jdk8-mips64-public/hotspot: src/share/vm/ci/ciTypeFlow.hpp@4ce7240d622c (annotated)

src/share/vm/ci/ciTypeFlow.hpp@4ce7240d622c (annotated)

src/share/vm/ci/ciTypeFlow.hpp

Wed, 06 Jan 2010 14:22:39 -0800

author: never
date: Wed, 06 Jan 2010 14:22:39 -0800
changeset 1577: 4ce7240d622c
parent 815: eb28cf662f56
child 1907: c18cbe5936b8
permissions: -rw-r--r--

6914300: ciEnv should export all well known classes
Reviewed-by: kvn, twisti

 /*
  * Copyright 2000-2008 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  * CA 95054 USA or visit www.sun.com if you need additional information or
  * have any questions.
  *
  */
 class ciTypeFlow : public ResourceObj {
 private:
   ciEnv*    _env;
   ciMethod* _method;
   ciMethodBlocks* _methodBlocks;
   int       _osr_bci;
   // information cached from the method:
   int _max_locals;
   int _max_stack;
   int _code_size;
   bool      _has_irreducible_entry;
   const char* _failure_reason;
 public:
   class StateVector;
   class Loop;
   class Block;
   // Build a type flow analyzer
   // Do an OSR analysis if osr_bci >= 0.
   ciTypeFlow(ciEnv* env, ciMethod* method, int osr_bci = InvocationEntryBci);
   // Accessors
   ciMethod* method() const     { return _method; }
   ciEnv*    env()              { return _env; }
   Arena*    arena()            { return _env->arena(); }
   bool      is_osr_flow() const{ return _osr_bci != InvocationEntryBci; }
   int       start_bci() const  { return is_osr_flow()? _osr_bci: 0; }
   int       max_locals() const { return _max_locals; }
   int       max_stack() const  { return _max_stack; }
   int       max_cells() const  { return _max_locals + _max_stack; }
   int       code_size() const  { return _code_size; }
   bool      has_irreducible_entry() const { return _has_irreducible_entry; }
   // Represents information about an "active" jsr call.  This
   // class represents a call to the routine at some entry address
   // with some distinct return address.
   class JsrRecord : public ResourceObj {
   private:
     int _entry_address;
     int _return_address;
   public:
     JsrRecord(int entry_address, int return_address) {
       _entry_address = entry_address;
       _return_address = return_address;
     }
     int entry_address() const  { return _entry_address; }
     int return_address() const { return _return_address; }
     void print_on(outputStream* st) const {
 #ifndef PRODUCT
       st->print("%d->%d", entry_address(), return_address());
 #endif
     }
   };
   // A JsrSet represents some set of JsrRecords.  This class
   // is used to record a set of all jsr routines which we permit
   // execution to return (ret) from.
   //
   // During abstract interpretation, JsrSets are used to determine
   // whether two paths which reach a given block are unique, and
   // should be cloned apart, or are compatible, and should merge
   // together.
   //
   // Note that different amounts of effort can be expended determining
   // if paths are compatible.  <DISCUSSION>
   class JsrSet : public ResourceObj {
   private:
     GrowableArray<JsrRecord*>* _set;
     JsrRecord* record_at(int i) {
       return _set->at(i);
     }
     // Insert the given JsrRecord into the JsrSet, maintaining the order
     // of the set and replacing any element with the same entry address.
     void insert_jsr_record(JsrRecord* record);
     // Remove the JsrRecord with the given return address from the JsrSet.
     void remove_jsr_record(int return_address);
   public:
     JsrSet(Arena* arena, int default_len = 4);
     // Copy this JsrSet.
     void copy_into(JsrSet* jsrs);
     // Is this JsrSet compatible with some other JsrSet?
     bool is_compatible_with(JsrSet* other);
     // Apply the effect of a single bytecode to the JsrSet.
     void apply_control(ciTypeFlow* analyzer,
                        ciBytecodeStream* str,
                        StateVector* state);
     // What is the cardinality of this set?
     int size() const { return _set->length(); }
     void print_on(outputStream* st) const PRODUCT_RETURN;
   };
   class LocalSet VALUE_OBJ_CLASS_SPEC {
   private:
     enum Constants { max = 63 };
     uint64_t _bits;
   public:
     LocalSet() : _bits(0) {}
     void add(uint32_t i)        { if (i < (uint32_t)max) _bits |=  (1LL << i); }
     void add(LocalSet* ls)      { _bits |= ls->_bits; }
     bool test(uint32_t i) const { return i < (uint32_t)max ? (_bits>>i)&1U : true; }
     void clear()                { _bits = 0; }
     void print_on(outputStream* st, int limit) const  PRODUCT_RETURN;
   };
   // Used as a combined index for locals and temps
   enum Cell {
     Cell_0, Cell_max = INT_MAX
   };
   // A StateVector summarizes the type information at some
   // point in the program
   class StateVector : public ResourceObj {
   private:
     ciType**    _types;
     int         _stack_size;
     int         _monitor_count;
     ciTypeFlow* _outer;
     int         _trap_bci;
     int         _trap_index;
     LocalSet    _def_locals;  // For entire block
     static ciType* type_meet_internal(ciType* t1, ciType* t2, ciTypeFlow* analyzer);
   public:
     // Special elements in our type lattice.
     enum {
       T_TOP     = T_VOID,      // why not?
       T_BOTTOM  = T_CONFLICT,
       T_LONG2   = T_SHORT,     // 2nd word of T_LONG
       T_DOUBLE2 = T_CHAR,      // 2nd word of T_DOUBLE
       T_NULL    = T_BYTE       // for now.
     };
     static ciType* top_type()    { return ciType::make((BasicType)T_TOP); }
     static ciType* bottom_type() { return ciType::make((BasicType)T_BOTTOM); }
     static ciType* long2_type()  { return ciType::make((BasicType)T_LONG2); }
     static ciType* double2_type(){ return ciType::make((BasicType)T_DOUBLE2); }
     static ciType* null_type()   { return ciType::make((BasicType)T_NULL); }
     static ciType* half_type(ciType* t) {
       switch (t->basic_type()) {
       case T_LONG:    return long2_type();
       case T_DOUBLE:  return double2_type();
       default:        ShouldNotReachHere(); return NULL;
       }
     }
     // The meet operation for our type lattice.
     ciType* type_meet(ciType* t1, ciType* t2) {
       return type_meet_internal(t1, t2, outer());
     }
     // Accessors
     ciTypeFlow* outer() const          { return _outer; }
     int         stack_size() const     { return _stack_size; }
     void    set_stack_size(int ss)     { _stack_size = ss; }
     int         monitor_count() const  { return _monitor_count; }
     void    set_monitor_count(int mc)  { _monitor_count = mc; }
     LocalSet* def_locals() { return &_def_locals; }
     const LocalSet* def_locals() const { return &_def_locals; }
     static Cell start_cell()           { return (Cell)0; }
     static Cell next_cell(Cell c)      { return (Cell)(((int)c) + 1); }
     Cell        limit_cell() const {
       return (Cell)(outer()->max_locals() + stack_size());
     }
     // Cell creation
     Cell      local(int lnum) const {
       assert(lnum < outer()->max_locals(), "index check");
       return (Cell)(lnum);
     }
     Cell      stack(int snum) const {
       assert(snum < stack_size(), "index check");
       return (Cell)(outer()->max_locals() + snum);
     }
     Cell      tos() const { return stack(stack_size()-1); }
     // For external use only:
     ciType* local_type_at(int i) const { return type_at(local(i)); }
     ciType* stack_type_at(int i) const { return type_at(stack(i)); }
     // Accessors for the type of some Cell c
     ciType*   type_at(Cell c) const {
       assert(start_cell() <= c && c < limit_cell(), "out of bounds");
       return _types[c];
     }
     void      set_type_at(Cell c, ciType* type) {
       assert(start_cell() <= c && c < limit_cell(), "out of bounds");
       _types[c] = type;
     }
     // Top-of-stack operations.
     void      set_type_at_tos(ciType* type) { set_type_at(tos(), type); }
     ciType*   type_at_tos() const           { return type_at(tos()); }
     void      push(ciType* type) {
       _stack_size++;
       set_type_at_tos(type);
     }
     void      pop() {
       debug_only(set_type_at_tos(bottom_type()));
       _stack_size--;
     }
     ciType*   pop_value() {
       ciType* t = type_at_tos();
       pop();
       return t;
     }
     // Convenience operations.
     bool      is_reference(ciType* type) const {
       return type == null_type() || !type->is_primitive_type();
     }
     bool      is_int(ciType* type) const {
       return type->basic_type() == T_INT;
     }
     bool      is_long(ciType* type) const {
       return type->basic_type() == T_LONG;
     }
     bool      is_float(ciType* type) const {
       return type->basic_type() == T_FLOAT;
     }
     bool      is_double(ciType* type) const {
       return type->basic_type() == T_DOUBLE;
     }
     void store_to_local(int lnum) {
       _def_locals.add((uint) lnum);
     }
     void      push_translate(ciType* type);
     void      push_int() {
       push(ciType::make(T_INT));
     }
     void      pop_int() {
       assert(is_int(type_at_tos()), "must be integer");
       pop();
     }
     void      check_int(Cell c) {
       assert(is_int(type_at(c)), "must be integer");
     }
     void      push_double() {
       push(ciType::make(T_DOUBLE));
       push(double2_type());
     }
     void      pop_double() {
       assert(type_at_tos() == double2_type(), "must be 2nd half");
       pop();
       assert(is_double(type_at_tos()), "must be double");
       pop();
     }
     void      push_float() {
       push(ciType::make(T_FLOAT));
     }
     void      pop_float() {
       assert(is_float(type_at_tos()), "must be float");
       pop();
     }
     void      push_long() {
       push(ciType::make(T_LONG));
       push(long2_type());
     }
     void      pop_long() {
       assert(type_at_tos() == long2_type(), "must be 2nd half");
       pop();
       assert(is_long(type_at_tos()), "must be long");
       pop();
     }
     void      push_object(ciKlass* klass) {
       push(klass);
     }
     void      pop_object() {
       assert(is_reference(type_at_tos()), "must be reference type");
       pop();
     }
     void      pop_array() {
       assert(type_at_tos() == null_type() ||
              type_at_tos()->is_array_klass(), "must be array type");
       pop();
     }
     // pop_objArray and pop_typeArray narrow the tos to ciObjArrayKlass
     // or ciTypeArrayKlass (resp.).  In the rare case that an explicit
     // null is popped from the stack, we return NULL.  Caller beware.
     ciObjArrayKlass* pop_objArray() {
       ciType* array = pop_value();
       if (array == null_type())  return NULL;
       assert(array->is_obj_array_klass(), "must be object array type");
       return array->as_obj_array_klass();
     }
     ciTypeArrayKlass* pop_typeArray() {
       ciType* array = pop_value();
       if (array == null_type())  return NULL;
       assert(array->is_type_array_klass(), "must be prim array type");
       return array->as_type_array_klass();
     }
     void      push_null() {
       push(null_type());
     }
     void      do_null_assert(ciKlass* unloaded_klass);
     // Helper convenience routines.
     void do_aaload(ciBytecodeStream* str);
     void do_checkcast(ciBytecodeStream* str);
     void do_getfield(ciBytecodeStream* str);
     void do_getstatic(ciBytecodeStream* str);
     void do_invoke(ciBytecodeStream* str, bool has_receiver);
     void do_jsr(ciBytecodeStream* str);
     void do_ldc(ciBytecodeStream* str);
     void do_multianewarray(ciBytecodeStream* str);
     void do_new(ciBytecodeStream* str);
     void do_newarray(ciBytecodeStream* str);
     void do_putfield(ciBytecodeStream* str);
     void do_putstatic(ciBytecodeStream* str);
     void do_ret(ciBytecodeStream* str);
     void overwrite_local_double_long(int index) {
       // Invalidate the previous local if it contains first half of
       // a double or long value since it's seconf half is being overwritten.
       int prev_index = index - 1;
       if (prev_index >= 0 &&
           (is_double(type_at(local(prev_index))) ||
            is_long(type_at(local(prev_index))))) {
         set_type_at(local(prev_index), bottom_type());
       }
     }
     void load_local_object(int index) {
       ciType* type = type_at(local(index));
       assert(is_reference(type), "must be reference type");
       push(type);
     }
     void store_local_object(int index) {
       ciType* type = pop_value();
       assert(is_reference(type) || type->is_return_address(),
              "must be reference type or return address");
       overwrite_local_double_long(index);
       set_type_at(local(index), type);
       store_to_local(index);
     }
     void load_local_double(int index) {
       ciType* type = type_at(local(index));
       ciType* type2 = type_at(local(index+1));
       assert(is_double(type), "must be double type");
       assert(type2 == double2_type(), "must be 2nd half");
       push(type);
       push(double2_type());
     }
     void store_local_double(int index) {
       ciType* type2 = pop_value();
       ciType* type = pop_value();
       assert(is_double(type), "must be double");
       assert(type2 == double2_type(), "must be 2nd half");
       overwrite_local_double_long(index);
       set_type_at(local(index), type);
       set_type_at(local(index+1), type2);
       store_to_local(index);
       store_to_local(index+1);
     }
     void load_local_float(int index) {
       ciType* type = type_at(local(index));
       assert(is_float(type), "must be float type");
       push(type);
     }
     void store_local_float(int index) {
       ciType* type = pop_value();
       assert(is_float(type), "must be float type");
       overwrite_local_double_long(index);
       set_type_at(local(index), type);
       store_to_local(index);
     }
     void load_local_int(int index) {
       ciType* type = type_at(local(index));
       assert(is_int(type), "must be int type");
       push(type);
     }
     void store_local_int(int index) {
       ciType* type = pop_value();
       assert(is_int(type), "must be int type");
       overwrite_local_double_long(index);
       set_type_at(local(index), type);
       store_to_local(index);
     }
     void load_local_long(int index) {
       ciType* type = type_at(local(index));
       ciType* type2 = type_at(local(index+1));
       assert(is_long(type), "must be long type");
       assert(type2 == long2_type(), "must be 2nd half");
       push(type);
       push(long2_type());
     }
     void store_local_long(int index) {
       ciType* type2 = pop_value();
       ciType* type = pop_value();
       assert(is_long(type), "must be long");
       assert(type2 == long2_type(), "must be 2nd half");
       overwrite_local_double_long(index);
       set_type_at(local(index), type);
       set_type_at(local(index+1), type2);
       store_to_local(index);
       store_to_local(index+1);
     }
     // Stop interpretation of this path with a trap.
     void trap(ciBytecodeStream* str, ciKlass* klass, int index);
   public:
     StateVector(ciTypeFlow* outer);
     // Copy our value into some other StateVector
     void copy_into(StateVector* copy) const;
     // Meets this StateVector with another, destructively modifying this
     // one.  Returns true if any modification takes place.
     bool meet(const StateVector* incoming);
     // Ditto, except that the incoming state is coming from an exception.
     bool meet_exception(ciInstanceKlass* exc, const StateVector* incoming);
     // Apply the effect of one bytecode to this StateVector
     bool apply_one_bytecode(ciBytecodeStream* stream);
     // What is the bci of the trap?
     int  trap_bci() { return _trap_bci; }
     // What is the index associated with the trap?
     int  trap_index() { return _trap_index; }
     void print_cell_on(outputStream* st, Cell c) const PRODUCT_RETURN;
     void print_on(outputStream* st) const              PRODUCT_RETURN;
   };
   // Parameter for "find_block" calls:
   // Describes the difference between a public and backedge copy.
   enum CreateOption {
     create_public_copy,
     create_backedge_copy,
     no_create
   };
   // Successor iterator
   class SuccIter : public StackObj {
   private:
     Block* _pred;
     int    _index;
     Block* _succ;
   public:
     SuccIter()                        : _pred(NULL), _index(-1), _succ(NULL) {}
     SuccIter(Block* pred)             : _pred(pred), _index(-1), _succ(NULL) { next(); }
     int    index()     { return _index; }
     Block* pred()      { return _pred; }           // Return predecessor
     bool   done()      { return _index < 0; }      // Finished?
     Block* succ()      { return _succ; }           // Return current successor
     void   next();                                 // Advance
     void   set_succ(Block* succ);                  // Update current successor
     bool   is_normal_ctrl() { return index() < _pred->successors()->length(); }
   };
   // A basic block
   class Block : public ResourceObj {
   private:
     ciBlock*                          _ciblock;
     GrowableArray<Block*>*           _exceptions;
     GrowableArray<ciInstanceKlass*>* _exc_klasses;
     GrowableArray<Block*>*           _successors;
     StateVector*                     _state;
     JsrSet*                          _jsrs;
     int                              _trap_bci;
     int                              _trap_index;
     // pre_order, assigned at first visit. Used as block ID and "visited" tag
     int                              _pre_order;
     // A post-order, used to compute the reverse post order (RPO) provided to the client
     int                              _post_order;  // used to compute rpo
     // Has this block been cloned for a loop backedge?
     bool                             _backedge_copy;
     // A pointer used for our internal work list
     Block*                           _next;
     bool                             _on_work_list;      // on the work list
     Block*                           _rpo_next;          // Reverse post order list
     // Loop info
     Loop*                            _loop;              // nearest loop
     bool                             _irreducible_entry; // entry to irreducible loop
     bool                             _exception_entry;   // entry to exception handler
     ciBlock*     ciblock() const     { return _ciblock; }
     StateVector* state() const     { return _state; }
     // Compute the exceptional successors and types for this Block.
     void compute_exceptions();
   public:
     // constructors
     Block(ciTypeFlow* outer, ciBlock* ciblk, JsrSet* jsrs);
     void set_trap(int trap_bci, int trap_index) {
       _trap_bci = trap_bci;
       _trap_index = trap_index;
       assert(has_trap(), "");
     }
     bool has_trap()   const  { return _trap_bci != -1; }
     int  trap_bci()   const  { assert(has_trap(), ""); return _trap_bci; }
     int  trap_index() const  { assert(has_trap(), ""); return _trap_index; }
     // accessors
     ciTypeFlow* outer() const { return state()->outer(); }
     int start() const         { return _ciblock->start_bci(); }
     int limit() const         { return _ciblock->limit_bci(); }
     int control() const       { return _ciblock->control_bci(); }
     JsrSet* jsrs() const      { return _jsrs; }
     bool    is_backedge_copy() const       { return _backedge_copy; }
     void   set_backedge_copy(bool z);
     int        backedge_copy_count() const { return outer()->backedge_copy_count(ciblock()->index(), _jsrs); }
     // access to entry state
     int     stack_size() const         { return _state->stack_size(); }
     int     monitor_count() const      { return _state->monitor_count(); }
     ciType* local_type_at(int i) const { return _state->local_type_at(i); }
     ciType* stack_type_at(int i) const { return _state->stack_type_at(i); }
     // Data flow on locals
     bool is_invariant_local(uint v) const {
       assert(is_loop_head(), "only loop heads");
       // Find outermost loop with same loop head
       Loop* lp = loop();
       while (lp->parent() != NULL) {
         if (lp->parent()->head() != lp->head()) break;
         lp = lp->parent();
       }
       return !lp->def_locals()->test(v);
     }
     LocalSet* def_locals() { return _state->def_locals(); }
     const LocalSet* def_locals() const { return _state->def_locals(); }
     // Get the successors for this Block.
     GrowableArray<Block*>* successors(ciBytecodeStream* str,
                                       StateVector* state,
                                       JsrSet* jsrs);
     GrowableArray<Block*>* successors() {
       assert(_successors != NULL, "must be filled in");
       return _successors;
     }
     // Get the exceptional successors for this Block.
     GrowableArray<Block*>* exceptions() {
       if (_exceptions == NULL) {
         compute_exceptions();
       }
       return _exceptions;
     }
     // Get the exception klasses corresponding to the
     // exceptional successors for this Block.
     GrowableArray<ciInstanceKlass*>* exc_klasses() {
       if (_exc_klasses == NULL) {
         compute_exceptions();
       }
       return _exc_klasses;
     }
     // Is this Block compatible with a given JsrSet?
     bool is_compatible_with(JsrSet* other) {
       return _jsrs->is_compatible_with(other);
     }
     // Copy the value of our state vector into another.
     void copy_state_into(StateVector* copy) const {
       _state->copy_into(copy);
     }
     // Copy the value of our JsrSet into another
     void copy_jsrs_into(JsrSet* copy) const {
       _jsrs->copy_into(copy);
     }
     // Meets the start state of this block with another state, destructively
     // modifying this one.  Returns true if any modification takes place.
     bool meet(const StateVector* incoming) {
       return state()->meet(incoming);
     }
     // Ditto, except that the incoming state is coming from an
     // exception path.  This means the stack is replaced by the
     // appropriate exception type.
     bool meet_exception(ciInstanceKlass* exc, const StateVector* incoming) {
       return state()->meet_exception(exc, incoming);
     }
     // Work list manipulation
     void   set_next(Block* block) { _next = block; }
     Block* next() const           { return _next; }
     void   set_on_work_list(bool c) { _on_work_list = c; }
     bool   is_on_work_list() const  { return _on_work_list; }
     bool   has_pre_order() const  { return _pre_order >= 0; }
     void   set_pre_order(int po)  { assert(!has_pre_order(), ""); _pre_order = po; }
     int    pre_order() const      { assert(has_pre_order(), ""); return _pre_order; }
     void   set_next_pre_order()   { set_pre_order(outer()->inc_next_pre_order()); }
     bool   is_start() const       { return _pre_order == outer()->start_block_num(); }
     // Reverse post order
     void   df_init();
     bool   has_post_order() const { return _post_order >= 0; }
     void   set_post_order(int po) { assert(!has_post_order() && po >= 0, ""); _post_order = po; }
     void   reset_post_order(int o){ _post_order = o; }
     int    post_order() const     { assert(has_post_order(), ""); return _post_order; }
     bool   has_rpo() const        { return has_post_order() && outer()->have_block_count(); }
     int    rpo() const            { assert(has_rpo(), ""); return outer()->block_count() - post_order() - 1; }
     void   set_rpo_next(Block* b) { _rpo_next = b; }
     Block* rpo_next()             { return _rpo_next; }
     // Loops
     Loop*  loop() const                  { return _loop; }
     void   set_loop(Loop* lp)            { _loop = lp; }
     bool   is_loop_head() const          { return _loop && _loop->head() == this; }
     void   set_irreducible_entry(bool c) { _irreducible_entry = c; }
     bool   is_irreducible_entry() const  { return _irreducible_entry; }
     bool   is_visited() const            { return has_pre_order(); }
     bool   is_post_visited() const       { return has_post_order(); }
     bool   is_clonable_exit(Loop* lp);
     Block* looping_succ(Loop* lp);       // Successor inside of loop
     bool   is_single_entry_loop_head() const {
       if (!is_loop_head()) return false;
       for (Loop* lp = loop(); lp != NULL && lp->head() == this; lp = lp->parent())
         if (lp->is_irreducible()) return false;
       return true;
     }
     void   print_value_on(outputStream* st) const PRODUCT_RETURN;
     void   print_on(outputStream* st) const       PRODUCT_RETURN;
   };
   // Loop
   class Loop : public ResourceObj {
   private:
     Loop* _parent;
     Loop* _sibling;  // List of siblings, null terminated
     Loop* _child;    // Head of child list threaded thru sibling pointer
     Block* _head;    // Head of loop
     Block* _tail;    // Tail of loop
     bool   _irreducible;
     LocalSet _def_locals;
   public:
     Loop(Block* head, Block* tail) :
       _head(head),   _tail(tail),
       _parent(NULL), _sibling(NULL), _child(NULL),
       _irreducible(false), _def_locals() {}
     Loop* parent()  const { return _parent; }
     Loop* sibling() const { return _sibling; }
     Loop* child()   const { return _child; }
     Block* head()   const { return _head; }
     Block* tail()   const { return _tail; }
     void set_parent(Loop* p)  { _parent = p; }
     void set_sibling(Loop* s) { _sibling = s; }
     void set_child(Loop* c)   { _child = c; }
     void set_head(Block* hd)  { _head = hd; }
     void set_tail(Block* tl)  { _tail = tl; }
     int depth() const;              // nesting depth
     // Returns true if lp is a nested loop or us.
     bool contains(Loop* lp) const;
     bool contains(Block* blk) const { return contains(blk->loop()); }
     // Data flow on locals
     LocalSet* def_locals() { return &_def_locals; }
     const LocalSet* def_locals() const { return &_def_locals; }
     // Merge the branch lp into this branch, sorting on the loop head
     // pre_orders. Returns the new branch.
     Loop* sorted_merge(Loop* lp);
     // Mark non-single entry to loop
     void set_irreducible(Block* entry) {
       _irreducible = true;
       entry->set_irreducible_entry(true);
     }
     bool is_irreducible() const { return _irreducible; }
     bool is_root() const { return _tail->pre_order() == max_jint; }
     void print(outputStream* st = tty, int indent = 0) const PRODUCT_RETURN;
   };
   // Postorder iteration over the loop tree.
   class PostorderLoops : public StackObj {
   private:
     Loop* _root;
     Loop* _current;
   public:
     PostorderLoops(Loop* root) : _root(root), _current(root) {
       while (_current->child() != NULL) {
         _current = _current->child();
       }
     }
     bool done() { return _current == NULL; }  // Finished iterating?
     void next();                            // Advance to next loop
     Loop* current() { return _current; }      // Return current loop.
   };
   // Preorder iteration over the loop tree.
   class PreorderLoops : public StackObj {
   private:
     Loop* _root;
     Loop* _current;
   public:
     PreorderLoops(Loop* root) : _root(root), _current(root) {}
     bool done() { return _current == NULL; }  // Finished iterating?
     void next();                            // Advance to next loop
     Loop* current() { return _current; }      // Return current loop.
   };
   // Standard indexes of successors, for various bytecodes.
   enum {
     FALL_THROUGH   = 0,  // normal control
     IF_NOT_TAKEN   = 0,  // the not-taken branch of an if (i.e., fall-through)
     IF_TAKEN       = 1,  // the taken branch of an if
     GOTO_TARGET    = 0,  // unique successor for goto, jsr, or ret
     SWITCH_DEFAULT = 0,  // default branch of a switch
     SWITCH_CASES   = 1   // first index for any non-default switch branches
     // Unlike in other blocks, the successors of a switch are listed uniquely.
   };
 private:
   // A mapping from pre_order to Blocks.  This array is created
   // only at the end of the flow.
   Block** _block_map;
   // For each ciBlock index, a list of Blocks which share this ciBlock.
   GrowableArray<Block*>** _idx_to_blocklist;
   // count of ciBlocks
   int _ciblock_count;
   // Tells if a given instruction is able to generate an exception edge.
   bool can_trap(ciBytecodeStream& str);
   // Clone the loop heads. Returns true if any cloning occurred.
   bool clone_loop_heads(Loop* lp, StateVector* temp_vector, JsrSet* temp_set);
   // Clone lp's head and replace tail's successors with clone.
   Block* clone_loop_head(Loop* lp, StateVector* temp_vector, JsrSet* temp_set);
 public:
   // Return the block beginning at bci which has a JsrSet compatible
   // with jsrs.
   Block* block_at(int bci, JsrSet* set, CreateOption option = create_public_copy);
   // block factory
   Block* get_block_for(int ciBlockIndex, JsrSet* jsrs, CreateOption option = create_public_copy);
   // How many of the blocks have the backedge_copy bit set?
   int backedge_copy_count(int ciBlockIndex, JsrSet* jsrs) const;
   // Return an existing block containing bci which has a JsrSet compatible
   // with jsrs, or NULL if there is none.
   Block* existing_block_at(int bci, JsrSet* set) { return block_at(bci, set, no_create); }
   // Tell whether the flow analysis has encountered an error of some sort.
   bool failing() { return env()->failing() || _failure_reason != NULL; }
   // Reason this compilation is failing, such as "too many basic blocks".
   const char* failure_reason() { return _failure_reason; }
   // Note a failure.
   void record_failure(const char* reason);
   // Return the block of a given pre-order number.
   int have_block_count() const      { return _block_map != NULL; }
   int block_count() const           { assert(have_block_count(), "");
                                       return _next_pre_order; }
   Block* pre_order_at(int po) const { assert(0 <= po && po < block_count(), "out of bounds");
                                       return _block_map[po]; }
   Block* start_block() const        { return pre_order_at(start_block_num()); }
   int start_block_num() const       { return 0; }
   Block* rpo_at(int rpo) const      { assert(0 <= rpo && rpo < block_count(), "out of bounds");
                                       return _block_map[rpo]; }
   int next_pre_order()              { return _next_pre_order; }
   int inc_next_pre_order()          { return _next_pre_order++; }
 private:
   // A work list used during flow analysis.
   Block* _work_list;
   // List of blocks in reverse post order
   Block* _rpo_list;
   // Next Block::_pre_order.  After mapping, doubles as block_count.
   int _next_pre_order;
   // Are there more blocks on the work list?
   bool work_list_empty() { return _work_list == NULL; }
   // Get the next basic block from our work list.
   Block* work_list_next();
   // Add a basic block to our work list.
   void add_to_work_list(Block* block);
   // Prepend a basic block to rpo list.
   void prepend_to_rpo_list(Block* blk) {
     blk->set_rpo_next(_rpo_list);
     _rpo_list = blk;
   }
   // Root of the loop tree
   Loop* _loop_tree_root;
   // State used for make_jsr_record
   int _jsr_count;
   GrowableArray<JsrRecord*>* _jsr_records;
 public:
   // Make a JsrRecord for a given (entry, return) pair, if such a record
   // does not already exist.
   JsrRecord* make_jsr_record(int entry_address, int return_address);
   void  set_loop_tree_root(Loop* ltr) { _loop_tree_root = ltr; }
   Loop* loop_tree_root()              { return _loop_tree_root; }
 private:
   // Get the initial state for start_bci:
   const StateVector* get_start_state();
   // Merge the current state into all exceptional successors at the
   // current point in the code.
   void flow_exceptions(GrowableArray<Block*>* exceptions,
                        GrowableArray<ciInstanceKlass*>* exc_klasses,
                        StateVector* state);
   // Merge the current state into all successors at the current point
   // in the code.
   void flow_successors(GrowableArray<Block*>* successors,
                        StateVector* state);
   // Interpret the effects of the bytecodes on the incoming state
   // vector of a basic block.  Push the changed state to succeeding
   // basic blocks.
   void flow_block(Block* block,
                   StateVector* scratch_state,
                   JsrSet* scratch_jsrs);
   // Perform the type flow analysis, creating and cloning Blocks as
   // necessary.
   void flow_types();
   // Perform the depth first type flow analysis. Helper for flow_types.
   void df_flow_types(Block* start,
                      bool do_flow,
                      StateVector* temp_vector,
                      JsrSet* temp_set);
   // Incrementally build loop tree.
   void build_loop_tree(Block* blk);
   // Create the block map, which indexes blocks in pre_order.
   void map_blocks();
 public:
   // Perform type inference flow analysis.
   void do_flow();
   void print_on(outputStream* st) const PRODUCT_RETURN;
   void rpo_print_on(outputStream* st) const PRODUCT_RETURN;
 };

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/ci/ciTypeFlow.hpp@4ce7240d622c (annotated)

src/share/vm/ci/ciTypeFlow.hpp