
+        tty->print("%c%d ", t->type()->tchar(), t->id());
         ip.print_instr(t);
       }
       tty->cr();
@@ -270,16 +228,55 @@ void ValueStack::print() {
         tty->print("null");
         i ++;
       } else {
+        tty->print("%c%d ", l->type()->tchar(), l->id());
         ip.print_instr(l);
         if (l->type()->is_illegal() || l->type()->is_single_word()) i ++; else i += 2;
       }
       tty->cr();
     }
   }
+
+  if (caller_state() != NULL) {
+    caller_state()->print();
+  }
 }
 
 
 void ValueStack::verify() {
-  Unimplemented();
+  assert(scope() != NULL, "scope must exist");
+  if (caller_state() != NULL) {
+    assert(caller_state()->scope() == scope()->caller(), "invalid caller scope");
+    caller_state()->verify();
+  }
+
+  if (kind() == Parsing) {
+    assert(bci() == -99, "bci not defined during parsing");
+  } else {
+    assert(bci() >= -1, "bci out of range");
+    assert(bci() < scope()->method()->code_size(), "bci out of range");
+    assert(bci() == SynchronizationEntryBCI || Bytecodes::is_defined(scope()->method()->java_code_at_bci(bci())), "make sure bci points at a real bytecode");
+    assert(scope()->method()->liveness_at_bci(bci()).is_valid(), "liveness at bci must be valid");
+  }
+
+  int i;
+  for (i = 0; i < stack_size(); i++) {
+    Value v = _stack.at(i);
+    if (v == NULL) {
+      assert(_stack.at(i - 1)->type()->is_double_word(), "only hi-words are NULL on stack");
+    } else if (v->type()->is_double_word()) {
+      assert(_stack.at(i + 1) == NULL, "hi-word must be NULL");
+    }
+  }
+
+  for (i = 0; i < locals_size(); i++) {
+    Value v = _locals.at(i);
+    if (v != NULL && v->type()->is_double_word()) {
+      assert(_locals.at(i + 1) == NULL, "hi-word must be NULL");
+    }
+  }
+
+  for_each_state_value(this, v,
+    assert(v != NULL, "just test if state-iteration succeeds");
+  );
 }
 #endif // PRODUCT

src/share/vm/c1/c1_ValueStack.hpp

@@ -23,9 +23,23 @@
  */
 
 class ValueStack: public CompilationResourceObj {
+ public:
+  enum Kind {
+    Parsing,             // During abstract interpretation in GraphBuilder
+    CallerState,         // Caller state when inlining
+    StateBefore,         // Before before execution of instruction
+    StateAfter,          // After execution of instruction
+    ExceptionState,      // Exception handling of instruction
+    EmptyExceptionState, // Exception handling of instructions not covered by an xhandler
+    BlockBeginState      // State of BlockBegin instruction with phi functions of this block
+  };
+
  private:
   IRScope* _scope;                               // the enclosing scope
-  bool     _lock_stack;                          // indicates that this ValueStack is for an exception site
+  ValueStack* _caller_state;
+  int      _bci;
+  Kind     _kind;
+
   Values   _locals;                              // the locals
   Values   _stack;                               // the expression stack
   Values   _locks;                               // the monitor stack (holding the locked values)
@@ -36,100 +50,79 @@ class ValueStack: public CompilationResourceObj {
   }
 
   Value check(ValueTag tag, Value t, Value h) {
-    assert(h->as_HiWord()->lo_word() == t, "incorrect stack pair");
+    assert(h == NULL, "hi-word of doubleword value must be NULL");
     return check(tag, t);
   }
 
   // helper routine
   static void apply(Values list, ValueVisitor* f);
 
+  // for simplified copying
+  ValueStack(ValueStack* copy_from, Kind kind, int bci);
+
  public:
   // creation
-  ValueStack(IRScope* scope, int locals_size, int max_stack_size);
-
-  // merging
-  ValueStack* copy();                            // returns a copy of this w/ cleared locals
-  ValueStack* copy_locks();                      // returns a copy of this w/ cleared locals and stack
-                                                 // Note that when inlining of methods with exception
-                                                 // handlers is enabled, this stack may have a
-                                                 // non-empty expression stack (size defined by
-                                                 // scope()->lock_stack_size())
+  ValueStack(IRScope* scope, ValueStack* caller_state);
+
+  ValueStack* copy()                             { return new ValueStack(this, _kind, _bci); }
+  ValueStack* copy(Kind new_kind, int new_bci)   { return new ValueStack(this, new_kind, new_bci); }
+  ValueStack* copy_for_parsing()                 { return new ValueStack(this, Parsing, -99); }
+
+  void set_caller_state(ValueStack* s)           { assert(kind() == EmptyExceptionState, "only EmptyExceptionStates can be modified"); _caller_state = s; }
+
   bool is_same(ValueStack* s);                   // returns true if this & s's types match (w/o checking locals)
-  bool is_same_across_scopes(ValueStack* s);     // same as is_same but returns true even if stacks are in different scopes (used for block merging w/inlining)
 
   // accessors
   IRScope* scope() const                         { return _scope; }
-  bool is_lock_stack() const                     { return _lock_stack; }
+  ValueStack* caller_state() const               { return _caller_state; }
+  int bci() const                                { return _bci; }
+  Kind kind() const                              { return _kind; }
+
   int locals_size() const                        { return _locals.length(); }
   int stack_size() const                         { return _stack.length(); }
   int locks_size() const                         { return _locks.length(); }
-  int max_stack_size() const                     { return _stack.capacity(); }
   bool stack_is_empty() const                    { return _stack.is_empty(); }
   bool no_active_locks() const                   { return _locks.is_empty(); }
-  ValueStack* caller_state() const;
+  int total_locks_size() const;
 
   // locals access
   void clear_locals();                           // sets all locals to NULL;
 
-  // Kill local i.  Also kill local i+1 if i was a long or double.
   void invalidate_local(int i) {
-    Value x = _locals.at(i);
-    if (x != NULL && x->type()->is_double_word()) {
-      assert(_locals.at(i + 1)->as_HiWord()->lo_word() == x, "locals inconsistent");
-      _locals.at_put(i + 1, NULL);
-    }
+    assert(_locals.at(i)->type()->is_single_word() ||
+           _locals.at(i + 1) == NULL, "hi-word of doubleword value must be NULL");
     _locals.at_put(i, NULL);
   }
 
-
-  Value load_local(int i) const {
+  Value local_at(int i) const {
     Value x = _locals.at(i);
-    if (x != NULL && x->type()->is_illegal()) return NULL;
-    assert(x == NULL || x->as_HiWord() == NULL, "index points to hi word");
-    assert(x == NULL || x->type()->is_illegal() || x->type()->is_single_word() || x == _locals.at(i+1)->as_HiWord()->lo_word(), "locals inconsistent");
+    assert(x == NULL || x->type()->is_single_word() ||
+           _locals.at(i + 1) == NULL, "hi-word of doubleword value must be NULL");
     return x;
   }
 
-  Value local_at(int i) const { return _locals.at(i); }
-
-  // Store x into local i.
   void store_local(int i, Value x) {
-    // Kill the old value
-    invalidate_local(i);
-    _locals.at_put(i, x);
-
-    // Writing a double word can kill other locals
-    if (x != NULL && x->type()->is_double_word()) {
-      // If x + i was the start of a double word local then kill i + 2.
-      Value x2 = _locals.at(i + 1);
-      if (x2 != NULL && x2->type()->is_double_word()) {
-        _locals.at_put(i + 2, NULL);
-      }
-
-      // If x is a double word local, also update i + 1.
-#ifdef ASSERT
-      _locals.at_put(i + 1, x->hi_word());
-#else
-      _locals.at_put(i + 1, NULL);
-#endif
-    }
-    // If x - 1 was the start of a double word local then kill i - 1.
+    // When overwriting local i, check if i - 1 was the start of a
+    // double word local and kill it.
     if (i > 0) {
       Value prev = _locals.at(i - 1);
       if (prev != NULL && prev->type()->is_double_word()) {
         _locals.at_put(i - 1, NULL);
       }
     }
-  }
 
-  void replace_locals(ValueStack* with);
+    _locals.at_put(i, x);
+    if (x->type()->is_double_word()) {
+      // hi-word of doubleword value is always NULL
+      _locals.at_put(i + 1, NULL);
+    }
+  }
 
   // stack access
   Value stack_at(int i) const {
     Value x = _stack.at(i);
-    assert(x->as_HiWord() == NULL, "index points to hi word");
     assert(x->type()->is_single_word() ||
-           x->subst() == _stack.at(i+1)->as_HiWord()->lo_word(), "stack inconsistent");
+           _stack.at(i + 1) == NULL, "hi-word of doubleword value must be NULL");
     return x;
   }
 
@@ -146,7 +139,6 @@ class ValueStack: public CompilationResourceObj {
   void values_do(ValueVisitor* f);
 
   // untyped manipulation (for dup_x1, etc.)
-  void clear_stack()                             { _stack.clear(); }
   void truncate_stack(int size)                  { _stack.trunc_to(size); }
   void raw_push(Value t)                         { _stack.push(t); }
   Value raw_pop()                                { return _stack.pop(); }
@@ -156,15 +148,8 @@ class ValueStack: public CompilationResourceObj {
   void fpush(Value t)                            { _stack.push(check(floatTag  , t)); }
   void apush(Value t)                            { _stack.push(check(objectTag , t)); }
   void rpush(Value t)                            { _stack.push(check(addressTag, t)); }
-#ifdef ASSERT
-  // in debug mode, use HiWord for 2-word values
-  void lpush(Value t)                            { _stack.push(check(longTag   , t)); _stack.push(new HiWord(t)); }
-  void dpush(Value t)                            { _stack.push(check(doubleTag , t)); _stack.push(new HiWord(t)); }
-#else
-  // in optimized mode, use NULL for 2-word values
   void lpush(Value t)                            { _stack.push(check(longTag   , t)); _stack.push(NULL); }
   void dpush(Value t)                            { _stack.push(check(doubleTag , t)); _stack.push(NULL); }
-#endif // ASSERT
 
   void push(ValueType* type, Value t) {
     switch (type->tag()) {
@@ -182,15 +167,8 @@ class ValueStack: public CompilationResourceObj {
   Value fpop()                                   { return check(floatTag  , _stack.pop()); }
   Value apop()                                   { return check(objectTag , _stack.pop()); }
   Value rpop()                                   { return check(addressTag, _stack.pop()); }
-#ifdef ASSERT
-  // in debug mode, check for HiWord consistency
   Value lpop()                                   { Value h = _stack.pop(); return check(longTag  , _stack.pop(), h); }
   Value dpop()                                   { Value h = _stack.pop(); return check(doubleTag, _stack.pop(), h); }
-#else
-  // in optimized mode, ignore HiWord since it is NULL
-  Value lpop()                                   { _stack.pop(); return check(longTag  , _stack.pop()); }
-  Value dpop()                                   { _stack.pop(); return check(doubleTag, _stack.pop()); }
-#endif // ASSERT
 
   Value pop(ValueType* type) {
     switch (type->tag()) {
@@ -208,16 +186,10 @@ class ValueStack: public CompilationResourceObj {
   Values* pop_arguments(int argument_size);
 
   // locks access
-  int lock  (IRScope* scope, Value obj);
+  int lock  (Value obj);
   int unlock();
   Value lock_at(int i) const                     { return _locks.at(i); }
 
-  // Inlining support
-  ValueStack* push_scope(IRScope* scope);         // "Push" new scope, returning new resulting stack
-                                                  // Preserves stack and locks, destroys locals
-  ValueStack* pop_scope();                        // "Pop" topmost scope, returning new resulting stack
-                                                  // Preserves stack and locks, destroys locals
-
   // SSA form IR support
   void setup_phi_for_stack(BlockBegin* b, int index);
   void setup_phi_for_local(BlockBegin* b, int index);
@@ -298,16 +270,18 @@ class ValueStack: public CompilationResourceObj {
 {                                                                                              \
   int cur_index;                                                                               \
   ValueStack* cur_state = v_state;                                                             \
-  Value v_value;                                                                                 \
-  {                                                                                            \
-    for_each_stack_value(cur_state, cur_index, v_value) {                                      \
-      v_code;                                                                                  \
-    }                                                                                          \
-  }                                                                                            \
+  Value v_value;                                                                               \
   for_each_state(cur_state) {                                                                  \
-    for_each_local_value(cur_state, cur_index, v_value) {                                      \
-      v_code;                                                                                  \
+    {                                                                                            \
+      for_each_local_value(cur_state, cur_index, v_value) {                                      \
+        v_code;                                                                                  \
+      }                                                                                          \
     }                                                                                          \
+    {                                                                                            \
+      for_each_stack_value(cur_state, cur_index, v_value) {                                      \
+        v_code;                                                                                  \
+      }                                                                                          \
+    }                                                                                            \
   }                                                                                            \
 }
 

src/share/vm/c1/c1_globals.hpp

@@ -216,9 +216,6 @@
   develop(bool, DeoptC1, true,                                              \
           "Use deoptimization in C1")                                       \
                                                                             \
-  develop(bool, DeoptOnAsyncException, true,                                \
-          "Deoptimize upon Thread.stop(); improves precision of IR")        \
-                                                                            \
   develop(bool, PrintBailouts, false,                                       \
           "Print bailout and its reason")                                   \
                                                                             \

src/share/vm/includeDB_compiler1

@@ -448,3 +448,7 @@ thread.cpp                              c1_Compiler.hpp
 top.hpp                                 c1_globals.hpp
 
 vmStructs.hpp                           c1_Runtime1.hpp
+
+c1_Canonicalizer.cpp                    c1_ValueStack.hpp
+
+c1_LIR.cpp                              c1_ValueStack.hpp