1 /*
  2  * Copyright (c) 1999, 2023, 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.
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 24 
 25 #ifndef SHARE_C1_C1_GRAPHBUILDER_HPP
 26 #define SHARE_C1_C1_GRAPHBUILDER_HPP
 27 
 28 #include "c1/c1_IR.hpp"
 29 #include "c1/c1_Instruction.hpp"
 30 #include "c1/c1_ValueMap.hpp"
 31 #include "c1/c1_ValueStack.hpp"
 32 #include "ci/ciMethodData.hpp"
 33 #include "ci/ciStreams.hpp"
 34 #include "compiler/compileLog.hpp"
 35 
 36 class MemoryBuffer;
 37 
 38 class GraphBuilder {
 39   friend class JfrResolution;
 40  private:
 41   // Per-scope data. These are pushed and popped as we descend into
 42   // inlined methods. Currently in order to generate good code in the
 43   // inliner we have to attempt to inline methods directly into the
 44   // basic block we are parsing; this adds complexity.
 45   class ScopeData: public CompilationResourceObj {
 46    private:
 47     ScopeData*  _parent;
 48     // bci-to-block mapping
 49     BlockList*   _bci2block;
 50     // Scope
 51     IRScope*     _scope;
 52     // Whether this scope or any parent scope has exception handlers
 53     bool         _has_handler;
 54     // The bytecodes
 55     ciBytecodeStream* _stream;
 56 
 57     // Work list
 58     BlockList*   _work_list;
 59 
 60     // Maximum inline size for this scope
 61     intx         _max_inline_size;
 62     // Expression stack depth at point where inline occurred
 63     int          _caller_stack_size;
 64 
 65     // The continuation point for the inline. Currently only used in
 66     // multi-block inlines, but eventually would like to use this for
 67     // all inlines for uniformity and simplicity; in this case would
 68     // get the continuation point from the BlockList instead of
 69     // fabricating it anew because Invokes would be considered to be
 70     // BlockEnds.
 71     BlockBegin*  _continuation;
 72 
 73     // Was this ScopeData created only for the parsing and inlining of
 74     // a jsr?
 75     bool         _parsing_jsr;
 76     // We track the destination bci of the jsr only to determine
 77     // bailout conditions, since we only handle a subset of all of the
 78     // possible jsr-ret control structures. Recursive invocations of a
 79     // jsr are disallowed by the verifier.
 80     int          _jsr_entry_bci;
 81     // We need to track the local variable in which the return address
 82     // was stored to ensure we can handle inlining the jsr, because we
 83     // don't handle arbitrary jsr/ret constructs.
 84     int          _jsr_ret_addr_local;
 85     // If we are parsing a jsr, the continuation point for rets
 86     BlockBegin*  _jsr_continuation;
 87     // Cloned XHandlers for jsr-related ScopeDatas
 88     XHandlers*   _jsr_xhandlers;
 89 
 90     // Number of returns seen in this scope
 91     int          _num_returns;
 92 
 93     // In order to generate profitable code for inlining, we currently
 94     // have to perform an optimization for single-block inlined
 95     // methods where we continue parsing into the same block. This
 96     // allows us to perform CSE across inlined scopes and to avoid
 97     // storing parameters to the stack. Having a global register
 98     // allocator and being able to perform global CSE would allow this
 99     // code to be removed and thereby simplify the inliner.
100     BlockBegin*  _cleanup_block;       // The block to which the return was added
101     Instruction* _cleanup_return_prev; // Instruction before return instruction
102     ValueStack*  _cleanup_state;       // State of that block (not yet pinned)
103 
104     // When inlining do not push the result on the stack
105     bool         _ignore_return;
106 
107    public:
108     ScopeData(ScopeData* parent);
109 
110     ScopeData* parent() const                      { return _parent;            }
111 
112     BlockList* bci2block() const                   { return _bci2block;         }
113     void       set_bci2block(BlockList* bci2block) { _bci2block = bci2block;    }
114 
115     // NOTE: this has a different effect when parsing jsrs
116     BlockBegin* block_at(int bci);
117 
118     IRScope* scope() const                         { return _scope;             }
119     // Has side-effect of setting has_handler flag
120     void set_scope(IRScope* scope);
121 
122     // Whether this or any parent scope has exception handlers
123     bool has_handler() const                       { return _has_handler;       }
124     void set_has_handler()                         { _has_handler = true;       }
125 
126     // Exception handlers list to be used for this scope
127     XHandlers* xhandlers() const;
128 
129     // How to get a block to be parsed
130     void add_to_work_list(BlockBegin* block);
131     // How to remove the next block to be parsed; returns null if none left
132     BlockBegin* remove_from_work_list();
133     // Indicates parse is over
134     bool is_work_list_empty() const;
135 
136     ciBytecodeStream* stream()                     { return _stream;            }
137     void set_stream(ciBytecodeStream* stream)      { _stream = stream;          }
138 
139     intx max_inline_size() const                   { return _max_inline_size;   }
140 
141     BlockBegin* continuation() const               { return _continuation;      }
142     void set_continuation(BlockBegin* cont)        { _continuation = cont;      }
143 
144     // Indicates whether this ScopeData was pushed only for the
145     // parsing and inlining of a jsr
146     bool parsing_jsr() const                       { return _parsing_jsr;       }
147     void set_parsing_jsr()                         { _parsing_jsr = true;       }
148     int  jsr_entry_bci() const                     { return _jsr_entry_bci;     }
149     void set_jsr_entry_bci(int bci)                { _jsr_entry_bci = bci;      }
150     void set_jsr_return_address_local(int local_no){ _jsr_ret_addr_local = local_no; }
151     int  jsr_return_address_local() const          { return _jsr_ret_addr_local; }
152     // Must be called after scope is set up for jsr ScopeData
153     void setup_jsr_xhandlers();
154 
155     // The jsr continuation is only used when parsing_jsr is true, and
156     // is different from the "normal" continuation since we can end up
157     // doing a return (rather than a ret) from within a subroutine
158     BlockBegin* jsr_continuation() const           { return _jsr_continuation;  }
159     void set_jsr_continuation(BlockBegin* cont)    { _jsr_continuation = cont;  }
160 
161     int num_returns();
162     void incr_num_returns();
163 
164     void set_inline_cleanup_info(BlockBegin* block,
165                                  Instruction* return_prev,
166                                  ValueStack* return_state);
167     BlockBegin*  inline_cleanup_block() const      { return _cleanup_block; }
168     Instruction* inline_cleanup_return_prev() const{ return _cleanup_return_prev; }
169     ValueStack*  inline_cleanup_state() const      { return _cleanup_state; }
170 
171     bool ignore_return() const                     { return _ignore_return;          }
172     void set_ignore_return(bool ignore_return)     { _ignore_return = ignore_return; }
173   };
174 
175   // for all GraphBuilders
176   static bool       _can_trap[Bytecodes::number_of_java_codes];
177 
178   // for each instance of GraphBuilder
179   ScopeData*        _scope_data;                 // Per-scope data; used for inlining
180   Compilation*      _compilation;                // the current compilation
181   ValueMap*         _vmap;                       // the map of values encountered (for CSE)
182   MemoryBuffer*     _memory;
183   const char*       _inline_bailout_msg;         // non-null if most recent inline attempt failed
184   int               _instruction_count;          // for bailing out in pathological jsr/ret cases
185   BlockBegin*       _start;                      // the start block
186   BlockBegin*       _osr_entry;                  // the osr entry block block
187   ValueStack*       _initial_state;              // The state for the start block
188 
189   // for each call to connect_to_end; can also be set by inliner
190   BlockBegin*       _block;                      // the current block
191   ValueStack*       _state;                      // the current execution state
192   Instruction*      _last;                       // the last instruction added
193   bool              _skip_block;                 // skip processing of the rest of this block
194 
195   // accessors
196   ScopeData*        scope_data() const           { return _scope_data; }
197   Compilation*      compilation() const          { return _compilation; }
198   BlockList*        bci2block() const            { return scope_data()->bci2block(); }
199   ValueMap*         vmap() const                 { assert(UseLocalValueNumbering, "should not access otherwise"); return _vmap; }
200   bool              has_handler() const          { return scope_data()->has_handler(); }
201 
202   BlockBegin*       block() const                { return _block; }
203   ValueStack*       state() const                { return _state; }
204   void              set_state(ValueStack* state) { _state = state; }
205   IRScope*          scope() const                { return scope_data()->scope(); }
206   ciMethod*         method() const               { return scope()->method(); }
207   ciBytecodeStream* stream() const               { return scope_data()->stream(); }
208   Instruction*      last() const                 { return _last; }
209   Bytecodes::Code   code() const                 { return stream()->cur_bc(); }
210   int               bci() const                  { return stream()->cur_bci(); }
211   int               next_bci() const             { return stream()->next_bci(); }
212 
213   // unified bailout support
214   void bailout(const char* msg) const            { compilation()->bailout(msg); }
215   bool bailed_out() const                        { return compilation()->bailed_out(); }
216 
217   // stack manipulation helpers
218   void ipush(Value t) const                      { state()->ipush(t); }
219   void lpush(Value t) const                      { state()->lpush(t); }
220   void fpush(Value t) const                      { state()->fpush(t); }
221   void dpush(Value t) const                      { state()->dpush(t); }
222   void apush(Value t) const                      { state()->apush(t); }
223   void  push(ValueType* type, Value t) const     { state()-> push(type, t); }
224 
225   Value ipop()                                   { return state()->ipop(); }
226   Value lpop()                                   { return state()->lpop(); }
227   Value fpop()                                   { return state()->fpop(); }
228   Value dpop()                                   { return state()->dpop(); }
229   Value apop()                                   { return state()->apop(); }
230   Value  pop(ValueType* type)                    { return state()-> pop(type); }
231 
232   // instruction helpers
233   void load_constant();
234   void load_local(ValueType* type, int index);
235   void store_local(ValueType* type, int index);
236   void store_local(ValueStack* state, Value value, int index);
237   void load_indexed (BasicType type);
238   void store_indexed(BasicType type);
239   void stack_op(Bytecodes::Code code);
240   void arithmetic_op(ValueType* type, Bytecodes::Code code, ValueStack* state_before = nullptr);
241   void negate_op(ValueType* type);
242   void shift_op(ValueType* type, Bytecodes::Code code);
243   void logic_op(ValueType* type, Bytecodes::Code code);
244   void compare_op(ValueType* type, Bytecodes::Code code);
245   void convert(Bytecodes::Code op, BasicType from, BasicType to);
246   void increment();
247   void _goto(int from_bci, int to_bci);
248   void if_node(Value x, If::Condition cond, Value y, ValueStack* stack_before);
249   void if_zero(ValueType* type, If::Condition cond);
250   void if_null(ValueType* type, If::Condition cond);
251   void if_same(ValueType* type, If::Condition cond);
252   void jsr(int dest);
253   void ret(int local_index);
254   void table_switch();
255   void lookup_switch();
256   void method_return(Value x, bool ignore_return = false);
257   void call_register_finalizer();
258   void access_field(Bytecodes::Code code);
259   void invoke(Bytecodes::Code code);
260   void new_instance(int klass_index);
261   void new_type_array();
262   void new_object_array();
263   void check_cast(int klass_index);
264   void instance_of(int klass_index);
265   void monitorenter(Value x, int bci);
266   void monitorexit(Value x, int bci);
267   void new_multi_array(int dimensions);
268   void throw_op(int bci);
269   Value round_fp(Value fp_value);
270 
271   // stack/code manipulation helpers
272   Instruction* append_with_bci(Instruction* instr, int bci);
273   Instruction* append(Instruction* instr);
274   Instruction* append_split(StateSplit* instr);
275 
276   // other helpers
277   BlockBegin* block_at(int bci)                  { return scope_data()->block_at(bci); }
278   XHandlers* handle_exception(Instruction* instruction);
279   void connect_to_end(BlockBegin* beg);
280   void null_check(Value value);
281   void eliminate_redundant_phis(BlockBegin* start);
282   BlockEnd* iterate_bytecodes_for_block(int bci);
283   void iterate_all_blocks(bool start_in_current_block_for_inlining = false);
284   Dependencies* dependency_recorder() const; // = compilation()->dependencies()
285   bool direct_compare(ciKlass* k);
286   Value make_constant(ciConstant value, ciField* field);
287 
288   void kill_all();
289 
290   // use of state copy routines (try to minimize unnecessary state
291   // object allocations):
292 
293   // - if the instruction unconditionally needs a full copy of the
294   // state (for patching for example), then use copy_state_before*
295 
296   // - if the instruction needs a full copy of the state only for
297   // handler generation (Instruction::needs_exception_state() returns
298   // false) then use copy_state_exhandling*
299 
300   // - if the instruction needs either a full copy of the state for
301   // handler generation and a least a minimal copy of the state (as
302   // returned by Instruction::exception_state()) for debug info
303   // generation (that is when Instruction::needs_exception_state()
304   // returns true) then use copy_state_for_exception*
305 
306   ValueStack* copy_state_before_with_bci(int bci);
307   ValueStack* copy_state_before();
308   ValueStack* copy_state_exhandling_with_bci(int bci);
309   ValueStack* copy_state_exhandling();
310   ValueStack* copy_state_for_exception_with_bci(int bci);
311   ValueStack* copy_state_for_exception();
312   ValueStack* copy_state_if_bb(bool is_bb) { return (is_bb || compilation()->is_optimistic()) ? copy_state_before() : nullptr; }
313   ValueStack* copy_state_indexed_access() { return compilation()->is_optimistic() ? copy_state_before() : copy_state_for_exception(); }
314 
315   //
316   // Inlining support
317   //
318 
319   // accessors
320   bool parsing_jsr() const                               { return scope_data()->parsing_jsr();           }
321   BlockBegin* continuation() const                       { return scope_data()->continuation();          }
322   BlockBegin* jsr_continuation() const                   { return scope_data()->jsr_continuation();      }
323   void set_continuation(BlockBegin* continuation)        { scope_data()->set_continuation(continuation); }
324   void set_inline_cleanup_info(BlockBegin* block,
325                                Instruction* return_prev,
326                                ValueStack* return_state) { scope_data()->set_inline_cleanup_info(block,
327                                                                                                   return_prev,
328                                                                                                   return_state); }
329   void set_inline_cleanup_info() {
330     set_inline_cleanup_info(_block, _last, _state);
331   }
332   BlockBegin*  inline_cleanup_block() const              { return scope_data()->inline_cleanup_block();  }
333   Instruction* inline_cleanup_return_prev() const        { return scope_data()->inline_cleanup_return_prev(); }
334   ValueStack*  inline_cleanup_state() const              { return scope_data()->inline_cleanup_state();  }
335   void restore_inline_cleanup_info() {
336     _block = inline_cleanup_block();
337     _last  = inline_cleanup_return_prev();
338     _state = inline_cleanup_state();
339   }
340   void incr_num_returns()                                { scope_data()->incr_num_returns();             }
341   int  num_returns() const                               { return scope_data()->num_returns();           }
342   intx max_inline_size() const                           { return scope_data()->max_inline_size();       }
343   int  inline_level() const                              { return scope()->level();                      }
344   int  recursive_inline_level(ciMethod* callee) const;
345 
346   // inlining of synchronized methods
347   void inline_sync_entry(Value lock, BlockBegin* sync_handler);
348   void fill_sync_handler(Value lock, BlockBegin* sync_handler, bool default_handler = false);
349 
350   void build_graph_for_intrinsic(ciMethod* callee, bool ignore_return);
351 
352   // inliners
353   bool try_inline(           ciMethod* callee, bool holder_known, bool ignore_return, Bytecodes::Code bc = Bytecodes::_illegal, Value receiver = nullptr);
354   bool try_inline_intrinsics(ciMethod* callee, bool ignore_return = false);
355   bool try_inline_full(      ciMethod* callee, bool holder_known, bool ignore_return, Bytecodes::Code bc = Bytecodes::_illegal, Value receiver = nullptr);
356   bool try_inline_jsr(int jsr_dest_bci);
357 
358   const char* check_can_parse(ciMethod* callee) const;
359   const char* should_not_inline(ciMethod* callee) const;
360 
361   // JSR 292 support
362   bool try_method_handle_inline(ciMethod* callee, bool ignore_return);
363 
364   // helpers
365   void inline_bailout(const char* msg);
366   BlockBegin* header_block(BlockBegin* entry, BlockBegin::Flag f, ValueStack* state);
367   BlockBegin* setup_start_block(int osr_bci, BlockBegin* std_entry, BlockBegin* osr_entry, ValueStack* init_state);
368   void setup_osr_entry_block();
369   void clear_inline_bailout();
370   ValueStack* state_at_entry();
371   void push_root_scope(IRScope* scope, BlockList* bci2block, BlockBegin* start);
372   void push_scope(ciMethod* callee, BlockBegin* continuation);
373   void push_scope_for_jsr(BlockBegin* jsr_continuation, int jsr_dest_bci);
374   void pop_scope();
375   void pop_scope_for_jsr();
376 
377   void append_unsafe_get(ciMethod* callee, BasicType t, bool is_volatile);
378   void append_unsafe_put(ciMethod* callee, BasicType t, bool is_volatile);
379   void append_unsafe_CAS(ciMethod* callee);
380   void append_unsafe_get_and_set(ciMethod* callee, bool is_add);
381   void append_char_access(ciMethod* callee, bool is_store);
382 
383   void print_inlining(ciMethod* callee, const char* msg, bool success = true);
384 
385   void profile_call(ciMethod* callee, Value recv, ciKlass* predicted_holder, Values* obj_args, bool inlined);
386   void profile_return_type(Value ret, ciMethod* callee, ciMethod* m = nullptr, int bci = -1);
387   void profile_invocation(ciMethod* inlinee, ValueStack* state);
388 
389   // Shortcuts to profiling control.
390   bool is_profiling()          { return _compilation->is_profiling();          }
391   bool profile_branches()      { return _compilation->profile_branches();      }
392   bool profile_calls()         { return _compilation->profile_calls();         }
393   bool profile_inlined_calls() { return _compilation->profile_inlined_calls(); }
394   bool profile_checkcasts()    { return _compilation->profile_checkcasts();    }
395   bool profile_parameters()    { return _compilation->profile_parameters();    }
396   bool profile_arguments()     { return _compilation->profile_arguments();     }
397   bool profile_return()        { return _compilation->profile_return();        }
398 
399   Values* args_list_for_profiling(ciMethod* target, int& start, bool may_have_receiver);
400   Values* collect_args_for_profiling(Values* args, ciMethod* target, bool may_have_receiver);
401   void check_args_for_profiling(Values* obj_args, int expected);
402 
403  public:
404   NOT_PRODUCT(void print_stats();)
405 
406   // initialization
407   static void initialize();
408 
409   // public
410   static bool can_trap(ciMethod* method, Bytecodes::Code code) {
411     assert(0 <= code && code < Bytecodes::number_of_java_codes, "illegal bytecode");
412     if (_can_trap[code]) return true;
413     // special handling for finalizer registration
414     return code == Bytecodes::_return && method->intrinsic_id() == vmIntrinsics::_Object_init;
415   }
416 
417   // creation
418   GraphBuilder(Compilation* compilation, IRScope* scope);
419   static void sort_top_into_worklist(BlockList* worklist, BlockBegin* top);
420 
421   BlockBegin* start() const                      { return _start; }
422 };
423 
424 #endif // SHARE_C1_C1_GRAPHBUILDER_HPP