1 /*
   2  * Copyright (c) 1999, 2020, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_C1_C1_IR_HPP
  26 #define SHARE_C1_C1_IR_HPP
  27 
  28 #include "c1/c1_Instruction.hpp"
  29 #include "ci/ciExceptionHandler.hpp"
  30 #include "ci/ciMethod.hpp"
  31 #include "ci/ciStreams.hpp"
  32 #include "memory/allocation.hpp"
  33 
  34 // An XHandler is a C1 internal description for an exception handler
  35 
  36 class XHandler: public CompilationResourceObj {
  37  private:
  38   ciExceptionHandler* _desc;
  39 
  40   BlockBegin*         _entry_block;  // Entry block of xhandler
  41   LIR_List*           _entry_code;   // LIR-operations that must be executed before jumping to entry_block
  42   int                 _entry_pco;    // pco where entry_code (or entry_block if no entry_code) starts
  43   int                 _phi_operand;  // For resolving of phi functions at begin of entry_block
  44   int                 _scope_count;  // for filling ExceptionRangeEntry::scope_count
  45 
  46 #ifdef ASSERT
  47   int                 _lir_op_id;    // op_id of the LIR-operation throwing to this handler
  48 #endif
  49 
  50  public:
  51   // creation
  52   XHandler(ciExceptionHandler* desc)
  53     : _desc(desc)
  54     , _entry_block(NULL)
  55     , _entry_code(NULL)
  56     , _entry_pco(-1)
  57     , _phi_operand(-1)
  58     , _scope_count(-1)
  59 #ifdef ASSERT
  60     , _lir_op_id(-1)
  61 #endif
  62   { }
  63 
  64   XHandler(XHandler* other)
  65     : _desc(other->_desc)
  66     , _entry_block(other->_entry_block)
  67     , _entry_code(other->_entry_code)
  68     , _entry_pco(other->_entry_pco)
  69     , _phi_operand(other->_phi_operand)
  70     , _scope_count(other->_scope_count)
  71 #ifdef ASSERT
  72     , _lir_op_id(other->_lir_op_id)
  73 #endif
  74   { }
  75 
  76   // accessors for data of ciExceptionHandler
  77   int  beg_bci() const                           { return _desc->start(); }
  78   int  end_bci() const                           { return _desc->limit(); }
  79   int  handler_bci() const                       { return _desc->handler_bci(); }
  80   bool is_catch_all() const                      { return _desc->is_catch_all(); }
  81   int  catch_type() const                        { return _desc->catch_klass_index(); }
  82   ciInstanceKlass* catch_klass() const           { return _desc->catch_klass(); }
  83   bool covers(int bci) const                     { return beg_bci() <= bci && bci < end_bci(); }
  84 
  85   // accessors for additional fields
  86   BlockBegin* entry_block() const                { return _entry_block; }
  87   LIR_List*   entry_code() const                 { return _entry_code; }
  88   int         entry_pco() const                  { return _entry_pco; }
  89   int         phi_operand() const                { assert(_phi_operand != -1, "not set"); return _phi_operand; }
  90   int         scope_count() const                { assert(_scope_count != -1, "not set"); return _scope_count; }
  91   DEBUG_ONLY(int lir_op_id() const               { return _lir_op_id; });
  92 
  93   void set_entry_block(BlockBegin* entry_block) {
  94     assert(entry_block->is_set(BlockBegin::exception_entry_flag), "must be an exception handler entry");
  95     assert(entry_block->bci() == handler_bci(), "bci's must correspond");
  96     _entry_block = entry_block;
  97   }
  98   void set_entry_code(LIR_List* entry_code)      { _entry_code = entry_code; }
  99   void set_entry_pco(int entry_pco)              { _entry_pco = entry_pco; }
 100   void set_phi_operand(int phi_operand)          { _phi_operand = phi_operand; }
 101   void set_scope_count(int scope_count)          { _scope_count = scope_count; }
 102   DEBUG_ONLY(void set_lir_op_id(int lir_op_id)   { _lir_op_id = lir_op_id; });
 103 
 104   bool equals(XHandler* other) const;
 105 };
 106 
 107 typedef GrowableArray<XHandler*> _XHandlerList;
 108 
 109 // XHandlers is the C1 internal list of exception handlers for a method
 110 class XHandlers: public CompilationResourceObj {
 111  private:
 112   _XHandlerList    _list;
 113 
 114  public:
 115   // creation
 116   XHandlers() : _list()                          { }
 117   XHandlers(ciMethod* method);
 118   XHandlers(XHandlers* other);
 119 
 120   // accessors
 121   int       length() const                       { return _list.length(); }
 122   XHandler* handler_at(int i) const              { return _list.at(i); }
 123   bool      has_handlers() const                 { return _list.length() > 0; }
 124   void      append(XHandler* h)                  { _list.append(h); }
 125   XHandler* remove_last()                        { return _list.pop(); }
 126 
 127   bool      could_catch(ciInstanceKlass* klass, bool type_is_exact) const;
 128   bool      equals(XHandlers* others) const;
 129 };
 130 
 131 
 132 class IRScope;
 133 typedef GrowableArray<IRScope*> IRScopeList;
 134 
 135 class Compilation;
 136 class IRScope: public CompilationResourceObj {
 137  private:
 138   // hierarchy
 139   Compilation*  _compilation;                    // the current compilation
 140   IRScope*      _caller;                         // the caller scope, or NULL
 141   int           _level;                          // the inlining level
 142   ciMethod*     _method;                         // the corresponding method
 143   IRScopeList   _callees;                        // the inlined method scopes
 144 
 145   // graph
 146   XHandlers*    _xhandlers;                      // the exception handlers
 147   int           _number_of_locks;                // the number of monitor lock slots needed
 148   bool          _monitor_pairing_ok;             // the monitor pairing info
 149   bool          _wrote_final;                    // has written final field
 150   bool          _wrote_fields;                   // has written fields
 151   bool          _wrote_volatile;                 // has written volatile field
 152   BlockBegin*   _start;                          // the start block, successsors are method entries
 153 
 154   ResourceBitMap _requires_phi_function;         // bit is set if phi functions at loop headers are necessary for a local variable
 155 
 156   // helper functions
 157   BlockBegin* build_graph(Compilation* compilation, int osr_bci);
 158 
 159  public:
 160   // creation
 161   IRScope(Compilation* compilation, IRScope* caller, int caller_bci, ciMethod* method, int osr_bci, bool create_graph = false);
 162 
 163   // accessors
 164   Compilation*  compilation() const              { return _compilation; }
 165   IRScope*      caller() const                   { return _caller; }
 166   int           level() const                    { return _level; }
 167   ciMethod*     method() const                   { return _method; }
 168   int           max_stack() const;               // NOTE: expensive
 169   BitMap&       requires_phi_function()          { return _requires_phi_function; }
 170 
 171   // hierarchy
 172   bool          is_top_scope() const             { return _caller == NULL; }
 173   void          add_callee(IRScope* callee)      { _callees.append(callee); }
 174   int           number_of_callees() const        { return _callees.length(); }
 175   IRScope*      callee_no(int i) const           { return _callees.at(i); }
 176 
 177   // accessors, graph
 178   bool          is_valid() const                 { return start() != NULL; }
 179   XHandlers*    xhandlers() const                { return _xhandlers; }
 180   int           number_of_locks() const          { return _number_of_locks; }
 181   void          set_min_number_of_locks(int n)   { if (n > _number_of_locks) _number_of_locks = n; }
 182   bool          monitor_pairing_ok() const       { return _monitor_pairing_ok; }
 183   BlockBegin*   start() const                    { return _start; }
 184   void          set_wrote_final()                { _wrote_final = true; }
 185   bool          wrote_final    () const          { return _wrote_final; }
 186   void          set_wrote_fields()               { _wrote_fields = true; }
 187   bool          wrote_fields    () const         { return _wrote_fields; }
 188   void          set_wrote_volatile()             { _wrote_volatile = true; }
 189   bool          wrote_volatile    () const       { return _wrote_volatile; }
 190 };
 191 
 192 
 193 //
 194 // IRScopeDebugInfo records the debug information for a particular IRScope
 195 // in a particular CodeEmitInfo.  This allows the information to be computed
 196 // once early enough for the OopMap to be available to the LIR and also to be
 197 // reemited for different pcs using the same CodeEmitInfo without recomputing
 198 // everything.
 199 //
 200 
 201 class IRScopeDebugInfo: public CompilationResourceObj {
 202  private:
 203   IRScope*                      _scope;
 204   int                           _bci;
 205   GrowableArray<ScopeValue*>*   _locals;
 206   GrowableArray<ScopeValue*>*   _expressions;
 207   GrowableArray<MonitorValue*>* _monitors;
 208   IRScopeDebugInfo*             _caller;
 209 
 210  public:
 211   IRScopeDebugInfo(IRScope*                      scope,
 212                    int                           bci,
 213                    GrowableArray<ScopeValue*>*   locals,
 214                    GrowableArray<ScopeValue*>*   expressions,
 215                    GrowableArray<MonitorValue*>* monitors,
 216                    IRScopeDebugInfo*             caller):
 217       _scope(scope)
 218     , _bci(bci)
 219     , _locals(locals)
 220     , _expressions(expressions)
 221     , _monitors(monitors)
 222     , _caller(caller) {}
 223 
 224 
 225   IRScope*                      scope()       { return _scope;       }
 226   int                           bci()         { return _bci;         }
 227   GrowableArray<ScopeValue*>*   locals()      { return _locals;      }
 228   GrowableArray<ScopeValue*>*   expressions() { return _expressions; }
 229   GrowableArray<MonitorValue*>* monitors()    { return _monitors;    }
 230   IRScopeDebugInfo*             caller()      { return _caller;      }
 231 
 232   //Whether we should reexecute this bytecode for deopt
 233   bool should_reexecute();
 234 
 235   void record_debug_info(DebugInformationRecorder* recorder, int pc_offset, bool topmost, bool is_method_handle_invoke = false) {
 236     if (caller() != NULL) {
 237       // Order is significant:  Must record caller first.
 238       caller()->record_debug_info(recorder, pc_offset, false/*topmost*/);
 239     }
 240     DebugToken* locvals = recorder->create_scope_values(locals());
 241     DebugToken* expvals = recorder->create_scope_values(expressions());
 242     DebugToken* monvals = recorder->create_monitor_values(monitors());
 243     // reexecute allowed only for the topmost frame
 244     bool reexecute = topmost ? should_reexecute() : false;
 245     bool return_oop = false; // This flag will be ignored since it used only for C2 with escape analysis.
 246     bool rethrow_exception = false;
 247     bool not_global_escape_in_scope = false;
 248     bool arg_escape = false;
 249     recorder->describe_scope(pc_offset, methodHandle(), scope()->method(), bci(),
 250                              reexecute, rethrow_exception, is_method_handle_invoke, return_oop, not_global_escape_in_scope, arg_escape,
 251                              locvals, expvals, monvals);
 252   }
 253 };
 254 
 255 
 256 class CodeEmitInfo: public CompilationResourceObj {
 257   friend class LinearScan;
 258  private:
 259   IRScopeDebugInfo* _scope_debug_info;
 260   IRScope*          _scope;
 261   XHandlers*        _exception_handlers;
 262   OopMap*           _oop_map;
 263   ValueStack*       _stack;                      // used by deoptimization (contains also monitors
 264   bool              _is_method_handle_invoke;    // true if the associated call site is a MethodHandle call site.
 265   bool              _deoptimize_on_exception;
 266 
 267   FrameMap*     frame_map() const                { return scope()->compilation()->frame_map(); }
 268   Compilation*  compilation() const              { return scope()->compilation(); }
 269 
 270  public:
 271 
 272   // use scope from ValueStack
 273   CodeEmitInfo(ValueStack* stack, XHandlers* exception_handlers, bool deoptimize_on_exception = false);
 274 
 275   // make a copy
 276   CodeEmitInfo(CodeEmitInfo* info, ValueStack* stack = NULL);
 277 
 278   // accessors
 279   OopMap* oop_map()                              { return _oop_map; }
 280   ciMethod* method() const                       { return _scope->method(); }
 281   IRScope* scope() const                         { return _scope; }
 282   XHandlers* exception_handlers() const          { return _exception_handlers; }
 283   ValueStack* stack() const                      { return _stack; }
 284   bool deoptimize_on_exception() const           { return _deoptimize_on_exception; }
 285 
 286   void add_register_oop(LIR_Opr opr);
 287   void record_debug_info(DebugInformationRecorder* recorder, int pc_offset);
 288 
 289   bool     is_method_handle_invoke() const { return _is_method_handle_invoke;     }
 290   void set_is_method_handle_invoke(bool x) {        _is_method_handle_invoke = x; }
 291 
 292   int interpreter_frame_size() const;
 293 };
 294 
 295 
 296 class IR: public CompilationResourceObj {
 297  private:
 298   Compilation*     _compilation;                 // the current compilation
 299   IRScope*         _top_scope;                   // the root of the scope hierarchy
 300   int              _num_loops;                   // Total number of loops
 301   BlockList*       _code;                        // the blocks in code generation order w/ use counts
 302 
 303  public:
 304   // creation
 305   IR(Compilation* compilation, ciMethod* method, int osr_bci);
 306 
 307   // accessors
 308   bool             is_valid() const              { return top_scope()->is_valid(); }
 309   Compilation*     compilation() const           { return _compilation; }
 310   IRScope*         top_scope() const             { return _top_scope; }
 311   int              number_of_locks() const       { return top_scope()->number_of_locks(); }
 312   ciMethod*        method() const                { return top_scope()->method(); }
 313   BlockBegin*      start() const                 { return top_scope()->start(); }
 314   BlockBegin*      std_entry() const             { return start()->end()->as_Base()->std_entry(); }
 315   BlockBegin*      osr_entry() const             { return start()->end()->as_Base()->osr_entry(); }
 316   BlockList*       code() const                  { return _code; }
 317   int              num_loops() const             { return _num_loops; }
 318   int              max_stack() const             { return top_scope()->max_stack(); } // expensive
 319 
 320   // ir manipulation
 321   void optimize_blocks();
 322   void eliminate_null_checks();
 323   void compute_predecessors();
 324   void split_critical_edges();
 325   void compute_code();
 326   void compute_use_counts();
 327 
 328   // The linear-scan order and the code emission order are equal, but
 329   // this may change in future
 330   BlockList* linear_scan_order() {  assert(_code != NULL, "not computed"); return _code; }
 331 
 332   // iteration
 333   void iterate_preorder   (BlockClosure* closure);
 334   void iterate_postorder  (BlockClosure* closure);
 335   void iterate_linear_scan_order(BlockClosure* closure);
 336 
 337   // debugging
 338   static void print(BlockBegin* start, bool cfg_only, bool live_only = false) PRODUCT_RETURN;
 339   void print(bool cfg_only, bool live_only = false)                           PRODUCT_RETURN;
 340   void verify()                                                               PRODUCT_RETURN;
 341 };
 342 
 343 
 344 // Globally do instruction substitution and remove substituted
 345 // instructions from the instruction list.
 346 //
 347 
 348 class SubstitutionResolver: public BlockClosure, ValueVisitor {
 349   virtual void visit(Value* v);
 350 
 351  public:
 352   SubstitutionResolver(IR* hir) {
 353     hir->iterate_preorder(this);
 354   }
 355 
 356   SubstitutionResolver(BlockBegin* block) {
 357     block->iterate_preorder(this);
 358   }
 359 
 360   virtual void block_do(BlockBegin* block);
 361 };
 362 
 363 #endif // SHARE_C1_C1_IR_HPP