1 /*
  2  * Copyright (c) 2000, 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.
 22  *
 23  */
 24 
 25 #ifndef SHARE_OPTO_OUTPUT_HPP
 26 #define SHARE_OPTO_OUTPUT_HPP
 27 
 28 #include "code/debugInfo.hpp"
 29 #include "code/exceptionHandlerTable.hpp"
 30 #include "metaprogramming/enableIf.hpp"
 31 #include "opto/ad.hpp"
 32 #include "opto/constantTable.hpp"
 33 #include "opto/phase.hpp"
 34 #include "runtime/vm_version.hpp"
 35 #include "utilities/globalDefinitions.hpp"
 36 #include "utilities/macros.hpp"
 37 
 38 class AbstractCompiler;
 39 class Arena;
 40 class Bundle;
 41 class Block;
 42 class Block_Array;
 43 class ciMethod;
 44 class Compile;
 45 class MachNode;
 46 class MachSafePointNode;
 47 class Node;
 48 class PhaseCFG;
 49 #ifndef PRODUCT
 50 #define DEBUG_ARG(x) , x
 51 #else
 52 #define DEBUG_ARG(x)
 53 #endif
 54 
 55 // Define the initial sizes for allocation of the resizable code buffer
 56 enum {
 57   initial_const_capacity =   4 * 1024
 58 };
 59 
 60 class BufferSizingData {
 61 public:
 62   int _stub;
 63   int _code;
 64   int _const;
 65   int _reloc;
 66 
 67   BufferSizingData() :
 68     _stub(0),
 69     _code(0),
 70     _const(0),
 71     _reloc(0)
 72   { };
 73 };
 74 
 75 class C2SafepointPollStubTable {
 76 private:
 77   struct C2SafepointPollStub: public ResourceObj {
 78     uintptr_t _safepoint_offset;
 79     Label     _stub_label;
 80     Label     _trampoline_label;
 81     C2SafepointPollStub(uintptr_t safepoint_offset) :
 82       _safepoint_offset(safepoint_offset),
 83       _stub_label(),
 84       _trampoline_label() {}
 85   };
 86 
 87   GrowableArray<C2SafepointPollStub*> _safepoints;
 88 
 89   static volatile int _stub_size;
 90 
 91   void emit_stub_impl(MacroAssembler& masm, C2SafepointPollStub* entry) const;
 92 
 93   // The selection logic below relieves the need to add dummy files to unsupported platforms.
 94   template <bool enabled>
 95   typename EnableIf<enabled>::type
 96   select_emit_stub(MacroAssembler& masm, C2SafepointPollStub* entry) const {
 97     emit_stub_impl(masm, entry);
 98   }
 99 
100   template <bool enabled>
101   typename EnableIf<!enabled>::type
102   select_emit_stub(MacroAssembler& masm, C2SafepointPollStub* entry) const {}
103 
104   void emit_stub(MacroAssembler& masm, C2SafepointPollStub* entry) const {
105     select_emit_stub<VM_Version::supports_stack_watermark_barrier()>(masm, entry);
106   }
107 
108   int stub_size_lazy() const;
109 
110 public:
111   Label& add_safepoint(uintptr_t safepoint_offset);
112   int estimate_stub_size() const;
113   void emit(CodeBuffer& cb);
114 };
115 
116 class PhaseOutput : public Phase {
117 private:
118   // Instruction bits passed off to the VM
119   int                    _method_size;           // Size of nmethod code segment in bytes
120   CodeBuffer             _code_buffer;           // Where the code is assembled
121   int                    _first_block_size;      // Size of unvalidated entry point code / OSR poison code
122   ExceptionHandlerTable  _handler_table;         // Table of native-code exception handlers
123   ImplicitExceptionTable _inc_table;             // Table of implicit null checks in native code
124   C2SafepointPollStubTable _safepoint_poll_table;// Table for safepoint polls
125   OopMapSet*             _oop_map_set;           // Table of oop maps (one for each safepoint location)
126   BufferBlob*            _scratch_buffer_blob;   // For temporary code buffers.
127   relocInfo*             _scratch_locs_memory;   // For temporary code buffers.
128   int                    _scratch_const_size;    // For temporary code buffers.
129   bool                   _in_scratch_emit_size;  // true when in scratch_emit_size.
130 
131   int                    _frame_slots;           // Size of total frame in stack slots
132   CodeOffsets            _code_offsets;          // Offsets into the code for various interesting entries
133 
134   uint                   _node_bundling_limit;
135   Bundle*                _node_bundling_base;    // Information for instruction bundling
136 
137   // For deopt
138   int                    _orig_pc_slot;
139   int                    _orig_pc_slot_offset_in_bytes;
140 
141   ConstantTable          _constant_table;        // The constant table for this compilation unit.
142 
143   BufferSizingData       _buf_sizes;
144   Block*                 _block;
145   uint                   _index;
146 
147   void perform_mach_node_analysis();
148   void pd_perform_mach_node_analysis();
149 
150 public:
151   PhaseOutput();
152   ~PhaseOutput();
153 
154   // Convert Nodes to instruction bits and pass off to the VM
155   void Output();
156   bool need_stack_bang(int frame_size_in_bytes) const;
157   bool need_register_stack_bang() const;
158   void compute_loop_first_inst_sizes();
159 
160   void install_code(ciMethod*         target,
161                     int               entry_bci,
162                     AbstractCompiler* compiler,
163                     bool              has_unsafe_access,
164                     bool              has_wide_vectors,
165                     RTMState          rtm_state);
166 
167   void install_stub(const char* stub_name);
168 
169   // Constant table
170   ConstantTable& constant_table() { return _constant_table; }
171 
172   // Safepoint poll table
173   C2SafepointPollStubTable* safepoint_poll_table() { return &_safepoint_poll_table; }
174 
175   // Code emission iterator
176   Block* block()   { return _block; }
177   int index()      { return _index; }
178 
179   // The architecture description provides short branch variants for some long
180   // branch instructions. Replace eligible long branches with short branches.
181   void shorten_branches(uint* blk_starts);
182   // If "objs" contains an ObjectValue whose id is "id", returns it, else null.
183   static ObjectValue* sv_for_node_id(GrowableArray<ScopeValue*> *objs, int id);
184   static void set_sv_for_object_node(GrowableArray<ScopeValue*> *objs, ObjectValue* sv);
185   void FillLocArray( int idx, MachSafePointNode* sfpt, Node *local,
186                      GrowableArray<ScopeValue*> *array,
187                      GrowableArray<ScopeValue*> *objs );
188 
189   void Process_OopMap_Node(MachNode *mach, int current_offset);
190 
191   // Initialize code buffer
192   void estimate_buffer_size(int& const_req);
193   CodeBuffer* init_buffer();
194 
195   // Write out basic block data to code buffer
196   void fill_buffer(CodeBuffer* cb, uint* blk_starts);
197 
198   // Compute the information for the exception tables
199   void FillExceptionTables(uint cnt, uint *call_returns, uint *inct_starts, Label *blk_labels);
200 
201   // Perform instruction scheduling and bundling over the sequence of
202   // instructions in backwards order.
203   void ScheduleAndBundle();
204 
205   void install();
206 
207   // Instruction bits passed off to the VM
208   int               code_size()                 { return _method_size; }
209   CodeBuffer*       code_buffer()               { return &_code_buffer; }
210   int               first_block_size()          { return _first_block_size; }
211   void              set_frame_complete(int off) { if (!in_scratch_emit_size()) { _code_offsets.set_value(CodeOffsets::Frame_Complete, off); } }
212   ExceptionHandlerTable*  handler_table()       { return &_handler_table; }
213   ImplicitExceptionTable* inc_table()           { return &_inc_table; }
214   OopMapSet*        oop_map_set()               { return _oop_map_set; }
215 
216   // Scratch buffer
217   BufferBlob*       scratch_buffer_blob()       { return _scratch_buffer_blob; }
218   void         init_scratch_buffer_blob(int const_size);
219   void        clear_scratch_buffer_blob();
220   void          set_scratch_buffer_blob(BufferBlob* b) { _scratch_buffer_blob = b; }
221   relocInfo*        scratch_locs_memory()       { return _scratch_locs_memory; }
222   void          set_scratch_locs_memory(relocInfo* b)  { _scratch_locs_memory = b; }
223   int               scratch_buffer_code_size()  { return (address)scratch_locs_memory() - _scratch_buffer_blob->content_begin(); }
224 
225   // emit to scratch blob, report resulting size
226   uint              scratch_emit_size(const Node* n);
227   void       set_in_scratch_emit_size(bool x)   {        _in_scratch_emit_size = x; }
228   bool           in_scratch_emit_size() const   { return _in_scratch_emit_size;     }
229 
230   enum ScratchBufferBlob {
231     MAX_inst_size       = 2048,
232     MAX_locs_size       = 128, // number of relocInfo elements
233     MAX_const_size      = 128,
234     MAX_stubs_size      = 128
235   };
236 
237   int               frame_slots() const         { return _frame_slots; }
238   int               frame_size_in_words() const; // frame_slots in units of the polymorphic 'words'
239   int               frame_size_in_bytes() const { return _frame_slots << LogBytesPerInt; }
240 
241   int               bang_size_in_bytes() const;
242 
243   uint              node_bundling_limit();
244   Bundle*           node_bundling_base();
245   void          set_node_bundling_limit(uint n) { _node_bundling_limit = n; }
246   void          set_node_bundling_base(Bundle* b) { _node_bundling_base = b; }
247 
248   Bundle* node_bundling(const Node *n);
249   bool valid_bundle_info(const Node *n);
250 
251   bool starts_bundle(const Node *n) const;
252 
253   // Dump formatted assembly
254 #if defined(SUPPORT_OPTO_ASSEMBLY)
255   void dump_asm_on(outputStream* ost, int* pcs, uint pc_limit);
256   void dump_asm(int* pcs = NULL, uint pc_limit = 0) { dump_asm_on(tty, pcs, pc_limit); }
257 #else
258   void dump_asm_on(outputStream* ost, int* pcs, uint pc_limit) { return; }
259   void dump_asm(int* pcs = NULL, uint pc_limit = 0) { return; }
260 #endif
261 
262   // Build OopMaps for each GC point
263   void BuildOopMaps();
264 
265 #ifndef PRODUCT
266   static void print_statistics();
267 #endif
268 };
269 
270 #endif // SHARE_OPTO_OUTPUT_HPP