1 /* 2 * Copyright (c) 1998, 2024, 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 #include "precompiled.hpp" 26 #include "asm/assembler.inline.hpp" 27 #include "asm/macroAssembler.inline.hpp" 28 #include "code/compiledIC.hpp" 29 #include "code/debugInfo.hpp" 30 #include "code/debugInfoRec.hpp" 31 #include "compiler/compileBroker.hpp" 32 #include "compiler/compilerDirectives.hpp" 33 #include "compiler/disassembler.hpp" 34 #include "compiler/oopMap.hpp" 35 #include "gc/shared/barrierSet.hpp" 36 #include "gc/shared/c2/barrierSetC2.hpp" 37 #include "memory/allocation.inline.hpp" 38 #include "memory/allocation.hpp" 39 #include "opto/ad.hpp" 40 #include "opto/block.hpp" 41 #include "opto/c2compiler.hpp" 42 #include "opto/c2_MacroAssembler.hpp" 43 #include "opto/callnode.hpp" 44 #include "opto/cfgnode.hpp" 45 #include "opto/locknode.hpp" 46 #include "opto/machnode.hpp" 47 #include "opto/node.hpp" 48 #include "opto/optoreg.hpp" 49 #include "opto/output.hpp" 50 #include "opto/regalloc.hpp" 51 #include "opto/runtime.hpp" 52 #include "opto/subnode.hpp" 53 #include "opto/type.hpp" 54 #include "runtime/handles.inline.hpp" 55 #include "runtime/sharedRuntime.hpp" 56 #include "utilities/macros.hpp" 57 #include "utilities/powerOfTwo.hpp" 58 #include "utilities/xmlstream.hpp" 59 60 #ifndef PRODUCT 61 #define DEBUG_ARG(x) , x 62 #else 63 #define DEBUG_ARG(x) 64 #endif 65 66 //------------------------------Scheduling---------------------------------- 67 // This class contains all the information necessary to implement instruction 68 // scheduling and bundling. 69 class Scheduling { 70 71 private: 72 // Arena to use 73 Arena *_arena; 74 75 // Control-Flow Graph info 76 PhaseCFG *_cfg; 77 78 // Register Allocation info 79 PhaseRegAlloc *_regalloc; 80 81 // Number of nodes in the method 82 uint _node_bundling_limit; 83 84 // List of scheduled nodes. Generated in reverse order 85 Node_List _scheduled; 86 87 // List of nodes currently available for choosing for scheduling 88 Node_List _available; 89 90 // For each instruction beginning a bundle, the number of following 91 // nodes to be bundled with it. 92 Bundle *_node_bundling_base; 93 94 // Mapping from register to Node 95 Node_List _reg_node; 96 97 // Free list for pinch nodes. 98 Node_List _pinch_free_list; 99 100 // Number of uses of this node within the containing basic block. 101 short *_uses; 102 103 // Schedulable portion of current block. Skips Region/Phi/CreateEx up 104 // front, branch+proj at end. Also skips Catch/CProj (same as 105 // branch-at-end), plus just-prior exception-throwing call. 106 uint _bb_start, _bb_end; 107 108 // Latency from the end of the basic block as scheduled 109 unsigned short *_current_latency; 110 111 // Remember the next node 112 Node *_next_node; 113 114 // Use this for an unconditional branch delay slot 115 Node *_unconditional_delay_slot; 116 117 // Pointer to a Nop 118 MachNopNode *_nop; 119 120 // Length of the current bundle, in instructions 121 uint _bundle_instr_count; 122 123 // Current Cycle number, for computing latencies and bundling 124 uint _bundle_cycle_number; 125 126 // Bundle information 127 Pipeline_Use_Element _bundle_use_elements[resource_count]; 128 Pipeline_Use _bundle_use; 129 130 // Dump the available list 131 void dump_available() const; 132 133 public: 134 Scheduling(Arena *arena, Compile &compile); 135 136 // Destructor 137 NOT_PRODUCT( ~Scheduling(); ) 138 139 // Step ahead "i" cycles 140 void step(uint i); 141 142 // Step ahead 1 cycle, and clear the bundle state (for example, 143 // at a branch target) 144 void step_and_clear(); 145 146 Bundle* node_bundling(const Node *n) { 147 assert(valid_bundle_info(n), "oob"); 148 return (&_node_bundling_base[n->_idx]); 149 } 150 151 bool valid_bundle_info(const Node *n) const { 152 return (_node_bundling_limit > n->_idx); 153 } 154 155 bool starts_bundle(const Node *n) const { 156 return (_node_bundling_limit > n->_idx && _node_bundling_base[n->_idx].starts_bundle()); 157 } 158 159 // Do the scheduling 160 void DoScheduling(); 161 162 // Compute the register antidependencies within a basic block 163 void ComputeRegisterAntidependencies(Block *bb); 164 void verify_do_def( Node *n, OptoReg::Name def, const char *msg ); 165 void verify_good_schedule( Block *b, const char *msg ); 166 void anti_do_def( Block *b, Node *def, OptoReg::Name def_reg, int is_def ); 167 void anti_do_use( Block *b, Node *use, OptoReg::Name use_reg ); 168 169 // Add a node to the current bundle 170 void AddNodeToBundle(Node *n, const Block *bb); 171 172 // Return an integer less than, equal to, or greater than zero 173 // if the stack offset of the first argument is respectively 174 // less than, equal to, or greater than the second. 175 int compare_two_spill_nodes(Node* first, Node* second); 176 177 // Add a node to the list of available nodes 178 void AddNodeToAvailableList(Node *n); 179 180 // Compute the local use count for the nodes in a block, and compute 181 // the list of instructions with no uses in the block as available 182 void ComputeUseCount(const Block *bb); 183 184 // Choose an instruction from the available list to add to the bundle 185 Node * ChooseNodeToBundle(); 186 187 // See if this Node fits into the currently accumulating bundle 188 bool NodeFitsInBundle(Node *n); 189 190 // Decrement the use count for a node 191 void DecrementUseCounts(Node *n, const Block *bb); 192 193 // Garbage collect pinch nodes for reuse by other blocks. 194 void garbage_collect_pinch_nodes(); 195 // Clean up a pinch node for reuse (helper for above). 196 void cleanup_pinch( Node *pinch ); 197 198 // Information for statistics gathering 199 #ifndef PRODUCT 200 private: 201 // Gather information on size of nops relative to total 202 uint _branches, _unconditional_delays; 203 204 static uint _total_nop_size, _total_method_size; 205 static uint _total_branches, _total_unconditional_delays; 206 static uint _total_instructions_per_bundle[Pipeline::_max_instrs_per_cycle+1]; 207 208 public: 209 static void print_statistics(); 210 211 static void increment_instructions_per_bundle(uint i) { 212 _total_instructions_per_bundle[i]++; 213 } 214 215 static void increment_nop_size(uint s) { 216 _total_nop_size += s; 217 } 218 219 static void increment_method_size(uint s) { 220 _total_method_size += s; 221 } 222 #endif 223 224 }; 225 226 PhaseOutput::PhaseOutput() 227 : Phase(Phase::Output), 228 _code_buffer("Compile::Fill_buffer"), 229 _first_block_size(0), 230 _handler_table(), 231 _inc_table(), 232 _stub_list(), 233 _oop_map_set(nullptr), 234 _scratch_buffer_blob(nullptr), 235 _scratch_locs_memory(nullptr), 236 _scratch_const_size(-1), 237 _in_scratch_emit_size(false), 238 _frame_slots(0), 239 _code_offsets(), 240 _node_bundling_limit(0), 241 _node_bundling_base(nullptr), 242 _orig_pc_slot(0), 243 _orig_pc_slot_offset_in_bytes(0), 244 _buf_sizes(), 245 _block(nullptr), 246 _index(0) { 247 C->set_output(this); 248 if (C->stub_name() == nullptr) { 249 _orig_pc_slot = C->fixed_slots() - (sizeof(address) / VMRegImpl::stack_slot_size); 250 } 251 } 252 253 PhaseOutput::~PhaseOutput() { 254 C->set_output(nullptr); 255 if (_scratch_buffer_blob != nullptr) { 256 BufferBlob::free(_scratch_buffer_blob); 257 } 258 } 259 260 void PhaseOutput::perform_mach_node_analysis() { 261 // Late barrier analysis must be done after schedule and bundle 262 // Otherwise liveness based spilling will fail 263 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 264 bs->late_barrier_analysis(); 265 266 pd_perform_mach_node_analysis(); 267 268 C->print_method(CompilerPhaseType::PHASE_MACH_ANALYSIS, 3); 269 } 270 271 // Convert Nodes to instruction bits and pass off to the VM 272 void PhaseOutput::Output() { 273 // RootNode goes 274 assert( C->cfg()->get_root_block()->number_of_nodes() == 0, "" ); 275 276 // The number of new nodes (mostly MachNop) is proportional to 277 // the number of java calls and inner loops which are aligned. 278 if ( C->check_node_count((NodeLimitFudgeFactor + C->java_calls()*3 + 279 C->inner_loops()*(OptoLoopAlignment-1)), 280 "out of nodes before code generation" ) ) { 281 return; 282 } 283 // Make sure I can find the Start Node 284 Block *entry = C->cfg()->get_block(1); 285 Block *broot = C->cfg()->get_root_block(); 286 287 const StartNode *start = entry->head()->as_Start(); 288 289 // Replace StartNode with prolog 290 MachPrologNode *prolog = new MachPrologNode(); 291 entry->map_node(prolog, 0); 292 C->cfg()->map_node_to_block(prolog, entry); 293 C->cfg()->unmap_node_from_block(start); // start is no longer in any block 294 295 // Virtual methods need an unverified entry point 296 297 if( C->is_osr_compilation() ) { 298 if( PoisonOSREntry ) { 299 // TODO: Should use a ShouldNotReachHereNode... 300 C->cfg()->insert( broot, 0, new MachBreakpointNode() ); 301 } 302 } else { 303 if( C->method() && !C->method()->flags().is_static() ) { 304 // Insert unvalidated entry point 305 C->cfg()->insert( broot, 0, new MachUEPNode() ); 306 } 307 308 } 309 310 // Break before main entry point 311 if ((C->method() && C->directive()->BreakAtExecuteOption) || 312 (OptoBreakpoint && C->is_method_compilation()) || 313 (OptoBreakpointOSR && C->is_osr_compilation()) || 314 (OptoBreakpointC2R && !C->method()) ) { 315 // checking for C->method() means that OptoBreakpoint does not apply to 316 // runtime stubs or frame converters 317 C->cfg()->insert( entry, 1, new MachBreakpointNode() ); 318 } 319 320 // Insert epilogs before every return 321 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) { 322 Block* block = C->cfg()->get_block(i); 323 if (!block->is_connector() && block->non_connector_successor(0) == C->cfg()->get_root_block()) { // Found a program exit point? 324 Node* m = block->end(); 325 if (m->is_Mach() && m->as_Mach()->ideal_Opcode() != Op_Halt) { 326 MachEpilogNode* epilog = new MachEpilogNode(m->as_Mach()->ideal_Opcode() == Op_Return); 327 block->add_inst(epilog); 328 C->cfg()->map_node_to_block(epilog, block); 329 } 330 } 331 } 332 333 // Keeper of sizing aspects 334 _buf_sizes = BufferSizingData(); 335 336 // Initialize code buffer 337 estimate_buffer_size(_buf_sizes._const); 338 if (C->failing()) return; 339 340 // Pre-compute the length of blocks and replace 341 // long branches with short if machine supports it. 342 // Must be done before ScheduleAndBundle due to SPARC delay slots 343 uint* blk_starts = NEW_RESOURCE_ARRAY(uint, C->cfg()->number_of_blocks() + 1); 344 blk_starts[0] = 0; 345 shorten_branches(blk_starts); 346 347 ScheduleAndBundle(); 348 if (C->failing()) { 349 return; 350 } 351 352 perform_mach_node_analysis(); 353 354 // Complete sizing of codebuffer 355 CodeBuffer* cb = init_buffer(); 356 if (cb == nullptr || C->failing()) { 357 return; 358 } 359 360 BuildOopMaps(); 361 362 if (C->failing()) { 363 return; 364 } 365 366 fill_buffer(cb, blk_starts); 367 } 368 369 bool PhaseOutput::need_stack_bang(int frame_size_in_bytes) const { 370 // Determine if we need to generate a stack overflow check. 371 // Do it if the method is not a stub function and 372 // has java calls or has frame size > vm_page_size/8. 373 // The debug VM checks that deoptimization doesn't trigger an 374 // unexpected stack overflow (compiled method stack banging should 375 // guarantee it doesn't happen) so we always need the stack bang in 376 // a debug VM. 377 return (C->stub_function() == nullptr && 378 (C->has_java_calls() || frame_size_in_bytes > (int)(os::vm_page_size())>>3 379 DEBUG_ONLY(|| true))); 380 } 381 382 bool PhaseOutput::need_register_stack_bang() const { 383 // Determine if we need to generate a register stack overflow check. 384 // This is only used on architectures which have split register 385 // and memory stacks (ie. IA64). 386 // Bang if the method is not a stub function and has java calls 387 return (C->stub_function() == nullptr && C->has_java_calls()); 388 } 389 390 391 // Compute the size of first NumberOfLoopInstrToAlign instructions at the top 392 // of a loop. When aligning a loop we need to provide enough instructions 393 // in cpu's fetch buffer to feed decoders. The loop alignment could be 394 // avoided if we have enough instructions in fetch buffer at the head of a loop. 395 // By default, the size is set to 999999 by Block's constructor so that 396 // a loop will be aligned if the size is not reset here. 397 // 398 // Note: Mach instructions could contain several HW instructions 399 // so the size is estimated only. 400 // 401 void PhaseOutput::compute_loop_first_inst_sizes() { 402 // The next condition is used to gate the loop alignment optimization. 403 // Don't aligned a loop if there are enough instructions at the head of a loop 404 // or alignment padding is larger then MaxLoopPad. By default, MaxLoopPad 405 // is equal to OptoLoopAlignment-1 except on new Intel cpus, where it is 406 // equal to 11 bytes which is the largest address NOP instruction. 407 if (MaxLoopPad < OptoLoopAlignment - 1) { 408 uint last_block = C->cfg()->number_of_blocks() - 1; 409 for (uint i = 1; i <= last_block; i++) { 410 Block* block = C->cfg()->get_block(i); 411 // Check the first loop's block which requires an alignment. 412 if (block->loop_alignment() > (uint)relocInfo::addr_unit()) { 413 uint sum_size = 0; 414 uint inst_cnt = NumberOfLoopInstrToAlign; 415 inst_cnt = block->compute_first_inst_size(sum_size, inst_cnt, C->regalloc()); 416 417 // Check subsequent fallthrough blocks if the loop's first 418 // block(s) does not have enough instructions. 419 Block *nb = block; 420 while(inst_cnt > 0 && 421 i < last_block && 422 !C->cfg()->get_block(i + 1)->has_loop_alignment() && 423 !nb->has_successor(block)) { 424 i++; 425 nb = C->cfg()->get_block(i); 426 inst_cnt = nb->compute_first_inst_size(sum_size, inst_cnt, C->regalloc()); 427 } // while( inst_cnt > 0 && i < last_block ) 428 429 block->set_first_inst_size(sum_size); 430 } // f( b->head()->is_Loop() ) 431 } // for( i <= last_block ) 432 } // if( MaxLoopPad < OptoLoopAlignment-1 ) 433 } 434 435 // The architecture description provides short branch variants for some long 436 // branch instructions. Replace eligible long branches with short branches. 437 void PhaseOutput::shorten_branches(uint* blk_starts) { 438 439 Compile::TracePhase tp("shorten branches", &timers[_t_shortenBranches]); 440 441 // Compute size of each block, method size, and relocation information size 442 uint nblocks = C->cfg()->number_of_blocks(); 443 444 uint* jmp_offset = NEW_RESOURCE_ARRAY(uint,nblocks); 445 uint* jmp_size = NEW_RESOURCE_ARRAY(uint,nblocks); 446 int* jmp_nidx = NEW_RESOURCE_ARRAY(int ,nblocks); 447 448 // Collect worst case block paddings 449 int* block_worst_case_pad = NEW_RESOURCE_ARRAY(int, nblocks); 450 memset(block_worst_case_pad, 0, nblocks * sizeof(int)); 451 452 DEBUG_ONLY( uint *jmp_target = NEW_RESOURCE_ARRAY(uint,nblocks); ) 453 DEBUG_ONLY( uint *jmp_rule = NEW_RESOURCE_ARRAY(uint,nblocks); ) 454 455 bool has_short_branch_candidate = false; 456 457 // Initialize the sizes to 0 458 int code_size = 0; // Size in bytes of generated code 459 int stub_size = 0; // Size in bytes of all stub entries 460 // Size in bytes of all relocation entries, including those in local stubs. 461 // Start with 2-bytes of reloc info for the unvalidated entry point 462 int reloc_size = 1; // Number of relocation entries 463 464 // Make three passes. The first computes pessimistic blk_starts, 465 // relative jmp_offset and reloc_size information. The second performs 466 // short branch substitution using the pessimistic sizing. The 467 // third inserts nops where needed. 468 469 // Step one, perform a pessimistic sizing pass. 470 uint last_call_adr = max_juint; 471 uint last_avoid_back_to_back_adr = max_juint; 472 uint nop_size = (new MachNopNode())->size(C->regalloc()); 473 for (uint i = 0; i < nblocks; i++) { // For all blocks 474 Block* block = C->cfg()->get_block(i); 475 _block = block; 476 477 // During short branch replacement, we store the relative (to blk_starts) 478 // offset of jump in jmp_offset, rather than the absolute offset of jump. 479 // This is so that we do not need to recompute sizes of all nodes when 480 // we compute correct blk_starts in our next sizing pass. 481 jmp_offset[i] = 0; 482 jmp_size[i] = 0; 483 jmp_nidx[i] = -1; 484 DEBUG_ONLY( jmp_target[i] = 0; ) 485 DEBUG_ONLY( jmp_rule[i] = 0; ) 486 487 // Sum all instruction sizes to compute block size 488 uint last_inst = block->number_of_nodes(); 489 uint blk_size = 0; 490 for (uint j = 0; j < last_inst; j++) { 491 _index = j; 492 Node* nj = block->get_node(_index); 493 // Handle machine instruction nodes 494 if (nj->is_Mach()) { 495 MachNode* mach = nj->as_Mach(); 496 blk_size += (mach->alignment_required() - 1) * relocInfo::addr_unit(); // assume worst case padding 497 reloc_size += mach->reloc(); 498 if (mach->is_MachCall()) { 499 // add size information for trampoline stub 500 // class CallStubImpl is platform-specific and defined in the *.ad files. 501 stub_size += CallStubImpl::size_call_trampoline(); 502 reloc_size += CallStubImpl::reloc_call_trampoline(); 503 504 MachCallNode *mcall = mach->as_MachCall(); 505 // This destination address is NOT PC-relative 506 507 mcall->method_set((intptr_t)mcall->entry_point()); 508 509 if (mcall->is_MachCallJava() && mcall->as_MachCallJava()->_method) { 510 stub_size += CompiledDirectCall::to_interp_stub_size(); 511 reloc_size += CompiledDirectCall::reloc_to_interp_stub(); 512 } 513 } else if (mach->is_MachSafePoint()) { 514 // If call/safepoint are adjacent, account for possible 515 // nop to disambiguate the two safepoints. 516 // ScheduleAndBundle() can rearrange nodes in a block, 517 // check for all offsets inside this block. 518 if (last_call_adr >= blk_starts[i]) { 519 blk_size += nop_size; 520 } 521 } 522 if (mach->avoid_back_to_back(MachNode::AVOID_BEFORE)) { 523 // Nop is inserted between "avoid back to back" instructions. 524 // ScheduleAndBundle() can rearrange nodes in a block, 525 // check for all offsets inside this block. 526 if (last_avoid_back_to_back_adr >= blk_starts[i]) { 527 blk_size += nop_size; 528 } 529 } 530 if (mach->may_be_short_branch()) { 531 if (!nj->is_MachBranch()) { 532 #ifndef PRODUCT 533 nj->dump(3); 534 #endif 535 Unimplemented(); 536 } 537 assert(jmp_nidx[i] == -1, "block should have only one branch"); 538 jmp_offset[i] = blk_size; 539 jmp_size[i] = nj->size(C->regalloc()); 540 jmp_nidx[i] = j; 541 has_short_branch_candidate = true; 542 } 543 } 544 blk_size += nj->size(C->regalloc()); 545 // Remember end of call offset 546 if (nj->is_MachCall() && !nj->is_MachCallLeaf()) { 547 last_call_adr = blk_starts[i]+blk_size; 548 } 549 // Remember end of avoid_back_to_back offset 550 if (nj->is_Mach() && nj->as_Mach()->avoid_back_to_back(MachNode::AVOID_AFTER)) { 551 last_avoid_back_to_back_adr = blk_starts[i]+blk_size; 552 } 553 } 554 555 // When the next block starts a loop, we may insert pad NOP 556 // instructions. Since we cannot know our future alignment, 557 // assume the worst. 558 if (i < nblocks - 1) { 559 Block* nb = C->cfg()->get_block(i + 1); 560 int max_loop_pad = nb->code_alignment()-relocInfo::addr_unit(); 561 if (max_loop_pad > 0) { 562 assert(is_power_of_2(max_loop_pad+relocInfo::addr_unit()), ""); 563 // Adjust last_call_adr and/or last_avoid_back_to_back_adr. 564 // If either is the last instruction in this block, bump by 565 // max_loop_pad in lock-step with blk_size, so sizing 566 // calculations in subsequent blocks still can conservatively 567 // detect that it may the last instruction in this block. 568 if (last_call_adr == blk_starts[i]+blk_size) { 569 last_call_adr += max_loop_pad; 570 } 571 if (last_avoid_back_to_back_adr == blk_starts[i]+blk_size) { 572 last_avoid_back_to_back_adr += max_loop_pad; 573 } 574 blk_size += max_loop_pad; 575 block_worst_case_pad[i + 1] = max_loop_pad; 576 } 577 } 578 579 // Save block size; update total method size 580 blk_starts[i+1] = blk_starts[i]+blk_size; 581 } 582 583 // Step two, replace eligible long jumps. 584 bool progress = true; 585 uint last_may_be_short_branch_adr = max_juint; 586 while (has_short_branch_candidate && progress) { 587 progress = false; 588 has_short_branch_candidate = false; 589 int adjust_block_start = 0; 590 for (uint i = 0; i < nblocks; i++) { 591 Block* block = C->cfg()->get_block(i); 592 int idx = jmp_nidx[i]; 593 MachNode* mach = (idx == -1) ? nullptr: block->get_node(idx)->as_Mach(); 594 if (mach != nullptr && mach->may_be_short_branch()) { 595 #ifdef ASSERT 596 assert(jmp_size[i] > 0 && mach->is_MachBranch(), "sanity"); 597 int j; 598 // Find the branch; ignore trailing NOPs. 599 for (j = block->number_of_nodes()-1; j>=0; j--) { 600 Node* n = block->get_node(j); 601 if (!n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con) 602 break; 603 } 604 assert(j >= 0 && j == idx && block->get_node(j) == (Node*)mach, "sanity"); 605 #endif 606 int br_size = jmp_size[i]; 607 int br_offs = blk_starts[i] + jmp_offset[i]; 608 609 // This requires the TRUE branch target be in succs[0] 610 uint bnum = block->non_connector_successor(0)->_pre_order; 611 int offset = blk_starts[bnum] - br_offs; 612 if (bnum > i) { // adjust following block's offset 613 offset -= adjust_block_start; 614 } 615 616 // This block can be a loop header, account for the padding 617 // in the previous block. 618 int block_padding = block_worst_case_pad[i]; 619 assert(i == 0 || block_padding == 0 || br_offs >= block_padding, "Should have at least a padding on top"); 620 // In the following code a nop could be inserted before 621 // the branch which will increase the backward distance. 622 bool needs_padding = ((uint)(br_offs - block_padding) == last_may_be_short_branch_adr); 623 assert(!needs_padding || jmp_offset[i] == 0, "padding only branches at the beginning of block"); 624 625 if (needs_padding && offset <= 0) 626 offset -= nop_size; 627 628 if (C->matcher()->is_short_branch_offset(mach->rule(), br_size, offset)) { 629 // We've got a winner. Replace this branch. 630 MachNode* replacement = mach->as_MachBranch()->short_branch_version(); 631 632 // Update the jmp_size. 633 int new_size = replacement->size(C->regalloc()); 634 int diff = br_size - new_size; 635 assert(diff >= (int)nop_size, "short_branch size should be smaller"); 636 // Conservatively take into account padding between 637 // avoid_back_to_back branches. Previous branch could be 638 // converted into avoid_back_to_back branch during next 639 // rounds. 640 if (needs_padding && replacement->avoid_back_to_back(MachNode::AVOID_BEFORE)) { 641 jmp_offset[i] += nop_size; 642 diff -= nop_size; 643 } 644 adjust_block_start += diff; 645 block->map_node(replacement, idx); 646 mach->subsume_by(replacement, C); 647 mach = replacement; 648 progress = true; 649 650 jmp_size[i] = new_size; 651 DEBUG_ONLY( jmp_target[i] = bnum; ); 652 DEBUG_ONLY( jmp_rule[i] = mach->rule(); ); 653 } else { 654 // The jump distance is not short, try again during next iteration. 655 has_short_branch_candidate = true; 656 } 657 } // (mach->may_be_short_branch()) 658 if (mach != nullptr && (mach->may_be_short_branch() || 659 mach->avoid_back_to_back(MachNode::AVOID_AFTER))) { 660 last_may_be_short_branch_adr = blk_starts[i] + jmp_offset[i] + jmp_size[i]; 661 } 662 blk_starts[i+1] -= adjust_block_start; 663 } 664 } 665 666 #ifdef ASSERT 667 for (uint i = 0; i < nblocks; i++) { // For all blocks 668 if (jmp_target[i] != 0) { 669 int br_size = jmp_size[i]; 670 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_offset[i]); 671 if (!C->matcher()->is_short_branch_offset(jmp_rule[i], br_size, offset)) { 672 tty->print_cr("target (%d) - jmp_offset(%d) = offset (%d), jump_size(%d), jmp_block B%d, target_block B%d", blk_starts[jmp_target[i]], blk_starts[i] + jmp_offset[i], offset, br_size, i, jmp_target[i]); 673 } 674 assert(C->matcher()->is_short_branch_offset(jmp_rule[i], br_size, offset), "Displacement too large for short jmp"); 675 } 676 } 677 #endif 678 679 // Step 3, compute the offsets of all blocks, will be done in fill_buffer() 680 // after ScheduleAndBundle(). 681 682 // ------------------ 683 // Compute size for code buffer 684 code_size = blk_starts[nblocks]; 685 686 // Relocation records 687 reloc_size += 1; // Relo entry for exception handler 688 689 // Adjust reloc_size to number of record of relocation info 690 // Min is 2 bytes, max is probably 6 or 8, with a tax up to 25% for 691 // a relocation index. 692 // The CodeBuffer will expand the locs array if this estimate is too low. 693 reloc_size *= 10 / sizeof(relocInfo); 694 695 _buf_sizes._reloc = reloc_size; 696 _buf_sizes._code = code_size; 697 _buf_sizes._stub = stub_size; 698 } 699 700 //------------------------------FillLocArray----------------------------------- 701 // Create a bit of debug info and append it to the array. The mapping is from 702 // Java local or expression stack to constant, register or stack-slot. For 703 // doubles, insert 2 mappings and return 1 (to tell the caller that the next 704 // entry has been taken care of and caller should skip it). 705 static LocationValue *new_loc_value( PhaseRegAlloc *ra, OptoReg::Name regnum, Location::Type l_type ) { 706 // This should never have accepted Bad before 707 assert(OptoReg::is_valid(regnum), "location must be valid"); 708 return (OptoReg::is_reg(regnum)) 709 ? new LocationValue(Location::new_reg_loc(l_type, OptoReg::as_VMReg(regnum)) ) 710 : new LocationValue(Location::new_stk_loc(l_type, ra->reg2offset(regnum))); 711 } 712 713 714 ObjectValue* 715 PhaseOutput::sv_for_node_id(GrowableArray<ScopeValue*> *objs, int id) { 716 for (int i = 0; i < objs->length(); i++) { 717 assert(objs->at(i)->is_object(), "corrupt object cache"); 718 ObjectValue* sv = (ObjectValue*) objs->at(i); 719 if (sv->id() == id) { 720 return sv; 721 } 722 } 723 // Otherwise.. 724 return nullptr; 725 } 726 727 void PhaseOutput::set_sv_for_object_node(GrowableArray<ScopeValue*> *objs, 728 ObjectValue* sv ) { 729 assert(sv_for_node_id(objs, sv->id()) == nullptr, "Precondition"); 730 objs->append(sv); 731 } 732 733 734 void PhaseOutput::FillLocArray( int idx, MachSafePointNode* sfpt, Node *local, 735 GrowableArray<ScopeValue*> *array, 736 GrowableArray<ScopeValue*> *objs ) { 737 assert( local, "use _top instead of null" ); 738 if (array->length() != idx) { 739 assert(array->length() == idx + 1, "Unexpected array count"); 740 // Old functionality: 741 // return 742 // New functionality: 743 // Assert if the local is not top. In product mode let the new node 744 // override the old entry. 745 assert(local == C->top(), "LocArray collision"); 746 if (local == C->top()) { 747 return; 748 } 749 array->pop(); 750 } 751 const Type *t = local->bottom_type(); 752 753 // Is it a safepoint scalar object node? 754 if (local->is_SafePointScalarObject()) { 755 SafePointScalarObjectNode* spobj = local->as_SafePointScalarObject(); 756 757 ObjectValue* sv = (ObjectValue*) sv_for_node_id(objs, spobj->_idx); 758 if (sv == nullptr) { 759 ciKlass* cik = t->is_oopptr()->exact_klass(); 760 assert(cik->is_instance_klass() || 761 cik->is_array_klass(), "Not supported allocation."); 762 sv = new ObjectValue(spobj->_idx, 763 new ConstantOopWriteValue(cik->java_mirror()->constant_encoding())); 764 set_sv_for_object_node(objs, sv); 765 766 uint first_ind = spobj->first_index(sfpt->jvms()); 767 for (uint i = 0; i < spobj->n_fields(); i++) { 768 Node* fld_node = sfpt->in(first_ind+i); 769 (void)FillLocArray(sv->field_values()->length(), sfpt, fld_node, sv->field_values(), objs); 770 } 771 } 772 array->append(sv); 773 return; 774 } else if (local->is_SafePointScalarMerge()) { 775 SafePointScalarMergeNode* smerge = local->as_SafePointScalarMerge(); 776 ObjectMergeValue* mv = (ObjectMergeValue*) sv_for_node_id(objs, smerge->_idx); 777 778 if (mv == nullptr) { 779 GrowableArray<ScopeValue*> deps; 780 781 int merge_pointer_idx = smerge->merge_pointer_idx(sfpt->jvms()); 782 (void)FillLocArray(0, sfpt, sfpt->in(merge_pointer_idx), &deps, objs); 783 assert(deps.length() == 1, "missing value"); 784 785 int selector_idx = smerge->selector_idx(sfpt->jvms()); 786 (void)FillLocArray(1, nullptr, sfpt->in(selector_idx), &deps, nullptr); 787 assert(deps.length() == 2, "missing value"); 788 789 mv = new ObjectMergeValue(smerge->_idx, deps.at(0), deps.at(1)); 790 set_sv_for_object_node(objs, mv); 791 792 for (uint i = 1; i < smerge->req(); i++) { 793 Node* obj_node = smerge->in(i); 794 (void)FillLocArray(mv->possible_objects()->length(), sfpt, obj_node, mv->possible_objects(), objs); 795 } 796 } 797 array->append(mv); 798 return; 799 } 800 801 // Grab the register number for the local 802 OptoReg::Name regnum = C->regalloc()->get_reg_first(local); 803 if( OptoReg::is_valid(regnum) ) {// Got a register/stack? 804 // Record the double as two float registers. 805 // The register mask for such a value always specifies two adjacent 806 // float registers, with the lower register number even. 807 // Normally, the allocation of high and low words to these registers 808 // is irrelevant, because nearly all operations on register pairs 809 // (e.g., StoreD) treat them as a single unit. 810 // Here, we assume in addition that the words in these two registers 811 // stored "naturally" (by operations like StoreD and double stores 812 // within the interpreter) such that the lower-numbered register 813 // is written to the lower memory address. This may seem like 814 // a machine dependency, but it is not--it is a requirement on 815 // the author of the <arch>.ad file to ensure that, for every 816 // even/odd double-register pair to which a double may be allocated, 817 // the word in the even single-register is stored to the first 818 // memory word. (Note that register numbers are completely 819 // arbitrary, and are not tied to any machine-level encodings.) 820 #ifdef _LP64 821 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon ) { 822 array->append(new ConstantIntValue((jint)0)); 823 array->append(new_loc_value( C->regalloc(), regnum, Location::dbl )); 824 } else if ( t->base() == Type::Long ) { 825 array->append(new ConstantIntValue((jint)0)); 826 array->append(new_loc_value( C->regalloc(), regnum, Location::lng )); 827 } else if ( t->base() == Type::RawPtr ) { 828 // jsr/ret return address which must be restored into the full 829 // width 64-bit stack slot. 830 array->append(new_loc_value( C->regalloc(), regnum, Location::lng )); 831 } 832 #else //_LP64 833 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon || t->base() == Type::Long ) { 834 // Repack the double/long as two jints. 835 // The convention the interpreter uses is that the second local 836 // holds the first raw word of the native double representation. 837 // This is actually reasonable, since locals and stack arrays 838 // grow downwards in all implementations. 839 // (If, on some machine, the interpreter's Java locals or stack 840 // were to grow upwards, the embedded doubles would be word-swapped.) 841 array->append(new_loc_value( C->regalloc(), OptoReg::add(regnum,1), Location::normal )); 842 array->append(new_loc_value( C->regalloc(), regnum , Location::normal )); 843 } 844 #endif //_LP64 845 else if( (t->base() == Type::FloatBot || t->base() == Type::FloatCon) && 846 OptoReg::is_reg(regnum) ) { 847 array->append(new_loc_value( C->regalloc(), regnum, Matcher::float_in_double() 848 ? Location::float_in_dbl : Location::normal )); 849 } else if( t->base() == Type::Int && OptoReg::is_reg(regnum) ) { 850 array->append(new_loc_value( C->regalloc(), regnum, Matcher::int_in_long 851 ? Location::int_in_long : Location::normal )); 852 } else if( t->base() == Type::NarrowOop ) { 853 array->append(new_loc_value( C->regalloc(), regnum, Location::narrowoop )); 854 } else if (t->base() == Type::VectorA || t->base() == Type::VectorS || 855 t->base() == Type::VectorD || t->base() == Type::VectorX || 856 t->base() == Type::VectorY || t->base() == Type::VectorZ) { 857 array->append(new_loc_value( C->regalloc(), regnum, Location::vector )); 858 } else if (C->regalloc()->is_oop(local)) { 859 assert(t->base() == Type::OopPtr || t->base() == Type::InstPtr || 860 t->base() == Type::AryPtr, 861 "Unexpected type: %s", t->msg()); 862 array->append(new_loc_value( C->regalloc(), regnum, Location::oop )); 863 } else { 864 assert(t->base() == Type::Int || t->base() == Type::Half || 865 t->base() == Type::FloatCon || t->base() == Type::FloatBot, 866 "Unexpected type: %s", t->msg()); 867 array->append(new_loc_value( C->regalloc(), regnum, Location::normal )); 868 } 869 return; 870 } 871 872 // No register. It must be constant data. 873 switch (t->base()) { 874 case Type::Half: // Second half of a double 875 ShouldNotReachHere(); // Caller should skip 2nd halves 876 break; 877 case Type::AnyPtr: 878 array->append(new ConstantOopWriteValue(nullptr)); 879 break; 880 case Type::AryPtr: 881 case Type::InstPtr: // fall through 882 array->append(new ConstantOopWriteValue(t->isa_oopptr()->const_oop()->constant_encoding())); 883 break; 884 case Type::NarrowOop: 885 if (t == TypeNarrowOop::NULL_PTR) { 886 array->append(new ConstantOopWriteValue(nullptr)); 887 } else { 888 array->append(new ConstantOopWriteValue(t->make_ptr()->isa_oopptr()->const_oop()->constant_encoding())); 889 } 890 break; 891 case Type::Int: 892 array->append(new ConstantIntValue(t->is_int()->get_con())); 893 break; 894 case Type::RawPtr: 895 // A return address (T_ADDRESS). 896 assert((intptr_t)t->is_ptr()->get_con() < (intptr_t)0x10000, "must be a valid BCI"); 897 #ifdef _LP64 898 // Must be restored to the full-width 64-bit stack slot. 899 array->append(new ConstantLongValue(t->is_ptr()->get_con())); 900 #else 901 array->append(new ConstantIntValue(t->is_ptr()->get_con())); 902 #endif 903 break; 904 case Type::FloatCon: { 905 float f = t->is_float_constant()->getf(); 906 array->append(new ConstantIntValue(jint_cast(f))); 907 break; 908 } 909 case Type::DoubleCon: { 910 jdouble d = t->is_double_constant()->getd(); 911 #ifdef _LP64 912 array->append(new ConstantIntValue((jint)0)); 913 array->append(new ConstantDoubleValue(d)); 914 #else 915 // Repack the double as two jints. 916 // The convention the interpreter uses is that the second local 917 // holds the first raw word of the native double representation. 918 // This is actually reasonable, since locals and stack arrays 919 // grow downwards in all implementations. 920 // (If, on some machine, the interpreter's Java locals or stack 921 // were to grow upwards, the embedded doubles would be word-swapped.) 922 jlong_accessor acc; 923 acc.long_value = jlong_cast(d); 924 array->append(new ConstantIntValue(acc.words[1])); 925 array->append(new ConstantIntValue(acc.words[0])); 926 #endif 927 break; 928 } 929 case Type::Long: { 930 jlong d = t->is_long()->get_con(); 931 #ifdef _LP64 932 array->append(new ConstantIntValue((jint)0)); 933 array->append(new ConstantLongValue(d)); 934 #else 935 // Repack the long as two jints. 936 // The convention the interpreter uses is that the second local 937 // holds the first raw word of the native double representation. 938 // This is actually reasonable, since locals and stack arrays 939 // grow downwards in all implementations. 940 // (If, on some machine, the interpreter's Java locals or stack 941 // were to grow upwards, the embedded doubles would be word-swapped.) 942 jlong_accessor acc; 943 acc.long_value = d; 944 array->append(new ConstantIntValue(acc.words[1])); 945 array->append(new ConstantIntValue(acc.words[0])); 946 #endif 947 break; 948 } 949 case Type::Top: // Add an illegal value here 950 array->append(new LocationValue(Location())); 951 break; 952 default: 953 ShouldNotReachHere(); 954 break; 955 } 956 } 957 958 // Determine if this node starts a bundle 959 bool PhaseOutput::starts_bundle(const Node *n) const { 960 return (_node_bundling_limit > n->_idx && 961 _node_bundling_base[n->_idx].starts_bundle()); 962 } 963 964 // Determine if there is a monitor that has 'ov' as its owner. 965 bool PhaseOutput::contains_as_owner(GrowableArray<MonitorValue*> *monarray, ObjectValue *ov) const { 966 for (int k = 0; k < monarray->length(); k++) { 967 MonitorValue* mv = monarray->at(k); 968 if (mv->owner() == ov) { 969 return true; 970 } 971 } 972 973 return false; 974 } 975 976 //--------------------------Process_OopMap_Node-------------------------------- 977 void PhaseOutput::Process_OopMap_Node(MachNode *mach, int current_offset) { 978 // Handle special safepoint nodes for synchronization 979 MachSafePointNode *sfn = mach->as_MachSafePoint(); 980 MachCallNode *mcall; 981 982 int safepoint_pc_offset = current_offset; 983 bool is_method_handle_invoke = false; 984 bool return_oop = false; 985 bool has_ea_local_in_scope = sfn->_has_ea_local_in_scope; 986 bool arg_escape = false; 987 988 // Add the safepoint in the DebugInfoRecorder 989 if( !mach->is_MachCall() ) { 990 mcall = nullptr; 991 C->debug_info()->add_safepoint(safepoint_pc_offset, sfn->_oop_map); 992 } else { 993 mcall = mach->as_MachCall(); 994 995 // Is the call a MethodHandle call? 996 if (mcall->is_MachCallJava()) { 997 if (mcall->as_MachCallJava()->_method_handle_invoke) { 998 assert(C->has_method_handle_invokes(), "must have been set during call generation"); 999 is_method_handle_invoke = true; 1000 } 1001 arg_escape = mcall->as_MachCallJava()->_arg_escape; 1002 } 1003 1004 // Check if a call returns an object. 1005 if (mcall->returns_pointer()) { 1006 return_oop = true; 1007 } 1008 safepoint_pc_offset += mcall->ret_addr_offset(); 1009 C->debug_info()->add_safepoint(safepoint_pc_offset, mcall->_oop_map); 1010 } 1011 1012 // Loop over the JVMState list to add scope information 1013 // Do not skip safepoints with a null method, they need monitor info 1014 JVMState* youngest_jvms = sfn->jvms(); 1015 int max_depth = youngest_jvms->depth(); 1016 1017 // Allocate the object pool for scalar-replaced objects -- the map from 1018 // small-integer keys (which can be recorded in the local and ostack 1019 // arrays) to descriptions of the object state. 1020 GrowableArray<ScopeValue*> *objs = new GrowableArray<ScopeValue*>(); 1021 1022 // Visit scopes from oldest to youngest. 1023 for (int depth = 1; depth <= max_depth; depth++) { 1024 JVMState* jvms = youngest_jvms->of_depth(depth); 1025 int idx; 1026 ciMethod* method = jvms->has_method() ? jvms->method() : nullptr; 1027 // Safepoints that do not have method() set only provide oop-map and monitor info 1028 // to support GC; these do not support deoptimization. 1029 int num_locs = (method == nullptr) ? 0 : jvms->loc_size(); 1030 int num_exps = (method == nullptr) ? 0 : jvms->stk_size(); 1031 int num_mon = jvms->nof_monitors(); 1032 assert(method == nullptr || jvms->bci() < 0 || num_locs == method->max_locals(), 1033 "JVMS local count must match that of the method"); 1034 1035 // Add Local and Expression Stack Information 1036 1037 // Insert locals into the locarray 1038 GrowableArray<ScopeValue*> *locarray = new GrowableArray<ScopeValue*>(num_locs); 1039 for( idx = 0; idx < num_locs; idx++ ) { 1040 FillLocArray( idx, sfn, sfn->local(jvms, idx), locarray, objs ); 1041 } 1042 1043 // Insert expression stack entries into the exparray 1044 GrowableArray<ScopeValue*> *exparray = new GrowableArray<ScopeValue*>(num_exps); 1045 for( idx = 0; idx < num_exps; idx++ ) { 1046 FillLocArray( idx, sfn, sfn->stack(jvms, idx), exparray, objs ); 1047 } 1048 1049 // Add in mappings of the monitors 1050 assert( !method || 1051 !method->is_synchronized() || 1052 method->is_native() || 1053 num_mon > 0 || 1054 !GenerateSynchronizationCode, 1055 "monitors must always exist for synchronized methods"); 1056 1057 // Build the growable array of ScopeValues for exp stack 1058 GrowableArray<MonitorValue*> *monarray = new GrowableArray<MonitorValue*>(num_mon); 1059 1060 // Loop over monitors and insert into array 1061 for (idx = 0; idx < num_mon; idx++) { 1062 // Grab the node that defines this monitor 1063 Node* box_node = sfn->monitor_box(jvms, idx); 1064 Node* obj_node = sfn->monitor_obj(jvms, idx); 1065 1066 // Create ScopeValue for object 1067 ScopeValue *scval = nullptr; 1068 1069 if (obj_node->is_SafePointScalarObject()) { 1070 SafePointScalarObjectNode* spobj = obj_node->as_SafePointScalarObject(); 1071 scval = PhaseOutput::sv_for_node_id(objs, spobj->_idx); 1072 if (scval == nullptr) { 1073 const Type *t = spobj->bottom_type(); 1074 ciKlass* cik = t->is_oopptr()->exact_klass(); 1075 assert(cik->is_instance_klass() || 1076 cik->is_array_klass(), "Not supported allocation."); 1077 ObjectValue* sv = new ObjectValue(spobj->_idx, 1078 new ConstantOopWriteValue(cik->java_mirror()->constant_encoding())); 1079 PhaseOutput::set_sv_for_object_node(objs, sv); 1080 1081 uint first_ind = spobj->first_index(youngest_jvms); 1082 for (uint i = 0; i < spobj->n_fields(); i++) { 1083 Node* fld_node = sfn->in(first_ind+i); 1084 (void)FillLocArray(sv->field_values()->length(), sfn, fld_node, sv->field_values(), objs); 1085 } 1086 scval = sv; 1087 } 1088 } else if (obj_node->is_SafePointScalarMerge()) { 1089 SafePointScalarMergeNode* smerge = obj_node->as_SafePointScalarMerge(); 1090 ObjectMergeValue* mv = (ObjectMergeValue*) sv_for_node_id(objs, smerge->_idx); 1091 1092 if (mv == nullptr) { 1093 GrowableArray<ScopeValue*> deps; 1094 1095 int merge_pointer_idx = smerge->merge_pointer_idx(youngest_jvms); 1096 FillLocArray(0, sfn, sfn->in(merge_pointer_idx), &deps, objs); 1097 assert(deps.length() == 1, "missing value"); 1098 1099 int selector_idx = smerge->selector_idx(youngest_jvms); 1100 FillLocArray(1, nullptr, sfn->in(selector_idx), &deps, nullptr); 1101 assert(deps.length() == 2, "missing value"); 1102 1103 mv = new ObjectMergeValue(smerge->_idx, deps.at(0), deps.at(1)); 1104 set_sv_for_object_node(objs, mv); 1105 1106 for (uint i = 1; i < smerge->req(); i++) { 1107 Node* obj_node = smerge->in(i); 1108 FillLocArray(mv->possible_objects()->length(), sfn, obj_node, mv->possible_objects(), objs); 1109 } 1110 } 1111 scval = mv; 1112 } else if (!obj_node->is_Con()) { 1113 OptoReg::Name obj_reg = C->regalloc()->get_reg_first(obj_node); 1114 if( obj_node->bottom_type()->base() == Type::NarrowOop ) { 1115 scval = new_loc_value( C->regalloc(), obj_reg, Location::narrowoop ); 1116 } else { 1117 scval = new_loc_value( C->regalloc(), obj_reg, Location::oop ); 1118 } 1119 } else { 1120 const TypePtr *tp = obj_node->get_ptr_type(); 1121 scval = new ConstantOopWriteValue(tp->is_oopptr()->const_oop()->constant_encoding()); 1122 } 1123 1124 OptoReg::Name box_reg = BoxLockNode::reg(box_node); 1125 Location basic_lock = Location::new_stk_loc(Location::normal,C->regalloc()->reg2offset(box_reg)); 1126 bool eliminated = (box_node->is_BoxLock() && box_node->as_BoxLock()->is_eliminated()); 1127 monarray->append(new MonitorValue(scval, basic_lock, eliminated)); 1128 } 1129 1130 // Mark ObjectValue nodes as root nodes if they are directly 1131 // referenced in the JVMS. 1132 for (int i = 0; i < objs->length(); i++) { 1133 ScopeValue* sv = objs->at(i); 1134 if (sv->is_object_merge()) { 1135 ObjectMergeValue* merge = sv->as_ObjectMergeValue(); 1136 1137 for (int j = 0; j< merge->possible_objects()->length(); j++) { 1138 ObjectValue* ov = merge->possible_objects()->at(j)->as_ObjectValue(); 1139 bool is_root = locarray->contains(ov) || exparray->contains(ov) || contains_as_owner(monarray, ov); 1140 ov->set_root(is_root); 1141 } 1142 } 1143 } 1144 1145 // We dump the object pool first, since deoptimization reads it in first. 1146 C->debug_info()->dump_object_pool(objs); 1147 1148 // Build first class objects to pass to scope 1149 DebugToken *locvals = C->debug_info()->create_scope_values(locarray); 1150 DebugToken *expvals = C->debug_info()->create_scope_values(exparray); 1151 DebugToken *monvals = C->debug_info()->create_monitor_values(monarray); 1152 1153 // Make method available for all Safepoints 1154 ciMethod* scope_method = method ? method : C->method(); 1155 // Describe the scope here 1156 assert(jvms->bci() >= InvocationEntryBci && jvms->bci() <= 0x10000, "must be a valid or entry BCI"); 1157 assert(!jvms->should_reexecute() || depth == max_depth, "reexecute allowed only for the youngest"); 1158 // Now we can describe the scope. 1159 methodHandle null_mh; 1160 bool rethrow_exception = false; 1161 C->debug_info()->describe_scope( 1162 safepoint_pc_offset, 1163 null_mh, 1164 scope_method, 1165 jvms->bci(), 1166 jvms->should_reexecute(), 1167 rethrow_exception, 1168 is_method_handle_invoke, 1169 return_oop, 1170 has_ea_local_in_scope, 1171 arg_escape, 1172 locvals, 1173 expvals, 1174 monvals 1175 ); 1176 } // End jvms loop 1177 1178 // Mark the end of the scope set. 1179 C->debug_info()->end_safepoint(safepoint_pc_offset); 1180 } 1181 1182 1183 1184 // A simplified version of Process_OopMap_Node, to handle non-safepoints. 1185 class NonSafepointEmitter { 1186 Compile* C; 1187 JVMState* _pending_jvms; 1188 int _pending_offset; 1189 1190 void emit_non_safepoint(); 1191 1192 public: 1193 NonSafepointEmitter(Compile* compile) { 1194 this->C = compile; 1195 _pending_jvms = nullptr; 1196 _pending_offset = 0; 1197 } 1198 1199 void observe_instruction(Node* n, int pc_offset) { 1200 if (!C->debug_info()->recording_non_safepoints()) return; 1201 1202 Node_Notes* nn = C->node_notes_at(n->_idx); 1203 if (nn == nullptr || nn->jvms() == nullptr) return; 1204 if (_pending_jvms != nullptr && 1205 _pending_jvms->same_calls_as(nn->jvms())) { 1206 // Repeated JVMS? Stretch it up here. 1207 _pending_offset = pc_offset; 1208 } else { 1209 if (_pending_jvms != nullptr && 1210 _pending_offset < pc_offset) { 1211 emit_non_safepoint(); 1212 } 1213 _pending_jvms = nullptr; 1214 if (pc_offset > C->debug_info()->last_pc_offset()) { 1215 // This is the only way _pending_jvms can become non-null: 1216 _pending_jvms = nn->jvms(); 1217 _pending_offset = pc_offset; 1218 } 1219 } 1220 } 1221 1222 // Stay out of the way of real safepoints: 1223 void observe_safepoint(JVMState* jvms, int pc_offset) { 1224 if (_pending_jvms != nullptr && 1225 !_pending_jvms->same_calls_as(jvms) && 1226 _pending_offset < pc_offset) { 1227 emit_non_safepoint(); 1228 } 1229 _pending_jvms = nullptr; 1230 } 1231 1232 void flush_at_end() { 1233 if (_pending_jvms != nullptr) { 1234 emit_non_safepoint(); 1235 } 1236 _pending_jvms = nullptr; 1237 } 1238 }; 1239 1240 void NonSafepointEmitter::emit_non_safepoint() { 1241 JVMState* youngest_jvms = _pending_jvms; 1242 int pc_offset = _pending_offset; 1243 1244 // Clear it now: 1245 _pending_jvms = nullptr; 1246 1247 DebugInformationRecorder* debug_info = C->debug_info(); 1248 assert(debug_info->recording_non_safepoints(), "sanity"); 1249 1250 debug_info->add_non_safepoint(pc_offset); 1251 int max_depth = youngest_jvms->depth(); 1252 1253 // Visit scopes from oldest to youngest. 1254 for (int depth = 1; depth <= max_depth; depth++) { 1255 JVMState* jvms = youngest_jvms->of_depth(depth); 1256 ciMethod* method = jvms->has_method() ? jvms->method() : nullptr; 1257 assert(!jvms->should_reexecute() || depth==max_depth, "reexecute allowed only for the youngest"); 1258 methodHandle null_mh; 1259 debug_info->describe_scope(pc_offset, null_mh, method, jvms->bci(), jvms->should_reexecute()); 1260 } 1261 1262 // Mark the end of the scope set. 1263 debug_info->end_non_safepoint(pc_offset); 1264 } 1265 1266 //------------------------------init_buffer------------------------------------ 1267 void PhaseOutput::estimate_buffer_size(int& const_req) { 1268 1269 // Set the initially allocated size 1270 const_req = initial_const_capacity; 1271 1272 // The extra spacing after the code is necessary on some platforms. 1273 // Sometimes we need to patch in a jump after the last instruction, 1274 // if the nmethod has been deoptimized. (See 4932387, 4894843.) 1275 1276 // Compute the byte offset where we can store the deopt pc. 1277 if (C->fixed_slots() != 0) { 1278 _orig_pc_slot_offset_in_bytes = C->regalloc()->reg2offset(OptoReg::stack2reg(_orig_pc_slot)); 1279 } 1280 1281 // Compute prolog code size 1282 _method_size = 0; 1283 _frame_slots = OptoReg::reg2stack(C->matcher()->_old_SP) + C->regalloc()->_framesize; 1284 assert(_frame_slots >= 0 && _frame_slots < 1000000, "sanity check"); 1285 1286 if (C->has_mach_constant_base_node()) { 1287 uint add_size = 0; 1288 // Fill the constant table. 1289 // Note: This must happen before shorten_branches. 1290 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) { 1291 Block* b = C->cfg()->get_block(i); 1292 1293 for (uint j = 0; j < b->number_of_nodes(); j++) { 1294 Node* n = b->get_node(j); 1295 1296 // If the node is a MachConstantNode evaluate the constant 1297 // value section. 1298 if (n->is_MachConstant()) { 1299 MachConstantNode* machcon = n->as_MachConstant(); 1300 machcon->eval_constant(C); 1301 } else if (n->is_Mach()) { 1302 // On Power there are more nodes that issue constants. 1303 add_size += (n->as_Mach()->ins_num_consts() * 8); 1304 } 1305 } 1306 } 1307 1308 // Calculate the offsets of the constants and the size of the 1309 // constant table (including the padding to the next section). 1310 constant_table().calculate_offsets_and_size(); 1311 const_req = constant_table().size() + add_size; 1312 } 1313 1314 // Initialize the space for the BufferBlob used to find and verify 1315 // instruction size in MachNode::emit_size() 1316 init_scratch_buffer_blob(const_req); 1317 } 1318 1319 CodeBuffer* PhaseOutput::init_buffer() { 1320 int stub_req = _buf_sizes._stub; 1321 int code_req = _buf_sizes._code; 1322 int const_req = _buf_sizes._const; 1323 1324 int pad_req = NativeCall::instruction_size; 1325 1326 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 1327 stub_req += bs->estimate_stub_size(); 1328 1329 // nmethod and CodeBuffer count stubs & constants as part of method's code. 1330 // class HandlerImpl is platform-specific and defined in the *.ad files. 1331 int exception_handler_req = HandlerImpl::size_exception_handler() + MAX_stubs_size; // add marginal slop for handler 1332 int deopt_handler_req = HandlerImpl::size_deopt_handler() + MAX_stubs_size; // add marginal slop for handler 1333 stub_req += MAX_stubs_size; // ensure per-stub margin 1334 code_req += MAX_inst_size; // ensure per-instruction margin 1335 1336 if (StressCodeBuffers) 1337 code_req = const_req = stub_req = exception_handler_req = deopt_handler_req = 0x10; // force expansion 1338 1339 int total_req = 1340 const_req + 1341 code_req + 1342 pad_req + 1343 stub_req + 1344 exception_handler_req + 1345 deopt_handler_req; // deopt handler 1346 1347 if (C->has_method_handle_invokes()) 1348 total_req += deopt_handler_req; // deopt MH handler 1349 1350 CodeBuffer* cb = code_buffer(); 1351 cb->initialize(total_req, _buf_sizes._reloc); 1352 1353 // Have we run out of code space? 1354 if ((cb->blob() == nullptr) || (!CompileBroker::should_compile_new_jobs())) { 1355 C->record_failure("CodeCache is full"); 1356 return nullptr; 1357 } 1358 // Configure the code buffer. 1359 cb->initialize_consts_size(const_req); 1360 cb->initialize_stubs_size(stub_req); 1361 cb->initialize_oop_recorder(C->env()->oop_recorder()); 1362 1363 // fill in the nop array for bundling computations 1364 MachNode *_nop_list[Bundle::_nop_count]; 1365 Bundle::initialize_nops(_nop_list); 1366 1367 return cb; 1368 } 1369 1370 //------------------------------fill_buffer------------------------------------ 1371 void PhaseOutput::fill_buffer(CodeBuffer* cb, uint* blk_starts) { 1372 // blk_starts[] contains offsets calculated during short branches processing, 1373 // offsets should not be increased during following steps. 1374 1375 // Compute the size of first NumberOfLoopInstrToAlign instructions at head 1376 // of a loop. It is used to determine the padding for loop alignment. 1377 Compile::TracePhase tp("fill buffer", &timers[_t_fillBuffer]); 1378 1379 compute_loop_first_inst_sizes(); 1380 1381 // Create oopmap set. 1382 _oop_map_set = new OopMapSet(); 1383 1384 // !!!!! This preserves old handling of oopmaps for now 1385 C->debug_info()->set_oopmaps(_oop_map_set); 1386 1387 uint nblocks = C->cfg()->number_of_blocks(); 1388 // Count and start of implicit null check instructions 1389 uint inct_cnt = 0; 1390 uint* inct_starts = NEW_RESOURCE_ARRAY(uint, nblocks+1); 1391 1392 // Count and start of calls 1393 uint* call_returns = NEW_RESOURCE_ARRAY(uint, nblocks+1); 1394 1395 uint return_offset = 0; 1396 int nop_size = (new MachNopNode())->size(C->regalloc()); 1397 1398 int previous_offset = 0; 1399 int current_offset = 0; 1400 int last_call_offset = -1; 1401 int last_avoid_back_to_back_offset = -1; 1402 #ifdef ASSERT 1403 uint* jmp_target = NEW_RESOURCE_ARRAY(uint,nblocks); 1404 uint* jmp_offset = NEW_RESOURCE_ARRAY(uint,nblocks); 1405 uint* jmp_size = NEW_RESOURCE_ARRAY(uint,nblocks); 1406 uint* jmp_rule = NEW_RESOURCE_ARRAY(uint,nblocks); 1407 #endif 1408 1409 // Create an array of unused labels, one for each basic block, if printing is enabled 1410 #if defined(SUPPORT_OPTO_ASSEMBLY) 1411 int* node_offsets = nullptr; 1412 uint node_offset_limit = C->unique(); 1413 1414 if (C->print_assembly()) { 1415 node_offsets = NEW_RESOURCE_ARRAY(int, node_offset_limit); 1416 } 1417 if (node_offsets != nullptr) { 1418 // We need to initialize. Unused array elements may contain garbage and mess up PrintOptoAssembly. 1419 memset(node_offsets, 0, node_offset_limit*sizeof(int)); 1420 } 1421 #endif 1422 1423 NonSafepointEmitter non_safepoints(C); // emit non-safepoints lazily 1424 1425 // Emit the constant table. 1426 if (C->has_mach_constant_base_node()) { 1427 if (!constant_table().emit(*cb)) { 1428 C->record_failure("consts section overflow"); 1429 return; 1430 } 1431 } 1432 1433 // Create an array of labels, one for each basic block 1434 Label* blk_labels = NEW_RESOURCE_ARRAY(Label, nblocks+1); 1435 for (uint i = 0; i <= nblocks; i++) { 1436 blk_labels[i].init(); 1437 } 1438 1439 // Now fill in the code buffer 1440 Node* delay_slot = nullptr; 1441 for (uint i = 0; i < nblocks; i++) { 1442 Block* block = C->cfg()->get_block(i); 1443 _block = block; 1444 Node* head = block->head(); 1445 1446 // If this block needs to start aligned (i.e, can be reached other 1447 // than by falling-thru from the previous block), then force the 1448 // start of a new bundle. 1449 if (Pipeline::requires_bundling() && starts_bundle(head)) { 1450 cb->flush_bundle(true); 1451 } 1452 1453 #ifdef ASSERT 1454 if (!block->is_connector()) { 1455 stringStream st; 1456 block->dump_head(C->cfg(), &st); 1457 MacroAssembler(cb).block_comment(st.freeze()); 1458 } 1459 jmp_target[i] = 0; 1460 jmp_offset[i] = 0; 1461 jmp_size[i] = 0; 1462 jmp_rule[i] = 0; 1463 #endif 1464 int blk_offset = current_offset; 1465 1466 // Define the label at the beginning of the basic block 1467 MacroAssembler(cb).bind(blk_labels[block->_pre_order]); 1468 1469 uint last_inst = block->number_of_nodes(); 1470 1471 // Emit block normally, except for last instruction. 1472 // Emit means "dump code bits into code buffer". 1473 for (uint j = 0; j<last_inst; j++) { 1474 _index = j; 1475 1476 // Get the node 1477 Node* n = block->get_node(j); 1478 1479 // See if delay slots are supported 1480 if (valid_bundle_info(n) && node_bundling(n)->used_in_unconditional_delay()) { 1481 assert(delay_slot == nullptr, "no use of delay slot node"); 1482 assert(n->size(C->regalloc()) == Pipeline::instr_unit_size(), "delay slot instruction wrong size"); 1483 1484 delay_slot = n; 1485 continue; 1486 } 1487 1488 // If this starts a new instruction group, then flush the current one 1489 // (but allow split bundles) 1490 if (Pipeline::requires_bundling() && starts_bundle(n)) 1491 cb->flush_bundle(false); 1492 1493 // Special handling for SafePoint/Call Nodes 1494 bool is_mcall = false; 1495 if (n->is_Mach()) { 1496 MachNode *mach = n->as_Mach(); 1497 is_mcall = n->is_MachCall(); 1498 bool is_sfn = n->is_MachSafePoint(); 1499 1500 // If this requires all previous instructions be flushed, then do so 1501 if (is_sfn || is_mcall || mach->alignment_required() != 1) { 1502 cb->flush_bundle(true); 1503 current_offset = cb->insts_size(); 1504 } 1505 1506 // A padding may be needed again since a previous instruction 1507 // could be moved to delay slot. 1508 1509 // align the instruction if necessary 1510 int padding = mach->compute_padding(current_offset); 1511 // Make sure safepoint node for polling is distinct from a call's 1512 // return by adding a nop if needed. 1513 if (is_sfn && !is_mcall && padding == 0 && current_offset == last_call_offset) { 1514 padding = nop_size; 1515 } 1516 if (padding == 0 && mach->avoid_back_to_back(MachNode::AVOID_BEFORE) && 1517 current_offset == last_avoid_back_to_back_offset) { 1518 // Avoid back to back some instructions. 1519 padding = nop_size; 1520 } 1521 1522 if (padding > 0) { 1523 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size"); 1524 int nops_cnt = padding / nop_size; 1525 MachNode *nop = new MachNopNode(nops_cnt); 1526 block->insert_node(nop, j++); 1527 last_inst++; 1528 C->cfg()->map_node_to_block(nop, block); 1529 // Ensure enough space. 1530 cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size); 1531 if ((cb->blob() == nullptr) || (!CompileBroker::should_compile_new_jobs())) { 1532 C->record_failure("CodeCache is full"); 1533 return; 1534 } 1535 nop->emit(*cb, C->regalloc()); 1536 cb->flush_bundle(true); 1537 current_offset = cb->insts_size(); 1538 } 1539 1540 bool observe_safepoint = is_sfn; 1541 // Remember the start of the last call in a basic block 1542 if (is_mcall) { 1543 MachCallNode *mcall = mach->as_MachCall(); 1544 1545 // This destination address is NOT PC-relative 1546 mcall->method_set((intptr_t)mcall->entry_point()); 1547 1548 // Save the return address 1549 call_returns[block->_pre_order] = current_offset + mcall->ret_addr_offset(); 1550 1551 observe_safepoint = mcall->guaranteed_safepoint(); 1552 } 1553 1554 // sfn will be valid whenever mcall is valid now because of inheritance 1555 if (observe_safepoint) { 1556 // Handle special safepoint nodes for synchronization 1557 if (!is_mcall) { 1558 MachSafePointNode *sfn = mach->as_MachSafePoint(); 1559 // !!!!! Stubs only need an oopmap right now, so bail out 1560 if (sfn->jvms()->method() == nullptr) { 1561 // Write the oopmap directly to the code blob??!! 1562 continue; 1563 } 1564 } // End synchronization 1565 1566 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(), 1567 current_offset); 1568 Process_OopMap_Node(mach, current_offset); 1569 } // End if safepoint 1570 1571 // If this is a null check, then add the start of the previous instruction to the list 1572 else if( mach->is_MachNullCheck() ) { 1573 inct_starts[inct_cnt++] = previous_offset; 1574 } 1575 1576 // If this is a branch, then fill in the label with the target BB's label 1577 else if (mach->is_MachBranch()) { 1578 // This requires the TRUE branch target be in succs[0] 1579 uint block_num = block->non_connector_successor(0)->_pre_order; 1580 1581 // Try to replace long branch if delay slot is not used, 1582 // it is mostly for back branches since forward branch's 1583 // distance is not updated yet. 1584 bool delay_slot_is_used = valid_bundle_info(n) && 1585 C->output()->node_bundling(n)->use_unconditional_delay(); 1586 if (!delay_slot_is_used && mach->may_be_short_branch()) { 1587 assert(delay_slot == nullptr, "not expecting delay slot node"); 1588 int br_size = n->size(C->regalloc()); 1589 int offset = blk_starts[block_num] - current_offset; 1590 if (block_num >= i) { 1591 // Current and following block's offset are not 1592 // finalized yet, adjust distance by the difference 1593 // between calculated and final offsets of current block. 1594 offset -= (blk_starts[i] - blk_offset); 1595 } 1596 // In the following code a nop could be inserted before 1597 // the branch which will increase the backward distance. 1598 bool needs_padding = (current_offset == last_avoid_back_to_back_offset); 1599 if (needs_padding && offset <= 0) 1600 offset -= nop_size; 1601 1602 if (C->matcher()->is_short_branch_offset(mach->rule(), br_size, offset)) { 1603 // We've got a winner. Replace this branch. 1604 MachNode* replacement = mach->as_MachBranch()->short_branch_version(); 1605 1606 // Update the jmp_size. 1607 int new_size = replacement->size(C->regalloc()); 1608 assert((br_size - new_size) >= (int)nop_size, "short_branch size should be smaller"); 1609 // Insert padding between avoid_back_to_back branches. 1610 if (needs_padding && replacement->avoid_back_to_back(MachNode::AVOID_BEFORE)) { 1611 MachNode *nop = new MachNopNode(); 1612 block->insert_node(nop, j++); 1613 C->cfg()->map_node_to_block(nop, block); 1614 last_inst++; 1615 nop->emit(*cb, C->regalloc()); 1616 cb->flush_bundle(true); 1617 current_offset = cb->insts_size(); 1618 } 1619 #ifdef ASSERT 1620 jmp_target[i] = block_num; 1621 jmp_offset[i] = current_offset - blk_offset; 1622 jmp_size[i] = new_size; 1623 jmp_rule[i] = mach->rule(); 1624 #endif 1625 block->map_node(replacement, j); 1626 mach->subsume_by(replacement, C); 1627 n = replacement; 1628 mach = replacement; 1629 } 1630 } 1631 mach->as_MachBranch()->label_set( &blk_labels[block_num], block_num ); 1632 } else if (mach->ideal_Opcode() == Op_Jump) { 1633 for (uint h = 0; h < block->_num_succs; h++) { 1634 Block* succs_block = block->_succs[h]; 1635 for (uint j = 1; j < succs_block->num_preds(); j++) { 1636 Node* jpn = succs_block->pred(j); 1637 if (jpn->is_JumpProj() && jpn->in(0) == mach) { 1638 uint block_num = succs_block->non_connector()->_pre_order; 1639 Label *blkLabel = &blk_labels[block_num]; 1640 mach->add_case_label(jpn->as_JumpProj()->proj_no(), blkLabel); 1641 } 1642 } 1643 } 1644 } 1645 #ifdef ASSERT 1646 // Check that oop-store precedes the card-mark 1647 else if (mach->ideal_Opcode() == Op_StoreCM) { 1648 uint storeCM_idx = j; 1649 int count = 0; 1650 for (uint prec = mach->req(); prec < mach->len(); prec++) { 1651 Node *oop_store = mach->in(prec); // Precedence edge 1652 if (oop_store == nullptr) continue; 1653 count++; 1654 uint i4; 1655 for (i4 = 0; i4 < last_inst; ++i4) { 1656 if (block->get_node(i4) == oop_store) { 1657 break; 1658 } 1659 } 1660 // Note: This test can provide a false failure if other precedence 1661 // edges have been added to the storeCMNode. 1662 assert(i4 == last_inst || i4 < storeCM_idx, "CM card-mark executes before oop-store"); 1663 } 1664 assert(count > 0, "storeCM expects at least one precedence edge"); 1665 } 1666 #endif 1667 else if (!n->is_Proj()) { 1668 // Remember the beginning of the previous instruction, in case 1669 // it's followed by a flag-kill and a null-check. Happens on 1670 // Intel all the time, with add-to-memory kind of opcodes. 1671 previous_offset = current_offset; 1672 } 1673 1674 // Not an else-if! 1675 // If this is a trap based cmp then add its offset to the list. 1676 if (mach->is_TrapBasedCheckNode()) { 1677 inct_starts[inct_cnt++] = current_offset; 1678 } 1679 } 1680 1681 // Verify that there is sufficient space remaining 1682 cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size); 1683 if ((cb->blob() == nullptr) || (!CompileBroker::should_compile_new_jobs())) { 1684 C->record_failure("CodeCache is full"); 1685 return; 1686 } 1687 1688 // Save the offset for the listing 1689 #if defined(SUPPORT_OPTO_ASSEMBLY) 1690 if ((node_offsets != nullptr) && (n->_idx < node_offset_limit)) { 1691 node_offsets[n->_idx] = cb->insts_size(); 1692 } 1693 #endif 1694 assert(!C->failing(), "Should not reach here if failing."); 1695 1696 // "Normal" instruction case 1697 DEBUG_ONLY(uint instr_offset = cb->insts_size()); 1698 n->emit(*cb, C->regalloc()); 1699 current_offset = cb->insts_size(); 1700 1701 // Above we only verified that there is enough space in the instruction section. 1702 // However, the instruction may emit stubs that cause code buffer expansion. 1703 // Bail out here if expansion failed due to a lack of code cache space. 1704 if (C->failing()) { 1705 return; 1706 } 1707 1708 assert(!is_mcall || (call_returns[block->_pre_order] <= (uint)current_offset), 1709 "ret_addr_offset() not within emitted code"); 1710 1711 #ifdef ASSERT 1712 uint n_size = n->size(C->regalloc()); 1713 if (n_size < (current_offset-instr_offset)) { 1714 MachNode* mach = n->as_Mach(); 1715 n->dump(); 1716 mach->dump_format(C->regalloc(), tty); 1717 tty->print_cr(" n_size (%d), current_offset (%d), instr_offset (%d)", n_size, current_offset, instr_offset); 1718 Disassembler::decode(cb->insts_begin() + instr_offset, cb->insts_begin() + current_offset + 1, tty); 1719 tty->print_cr(" ------------------- "); 1720 BufferBlob* blob = this->scratch_buffer_blob(); 1721 address blob_begin = blob->content_begin(); 1722 Disassembler::decode(blob_begin, blob_begin + n_size + 1, tty); 1723 assert(false, "wrong size of mach node"); 1724 } 1725 #endif 1726 non_safepoints.observe_instruction(n, current_offset); 1727 1728 // mcall is last "call" that can be a safepoint 1729 // record it so we can see if a poll will directly follow it 1730 // in which case we'll need a pad to make the PcDesc sites unique 1731 // see 5010568. This can be slightly inaccurate but conservative 1732 // in the case that return address is not actually at current_offset. 1733 // This is a small price to pay. 1734 1735 if (is_mcall) { 1736 last_call_offset = current_offset; 1737 } 1738 1739 if (n->is_Mach() && n->as_Mach()->avoid_back_to_back(MachNode::AVOID_AFTER)) { 1740 // Avoid back to back some instructions. 1741 last_avoid_back_to_back_offset = current_offset; 1742 } 1743 1744 // See if this instruction has a delay slot 1745 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) { 1746 guarantee(delay_slot != nullptr, "expecting delay slot node"); 1747 1748 // Back up 1 instruction 1749 cb->set_insts_end(cb->insts_end() - Pipeline::instr_unit_size()); 1750 1751 // Save the offset for the listing 1752 #if defined(SUPPORT_OPTO_ASSEMBLY) 1753 if ((node_offsets != nullptr) && (delay_slot->_idx < node_offset_limit)) { 1754 node_offsets[delay_slot->_idx] = cb->insts_size(); 1755 } 1756 #endif 1757 1758 // Support a SafePoint in the delay slot 1759 if (delay_slot->is_MachSafePoint()) { 1760 MachNode *mach = delay_slot->as_Mach(); 1761 // !!!!! Stubs only need an oopmap right now, so bail out 1762 if (!mach->is_MachCall() && mach->as_MachSafePoint()->jvms()->method() == nullptr) { 1763 // Write the oopmap directly to the code blob??!! 1764 delay_slot = nullptr; 1765 continue; 1766 } 1767 1768 int adjusted_offset = current_offset - Pipeline::instr_unit_size(); 1769 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(), 1770 adjusted_offset); 1771 // Generate an OopMap entry 1772 Process_OopMap_Node(mach, adjusted_offset); 1773 } 1774 1775 // Insert the delay slot instruction 1776 delay_slot->emit(*cb, C->regalloc()); 1777 1778 // Don't reuse it 1779 delay_slot = nullptr; 1780 } 1781 1782 } // End for all instructions in block 1783 1784 // If the next block is the top of a loop, pad this block out to align 1785 // the loop top a little. Helps prevent pipe stalls at loop back branches. 1786 if (i < nblocks-1) { 1787 Block *nb = C->cfg()->get_block(i + 1); 1788 int padding = nb->alignment_padding(current_offset); 1789 if( padding > 0 ) { 1790 MachNode *nop = new MachNopNode(padding / nop_size); 1791 block->insert_node(nop, block->number_of_nodes()); 1792 C->cfg()->map_node_to_block(nop, block); 1793 nop->emit(*cb, C->regalloc()); 1794 current_offset = cb->insts_size(); 1795 } 1796 } 1797 // Verify that the distance for generated before forward 1798 // short branches is still valid. 1799 guarantee((int)(blk_starts[i+1] - blk_starts[i]) >= (current_offset - blk_offset), "shouldn't increase block size"); 1800 1801 // Save new block start offset 1802 blk_starts[i] = blk_offset; 1803 } // End of for all blocks 1804 blk_starts[nblocks] = current_offset; 1805 1806 non_safepoints.flush_at_end(); 1807 1808 // Offset too large? 1809 if (C->failing()) return; 1810 1811 // Define a pseudo-label at the end of the code 1812 MacroAssembler(cb).bind( blk_labels[nblocks] ); 1813 1814 // Compute the size of the first block 1815 _first_block_size = blk_labels[1].loc_pos() - blk_labels[0].loc_pos(); 1816 1817 #ifdef ASSERT 1818 for (uint i = 0; i < nblocks; i++) { // For all blocks 1819 if (jmp_target[i] != 0) { 1820 int br_size = jmp_size[i]; 1821 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_offset[i]); 1822 if (!C->matcher()->is_short_branch_offset(jmp_rule[i], br_size, offset)) { 1823 tty->print_cr("target (%d) - jmp_offset(%d) = offset (%d), jump_size(%d), jmp_block B%d, target_block B%d", blk_starts[jmp_target[i]], blk_starts[i] + jmp_offset[i], offset, br_size, i, jmp_target[i]); 1824 assert(false, "Displacement too large for short jmp"); 1825 } 1826 } 1827 } 1828 #endif 1829 1830 if (!cb->finalize_stubs()) { 1831 C->record_failure("CodeCache is full"); 1832 return; 1833 } 1834 1835 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 1836 bs->emit_stubs(*cb); 1837 if (C->failing()) return; 1838 1839 // Fill in stubs. 1840 _stub_list.emit(*cb); 1841 if (C->failing()) return; 1842 1843 #ifndef PRODUCT 1844 // Information on the size of the method, without the extraneous code 1845 Scheduling::increment_method_size(cb->insts_size()); 1846 #endif 1847 1848 // ------------------ 1849 // Fill in exception table entries. 1850 FillExceptionTables(inct_cnt, call_returns, inct_starts, blk_labels); 1851 1852 // Only java methods have exception handlers and deopt handlers 1853 // class HandlerImpl is platform-specific and defined in the *.ad files. 1854 if (C->method()) { 1855 // Emit the exception handler code. 1856 _code_offsets.set_value(CodeOffsets::Exceptions, HandlerImpl::emit_exception_handler(*cb)); 1857 if (C->failing()) { 1858 return; // CodeBuffer::expand failed 1859 } 1860 // Emit the deopt handler code. 1861 _code_offsets.set_value(CodeOffsets::Deopt, HandlerImpl::emit_deopt_handler(*cb)); 1862 1863 // Emit the MethodHandle deopt handler code (if required). 1864 if (C->has_method_handle_invokes() && !C->failing()) { 1865 // We can use the same code as for the normal deopt handler, we 1866 // just need a different entry point address. 1867 _code_offsets.set_value(CodeOffsets::DeoptMH, HandlerImpl::emit_deopt_handler(*cb)); 1868 } 1869 } 1870 1871 // One last check for failed CodeBuffer::expand: 1872 if ((cb->blob() == nullptr) || (!CompileBroker::should_compile_new_jobs())) { 1873 C->record_failure("CodeCache is full"); 1874 return; 1875 } 1876 1877 #if defined(SUPPORT_ABSTRACT_ASSEMBLY) || defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_OPTO_ASSEMBLY) 1878 if (C->print_assembly()) { 1879 tty->cr(); 1880 tty->print_cr("============================= C2-compiled nmethod =============================="); 1881 } 1882 #endif 1883 1884 #if defined(SUPPORT_OPTO_ASSEMBLY) 1885 // Dump the assembly code, including basic-block numbers 1886 if (C->print_assembly()) { 1887 ttyLocker ttyl; // keep the following output all in one block 1888 if (!VMThread::should_terminate()) { // test this under the tty lock 1889 // print_metadata and dump_asm may safepoint which makes us loose the ttylock. 1890 // We call them first and write to a stringStream, then we retake the lock to 1891 // make sure the end tag is coherent, and that xmlStream->pop_tag is done thread safe. 1892 ResourceMark rm; 1893 stringStream method_metadata_str; 1894 if (C->method() != nullptr) { 1895 C->method()->print_metadata(&method_metadata_str); 1896 } 1897 stringStream dump_asm_str; 1898 dump_asm_on(&dump_asm_str, node_offsets, node_offset_limit); 1899 1900 NoSafepointVerifier nsv; 1901 ttyLocker ttyl2; 1902 // This output goes directly to the tty, not the compiler log. 1903 // To enable tools to match it up with the compilation activity, 1904 // be sure to tag this tty output with the compile ID. 1905 if (xtty != nullptr) { 1906 xtty->head("opto_assembly compile_id='%d'%s", C->compile_id(), 1907 C->is_osr_compilation() ? " compile_kind='osr'" : ""); 1908 } 1909 if (C->method() != nullptr) { 1910 tty->print_cr("----------------------- MetaData before Compile_id = %d ------------------------", C->compile_id()); 1911 tty->print_raw(method_metadata_str.freeze()); 1912 } else if (C->stub_name() != nullptr) { 1913 tty->print_cr("----------------------------- RuntimeStub %s -------------------------------", C->stub_name()); 1914 } 1915 tty->cr(); 1916 tty->print_cr("------------------------ OptoAssembly for Compile_id = %d -----------------------", C->compile_id()); 1917 tty->print_raw(dump_asm_str.freeze()); 1918 tty->print_cr("--------------------------------------------------------------------------------"); 1919 if (xtty != nullptr) { 1920 xtty->tail("opto_assembly"); 1921 } 1922 } 1923 } 1924 #endif 1925 } 1926 1927 void PhaseOutput::FillExceptionTables(uint cnt, uint *call_returns, uint *inct_starts, Label *blk_labels) { 1928 _inc_table.set_size(cnt); 1929 1930 uint inct_cnt = 0; 1931 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) { 1932 Block* block = C->cfg()->get_block(i); 1933 Node *n = nullptr; 1934 int j; 1935 1936 // Find the branch; ignore trailing NOPs. 1937 for (j = block->number_of_nodes() - 1; j >= 0; j--) { 1938 n = block->get_node(j); 1939 if (!n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con) { 1940 break; 1941 } 1942 } 1943 1944 // If we didn't find anything, continue 1945 if (j < 0) { 1946 continue; 1947 } 1948 1949 // Compute ExceptionHandlerTable subtable entry and add it 1950 // (skip empty blocks) 1951 if (n->is_Catch()) { 1952 1953 // Get the offset of the return from the call 1954 uint call_return = call_returns[block->_pre_order]; 1955 #ifdef ASSERT 1956 assert( call_return > 0, "no call seen for this basic block" ); 1957 while (block->get_node(--j)->is_MachProj()) ; 1958 assert(block->get_node(j)->is_MachCall(), "CatchProj must follow call"); 1959 #endif 1960 // last instruction is a CatchNode, find it's CatchProjNodes 1961 int nof_succs = block->_num_succs; 1962 // allocate space 1963 GrowableArray<intptr_t> handler_bcis(nof_succs); 1964 GrowableArray<intptr_t> handler_pcos(nof_succs); 1965 // iterate through all successors 1966 for (int j = 0; j < nof_succs; j++) { 1967 Block* s = block->_succs[j]; 1968 bool found_p = false; 1969 for (uint k = 1; k < s->num_preds(); k++) { 1970 Node* pk = s->pred(k); 1971 if (pk->is_CatchProj() && pk->in(0) == n) { 1972 const CatchProjNode* p = pk->as_CatchProj(); 1973 found_p = true; 1974 // add the corresponding handler bci & pco information 1975 if (p->_con != CatchProjNode::fall_through_index) { 1976 // p leads to an exception handler (and is not fall through) 1977 assert(s == C->cfg()->get_block(s->_pre_order), "bad numbering"); 1978 // no duplicates, please 1979 if (!handler_bcis.contains(p->handler_bci())) { 1980 uint block_num = s->non_connector()->_pre_order; 1981 handler_bcis.append(p->handler_bci()); 1982 handler_pcos.append(blk_labels[block_num].loc_pos()); 1983 } 1984 } 1985 } 1986 } 1987 assert(found_p, "no matching predecessor found"); 1988 // Note: Due to empty block removal, one block may have 1989 // several CatchProj inputs, from the same Catch. 1990 } 1991 1992 // Set the offset of the return from the call 1993 assert(handler_bcis.find(-1) != -1, "must have default handler"); 1994 _handler_table.add_subtable(call_return, &handler_bcis, nullptr, &handler_pcos); 1995 continue; 1996 } 1997 1998 // Handle implicit null exception table updates 1999 if (n->is_MachNullCheck()) { 2000 uint block_num = block->non_connector_successor(0)->_pre_order; 2001 _inc_table.append(inct_starts[inct_cnt++], blk_labels[block_num].loc_pos()); 2002 continue; 2003 } 2004 // Handle implicit exception table updates: trap instructions. 2005 if (n->is_Mach() && n->as_Mach()->is_TrapBasedCheckNode()) { 2006 uint block_num = block->non_connector_successor(0)->_pre_order; 2007 _inc_table.append(inct_starts[inct_cnt++], blk_labels[block_num].loc_pos()); 2008 continue; 2009 } 2010 } // End of for all blocks fill in exception table entries 2011 } 2012 2013 // Static Variables 2014 #ifndef PRODUCT 2015 uint Scheduling::_total_nop_size = 0; 2016 uint Scheduling::_total_method_size = 0; 2017 uint Scheduling::_total_branches = 0; 2018 uint Scheduling::_total_unconditional_delays = 0; 2019 uint Scheduling::_total_instructions_per_bundle[Pipeline::_max_instrs_per_cycle+1]; 2020 #endif 2021 2022 // Initializer for class Scheduling 2023 2024 Scheduling::Scheduling(Arena *arena, Compile &compile) 2025 : _arena(arena), 2026 _cfg(compile.cfg()), 2027 _regalloc(compile.regalloc()), 2028 _scheduled(arena), 2029 _available(arena), 2030 _reg_node(arena), 2031 _pinch_free_list(arena), 2032 _next_node(nullptr), 2033 _bundle_instr_count(0), 2034 _bundle_cycle_number(0), 2035 _bundle_use(0, 0, resource_count, &_bundle_use_elements[0]) 2036 #ifndef PRODUCT 2037 , _branches(0) 2038 , _unconditional_delays(0) 2039 #endif 2040 { 2041 // Create a MachNopNode 2042 _nop = new MachNopNode(); 2043 2044 // Now that the nops are in the array, save the count 2045 // (but allow entries for the nops) 2046 _node_bundling_limit = compile.unique(); 2047 uint node_max = _regalloc->node_regs_max_index(); 2048 2049 compile.output()->set_node_bundling_limit(_node_bundling_limit); 2050 2051 // This one is persistent within the Compile class 2052 _node_bundling_base = NEW_ARENA_ARRAY(compile.comp_arena(), Bundle, node_max); 2053 2054 // Allocate space for fixed-size arrays 2055 _uses = NEW_ARENA_ARRAY(arena, short, node_max); 2056 _current_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max); 2057 2058 // Clear the arrays 2059 for (uint i = 0; i < node_max; i++) { 2060 ::new (&_node_bundling_base[i]) Bundle(); 2061 } 2062 memset(_uses, 0, node_max * sizeof(short)); 2063 memset(_current_latency, 0, node_max * sizeof(unsigned short)); 2064 2065 // Clear the bundling information 2066 memcpy(_bundle_use_elements, Pipeline_Use::elaborated_elements, sizeof(Pipeline_Use::elaborated_elements)); 2067 2068 // Get the last node 2069 Block* block = _cfg->get_block(_cfg->number_of_blocks() - 1); 2070 2071 _next_node = block->get_node(block->number_of_nodes() - 1); 2072 } 2073 2074 #ifndef PRODUCT 2075 // Scheduling destructor 2076 Scheduling::~Scheduling() { 2077 _total_branches += _branches; 2078 _total_unconditional_delays += _unconditional_delays; 2079 } 2080 #endif 2081 2082 // Step ahead "i" cycles 2083 void Scheduling::step(uint i) { 2084 2085 Bundle *bundle = node_bundling(_next_node); 2086 bundle->set_starts_bundle(); 2087 2088 // Update the bundle record, but leave the flags information alone 2089 if (_bundle_instr_count > 0) { 2090 bundle->set_instr_count(_bundle_instr_count); 2091 bundle->set_resources_used(_bundle_use.resourcesUsed()); 2092 } 2093 2094 // Update the state information 2095 _bundle_instr_count = 0; 2096 _bundle_cycle_number += i; 2097 _bundle_use.step(i); 2098 } 2099 2100 void Scheduling::step_and_clear() { 2101 Bundle *bundle = node_bundling(_next_node); 2102 bundle->set_starts_bundle(); 2103 2104 // Update the bundle record 2105 if (_bundle_instr_count > 0) { 2106 bundle->set_instr_count(_bundle_instr_count); 2107 bundle->set_resources_used(_bundle_use.resourcesUsed()); 2108 2109 _bundle_cycle_number += 1; 2110 } 2111 2112 // Clear the bundling information 2113 _bundle_instr_count = 0; 2114 _bundle_use.reset(); 2115 2116 memcpy(_bundle_use_elements, 2117 Pipeline_Use::elaborated_elements, 2118 sizeof(Pipeline_Use::elaborated_elements)); 2119 } 2120 2121 // Perform instruction scheduling and bundling over the sequence of 2122 // instructions in backwards order. 2123 void PhaseOutput::ScheduleAndBundle() { 2124 2125 // Don't optimize this if it isn't a method 2126 if (!C->method()) 2127 return; 2128 2129 // Don't optimize this if scheduling is disabled 2130 if (!C->do_scheduling()) 2131 return; 2132 2133 // Scheduling code works only with pairs (8 bytes) maximum. 2134 // And when the scalable vector register is used, we may spill/unspill 2135 // the whole reg regardless of the max vector size. 2136 if (C->max_vector_size() > 8 || 2137 (C->max_vector_size() > 0 && Matcher::supports_scalable_vector())) { 2138 return; 2139 } 2140 2141 Compile::TracePhase tp("isched", &timers[_t_instrSched]); 2142 2143 // Create a data structure for all the scheduling information 2144 Scheduling scheduling(Thread::current()->resource_area(), *C); 2145 2146 // Walk backwards over each basic block, computing the needed alignment 2147 // Walk over all the basic blocks 2148 scheduling.DoScheduling(); 2149 2150 #ifndef PRODUCT 2151 if (C->trace_opto_output()) { 2152 // Buffer and print all at once 2153 ResourceMark rm; 2154 stringStream ss; 2155 ss.print("\n---- After ScheduleAndBundle ----\n"); 2156 print_scheduling(&ss); 2157 tty->print("%s", ss.as_string()); 2158 } 2159 #endif 2160 } 2161 2162 #ifndef PRODUCT 2163 // Separated out so that it can be called directly from debugger 2164 void PhaseOutput::print_scheduling() { 2165 print_scheduling(tty); 2166 } 2167 2168 void PhaseOutput::print_scheduling(outputStream* output_stream) { 2169 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) { 2170 output_stream->print("\nBB#%03d:\n", i); 2171 Block* block = C->cfg()->get_block(i); 2172 for (uint j = 0; j < block->number_of_nodes(); j++) { 2173 Node* n = block->get_node(j); 2174 OptoReg::Name reg = C->regalloc()->get_reg_first(n); 2175 output_stream->print(" %-6s ", reg >= 0 && reg < REG_COUNT ? Matcher::regName[reg] : ""); 2176 n->dump("\n", false, output_stream); 2177 } 2178 } 2179 } 2180 #endif 2181 2182 // See if this node fits into the present instruction bundle 2183 bool Scheduling::NodeFitsInBundle(Node *n) { 2184 uint n_idx = n->_idx; 2185 2186 // If this is the unconditional delay instruction, then it fits 2187 if (n == _unconditional_delay_slot) { 2188 #ifndef PRODUCT 2189 if (_cfg->C->trace_opto_output()) 2190 tty->print("# NodeFitsInBundle [%4d]: TRUE; is in unconditional delay slot\n", n->_idx); 2191 #endif 2192 return (true); 2193 } 2194 2195 // If the node cannot be scheduled this cycle, skip it 2196 if (_current_latency[n_idx] > _bundle_cycle_number) { 2197 #ifndef PRODUCT 2198 if (_cfg->C->trace_opto_output()) 2199 tty->print("# NodeFitsInBundle [%4d]: FALSE; latency %4d > %d\n", 2200 n->_idx, _current_latency[n_idx], _bundle_cycle_number); 2201 #endif 2202 return (false); 2203 } 2204 2205 const Pipeline *node_pipeline = n->pipeline(); 2206 2207 uint instruction_count = node_pipeline->instructionCount(); 2208 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0) 2209 instruction_count = 0; 2210 else if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot) 2211 instruction_count++; 2212 2213 if (_bundle_instr_count + instruction_count > Pipeline::_max_instrs_per_cycle) { 2214 #ifndef PRODUCT 2215 if (_cfg->C->trace_opto_output()) 2216 tty->print("# NodeFitsInBundle [%4d]: FALSE; too many instructions: %d > %d\n", 2217 n->_idx, _bundle_instr_count + instruction_count, Pipeline::_max_instrs_per_cycle); 2218 #endif 2219 return (false); 2220 } 2221 2222 // Don't allow non-machine nodes to be handled this way 2223 if (!n->is_Mach() && instruction_count == 0) 2224 return (false); 2225 2226 // See if there is any overlap 2227 uint delay = _bundle_use.full_latency(0, node_pipeline->resourceUse()); 2228 2229 if (delay > 0) { 2230 #ifndef PRODUCT 2231 if (_cfg->C->trace_opto_output()) 2232 tty->print("# NodeFitsInBundle [%4d]: FALSE; functional units overlap\n", n_idx); 2233 #endif 2234 return false; 2235 } 2236 2237 #ifndef PRODUCT 2238 if (_cfg->C->trace_opto_output()) 2239 tty->print("# NodeFitsInBundle [%4d]: TRUE\n", n_idx); 2240 #endif 2241 2242 return true; 2243 } 2244 2245 Node * Scheduling::ChooseNodeToBundle() { 2246 uint siz = _available.size(); 2247 2248 if (siz == 0) { 2249 2250 #ifndef PRODUCT 2251 if (_cfg->C->trace_opto_output()) 2252 tty->print("# ChooseNodeToBundle: null\n"); 2253 #endif 2254 return (nullptr); 2255 } 2256 2257 // Fast path, if only 1 instruction in the bundle 2258 if (siz == 1) { 2259 #ifndef PRODUCT 2260 if (_cfg->C->trace_opto_output()) { 2261 tty->print("# ChooseNodeToBundle (only 1): "); 2262 _available[0]->dump(); 2263 } 2264 #endif 2265 return (_available[0]); 2266 } 2267 2268 // Don't bother, if the bundle is already full 2269 if (_bundle_instr_count < Pipeline::_max_instrs_per_cycle) { 2270 for ( uint i = 0; i < siz; i++ ) { 2271 Node *n = _available[i]; 2272 2273 // Skip projections, we'll handle them another way 2274 if (n->is_Proj()) 2275 continue; 2276 2277 // This presupposed that instructions are inserted into the 2278 // available list in a legality order; i.e. instructions that 2279 // must be inserted first are at the head of the list 2280 if (NodeFitsInBundle(n)) { 2281 #ifndef PRODUCT 2282 if (_cfg->C->trace_opto_output()) { 2283 tty->print("# ChooseNodeToBundle: "); 2284 n->dump(); 2285 } 2286 #endif 2287 return (n); 2288 } 2289 } 2290 } 2291 2292 // Nothing fits in this bundle, choose the highest priority 2293 #ifndef PRODUCT 2294 if (_cfg->C->trace_opto_output()) { 2295 tty->print("# ChooseNodeToBundle: "); 2296 _available[0]->dump(); 2297 } 2298 #endif 2299 2300 return _available[0]; 2301 } 2302 2303 int Scheduling::compare_two_spill_nodes(Node* first, Node* second) { 2304 assert(first->is_MachSpillCopy() && second->is_MachSpillCopy(), ""); 2305 2306 OptoReg::Name first_src_lo = _regalloc->get_reg_first(first->in(1)); 2307 OptoReg::Name first_dst_lo = _regalloc->get_reg_first(first); 2308 OptoReg::Name second_src_lo = _regalloc->get_reg_first(second->in(1)); 2309 OptoReg::Name second_dst_lo = _regalloc->get_reg_first(second); 2310 2311 // Comparison between stack -> reg and stack -> reg 2312 if (OptoReg::is_stack(first_src_lo) && OptoReg::is_stack(second_src_lo) && 2313 OptoReg::is_reg(first_dst_lo) && OptoReg::is_reg(second_dst_lo)) { 2314 return _regalloc->reg2offset(first_src_lo) - _regalloc->reg2offset(second_src_lo); 2315 } 2316 2317 // Comparison between reg -> stack and reg -> stack 2318 if (OptoReg::is_stack(first_dst_lo) && OptoReg::is_stack(second_dst_lo) && 2319 OptoReg::is_reg(first_src_lo) && OptoReg::is_reg(second_src_lo)) { 2320 return _regalloc->reg2offset(first_dst_lo) - _regalloc->reg2offset(second_dst_lo); 2321 } 2322 2323 return 0; // Not comparable 2324 } 2325 2326 void Scheduling::AddNodeToAvailableList(Node *n) { 2327 assert( !n->is_Proj(), "projections never directly made available" ); 2328 #ifndef PRODUCT 2329 if (_cfg->C->trace_opto_output()) { 2330 tty->print("# AddNodeToAvailableList: "); 2331 n->dump(); 2332 } 2333 #endif 2334 2335 int latency = _current_latency[n->_idx]; 2336 2337 // Insert in latency order (insertion sort). If two MachSpillCopyNodes 2338 // for stack spilling or unspilling have the same latency, we sort 2339 // them in the order of stack offset. Some ports (e.g. aarch64) may also 2340 // have more opportunities to do ld/st merging 2341 uint i; 2342 for (i = 0; i < _available.size(); i++) { 2343 if (_current_latency[_available[i]->_idx] > latency) { 2344 break; 2345 } else if (_current_latency[_available[i]->_idx] == latency && 2346 n->is_MachSpillCopy() && _available[i]->is_MachSpillCopy() && 2347 compare_two_spill_nodes(n, _available[i]) > 0) { 2348 break; 2349 } 2350 } 2351 2352 // Special Check for compares following branches 2353 if( n->is_Mach() && _scheduled.size() > 0 ) { 2354 int op = n->as_Mach()->ideal_Opcode(); 2355 Node *last = _scheduled[0]; 2356 if( last->is_MachIf() && last->in(1) == n && 2357 ( op == Op_CmpI || 2358 op == Op_CmpU || 2359 op == Op_CmpUL || 2360 op == Op_CmpP || 2361 op == Op_CmpF || 2362 op == Op_CmpD || 2363 op == Op_CmpL ) ) { 2364 2365 // Recalculate position, moving to front of same latency 2366 for ( i=0 ; i < _available.size(); i++ ) 2367 if (_current_latency[_available[i]->_idx] >= latency) 2368 break; 2369 } 2370 } 2371 2372 // Insert the node in the available list 2373 _available.insert(i, n); 2374 2375 #ifndef PRODUCT 2376 if (_cfg->C->trace_opto_output()) 2377 dump_available(); 2378 #endif 2379 } 2380 2381 void Scheduling::DecrementUseCounts(Node *n, const Block *bb) { 2382 for ( uint i=0; i < n->len(); i++ ) { 2383 Node *def = n->in(i); 2384 if (!def) continue; 2385 if( def->is_Proj() ) // If this is a machine projection, then 2386 def = def->in(0); // propagate usage thru to the base instruction 2387 2388 if(_cfg->get_block_for_node(def) != bb) { // Ignore if not block-local 2389 continue; 2390 } 2391 2392 // Compute the latency 2393 uint l = _bundle_cycle_number + n->latency(i); 2394 if (_current_latency[def->_idx] < l) 2395 _current_latency[def->_idx] = l; 2396 2397 // If this does not have uses then schedule it 2398 if ((--_uses[def->_idx]) == 0) 2399 AddNodeToAvailableList(def); 2400 } 2401 } 2402 2403 void Scheduling::AddNodeToBundle(Node *n, const Block *bb) { 2404 #ifndef PRODUCT 2405 if (_cfg->C->trace_opto_output()) { 2406 tty->print("# AddNodeToBundle: "); 2407 n->dump(); 2408 } 2409 #endif 2410 2411 // Remove this from the available list 2412 uint i; 2413 for (i = 0; i < _available.size(); i++) 2414 if (_available[i] == n) 2415 break; 2416 assert(i < _available.size(), "entry in _available list not found"); 2417 _available.remove(i); 2418 2419 // See if this fits in the current bundle 2420 const Pipeline *node_pipeline = n->pipeline(); 2421 const Pipeline_Use& node_usage = node_pipeline->resourceUse(); 2422 2423 // Check for instructions to be placed in the delay slot. We 2424 // do this before we actually schedule the current instruction, 2425 // because the delay slot follows the current instruction. 2426 if (Pipeline::_branch_has_delay_slot && 2427 node_pipeline->hasBranchDelay() && 2428 !_unconditional_delay_slot) { 2429 2430 uint siz = _available.size(); 2431 2432 // Conditional branches can support an instruction that 2433 // is unconditionally executed and not dependent by the 2434 // branch, OR a conditionally executed instruction if 2435 // the branch is taken. In practice, this means that 2436 // the first instruction at the branch target is 2437 // copied to the delay slot, and the branch goes to 2438 // the instruction after that at the branch target 2439 if ( n->is_MachBranch() ) { 2440 2441 assert( !n->is_MachNullCheck(), "should not look for delay slot for Null Check" ); 2442 assert( !n->is_Catch(), "should not look for delay slot for Catch" ); 2443 2444 #ifndef PRODUCT 2445 _branches++; 2446 #endif 2447 2448 // At least 1 instruction is on the available list 2449 // that is not dependent on the branch 2450 for (uint i = 0; i < siz; i++) { 2451 Node *d = _available[i]; 2452 const Pipeline *avail_pipeline = d->pipeline(); 2453 2454 // Don't allow safepoints in the branch shadow, that will 2455 // cause a number of difficulties 2456 if ( avail_pipeline->instructionCount() == 1 && 2457 !avail_pipeline->hasMultipleBundles() && 2458 !avail_pipeline->hasBranchDelay() && 2459 Pipeline::instr_has_unit_size() && 2460 d->size(_regalloc) == Pipeline::instr_unit_size() && 2461 NodeFitsInBundle(d) && 2462 !node_bundling(d)->used_in_delay()) { 2463 2464 if (d->is_Mach() && !d->is_MachSafePoint()) { 2465 // A node that fits in the delay slot was found, so we need to 2466 // set the appropriate bits in the bundle pipeline information so 2467 // that it correctly indicates resource usage. Later, when we 2468 // attempt to add this instruction to the bundle, we will skip 2469 // setting the resource usage. 2470 _unconditional_delay_slot = d; 2471 node_bundling(n)->set_use_unconditional_delay(); 2472 node_bundling(d)->set_used_in_unconditional_delay(); 2473 _bundle_use.add_usage(avail_pipeline->resourceUse()); 2474 _current_latency[d->_idx] = _bundle_cycle_number; 2475 _next_node = d; 2476 ++_bundle_instr_count; 2477 #ifndef PRODUCT 2478 _unconditional_delays++; 2479 #endif 2480 break; 2481 } 2482 } 2483 } 2484 } 2485 2486 // No delay slot, add a nop to the usage 2487 if (!_unconditional_delay_slot) { 2488 // See if adding an instruction in the delay slot will overflow 2489 // the bundle. 2490 if (!NodeFitsInBundle(_nop)) { 2491 #ifndef PRODUCT 2492 if (_cfg->C->trace_opto_output()) 2493 tty->print("# *** STEP(1 instruction for delay slot) ***\n"); 2494 #endif 2495 step(1); 2496 } 2497 2498 _bundle_use.add_usage(_nop->pipeline()->resourceUse()); 2499 _next_node = _nop; 2500 ++_bundle_instr_count; 2501 } 2502 2503 // See if the instruction in the delay slot requires a 2504 // step of the bundles 2505 if (!NodeFitsInBundle(n)) { 2506 #ifndef PRODUCT 2507 if (_cfg->C->trace_opto_output()) 2508 tty->print("# *** STEP(branch won't fit) ***\n"); 2509 #endif 2510 // Update the state information 2511 _bundle_instr_count = 0; 2512 _bundle_cycle_number += 1; 2513 _bundle_use.step(1); 2514 } 2515 } 2516 2517 // Get the number of instructions 2518 uint instruction_count = node_pipeline->instructionCount(); 2519 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0) 2520 instruction_count = 0; 2521 2522 // Compute the latency information 2523 uint delay = 0; 2524 2525 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) { 2526 int relative_latency = _current_latency[n->_idx] - _bundle_cycle_number; 2527 if (relative_latency < 0) 2528 relative_latency = 0; 2529 2530 delay = _bundle_use.full_latency(relative_latency, node_usage); 2531 2532 // Does not fit in this bundle, start a new one 2533 if (delay > 0) { 2534 step(delay); 2535 2536 #ifndef PRODUCT 2537 if (_cfg->C->trace_opto_output()) 2538 tty->print("# *** STEP(%d) ***\n", delay); 2539 #endif 2540 } 2541 } 2542 2543 // If this was placed in the delay slot, ignore it 2544 if (n != _unconditional_delay_slot) { 2545 2546 if (delay == 0) { 2547 if (node_pipeline->hasMultipleBundles()) { 2548 #ifndef PRODUCT 2549 if (_cfg->C->trace_opto_output()) 2550 tty->print("# *** STEP(multiple instructions) ***\n"); 2551 #endif 2552 step(1); 2553 } 2554 2555 else if (instruction_count + _bundle_instr_count > Pipeline::_max_instrs_per_cycle) { 2556 #ifndef PRODUCT 2557 if (_cfg->C->trace_opto_output()) 2558 tty->print("# *** STEP(%d >= %d instructions) ***\n", 2559 instruction_count + _bundle_instr_count, 2560 Pipeline::_max_instrs_per_cycle); 2561 #endif 2562 step(1); 2563 } 2564 } 2565 2566 if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot) 2567 _bundle_instr_count++; 2568 2569 // Set the node's latency 2570 _current_latency[n->_idx] = _bundle_cycle_number; 2571 2572 // Now merge the functional unit information 2573 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) 2574 _bundle_use.add_usage(node_usage); 2575 2576 // Increment the number of instructions in this bundle 2577 _bundle_instr_count += instruction_count; 2578 2579 // Remember this node for later 2580 if (n->is_Mach()) 2581 _next_node = n; 2582 } 2583 2584 // It's possible to have a BoxLock in the graph and in the _bbs mapping but 2585 // not in the bb->_nodes array. This happens for debug-info-only BoxLocks. 2586 // 'Schedule' them (basically ignore in the schedule) but do not insert them 2587 // into the block. All other scheduled nodes get put in the schedule here. 2588 int op = n->Opcode(); 2589 if( (op == Op_Node && n->req() == 0) || // anti-dependence node OR 2590 (op != Op_Node && // Not an unused antidepedence node and 2591 // not an unallocated boxlock 2592 (OptoReg::is_valid(_regalloc->get_reg_first(n)) || op != Op_BoxLock)) ) { 2593 2594 // Push any trailing projections 2595 if( bb->get_node(bb->number_of_nodes()-1) != n ) { 2596 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2597 Node *foi = n->fast_out(i); 2598 if( foi->is_Proj() ) 2599 _scheduled.push(foi); 2600 } 2601 } 2602 2603 // Put the instruction in the schedule list 2604 _scheduled.push(n); 2605 } 2606 2607 #ifndef PRODUCT 2608 if (_cfg->C->trace_opto_output()) 2609 dump_available(); 2610 #endif 2611 2612 // Walk all the definitions, decrementing use counts, and 2613 // if a definition has a 0 use count, place it in the available list. 2614 DecrementUseCounts(n,bb); 2615 } 2616 2617 // This method sets the use count within a basic block. We will ignore all 2618 // uses outside the current basic block. As we are doing a backwards walk, 2619 // any node we reach that has a use count of 0 may be scheduled. This also 2620 // avoids the problem of cyclic references from phi nodes, as long as phi 2621 // nodes are at the front of the basic block. This method also initializes 2622 // the available list to the set of instructions that have no uses within this 2623 // basic block. 2624 void Scheduling::ComputeUseCount(const Block *bb) { 2625 #ifndef PRODUCT 2626 if (_cfg->C->trace_opto_output()) 2627 tty->print("# -> ComputeUseCount\n"); 2628 #endif 2629 2630 // Clear the list of available and scheduled instructions, just in case 2631 _available.clear(); 2632 _scheduled.clear(); 2633 2634 // No delay slot specified 2635 _unconditional_delay_slot = nullptr; 2636 2637 #ifdef ASSERT 2638 for( uint i=0; i < bb->number_of_nodes(); i++ ) 2639 assert( _uses[bb->get_node(i)->_idx] == 0, "_use array not clean" ); 2640 #endif 2641 2642 // Force the _uses count to never go to zero for unscheduable pieces 2643 // of the block 2644 for( uint k = 0; k < _bb_start; k++ ) 2645 _uses[bb->get_node(k)->_idx] = 1; 2646 for( uint l = _bb_end; l < bb->number_of_nodes(); l++ ) 2647 _uses[bb->get_node(l)->_idx] = 1; 2648 2649 // Iterate backwards over the instructions in the block. Don't count the 2650 // branch projections at end or the block header instructions. 2651 for( uint j = _bb_end-1; j >= _bb_start; j-- ) { 2652 Node *n = bb->get_node(j); 2653 if( n->is_Proj() ) continue; // Projections handled another way 2654 2655 // Account for all uses 2656 for ( uint k = 0; k < n->len(); k++ ) { 2657 Node *inp = n->in(k); 2658 if (!inp) continue; 2659 assert(inp != n, "no cycles allowed" ); 2660 if (_cfg->get_block_for_node(inp) == bb) { // Block-local use? 2661 if (inp->is_Proj()) { // Skip through Proj's 2662 inp = inp->in(0); 2663 } 2664 ++_uses[inp->_idx]; // Count 1 block-local use 2665 } 2666 } 2667 2668 // If this instruction has a 0 use count, then it is available 2669 if (!_uses[n->_idx]) { 2670 _current_latency[n->_idx] = _bundle_cycle_number; 2671 AddNodeToAvailableList(n); 2672 } 2673 2674 #ifndef PRODUCT 2675 if (_cfg->C->trace_opto_output()) { 2676 tty->print("# uses: %3d: ", _uses[n->_idx]); 2677 n->dump(); 2678 } 2679 #endif 2680 } 2681 2682 #ifndef PRODUCT 2683 if (_cfg->C->trace_opto_output()) 2684 tty->print("# <- ComputeUseCount\n"); 2685 #endif 2686 } 2687 2688 // This routine performs scheduling on each basic block in reverse order, 2689 // using instruction latencies and taking into account function unit 2690 // availability. 2691 void Scheduling::DoScheduling() { 2692 #ifndef PRODUCT 2693 if (_cfg->C->trace_opto_output()) 2694 tty->print("# -> DoScheduling\n"); 2695 #endif 2696 2697 Block *succ_bb = nullptr; 2698 Block *bb; 2699 Compile* C = Compile::current(); 2700 2701 // Walk over all the basic blocks in reverse order 2702 for (int i = _cfg->number_of_blocks() - 1; i >= 0; succ_bb = bb, i--) { 2703 bb = _cfg->get_block(i); 2704 2705 #ifndef PRODUCT 2706 if (_cfg->C->trace_opto_output()) { 2707 tty->print("# Schedule BB#%03d (initial)\n", i); 2708 for (uint j = 0; j < bb->number_of_nodes(); j++) { 2709 bb->get_node(j)->dump(); 2710 } 2711 } 2712 #endif 2713 2714 // On the head node, skip processing 2715 if (bb == _cfg->get_root_block()) { 2716 continue; 2717 } 2718 2719 // Skip empty, connector blocks 2720 if (bb->is_connector()) 2721 continue; 2722 2723 // If the following block is not the sole successor of 2724 // this one, then reset the pipeline information 2725 if (bb->_num_succs != 1 || bb->non_connector_successor(0) != succ_bb) { 2726 #ifndef PRODUCT 2727 if (_cfg->C->trace_opto_output()) { 2728 tty->print("*** bundle start of next BB, node %d, for %d instructions\n", 2729 _next_node->_idx, _bundle_instr_count); 2730 } 2731 #endif 2732 step_and_clear(); 2733 } 2734 2735 // Leave untouched the starting instruction, any Phis, a CreateEx node 2736 // or Top. bb->get_node(_bb_start) is the first schedulable instruction. 2737 _bb_end = bb->number_of_nodes()-1; 2738 for( _bb_start=1; _bb_start <= _bb_end; _bb_start++ ) { 2739 Node *n = bb->get_node(_bb_start); 2740 // Things not matched, like Phinodes and ProjNodes don't get scheduled. 2741 // Also, MachIdealNodes do not get scheduled 2742 if( !n->is_Mach() ) continue; // Skip non-machine nodes 2743 MachNode *mach = n->as_Mach(); 2744 int iop = mach->ideal_Opcode(); 2745 if( iop == Op_CreateEx ) continue; // CreateEx is pinned 2746 if( iop == Op_Con ) continue; // Do not schedule Top 2747 if( iop == Op_Node && // Do not schedule PhiNodes, ProjNodes 2748 mach->pipeline() == MachNode::pipeline_class() && 2749 !n->is_SpillCopy() && !n->is_MachMerge() ) // Breakpoints, Prolog, etc 2750 continue; 2751 break; // Funny loop structure to be sure... 2752 } 2753 // Compute last "interesting" instruction in block - last instruction we 2754 // might schedule. _bb_end points just after last schedulable inst. We 2755 // normally schedule conditional branches (despite them being forced last 2756 // in the block), because they have delay slots we can fill. Calls all 2757 // have their delay slots filled in the template expansions, so we don't 2758 // bother scheduling them. 2759 Node *last = bb->get_node(_bb_end); 2760 // Ignore trailing NOPs. 2761 while (_bb_end > 0 && last->is_Mach() && 2762 last->as_Mach()->ideal_Opcode() == Op_Con) { 2763 last = bb->get_node(--_bb_end); 2764 } 2765 assert(!last->is_Mach() || last->as_Mach()->ideal_Opcode() != Op_Con, ""); 2766 if( last->is_Catch() || 2767 (last->is_Mach() && last->as_Mach()->ideal_Opcode() == Op_Halt) ) { 2768 // There might be a prior call. Skip it. 2769 while (_bb_start < _bb_end && bb->get_node(--_bb_end)->is_MachProj()); 2770 } else if( last->is_MachNullCheck() ) { 2771 // Backup so the last null-checked memory instruction is 2772 // outside the schedulable range. Skip over the nullcheck, 2773 // projection, and the memory nodes. 2774 Node *mem = last->in(1); 2775 do { 2776 _bb_end--; 2777 } while (mem != bb->get_node(_bb_end)); 2778 } else { 2779 // Set _bb_end to point after last schedulable inst. 2780 _bb_end++; 2781 } 2782 2783 assert( _bb_start <= _bb_end, "inverted block ends" ); 2784 2785 // Compute the register antidependencies for the basic block 2786 ComputeRegisterAntidependencies(bb); 2787 if (C->failing()) return; // too many D-U pinch points 2788 2789 // Compute the usage within the block, and set the list of all nodes 2790 // in the block that have no uses within the block. 2791 ComputeUseCount(bb); 2792 2793 // Schedule the remaining instructions in the block 2794 while ( _available.size() > 0 ) { 2795 Node *n = ChooseNodeToBundle(); 2796 guarantee(n != nullptr, "no nodes available"); 2797 AddNodeToBundle(n,bb); 2798 } 2799 2800 assert( _scheduled.size() == _bb_end - _bb_start, "wrong number of instructions" ); 2801 #ifdef ASSERT 2802 for( uint l = _bb_start; l < _bb_end; l++ ) { 2803 Node *n = bb->get_node(l); 2804 uint m; 2805 for( m = 0; m < _bb_end-_bb_start; m++ ) 2806 if( _scheduled[m] == n ) 2807 break; 2808 assert( m < _bb_end-_bb_start, "instruction missing in schedule" ); 2809 } 2810 #endif 2811 2812 // Now copy the instructions (in reverse order) back to the block 2813 for ( uint k = _bb_start; k < _bb_end; k++ ) 2814 bb->map_node(_scheduled[_bb_end-k-1], k); 2815 2816 #ifndef PRODUCT 2817 if (_cfg->C->trace_opto_output()) { 2818 tty->print("# Schedule BB#%03d (final)\n", i); 2819 uint current = 0; 2820 for (uint j = 0; j < bb->number_of_nodes(); j++) { 2821 Node *n = bb->get_node(j); 2822 if( valid_bundle_info(n) ) { 2823 Bundle *bundle = node_bundling(n); 2824 if (bundle->instr_count() > 0 || bundle->flags() > 0) { 2825 tty->print("*** Bundle: "); 2826 bundle->dump(); 2827 } 2828 n->dump(); 2829 } 2830 } 2831 } 2832 #endif 2833 #ifdef ASSERT 2834 verify_good_schedule(bb,"after block local scheduling"); 2835 #endif 2836 } 2837 2838 #ifndef PRODUCT 2839 if (_cfg->C->trace_opto_output()) 2840 tty->print("# <- DoScheduling\n"); 2841 #endif 2842 2843 // Record final node-bundling array location 2844 _regalloc->C->output()->set_node_bundling_base(_node_bundling_base); 2845 2846 } // end DoScheduling 2847 2848 // Verify that no live-range used in the block is killed in the block by a 2849 // wrong DEF. This doesn't verify live-ranges that span blocks. 2850 2851 // Check for edge existence. Used to avoid adding redundant precedence edges. 2852 static bool edge_from_to( Node *from, Node *to ) { 2853 for( uint i=0; i<from->len(); i++ ) 2854 if( from->in(i) == to ) 2855 return true; 2856 return false; 2857 } 2858 2859 #ifdef ASSERT 2860 void Scheduling::verify_do_def( Node *n, OptoReg::Name def, const char *msg ) { 2861 // Check for bad kills 2862 if( OptoReg::is_valid(def) ) { // Ignore stores & control flow 2863 Node *prior_use = _reg_node[def]; 2864 if( prior_use && !edge_from_to(prior_use,n) ) { 2865 tty->print("%s = ",OptoReg::as_VMReg(def)->name()); 2866 n->dump(); 2867 tty->print_cr("..."); 2868 prior_use->dump(); 2869 assert(edge_from_to(prior_use,n), "%s", msg); 2870 } 2871 _reg_node.map(def,nullptr); // Kill live USEs 2872 } 2873 } 2874 2875 void Scheduling::verify_good_schedule( Block *b, const char *msg ) { 2876 2877 // Zap to something reasonable for the verify code 2878 _reg_node.clear(); 2879 2880 // Walk over the block backwards. Check to make sure each DEF doesn't 2881 // kill a live value (other than the one it's supposed to). Add each 2882 // USE to the live set. 2883 for( uint i = b->number_of_nodes()-1; i >= _bb_start; i-- ) { 2884 Node *n = b->get_node(i); 2885 int n_op = n->Opcode(); 2886 if( n_op == Op_MachProj && n->ideal_reg() == MachProjNode::fat_proj ) { 2887 // Fat-proj kills a slew of registers 2888 RegMaskIterator rmi(n->out_RegMask()); 2889 while (rmi.has_next()) { 2890 OptoReg::Name kill = rmi.next(); 2891 verify_do_def(n, kill, msg); 2892 } 2893 } else if( n_op != Op_Node ) { // Avoid brand new antidependence nodes 2894 // Get DEF'd registers the normal way 2895 verify_do_def( n, _regalloc->get_reg_first(n), msg ); 2896 verify_do_def( n, _regalloc->get_reg_second(n), msg ); 2897 } 2898 2899 // Now make all USEs live 2900 for( uint i=1; i<n->req(); i++ ) { 2901 Node *def = n->in(i); 2902 assert(def != 0, "input edge required"); 2903 OptoReg::Name reg_lo = _regalloc->get_reg_first(def); 2904 OptoReg::Name reg_hi = _regalloc->get_reg_second(def); 2905 if( OptoReg::is_valid(reg_lo) ) { 2906 assert(!_reg_node[reg_lo] || edge_from_to(_reg_node[reg_lo],def), "%s", msg); 2907 _reg_node.map(reg_lo,n); 2908 } 2909 if( OptoReg::is_valid(reg_hi) ) { 2910 assert(!_reg_node[reg_hi] || edge_from_to(_reg_node[reg_hi],def), "%s", msg); 2911 _reg_node.map(reg_hi,n); 2912 } 2913 } 2914 2915 } 2916 2917 // Zap to something reasonable for the Antidependence code 2918 _reg_node.clear(); 2919 } 2920 #endif 2921 2922 // Conditionally add precedence edges. Avoid putting edges on Projs. 2923 static void add_prec_edge_from_to( Node *from, Node *to ) { 2924 if( from->is_Proj() ) { // Put precedence edge on Proj's input 2925 assert( from->req() == 1 && (from->len() == 1 || from->in(1)==0), "no precedence edges on projections" ); 2926 from = from->in(0); 2927 } 2928 if( from != to && // No cycles (for things like LD L0,[L0+4] ) 2929 !edge_from_to( from, to ) ) // Avoid duplicate edge 2930 from->add_prec(to); 2931 } 2932 2933 void Scheduling::anti_do_def( Block *b, Node *def, OptoReg::Name def_reg, int is_def ) { 2934 if( !OptoReg::is_valid(def_reg) ) // Ignore stores & control flow 2935 return; 2936 2937 if (OptoReg::is_reg(def_reg)) { 2938 VMReg vmreg = OptoReg::as_VMReg(def_reg); 2939 if (vmreg->is_reg() && !vmreg->is_concrete() && !vmreg->prev()->is_concrete()) { 2940 // This is one of the high slots of a vector register. 2941 // ScheduleAndBundle already checked there are no live wide 2942 // vectors in this method so it can be safely ignored. 2943 return; 2944 } 2945 } 2946 2947 Node *pinch = _reg_node[def_reg]; // Get pinch point 2948 if ((pinch == nullptr) || _cfg->get_block_for_node(pinch) != b || // No pinch-point yet? 2949 is_def ) { // Check for a true def (not a kill) 2950 _reg_node.map(def_reg,def); // Record def/kill as the optimistic pinch-point 2951 return; 2952 } 2953 2954 Node *kill = def; // Rename 'def' to more descriptive 'kill' 2955 debug_only( def = (Node*)((intptr_t)0xdeadbeef); ) 2956 2957 // After some number of kills there _may_ be a later def 2958 Node *later_def = nullptr; 2959 2960 Compile* C = Compile::current(); 2961 2962 // Finding a kill requires a real pinch-point. 2963 // Check for not already having a pinch-point. 2964 // Pinch points are Op_Node's. 2965 if( pinch->Opcode() != Op_Node ) { // Or later-def/kill as pinch-point? 2966 later_def = pinch; // Must be def/kill as optimistic pinch-point 2967 if ( _pinch_free_list.size() > 0) { 2968 pinch = _pinch_free_list.pop(); 2969 } else { 2970 pinch = new Node(1); // Pinch point to-be 2971 } 2972 if (pinch->_idx >= _regalloc->node_regs_max_index()) { 2973 DEBUG_ONLY( pinch->dump(); ); 2974 assert(false, "too many D-U pinch points: %d >= %d", pinch->_idx, _regalloc->node_regs_max_index()); 2975 _cfg->C->record_method_not_compilable("too many D-U pinch points"); 2976 return; 2977 } 2978 _cfg->map_node_to_block(pinch, b); // Pretend it's valid in this block (lazy init) 2979 _reg_node.map(def_reg,pinch); // Record pinch-point 2980 //regalloc()->set_bad(pinch->_idx); // Already initialized this way. 2981 if( later_def->outcnt() == 0 || later_def->ideal_reg() == MachProjNode::fat_proj ) { // Distinguish def from kill 2982 pinch->init_req(0, C->top()); // set not null for the next call 2983 add_prec_edge_from_to(later_def,pinch); // Add edge from kill to pinch 2984 later_def = nullptr; // and no later def 2985 } 2986 pinch->set_req(0,later_def); // Hook later def so we can find it 2987 } else { // Else have valid pinch point 2988 if( pinch->in(0) ) // If there is a later-def 2989 later_def = pinch->in(0); // Get it 2990 } 2991 2992 // Add output-dependence edge from later def to kill 2993 if( later_def ) // If there is some original def 2994 add_prec_edge_from_to(later_def,kill); // Add edge from def to kill 2995 2996 // See if current kill is also a use, and so is forced to be the pinch-point. 2997 if( pinch->Opcode() == Op_Node ) { 2998 Node *uses = kill->is_Proj() ? kill->in(0) : kill; 2999 for( uint i=1; i<uses->req(); i++ ) { 3000 if( _regalloc->get_reg_first(uses->in(i)) == def_reg || 3001 _regalloc->get_reg_second(uses->in(i)) == def_reg ) { 3002 // Yes, found a use/kill pinch-point 3003 pinch->set_req(0,nullptr); // 3004 pinch->replace_by(kill); // Move anti-dep edges up 3005 pinch = kill; 3006 _reg_node.map(def_reg,pinch); 3007 return; 3008 } 3009 } 3010 } 3011 3012 // Add edge from kill to pinch-point 3013 add_prec_edge_from_to(kill,pinch); 3014 } 3015 3016 void Scheduling::anti_do_use( Block *b, Node *use, OptoReg::Name use_reg ) { 3017 if( !OptoReg::is_valid(use_reg) ) // Ignore stores & control flow 3018 return; 3019 Node *pinch = _reg_node[use_reg]; // Get pinch point 3020 // Check for no later def_reg/kill in block 3021 if ((pinch != nullptr) && _cfg->get_block_for_node(pinch) == b && 3022 // Use has to be block-local as well 3023 _cfg->get_block_for_node(use) == b) { 3024 if( pinch->Opcode() == Op_Node && // Real pinch-point (not optimistic?) 3025 pinch->req() == 1 ) { // pinch not yet in block? 3026 pinch->del_req(0); // yank pointer to later-def, also set flag 3027 // Insert the pinch-point in the block just after the last use 3028 b->insert_node(pinch, b->find_node(use) + 1); 3029 _bb_end++; // Increase size scheduled region in block 3030 } 3031 3032 add_prec_edge_from_to(pinch,use); 3033 } 3034 } 3035 3036 // We insert antidependences between the reads and following write of 3037 // allocated registers to prevent illegal code motion. Hopefully, the 3038 // number of added references should be fairly small, especially as we 3039 // are only adding references within the current basic block. 3040 void Scheduling::ComputeRegisterAntidependencies(Block *b) { 3041 3042 #ifdef ASSERT 3043 verify_good_schedule(b,"before block local scheduling"); 3044 #endif 3045 3046 // A valid schedule, for each register independently, is an endless cycle 3047 // of: a def, then some uses (connected to the def by true dependencies), 3048 // then some kills (defs with no uses), finally the cycle repeats with a new 3049 // def. The uses are allowed to float relative to each other, as are the 3050 // kills. No use is allowed to slide past a kill (or def). This requires 3051 // antidependencies between all uses of a single def and all kills that 3052 // follow, up to the next def. More edges are redundant, because later defs 3053 // & kills are already serialized with true or antidependencies. To keep 3054 // the edge count down, we add a 'pinch point' node if there's more than 3055 // one use or more than one kill/def. 3056 3057 // We add dependencies in one bottom-up pass. 3058 3059 // For each instruction we handle it's DEFs/KILLs, then it's USEs. 3060 3061 // For each DEF/KILL, we check to see if there's a prior DEF/KILL for this 3062 // register. If not, we record the DEF/KILL in _reg_node, the 3063 // register-to-def mapping. If there is a prior DEF/KILL, we insert a 3064 // "pinch point", a new Node that's in the graph but not in the block. 3065 // We put edges from the prior and current DEF/KILLs to the pinch point. 3066 // We put the pinch point in _reg_node. If there's already a pinch point 3067 // we merely add an edge from the current DEF/KILL to the pinch point. 3068 3069 // After doing the DEF/KILLs, we handle USEs. For each used register, we 3070 // put an edge from the pinch point to the USE. 3071 3072 // To be expedient, the _reg_node array is pre-allocated for the whole 3073 // compilation. _reg_node is lazily initialized; it either contains a null, 3074 // or a valid def/kill/pinch-point, or a leftover node from some prior 3075 // block. Leftover node from some prior block is treated like a null (no 3076 // prior def, so no anti-dependence needed). Valid def is distinguished by 3077 // it being in the current block. 3078 bool fat_proj_seen = false; 3079 uint last_safept = _bb_end-1; 3080 Node* end_node = (_bb_end-1 >= _bb_start) ? b->get_node(last_safept) : nullptr; 3081 Node* last_safept_node = end_node; 3082 for( uint i = _bb_end-1; i >= _bb_start; i-- ) { 3083 Node *n = b->get_node(i); 3084 int is_def = n->outcnt(); // def if some uses prior to adding precedence edges 3085 if( n->is_MachProj() && n->ideal_reg() == MachProjNode::fat_proj ) { 3086 // Fat-proj kills a slew of registers 3087 // This can add edges to 'n' and obscure whether or not it was a def, 3088 // hence the is_def flag. 3089 fat_proj_seen = true; 3090 RegMaskIterator rmi(n->out_RegMask()); 3091 while (rmi.has_next()) { 3092 OptoReg::Name kill = rmi.next(); 3093 anti_do_def(b, n, kill, is_def); 3094 } 3095 } else { 3096 // Get DEF'd registers the normal way 3097 anti_do_def( b, n, _regalloc->get_reg_first(n), is_def ); 3098 anti_do_def( b, n, _regalloc->get_reg_second(n), is_def ); 3099 } 3100 3101 // Kill projections on a branch should appear to occur on the 3102 // branch, not afterwards, so grab the masks from the projections 3103 // and process them. 3104 if (n->is_MachBranch() || (n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_Jump)) { 3105 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3106 Node* use = n->fast_out(i); 3107 if (use->is_Proj()) { 3108 RegMaskIterator rmi(use->out_RegMask()); 3109 while (rmi.has_next()) { 3110 OptoReg::Name kill = rmi.next(); 3111 anti_do_def(b, n, kill, false); 3112 } 3113 } 3114 } 3115 } 3116 3117 // Check each register used by this instruction for a following DEF/KILL 3118 // that must occur afterward and requires an anti-dependence edge. 3119 for( uint j=0; j<n->req(); j++ ) { 3120 Node *def = n->in(j); 3121 if( def ) { 3122 assert( !def->is_MachProj() || def->ideal_reg() != MachProjNode::fat_proj, "" ); 3123 anti_do_use( b, n, _regalloc->get_reg_first(def) ); 3124 anti_do_use( b, n, _regalloc->get_reg_second(def) ); 3125 } 3126 } 3127 // Do not allow defs of new derived values to float above GC 3128 // points unless the base is definitely available at the GC point. 3129 3130 Node *m = b->get_node(i); 3131 3132 // Add precedence edge from following safepoint to use of derived pointer 3133 if( last_safept_node != end_node && 3134 m != last_safept_node) { 3135 for (uint k = 1; k < m->req(); k++) { 3136 const Type *t = m->in(k)->bottom_type(); 3137 if( t->isa_oop_ptr() && 3138 t->is_ptr()->offset() != 0 ) { 3139 last_safept_node->add_prec( m ); 3140 break; 3141 } 3142 } 3143 } 3144 3145 if( n->jvms() ) { // Precedence edge from derived to safept 3146 // Check if last_safept_node was moved by pinch-point insertion in anti_do_use() 3147 if( b->get_node(last_safept) != last_safept_node ) { 3148 last_safept = b->find_node(last_safept_node); 3149 } 3150 for( uint j=last_safept; j > i; j-- ) { 3151 Node *mach = b->get_node(j); 3152 if( mach->is_Mach() && mach->as_Mach()->ideal_Opcode() == Op_AddP ) 3153 mach->add_prec( n ); 3154 } 3155 last_safept = i; 3156 last_safept_node = m; 3157 } 3158 } 3159 3160 if (fat_proj_seen) { 3161 // Garbage collect pinch nodes that were not consumed. 3162 // They are usually created by a fat kill MachProj for a call. 3163 garbage_collect_pinch_nodes(); 3164 } 3165 } 3166 3167 // Garbage collect pinch nodes for reuse by other blocks. 3168 // 3169 // The block scheduler's insertion of anti-dependence 3170 // edges creates many pinch nodes when the block contains 3171 // 2 or more Calls. A pinch node is used to prevent a 3172 // combinatorial explosion of edges. If a set of kills for a 3173 // register is anti-dependent on a set of uses (or defs), rather 3174 // than adding an edge in the graph between each pair of kill 3175 // and use (or def), a pinch is inserted between them: 3176 // 3177 // use1 use2 use3 3178 // \ | / 3179 // \ | / 3180 // pinch 3181 // / | \ 3182 // / | \ 3183 // kill1 kill2 kill3 3184 // 3185 // One pinch node is created per register killed when 3186 // the second call is encountered during a backwards pass 3187 // over the block. Most of these pinch nodes are never 3188 // wired into the graph because the register is never 3189 // used or def'ed in the block. 3190 // 3191 void Scheduling::garbage_collect_pinch_nodes() { 3192 #ifndef PRODUCT 3193 if (_cfg->C->trace_opto_output()) tty->print("Reclaimed pinch nodes:"); 3194 #endif 3195 int trace_cnt = 0; 3196 for (uint k = 0; k < _reg_node.max(); k++) { 3197 Node* pinch = _reg_node[k]; 3198 if ((pinch != nullptr) && pinch->Opcode() == Op_Node && 3199 // no predecence input edges 3200 (pinch->req() == pinch->len() || pinch->in(pinch->req()) == nullptr) ) { 3201 cleanup_pinch(pinch); 3202 _pinch_free_list.push(pinch); 3203 _reg_node.map(k, nullptr); 3204 #ifndef PRODUCT 3205 if (_cfg->C->trace_opto_output()) { 3206 trace_cnt++; 3207 if (trace_cnt > 40) { 3208 tty->print("\n"); 3209 trace_cnt = 0; 3210 } 3211 tty->print(" %d", pinch->_idx); 3212 } 3213 #endif 3214 } 3215 } 3216 #ifndef PRODUCT 3217 if (_cfg->C->trace_opto_output()) tty->print("\n"); 3218 #endif 3219 } 3220 3221 // Clean up a pinch node for reuse. 3222 void Scheduling::cleanup_pinch( Node *pinch ) { 3223 assert (pinch && pinch->Opcode() == Op_Node && pinch->req() == 1, "just checking"); 3224 3225 for (DUIterator_Last imin, i = pinch->last_outs(imin); i >= imin; ) { 3226 Node* use = pinch->last_out(i); 3227 uint uses_found = 0; 3228 for (uint j = use->req(); j < use->len(); j++) { 3229 if (use->in(j) == pinch) { 3230 use->rm_prec(j); 3231 uses_found++; 3232 } 3233 } 3234 assert(uses_found > 0, "must be a precedence edge"); 3235 i -= uses_found; // we deleted 1 or more copies of this edge 3236 } 3237 // May have a later_def entry 3238 pinch->set_req(0, nullptr); 3239 } 3240 3241 #ifndef PRODUCT 3242 3243 void Scheduling::dump_available() const { 3244 tty->print("#Availist "); 3245 for (uint i = 0; i < _available.size(); i++) 3246 tty->print(" N%d/l%d", _available[i]->_idx,_current_latency[_available[i]->_idx]); 3247 tty->cr(); 3248 } 3249 3250 // Print Scheduling Statistics 3251 void Scheduling::print_statistics() { 3252 // Print the size added by nops for bundling 3253 tty->print("Nops added %d bytes to total of %d bytes", 3254 _total_nop_size, _total_method_size); 3255 if (_total_method_size > 0) 3256 tty->print(", for %.2f%%", 3257 ((double)_total_nop_size) / ((double) _total_method_size) * 100.0); 3258 tty->print("\n"); 3259 3260 // Print the number of branch shadows filled 3261 if (Pipeline::_branch_has_delay_slot) { 3262 tty->print("Of %d branches, %d had unconditional delay slots filled", 3263 _total_branches, _total_unconditional_delays); 3264 if (_total_branches > 0) 3265 tty->print(", for %.2f%%", 3266 ((double)_total_unconditional_delays) / ((double)_total_branches) * 100.0); 3267 tty->print("\n"); 3268 } 3269 3270 uint total_instructions = 0, total_bundles = 0; 3271 3272 for (uint i = 1; i <= Pipeline::_max_instrs_per_cycle; i++) { 3273 uint bundle_count = _total_instructions_per_bundle[i]; 3274 total_instructions += bundle_count * i; 3275 total_bundles += bundle_count; 3276 } 3277 3278 if (total_bundles > 0) 3279 tty->print("Average ILP (excluding nops) is %.2f\n", 3280 ((double)total_instructions) / ((double)total_bundles)); 3281 } 3282 #endif 3283 3284 //-----------------------init_scratch_buffer_blob------------------------------ 3285 // Construct a temporary BufferBlob and cache it for this compile. 3286 void PhaseOutput::init_scratch_buffer_blob(int const_size) { 3287 // If there is already a scratch buffer blob allocated and the 3288 // constant section is big enough, use it. Otherwise free the 3289 // current and allocate a new one. 3290 BufferBlob* blob = scratch_buffer_blob(); 3291 if ((blob != nullptr) && (const_size <= _scratch_const_size)) { 3292 // Use the current blob. 3293 } else { 3294 if (blob != nullptr) { 3295 BufferBlob::free(blob); 3296 } 3297 3298 ResourceMark rm; 3299 _scratch_const_size = const_size; 3300 int size = C2Compiler::initial_code_buffer_size(const_size); 3301 blob = BufferBlob::create("Compile::scratch_buffer", size); 3302 // Record the buffer blob for next time. 3303 set_scratch_buffer_blob(blob); 3304 // Have we run out of code space? 3305 if (scratch_buffer_blob() == nullptr) { 3306 // Let CompilerBroker disable further compilations. 3307 C->record_failure("Not enough space for scratch buffer in CodeCache"); 3308 return; 3309 } 3310 } 3311 3312 // Initialize the relocation buffers 3313 relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size; 3314 set_scratch_locs_memory(locs_buf); 3315 } 3316 3317 3318 //-----------------------scratch_emit_size------------------------------------- 3319 // Helper function that computes size by emitting code 3320 uint PhaseOutput::scratch_emit_size(const Node* n) { 3321 // Start scratch_emit_size section. 3322 set_in_scratch_emit_size(true); 3323 3324 // Emit into a trash buffer and count bytes emitted. 3325 // This is a pretty expensive way to compute a size, 3326 // but it works well enough if seldom used. 3327 // All common fixed-size instructions are given a size 3328 // method by the AD file. 3329 // Note that the scratch buffer blob and locs memory are 3330 // allocated at the beginning of the compile task, and 3331 // may be shared by several calls to scratch_emit_size. 3332 // The allocation of the scratch buffer blob is particularly 3333 // expensive, since it has to grab the code cache lock. 3334 BufferBlob* blob = this->scratch_buffer_blob(); 3335 assert(blob != nullptr, "Initialize BufferBlob at start"); 3336 assert(blob->size() > MAX_inst_size, "sanity"); 3337 relocInfo* locs_buf = scratch_locs_memory(); 3338 address blob_begin = blob->content_begin(); 3339 address blob_end = (address)locs_buf; 3340 assert(blob->contains(blob_end), "sanity"); 3341 CodeBuffer buf(blob_begin, blob_end - blob_begin); 3342 buf.initialize_consts_size(_scratch_const_size); 3343 buf.initialize_stubs_size(MAX_stubs_size); 3344 assert(locs_buf != nullptr, "sanity"); 3345 int lsize = MAX_locs_size / 3; 3346 buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize); 3347 buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize); 3348 buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize); 3349 // Mark as scratch buffer. 3350 buf.consts()->set_scratch_emit(); 3351 buf.insts()->set_scratch_emit(); 3352 buf.stubs()->set_scratch_emit(); 3353 3354 // Do the emission. 3355 3356 Label fakeL; // Fake label for branch instructions. 3357 Label* saveL = nullptr; 3358 uint save_bnum = 0; 3359 bool is_branch = n->is_MachBranch(); 3360 if (is_branch) { 3361 MacroAssembler masm(&buf); 3362 masm.bind(fakeL); 3363 n->as_MachBranch()->save_label(&saveL, &save_bnum); 3364 n->as_MachBranch()->label_set(&fakeL, 0); 3365 } 3366 n->emit(buf, C->regalloc()); 3367 3368 // Emitting into the scratch buffer should not fail 3369 assert (!C->failing(), "Must not have pending failure. Reason is: %s", C->failure_reason()); 3370 3371 if (is_branch) // Restore label. 3372 n->as_MachBranch()->label_set(saveL, save_bnum); 3373 3374 // End scratch_emit_size section. 3375 set_in_scratch_emit_size(false); 3376 3377 return buf.insts_size(); 3378 } 3379 3380 void PhaseOutput::install() { 3381 if (!C->should_install_code()) { 3382 return; 3383 } else if (C->stub_function() != nullptr) { 3384 install_stub(C->stub_name()); 3385 } else { 3386 install_code(C->method(), 3387 C->entry_bci(), 3388 CompileBroker::compiler2(), 3389 C->has_unsafe_access(), 3390 SharedRuntime::is_wide_vector(C->max_vector_size()), 3391 C->rtm_state()); 3392 } 3393 } 3394 3395 void PhaseOutput::install_code(ciMethod* target, 3396 int entry_bci, 3397 AbstractCompiler* compiler, 3398 bool has_unsafe_access, 3399 bool has_wide_vectors, 3400 RTMState rtm_state) { 3401 // Check if we want to skip execution of all compiled code. 3402 { 3403 #ifndef PRODUCT 3404 if (OptoNoExecute) { 3405 C->record_method_not_compilable("+OptoNoExecute"); // Flag as failed 3406 return; 3407 } 3408 #endif 3409 Compile::TracePhase tp("install_code", &timers[_t_registerMethod]); 3410 3411 if (C->is_osr_compilation()) { 3412 _code_offsets.set_value(CodeOffsets::Verified_Entry, 0); 3413 _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size); 3414 } else { 3415 if (!target->is_static()) { 3416 // The UEP of an nmethod ensures that the VEP is padded. However, the padding of the UEP is placed 3417 // before the inline cache check, so we don't have to execute any nop instructions when dispatching 3418 // through the UEP, yet we can ensure that the VEP is aligned appropriately. 3419 _code_offsets.set_value(CodeOffsets::Entry, _first_block_size - MacroAssembler::ic_check_size()); 3420 } 3421 _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size); 3422 _code_offsets.set_value(CodeOffsets::OSR_Entry, 0); 3423 } 3424 3425 C->env()->register_method(target, 3426 entry_bci, 3427 &_code_offsets, 3428 _orig_pc_slot_offset_in_bytes, 3429 code_buffer(), 3430 frame_size_in_words(), 3431 oop_map_set(), 3432 &_handler_table, 3433 inc_table(), 3434 compiler, 3435 has_unsafe_access, 3436 SharedRuntime::is_wide_vector(C->max_vector_size()), 3437 C->has_monitors(), 3438 0, 3439 C->rtm_state()); 3440 3441 if (C->log() != nullptr) { // Print code cache state into compiler log 3442 C->log()->code_cache_state(); 3443 } 3444 } 3445 } 3446 void PhaseOutput::install_stub(const char* stub_name) { 3447 // Entry point will be accessed using stub_entry_point(); 3448 if (code_buffer() == nullptr) { 3449 Matcher::soft_match_failure(); 3450 } else { 3451 if (PrintAssembly && (WizardMode || Verbose)) 3452 tty->print_cr("### Stub::%s", stub_name); 3453 3454 if (!C->failing()) { 3455 assert(C->fixed_slots() == 0, "no fixed slots used for runtime stubs"); 3456 3457 // Make the NMethod 3458 // For now we mark the frame as never safe for profile stackwalking 3459 RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name, 3460 code_buffer(), 3461 CodeOffsets::frame_never_safe, 3462 // _code_offsets.value(CodeOffsets::Frame_Complete), 3463 frame_size_in_words(), 3464 oop_map_set(), 3465 false); 3466 assert(rs != nullptr && rs->is_runtime_stub(), "sanity check"); 3467 3468 C->set_stub_entry_point(rs->entry_point()); 3469 } 3470 } 3471 } 3472 3473 // Support for bundling info 3474 Bundle* PhaseOutput::node_bundling(const Node *n) { 3475 assert(valid_bundle_info(n), "oob"); 3476 return &_node_bundling_base[n->_idx]; 3477 } 3478 3479 bool PhaseOutput::valid_bundle_info(const Node *n) { 3480 return (_node_bundling_limit > n->_idx); 3481 } 3482 3483 //------------------------------frame_size_in_words----------------------------- 3484 // frame_slots in units of words 3485 int PhaseOutput::frame_size_in_words() const { 3486 // shift is 0 in LP32 and 1 in LP64 3487 const int shift = (LogBytesPerWord - LogBytesPerInt); 3488 int words = _frame_slots >> shift; 3489 assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" ); 3490 return words; 3491 } 3492 3493 // To bang the stack of this compiled method we use the stack size 3494 // that the interpreter would need in case of a deoptimization. This 3495 // removes the need to bang the stack in the deoptimization blob which 3496 // in turn simplifies stack overflow handling. 3497 int PhaseOutput::bang_size_in_bytes() const { 3498 return MAX2(frame_size_in_bytes() + os::extra_bang_size_in_bytes(), C->interpreter_frame_size()); 3499 } 3500 3501 //------------------------------dump_asm--------------------------------------- 3502 // Dump formatted assembly 3503 #if defined(SUPPORT_OPTO_ASSEMBLY) 3504 void PhaseOutput::dump_asm_on(outputStream* st, int* pcs, uint pc_limit) { 3505 3506 int pc_digits = 3; // #chars required for pc 3507 int sb_chars = 3; // #chars for "start bundle" indicator 3508 int tab_size = 8; 3509 if (pcs != nullptr) { 3510 int max_pc = 0; 3511 for (uint i = 0; i < pc_limit; i++) { 3512 max_pc = (max_pc < pcs[i]) ? pcs[i] : max_pc; 3513 } 3514 pc_digits = ((max_pc < 4096) ? 3 : ((max_pc < 65536) ? 4 : ((max_pc < 65536*256) ? 6 : 8))); // #chars required for pc 3515 } 3516 int prefix_len = ((pc_digits + sb_chars + tab_size - 1)/tab_size)*tab_size; 3517 3518 bool cut_short = false; 3519 st->print_cr("#"); 3520 st->print("# "); C->tf()->dump_on(st); st->cr(); 3521 st->print_cr("#"); 3522 3523 // For all blocks 3524 int pc = 0x0; // Program counter 3525 char starts_bundle = ' '; 3526 C->regalloc()->dump_frame(); 3527 3528 Node *n = nullptr; 3529 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) { 3530 if (VMThread::should_terminate()) { 3531 cut_short = true; 3532 break; 3533 } 3534 Block* block = C->cfg()->get_block(i); 3535 if (block->is_connector() && !Verbose) { 3536 continue; 3537 } 3538 n = block->head(); 3539 if ((pcs != nullptr) && (n->_idx < pc_limit)) { 3540 pc = pcs[n->_idx]; 3541 st->print("%*.*x", pc_digits, pc_digits, pc); 3542 } 3543 st->fill_to(prefix_len); 3544 block->dump_head(C->cfg(), st); 3545 if (block->is_connector()) { 3546 st->fill_to(prefix_len); 3547 st->print_cr("# Empty connector block"); 3548 } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) { 3549 st->fill_to(prefix_len); 3550 st->print_cr("# Block is sole successor of call"); 3551 } 3552 3553 // For all instructions 3554 Node *delay = nullptr; 3555 for (uint j = 0; j < block->number_of_nodes(); j++) { 3556 if (VMThread::should_terminate()) { 3557 cut_short = true; 3558 break; 3559 } 3560 n = block->get_node(j); 3561 if (valid_bundle_info(n)) { 3562 Bundle* bundle = node_bundling(n); 3563 if (bundle->used_in_unconditional_delay()) { 3564 delay = n; 3565 continue; 3566 } 3567 if (bundle->starts_bundle()) { 3568 starts_bundle = '+'; 3569 } 3570 } 3571 3572 if (WizardMode) { 3573 n->dump(); 3574 } 3575 3576 if( !n->is_Region() && // Dont print in the Assembly 3577 !n->is_Phi() && // a few noisely useless nodes 3578 !n->is_Proj() && 3579 !n->is_MachTemp() && 3580 !n->is_SafePointScalarObject() && 3581 !n->is_Catch() && // Would be nice to print exception table targets 3582 !n->is_MergeMem() && // Not very interesting 3583 !n->is_top() && // Debug info table constants 3584 !(n->is_Con() && !n->is_Mach())// Debug info table constants 3585 ) { 3586 if ((pcs != nullptr) && (n->_idx < pc_limit)) { 3587 pc = pcs[n->_idx]; 3588 st->print("%*.*x", pc_digits, pc_digits, pc); 3589 } else { 3590 st->fill_to(pc_digits); 3591 } 3592 st->print(" %c ", starts_bundle); 3593 starts_bundle = ' '; 3594 st->fill_to(prefix_len); 3595 n->format(C->regalloc(), st); 3596 st->cr(); 3597 } 3598 3599 // If we have an instruction with a delay slot, and have seen a delay, 3600 // then back up and print it 3601 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) { 3602 // Coverity finding - Explicit null dereferenced. 3603 guarantee(delay != nullptr, "no unconditional delay instruction"); 3604 if (WizardMode) delay->dump(); 3605 3606 if (node_bundling(delay)->starts_bundle()) 3607 starts_bundle = '+'; 3608 if ((pcs != nullptr) && (n->_idx < pc_limit)) { 3609 pc = pcs[n->_idx]; 3610 st->print("%*.*x", pc_digits, pc_digits, pc); 3611 } else { 3612 st->fill_to(pc_digits); 3613 } 3614 st->print(" %c ", starts_bundle); 3615 starts_bundle = ' '; 3616 st->fill_to(prefix_len); 3617 delay->format(C->regalloc(), st); 3618 st->cr(); 3619 delay = nullptr; 3620 } 3621 3622 // Dump the exception table as well 3623 if( n->is_Catch() && (Verbose || WizardMode) ) { 3624 // Print the exception table for this offset 3625 _handler_table.print_subtable_for(pc); 3626 } 3627 st->bol(); // Make sure we start on a new line 3628 } 3629 st->cr(); // one empty line between blocks 3630 assert(cut_short || delay == nullptr, "no unconditional delay branch"); 3631 } // End of per-block dump 3632 3633 if (cut_short) st->print_cr("*** disassembly is cut short ***"); 3634 } 3635 #endif 3636 3637 #ifndef PRODUCT 3638 void PhaseOutput::print_statistics() { 3639 Scheduling::print_statistics(); 3640 } 3641 #endif