1 /* 2 * Copyright (c) 1997, 2019, 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_MATCHER_HPP 26 #define SHARE_OPTO_MATCHER_HPP 27 28 #include "libadt/vectset.hpp" 29 #include "memory/resourceArea.hpp" 30 #include "opto/node.hpp" 31 #include "opto/phaseX.hpp" 32 #include "opto/regmask.hpp" 33 34 class Compile; 35 class Node; 36 class MachNode; 37 class MachTypeNode; 38 class MachOper; 39 40 //---------------------------Matcher------------------------------------------- 41 class Matcher : public PhaseTransform { 42 friend class VMStructs; 43 44 public: 45 46 // State and MStack class used in xform() and find_shared() iterative methods. 47 enum Node_State { Pre_Visit, // node has to be pre-visited 48 Visit, // visit node 49 Post_Visit, // post-visit node 50 Alt_Post_Visit // alternative post-visit path 51 }; 52 53 class MStack: public Node_Stack { 54 public: 55 MStack(int size) : Node_Stack(size) { } 56 57 void push(Node *n, Node_State ns) { 58 Node_Stack::push(n, (uint)ns); 59 } 60 void push(Node *n, Node_State ns, Node *parent, int indx) { 61 ++_inode_top; 62 if ((_inode_top + 1) >= _inode_max) grow(); 63 _inode_top->node = parent; 64 _inode_top->indx = (uint)indx; 65 ++_inode_top; 66 _inode_top->node = n; 67 _inode_top->indx = (uint)ns; 68 } 69 Node *parent() { 70 pop(); 71 return node(); 72 } 73 Node_State state() const { 74 return (Node_State)index(); 75 } 76 void set_state(Node_State ns) { 77 set_index((uint)ns); 78 } 79 }; 80 81 private: 82 // Private arena of State objects 83 ResourceArea _states_arena; 84 85 VectorSet _visited; // Visit bits 86 87 // Used to control the Label pass 88 VectorSet _shared; // Shared Ideal Node 89 VectorSet _dontcare; // Nothing the matcher cares about 90 91 // Private methods which perform the actual matching and reduction 92 // Walks the label tree, generating machine nodes 93 MachNode *ReduceInst( State *s, int rule, Node *&mem); 94 void ReduceInst_Chain_Rule( State *s, int rule, Node *&mem, MachNode *mach); 95 uint ReduceInst_Interior(State *s, int rule, Node *&mem, MachNode *mach, uint num_opnds); 96 void ReduceOper( State *s, int newrule, Node *&mem, MachNode *mach ); 97 98 // If this node already matched using "rule", return the MachNode for it. 99 MachNode* find_shared_node(Node* n, uint rule); 100 101 // Convert a dense opcode number to an expanded rule number 102 const int *_reduceOp; 103 const int *_leftOp; 104 const int *_rightOp; 105 106 // Map dense opcode number to info on when rule is swallowed constant. 107 const bool *_swallowed; 108 109 // Map dense rule number to determine if this is an instruction chain rule 110 const uint _begin_inst_chain_rule; 111 const uint _end_inst_chain_rule; 112 113 // We want to clone constants and possible CmpI-variants. 114 // If we do not clone CmpI, then we can have many instances of 115 // condition codes alive at once. This is OK on some chips and 116 // bad on others. Hence the machine-dependent table lookup. 117 const char *_must_clone; 118 119 // Find shared Nodes, or Nodes that otherwise are Matcher roots 120 void find_shared( Node *n ); 121 bool find_shared_visit(MStack& mstack, Node* n, uint opcode, bool& mem_op, int& mem_addr_idx); 122 void find_shared_post_visit(Node* n, uint opcode); 123 124 #ifdef X86 125 bool is_bmi_pattern(Node *n, Node *m); 126 #endif 127 128 // Debug and profile information for nodes in old space: 129 GrowableArray<Node_Notes*>* _old_node_note_array; 130 131 // Node labeling iterator for instruction selection 132 Node *Label_Root( const Node *n, State *svec, Node *control, const Node *mem ); 133 134 Node *transform( Node *dummy ); 135 136 Node_List _projection_list; // For Machine nodes killing many values 137 138 Node_Array _shared_nodes; 139 140 debug_only(Node_Array _old2new_map;) // Map roots of ideal-trees to machine-roots 141 debug_only(Node_Array _new2old_map;) // Maps machine nodes back to ideal 142 143 // Accessors for the inherited field PhaseTransform::_nodes: 144 void grow_new_node_array(uint idx_limit) { 145 _nodes.map(idx_limit-1, NULL); 146 } 147 bool has_new_node(const Node* n) const { 148 return _nodes.at(n->_idx) != NULL; 149 } 150 Node* new_node(const Node* n) const { 151 assert(has_new_node(n), "set before get"); 152 return _nodes.at(n->_idx); 153 } 154 void set_new_node(const Node* n, Node *nn) { 155 assert(!has_new_node(n), "set only once"); 156 _nodes.map(n->_idx, nn); 157 } 158 159 #ifdef ASSERT 160 // Make sure only new nodes are reachable from this node 161 void verify_new_nodes_only(Node* root); 162 163 Node* _mem_node; // Ideal memory node consumed by mach node 164 #endif 165 166 // Mach node for ConP #NULL 167 MachNode* _mach_null; 168 169 void handle_precedence_edges(Node* n, MachNode *mach); 170 171 public: 172 int LabelRootDepth; 173 // Convert ideal machine register to a register mask for spill-loads 174 static const RegMask *idealreg2regmask[]; 175 RegMask *idealreg2spillmask [_last_machine_leaf]; 176 RegMask *idealreg2debugmask [_last_machine_leaf]; 177 RegMask *idealreg2mhdebugmask[_last_machine_leaf]; 178 void init_spill_mask( Node *ret ); 179 // Convert machine register number to register mask 180 static uint mreg2regmask_max; 181 static RegMask mreg2regmask[]; 182 static RegMask STACK_ONLY_mask; 183 184 MachNode* mach_null() const { return _mach_null; } 185 186 bool is_shared( Node *n ) { return _shared.test(n->_idx) != 0; } 187 void set_shared( Node *n ) { _shared.set(n->_idx); } 188 bool is_visited( Node *n ) { return _visited.test(n->_idx) != 0; } 189 void set_visited( Node *n ) { _visited.set(n->_idx); } 190 bool is_dontcare( Node *n ) { return _dontcare.test(n->_idx) != 0; } 191 void set_dontcare( Node *n ) { _dontcare.set(n->_idx); } 192 193 // Mode bit to tell DFA and expand rules whether we are running after 194 // (or during) register selection. Usually, the matcher runs before, 195 // but it will also get called to generate post-allocation spill code. 196 // In this situation, it is a deadly error to attempt to allocate more 197 // temporary registers. 198 bool _allocation_started; 199 200 // Machine register names 201 static const char *regName[]; 202 // Machine register encodings 203 static const unsigned char _regEncode[]; 204 // Machine Node names 205 const char **_ruleName; 206 // Rules that are cheaper to rematerialize than to spill 207 static const uint _begin_rematerialize; 208 static const uint _end_rematerialize; 209 210 // An array of chars, from 0 to _last_Mach_Reg. 211 // No Save = 'N' (for register windows) 212 // Save on Entry = 'E' 213 // Save on Call = 'C' 214 // Always Save = 'A' (same as SOE + SOC) 215 const char *_register_save_policy; 216 const char *_c_reg_save_policy; 217 // Convert a machine register to a machine register type, so-as to 218 // properly match spill code. 219 const int *_register_save_type; 220 // Maps from machine register to boolean; true if machine register can 221 // be holding a call argument in some signature. 222 static bool can_be_java_arg( int reg ); 223 // Maps from machine register to boolean; true if machine register holds 224 // a spillable argument. 225 static bool is_spillable_arg( int reg ); 226 227 // List of IfFalse or IfTrue Nodes that indicate a taken null test. 228 // List is valid in the post-matching space. 229 Node_List _null_check_tests; 230 void collect_null_checks( Node *proj, Node *orig_proj ); 231 void validate_null_checks( ); 232 233 Matcher(); 234 235 // Get a projection node at position pos 236 Node* get_projection(uint pos) { 237 return _projection_list[pos]; 238 } 239 240 // Push a projection node onto the projection list 241 void push_projection(Node* node) { 242 _projection_list.push(node); 243 } 244 245 Node* pop_projection() { 246 return _projection_list.pop(); 247 } 248 249 // Number of nodes in the projection list 250 uint number_of_projections() const { 251 return _projection_list.size(); 252 } 253 254 // Select instructions for entire method 255 void match(); 256 257 // Helper for match 258 OptoReg::Name warp_incoming_stk_arg( VMReg reg ); 259 260 RegMask* return_values_mask(const TypeTuple *range); 261 262 // Transform, then walk. Does implicit DCE while walking. 263 // Name changed from "transform" to avoid it being virtual. 264 Node *xform( Node *old_space_node, int Nodes ); 265 266 // Match a single Ideal Node - turn it into a 1-Node tree; Label & Reduce. 267 MachNode *match_tree( const Node *n ); 268 MachNode *match_sfpt( SafePointNode *sfpt ); 269 // Helper for match_sfpt 270 OptoReg::Name warp_outgoing_stk_arg( VMReg reg, OptoReg::Name begin_out_arg_area, OptoReg::Name &out_arg_limit_per_call ); 271 272 // Initialize first stack mask and related masks. 273 void init_first_stack_mask(); 274 275 // If we should save-on-entry this register 276 bool is_save_on_entry( int reg ); 277 278 // Fixup the save-on-entry registers 279 void Fixup_Save_On_Entry( ); 280 281 // --- Frame handling --- 282 283 // Register number of the stack slot corresponding to the incoming SP. 284 // Per the Big Picture in the AD file, it is: 285 // SharedInfo::stack0 + locks + in_preserve_stack_slots + pad2. 286 OptoReg::Name _old_SP; 287 288 // Register number of the stack slot corresponding to the highest incoming 289 // argument on the stack. Per the Big Picture in the AD file, it is: 290 // _old_SP + out_preserve_stack_slots + incoming argument size. 291 OptoReg::Name _in_arg_limit; 292 293 // Register number of the stack slot corresponding to the new SP. 294 // Per the Big Picture in the AD file, it is: 295 // _in_arg_limit + pad0 296 OptoReg::Name _new_SP; 297 298 // Register number of the stack slot corresponding to the highest outgoing 299 // argument on the stack. Per the Big Picture in the AD file, it is: 300 // _new_SP + max outgoing arguments of all calls 301 OptoReg::Name _out_arg_limit; 302 303 OptoRegPair *_parm_regs; // Array of machine registers per argument 304 RegMask *_calling_convention_mask; // Array of RegMasks per argument 305 306 // Does matcher have a match rule for this ideal node? 307 static const bool has_match_rule(int opcode); 308 static const bool _hasMatchRule[_last_opcode]; 309 310 // Does matcher have a match rule for this ideal node and is the 311 // predicate (if there is one) true? 312 // NOTE: If this function is used more commonly in the future, ADLC 313 // should generate this one. 314 static const bool match_rule_supported(int opcode); 315 316 // identify extra cases that we might want to provide match rules for 317 // e.g. Op_ vector nodes and other intrinsics while guarding with vlen 318 static const bool match_rule_supported_vector(int opcode, int vlen); 319 320 // Some microarchitectures have mask registers used on vectors 321 static const bool has_predicated_vectors(void); 322 323 // Some uarchs have different sized float register resources 324 static const int float_pressure(int default_pressure_threshold); 325 326 // Used to determine if we have fast l2f conversion 327 // USII has it, USIII doesn't 328 static const bool convL2FSupported(void); 329 330 // Vector width in bytes 331 static const int vector_width_in_bytes(BasicType bt); 332 333 // Limits on vector size (number of elements). 334 static const int max_vector_size(const BasicType bt); 335 static const int min_vector_size(const BasicType bt); 336 static const bool vector_size_supported(const BasicType bt, int size) { 337 return (Matcher::max_vector_size(bt) >= size && 338 Matcher::min_vector_size(bt) <= size); 339 } 340 341 // Vector ideal reg 342 static const uint vector_ideal_reg(int len); 343 static const uint vector_shift_count_ideal_reg(int len); 344 345 // CPU supports misaligned vectors store/load. 346 static const bool misaligned_vectors_ok(); 347 348 // Should original key array reference be passed to AES stubs 349 static const bool pass_original_key_for_aes(); 350 351 // Used to determine a "low complexity" 64-bit constant. (Zero is simple.) 352 // The standard of comparison is one (StoreL ConL) vs. two (StoreI ConI). 353 // Depends on the details of 64-bit constant generation on the CPU. 354 static const bool isSimpleConstant64(jlong con); 355 356 // These calls are all generated by the ADLC 357 358 // TRUE - grows up, FALSE - grows down (Intel) 359 virtual bool stack_direction() const; 360 361 // Java-Java calling convention 362 // (what you use when Java calls Java) 363 364 // Alignment of stack in bytes, standard Intel word alignment is 4. 365 // Sparc probably wants at least double-word (8). 366 static uint stack_alignment_in_bytes(); 367 // Alignment of stack, measured in stack slots. 368 // The size of stack slots is defined by VMRegImpl::stack_slot_size. 369 static uint stack_alignment_in_slots() { 370 return stack_alignment_in_bytes() / (VMRegImpl::stack_slot_size); 371 } 372 373 // Array mapping arguments to registers. Argument 0 is usually the 'this' 374 // pointer. Registers can include stack-slots and regular registers. 375 static void calling_convention( BasicType *, VMRegPair *, uint len, bool is_outgoing ); 376 377 // Convert a sig into a calling convention register layout 378 // and find interesting things about it. 379 static OptoReg::Name find_receiver( bool is_outgoing ); 380 // Return address register. On Intel it is a stack-slot. On PowerPC 381 // it is the Link register. On Sparc it is r31? 382 virtual OptoReg::Name return_addr() const; 383 RegMask _return_addr_mask; 384 // Return value register. On Intel it is EAX. On Sparc i0/o0. 385 static OptoRegPair return_value(uint ideal_reg, bool is_outgoing); 386 static OptoRegPair c_return_value(uint ideal_reg, bool is_outgoing); 387 RegMask* _return_values_mask; 388 // Inline Cache Register 389 static OptoReg::Name inline_cache_reg(); 390 static int inline_cache_reg_encode(); 391 392 // Register for DIVI projection of divmodI 393 static RegMask divI_proj_mask(); 394 // Register for MODI projection of divmodI 395 static RegMask modI_proj_mask(); 396 397 // Register for DIVL projection of divmodL 398 static RegMask divL_proj_mask(); 399 // Register for MODL projection of divmodL 400 static RegMask modL_proj_mask(); 401 402 // Use hardware DIV instruction when it is faster than 403 // a code which use multiply for division by constant. 404 static bool use_asm_for_ldiv_by_con( jlong divisor ); 405 406 static const RegMask method_handle_invoke_SP_save_mask(); 407 408 // Java-Interpreter calling convention 409 // (what you use when calling between compiled-Java and Interpreted-Java 410 411 // Number of callee-save + always-save registers 412 // Ignores frame pointer and "special" registers 413 static int number_of_saved_registers(); 414 415 // The Method-klass-holder may be passed in the inline_cache_reg 416 // and then expanded into the inline_cache_reg and a method_oop register 417 418 static OptoReg::Name interpreter_method_oop_reg(); 419 static int interpreter_method_oop_reg_encode(); 420 421 static OptoReg::Name compiler_method_oop_reg(); 422 static const RegMask &compiler_method_oop_reg_mask(); 423 static int compiler_method_oop_reg_encode(); 424 425 // Interpreter's Frame Pointer Register 426 static OptoReg::Name interpreter_frame_pointer_reg(); 427 428 // Java-Native calling convention 429 // (what you use when intercalling between Java and C++ code) 430 431 // Array mapping arguments to registers. Argument 0 is usually the 'this' 432 // pointer. Registers can include stack-slots and regular registers. 433 static void c_calling_convention( BasicType*, VMRegPair *, uint ); 434 // Frame pointer. The frame pointer is kept at the base of the stack 435 // and so is probably the stack pointer for most machines. On Intel 436 // it is ESP. On the PowerPC it is R1. On Sparc it is SP. 437 OptoReg::Name c_frame_pointer() const; 438 static RegMask c_frame_ptr_mask; 439 440 // !!!!! Special stuff for building ScopeDescs 441 virtual int regnum_to_fpu_offset(int regnum); 442 443 // Is this branch offset small enough to be addressed by a short branch? 444 bool is_short_branch_offset(int rule, int br_size, int offset); 445 446 // Optional scaling for the parameter to the ClearArray/CopyArray node. 447 static const bool init_array_count_is_in_bytes; 448 449 // Some hardware needs 2 CMOV's for longs. 450 static const int long_cmove_cost(); 451 452 // Some hardware have expensive CMOV for float and double. 453 static const int float_cmove_cost(); 454 455 // Should the Matcher clone shifts on addressing modes, expecting them to 456 // be subsumed into complex addressing expressions or compute them into 457 // registers? True for Intel but false for most RISCs 458 bool clone_address_expressions(AddPNode* m, MStack& mstack, VectorSet& address_visited); 459 // Clone base + offset address expression 460 bool clone_base_plus_offset_address(AddPNode* m, MStack& mstack, VectorSet& address_visited); 461 462 static bool narrow_oop_use_complex_address(); 463 static bool narrow_klass_use_complex_address(); 464 465 static bool const_oop_prefer_decode(); 466 static bool const_klass_prefer_decode(); 467 468 // Generate implicit null check for narrow oops if it can fold 469 // into address expression (x64). 470 // 471 // [R12 + narrow_oop_reg<<3 + offset] // fold into address expression 472 // NullCheck narrow_oop_reg 473 // 474 // When narrow oops can't fold into address expression (Sparc) and 475 // base is not null use decode_not_null and normal implicit null check. 476 // Note, decode_not_null node can be used here since it is referenced 477 // only on non null path but it requires special handling, see 478 // collect_null_checks(): 479 // 480 // decode_not_null narrow_oop_reg, oop_reg // 'shift' and 'add base' 481 // [oop_reg + offset] 482 // NullCheck oop_reg 483 // 484 // With Zero base and when narrow oops can not fold into address 485 // expression use normal implicit null check since only shift 486 // is needed to decode narrow oop. 487 // 488 // decode narrow_oop_reg, oop_reg // only 'shift' 489 // [oop_reg + offset] 490 // NullCheck oop_reg 491 // 492 inline static bool gen_narrow_oop_implicit_null_checks() { 493 // Advice matcher to perform null checks on the narrow oop side. 494 // Implicit checks are not possible on the uncompressed oop side anyway 495 // (at least not for read accesses). 496 // Performs significantly better (especially on Power 6). 497 if (!os::zero_page_read_protected()) { 498 return true; 499 } 500 return Universe::narrow_oop_use_implicit_null_checks() && 501 (narrow_oop_use_complex_address() || 502 Universe::narrow_oop_base() != NULL); 503 } 504 505 // Is it better to copy float constants, or load them directly from memory? 506 // Intel can load a float constant from a direct address, requiring no 507 // extra registers. Most RISCs will have to materialize an address into a 508 // register first, so they may as well materialize the constant immediately. 509 static const bool rematerialize_float_constants; 510 511 // If CPU can load and store mis-aligned doubles directly then no fixup is 512 // needed. Else we split the double into 2 integer pieces and move it 513 // piece-by-piece. Only happens when passing doubles into C code or when 514 // calling i2c adapters as the Java calling convention forces doubles to be 515 // aligned. 516 static const bool misaligned_doubles_ok; 517 518 // Does the CPU require postalloc expand (see block.cpp for description of 519 // postalloc expand)? 520 static const bool require_postalloc_expand; 521 522 // Perform a platform dependent implicit null fixup. This is needed 523 // on windows95 to take care of some unusual register constraints. 524 void pd_implicit_null_fixup(MachNode *load, uint idx); 525 526 // Advertise here if the CPU requires explicit rounding operations 527 // to implement the UseStrictFP mode. 528 static const bool strict_fp_requires_explicit_rounding; 529 530 // Are floats conerted to double when stored to stack during deoptimization? 531 static bool float_in_double(); 532 // Do ints take an entire long register or just half? 533 static const bool int_in_long; 534 535 // Do the processor's shift instructions only use the low 5/6 bits 536 // of the count for 32/64 bit ints? If not we need to do the masking 537 // ourselves. 538 static const bool need_masked_shift_count; 539 540 // Whether code generation need accurate ConvI2L types. 541 static const bool convi2l_type_required; 542 543 // This routine is run whenever a graph fails to match. 544 // If it returns, the compiler should bailout to interpreter without error. 545 // In non-product mode, SoftMatchFailure is false to detect non-canonical 546 // graphs. Print a message and exit. 547 static void soft_match_failure() { 548 if( SoftMatchFailure ) return; 549 else { fatal("SoftMatchFailure is not allowed except in product"); } 550 } 551 552 // Check for a following volatile memory barrier without an 553 // intervening load and thus we don't need a barrier here. We 554 // retain the Node to act as a compiler ordering barrier. 555 static bool post_store_load_barrier(const Node* mb); 556 557 // Does n lead to an uncommon trap that can cause deoptimization? 558 static bool branches_to_uncommon_trap(const Node *n); 559 560 #ifdef ASSERT 561 void dump_old2new_map(); // machine-independent to machine-dependent 562 563 Node* find_old_node(Node* new_node) { 564 return _new2old_map[new_node->_idx]; 565 } 566 #endif 567 }; 568 569 #endif // SHARE_OPTO_MATCHER_HPP