aoqi@0: /*
aoqi@0:  * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #ifndef SHARE_VM_CI_CITYPEFLOW_HPP
aoqi@0: #define SHARE_VM_CI_CITYPEFLOW_HPP
aoqi@0: 
aoqi@0: #ifdef COMPILER2
aoqi@0: #include "ci/ciEnv.hpp"
aoqi@0: #include "ci/ciKlass.hpp"
aoqi@0: #include "ci/ciMethodBlocks.hpp"
aoqi@0: #endif
aoqi@0: #ifdef SHARK
aoqi@0: #include "ci/ciEnv.hpp"
aoqi@0: #include "ci/ciKlass.hpp"
aoqi@0: #include "ci/ciMethodBlocks.hpp"
aoqi@0: #include "shark/shark_globals.hpp"
aoqi@0: #endif
aoqi@0: 
aoqi@0: 
aoqi@0: class ciTypeFlow : public ResourceObj {
aoqi@0: private:
aoqi@0:   ciEnv*    _env;
aoqi@0:   ciMethod* _method;
aoqi@0:   ciMethodBlocks* _methodBlocks;
aoqi@0:   int       _osr_bci;
aoqi@0: 
aoqi@0:   // information cached from the method:
aoqi@0:   int _max_locals;
aoqi@0:   int _max_stack;
aoqi@0:   int _code_size;
aoqi@0:   bool      _has_irreducible_entry;
aoqi@0: 
aoqi@0:   const char* _failure_reason;
aoqi@0: 
aoqi@0: public:
aoqi@0:   class StateVector;
aoqi@0:   class Loop;
aoqi@0:   class Block;
aoqi@0: 
aoqi@0:   // Build a type flow analyzer
aoqi@0:   // Do an OSR analysis if osr_bci >= 0.
aoqi@0:   ciTypeFlow(ciEnv* env, ciMethod* method, int osr_bci = InvocationEntryBci);
aoqi@0: 
aoqi@0:   // Accessors
aoqi@0:   ciMethod* method() const     { return _method; }
aoqi@0:   ciEnv*    env()              { return _env; }
aoqi@0:   Arena*    arena()            { return _env->arena(); }
aoqi@0:   bool      is_osr_flow() const{ return _osr_bci != InvocationEntryBci; }
aoqi@0:   int       start_bci() const  { return is_osr_flow()? _osr_bci: 0; }
aoqi@0:   int       max_locals() const { return _max_locals; }
aoqi@0:   int       max_stack() const  { return _max_stack; }
aoqi@0:   int       max_cells() const  { return _max_locals + _max_stack; }
aoqi@0:   int       code_size() const  { return _code_size; }
aoqi@0:   bool      has_irreducible_entry() const { return _has_irreducible_entry; }
aoqi@0: 
aoqi@0:   // Represents information about an "active" jsr call.  This
aoqi@0:   // class represents a call to the routine at some entry address
aoqi@0:   // with some distinct return address.
aoqi@0:   class JsrRecord : public ResourceObj {
aoqi@0:   private:
aoqi@0:     int _entry_address;
aoqi@0:     int _return_address;
aoqi@0:   public:
aoqi@0:     JsrRecord(int entry_address, int return_address) {
aoqi@0:       _entry_address = entry_address;
aoqi@0:       _return_address = return_address;
aoqi@0:     }
aoqi@0: 
aoqi@0:     int entry_address() const  { return _entry_address; }
aoqi@0:     int return_address() const { return _return_address; }
aoqi@0: 
aoqi@0:     void print_on(outputStream* st) const {
aoqi@0: #ifndef PRODUCT
aoqi@0:       st->print("%d->%d", entry_address(), return_address());
aoqi@0: #endif
aoqi@0:     }
aoqi@0:   };
aoqi@0: 
aoqi@0:   // A JsrSet represents some set of JsrRecords.  This class
aoqi@0:   // is used to record a set of all jsr routines which we permit
aoqi@0:   // execution to return (ret) from.
aoqi@0:   //
aoqi@0:   // During abstract interpretation, JsrSets are used to determine
aoqi@0:   // whether two paths which reach a given block are unique, and
aoqi@0:   // should be cloned apart, or are compatible, and should merge
aoqi@0:   // together.
aoqi@0:   //
aoqi@0:   // Note that different amounts of effort can be expended determining
aoqi@0:   // if paths are compatible.  <DISCUSSION>
aoqi@0:   class JsrSet : public ResourceObj {
aoqi@0:   private:
aoqi@0:     GrowableArray<JsrRecord*>* _set;
aoqi@0: 
aoqi@0:     JsrRecord* record_at(int i) {
aoqi@0:       return _set->at(i);
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Insert the given JsrRecord into the JsrSet, maintaining the order
aoqi@0:     // of the set and replacing any element with the same entry address.
aoqi@0:     void insert_jsr_record(JsrRecord* record);
aoqi@0: 
aoqi@0:     // Remove the JsrRecord with the given return address from the JsrSet.
aoqi@0:     void remove_jsr_record(int return_address);
aoqi@0: 
aoqi@0:   public:
aoqi@0:     JsrSet(Arena* arena, int default_len = 4);
aoqi@0: 
aoqi@0:     // Copy this JsrSet.
aoqi@0:     void copy_into(JsrSet* jsrs);
aoqi@0: 
aoqi@0:     // Is this JsrSet compatible with some other JsrSet?
aoqi@0:     bool is_compatible_with(JsrSet* other);
aoqi@0: 
aoqi@0:     // Apply the effect of a single bytecode to the JsrSet.
aoqi@0:     void apply_control(ciTypeFlow* analyzer,
aoqi@0:                        ciBytecodeStream* str,
aoqi@0:                        StateVector* state);
aoqi@0: 
aoqi@0:     // What is the cardinality of this set?
aoqi@0:     int size() const { return _set->length(); }
aoqi@0: 
aoqi@0:     void print_on(outputStream* st) const PRODUCT_RETURN;
aoqi@0:   };
aoqi@0: 
aoqi@0:   class LocalSet VALUE_OBJ_CLASS_SPEC {
aoqi@0:   private:
aoqi@0:     enum Constants { max = 63 };
aoqi@0:     uint64_t _bits;
aoqi@0:   public:
aoqi@0:     LocalSet() : _bits(0) {}
aoqi@0:     void add(uint32_t i)        { if (i < (uint32_t)max) _bits |=  (1LL << i); }
aoqi@0:     void add(LocalSet* ls)      { _bits |= ls->_bits; }
aoqi@0:     bool test(uint32_t i) const { return i < (uint32_t)max ? (_bits>>i)&1U : true; }
aoqi@0:     void clear()                { _bits = 0; }
aoqi@0:     void print_on(outputStream* st, int limit) const  PRODUCT_RETURN;
aoqi@0:   };
aoqi@0: 
aoqi@0:   // Used as a combined index for locals and temps
aoqi@0:   enum Cell {
aoqi@0:     Cell_0, Cell_max = INT_MAX
aoqi@0:   };
aoqi@0: 
aoqi@0:   // A StateVector summarizes the type information at some
aoqi@0:   // point in the program
aoqi@0:   class StateVector : public ResourceObj {
aoqi@0:   private:
aoqi@0:     ciType**    _types;
aoqi@0:     int         _stack_size;
aoqi@0:     int         _monitor_count;
aoqi@0:     ciTypeFlow* _outer;
aoqi@0: 
aoqi@0:     int         _trap_bci;
aoqi@0:     int         _trap_index;
aoqi@0: 
aoqi@0:     LocalSet    _def_locals;  // For entire block
aoqi@0: 
aoqi@0:     static ciType* type_meet_internal(ciType* t1, ciType* t2, ciTypeFlow* analyzer);
aoqi@0: 
aoqi@0:   public:
aoqi@0:     // Special elements in our type lattice.
aoqi@0:     enum {
aoqi@0:       T_TOP     = T_VOID,      // why not?
aoqi@0:       T_BOTTOM  = T_CONFLICT,
aoqi@0:       T_LONG2   = T_SHORT,     // 2nd word of T_LONG
aoqi@0:       T_DOUBLE2 = T_CHAR,      // 2nd word of T_DOUBLE
aoqi@0:       T_NULL    = T_BYTE       // for now.
aoqi@0:     };
aoqi@0:     static ciType* top_type()    { return ciType::make((BasicType)T_TOP); }
aoqi@0:     static ciType* bottom_type() { return ciType::make((BasicType)T_BOTTOM); }
aoqi@0:     static ciType* long2_type()  { return ciType::make((BasicType)T_LONG2); }
aoqi@0:     static ciType* double2_type(){ return ciType::make((BasicType)T_DOUBLE2); }
aoqi@0:     static ciType* null_type()   { return ciType::make((BasicType)T_NULL); }
aoqi@0: 
aoqi@0:     static ciType* half_type(ciType* t) {
aoqi@0:       switch (t->basic_type()) {
aoqi@0:       case T_LONG:    return long2_type();
aoqi@0:       case T_DOUBLE:  return double2_type();
aoqi@0:       default:        ShouldNotReachHere(); return NULL;
aoqi@0:       }
aoqi@0:     }
aoqi@0: 
aoqi@0:     // The meet operation for our type lattice.
aoqi@0:     ciType* type_meet(ciType* t1, ciType* t2) {
aoqi@0:       return type_meet_internal(t1, t2, outer());
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Accessors
aoqi@0:     ciTypeFlow* outer() const          { return _outer; }
aoqi@0: 
aoqi@0:     int         stack_size() const     { return _stack_size; }
aoqi@0:     void    set_stack_size(int ss)     { _stack_size = ss; }
aoqi@0: 
aoqi@0:     int         monitor_count() const  { return _monitor_count; }
aoqi@0:     void    set_monitor_count(int mc)  { _monitor_count = mc; }
aoqi@0: 
aoqi@0:     LocalSet* def_locals() { return &_def_locals; }
aoqi@0:     const LocalSet* def_locals() const { return &_def_locals; }
aoqi@0: 
aoqi@0:     static Cell start_cell()           { return (Cell)0; }
aoqi@0:     static Cell next_cell(Cell c)      { return (Cell)(((int)c) + 1); }
aoqi@0:     Cell        limit_cell() const {
aoqi@0:       return (Cell)(outer()->max_locals() + stack_size());
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Cell creation
aoqi@0:     Cell      local(int lnum) const {
aoqi@0:       assert(lnum < outer()->max_locals(), "index check");
aoqi@0:       return (Cell)(lnum);
aoqi@0:     }
aoqi@0: 
aoqi@0:     Cell      stack(int snum) const {
aoqi@0:       assert(snum < stack_size(), "index check");
aoqi@0:       return (Cell)(outer()->max_locals() + snum);
aoqi@0:     }
aoqi@0: 
aoqi@0:     Cell      tos() const { return stack(stack_size()-1); }
aoqi@0: 
aoqi@0:     // For external use only:
aoqi@0:     ciType* local_type_at(int i) const { return type_at(local(i)); }
aoqi@0:     ciType* stack_type_at(int i) const { return type_at(stack(i)); }
aoqi@0: 
aoqi@0:     // Accessors for the type of some Cell c
aoqi@0:     ciType*   type_at(Cell c) const {
aoqi@0:       assert(start_cell() <= c && c < limit_cell(), "out of bounds");
aoqi@0:       return _types[c];
aoqi@0:     }
aoqi@0: 
aoqi@0:     void      set_type_at(Cell c, ciType* type) {
aoqi@0:       assert(start_cell() <= c && c < limit_cell(), "out of bounds");
aoqi@0:       _types[c] = type;
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Top-of-stack operations.
aoqi@0:     void      set_type_at_tos(ciType* type) { set_type_at(tos(), type); }
aoqi@0:     ciType*   type_at_tos() const           { return type_at(tos()); }
aoqi@0: 
aoqi@0:     void      push(ciType* type) {
aoqi@0:       _stack_size++;
aoqi@0:       set_type_at_tos(type);
aoqi@0:     }
aoqi@0:     void      pop() {
aoqi@0:       debug_only(set_type_at_tos(bottom_type()));
aoqi@0:       _stack_size--;
aoqi@0:     }
aoqi@0:     ciType*   pop_value() {
aoqi@0:       ciType* t = type_at_tos();
aoqi@0:       pop();
aoqi@0:       return t;
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Convenience operations.
aoqi@0:     bool      is_reference(ciType* type) const {
aoqi@0:       return type == null_type() || !type->is_primitive_type();
aoqi@0:     }
aoqi@0:     bool      is_int(ciType* type) const {
aoqi@0:       return type->basic_type() == T_INT;
aoqi@0:     }
aoqi@0:     bool      is_long(ciType* type) const {
aoqi@0:       return type->basic_type() == T_LONG;
aoqi@0:     }
aoqi@0:     bool      is_float(ciType* type) const {
aoqi@0:       return type->basic_type() == T_FLOAT;
aoqi@0:     }
aoqi@0:     bool      is_double(ciType* type) const {
aoqi@0:       return type->basic_type() == T_DOUBLE;
aoqi@0:     }
aoqi@0: 
aoqi@0:     void store_to_local(int lnum) {
aoqi@0:       _def_locals.add((uint) lnum);
aoqi@0:     }
aoqi@0: 
aoqi@0:     void      push_translate(ciType* type);
aoqi@0: 
aoqi@0:     void      push_int() {
aoqi@0:       push(ciType::make(T_INT));
aoqi@0:     }
aoqi@0:     void      pop_int() {
aoqi@0:       assert(is_int(type_at_tos()), "must be integer");
aoqi@0:       pop();
aoqi@0:     }
aoqi@0:     void      check_int(Cell c) {
aoqi@0:       assert(is_int(type_at(c)), "must be integer");
aoqi@0:     }
aoqi@0:     void      push_double() {
aoqi@0:       push(ciType::make(T_DOUBLE));
aoqi@0:       push(double2_type());
aoqi@0:     }
aoqi@0:     void      pop_double() {
aoqi@0:       assert(type_at_tos() == double2_type(), "must be 2nd half");
aoqi@0:       pop();
aoqi@0:       assert(is_double(type_at_tos()), "must be double");
aoqi@0:       pop();
aoqi@0:     }
aoqi@0:     void      push_float() {
aoqi@0:       push(ciType::make(T_FLOAT));
aoqi@0:     }
aoqi@0:     void      pop_float() {
aoqi@0:       assert(is_float(type_at_tos()), "must be float");
aoqi@0:       pop();
aoqi@0:     }
aoqi@0:     void      push_long() {
aoqi@0:       push(ciType::make(T_LONG));
aoqi@0:       push(long2_type());
aoqi@0:     }
aoqi@0:     void      pop_long() {
aoqi@0:       assert(type_at_tos() == long2_type(), "must be 2nd half");
aoqi@0:       pop();
aoqi@0:       assert(is_long(type_at_tos()), "must be long");
aoqi@0:       pop();
aoqi@0:     }
aoqi@0:     void      push_object(ciKlass* klass) {
aoqi@0:       push(klass);
aoqi@0:     }
aoqi@0:     void      pop_object() {
aoqi@0:       assert(is_reference(type_at_tos()), "must be reference type");
aoqi@0:       pop();
aoqi@0:     }
aoqi@0:     void      pop_array() {
aoqi@0:       assert(type_at_tos() == null_type() ||
aoqi@0:              type_at_tos()->is_array_klass(), "must be array type");
aoqi@0:       pop();
aoqi@0:     }
aoqi@0:     // pop_objArray and pop_typeArray narrow the tos to ciObjArrayKlass
aoqi@0:     // or ciTypeArrayKlass (resp.).  In the rare case that an explicit
aoqi@0:     // null is popped from the stack, we return NULL.  Caller beware.
aoqi@0:     ciObjArrayKlass* pop_objArray() {
aoqi@0:       ciType* array = pop_value();
aoqi@0:       if (array == null_type())  return NULL;
aoqi@0:       assert(array->is_obj_array_klass(), "must be object array type");
aoqi@0:       return array->as_obj_array_klass();
aoqi@0:     }
aoqi@0:     ciTypeArrayKlass* pop_typeArray() {
aoqi@0:       ciType* array = pop_value();
aoqi@0:       if (array == null_type())  return NULL;
aoqi@0:       assert(array->is_type_array_klass(), "must be prim array type");
aoqi@0:       return array->as_type_array_klass();
aoqi@0:     }
aoqi@0:     void      push_null() {
aoqi@0:       push(null_type());
aoqi@0:     }
aoqi@0:     void      do_null_assert(ciKlass* unloaded_klass);
aoqi@0: 
aoqi@0:     // Helper convenience routines.
aoqi@0:     void do_aaload(ciBytecodeStream* str);
aoqi@0:     void do_checkcast(ciBytecodeStream* str);
aoqi@0:     void do_getfield(ciBytecodeStream* str);
aoqi@0:     void do_getstatic(ciBytecodeStream* str);
aoqi@0:     void do_invoke(ciBytecodeStream* str, bool has_receiver);
aoqi@0:     void do_jsr(ciBytecodeStream* str);
aoqi@0:     void do_ldc(ciBytecodeStream* str);
aoqi@0:     void do_multianewarray(ciBytecodeStream* str);
aoqi@0:     void do_new(ciBytecodeStream* str);
aoqi@0:     void do_newarray(ciBytecodeStream* str);
aoqi@0:     void do_putfield(ciBytecodeStream* str);
aoqi@0:     void do_putstatic(ciBytecodeStream* str);
aoqi@0:     void do_ret(ciBytecodeStream* str);
aoqi@0: 
aoqi@0:     void overwrite_local_double_long(int index) {
aoqi@0:       // Invalidate the previous local if it contains first half of
aoqi@0:       // a double or long value since it's seconf half is being overwritten.
aoqi@0:       int prev_index = index - 1;
aoqi@0:       if (prev_index >= 0 &&
aoqi@0:           (is_double(type_at(local(prev_index))) ||
aoqi@0:            is_long(type_at(local(prev_index))))) {
aoqi@0:         set_type_at(local(prev_index), bottom_type());
aoqi@0:       }
aoqi@0:     }
aoqi@0: 
aoqi@0:     void load_local_object(int index) {
aoqi@0:       ciType* type = type_at(local(index));
aoqi@0:       assert(is_reference(type), "must be reference type");
aoqi@0:       push(type);
aoqi@0:     }
aoqi@0:     void store_local_object(int index) {
aoqi@0:       ciType* type = pop_value();
aoqi@0:       assert(is_reference(type) || type->is_return_address(),
aoqi@0:              "must be reference type or return address");
aoqi@0:       overwrite_local_double_long(index);
aoqi@0:       set_type_at(local(index), type);
aoqi@0:       store_to_local(index);
aoqi@0:     }
aoqi@0: 
aoqi@0:     void load_local_double(int index) {
aoqi@0:       ciType* type = type_at(local(index));
aoqi@0:       ciType* type2 = type_at(local(index+1));
aoqi@0:       assert(is_double(type), "must be double type");
aoqi@0:       assert(type2 == double2_type(), "must be 2nd half");
aoqi@0:       push(type);
aoqi@0:       push(double2_type());
aoqi@0:     }
aoqi@0:     void store_local_double(int index) {
aoqi@0:       ciType* type2 = pop_value();
aoqi@0:       ciType* type = pop_value();
aoqi@0:       assert(is_double(type), "must be double");
aoqi@0:       assert(type2 == double2_type(), "must be 2nd half");
aoqi@0:       overwrite_local_double_long(index);
aoqi@0:       set_type_at(local(index), type);
aoqi@0:       set_type_at(local(index+1), type2);
aoqi@0:       store_to_local(index);
aoqi@0:       store_to_local(index+1);
aoqi@0:     }
aoqi@0: 
aoqi@0:     void load_local_float(int index) {
aoqi@0:       ciType* type = type_at(local(index));
aoqi@0:       assert(is_float(type), "must be float type");
aoqi@0:       push(type);
aoqi@0:     }
aoqi@0:     void store_local_float(int index) {
aoqi@0:       ciType* type = pop_value();
aoqi@0:       assert(is_float(type), "must be float type");
aoqi@0:       overwrite_local_double_long(index);
aoqi@0:       set_type_at(local(index), type);
aoqi@0:       store_to_local(index);
aoqi@0:     }
aoqi@0: 
aoqi@0:     void load_local_int(int index) {
aoqi@0:       ciType* type = type_at(local(index));
aoqi@0:       assert(is_int(type), "must be int type");
aoqi@0:       push(type);
aoqi@0:     }
aoqi@0:     void store_local_int(int index) {
aoqi@0:       ciType* type = pop_value();
aoqi@0:       assert(is_int(type), "must be int type");
aoqi@0:       overwrite_local_double_long(index);
aoqi@0:       set_type_at(local(index), type);
aoqi@0:       store_to_local(index);
aoqi@0:     }
aoqi@0: 
aoqi@0:     void load_local_long(int index) {
aoqi@0:       ciType* type = type_at(local(index));
aoqi@0:       ciType* type2 = type_at(local(index+1));
aoqi@0:       assert(is_long(type), "must be long type");
aoqi@0:       assert(type2 == long2_type(), "must be 2nd half");
aoqi@0:       push(type);
aoqi@0:       push(long2_type());
aoqi@0:     }
aoqi@0:     void store_local_long(int index) {
aoqi@0:       ciType* type2 = pop_value();
aoqi@0:       ciType* type = pop_value();
aoqi@0:       assert(is_long(type), "must be long");
aoqi@0:       assert(type2 == long2_type(), "must be 2nd half");
aoqi@0:       overwrite_local_double_long(index);
aoqi@0:       set_type_at(local(index), type);
aoqi@0:       set_type_at(local(index+1), type2);
aoqi@0:       store_to_local(index);
aoqi@0:       store_to_local(index+1);
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Stop interpretation of this path with a trap.
aoqi@0:     void trap(ciBytecodeStream* str, ciKlass* klass, int index);
aoqi@0: 
aoqi@0:   public:
aoqi@0:     StateVector(ciTypeFlow* outer);
aoqi@0: 
aoqi@0:     // Copy our value into some other StateVector
aoqi@0:     void copy_into(StateVector* copy) const;
aoqi@0: 
aoqi@0:     // Meets this StateVector with another, destructively modifying this
aoqi@0:     // one.  Returns true if any modification takes place.
aoqi@0:     bool meet(const StateVector* incoming);
aoqi@0: 
aoqi@0:     // Ditto, except that the incoming state is coming from an exception.
aoqi@0:     bool meet_exception(ciInstanceKlass* exc, const StateVector* incoming);
aoqi@0: 
aoqi@0:     // Apply the effect of one bytecode to this StateVector
aoqi@0:     bool apply_one_bytecode(ciBytecodeStream* stream);
aoqi@0: 
aoqi@0:     // What is the bci of the trap?
aoqi@0:     int  trap_bci() { return _trap_bci; }
aoqi@0: 
aoqi@0:     // What is the index associated with the trap?
aoqi@0:     int  trap_index() { return _trap_index; }
aoqi@0: 
aoqi@0:     void print_cell_on(outputStream* st, Cell c) const PRODUCT_RETURN;
aoqi@0:     void print_on(outputStream* st) const              PRODUCT_RETURN;
aoqi@0:   };
aoqi@0: 
aoqi@0:   // Parameter for "find_block" calls:
aoqi@0:   // Describes the difference between a public and backedge copy.
aoqi@0:   enum CreateOption {
aoqi@0:     create_public_copy,
aoqi@0:     create_backedge_copy,
aoqi@0:     no_create
aoqi@0:   };
aoqi@0: 
aoqi@0:   // Successor iterator
aoqi@0:   class SuccIter : public StackObj {
aoqi@0:   private:
aoqi@0:     Block* _pred;
aoqi@0:     int    _index;
aoqi@0:     Block* _succ;
aoqi@0:   public:
aoqi@0:     SuccIter()                        : _pred(NULL), _index(-1), _succ(NULL) {}
aoqi@0:     SuccIter(Block* pred)             : _pred(pred), _index(-1), _succ(NULL) { next(); }
aoqi@0:     int    index()     { return _index; }
aoqi@0:     Block* pred()      { return _pred; }           // Return predecessor
aoqi@0:     bool   done()      { return _index < 0; }      // Finished?
aoqi@0:     Block* succ()      { return _succ; }           // Return current successor
aoqi@0:     void   next();                                 // Advance
aoqi@0:     void   set_succ(Block* succ);                  // Update current successor
aoqi@0:     bool   is_normal_ctrl() { return index() < _pred->successors()->length(); }
aoqi@0:   };
aoqi@0: 
aoqi@0:   // A basic block
aoqi@0:   class Block : public ResourceObj {
aoqi@0:   private:
aoqi@0:     ciBlock*                          _ciblock;
aoqi@0:     GrowableArray<Block*>*           _exceptions;
aoqi@0:     GrowableArray<ciInstanceKlass*>* _exc_klasses;
aoqi@0:     GrowableArray<Block*>*           _successors;
aoqi@0:     StateVector*                     _state;
aoqi@0:     JsrSet*                          _jsrs;
aoqi@0: 
aoqi@0:     int                              _trap_bci;
aoqi@0:     int                              _trap_index;
aoqi@0: 
aoqi@0:     // pre_order, assigned at first visit. Used as block ID and "visited" tag
aoqi@0:     int                              _pre_order;
aoqi@0: 
aoqi@0:     // A post-order, used to compute the reverse post order (RPO) provided to the client
aoqi@0:     int                              _post_order;  // used to compute rpo
aoqi@0: 
aoqi@0:     // Has this block been cloned for a loop backedge?
aoqi@0:     bool                             _backedge_copy;
aoqi@0: 
aoqi@0:     // This block is entry to irreducible loop.
aoqi@0:     bool                             _irreducible_entry;
aoqi@0: 
aoqi@0:     // This block has monitor entry point.
aoqi@0:     bool                             _has_monitorenter;
aoqi@0: 
aoqi@0:     // A pointer used for our internal work list
aoqi@0:     bool                             _on_work_list;      // on the work list
aoqi@0:     Block*                           _next;
aoqi@0:     Block*                           _rpo_next;          // Reverse post order list
aoqi@0: 
aoqi@0:     // Loop info
aoqi@0:     Loop*                            _loop;              // nearest loop
aoqi@0: 
aoqi@0:     ciBlock*     ciblock() const     { return _ciblock; }
aoqi@0:     StateVector* state() const     { return _state; }
aoqi@0: 
aoqi@0:     // Compute the exceptional successors and types for this Block.
aoqi@0:     void compute_exceptions();
aoqi@0: 
aoqi@0:   public:
aoqi@0:     // constructors
aoqi@0:     Block(ciTypeFlow* outer, ciBlock* ciblk, JsrSet* jsrs);
aoqi@0: 
aoqi@0:     void set_trap(int trap_bci, int trap_index) {
aoqi@0:       _trap_bci = trap_bci;
aoqi@0:       _trap_index = trap_index;
aoqi@0:       assert(has_trap(), "");
aoqi@0:     }
aoqi@0:     bool has_trap()   const  { return _trap_bci != -1; }
aoqi@0:     int  trap_bci()   const  { assert(has_trap(), ""); return _trap_bci; }
aoqi@0:     int  trap_index() const  { assert(has_trap(), ""); return _trap_index; }
aoqi@0: 
aoqi@0:     // accessors
aoqi@0:     ciTypeFlow* outer() const { return state()->outer(); }
aoqi@0:     int start() const         { return _ciblock->start_bci(); }
aoqi@0:     int limit() const         { return _ciblock->limit_bci(); }
aoqi@0:     int control() const       { return _ciblock->control_bci(); }
aoqi@0:     JsrSet* jsrs() const      { return _jsrs; }
aoqi@0: 
aoqi@0:     bool    is_backedge_copy() const       { return _backedge_copy; }
aoqi@0:     void   set_backedge_copy(bool z);
aoqi@0:     int        backedge_copy_count() const { return outer()->backedge_copy_count(ciblock()->index(), _jsrs); }
aoqi@0: 
aoqi@0:     // access to entry state
aoqi@0:     int     stack_size() const         { return _state->stack_size(); }
aoqi@0:     int     monitor_count() const      { return _state->monitor_count(); }
aoqi@0:     ciType* local_type_at(int i) const { return _state->local_type_at(i); }
aoqi@0:     ciType* stack_type_at(int i) const { return _state->stack_type_at(i); }
aoqi@0: 
aoqi@0:     // Data flow on locals
aoqi@0:     bool is_invariant_local(uint v) const {
aoqi@0:       assert(is_loop_head(), "only loop heads");
aoqi@0:       // Find outermost loop with same loop head
aoqi@0:       Loop* lp = loop();
aoqi@0:       while (lp->parent() != NULL) {
aoqi@0:         if (lp->parent()->head() != lp->head()) break;
aoqi@0:         lp = lp->parent();
aoqi@0:       }
aoqi@0:       return !lp->def_locals()->test(v);
aoqi@0:     }
aoqi@0:     LocalSet* def_locals() { return _state->def_locals(); }
aoqi@0:     const LocalSet* def_locals() const { return _state->def_locals(); }
aoqi@0: 
aoqi@0:     // Get the successors for this Block.
aoqi@0:     GrowableArray<Block*>* successors(ciBytecodeStream* str,
aoqi@0:                                       StateVector* state,
aoqi@0:                                       JsrSet* jsrs);
aoqi@0:     GrowableArray<Block*>* successors() {
aoqi@0:       assert(_successors != NULL, "must be filled in");
aoqi@0:       return _successors;
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Get the exceptional successors for this Block.
aoqi@0:     GrowableArray<Block*>* exceptions() {
aoqi@0:       if (_exceptions == NULL) {
aoqi@0:         compute_exceptions();
aoqi@0:       }
aoqi@0:       return _exceptions;
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Get the exception klasses corresponding to the
aoqi@0:     // exceptional successors for this Block.
aoqi@0:     GrowableArray<ciInstanceKlass*>* exc_klasses() {
aoqi@0:       if (_exc_klasses == NULL) {
aoqi@0:         compute_exceptions();
aoqi@0:       }
aoqi@0:       return _exc_klasses;
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Is this Block compatible with a given JsrSet?
aoqi@0:     bool is_compatible_with(JsrSet* other) {
aoqi@0:       return _jsrs->is_compatible_with(other);
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Copy the value of our state vector into another.
aoqi@0:     void copy_state_into(StateVector* copy) const {
aoqi@0:       _state->copy_into(copy);
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Copy the value of our JsrSet into another
aoqi@0:     void copy_jsrs_into(JsrSet* copy) const {
aoqi@0:       _jsrs->copy_into(copy);
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Meets the start state of this block with another state, destructively
aoqi@0:     // modifying this one.  Returns true if any modification takes place.
aoqi@0:     bool meet(const StateVector* incoming) {
aoqi@0:       return state()->meet(incoming);
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Ditto, except that the incoming state is coming from an
aoqi@0:     // exception path.  This means the stack is replaced by the
aoqi@0:     // appropriate exception type.
aoqi@0:     bool meet_exception(ciInstanceKlass* exc, const StateVector* incoming) {
aoqi@0:       return state()->meet_exception(exc, incoming);
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Work list manipulation
aoqi@0:     void   set_next(Block* block) { _next = block; }
aoqi@0:     Block* next() const           { return _next; }
aoqi@0: 
aoqi@0:     void   set_on_work_list(bool c) { _on_work_list = c; }
aoqi@0:     bool   is_on_work_list() const  { return _on_work_list; }
aoqi@0: 
aoqi@0:     bool   has_pre_order() const  { return _pre_order >= 0; }
aoqi@0:     void   set_pre_order(int po)  { assert(!has_pre_order(), ""); _pre_order = po; }
aoqi@0:     int    pre_order() const      { assert(has_pre_order(), ""); return _pre_order; }
aoqi@0:     void   set_next_pre_order()   { set_pre_order(outer()->inc_next_pre_order()); }
aoqi@0:     bool   is_start() const       { return _pre_order == outer()->start_block_num(); }
aoqi@0: 
aoqi@0:     // Reverse post order
aoqi@0:     void   df_init();
aoqi@0:     bool   has_post_order() const { return _post_order >= 0; }
aoqi@0:     void   set_post_order(int po) { assert(!has_post_order() && po >= 0, ""); _post_order = po; }
aoqi@0:     void   reset_post_order(int o){ _post_order = o; }
aoqi@0:     int    post_order() const     { assert(has_post_order(), ""); return _post_order; }
aoqi@0: 
aoqi@0:     bool   has_rpo() const        { return has_post_order() && outer()->have_block_count(); }
aoqi@0:     int    rpo() const            { assert(has_rpo(), ""); return outer()->block_count() - post_order() - 1; }
aoqi@0:     void   set_rpo_next(Block* b) { _rpo_next = b; }
aoqi@0:     Block* rpo_next()             { return _rpo_next; }
aoqi@0: 
aoqi@0:     // Loops
aoqi@0:     Loop*  loop() const                  { return _loop; }
aoqi@0:     void   set_loop(Loop* lp)            { _loop = lp; }
aoqi@0:     bool   is_loop_head() const          { return _loop && _loop->head() == this; }
aoqi@0:     void   set_irreducible_entry(bool c) { _irreducible_entry = c; }
aoqi@0:     bool   is_irreducible_entry() const  { return _irreducible_entry; }
aoqi@0:     void   set_has_monitorenter()        { _has_monitorenter = true; }
aoqi@0:     bool   has_monitorenter() const      { return _has_monitorenter; }
aoqi@0:     bool   is_visited() const            { return has_pre_order(); }
aoqi@0:     bool   is_post_visited() const       { return has_post_order(); }
aoqi@0:     bool   is_clonable_exit(Loop* lp);
aoqi@0:     Block* looping_succ(Loop* lp);       // Successor inside of loop
aoqi@0:     bool   is_single_entry_loop_head() const {
aoqi@0:       if (!is_loop_head()) return false;
aoqi@0:       for (Loop* lp = loop(); lp != NULL && lp->head() == this; lp = lp->parent())
aoqi@0:         if (lp->is_irreducible()) return false;
aoqi@0:       return true;
aoqi@0:     }
aoqi@0: 
aoqi@0:     void   print_value_on(outputStream* st) const PRODUCT_RETURN;
aoqi@0:     void   print_on(outputStream* st) const       PRODUCT_RETURN;
aoqi@0:   };
aoqi@0: 
aoqi@0:   // Loop
aoqi@0:   class Loop : public ResourceObj {
aoqi@0:   private:
aoqi@0:     Loop* _parent;
aoqi@0:     Loop* _sibling;  // List of siblings, null terminated
aoqi@0:     Loop* _child;    // Head of child list threaded thru sibling pointer
aoqi@0:     Block* _head;    // Head of loop
aoqi@0:     Block* _tail;    // Tail of loop
aoqi@0:     bool   _irreducible;
aoqi@0:     LocalSet _def_locals;
aoqi@0: 
aoqi@0:   public:
aoqi@0:     Loop(Block* head, Block* tail) :
aoqi@0:       _head(head),   _tail(tail),
aoqi@0:       _parent(NULL), _sibling(NULL), _child(NULL),
aoqi@0:       _irreducible(false), _def_locals() {}
aoqi@0: 
aoqi@0:     Loop* parent()  const { return _parent; }
aoqi@0:     Loop* sibling() const { return _sibling; }
aoqi@0:     Loop* child()   const { return _child; }
aoqi@0:     Block* head()   const { return _head; }
aoqi@0:     Block* tail()   const { return _tail; }
aoqi@0:     void set_parent(Loop* p)  { _parent = p; }
aoqi@0:     void set_sibling(Loop* s) { _sibling = s; }
aoqi@0:     void set_child(Loop* c)   { _child = c; }
aoqi@0:     void set_head(Block* hd)  { _head = hd; }
aoqi@0:     void set_tail(Block* tl)  { _tail = tl; }
aoqi@0: 
aoqi@0:     int depth() const;              // nesting depth
aoqi@0: 
aoqi@0:     // Returns true if lp is a nested loop or us.
aoqi@0:     bool contains(Loop* lp) const;
aoqi@0:     bool contains(Block* blk) const { return contains(blk->loop()); }
aoqi@0: 
aoqi@0:     // Data flow on locals
aoqi@0:     LocalSet* def_locals() { return &_def_locals; }
aoqi@0:     const LocalSet* def_locals() const { return &_def_locals; }
aoqi@0: 
aoqi@0:     // Merge the branch lp into this branch, sorting on the loop head
aoqi@0:     // pre_orders. Returns the new branch.
aoqi@0:     Loop* sorted_merge(Loop* lp);
aoqi@0: 
aoqi@0:     // Mark non-single entry to loop
aoqi@0:     void set_irreducible(Block* entry) {
aoqi@0:       _irreducible = true;
aoqi@0:       entry->set_irreducible_entry(true);
aoqi@0:     }
aoqi@0:     bool is_irreducible() const { return _irreducible; }
aoqi@0: 
aoqi@0:     bool is_root() const { return _tail->pre_order() == max_jint; }
aoqi@0: 
aoqi@0:     void print(outputStream* st = tty, int indent = 0) const PRODUCT_RETURN;
aoqi@0:   };
aoqi@0: 
aoqi@0:   // Postorder iteration over the loop tree.
aoqi@0:   class PostorderLoops : public StackObj {
aoqi@0:   private:
aoqi@0:     Loop* _root;
aoqi@0:     Loop* _current;
aoqi@0:   public:
aoqi@0:     PostorderLoops(Loop* root) : _root(root), _current(root) {
aoqi@0:       while (_current->child() != NULL) {
aoqi@0:         _current = _current->child();
aoqi@0:       }
aoqi@0:     }
aoqi@0:     bool done() { return _current == NULL; }  // Finished iterating?
aoqi@0:     void next();                            // Advance to next loop
aoqi@0:     Loop* current() { return _current; }      // Return current loop.
aoqi@0:   };
aoqi@0: 
aoqi@0:   // Preorder iteration over the loop tree.
aoqi@0:   class PreorderLoops : public StackObj {
aoqi@0:   private:
aoqi@0:     Loop* _root;
aoqi@0:     Loop* _current;
aoqi@0:   public:
aoqi@0:     PreorderLoops(Loop* root) : _root(root), _current(root) {}
aoqi@0:     bool done() { return _current == NULL; }  // Finished iterating?
aoqi@0:     void next();                            // Advance to next loop
aoqi@0:     Loop* current() { return _current; }      // Return current loop.
aoqi@0:   };
aoqi@0: 
aoqi@0:   // Standard indexes of successors, for various bytecodes.
aoqi@0:   enum {
aoqi@0:     FALL_THROUGH   = 0,  // normal control
aoqi@0:     IF_NOT_TAKEN   = 0,  // the not-taken branch of an if (i.e., fall-through)
aoqi@0:     IF_TAKEN       = 1,  // the taken branch of an if
aoqi@0:     GOTO_TARGET    = 0,  // unique successor for goto, jsr, or ret
aoqi@0:     SWITCH_DEFAULT = 0,  // default branch of a switch
aoqi@0:     SWITCH_CASES   = 1   // first index for any non-default switch branches
aoqi@0:     // Unlike in other blocks, the successors of a switch are listed uniquely.
aoqi@0:   };
aoqi@0: 
aoqi@0: private:
aoqi@0:   // A mapping from pre_order to Blocks.  This array is created
aoqi@0:   // only at the end of the flow.
aoqi@0:   Block** _block_map;
aoqi@0: 
aoqi@0:   // For each ciBlock index, a list of Blocks which share this ciBlock.
aoqi@0:   GrowableArray<Block*>** _idx_to_blocklist;
aoqi@0:   // count of ciBlocks
aoqi@0:   int _ciblock_count;
aoqi@0: 
aoqi@0:   // Tells if a given instruction is able to generate an exception edge.
aoqi@0:   bool can_trap(ciBytecodeStream& str);
aoqi@0: 
aoqi@0:   // Clone the loop heads. Returns true if any cloning occurred.
aoqi@0:   bool clone_loop_heads(Loop* lp, StateVector* temp_vector, JsrSet* temp_set);
aoqi@0: 
aoqi@0:   // Clone lp's head and replace tail's successors with clone.
aoqi@0:   Block* clone_loop_head(Loop* lp, StateVector* temp_vector, JsrSet* temp_set);
aoqi@0: 
aoqi@0: public:
aoqi@0:   // Return the block beginning at bci which has a JsrSet compatible
aoqi@0:   // with jsrs.
aoqi@0:   Block* block_at(int bci, JsrSet* set, CreateOption option = create_public_copy);
aoqi@0: 
aoqi@0:   // block factory
aoqi@0:   Block* get_block_for(int ciBlockIndex, JsrSet* jsrs, CreateOption option = create_public_copy);
aoqi@0: 
aoqi@0:   // How many of the blocks have the backedge_copy bit set?
aoqi@0:   int backedge_copy_count(int ciBlockIndex, JsrSet* jsrs) const;
aoqi@0: 
aoqi@0:   // Return an existing block containing bci which has a JsrSet compatible
aoqi@0:   // with jsrs, or NULL if there is none.
aoqi@0:   Block* existing_block_at(int bci, JsrSet* set) { return block_at(bci, set, no_create); }
aoqi@0: 
aoqi@0:   // Tell whether the flow analysis has encountered an error of some sort.
aoqi@0:   bool failing() { return env()->failing() || _failure_reason != NULL; }
aoqi@0: 
aoqi@0:   // Reason this compilation is failing, such as "too many basic blocks".
aoqi@0:   const char* failure_reason() { return _failure_reason; }
aoqi@0: 
aoqi@0:   // Note a failure.
aoqi@0:   void record_failure(const char* reason);
aoqi@0: 
aoqi@0:   // Return the block of a given pre-order number.
aoqi@0:   int have_block_count() const      { return _block_map != NULL; }
aoqi@0:   int block_count() const           { assert(have_block_count(), "");
aoqi@0:                                       return _next_pre_order; }
aoqi@0:   Block* pre_order_at(int po) const { assert(0 <= po && po < block_count(), "out of bounds");
aoqi@0:                                       return _block_map[po]; }
aoqi@0:   Block* start_block() const        { return pre_order_at(start_block_num()); }
aoqi@0:   int start_block_num() const       { return 0; }
aoqi@0:   Block* rpo_at(int rpo) const      { assert(0 <= rpo && rpo < block_count(), "out of bounds");
aoqi@0:                                       return _block_map[rpo]; }
aoqi@0:   int next_pre_order()              { return _next_pre_order; }
aoqi@0:   int inc_next_pre_order()          { return _next_pre_order++; }
aoqi@0: 
aoqi@0: private:
aoqi@0:   // A work list used during flow analysis.
aoqi@0:   Block* _work_list;
aoqi@0: 
aoqi@0:   // List of blocks in reverse post order
aoqi@0:   Block* _rpo_list;
aoqi@0: 
aoqi@0:   // Next Block::_pre_order.  After mapping, doubles as block_count.
aoqi@0:   int _next_pre_order;
aoqi@0: 
aoqi@0:   // Are there more blocks on the work list?
aoqi@0:   bool work_list_empty() { return _work_list == NULL; }
aoqi@0: 
aoqi@0:   // Get the next basic block from our work list.
aoqi@0:   Block* work_list_next();
aoqi@0: 
aoqi@0:   // Add a basic block to our work list.
aoqi@0:   void add_to_work_list(Block* block);
aoqi@0: 
aoqi@0:   // Prepend a basic block to rpo list.
aoqi@0:   void prepend_to_rpo_list(Block* blk) {
aoqi@0:     blk->set_rpo_next(_rpo_list);
aoqi@0:     _rpo_list = blk;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Root of the loop tree
aoqi@0:   Loop* _loop_tree_root;
aoqi@0: 
aoqi@0:   // State used for make_jsr_record
aoqi@0:   int _jsr_count;
aoqi@0:   GrowableArray<JsrRecord*>* _jsr_records;
aoqi@0: 
aoqi@0: public:
aoqi@0:   // Make a JsrRecord for a given (entry, return) pair, if such a record
aoqi@0:   // does not already exist.
aoqi@0:   JsrRecord* make_jsr_record(int entry_address, int return_address);
aoqi@0: 
aoqi@0:   void  set_loop_tree_root(Loop* ltr) { _loop_tree_root = ltr; }
aoqi@0:   Loop* loop_tree_root()              { return _loop_tree_root; }
aoqi@0: 
aoqi@0: private:
aoqi@0:   // Get the initial state for start_bci:
aoqi@0:   const StateVector* get_start_state();
aoqi@0: 
aoqi@0:   // Merge the current state into all exceptional successors at the
aoqi@0:   // current point in the code.
aoqi@0:   void flow_exceptions(GrowableArray<Block*>* exceptions,
aoqi@0:                        GrowableArray<ciInstanceKlass*>* exc_klasses,
aoqi@0:                        StateVector* state);
aoqi@0: 
aoqi@0:   // Merge the current state into all successors at the current point
aoqi@0:   // in the code.
aoqi@0:   void flow_successors(GrowableArray<Block*>* successors,
aoqi@0:                        StateVector* state);
aoqi@0: 
aoqi@0:   // Interpret the effects of the bytecodes on the incoming state
aoqi@0:   // vector of a basic block.  Push the changed state to succeeding
aoqi@0:   // basic blocks.
aoqi@0:   void flow_block(Block* block,
aoqi@0:                   StateVector* scratch_state,
aoqi@0:                   JsrSet* scratch_jsrs);
aoqi@0: 
aoqi@0:   // Perform the type flow analysis, creating and cloning Blocks as
aoqi@0:   // necessary.
aoqi@0:   void flow_types();
aoqi@0: 
aoqi@0:   // Perform the depth first type flow analysis. Helper for flow_types.
aoqi@0:   void df_flow_types(Block* start,
aoqi@0:                      bool do_flow,
aoqi@0:                      StateVector* temp_vector,
aoqi@0:                      JsrSet* temp_set);
aoqi@0: 
aoqi@0:   // Incrementally build loop tree.
aoqi@0:   void build_loop_tree(Block* blk);
aoqi@0: 
aoqi@0:   // Create the block map, which indexes blocks in pre_order.
aoqi@0:   void map_blocks();
aoqi@0: 
aoqi@0: public:
aoqi@0:   // Perform type inference flow analysis.
aoqi@0:   void do_flow();
aoqi@0: 
aoqi@0:   void print_on(outputStream* st) const PRODUCT_RETURN;
aoqi@0: 
aoqi@0:   void rpo_print_on(outputStream* st) const PRODUCT_RETURN;
aoqi@0: };
aoqi@0: 
aoqi@0: #endif // SHARE_VM_CI_CITYPEFLOW_HPP