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   bool                          _should_reexecute;
210 
211  public:
212   IRScopeDebugInfo(IRScope*                      scope,
213                    int                           bci,
214                    GrowableArray<ScopeValue*>*   locals,
215                    GrowableArray<ScopeValue*>*   expressions,
216                    GrowableArray<MonitorValue*>* monitors,
217                    IRScopeDebugInfo*             caller,
218                    bool                          should_reexecute):
219       _scope(scope)
220     , _bci(bci)
221     , _locals(locals)
222     , _expressions(expressions)
223     , _monitors(monitors)
224     , _caller(caller)
225     , _should_reexecute(should_reexecute) {}
226 
227 
228   IRScope*                      scope()       { return _scope;       }
229   int                           bci()         { return _bci;         }
230   GrowableArray<ScopeValue*>*   locals()      { return _locals;      }
231   GrowableArray<ScopeValue*>*   expressions() { return _expressions; }
232   GrowableArray<MonitorValue*>* monitors()    { return _monitors;    }
233   IRScopeDebugInfo*             caller()      { return _caller;      }
234 
235   //Whether we should reexecute this bytecode for deopt
236   bool should_reexecute();
237 
238   void record_debug_info(DebugInformationRecorder* recorder, int pc_offset, bool topmost, bool is_method_handle_invoke = false, bool maybe_return_as_fields = false) {
239     if (caller() != NULL) {
240       // Order is significant:  Must record caller first.
241       caller()->record_debug_info(recorder, pc_offset, false/*topmost*/);
242     }
243     DebugToken* locvals = recorder->create_scope_values(locals());
244     DebugToken* expvals = recorder->create_scope_values(expressions());
245     DebugToken* monvals = recorder->create_monitor_values(monitors());
246     // reexecute allowed only for the topmost frame
247     bool reexecute = topmost ? should_reexecute() : false;
248     bool return_oop = false;
249     bool return_scalarized = false;
250     if (maybe_return_as_fields) {
251       return_oop = true;
252       return_scalarized = true;
253     }
254     bool rethrow_exception = false;
255     bool is_opt_native = false;
256     bool has_ea_local_in_scope = false;
257     bool arg_escape = false;
258     recorder->describe_scope(pc_offset, methodHandle(), scope()->method(), bci(),
259                              reexecute, rethrow_exception, is_method_handle_invoke, is_opt_native, return_oop, return_scalarized,
260                              has_ea_local_in_scope, arg_escape, locvals, expvals, monvals);
261   }
262 };
263 
264 
265 class CodeEmitInfo: public CompilationResourceObj {
266   friend class LinearScan;
267  private:
268   IRScopeDebugInfo* _scope_debug_info;
269   IRScope*          _scope;
270   XHandlers*        _exception_handlers;
271   OopMap*           _oop_map;
272   ValueStack*       _stack;                      // used by deoptimization (contains also monitors
273   bool              _is_method_handle_invoke;    // true if the associated call site is a MethodHandle call site.
274   bool              _deoptimize_on_exception;
275 
276   FrameMap*     frame_map() const                { return scope()->compilation()->frame_map(); }
277   Compilation*  compilation() const              { return scope()->compilation(); }
278 
279  public:
280 
281   // use scope from ValueStack
282   CodeEmitInfo(ValueStack* stack, XHandlers* exception_handlers, bool deoptimize_on_exception = false);
283 
284   // make a copy
285   CodeEmitInfo(CodeEmitInfo* info, ValueStack* stack = NULL);
286 
287   // accessors
288   OopMap* oop_map()                              { return _oop_map; }
289   ciMethod* method() const                       { return _scope->method(); }
290   IRScope* scope() const                         { return _scope; }
291   XHandlers* exception_handlers() const          { return _exception_handlers; }
292   ValueStack* stack() const                      { return _stack; }
293   bool deoptimize_on_exception() const           { return _deoptimize_on_exception; }
294 
295   void add_register_oop(LIR_Opr opr);
296   void record_debug_info(DebugInformationRecorder* recorder, int pc_offset, bool maybe_return_as_fields = false);
297 
298   bool     is_method_handle_invoke() const { return _is_method_handle_invoke;     }
299   void set_is_method_handle_invoke(bool x) {        _is_method_handle_invoke = x; }
300 
301   int interpreter_frame_size() const;
302 };
303 
304 
305 class IR: public CompilationResourceObj {
306  private:
307   Compilation*     _compilation;                 // the current compilation
308   IRScope*         _top_scope;                   // the root of the scope hierarchy
309   int              _num_loops;                   // Total number of loops
310   BlockList*       _code;                        // the blocks in code generation order w/ use counts
311 
312  public:
313   // creation
314   IR(Compilation* compilation, ciMethod* method, int osr_bci);
315 
316   // accessors
317   bool             is_valid() const              { return top_scope()->is_valid(); }
318   Compilation*     compilation() const           { return _compilation; }
319   IRScope*         top_scope() const             { return _top_scope; }
320   int              number_of_locks() const       { return top_scope()->number_of_locks(); }
321   ciMethod*        method() const                { return top_scope()->method(); }
322   BlockBegin*      start() const                 { return top_scope()->start(); }
323   BlockBegin*      std_entry() const             { return start()->end()->as_Base()->std_entry(); }
324   BlockBegin*      osr_entry() const             { return start()->end()->as_Base()->osr_entry(); }
325   BlockList*       code() const                  { return _code; }
326   int              num_loops() const             { return _num_loops; }
327   int              max_stack() const             { return top_scope()->max_stack(); } // expensive
328 
329   // ir manipulation
330   void optimize_blocks();
331   void eliminate_null_checks();
332   void compute_predecessors();
333   void split_critical_edges();
334   void compute_code();
335   void compute_use_counts();
336 
337   // The linear-scan order and the code emission order are equal, but
338   // this may change in future
339   BlockList* linear_scan_order() {  assert(_code != NULL, "not computed"); return _code; }
340 
341   // iteration
342   void iterate_preorder   (BlockClosure* closure);
343   void iterate_postorder  (BlockClosure* closure);
344   void iterate_linear_scan_order(BlockClosure* closure);
345 
346   // debugging
347   static void print(BlockBegin* start, bool cfg_only, bool live_only = false) PRODUCT_RETURN;
348   void print(bool cfg_only, bool live_only = false)                           PRODUCT_RETURN;
349   void verify()                                                               PRODUCT_RETURN;
350 };
351 
352 
353 // Globally do instruction substitution and remove substituted
354 // instructions from the instruction list.
355 //
356 
357 class SubstitutionResolver: public BlockClosure, ValueVisitor {
358   virtual void visit(Value* v);
359 
360  public:
361   SubstitutionResolver(IR* hir) {
362     hir->iterate_preorder(this);
363   }
364 
365   SubstitutionResolver(BlockBegin* block) {
366     block->iterate_preorder(this);
367   }
368 
369   virtual void block_do(BlockBegin* block);
370 };
371 
372 #endif // SHARE_C1_C1_IR_HPP