1 /* 2 * Copyright (c) 1998, 2014, 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 "code/compiledIC.hpp" 28 #include "code/debugInfo.hpp" 29 #include "code/debugInfoRec.hpp" 30 #include "compiler/compileBroker.hpp" 31 #include "compiler/oopMap.hpp" 32 #include "memory/allocation.inline.hpp" 33 #include "opto/ad.hpp" 34 #include "opto/callnode.hpp" 35 #include "opto/cfgnode.hpp" 36 #include "opto/locknode.hpp" 37 #include "opto/machnode.hpp" 38 #include "opto/optoreg.hpp" 39 #include "opto/output.hpp" 40 #include "opto/regalloc.hpp" 41 #include "opto/runtime.hpp" 42 #include "opto/subnode.hpp" 43 #include "opto/type.hpp" 44 #include "runtime/handles.inline.hpp" 45 #include "utilities/xmlstream.hpp" 46 47 #ifndef PRODUCT 48 #define DEBUG_ARG(x) , x 49 #else 50 #define DEBUG_ARG(x) 51 #endif 52 53 // Convert Nodes to instruction bits and pass off to the VM 54 void Compile::Output() { 55 // RootNode goes 56 assert( _cfg->get_root_block()->number_of_nodes() == 0, "" ); 57 58 // The number of new nodes (mostly MachNop) is proportional to 59 // the number of java calls and inner loops which are aligned. 60 if ( C->check_node_count((NodeLimitFudgeFactor + C->java_calls()*3 + 61 C->inner_loops()*(OptoLoopAlignment-1)), 62 "out of nodes before code generation" ) ) { 63 return; 64 } 65 // Make sure I can find the Start Node 66 Block *entry = _cfg->get_block(1); 67 Block *broot = _cfg->get_root_block(); 68 69 const StartNode *start = entry->head()->as_Start(); 70 71 // Replace StartNode with prolog 72 MachPrologNode *prolog = new MachPrologNode(); 73 entry->map_node(prolog, 0); 74 _cfg->map_node_to_block(prolog, entry); 75 _cfg->unmap_node_from_block(start); // start is no longer in any block 76 77 // Virtual methods need an unverified entry point 78 79 if( is_osr_compilation() ) { 80 if( PoisonOSREntry ) { 81 // TODO: Should use a ShouldNotReachHereNode... 82 _cfg->insert( broot, 0, new MachBreakpointNode() ); 83 } 84 } else { 85 if( _method && !_method->flags().is_static() ) { 86 // Insert unvalidated entry point 87 _cfg->insert( broot, 0, new MachUEPNode() ); 88 } 89 90 } 91 92 93 // Break before main entry point 94 if( (_method && _method->break_at_execute()) 95 #ifndef PRODUCT 96 ||(OptoBreakpoint && is_method_compilation()) 97 ||(OptoBreakpointOSR && is_osr_compilation()) 98 ||(OptoBreakpointC2R && !_method) 99 #endif 100 ) { 101 // checking for _method means that OptoBreakpoint does not apply to 102 // runtime stubs or frame converters 103 _cfg->insert( entry, 1, new MachBreakpointNode() ); 104 } 105 106 // Insert epilogs before every return 107 for (uint i = 0; i < _cfg->number_of_blocks(); i++) { 108 Block* block = _cfg->get_block(i); 109 if (!block->is_connector() && block->non_connector_successor(0) == _cfg->get_root_block()) { // Found a program exit point? 110 Node* m = block->end(); 111 if (m->is_Mach() && m->as_Mach()->ideal_Opcode() != Op_Halt) { 112 MachEpilogNode* epilog = new MachEpilogNode(m->as_Mach()->ideal_Opcode() == Op_Return); 113 block->add_inst(epilog); 114 _cfg->map_node_to_block(epilog, block); 115 } 116 } 117 } 118 119 # ifdef ENABLE_ZAP_DEAD_LOCALS 120 if (ZapDeadCompiledLocals) { 121 Insert_zap_nodes(); 122 } 123 # endif 124 125 uint* blk_starts = NEW_RESOURCE_ARRAY(uint, _cfg->number_of_blocks() + 1); 126 blk_starts[0] = 0; 127 128 // Initialize code buffer and process short branches. 129 CodeBuffer* cb = init_buffer(blk_starts); 130 131 if (cb == NULL || failing()) { 132 return; 133 } 134 135 ScheduleAndBundle(); 136 137 #ifndef PRODUCT 138 if (trace_opto_output()) { 139 tty->print("\n---- After ScheduleAndBundle ----\n"); 140 for (uint i = 0; i < _cfg->number_of_blocks(); i++) { 141 tty->print("\nBB#%03d:\n", i); 142 Block* block = _cfg->get_block(i); 143 for (uint j = 0; j < block->number_of_nodes(); j++) { 144 Node* n = block->get_node(j); 145 OptoReg::Name reg = _regalloc->get_reg_first(n); 146 tty->print(" %-6s ", reg >= 0 && reg < REG_COUNT ? Matcher::regName[reg] : ""); 147 n->dump(); 148 } 149 } 150 } 151 #endif 152 153 if (failing()) { 154 return; 155 } 156 157 BuildOopMaps(); 158 159 if (failing()) { 160 return; 161 } 162 163 fill_buffer(cb, blk_starts); 164 } 165 166 bool Compile::need_stack_bang(int frame_size_in_bytes) const { 167 // Determine if we need to generate a stack overflow check. 168 // Do it if the method is not a stub function and 169 // has java calls or has frame size > vm_page_size/8. 170 // The debug VM checks that deoptimization doesn't trigger an 171 // unexpected stack overflow (compiled method stack banging should 172 // guarantee it doesn't happen) so we always need the stack bang in 173 // a debug VM. 174 return (UseStackBanging && stub_function() == NULL && 175 (has_java_calls() || frame_size_in_bytes > os::vm_page_size()>>3 176 DEBUG_ONLY(|| true))); 177 } 178 179 bool Compile::need_register_stack_bang() const { 180 // Determine if we need to generate a register stack overflow check. 181 // This is only used on architectures which have split register 182 // and memory stacks (ie. IA64). 183 // Bang if the method is not a stub function and has java calls 184 return (stub_function() == NULL && has_java_calls()); 185 } 186 187 # ifdef ENABLE_ZAP_DEAD_LOCALS 188 189 190 // In order to catch compiler oop-map bugs, we have implemented 191 // a debugging mode called ZapDeadCompilerLocals. 192 // This mode causes the compiler to insert a call to a runtime routine, 193 // "zap_dead_locals", right before each place in compiled code 194 // that could potentially be a gc-point (i.e., a safepoint or oop map point). 195 // The runtime routine checks that locations mapped as oops are really 196 // oops, that locations mapped as values do not look like oops, 197 // and that locations mapped as dead are not used later 198 // (by zapping them to an invalid address). 199 200 int Compile::_CompiledZap_count = 0; 201 202 void Compile::Insert_zap_nodes() { 203 bool skip = false; 204 205 206 // Dink with static counts because code code without the extra 207 // runtime calls is MUCH faster for debugging purposes 208 209 if ( CompileZapFirst == 0 ) ; // nothing special 210 else if ( CompileZapFirst > CompiledZap_count() ) skip = true; 211 else if ( CompileZapFirst == CompiledZap_count() ) 212 warning("starting zap compilation after skipping"); 213 214 if ( CompileZapLast == -1 ) ; // nothing special 215 else if ( CompileZapLast < CompiledZap_count() ) skip = true; 216 else if ( CompileZapLast == CompiledZap_count() ) 217 warning("about to compile last zap"); 218 219 ++_CompiledZap_count; // counts skipped zaps, too 220 221 if ( skip ) return; 222 223 224 if ( _method == NULL ) 225 return; // no safepoints/oopmaps emitted for calls in stubs,so we don't care 226 227 // Insert call to zap runtime stub before every node with an oop map 228 for( uint i=0; i<_cfg->number_of_blocks(); i++ ) { 229 Block *b = _cfg->get_block(i); 230 for ( uint j = 0; j < b->number_of_nodes(); ++j ) { 231 Node *n = b->get_node(j); 232 233 // Determining if we should insert a zap-a-lot node in output. 234 // We do that for all nodes that has oopmap info, except for calls 235 // to allocation. Calls to allocation passes in the old top-of-eden pointer 236 // and expect the C code to reset it. Hence, there can be no safepoints between 237 // the inlined-allocation and the call to new_Java, etc. 238 // We also cannot zap monitor calls, as they must hold the microlock 239 // during the call to Zap, which also wants to grab the microlock. 240 bool insert = n->is_MachSafePoint() && (n->as_MachSafePoint()->oop_map() != NULL); 241 if ( insert ) { // it is MachSafePoint 242 if ( !n->is_MachCall() ) { 243 insert = false; 244 } else if ( n->is_MachCall() ) { 245 MachCallNode* call = n->as_MachCall(); 246 if (call->entry_point() == OptoRuntime::new_instance_Java() || 247 call->entry_point() == OptoRuntime::new_array_Java() || 248 call->entry_point() == OptoRuntime::multianewarray2_Java() || 249 call->entry_point() == OptoRuntime::multianewarray3_Java() || 250 call->entry_point() == OptoRuntime::multianewarray4_Java() || 251 call->entry_point() == OptoRuntime::multianewarray5_Java() || 252 call->entry_point() == OptoRuntime::slow_arraycopy_Java() || 253 call->entry_point() == OptoRuntime::complete_monitor_locking_Java() 254 ) { 255 insert = false; 256 } 257 } 258 if (insert) { 259 Node *zap = call_zap_node(n->as_MachSafePoint(), i); 260 b->insert_node(zap, j); 261 _cfg->map_node_to_block(zap, b); 262 ++j; 263 } 264 } 265 } 266 } 267 } 268 269 270 Node* Compile::call_zap_node(MachSafePointNode* node_to_check, int block_no) { 271 const TypeFunc *tf = OptoRuntime::zap_dead_locals_Type(); 272 CallStaticJavaNode* ideal_node = 273 new CallStaticJavaNode( tf, 274 OptoRuntime::zap_dead_locals_stub(_method->flags().is_native()), 275 "call zap dead locals stub", 0, TypePtr::BOTTOM); 276 // We need to copy the OopMap from the site we're zapping at. 277 // We have to make a copy, because the zap site might not be 278 // a call site, and zap_dead is a call site. 279 OopMap* clone = node_to_check->oop_map()->deep_copy(); 280 281 // Add the cloned OopMap to the zap node 282 ideal_node->set_oop_map(clone); 283 return _matcher->match_sfpt(ideal_node); 284 } 285 286 bool Compile::is_node_getting_a_safepoint( Node* n) { 287 // This code duplicates the logic prior to the call of add_safepoint 288 // below in this file. 289 if( n->is_MachSafePoint() ) return true; 290 return false; 291 } 292 293 # endif // ENABLE_ZAP_DEAD_LOCALS 294 295 // Compute the size of first NumberOfLoopInstrToAlign instructions at the top 296 // of a loop. When aligning a loop we need to provide enough instructions 297 // in cpu's fetch buffer to feed decoders. The loop alignment could be 298 // avoided if we have enough instructions in fetch buffer at the head of a loop. 299 // By default, the size is set to 999999 by Block's constructor so that 300 // a loop will be aligned if the size is not reset here. 301 // 302 // Note: Mach instructions could contain several HW instructions 303 // so the size is estimated only. 304 // 305 void Compile::compute_loop_first_inst_sizes() { 306 // The next condition is used to gate the loop alignment optimization. 307 // Don't aligned a loop if there are enough instructions at the head of a loop 308 // or alignment padding is larger then MaxLoopPad. By default, MaxLoopPad 309 // is equal to OptoLoopAlignment-1 except on new Intel cpus, where it is 310 // equal to 11 bytes which is the largest address NOP instruction. 311 if (MaxLoopPad < OptoLoopAlignment - 1) { 312 uint last_block = _cfg->number_of_blocks() - 1; 313 for (uint i = 1; i <= last_block; i++) { 314 Block* block = _cfg->get_block(i); 315 // Check the first loop's block which requires an alignment. 316 if (block->loop_alignment() > (uint)relocInfo::addr_unit()) { 317 uint sum_size = 0; 318 uint inst_cnt = NumberOfLoopInstrToAlign; 319 inst_cnt = block->compute_first_inst_size(sum_size, inst_cnt, _regalloc); 320 321 // Check subsequent fallthrough blocks if the loop's first 322 // block(s) does not have enough instructions. 323 Block *nb = block; 324 while(inst_cnt > 0 && 325 i < last_block && 326 !_cfg->get_block(i + 1)->has_loop_alignment() && 327 !nb->has_successor(block)) { 328 i++; 329 nb = _cfg->get_block(i); 330 inst_cnt = nb->compute_first_inst_size(sum_size, inst_cnt, _regalloc); 331 } // while( inst_cnt > 0 && i < last_block ) 332 333 block->set_first_inst_size(sum_size); 334 } // f( b->head()->is_Loop() ) 335 } // for( i <= last_block ) 336 } // if( MaxLoopPad < OptoLoopAlignment-1 ) 337 } 338 339 // The architecture description provides short branch variants for some long 340 // branch instructions. Replace eligible long branches with short branches. 341 void Compile::shorten_branches(uint* blk_starts, int& code_size, int& reloc_size, int& stub_size) { 342 // Compute size of each block, method size, and relocation information size 343 uint nblocks = _cfg->number_of_blocks(); 344 345 uint* jmp_offset = NEW_RESOURCE_ARRAY(uint,nblocks); 346 uint* jmp_size = NEW_RESOURCE_ARRAY(uint,nblocks); 347 int* jmp_nidx = NEW_RESOURCE_ARRAY(int ,nblocks); 348 349 // Collect worst case block paddings 350 int* block_worst_case_pad = NEW_RESOURCE_ARRAY(int, nblocks); 351 memset(block_worst_case_pad, 0, nblocks * sizeof(int)); 352 353 DEBUG_ONLY( uint *jmp_target = NEW_RESOURCE_ARRAY(uint,nblocks); ) 354 DEBUG_ONLY( uint *jmp_rule = NEW_RESOURCE_ARRAY(uint,nblocks); ) 355 356 bool has_short_branch_candidate = false; 357 358 // Initialize the sizes to 0 359 code_size = 0; // Size in bytes of generated code 360 stub_size = 0; // Size in bytes of all stub entries 361 // Size in bytes of all relocation entries, including those in local stubs. 362 // Start with 2-bytes of reloc info for the unvalidated entry point 363 reloc_size = 1; // Number of relocation entries 364 365 // Make three passes. The first computes pessimistic blk_starts, 366 // relative jmp_offset and reloc_size information. The second performs 367 // short branch substitution using the pessimistic sizing. The 368 // third inserts nops where needed. 369 370 // Step one, perform a pessimistic sizing pass. 371 uint last_call_adr = max_juint; 372 uint last_avoid_back_to_back_adr = max_juint; 373 uint nop_size = (new MachNopNode())->size(_regalloc); 374 for (uint i = 0; i < nblocks; i++) { // For all blocks 375 Block* block = _cfg->get_block(i); 376 377 // During short branch replacement, we store the relative (to blk_starts) 378 // offset of jump in jmp_offset, rather than the absolute offset of jump. 379 // This is so that we do not need to recompute sizes of all nodes when 380 // we compute correct blk_starts in our next sizing pass. 381 jmp_offset[i] = 0; 382 jmp_size[i] = 0; 383 jmp_nidx[i] = -1; 384 DEBUG_ONLY( jmp_target[i] = 0; ) 385 DEBUG_ONLY( jmp_rule[i] = 0; ) 386 387 // Sum all instruction sizes to compute block size 388 uint last_inst = block->number_of_nodes(); 389 uint blk_size = 0; 390 for (uint j = 0; j < last_inst; j++) { 391 Node* nj = block->get_node(j); 392 // Handle machine instruction nodes 393 if (nj->is_Mach()) { 394 MachNode *mach = nj->as_Mach(); 395 blk_size += (mach->alignment_required() - 1) * relocInfo::addr_unit(); // assume worst case padding 396 reloc_size += mach->reloc(); 397 if (mach->is_MachCall()) { 398 // add size information for trampoline stub 399 // class CallStubImpl is platform-specific and defined in the *.ad files. 400 stub_size += CallStubImpl::size_call_trampoline(); 401 reloc_size += CallStubImpl::reloc_call_trampoline(); 402 403 MachCallNode *mcall = mach->as_MachCall(); 404 // This destination address is NOT PC-relative 405 406 mcall->method_set((intptr_t)mcall->entry_point()); 407 408 if (mcall->is_MachCallJava() && mcall->as_MachCallJava()->_method) { 409 stub_size += CompiledStaticCall::to_interp_stub_size(); 410 reloc_size += CompiledStaticCall::reloc_to_interp_stub(); 411 } 412 } else if (mach->is_MachSafePoint()) { 413 // If call/safepoint are adjacent, account for possible 414 // nop to disambiguate the two safepoints. 415 // ScheduleAndBundle() can rearrange nodes in a block, 416 // check for all offsets inside this block. 417 if (last_call_adr >= blk_starts[i]) { 418 blk_size += nop_size; 419 } 420 } 421 if (mach->avoid_back_to_back(MachNode::AVOID_BEFORE)) { 422 // Nop is inserted between "avoid back to back" instructions. 423 // ScheduleAndBundle() can rearrange nodes in a block, 424 // check for all offsets inside this block. 425 if (last_avoid_back_to_back_adr >= blk_starts[i]) { 426 blk_size += nop_size; 427 } 428 } 429 if (mach->may_be_short_branch()) { 430 if (!nj->is_MachBranch()) { 431 #ifndef PRODUCT 432 nj->dump(3); 433 #endif 434 Unimplemented(); 435 } 436 assert(jmp_nidx[i] == -1, "block should have only one branch"); 437 jmp_offset[i] = blk_size; 438 jmp_size[i] = nj->size(_regalloc); 439 jmp_nidx[i] = j; 440 has_short_branch_candidate = true; 441 } 442 } 443 blk_size += nj->size(_regalloc); 444 // Remember end of call offset 445 if (nj->is_MachCall() && !nj->is_MachCallLeaf()) { 446 last_call_adr = blk_starts[i]+blk_size; 447 } 448 // Remember end of avoid_back_to_back offset 449 if (nj->is_Mach() && nj->as_Mach()->avoid_back_to_back(MachNode::AVOID_AFTER)) { 450 last_avoid_back_to_back_adr = blk_starts[i]+blk_size; 451 } 452 } 453 454 // When the next block starts a loop, we may insert pad NOP 455 // instructions. Since we cannot know our future alignment, 456 // assume the worst. 457 if (i < nblocks - 1) { 458 Block* nb = _cfg->get_block(i + 1); 459 int max_loop_pad = nb->code_alignment()-relocInfo::addr_unit(); 460 if (max_loop_pad > 0) { 461 assert(is_power_of_2(max_loop_pad+relocInfo::addr_unit()), ""); 462 // Adjust last_call_adr and/or last_avoid_back_to_back_adr. 463 // If either is the last instruction in this block, bump by 464 // max_loop_pad in lock-step with blk_size, so sizing 465 // calculations in subsequent blocks still can conservatively 466 // detect that it may the last instruction in this block. 467 if (last_call_adr == blk_starts[i]+blk_size) { 468 last_call_adr += max_loop_pad; 469 } 470 if (last_avoid_back_to_back_adr == blk_starts[i]+blk_size) { 471 last_avoid_back_to_back_adr += max_loop_pad; 472 } 473 blk_size += max_loop_pad; 474 block_worst_case_pad[i + 1] = max_loop_pad; 475 } 476 } 477 478 // Save block size; update total method size 479 blk_starts[i+1] = blk_starts[i]+blk_size; 480 } 481 482 // Step two, replace eligible long jumps. 483 bool progress = true; 484 uint last_may_be_short_branch_adr = max_juint; 485 while (has_short_branch_candidate && progress) { 486 progress = false; 487 has_short_branch_candidate = false; 488 int adjust_block_start = 0; 489 for (uint i = 0; i < nblocks; i++) { 490 Block* block = _cfg->get_block(i); 491 int idx = jmp_nidx[i]; 492 MachNode* mach = (idx == -1) ? NULL: block->get_node(idx)->as_Mach(); 493 if (mach != NULL && mach->may_be_short_branch()) { 494 #ifdef ASSERT 495 assert(jmp_size[i] > 0 && mach->is_MachBranch(), "sanity"); 496 int j; 497 // Find the branch; ignore trailing NOPs. 498 for (j = block->number_of_nodes()-1; j>=0; j--) { 499 Node* n = block->get_node(j); 500 if (!n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con) 501 break; 502 } 503 assert(j >= 0 && j == idx && block->get_node(j) == (Node*)mach, "sanity"); 504 #endif 505 int br_size = jmp_size[i]; 506 int br_offs = blk_starts[i] + jmp_offset[i]; 507 508 // This requires the TRUE branch target be in succs[0] 509 uint bnum = block->non_connector_successor(0)->_pre_order; 510 int offset = blk_starts[bnum] - br_offs; 511 if (bnum > i) { // adjust following block's offset 512 offset -= adjust_block_start; 513 } 514 515 // This block can be a loop header, account for the padding 516 // in the previous block. 517 int block_padding = block_worst_case_pad[i]; 518 assert(i == 0 || block_padding == 0 || br_offs >= block_padding, "Should have at least a padding on top"); 519 // In the following code a nop could be inserted before 520 // the branch which will increase the backward distance. 521 bool needs_padding = ((uint)(br_offs - block_padding) == last_may_be_short_branch_adr); 522 assert(!needs_padding || jmp_offset[i] == 0, "padding only branches at the beginning of block"); 523 524 if (needs_padding && offset <= 0) 525 offset -= nop_size; 526 527 if (_matcher->is_short_branch_offset(mach->rule(), br_size, offset)) { 528 // We've got a winner. Replace this branch. 529 MachNode* replacement = mach->as_MachBranch()->short_branch_version(); 530 531 // Update the jmp_size. 532 int new_size = replacement->size(_regalloc); 533 int diff = br_size - new_size; 534 assert(diff >= (int)nop_size, "short_branch size should be smaller"); 535 // Conservatively take into account padding between 536 // avoid_back_to_back branches. Previous branch could be 537 // converted into avoid_back_to_back branch during next 538 // rounds. 539 if (needs_padding && replacement->avoid_back_to_back(MachNode::AVOID_BEFORE)) { 540 jmp_offset[i] += nop_size; 541 diff -= nop_size; 542 } 543 adjust_block_start += diff; 544 block->map_node(replacement, idx); 545 mach->subsume_by(replacement, C); 546 mach = replacement; 547 progress = true; 548 549 jmp_size[i] = new_size; 550 DEBUG_ONLY( jmp_target[i] = bnum; ); 551 DEBUG_ONLY( jmp_rule[i] = mach->rule(); ); 552 } else { 553 // The jump distance is not short, try again during next iteration. 554 has_short_branch_candidate = true; 555 } 556 } // (mach->may_be_short_branch()) 557 if (mach != NULL && (mach->may_be_short_branch() || 558 mach->avoid_back_to_back(MachNode::AVOID_AFTER))) { 559 last_may_be_short_branch_adr = blk_starts[i] + jmp_offset[i] + jmp_size[i]; 560 } 561 blk_starts[i+1] -= adjust_block_start; 562 } 563 } 564 565 #ifdef ASSERT 566 for (uint i = 0; i < nblocks; i++) { // For all blocks 567 if (jmp_target[i] != 0) { 568 int br_size = jmp_size[i]; 569 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_offset[i]); 570 if (!_matcher->is_short_branch_offset(jmp_rule[i], br_size, offset)) { 571 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]); 572 } 573 assert(_matcher->is_short_branch_offset(jmp_rule[i], br_size, offset), "Displacement too large for short jmp"); 574 } 575 } 576 #endif 577 578 // Step 3, compute the offsets of all blocks, will be done in fill_buffer() 579 // after ScheduleAndBundle(). 580 581 // ------------------ 582 // Compute size for code buffer 583 code_size = blk_starts[nblocks]; 584 585 // Relocation records 586 reloc_size += 1; // Relo entry for exception handler 587 588 // Adjust reloc_size to number of record of relocation info 589 // Min is 2 bytes, max is probably 6 or 8, with a tax up to 25% for 590 // a relocation index. 591 // The CodeBuffer will expand the locs array if this estimate is too low. 592 reloc_size *= 10 / sizeof(relocInfo); 593 } 594 595 //------------------------------FillLocArray----------------------------------- 596 // Create a bit of debug info and append it to the array. The mapping is from 597 // Java local or expression stack to constant, register or stack-slot. For 598 // doubles, insert 2 mappings and return 1 (to tell the caller that the next 599 // entry has been taken care of and caller should skip it). 600 static LocationValue *new_loc_value( PhaseRegAlloc *ra, OptoReg::Name regnum, Location::Type l_type ) { 601 // This should never have accepted Bad before 602 assert(OptoReg::is_valid(regnum), "location must be valid"); 603 return (OptoReg::is_reg(regnum)) 604 ? new LocationValue(Location::new_reg_loc(l_type, OptoReg::as_VMReg(regnum)) ) 605 : new LocationValue(Location::new_stk_loc(l_type, ra->reg2offset(regnum))); 606 } 607 608 609 ObjectValue* 610 Compile::sv_for_node_id(GrowableArray<ScopeValue*> *objs, int id) { 611 for (int i = 0; i < objs->length(); i++) { 612 assert(objs->at(i)->is_object(), "corrupt object cache"); 613 ObjectValue* sv = (ObjectValue*) objs->at(i); 614 if (sv->id() == id) { 615 return sv; 616 } 617 } 618 // Otherwise.. 619 return NULL; 620 } 621 622 void Compile::set_sv_for_object_node(GrowableArray<ScopeValue*> *objs, 623 ObjectValue* sv ) { 624 assert(sv_for_node_id(objs, sv->id()) == NULL, "Precondition"); 625 objs->append(sv); 626 } 627 628 629 void Compile::FillLocArray( int idx, MachSafePointNode* sfpt, Node *local, 630 GrowableArray<ScopeValue*> *array, 631 GrowableArray<ScopeValue*> *objs ) { 632 assert( local, "use _top instead of null" ); 633 if (array->length() != idx) { 634 assert(array->length() == idx + 1, "Unexpected array count"); 635 // Old functionality: 636 // return 637 // New functionality: 638 // Assert if the local is not top. In product mode let the new node 639 // override the old entry. 640 assert(local == top(), "LocArray collision"); 641 if (local == top()) { 642 return; 643 } 644 array->pop(); 645 } 646 const Type *t = local->bottom_type(); 647 648 // Is it a safepoint scalar object node? 649 if (local->is_SafePointScalarObject()) { 650 SafePointScalarObjectNode* spobj = local->as_SafePointScalarObject(); 651 652 ObjectValue* sv = Compile::sv_for_node_id(objs, spobj->_idx); 653 if (sv == NULL) { 654 ciKlass* cik = t->is_oopptr()->klass(); 655 assert(cik->is_instance_klass() || 656 cik->is_array_klass(), "Not supported allocation."); 657 sv = new ObjectValue(spobj->_idx, 658 new ConstantOopWriteValue(cik->java_mirror()->constant_encoding())); 659 Compile::set_sv_for_object_node(objs, sv); 660 661 uint first_ind = spobj->first_index(sfpt->jvms()); 662 for (uint i = 0; i < spobj->n_fields(); i++) { 663 Node* fld_node = sfpt->in(first_ind+i); 664 (void)FillLocArray(sv->field_values()->length(), sfpt, fld_node, sv->field_values(), objs); 665 } 666 } 667 array->append(sv); 668 return; 669 } 670 671 // Grab the register number for the local 672 OptoReg::Name regnum = _regalloc->get_reg_first(local); 673 if( OptoReg::is_valid(regnum) ) {// Got a register/stack? 674 // Record the double as two float registers. 675 // The register mask for such a value always specifies two adjacent 676 // float registers, with the lower register number even. 677 // Normally, the allocation of high and low words to these registers 678 // is irrelevant, because nearly all operations on register pairs 679 // (e.g., StoreD) treat them as a single unit. 680 // Here, we assume in addition that the words in these two registers 681 // stored "naturally" (by operations like StoreD and double stores 682 // within the interpreter) such that the lower-numbered register 683 // is written to the lower memory address. This may seem like 684 // a machine dependency, but it is not--it is a requirement on 685 // the author of the <arch>.ad file to ensure that, for every 686 // even/odd double-register pair to which a double may be allocated, 687 // the word in the even single-register is stored to the first 688 // memory word. (Note that register numbers are completely 689 // arbitrary, and are not tied to any machine-level encodings.) 690 #ifdef _LP64 691 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon ) { 692 array->append(new ConstantIntValue(0)); 693 array->append(new_loc_value( _regalloc, regnum, Location::dbl )); 694 } else if ( t->base() == Type::Long ) { 695 array->append(new ConstantIntValue(0)); 696 array->append(new_loc_value( _regalloc, regnum, Location::lng )); 697 } else if ( t->base() == Type::RawPtr ) { 698 // jsr/ret return address which must be restored into a the full 699 // width 64-bit stack slot. 700 array->append(new_loc_value( _regalloc, regnum, Location::lng )); 701 } 702 #else //_LP64 703 #ifdef SPARC 704 if (t->base() == Type::Long && OptoReg::is_reg(regnum)) { 705 // For SPARC we have to swap high and low words for 706 // long values stored in a single-register (g0-g7). 707 array->append(new_loc_value( _regalloc, regnum , Location::normal )); 708 array->append(new_loc_value( _regalloc, OptoReg::add(regnum,1), Location::normal )); 709 } else 710 #endif //SPARC 711 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon || t->base() == Type::Long ) { 712 // Repack the double/long as two jints. 713 // The convention the interpreter uses is that the second local 714 // holds the first raw word of the native double representation. 715 // This is actually reasonable, since locals and stack arrays 716 // grow downwards in all implementations. 717 // (If, on some machine, the interpreter's Java locals or stack 718 // were to grow upwards, the embedded doubles would be word-swapped.) 719 array->append(new_loc_value( _regalloc, OptoReg::add(regnum,1), Location::normal )); 720 array->append(new_loc_value( _regalloc, regnum , Location::normal )); 721 } 722 #endif //_LP64 723 else if( (t->base() == Type::FloatBot || t->base() == Type::FloatCon) && 724 OptoReg::is_reg(regnum) ) { 725 array->append(new_loc_value( _regalloc, regnum, Matcher::float_in_double() 726 ? Location::float_in_dbl : Location::normal )); 727 } else if( t->base() == Type::Int && OptoReg::is_reg(regnum) ) { 728 array->append(new_loc_value( _regalloc, regnum, Matcher::int_in_long 729 ? Location::int_in_long : Location::normal )); 730 } else if( t->base() == Type::NarrowOop ) { 731 array->append(new_loc_value( _regalloc, regnum, Location::narrowoop )); 732 } else { 733 array->append(new_loc_value( _regalloc, regnum, _regalloc->is_oop(local) ? Location::oop : Location::normal )); 734 } 735 return; 736 } 737 738 // No register. It must be constant data. 739 switch (t->base()) { 740 case Type::Half: // Second half of a double 741 ShouldNotReachHere(); // Caller should skip 2nd halves 742 break; 743 case Type::AnyPtr: 744 array->append(new ConstantOopWriteValue(NULL)); 745 break; 746 case Type::AryPtr: 747 case Type::InstPtr: // fall through 748 array->append(new ConstantOopWriteValue(t->isa_oopptr()->const_oop()->constant_encoding())); 749 break; 750 case Type::NarrowOop: 751 if (t == TypeNarrowOop::NULL_PTR) { 752 array->append(new ConstantOopWriteValue(NULL)); 753 } else { 754 array->append(new ConstantOopWriteValue(t->make_ptr()->isa_oopptr()->const_oop()->constant_encoding())); 755 } 756 break; 757 case Type::Int: 758 array->append(new ConstantIntValue(t->is_int()->get_con())); 759 break; 760 case Type::RawPtr: 761 // A return address (T_ADDRESS). 762 assert((intptr_t)t->is_ptr()->get_con() < (intptr_t)0x10000, "must be a valid BCI"); 763 #ifdef _LP64 764 // Must be restored to the full-width 64-bit stack slot. 765 array->append(new ConstantLongValue(t->is_ptr()->get_con())); 766 #else 767 array->append(new ConstantIntValue(t->is_ptr()->get_con())); 768 #endif 769 break; 770 case Type::FloatCon: { 771 float f = t->is_float_constant()->getf(); 772 array->append(new ConstantIntValue(jint_cast(f))); 773 break; 774 } 775 case Type::DoubleCon: { 776 jdouble d = t->is_double_constant()->getd(); 777 #ifdef _LP64 778 array->append(new ConstantIntValue(0)); 779 array->append(new ConstantDoubleValue(d)); 780 #else 781 // Repack the double as two jints. 782 // The convention the interpreter uses is that the second local 783 // holds the first raw word of the native double representation. 784 // This is actually reasonable, since locals and stack arrays 785 // grow downwards in all implementations. 786 // (If, on some machine, the interpreter's Java locals or stack 787 // were to grow upwards, the embedded doubles would be word-swapped.) 788 jlong_accessor acc; 789 acc.long_value = jlong_cast(d); 790 array->append(new ConstantIntValue(acc.words[1])); 791 array->append(new ConstantIntValue(acc.words[0])); 792 #endif 793 break; 794 } 795 case Type::Long: { 796 jlong d = t->is_long()->get_con(); 797 #ifdef _LP64 798 array->append(new ConstantIntValue(0)); 799 array->append(new ConstantLongValue(d)); 800 #else 801 // Repack the long as two jints. 802 // The convention the interpreter uses is that the second local 803 // holds the first raw word of the native double representation. 804 // This is actually reasonable, since locals and stack arrays 805 // grow downwards in all implementations. 806 // (If, on some machine, the interpreter's Java locals or stack 807 // were to grow upwards, the embedded doubles would be word-swapped.) 808 jlong_accessor acc; 809 acc.long_value = d; 810 array->append(new ConstantIntValue(acc.words[1])); 811 array->append(new ConstantIntValue(acc.words[0])); 812 #endif 813 break; 814 } 815 case Type::Top: // Add an illegal value here 816 array->append(new LocationValue(Location())); 817 break; 818 default: 819 ShouldNotReachHere(); 820 break; 821 } 822 } 823 824 // Determine if this node starts a bundle 825 bool Compile::starts_bundle(const Node *n) const { 826 return (_node_bundling_limit > n->_idx && 827 _node_bundling_base[n->_idx].starts_bundle()); 828 } 829 830 //--------------------------Process_OopMap_Node-------------------------------- 831 void Compile::Process_OopMap_Node(MachNode *mach, int current_offset) { 832 833 // Handle special safepoint nodes for synchronization 834 MachSafePointNode *sfn = mach->as_MachSafePoint(); 835 MachCallNode *mcall; 836 837 #ifdef ENABLE_ZAP_DEAD_LOCALS 838 assert( is_node_getting_a_safepoint(mach), "logic does not match; false negative"); 839 #endif 840 841 int safepoint_pc_offset = current_offset; 842 bool is_method_handle_invoke = false; 843 bool return_oop = false; 844 845 // Add the safepoint in the DebugInfoRecorder 846 if( !mach->is_MachCall() ) { 847 mcall = NULL; 848 debug_info()->add_safepoint(safepoint_pc_offset, sfn->_oop_map); 849 } else { 850 mcall = mach->as_MachCall(); 851 852 // Is the call a MethodHandle call? 853 if (mcall->is_MachCallJava()) { 854 if (mcall->as_MachCallJava()->_method_handle_invoke) { 855 assert(has_method_handle_invokes(), "must have been set during call generation"); 856 is_method_handle_invoke = true; 857 } 858 } 859 860 // Check if a call returns an object. 861 if (mcall->returns_pointer()) { 862 return_oop = true; 863 } 864 safepoint_pc_offset += mcall->ret_addr_offset(); 865 debug_info()->add_safepoint(safepoint_pc_offset, mcall->_oop_map); 866 } 867 868 // Loop over the JVMState list to add scope information 869 // Do not skip safepoints with a NULL method, they need monitor info 870 JVMState* youngest_jvms = sfn->jvms(); 871 int max_depth = youngest_jvms->depth(); 872 873 // Allocate the object pool for scalar-replaced objects -- the map from 874 // small-integer keys (which can be recorded in the local and ostack 875 // arrays) to descriptions of the object state. 876 GrowableArray<ScopeValue*> *objs = new GrowableArray<ScopeValue*>(); 877 878 // Visit scopes from oldest to youngest. 879 for (int depth = 1; depth <= max_depth; depth++) { 880 JVMState* jvms = youngest_jvms->of_depth(depth); 881 int idx; 882 ciMethod* method = jvms->has_method() ? jvms->method() : NULL; 883 // Safepoints that do not have method() set only provide oop-map and monitor info 884 // to support GC; these do not support deoptimization. 885 int num_locs = (method == NULL) ? 0 : jvms->loc_size(); 886 int num_exps = (method == NULL) ? 0 : jvms->stk_size(); 887 int num_mon = jvms->nof_monitors(); 888 assert(method == NULL || jvms->bci() < 0 || num_locs == method->max_locals(), 889 "JVMS local count must match that of the method"); 890 891 // Add Local and Expression Stack Information 892 893 // Insert locals into the locarray 894 GrowableArray<ScopeValue*> *locarray = new GrowableArray<ScopeValue*>(num_locs); 895 for( idx = 0; idx < num_locs; idx++ ) { 896 FillLocArray( idx, sfn, sfn->local(jvms, idx), locarray, objs ); 897 } 898 899 // Insert expression stack entries into the exparray 900 GrowableArray<ScopeValue*> *exparray = new GrowableArray<ScopeValue*>(num_exps); 901 for( idx = 0; idx < num_exps; idx++ ) { 902 FillLocArray( idx, sfn, sfn->stack(jvms, idx), exparray, objs ); 903 } 904 905 // Add in mappings of the monitors 906 assert( !method || 907 !method->is_synchronized() || 908 method->is_native() || 909 num_mon > 0 || 910 !GenerateSynchronizationCode, 911 "monitors must always exist for synchronized methods"); 912 913 // Build the growable array of ScopeValues for exp stack 914 GrowableArray<MonitorValue*> *monarray = new GrowableArray<MonitorValue*>(num_mon); 915 916 // Loop over monitors and insert into array 917 for (idx = 0; idx < num_mon; idx++) { 918 // Grab the node that defines this monitor 919 Node* box_node = sfn->monitor_box(jvms, idx); 920 Node* obj_node = sfn->monitor_obj(jvms, idx); 921 922 // Create ScopeValue for object 923 ScopeValue *scval = NULL; 924 925 if (obj_node->is_SafePointScalarObject()) { 926 SafePointScalarObjectNode* spobj = obj_node->as_SafePointScalarObject(); 927 scval = Compile::sv_for_node_id(objs, spobj->_idx); 928 if (scval == NULL) { 929 const Type *t = spobj->bottom_type(); 930 ciKlass* cik = t->is_oopptr()->klass(); 931 assert(cik->is_instance_klass() || 932 cik->is_array_klass(), "Not supported allocation."); 933 ObjectValue* sv = new ObjectValue(spobj->_idx, 934 new ConstantOopWriteValue(cik->java_mirror()->constant_encoding())); 935 Compile::set_sv_for_object_node(objs, sv); 936 937 uint first_ind = spobj->first_index(youngest_jvms); 938 for (uint i = 0; i < spobj->n_fields(); i++) { 939 Node* fld_node = sfn->in(first_ind+i); 940 (void)FillLocArray(sv->field_values()->length(), sfn, fld_node, sv->field_values(), objs); 941 } 942 scval = sv; 943 } 944 } else if (!obj_node->is_Con()) { 945 OptoReg::Name obj_reg = _regalloc->get_reg_first(obj_node); 946 if( obj_node->bottom_type()->base() == Type::NarrowOop ) { 947 scval = new_loc_value( _regalloc, obj_reg, Location::narrowoop ); 948 } else { 949 scval = new_loc_value( _regalloc, obj_reg, Location::oop ); 950 } 951 } else { 952 const TypePtr *tp = obj_node->get_ptr_type(); 953 scval = new ConstantOopWriteValue(tp->is_oopptr()->const_oop()->constant_encoding()); 954 } 955 956 OptoReg::Name box_reg = BoxLockNode::reg(box_node); 957 Location basic_lock = Location::new_stk_loc(Location::normal,_regalloc->reg2offset(box_reg)); 958 bool eliminated = (box_node->is_BoxLock() && box_node->as_BoxLock()->is_eliminated()); 959 monarray->append(new MonitorValue(scval, basic_lock, eliminated)); 960 } 961 962 // We dump the object pool first, since deoptimization reads it in first. 963 debug_info()->dump_object_pool(objs); 964 965 // Build first class objects to pass to scope 966 DebugToken *locvals = debug_info()->create_scope_values(locarray); 967 DebugToken *expvals = debug_info()->create_scope_values(exparray); 968 DebugToken *monvals = debug_info()->create_monitor_values(monarray); 969 970 // Make method available for all Safepoints 971 ciMethod* scope_method = method ? method : _method; 972 // Describe the scope here 973 assert(jvms->bci() >= InvocationEntryBci && jvms->bci() <= 0x10000, "must be a valid or entry BCI"); 974 assert(!jvms->should_reexecute() || depth == max_depth, "reexecute allowed only for the youngest"); 975 // Now we can describe the scope. 976 debug_info()->describe_scope(safepoint_pc_offset, scope_method, jvms->bci(), jvms->should_reexecute(), is_method_handle_invoke, return_oop, locvals, expvals, monvals); 977 } // End jvms loop 978 979 // Mark the end of the scope set. 980 debug_info()->end_safepoint(safepoint_pc_offset); 981 } 982 983 984 985 // A simplified version of Process_OopMap_Node, to handle non-safepoints. 986 class NonSafepointEmitter { 987 Compile* C; 988 JVMState* _pending_jvms; 989 int _pending_offset; 990 991 void emit_non_safepoint(); 992 993 public: 994 NonSafepointEmitter(Compile* compile) { 995 this->C = compile; 996 _pending_jvms = NULL; 997 _pending_offset = 0; 998 } 999 1000 void observe_instruction(Node* n, int pc_offset) { 1001 if (!C->debug_info()->recording_non_safepoints()) return; 1002 1003 Node_Notes* nn = C->node_notes_at(n->_idx); 1004 if (nn == NULL || nn->jvms() == NULL) return; 1005 if (_pending_jvms != NULL && 1006 _pending_jvms->same_calls_as(nn->jvms())) { 1007 // Repeated JVMS? Stretch it up here. 1008 _pending_offset = pc_offset; 1009 } else { 1010 if (_pending_jvms != NULL && 1011 _pending_offset < pc_offset) { 1012 emit_non_safepoint(); 1013 } 1014 _pending_jvms = NULL; 1015 if (pc_offset > C->debug_info()->last_pc_offset()) { 1016 // This is the only way _pending_jvms can become non-NULL: 1017 _pending_jvms = nn->jvms(); 1018 _pending_offset = pc_offset; 1019 } 1020 } 1021 } 1022 1023 // Stay out of the way of real safepoints: 1024 void observe_safepoint(JVMState* jvms, int pc_offset) { 1025 if (_pending_jvms != NULL && 1026 !_pending_jvms->same_calls_as(jvms) && 1027 _pending_offset < pc_offset) { 1028 emit_non_safepoint(); 1029 } 1030 _pending_jvms = NULL; 1031 } 1032 1033 void flush_at_end() { 1034 if (_pending_jvms != NULL) { 1035 emit_non_safepoint(); 1036 } 1037 _pending_jvms = NULL; 1038 } 1039 }; 1040 1041 void NonSafepointEmitter::emit_non_safepoint() { 1042 JVMState* youngest_jvms = _pending_jvms; 1043 int pc_offset = _pending_offset; 1044 1045 // Clear it now: 1046 _pending_jvms = NULL; 1047 1048 DebugInformationRecorder* debug_info = C->debug_info(); 1049 assert(debug_info->recording_non_safepoints(), "sanity"); 1050 1051 debug_info->add_non_safepoint(pc_offset); 1052 int max_depth = youngest_jvms->depth(); 1053 1054 // Visit scopes from oldest to youngest. 1055 for (int depth = 1; depth <= max_depth; depth++) { 1056 JVMState* jvms = youngest_jvms->of_depth(depth); 1057 ciMethod* method = jvms->has_method() ? jvms->method() : NULL; 1058 assert(!jvms->should_reexecute() || depth==max_depth, "reexecute allowed only for the youngest"); 1059 debug_info->describe_scope(pc_offset, method, jvms->bci(), jvms->should_reexecute()); 1060 } 1061 1062 // Mark the end of the scope set. 1063 debug_info->end_non_safepoint(pc_offset); 1064 } 1065 1066 //------------------------------init_buffer------------------------------------ 1067 CodeBuffer* Compile::init_buffer(uint* blk_starts) { 1068 1069 // Set the initially allocated size 1070 int code_req = initial_code_capacity; 1071 int locs_req = initial_locs_capacity; 1072 int stub_req = TraceJumps ? initial_stub_capacity * 10 : initial_stub_capacity; 1073 int const_req = initial_const_capacity; 1074 1075 int pad_req = NativeCall::instruction_size; 1076 // The extra spacing after the code is necessary on some platforms. 1077 // Sometimes we need to patch in a jump after the last instruction, 1078 // if the nmethod has been deoptimized. (See 4932387, 4894843.) 1079 1080 // Compute the byte offset where we can store the deopt pc. 1081 if (fixed_slots() != 0) { 1082 _orig_pc_slot_offset_in_bytes = _regalloc->reg2offset(OptoReg::stack2reg(_orig_pc_slot)); 1083 } 1084 1085 // Compute prolog code size 1086 _method_size = 0; 1087 _frame_slots = OptoReg::reg2stack(_matcher->_old_SP)+_regalloc->_framesize; 1088 #if defined(IA64) && !defined(AIX) 1089 if (save_argument_registers()) { 1090 // 4815101: this is a stub with implicit and unknown precision fp args. 1091 // The usual spill mechanism can only generate stfd's in this case, which 1092 // doesn't work if the fp reg to spill contains a single-precision denorm. 1093 // Instead, we hack around the normal spill mechanism using stfspill's and 1094 // ldffill's in the MachProlog and MachEpilog emit methods. We allocate 1095 // space here for the fp arg regs (f8-f15) we're going to thusly spill. 1096 // 1097 // If we ever implement 16-byte 'registers' == stack slots, we can 1098 // get rid of this hack and have SpillCopy generate stfspill/ldffill 1099 // instead of stfd/stfs/ldfd/ldfs. 1100 _frame_slots += 8*(16/BytesPerInt); 1101 } 1102 #endif 1103 assert(_frame_slots >= 0 && _frame_slots < 1000000, "sanity check"); 1104 1105 if (has_mach_constant_base_node()) { 1106 uint add_size = 0; 1107 // Fill the constant table. 1108 // Note: This must happen before shorten_branches. 1109 for (uint i = 0; i < _cfg->number_of_blocks(); i++) { 1110 Block* b = _cfg->get_block(i); 1111 1112 for (uint j = 0; j < b->number_of_nodes(); j++) { 1113 Node* n = b->get_node(j); 1114 1115 // If the node is a MachConstantNode evaluate the constant 1116 // value section. 1117 if (n->is_MachConstant()) { 1118 MachConstantNode* machcon = n->as_MachConstant(); 1119 machcon->eval_constant(C); 1120 } else if (n->is_Mach()) { 1121 // On Power there are more nodes that issue constants. 1122 add_size += (n->as_Mach()->ins_num_consts() * 8); 1123 } 1124 } 1125 } 1126 1127 // Calculate the offsets of the constants and the size of the 1128 // constant table (including the padding to the next section). 1129 constant_table().calculate_offsets_and_size(); 1130 const_req = constant_table().size() + add_size; 1131 } 1132 1133 // Initialize the space for the BufferBlob used to find and verify 1134 // instruction size in MachNode::emit_size() 1135 init_scratch_buffer_blob(const_req); 1136 if (failing()) return NULL; // Out of memory 1137 1138 // Pre-compute the length of blocks and replace 1139 // long branches with short if machine supports it. 1140 shorten_branches(blk_starts, code_req, locs_req, stub_req); 1141 1142 // nmethod and CodeBuffer count stubs & constants as part of method's code. 1143 // class HandlerImpl is platform-specific and defined in the *.ad files. 1144 int exception_handler_req = HandlerImpl::size_exception_handler() + MAX_stubs_size; // add marginal slop for handler 1145 int deopt_handler_req = HandlerImpl::size_deopt_handler() + MAX_stubs_size; // add marginal slop for handler 1146 stub_req += MAX_stubs_size; // ensure per-stub margin 1147 code_req += MAX_inst_size; // ensure per-instruction margin 1148 1149 if (StressCodeBuffers) 1150 code_req = const_req = stub_req = exception_handler_req = deopt_handler_req = 0x10; // force expansion 1151 1152 int total_req = 1153 const_req + 1154 code_req + 1155 pad_req + 1156 stub_req + 1157 exception_handler_req + 1158 deopt_handler_req; // deopt handler 1159 1160 if (has_method_handle_invokes()) 1161 total_req += deopt_handler_req; // deopt MH handler 1162 1163 CodeBuffer* cb = code_buffer(); 1164 cb->initialize(total_req, locs_req); 1165 1166 // Have we run out of code space? 1167 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { 1168 C->record_failure("CodeCache is full"); 1169 return NULL; 1170 } 1171 // Configure the code buffer. 1172 cb->initialize_consts_size(const_req); 1173 cb->initialize_stubs_size(stub_req); 1174 cb->initialize_oop_recorder(env()->oop_recorder()); 1175 1176 // fill in the nop array for bundling computations 1177 MachNode *_nop_list[Bundle::_nop_count]; 1178 Bundle::initialize_nops(_nop_list); 1179 1180 return cb; 1181 } 1182 1183 //------------------------------fill_buffer------------------------------------ 1184 void Compile::fill_buffer(CodeBuffer* cb, uint* blk_starts) { 1185 // blk_starts[] contains offsets calculated during short branches processing, 1186 // offsets should not be increased during following steps. 1187 1188 // Compute the size of first NumberOfLoopInstrToAlign instructions at head 1189 // of a loop. It is used to determine the padding for loop alignment. 1190 compute_loop_first_inst_sizes(); 1191 1192 // Create oopmap set. 1193 _oop_map_set = new OopMapSet(); 1194 1195 // !!!!! This preserves old handling of oopmaps for now 1196 debug_info()->set_oopmaps(_oop_map_set); 1197 1198 uint nblocks = _cfg->number_of_blocks(); 1199 // Count and start of implicit null check instructions 1200 uint inct_cnt = 0; 1201 uint *inct_starts = NEW_RESOURCE_ARRAY(uint, nblocks+1); 1202 1203 // Count and start of calls 1204 uint *call_returns = NEW_RESOURCE_ARRAY(uint, nblocks+1); 1205 1206 uint return_offset = 0; 1207 int nop_size = (new MachNopNode())->size(_regalloc); 1208 1209 int previous_offset = 0; 1210 int current_offset = 0; 1211 int last_call_offset = -1; 1212 int last_avoid_back_to_back_offset = -1; 1213 #ifdef ASSERT 1214 uint* jmp_target = NEW_RESOURCE_ARRAY(uint,nblocks); 1215 uint* jmp_offset = NEW_RESOURCE_ARRAY(uint,nblocks); 1216 uint* jmp_size = NEW_RESOURCE_ARRAY(uint,nblocks); 1217 uint* jmp_rule = NEW_RESOURCE_ARRAY(uint,nblocks); 1218 #endif 1219 1220 // Create an array of unused labels, one for each basic block, if printing is enabled 1221 #ifndef PRODUCT 1222 int *node_offsets = NULL; 1223 uint node_offset_limit = unique(); 1224 1225 if (print_assembly()) 1226 node_offsets = NEW_RESOURCE_ARRAY(int, node_offset_limit); 1227 #endif 1228 1229 NonSafepointEmitter non_safepoints(this); // emit non-safepoints lazily 1230 1231 // Emit the constant table. 1232 if (has_mach_constant_base_node()) { 1233 constant_table().emit(*cb); 1234 } 1235 1236 // Create an array of labels, one for each basic block 1237 Label *blk_labels = NEW_RESOURCE_ARRAY(Label, nblocks+1); 1238 for (uint i=0; i <= nblocks; i++) { 1239 blk_labels[i].init(); 1240 } 1241 1242 // ------------------ 1243 // Now fill in the code buffer 1244 Node *delay_slot = NULL; 1245 1246 for (uint i = 0; i < nblocks; i++) { 1247 Block* block = _cfg->get_block(i); 1248 Node* head = block->head(); 1249 1250 // If this block needs to start aligned (i.e, can be reached other 1251 // than by falling-thru from the previous block), then force the 1252 // start of a new bundle. 1253 if (Pipeline::requires_bundling() && starts_bundle(head)) { 1254 cb->flush_bundle(true); 1255 } 1256 1257 #ifdef ASSERT 1258 if (!block->is_connector()) { 1259 stringStream st; 1260 block->dump_head(_cfg, &st); 1261 MacroAssembler(cb).block_comment(st.as_string()); 1262 } 1263 jmp_target[i] = 0; 1264 jmp_offset[i] = 0; 1265 jmp_size[i] = 0; 1266 jmp_rule[i] = 0; 1267 #endif 1268 int blk_offset = current_offset; 1269 1270 // Define the label at the beginning of the basic block 1271 MacroAssembler(cb).bind(blk_labels[block->_pre_order]); 1272 1273 uint last_inst = block->number_of_nodes(); 1274 1275 // Emit block normally, except for last instruction. 1276 // Emit means "dump code bits into code buffer". 1277 for (uint j = 0; j<last_inst; j++) { 1278 1279 // Get the node 1280 Node* n = block->get_node(j); 1281 1282 // See if delay slots are supported 1283 if (valid_bundle_info(n) && 1284 node_bundling(n)->used_in_unconditional_delay()) { 1285 assert(delay_slot == NULL, "no use of delay slot node"); 1286 assert(n->size(_regalloc) == Pipeline::instr_unit_size(), "delay slot instruction wrong size"); 1287 1288 delay_slot = n; 1289 continue; 1290 } 1291 1292 // If this starts a new instruction group, then flush the current one 1293 // (but allow split bundles) 1294 if (Pipeline::requires_bundling() && starts_bundle(n)) 1295 cb->flush_bundle(false); 1296 1297 // The following logic is duplicated in the code ifdeffed for 1298 // ENABLE_ZAP_DEAD_LOCALS which appears above in this file. It 1299 // should be factored out. Or maybe dispersed to the nodes? 1300 1301 // Special handling for SafePoint/Call Nodes 1302 bool is_mcall = false; 1303 if (n->is_Mach()) { 1304 MachNode *mach = n->as_Mach(); 1305 is_mcall = n->is_MachCall(); 1306 bool is_sfn = n->is_MachSafePoint(); 1307 1308 // If this requires all previous instructions be flushed, then do so 1309 if (is_sfn || is_mcall || mach->alignment_required() != 1) { 1310 cb->flush_bundle(true); 1311 current_offset = cb->insts_size(); 1312 } 1313 1314 // A padding may be needed again since a previous instruction 1315 // could be moved to delay slot. 1316 1317 // align the instruction if necessary 1318 int padding = mach->compute_padding(current_offset); 1319 // Make sure safepoint node for polling is distinct from a call's 1320 // return by adding a nop if needed. 1321 if (is_sfn && !is_mcall && padding == 0 && current_offset == last_call_offset) { 1322 padding = nop_size; 1323 } 1324 if (padding == 0 && mach->avoid_back_to_back(MachNode::AVOID_BEFORE) && 1325 current_offset == last_avoid_back_to_back_offset) { 1326 // Avoid back to back some instructions. 1327 padding = nop_size; 1328 } 1329 1330 if(padding > 0) { 1331 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size"); 1332 int nops_cnt = padding / nop_size; 1333 MachNode *nop = new MachNopNode(nops_cnt); 1334 block->insert_node(nop, j++); 1335 last_inst++; 1336 _cfg->map_node_to_block(nop, block); 1337 nop->emit(*cb, _regalloc); 1338 cb->flush_bundle(true); 1339 current_offset = cb->insts_size(); 1340 } 1341 1342 // Remember the start of the last call in a basic block 1343 if (is_mcall) { 1344 MachCallNode *mcall = mach->as_MachCall(); 1345 1346 // This destination address is NOT PC-relative 1347 mcall->method_set((intptr_t)mcall->entry_point()); 1348 1349 // Save the return address 1350 call_returns[block->_pre_order] = current_offset + mcall->ret_addr_offset(); 1351 1352 if (mcall->is_MachCallLeaf()) { 1353 is_mcall = false; 1354 is_sfn = false; 1355 } 1356 } 1357 1358 // sfn will be valid whenever mcall is valid now because of inheritance 1359 if (is_sfn || is_mcall) { 1360 1361 // Handle special safepoint nodes for synchronization 1362 if (!is_mcall) { 1363 MachSafePointNode *sfn = mach->as_MachSafePoint(); 1364 // !!!!! Stubs only need an oopmap right now, so bail out 1365 if (sfn->jvms()->method() == NULL) { 1366 // Write the oopmap directly to the code blob??!! 1367 # ifdef ENABLE_ZAP_DEAD_LOCALS 1368 assert( !is_node_getting_a_safepoint(sfn), "logic does not match; false positive"); 1369 # endif 1370 continue; 1371 } 1372 } // End synchronization 1373 1374 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(), 1375 current_offset); 1376 Process_OopMap_Node(mach, current_offset); 1377 } // End if safepoint 1378 1379 // If this is a null check, then add the start of the previous instruction to the list 1380 else if( mach->is_MachNullCheck() ) { 1381 inct_starts[inct_cnt++] = previous_offset; 1382 } 1383 1384 // If this is a branch, then fill in the label with the target BB's label 1385 else if (mach->is_MachBranch()) { 1386 // This requires the TRUE branch target be in succs[0] 1387 uint block_num = block->non_connector_successor(0)->_pre_order; 1388 1389 // Try to replace long branch if delay slot is not used, 1390 // it is mostly for back branches since forward branch's 1391 // distance is not updated yet. 1392 bool delay_slot_is_used = valid_bundle_info(n) && 1393 node_bundling(n)->use_unconditional_delay(); 1394 if (!delay_slot_is_used && mach->may_be_short_branch()) { 1395 assert(delay_slot == NULL, "not expecting delay slot node"); 1396 int br_size = n->size(_regalloc); 1397 int offset = blk_starts[block_num] - current_offset; 1398 if (block_num >= i) { 1399 // Current and following block's offset are not 1400 // finalized yet, adjust distance by the difference 1401 // between calculated and final offsets of current block. 1402 offset -= (blk_starts[i] - blk_offset); 1403 } 1404 // In the following code a nop could be inserted before 1405 // the branch which will increase the backward distance. 1406 bool needs_padding = (current_offset == last_avoid_back_to_back_offset); 1407 if (needs_padding && offset <= 0) 1408 offset -= nop_size; 1409 1410 if (_matcher->is_short_branch_offset(mach->rule(), br_size, offset)) { 1411 // We've got a winner. Replace this branch. 1412 MachNode* replacement = mach->as_MachBranch()->short_branch_version(); 1413 1414 // Update the jmp_size. 1415 int new_size = replacement->size(_regalloc); 1416 assert((br_size - new_size) >= (int)nop_size, "short_branch size should be smaller"); 1417 // Insert padding between avoid_back_to_back branches. 1418 if (needs_padding && replacement->avoid_back_to_back(MachNode::AVOID_BEFORE)) { 1419 MachNode *nop = new MachNopNode(); 1420 block->insert_node(nop, j++); 1421 _cfg->map_node_to_block(nop, block); 1422 last_inst++; 1423 nop->emit(*cb, _regalloc); 1424 cb->flush_bundle(true); 1425 current_offset = cb->insts_size(); 1426 } 1427 #ifdef ASSERT 1428 jmp_target[i] = block_num; 1429 jmp_offset[i] = current_offset - blk_offset; 1430 jmp_size[i] = new_size; 1431 jmp_rule[i] = mach->rule(); 1432 #endif 1433 block->map_node(replacement, j); 1434 mach->subsume_by(replacement, C); 1435 n = replacement; 1436 mach = replacement; 1437 } 1438 } 1439 mach->as_MachBranch()->label_set( &blk_labels[block_num], block_num ); 1440 } else if (mach->ideal_Opcode() == Op_Jump) { 1441 for (uint h = 0; h < block->_num_succs; h++) { 1442 Block* succs_block = block->_succs[h]; 1443 for (uint j = 1; j < succs_block->num_preds(); j++) { 1444 Node* jpn = succs_block->pred(j); 1445 if (jpn->is_JumpProj() && jpn->in(0) == mach) { 1446 uint block_num = succs_block->non_connector()->_pre_order; 1447 Label *blkLabel = &blk_labels[block_num]; 1448 mach->add_case_label(jpn->as_JumpProj()->proj_no(), blkLabel); 1449 } 1450 } 1451 } 1452 } 1453 #ifdef ASSERT 1454 // Check that oop-store precedes the card-mark 1455 else if (mach->ideal_Opcode() == Op_StoreCM) { 1456 uint storeCM_idx = j; 1457 int count = 0; 1458 for (uint prec = mach->req(); prec < mach->len(); prec++) { 1459 Node *oop_store = mach->in(prec); // Precedence edge 1460 if (oop_store == NULL) continue; 1461 count++; 1462 uint i4; 1463 for (i4 = 0; i4 < last_inst; ++i4) { 1464 if (block->get_node(i4) == oop_store) { 1465 break; 1466 } 1467 } 1468 // Note: This test can provide a false failure if other precedence 1469 // edges have been added to the storeCMNode. 1470 assert(i4 == last_inst || i4 < storeCM_idx, "CM card-mark executes before oop-store"); 1471 } 1472 assert(count > 0, "storeCM expects at least one precedence edge"); 1473 } 1474 #endif 1475 else if (!n->is_Proj()) { 1476 // Remember the beginning of the previous instruction, in case 1477 // it's followed by a flag-kill and a null-check. Happens on 1478 // Intel all the time, with add-to-memory kind of opcodes. 1479 previous_offset = current_offset; 1480 } 1481 1482 // Not an else-if! 1483 // If this is a trap based cmp then add its offset to the list. 1484 if (mach->is_TrapBasedCheckNode()) { 1485 inct_starts[inct_cnt++] = current_offset; 1486 } 1487 } 1488 1489 // Verify that there is sufficient space remaining 1490 cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size); 1491 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { 1492 C->record_failure("CodeCache is full"); 1493 return; 1494 } 1495 1496 // Save the offset for the listing 1497 #ifndef PRODUCT 1498 if (node_offsets && n->_idx < node_offset_limit) 1499 node_offsets[n->_idx] = cb->insts_size(); 1500 #endif 1501 1502 // "Normal" instruction case 1503 DEBUG_ONLY( uint instr_offset = cb->insts_size(); ) 1504 n->emit(*cb, _regalloc); 1505 current_offset = cb->insts_size(); 1506 1507 // Above we only verified that there is enough space in the instruction section. 1508 // However, the instruction may emit stubs that cause code buffer expansion. 1509 // Bail out here if expansion failed due to a lack of code cache space. 1510 if (failing()) { 1511 return; 1512 } 1513 1514 #ifdef ASSERT 1515 if (n->size(_regalloc) < (current_offset-instr_offset)) { 1516 n->dump(); 1517 assert(false, "wrong size of mach node"); 1518 } 1519 #endif 1520 non_safepoints.observe_instruction(n, current_offset); 1521 1522 // mcall is last "call" that can be a safepoint 1523 // record it so we can see if a poll will directly follow it 1524 // in which case we'll need a pad to make the PcDesc sites unique 1525 // see 5010568. This can be slightly inaccurate but conservative 1526 // in the case that return address is not actually at current_offset. 1527 // This is a small price to pay. 1528 1529 if (is_mcall) { 1530 last_call_offset = current_offset; 1531 } 1532 1533 if (n->is_Mach() && n->as_Mach()->avoid_back_to_back(MachNode::AVOID_AFTER)) { 1534 // Avoid back to back some instructions. 1535 last_avoid_back_to_back_offset = current_offset; 1536 } 1537 1538 // See if this instruction has a delay slot 1539 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) { 1540 assert(delay_slot != NULL, "expecting delay slot node"); 1541 1542 // Back up 1 instruction 1543 cb->set_insts_end(cb->insts_end() - Pipeline::instr_unit_size()); 1544 1545 // Save the offset for the listing 1546 #ifndef PRODUCT 1547 if (node_offsets && delay_slot->_idx < node_offset_limit) 1548 node_offsets[delay_slot->_idx] = cb->insts_size(); 1549 #endif 1550 1551 // Support a SafePoint in the delay slot 1552 if (delay_slot->is_MachSafePoint()) { 1553 MachNode *mach = delay_slot->as_Mach(); 1554 // !!!!! Stubs only need an oopmap right now, so bail out 1555 if (!mach->is_MachCall() && mach->as_MachSafePoint()->jvms()->method() == NULL) { 1556 // Write the oopmap directly to the code blob??!! 1557 # ifdef ENABLE_ZAP_DEAD_LOCALS 1558 assert( !is_node_getting_a_safepoint(mach), "logic does not match; false positive"); 1559 # endif 1560 delay_slot = NULL; 1561 continue; 1562 } 1563 1564 int adjusted_offset = current_offset - Pipeline::instr_unit_size(); 1565 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(), 1566 adjusted_offset); 1567 // Generate an OopMap entry 1568 Process_OopMap_Node(mach, adjusted_offset); 1569 } 1570 1571 // Insert the delay slot instruction 1572 delay_slot->emit(*cb, _regalloc); 1573 1574 // Don't reuse it 1575 delay_slot = NULL; 1576 } 1577 1578 } // End for all instructions in block 1579 1580 // If the next block is the top of a loop, pad this block out to align 1581 // the loop top a little. Helps prevent pipe stalls at loop back branches. 1582 if (i < nblocks-1) { 1583 Block *nb = _cfg->get_block(i + 1); 1584 int padding = nb->alignment_padding(current_offset); 1585 if( padding > 0 ) { 1586 MachNode *nop = new MachNopNode(padding / nop_size); 1587 block->insert_node(nop, block->number_of_nodes()); 1588 _cfg->map_node_to_block(nop, block); 1589 nop->emit(*cb, _regalloc); 1590 current_offset = cb->insts_size(); 1591 } 1592 } 1593 // Verify that the distance for generated before forward 1594 // short branches is still valid. 1595 guarantee((int)(blk_starts[i+1] - blk_starts[i]) >= (current_offset - blk_offset), "shouldn't increase block size"); 1596 1597 // Save new block start offset 1598 blk_starts[i] = blk_offset; 1599 } // End of for all blocks 1600 blk_starts[nblocks] = current_offset; 1601 1602 non_safepoints.flush_at_end(); 1603 1604 // Offset too large? 1605 if (failing()) return; 1606 1607 // Define a pseudo-label at the end of the code 1608 MacroAssembler(cb).bind( blk_labels[nblocks] ); 1609 1610 // Compute the size of the first block 1611 _first_block_size = blk_labels[1].loc_pos() - blk_labels[0].loc_pos(); 1612 1613 assert(cb->insts_size() < 500000, "method is unreasonably large"); 1614 1615 #ifdef ASSERT 1616 for (uint i = 0; i < nblocks; i++) { // For all blocks 1617 if (jmp_target[i] != 0) { 1618 int br_size = jmp_size[i]; 1619 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_offset[i]); 1620 if (!_matcher->is_short_branch_offset(jmp_rule[i], br_size, offset)) { 1621 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]); 1622 assert(false, "Displacement too large for short jmp"); 1623 } 1624 } 1625 } 1626 #endif 1627 1628 #ifndef PRODUCT 1629 // Information on the size of the method, without the extraneous code 1630 Scheduling::increment_method_size(cb->insts_size()); 1631 #endif 1632 1633 // ------------------ 1634 // Fill in exception table entries. 1635 FillExceptionTables(inct_cnt, call_returns, inct_starts, blk_labels); 1636 1637 // Only java methods have exception handlers and deopt handlers 1638 // class HandlerImpl is platform-specific and defined in the *.ad files. 1639 if (_method) { 1640 // Emit the exception handler code. 1641 _code_offsets.set_value(CodeOffsets::Exceptions, HandlerImpl::emit_exception_handler(*cb)); 1642 if (failing()) { 1643 return; // CodeBuffer::expand failed 1644 } 1645 // Emit the deopt handler code. 1646 _code_offsets.set_value(CodeOffsets::Deopt, HandlerImpl::emit_deopt_handler(*cb)); 1647 1648 // Emit the MethodHandle deopt handler code (if required). 1649 if (has_method_handle_invokes() && !failing()) { 1650 // We can use the same code as for the normal deopt handler, we 1651 // just need a different entry point address. 1652 _code_offsets.set_value(CodeOffsets::DeoptMH, HandlerImpl::emit_deopt_handler(*cb)); 1653 } 1654 } 1655 1656 // One last check for failed CodeBuffer::expand: 1657 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { 1658 C->record_failure("CodeCache is full"); 1659 return; 1660 } 1661 1662 #ifndef PRODUCT 1663 // Dump the assembly code, including basic-block numbers 1664 if (print_assembly()) { 1665 ttyLocker ttyl; // keep the following output all in one block 1666 if (!VMThread::should_terminate()) { // test this under the tty lock 1667 // This output goes directly to the tty, not the compiler log. 1668 // To enable tools to match it up with the compilation activity, 1669 // be sure to tag this tty output with the compile ID. 1670 if (xtty != NULL) { 1671 xtty->head("opto_assembly compile_id='%d'%s", compile_id(), 1672 is_osr_compilation() ? " compile_kind='osr'" : 1673 ""); 1674 } 1675 if (method() != NULL) { 1676 method()->print_metadata(); 1677 } 1678 dump_asm(node_offsets, node_offset_limit); 1679 if (xtty != NULL) { 1680 xtty->tail("opto_assembly"); 1681 } 1682 } 1683 } 1684 #endif 1685 1686 } 1687 1688 void Compile::FillExceptionTables(uint cnt, uint *call_returns, uint *inct_starts, Label *blk_labels) { 1689 _inc_table.set_size(cnt); 1690 1691 uint inct_cnt = 0; 1692 for (uint i = 0; i < _cfg->number_of_blocks(); i++) { 1693 Block* block = _cfg->get_block(i); 1694 Node *n = NULL; 1695 int j; 1696 1697 // Find the branch; ignore trailing NOPs. 1698 for (j = block->number_of_nodes() - 1; j >= 0; j--) { 1699 n = block->get_node(j); 1700 if (!n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con) { 1701 break; 1702 } 1703 } 1704 1705 // If we didn't find anything, continue 1706 if (j < 0) { 1707 continue; 1708 } 1709 1710 // Compute ExceptionHandlerTable subtable entry and add it 1711 // (skip empty blocks) 1712 if (n->is_Catch()) { 1713 1714 // Get the offset of the return from the call 1715 uint call_return = call_returns[block->_pre_order]; 1716 #ifdef ASSERT 1717 assert( call_return > 0, "no call seen for this basic block" ); 1718 while (block->get_node(--j)->is_MachProj()) ; 1719 assert(block->get_node(j)->is_MachCall(), "CatchProj must follow call"); 1720 #endif 1721 // last instruction is a CatchNode, find it's CatchProjNodes 1722 int nof_succs = block->_num_succs; 1723 // allocate space 1724 GrowableArray<intptr_t> handler_bcis(nof_succs); 1725 GrowableArray<intptr_t> handler_pcos(nof_succs); 1726 // iterate through all successors 1727 for (int j = 0; j < nof_succs; j++) { 1728 Block* s = block->_succs[j]; 1729 bool found_p = false; 1730 for (uint k = 1; k < s->num_preds(); k++) { 1731 Node* pk = s->pred(k); 1732 if (pk->is_CatchProj() && pk->in(0) == n) { 1733 const CatchProjNode* p = pk->as_CatchProj(); 1734 found_p = true; 1735 // add the corresponding handler bci & pco information 1736 if (p->_con != CatchProjNode::fall_through_index) { 1737 // p leads to an exception handler (and is not fall through) 1738 assert(s == _cfg->get_block(s->_pre_order), "bad numbering"); 1739 // no duplicates, please 1740 if (!handler_bcis.contains(p->handler_bci())) { 1741 uint block_num = s->non_connector()->_pre_order; 1742 handler_bcis.append(p->handler_bci()); 1743 handler_pcos.append(blk_labels[block_num].loc_pos()); 1744 } 1745 } 1746 } 1747 } 1748 assert(found_p, "no matching predecessor found"); 1749 // Note: Due to empty block removal, one block may have 1750 // several CatchProj inputs, from the same Catch. 1751 } 1752 1753 // Set the offset of the return from the call 1754 _handler_table.add_subtable(call_return, &handler_bcis, NULL, &handler_pcos); 1755 continue; 1756 } 1757 1758 // Handle implicit null exception table updates 1759 if (n->is_MachNullCheck()) { 1760 uint block_num = block->non_connector_successor(0)->_pre_order; 1761 _inc_table.append(inct_starts[inct_cnt++], blk_labels[block_num].loc_pos()); 1762 continue; 1763 } 1764 // Handle implicit exception table updates: trap instructions. 1765 if (n->is_Mach() && n->as_Mach()->is_TrapBasedCheckNode()) { 1766 uint block_num = block->non_connector_successor(0)->_pre_order; 1767 _inc_table.append(inct_starts[inct_cnt++], blk_labels[block_num].loc_pos()); 1768 continue; 1769 } 1770 } // End of for all blocks fill in exception table entries 1771 } 1772 1773 // Static Variables 1774 #ifndef PRODUCT 1775 uint Scheduling::_total_nop_size = 0; 1776 uint Scheduling::_total_method_size = 0; 1777 uint Scheduling::_total_branches = 0; 1778 uint Scheduling::_total_unconditional_delays = 0; 1779 uint Scheduling::_total_instructions_per_bundle[Pipeline::_max_instrs_per_cycle+1]; 1780 #endif 1781 1782 // Initializer for class Scheduling 1783 1784 Scheduling::Scheduling(Arena *arena, Compile &compile) 1785 : _arena(arena), 1786 _cfg(compile.cfg()), 1787 _regalloc(compile.regalloc()), 1788 _reg_node(arena), 1789 _bundle_instr_count(0), 1790 _bundle_cycle_number(0), 1791 _scheduled(arena), 1792 _available(arena), 1793 _next_node(NULL), 1794 _bundle_use(0, 0, resource_count, &_bundle_use_elements[0]), 1795 _pinch_free_list(arena) 1796 #ifndef PRODUCT 1797 , _branches(0) 1798 , _unconditional_delays(0) 1799 #endif 1800 { 1801 // Create a MachNopNode 1802 _nop = new MachNopNode(); 1803 1804 // Now that the nops are in the array, save the count 1805 // (but allow entries for the nops) 1806 _node_bundling_limit = compile.unique(); 1807 uint node_max = _regalloc->node_regs_max_index(); 1808 1809 compile.set_node_bundling_limit(_node_bundling_limit); 1810 1811 // This one is persistent within the Compile class 1812 _node_bundling_base = NEW_ARENA_ARRAY(compile.comp_arena(), Bundle, node_max); 1813 1814 // Allocate space for fixed-size arrays 1815 _node_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max); 1816 _uses = NEW_ARENA_ARRAY(arena, short, node_max); 1817 _current_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max); 1818 1819 // Clear the arrays 1820 memset(_node_bundling_base, 0, node_max * sizeof(Bundle)); 1821 memset(_node_latency, 0, node_max * sizeof(unsigned short)); 1822 memset(_uses, 0, node_max * sizeof(short)); 1823 memset(_current_latency, 0, node_max * sizeof(unsigned short)); 1824 1825 // Clear the bundling information 1826 memcpy(_bundle_use_elements, Pipeline_Use::elaborated_elements, sizeof(Pipeline_Use::elaborated_elements)); 1827 1828 // Get the last node 1829 Block* block = _cfg->get_block(_cfg->number_of_blocks() - 1); 1830 1831 _next_node = block->get_node(block->number_of_nodes() - 1); 1832 } 1833 1834 #ifndef PRODUCT 1835 // Scheduling destructor 1836 Scheduling::~Scheduling() { 1837 _total_branches += _branches; 1838 _total_unconditional_delays += _unconditional_delays; 1839 } 1840 #endif 1841 1842 // Step ahead "i" cycles 1843 void Scheduling::step(uint i) { 1844 1845 Bundle *bundle = node_bundling(_next_node); 1846 bundle->set_starts_bundle(); 1847 1848 // Update the bundle record, but leave the flags information alone 1849 if (_bundle_instr_count > 0) { 1850 bundle->set_instr_count(_bundle_instr_count); 1851 bundle->set_resources_used(_bundle_use.resourcesUsed()); 1852 } 1853 1854 // Update the state information 1855 _bundle_instr_count = 0; 1856 _bundle_cycle_number += i; 1857 _bundle_use.step(i); 1858 } 1859 1860 void Scheduling::step_and_clear() { 1861 Bundle *bundle = node_bundling(_next_node); 1862 bundle->set_starts_bundle(); 1863 1864 // Update the bundle record 1865 if (_bundle_instr_count > 0) { 1866 bundle->set_instr_count(_bundle_instr_count); 1867 bundle->set_resources_used(_bundle_use.resourcesUsed()); 1868 1869 _bundle_cycle_number += 1; 1870 } 1871 1872 // Clear the bundling information 1873 _bundle_instr_count = 0; 1874 _bundle_use.reset(); 1875 1876 memcpy(_bundle_use_elements, 1877 Pipeline_Use::elaborated_elements, 1878 sizeof(Pipeline_Use::elaborated_elements)); 1879 } 1880 1881 // Perform instruction scheduling and bundling over the sequence of 1882 // instructions in backwards order. 1883 void Compile::ScheduleAndBundle() { 1884 1885 // Don't optimize this if it isn't a method 1886 if (!_method) 1887 return; 1888 1889 // Don't optimize this if scheduling is disabled 1890 if (!do_scheduling()) 1891 return; 1892 1893 // Scheduling code works only with pairs (16 bytes) maximum. 1894 if (max_vector_size() > 16) 1895 return; 1896 1897 TracePhase tp("isched", &timers[_t_instrSched]); 1898 1899 // Create a data structure for all the scheduling information 1900 Scheduling scheduling(Thread::current()->resource_area(), *this); 1901 1902 // Walk backwards over each basic block, computing the needed alignment 1903 // Walk over all the basic blocks 1904 scheduling.DoScheduling(); 1905 } 1906 1907 // Compute the latency of all the instructions. This is fairly simple, 1908 // because we already have a legal ordering. Walk over the instructions 1909 // from first to last, and compute the latency of the instruction based 1910 // on the latency of the preceding instruction(s). 1911 void Scheduling::ComputeLocalLatenciesForward(const Block *bb) { 1912 #ifndef PRODUCT 1913 if (_cfg->C->trace_opto_output()) 1914 tty->print("# -> ComputeLocalLatenciesForward\n"); 1915 #endif 1916 1917 // Walk over all the schedulable instructions 1918 for( uint j=_bb_start; j < _bb_end; j++ ) { 1919 1920 // This is a kludge, forcing all latency calculations to start at 1. 1921 // Used to allow latency 0 to force an instruction to the beginning 1922 // of the bb 1923 uint latency = 1; 1924 Node *use = bb->get_node(j); 1925 uint nlen = use->len(); 1926 1927 // Walk over all the inputs 1928 for ( uint k=0; k < nlen; k++ ) { 1929 Node *def = use->in(k); 1930 if (!def) 1931 continue; 1932 1933 uint l = _node_latency[def->_idx] + use->latency(k); 1934 if (latency < l) 1935 latency = l; 1936 } 1937 1938 _node_latency[use->_idx] = latency; 1939 1940 #ifndef PRODUCT 1941 if (_cfg->C->trace_opto_output()) { 1942 tty->print("# latency %4d: ", latency); 1943 use->dump(); 1944 } 1945 #endif 1946 } 1947 1948 #ifndef PRODUCT 1949 if (_cfg->C->trace_opto_output()) 1950 tty->print("# <- ComputeLocalLatenciesForward\n"); 1951 #endif 1952 1953 } // end ComputeLocalLatenciesForward 1954 1955 // See if this node fits into the present instruction bundle 1956 bool Scheduling::NodeFitsInBundle(Node *n) { 1957 uint n_idx = n->_idx; 1958 1959 // If this is the unconditional delay instruction, then it fits 1960 if (n == _unconditional_delay_slot) { 1961 #ifndef PRODUCT 1962 if (_cfg->C->trace_opto_output()) 1963 tty->print("# NodeFitsInBundle [%4d]: TRUE; is in unconditional delay slot\n", n->_idx); 1964 #endif 1965 return (true); 1966 } 1967 1968 // If the node cannot be scheduled this cycle, skip it 1969 if (_current_latency[n_idx] > _bundle_cycle_number) { 1970 #ifndef PRODUCT 1971 if (_cfg->C->trace_opto_output()) 1972 tty->print("# NodeFitsInBundle [%4d]: FALSE; latency %4d > %d\n", 1973 n->_idx, _current_latency[n_idx], _bundle_cycle_number); 1974 #endif 1975 return (false); 1976 } 1977 1978 const Pipeline *node_pipeline = n->pipeline(); 1979 1980 uint instruction_count = node_pipeline->instructionCount(); 1981 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0) 1982 instruction_count = 0; 1983 else if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot) 1984 instruction_count++; 1985 1986 if (_bundle_instr_count + instruction_count > Pipeline::_max_instrs_per_cycle) { 1987 #ifndef PRODUCT 1988 if (_cfg->C->trace_opto_output()) 1989 tty->print("# NodeFitsInBundle [%4d]: FALSE; too many instructions: %d > %d\n", 1990 n->_idx, _bundle_instr_count + instruction_count, Pipeline::_max_instrs_per_cycle); 1991 #endif 1992 return (false); 1993 } 1994 1995 // Don't allow non-machine nodes to be handled this way 1996 if (!n->is_Mach() && instruction_count == 0) 1997 return (false); 1998 1999 // See if there is any overlap 2000 uint delay = _bundle_use.full_latency(0, node_pipeline->resourceUse()); 2001 2002 if (delay > 0) { 2003 #ifndef PRODUCT 2004 if (_cfg->C->trace_opto_output()) 2005 tty->print("# NodeFitsInBundle [%4d]: FALSE; functional units overlap\n", n_idx); 2006 #endif 2007 return false; 2008 } 2009 2010 #ifndef PRODUCT 2011 if (_cfg->C->trace_opto_output()) 2012 tty->print("# NodeFitsInBundle [%4d]: TRUE\n", n_idx); 2013 #endif 2014 2015 return true; 2016 } 2017 2018 Node * Scheduling::ChooseNodeToBundle() { 2019 uint siz = _available.size(); 2020 2021 if (siz == 0) { 2022 2023 #ifndef PRODUCT 2024 if (_cfg->C->trace_opto_output()) 2025 tty->print("# ChooseNodeToBundle: NULL\n"); 2026 #endif 2027 return (NULL); 2028 } 2029 2030 // Fast path, if only 1 instruction in the bundle 2031 if (siz == 1) { 2032 #ifndef PRODUCT 2033 if (_cfg->C->trace_opto_output()) { 2034 tty->print("# ChooseNodeToBundle (only 1): "); 2035 _available[0]->dump(); 2036 } 2037 #endif 2038 return (_available[0]); 2039 } 2040 2041 // Don't bother, if the bundle is already full 2042 if (_bundle_instr_count < Pipeline::_max_instrs_per_cycle) { 2043 for ( uint i = 0; i < siz; i++ ) { 2044 Node *n = _available[i]; 2045 2046 // Skip projections, we'll handle them another way 2047 if (n->is_Proj()) 2048 continue; 2049 2050 // This presupposed that instructions are inserted into the 2051 // available list in a legality order; i.e. instructions that 2052 // must be inserted first are at the head of the list 2053 if (NodeFitsInBundle(n)) { 2054 #ifndef PRODUCT 2055 if (_cfg->C->trace_opto_output()) { 2056 tty->print("# ChooseNodeToBundle: "); 2057 n->dump(); 2058 } 2059 #endif 2060 return (n); 2061 } 2062 } 2063 } 2064 2065 // Nothing fits in this bundle, choose the highest priority 2066 #ifndef PRODUCT 2067 if (_cfg->C->trace_opto_output()) { 2068 tty->print("# ChooseNodeToBundle: "); 2069 _available[0]->dump(); 2070 } 2071 #endif 2072 2073 return _available[0]; 2074 } 2075 2076 void Scheduling::AddNodeToAvailableList(Node *n) { 2077 assert( !n->is_Proj(), "projections never directly made available" ); 2078 #ifndef PRODUCT 2079 if (_cfg->C->trace_opto_output()) { 2080 tty->print("# AddNodeToAvailableList: "); 2081 n->dump(); 2082 } 2083 #endif 2084 2085 int latency = _current_latency[n->_idx]; 2086 2087 // Insert in latency order (insertion sort) 2088 uint i; 2089 for ( i=0; i < _available.size(); i++ ) 2090 if (_current_latency[_available[i]->_idx] > latency) 2091 break; 2092 2093 // Special Check for compares following branches 2094 if( n->is_Mach() && _scheduled.size() > 0 ) { 2095 int op = n->as_Mach()->ideal_Opcode(); 2096 Node *last = _scheduled[0]; 2097 if( last->is_MachIf() && last->in(1) == n && 2098 ( op == Op_CmpI || 2099 op == Op_CmpU || 2100 op == Op_CmpP || 2101 op == Op_CmpF || 2102 op == Op_CmpD || 2103 op == Op_CmpL ) ) { 2104 2105 // Recalculate position, moving to front of same latency 2106 for ( i=0 ; i < _available.size(); i++ ) 2107 if (_current_latency[_available[i]->_idx] >= latency) 2108 break; 2109 } 2110 } 2111 2112 // Insert the node in the available list 2113 _available.insert(i, n); 2114 2115 #ifndef PRODUCT 2116 if (_cfg->C->trace_opto_output()) 2117 dump_available(); 2118 #endif 2119 } 2120 2121 void Scheduling::DecrementUseCounts(Node *n, const Block *bb) { 2122 for ( uint i=0; i < n->len(); i++ ) { 2123 Node *def = n->in(i); 2124 if (!def) continue; 2125 if( def->is_Proj() ) // If this is a machine projection, then 2126 def = def->in(0); // propagate usage thru to the base instruction 2127 2128 if(_cfg->get_block_for_node(def) != bb) { // Ignore if not block-local 2129 continue; 2130 } 2131 2132 // Compute the latency 2133 uint l = _bundle_cycle_number + n->latency(i); 2134 if (_current_latency[def->_idx] < l) 2135 _current_latency[def->_idx] = l; 2136 2137 // If this does not have uses then schedule it 2138 if ((--_uses[def->_idx]) == 0) 2139 AddNodeToAvailableList(def); 2140 } 2141 } 2142 2143 void Scheduling::AddNodeToBundle(Node *n, const Block *bb) { 2144 #ifndef PRODUCT 2145 if (_cfg->C->trace_opto_output()) { 2146 tty->print("# AddNodeToBundle: "); 2147 n->dump(); 2148 } 2149 #endif 2150 2151 // Remove this from the available list 2152 uint i; 2153 for (i = 0; i < _available.size(); i++) 2154 if (_available[i] == n) 2155 break; 2156 assert(i < _available.size(), "entry in _available list not found"); 2157 _available.remove(i); 2158 2159 // See if this fits in the current bundle 2160 const Pipeline *node_pipeline = n->pipeline(); 2161 const Pipeline_Use& node_usage = node_pipeline->resourceUse(); 2162 2163 // Check for instructions to be placed in the delay slot. We 2164 // do this before we actually schedule the current instruction, 2165 // because the delay slot follows the current instruction. 2166 if (Pipeline::_branch_has_delay_slot && 2167 node_pipeline->hasBranchDelay() && 2168 !_unconditional_delay_slot) { 2169 2170 uint siz = _available.size(); 2171 2172 // Conditional branches can support an instruction that 2173 // is unconditionally executed and not dependent by the 2174 // branch, OR a conditionally executed instruction if 2175 // the branch is taken. In practice, this means that 2176 // the first instruction at the branch target is 2177 // copied to the delay slot, and the branch goes to 2178 // the instruction after that at the branch target 2179 if ( n->is_MachBranch() ) { 2180 2181 assert( !n->is_MachNullCheck(), "should not look for delay slot for Null Check" ); 2182 assert( !n->is_Catch(), "should not look for delay slot for Catch" ); 2183 2184 #ifndef PRODUCT 2185 _branches++; 2186 #endif 2187 2188 // At least 1 instruction is on the available list 2189 // that is not dependent on the branch 2190 for (uint i = 0; i < siz; i++) { 2191 Node *d = _available[i]; 2192 const Pipeline *avail_pipeline = d->pipeline(); 2193 2194 // Don't allow safepoints in the branch shadow, that will 2195 // cause a number of difficulties 2196 if ( avail_pipeline->instructionCount() == 1 && 2197 !avail_pipeline->hasMultipleBundles() && 2198 !avail_pipeline->hasBranchDelay() && 2199 Pipeline::instr_has_unit_size() && 2200 d->size(_regalloc) == Pipeline::instr_unit_size() && 2201 NodeFitsInBundle(d) && 2202 !node_bundling(d)->used_in_delay()) { 2203 2204 if (d->is_Mach() && !d->is_MachSafePoint()) { 2205 // A node that fits in the delay slot was found, so we need to 2206 // set the appropriate bits in the bundle pipeline information so 2207 // that it correctly indicates resource usage. Later, when we 2208 // attempt to add this instruction to the bundle, we will skip 2209 // setting the resource usage. 2210 _unconditional_delay_slot = d; 2211 node_bundling(n)->set_use_unconditional_delay(); 2212 node_bundling(d)->set_used_in_unconditional_delay(); 2213 _bundle_use.add_usage(avail_pipeline->resourceUse()); 2214 _current_latency[d->_idx] = _bundle_cycle_number; 2215 _next_node = d; 2216 ++_bundle_instr_count; 2217 #ifndef PRODUCT 2218 _unconditional_delays++; 2219 #endif 2220 break; 2221 } 2222 } 2223 } 2224 } 2225 2226 // No delay slot, add a nop to the usage 2227 if (!_unconditional_delay_slot) { 2228 // See if adding an instruction in the delay slot will overflow 2229 // the bundle. 2230 if (!NodeFitsInBundle(_nop)) { 2231 #ifndef PRODUCT 2232 if (_cfg->C->trace_opto_output()) 2233 tty->print("# *** STEP(1 instruction for delay slot) ***\n"); 2234 #endif 2235 step(1); 2236 } 2237 2238 _bundle_use.add_usage(_nop->pipeline()->resourceUse()); 2239 _next_node = _nop; 2240 ++_bundle_instr_count; 2241 } 2242 2243 // See if the instruction in the delay slot requires a 2244 // step of the bundles 2245 if (!NodeFitsInBundle(n)) { 2246 #ifndef PRODUCT 2247 if (_cfg->C->trace_opto_output()) 2248 tty->print("# *** STEP(branch won't fit) ***\n"); 2249 #endif 2250 // Update the state information 2251 _bundle_instr_count = 0; 2252 _bundle_cycle_number += 1; 2253 _bundle_use.step(1); 2254 } 2255 } 2256 2257 // Get the number of instructions 2258 uint instruction_count = node_pipeline->instructionCount(); 2259 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0) 2260 instruction_count = 0; 2261 2262 // Compute the latency information 2263 uint delay = 0; 2264 2265 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) { 2266 int relative_latency = _current_latency[n->_idx] - _bundle_cycle_number; 2267 if (relative_latency < 0) 2268 relative_latency = 0; 2269 2270 delay = _bundle_use.full_latency(relative_latency, node_usage); 2271 2272 // Does not fit in this bundle, start a new one 2273 if (delay > 0) { 2274 step(delay); 2275 2276 #ifndef PRODUCT 2277 if (_cfg->C->trace_opto_output()) 2278 tty->print("# *** STEP(%d) ***\n", delay); 2279 #endif 2280 } 2281 } 2282 2283 // If this was placed in the delay slot, ignore it 2284 if (n != _unconditional_delay_slot) { 2285 2286 if (delay == 0) { 2287 if (node_pipeline->hasMultipleBundles()) { 2288 #ifndef PRODUCT 2289 if (_cfg->C->trace_opto_output()) 2290 tty->print("# *** STEP(multiple instructions) ***\n"); 2291 #endif 2292 step(1); 2293 } 2294 2295 else if (instruction_count + _bundle_instr_count > Pipeline::_max_instrs_per_cycle) { 2296 #ifndef PRODUCT 2297 if (_cfg->C->trace_opto_output()) 2298 tty->print("# *** STEP(%d >= %d instructions) ***\n", 2299 instruction_count + _bundle_instr_count, 2300 Pipeline::_max_instrs_per_cycle); 2301 #endif 2302 step(1); 2303 } 2304 } 2305 2306 if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot) 2307 _bundle_instr_count++; 2308 2309 // Set the node's latency 2310 _current_latency[n->_idx] = _bundle_cycle_number; 2311 2312 // Now merge the functional unit information 2313 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) 2314 _bundle_use.add_usage(node_usage); 2315 2316 // Increment the number of instructions in this bundle 2317 _bundle_instr_count += instruction_count; 2318 2319 // Remember this node for later 2320 if (n->is_Mach()) 2321 _next_node = n; 2322 } 2323 2324 // It's possible to have a BoxLock in the graph and in the _bbs mapping but 2325 // not in the bb->_nodes array. This happens for debug-info-only BoxLocks. 2326 // 'Schedule' them (basically ignore in the schedule) but do not insert them 2327 // into the block. All other scheduled nodes get put in the schedule here. 2328 int op = n->Opcode(); 2329 if( (op == Op_Node && n->req() == 0) || // anti-dependence node OR 2330 (op != Op_Node && // Not an unused antidepedence node and 2331 // not an unallocated boxlock 2332 (OptoReg::is_valid(_regalloc->get_reg_first(n)) || op != Op_BoxLock)) ) { 2333 2334 // Push any trailing projections 2335 if( bb->get_node(bb->number_of_nodes()-1) != n ) { 2336 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2337 Node *foi = n->fast_out(i); 2338 if( foi->is_Proj() ) 2339 _scheduled.push(foi); 2340 } 2341 } 2342 2343 // Put the instruction in the schedule list 2344 _scheduled.push(n); 2345 } 2346 2347 #ifndef PRODUCT 2348 if (_cfg->C->trace_opto_output()) 2349 dump_available(); 2350 #endif 2351 2352 // Walk all the definitions, decrementing use counts, and 2353 // if a definition has a 0 use count, place it in the available list. 2354 DecrementUseCounts(n,bb); 2355 } 2356 2357 // This method sets the use count within a basic block. We will ignore all 2358 // uses outside the current basic block. As we are doing a backwards walk, 2359 // any node we reach that has a use count of 0 may be scheduled. This also 2360 // avoids the problem of cyclic references from phi nodes, as long as phi 2361 // nodes are at the front of the basic block. This method also initializes 2362 // the available list to the set of instructions that have no uses within this 2363 // basic block. 2364 void Scheduling::ComputeUseCount(const Block *bb) { 2365 #ifndef PRODUCT 2366 if (_cfg->C->trace_opto_output()) 2367 tty->print("# -> ComputeUseCount\n"); 2368 #endif 2369 2370 // Clear the list of available and scheduled instructions, just in case 2371 _available.clear(); 2372 _scheduled.clear(); 2373 2374 // No delay slot specified 2375 _unconditional_delay_slot = NULL; 2376 2377 #ifdef ASSERT 2378 for( uint i=0; i < bb->number_of_nodes(); i++ ) 2379 assert( _uses[bb->get_node(i)->_idx] == 0, "_use array not clean" ); 2380 #endif 2381 2382 // Force the _uses count to never go to zero for unscheduable pieces 2383 // of the block 2384 for( uint k = 0; k < _bb_start; k++ ) 2385 _uses[bb->get_node(k)->_idx] = 1; 2386 for( uint l = _bb_end; l < bb->number_of_nodes(); l++ ) 2387 _uses[bb->get_node(l)->_idx] = 1; 2388 2389 // Iterate backwards over the instructions in the block. Don't count the 2390 // branch projections at end or the block header instructions. 2391 for( uint j = _bb_end-1; j >= _bb_start; j-- ) { 2392 Node *n = bb->get_node(j); 2393 if( n->is_Proj() ) continue; // Projections handled another way 2394 2395 // Account for all uses 2396 for ( uint k = 0; k < n->len(); k++ ) { 2397 Node *inp = n->in(k); 2398 if (!inp) continue; 2399 assert(inp != n, "no cycles allowed" ); 2400 if (_cfg->get_block_for_node(inp) == bb) { // Block-local use? 2401 if (inp->is_Proj()) { // Skip through Proj's 2402 inp = inp->in(0); 2403 } 2404 ++_uses[inp->_idx]; // Count 1 block-local use 2405 } 2406 } 2407 2408 // If this instruction has a 0 use count, then it is available 2409 if (!_uses[n->_idx]) { 2410 _current_latency[n->_idx] = _bundle_cycle_number; 2411 AddNodeToAvailableList(n); 2412 } 2413 2414 #ifndef PRODUCT 2415 if (_cfg->C->trace_opto_output()) { 2416 tty->print("# uses: %3d: ", _uses[n->_idx]); 2417 n->dump(); 2418 } 2419 #endif 2420 } 2421 2422 #ifndef PRODUCT 2423 if (_cfg->C->trace_opto_output()) 2424 tty->print("# <- ComputeUseCount\n"); 2425 #endif 2426 } 2427 2428 // This routine performs scheduling on each basic block in reverse order, 2429 // using instruction latencies and taking into account function unit 2430 // availability. 2431 void Scheduling::DoScheduling() { 2432 #ifndef PRODUCT 2433 if (_cfg->C->trace_opto_output()) 2434 tty->print("# -> DoScheduling\n"); 2435 #endif 2436 2437 Block *succ_bb = NULL; 2438 Block *bb; 2439 2440 // Walk over all the basic blocks in reverse order 2441 for (int i = _cfg->number_of_blocks() - 1; i >= 0; succ_bb = bb, i--) { 2442 bb = _cfg->get_block(i); 2443 2444 #ifndef PRODUCT 2445 if (_cfg->C->trace_opto_output()) { 2446 tty->print("# Schedule BB#%03d (initial)\n", i); 2447 for (uint j = 0; j < bb->number_of_nodes(); j++) { 2448 bb->get_node(j)->dump(); 2449 } 2450 } 2451 #endif 2452 2453 // On the head node, skip processing 2454 if (bb == _cfg->get_root_block()) { 2455 continue; 2456 } 2457 2458 // Skip empty, connector blocks 2459 if (bb->is_connector()) 2460 continue; 2461 2462 // If the following block is not the sole successor of 2463 // this one, then reset the pipeline information 2464 if (bb->_num_succs != 1 || bb->non_connector_successor(0) != succ_bb) { 2465 #ifndef PRODUCT 2466 if (_cfg->C->trace_opto_output()) { 2467 tty->print("*** bundle start of next BB, node %d, for %d instructions\n", 2468 _next_node->_idx, _bundle_instr_count); 2469 } 2470 #endif 2471 step_and_clear(); 2472 } 2473 2474 // Leave untouched the starting instruction, any Phis, a CreateEx node 2475 // or Top. bb->get_node(_bb_start) is the first schedulable instruction. 2476 _bb_end = bb->number_of_nodes()-1; 2477 for( _bb_start=1; _bb_start <= _bb_end; _bb_start++ ) { 2478 Node *n = bb->get_node(_bb_start); 2479 // Things not matched, like Phinodes and ProjNodes don't get scheduled. 2480 // Also, MachIdealNodes do not get scheduled 2481 if( !n->is_Mach() ) continue; // Skip non-machine nodes 2482 MachNode *mach = n->as_Mach(); 2483 int iop = mach->ideal_Opcode(); 2484 if( iop == Op_CreateEx ) continue; // CreateEx is pinned 2485 if( iop == Op_Con ) continue; // Do not schedule Top 2486 if( iop == Op_Node && // Do not schedule PhiNodes, ProjNodes 2487 mach->pipeline() == MachNode::pipeline_class() && 2488 !n->is_SpillCopy() && !n->is_MachMerge() ) // Breakpoints, Prolog, etc 2489 continue; 2490 break; // Funny loop structure to be sure... 2491 } 2492 // Compute last "interesting" instruction in block - last instruction we 2493 // might schedule. _bb_end points just after last schedulable inst. We 2494 // normally schedule conditional branches (despite them being forced last 2495 // in the block), because they have delay slots we can fill. Calls all 2496 // have their delay slots filled in the template expansions, so we don't 2497 // bother scheduling them. 2498 Node *last = bb->get_node(_bb_end); 2499 // Ignore trailing NOPs. 2500 while (_bb_end > 0 && last->is_Mach() && 2501 last->as_Mach()->ideal_Opcode() == Op_Con) { 2502 last = bb->get_node(--_bb_end); 2503 } 2504 assert(!last->is_Mach() || last->as_Mach()->ideal_Opcode() != Op_Con, ""); 2505 if( last->is_Catch() || 2506 // Exclude unreachable path case when Halt node is in a separate block. 2507 (_bb_end > 1 && last->is_Mach() && last->as_Mach()->ideal_Opcode() == Op_Halt) ) { 2508 // There must be a prior call. Skip it. 2509 while( !bb->get_node(--_bb_end)->is_MachCall() ) { 2510 assert( bb->get_node(_bb_end)->is_MachProj(), "skipping projections after expected call" ); 2511 } 2512 } else if( last->is_MachNullCheck() ) { 2513 // Backup so the last null-checked memory instruction is 2514 // outside the schedulable range. Skip over the nullcheck, 2515 // projection, and the memory nodes. 2516 Node *mem = last->in(1); 2517 do { 2518 _bb_end--; 2519 } while (mem != bb->get_node(_bb_end)); 2520 } else { 2521 // Set _bb_end to point after last schedulable inst. 2522 _bb_end++; 2523 } 2524 2525 assert( _bb_start <= _bb_end, "inverted block ends" ); 2526 2527 // Compute the register antidependencies for the basic block 2528 ComputeRegisterAntidependencies(bb); 2529 if (_cfg->C->failing()) return; // too many D-U pinch points 2530 2531 // Compute intra-bb latencies for the nodes 2532 ComputeLocalLatenciesForward(bb); 2533 2534 // Compute the usage within the block, and set the list of all nodes 2535 // in the block that have no uses within the block. 2536 ComputeUseCount(bb); 2537 2538 // Schedule the remaining instructions in the block 2539 while ( _available.size() > 0 ) { 2540 Node *n = ChooseNodeToBundle(); 2541 guarantee(n != NULL, "no nodes available"); 2542 AddNodeToBundle(n,bb); 2543 } 2544 2545 assert( _scheduled.size() == _bb_end - _bb_start, "wrong number of instructions" ); 2546 #ifdef ASSERT 2547 for( uint l = _bb_start; l < _bb_end; l++ ) { 2548 Node *n = bb->get_node(l); 2549 uint m; 2550 for( m = 0; m < _bb_end-_bb_start; m++ ) 2551 if( _scheduled[m] == n ) 2552 break; 2553 assert( m < _bb_end-_bb_start, "instruction missing in schedule" ); 2554 } 2555 #endif 2556 2557 // Now copy the instructions (in reverse order) back to the block 2558 for ( uint k = _bb_start; k < _bb_end; k++ ) 2559 bb->map_node(_scheduled[_bb_end-k-1], k); 2560 2561 #ifndef PRODUCT 2562 if (_cfg->C->trace_opto_output()) { 2563 tty->print("# Schedule BB#%03d (final)\n", i); 2564 uint current = 0; 2565 for (uint j = 0; j < bb->number_of_nodes(); j++) { 2566 Node *n = bb->get_node(j); 2567 if( valid_bundle_info(n) ) { 2568 Bundle *bundle = node_bundling(n); 2569 if (bundle->instr_count() > 0 || bundle->flags() > 0) { 2570 tty->print("*** Bundle: "); 2571 bundle->dump(); 2572 } 2573 n->dump(); 2574 } 2575 } 2576 } 2577 #endif 2578 #ifdef ASSERT 2579 verify_good_schedule(bb,"after block local scheduling"); 2580 #endif 2581 } 2582 2583 #ifndef PRODUCT 2584 if (_cfg->C->trace_opto_output()) 2585 tty->print("# <- DoScheduling\n"); 2586 #endif 2587 2588 // Record final node-bundling array location 2589 _regalloc->C->set_node_bundling_base(_node_bundling_base); 2590 2591 } // end DoScheduling 2592 2593 // Verify that no live-range used in the block is killed in the block by a 2594 // wrong DEF. This doesn't verify live-ranges that span blocks. 2595 2596 // Check for edge existence. Used to avoid adding redundant precedence edges. 2597 static bool edge_from_to( Node *from, Node *to ) { 2598 for( uint i=0; i<from->len(); i++ ) 2599 if( from->in(i) == to ) 2600 return true; 2601 return false; 2602 } 2603 2604 #ifdef ASSERT 2605 void Scheduling::verify_do_def( Node *n, OptoReg::Name def, const char *msg ) { 2606 // Check for bad kills 2607 if( OptoReg::is_valid(def) ) { // Ignore stores & control flow 2608 Node *prior_use = _reg_node[def]; 2609 if( prior_use && !edge_from_to(prior_use,n) ) { 2610 tty->print("%s = ",OptoReg::as_VMReg(def)->name()); 2611 n->dump(); 2612 tty->print_cr("..."); 2613 prior_use->dump(); 2614 assert(edge_from_to(prior_use,n),msg); 2615 } 2616 _reg_node.map(def,NULL); // Kill live USEs 2617 } 2618 } 2619 2620 void Scheduling::verify_good_schedule( Block *b, const char *msg ) { 2621 2622 // Zap to something reasonable for the verify code 2623 _reg_node.clear(); 2624 2625 // Walk over the block backwards. Check to make sure each DEF doesn't 2626 // kill a live value (other than the one it's supposed to). Add each 2627 // USE to the live set. 2628 for( uint i = b->number_of_nodes()-1; i >= _bb_start; i-- ) { 2629 Node *n = b->get_node(i); 2630 int n_op = n->Opcode(); 2631 if( n_op == Op_MachProj && n->ideal_reg() == MachProjNode::fat_proj ) { 2632 // Fat-proj kills a slew of registers 2633 RegMask rm = n->out_RegMask();// Make local copy 2634 while( rm.is_NotEmpty() ) { 2635 OptoReg::Name kill = rm.find_first_elem(); 2636 rm.Remove(kill); 2637 verify_do_def( n, kill, msg ); 2638 } 2639 } else if( n_op != Op_Node ) { // Avoid brand new antidependence nodes 2640 // Get DEF'd registers the normal way 2641 verify_do_def( n, _regalloc->get_reg_first(n), msg ); 2642 verify_do_def( n, _regalloc->get_reg_second(n), msg ); 2643 } 2644 2645 // Now make all USEs live 2646 for( uint i=1; i<n->req(); i++ ) { 2647 Node *def = n->in(i); 2648 assert(def != 0, "input edge required"); 2649 OptoReg::Name reg_lo = _regalloc->get_reg_first(def); 2650 OptoReg::Name reg_hi = _regalloc->get_reg_second(def); 2651 if( OptoReg::is_valid(reg_lo) ) { 2652 assert(!_reg_node[reg_lo] || edge_from_to(_reg_node[reg_lo],def), msg); 2653 _reg_node.map(reg_lo,n); 2654 } 2655 if( OptoReg::is_valid(reg_hi) ) { 2656 assert(!_reg_node[reg_hi] || edge_from_to(_reg_node[reg_hi],def), msg); 2657 _reg_node.map(reg_hi,n); 2658 } 2659 } 2660 2661 } 2662 2663 // Zap to something reasonable for the Antidependence code 2664 _reg_node.clear(); 2665 } 2666 #endif 2667 2668 // Conditionally add precedence edges. Avoid putting edges on Projs. 2669 static void add_prec_edge_from_to( Node *from, Node *to ) { 2670 if( from->is_Proj() ) { // Put precedence edge on Proj's input 2671 assert( from->req() == 1 && (from->len() == 1 || from->in(1)==0), "no precedence edges on projections" ); 2672 from = from->in(0); 2673 } 2674 if( from != to && // No cycles (for things like LD L0,[L0+4] ) 2675 !edge_from_to( from, to ) ) // Avoid duplicate edge 2676 from->add_prec(to); 2677 } 2678 2679 void Scheduling::anti_do_def( Block *b, Node *def, OptoReg::Name def_reg, int is_def ) { 2680 if( !OptoReg::is_valid(def_reg) ) // Ignore stores & control flow 2681 return; 2682 2683 Node *pinch = _reg_node[def_reg]; // Get pinch point 2684 if ((pinch == NULL) || _cfg->get_block_for_node(pinch) != b || // No pinch-point yet? 2685 is_def ) { // Check for a true def (not a kill) 2686 _reg_node.map(def_reg,def); // Record def/kill as the optimistic pinch-point 2687 return; 2688 } 2689 2690 Node *kill = def; // Rename 'def' to more descriptive 'kill' 2691 debug_only( def = (Node*)0xdeadbeef; ) 2692 2693 // After some number of kills there _may_ be a later def 2694 Node *later_def = NULL; 2695 2696 // Finding a kill requires a real pinch-point. 2697 // Check for not already having a pinch-point. 2698 // Pinch points are Op_Node's. 2699 if( pinch->Opcode() != Op_Node ) { // Or later-def/kill as pinch-point? 2700 later_def = pinch; // Must be def/kill as optimistic pinch-point 2701 if ( _pinch_free_list.size() > 0) { 2702 pinch = _pinch_free_list.pop(); 2703 } else { 2704 pinch = new Node(1); // Pinch point to-be 2705 } 2706 if (pinch->_idx >= _regalloc->node_regs_max_index()) { 2707 _cfg->C->record_method_not_compilable("too many D-U pinch points"); 2708 return; 2709 } 2710 _cfg->map_node_to_block(pinch, b); // Pretend it's valid in this block (lazy init) 2711 _reg_node.map(def_reg,pinch); // Record pinch-point 2712 //_regalloc->set_bad(pinch->_idx); // Already initialized this way. 2713 if( later_def->outcnt() == 0 || later_def->ideal_reg() == MachProjNode::fat_proj ) { // Distinguish def from kill 2714 pinch->init_req(0, _cfg->C->top()); // set not NULL for the next call 2715 add_prec_edge_from_to(later_def,pinch); // Add edge from kill to pinch 2716 later_def = NULL; // and no later def 2717 } 2718 pinch->set_req(0,later_def); // Hook later def so we can find it 2719 } else { // Else have valid pinch point 2720 if( pinch->in(0) ) // If there is a later-def 2721 later_def = pinch->in(0); // Get it 2722 } 2723 2724 // Add output-dependence edge from later def to kill 2725 if( later_def ) // If there is some original def 2726 add_prec_edge_from_to(later_def,kill); // Add edge from def to kill 2727 2728 // See if current kill is also a use, and so is forced to be the pinch-point. 2729 if( pinch->Opcode() == Op_Node ) { 2730 Node *uses = kill->is_Proj() ? kill->in(0) : kill; 2731 for( uint i=1; i<uses->req(); i++ ) { 2732 if( _regalloc->get_reg_first(uses->in(i)) == def_reg || 2733 _regalloc->get_reg_second(uses->in(i)) == def_reg ) { 2734 // Yes, found a use/kill pinch-point 2735 pinch->set_req(0,NULL); // 2736 pinch->replace_by(kill); // Move anti-dep edges up 2737 pinch = kill; 2738 _reg_node.map(def_reg,pinch); 2739 return; 2740 } 2741 } 2742 } 2743 2744 // Add edge from kill to pinch-point 2745 add_prec_edge_from_to(kill,pinch); 2746 } 2747 2748 void Scheduling::anti_do_use( Block *b, Node *use, OptoReg::Name use_reg ) { 2749 if( !OptoReg::is_valid(use_reg) ) // Ignore stores & control flow 2750 return; 2751 Node *pinch = _reg_node[use_reg]; // Get pinch point 2752 // Check for no later def_reg/kill in block 2753 if ((pinch != NULL) && _cfg->get_block_for_node(pinch) == b && 2754 // Use has to be block-local as well 2755 _cfg->get_block_for_node(use) == b) { 2756 if( pinch->Opcode() == Op_Node && // Real pinch-point (not optimistic?) 2757 pinch->req() == 1 ) { // pinch not yet in block? 2758 pinch->del_req(0); // yank pointer to later-def, also set flag 2759 // Insert the pinch-point in the block just after the last use 2760 b->insert_node(pinch, b->find_node(use) + 1); 2761 _bb_end++; // Increase size scheduled region in block 2762 } 2763 2764 add_prec_edge_from_to(pinch,use); 2765 } 2766 } 2767 2768 // We insert antidependences between the reads and following write of 2769 // allocated registers to prevent illegal code motion. Hopefully, the 2770 // number of added references should be fairly small, especially as we 2771 // are only adding references within the current basic block. 2772 void Scheduling::ComputeRegisterAntidependencies(Block *b) { 2773 2774 #ifdef ASSERT 2775 verify_good_schedule(b,"before block local scheduling"); 2776 #endif 2777 2778 // A valid schedule, for each register independently, is an endless cycle 2779 // of: a def, then some uses (connected to the def by true dependencies), 2780 // then some kills (defs with no uses), finally the cycle repeats with a new 2781 // def. The uses are allowed to float relative to each other, as are the 2782 // kills. No use is allowed to slide past a kill (or def). This requires 2783 // antidependencies between all uses of a single def and all kills that 2784 // follow, up to the next def. More edges are redundant, because later defs 2785 // & kills are already serialized with true or antidependencies. To keep 2786 // the edge count down, we add a 'pinch point' node if there's more than 2787 // one use or more than one kill/def. 2788 2789 // We add dependencies in one bottom-up pass. 2790 2791 // For each instruction we handle it's DEFs/KILLs, then it's USEs. 2792 2793 // For each DEF/KILL, we check to see if there's a prior DEF/KILL for this 2794 // register. If not, we record the DEF/KILL in _reg_node, the 2795 // register-to-def mapping. If there is a prior DEF/KILL, we insert a 2796 // "pinch point", a new Node that's in the graph but not in the block. 2797 // We put edges from the prior and current DEF/KILLs to the pinch point. 2798 // We put the pinch point in _reg_node. If there's already a pinch point 2799 // we merely add an edge from the current DEF/KILL to the pinch point. 2800 2801 // After doing the DEF/KILLs, we handle USEs. For each used register, we 2802 // put an edge from the pinch point to the USE. 2803 2804 // To be expedient, the _reg_node array is pre-allocated for the whole 2805 // compilation. _reg_node is lazily initialized; it either contains a NULL, 2806 // or a valid def/kill/pinch-point, or a leftover node from some prior 2807 // block. Leftover node from some prior block is treated like a NULL (no 2808 // prior def, so no anti-dependence needed). Valid def is distinguished by 2809 // it being in the current block. 2810 bool fat_proj_seen = false; 2811 uint last_safept = _bb_end-1; 2812 Node* end_node = (_bb_end-1 >= _bb_start) ? b->get_node(last_safept) : NULL; 2813 Node* last_safept_node = end_node; 2814 for( uint i = _bb_end-1; i >= _bb_start; i-- ) { 2815 Node *n = b->get_node(i); 2816 int is_def = n->outcnt(); // def if some uses prior to adding precedence edges 2817 if( n->is_MachProj() && n->ideal_reg() == MachProjNode::fat_proj ) { 2818 // Fat-proj kills a slew of registers 2819 // This can add edges to 'n' and obscure whether or not it was a def, 2820 // hence the is_def flag. 2821 fat_proj_seen = true; 2822 RegMask rm = n->out_RegMask();// Make local copy 2823 while( rm.is_NotEmpty() ) { 2824 OptoReg::Name kill = rm.find_first_elem(); 2825 rm.Remove(kill); 2826 anti_do_def( b, n, kill, is_def ); 2827 } 2828 } else { 2829 // Get DEF'd registers the normal way 2830 anti_do_def( b, n, _regalloc->get_reg_first(n), is_def ); 2831 anti_do_def( b, n, _regalloc->get_reg_second(n), is_def ); 2832 } 2833 2834 // Kill projections on a branch should appear to occur on the 2835 // branch, not afterwards, so grab the masks from the projections 2836 // and process them. 2837 if (n->is_MachBranch() || n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_Jump) { 2838 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2839 Node* use = n->fast_out(i); 2840 if (use->is_Proj()) { 2841 RegMask rm = use->out_RegMask();// Make local copy 2842 while( rm.is_NotEmpty() ) { 2843 OptoReg::Name kill = rm.find_first_elem(); 2844 rm.Remove(kill); 2845 anti_do_def( b, n, kill, false ); 2846 } 2847 } 2848 } 2849 } 2850 2851 // Check each register used by this instruction for a following DEF/KILL 2852 // that must occur afterward and requires an anti-dependence edge. 2853 for( uint j=0; j<n->req(); j++ ) { 2854 Node *def = n->in(j); 2855 if( def ) { 2856 assert( !def->is_MachProj() || def->ideal_reg() != MachProjNode::fat_proj, "" ); 2857 anti_do_use( b, n, _regalloc->get_reg_first(def) ); 2858 anti_do_use( b, n, _regalloc->get_reg_second(def) ); 2859 } 2860 } 2861 // Do not allow defs of new derived values to float above GC 2862 // points unless the base is definitely available at the GC point. 2863 2864 Node *m = b->get_node(i); 2865 2866 // Add precedence edge from following safepoint to use of derived pointer 2867 if( last_safept_node != end_node && 2868 m != last_safept_node) { 2869 for (uint k = 1; k < m->req(); k++) { 2870 const Type *t = m->in(k)->bottom_type(); 2871 if( t->isa_oop_ptr() && 2872 t->is_ptr()->offset() != 0 ) { 2873 last_safept_node->add_prec( m ); 2874 break; 2875 } 2876 } 2877 } 2878 2879 if( n->jvms() ) { // Precedence edge from derived to safept 2880 // Check if last_safept_node was moved by pinch-point insertion in anti_do_use() 2881 if( b->get_node(last_safept) != last_safept_node ) { 2882 last_safept = b->find_node(last_safept_node); 2883 } 2884 for( uint j=last_safept; j > i; j-- ) { 2885 Node *mach = b->get_node(j); 2886 if( mach->is_Mach() && mach->as_Mach()->ideal_Opcode() == Op_AddP ) 2887 mach->add_prec( n ); 2888 } 2889 last_safept = i; 2890 last_safept_node = m; 2891 } 2892 } 2893 2894 if (fat_proj_seen) { 2895 // Garbage collect pinch nodes that were not consumed. 2896 // They are usually created by a fat kill MachProj for a call. 2897 garbage_collect_pinch_nodes(); 2898 } 2899 } 2900 2901 // Garbage collect pinch nodes for reuse by other blocks. 2902 // 2903 // The block scheduler's insertion of anti-dependence 2904 // edges creates many pinch nodes when the block contains 2905 // 2 or more Calls. A pinch node is used to prevent a 2906 // combinatorial explosion of edges. If a set of kills for a 2907 // register is anti-dependent on a set of uses (or defs), rather 2908 // than adding an edge in the graph between each pair of kill 2909 // and use (or def), a pinch is inserted between them: 2910 // 2911 // use1 use2 use3 2912 // \ | / 2913 // \ | / 2914 // pinch 2915 // / | \ 2916 // / | \ 2917 // kill1 kill2 kill3 2918 // 2919 // One pinch node is created per register killed when 2920 // the second call is encountered during a backwards pass 2921 // over the block. Most of these pinch nodes are never 2922 // wired into the graph because the register is never 2923 // used or def'ed in the block. 2924 // 2925 void Scheduling::garbage_collect_pinch_nodes() { 2926 #ifndef PRODUCT 2927 if (_cfg->C->trace_opto_output()) tty->print("Reclaimed pinch nodes:"); 2928 #endif 2929 int trace_cnt = 0; 2930 for (uint k = 0; k < _reg_node.Size(); k++) { 2931 Node* pinch = _reg_node[k]; 2932 if ((pinch != NULL) && pinch->Opcode() == Op_Node && 2933 // no predecence input edges 2934 (pinch->req() == pinch->len() || pinch->in(pinch->req()) == NULL) ) { 2935 cleanup_pinch(pinch); 2936 _pinch_free_list.push(pinch); 2937 _reg_node.map(k, NULL); 2938 #ifndef PRODUCT 2939 if (_cfg->C->trace_opto_output()) { 2940 trace_cnt++; 2941 if (trace_cnt > 40) { 2942 tty->print("\n"); 2943 trace_cnt = 0; 2944 } 2945 tty->print(" %d", pinch->_idx); 2946 } 2947 #endif 2948 } 2949 } 2950 #ifndef PRODUCT 2951 if (_cfg->C->trace_opto_output()) tty->print("\n"); 2952 #endif 2953 } 2954 2955 // Clean up a pinch node for reuse. 2956 void Scheduling::cleanup_pinch( Node *pinch ) { 2957 assert (pinch && pinch->Opcode() == Op_Node && pinch->req() == 1, "just checking"); 2958 2959 for (DUIterator_Last imin, i = pinch->last_outs(imin); i >= imin; ) { 2960 Node* use = pinch->last_out(i); 2961 uint uses_found = 0; 2962 for (uint j = use->req(); j < use->len(); j++) { 2963 if (use->in(j) == pinch) { 2964 use->rm_prec(j); 2965 uses_found++; 2966 } 2967 } 2968 assert(uses_found > 0, "must be a precedence edge"); 2969 i -= uses_found; // we deleted 1 or more copies of this edge 2970 } 2971 // May have a later_def entry 2972 pinch->set_req(0, NULL); 2973 } 2974 2975 #ifndef PRODUCT 2976 2977 void Scheduling::dump_available() const { 2978 tty->print("#Availist "); 2979 for (uint i = 0; i < _available.size(); i++) 2980 tty->print(" N%d/l%d", _available[i]->_idx,_current_latency[_available[i]->_idx]); 2981 tty->cr(); 2982 } 2983 2984 // Print Scheduling Statistics 2985 void Scheduling::print_statistics() { 2986 // Print the size added by nops for bundling 2987 tty->print("Nops added %d bytes to total of %d bytes", 2988 _total_nop_size, _total_method_size); 2989 if (_total_method_size > 0) 2990 tty->print(", for %.2f%%", 2991 ((double)_total_nop_size) / ((double) _total_method_size) * 100.0); 2992 tty->print("\n"); 2993 2994 // Print the number of branch shadows filled 2995 if (Pipeline::_branch_has_delay_slot) { 2996 tty->print("Of %d branches, %d had unconditional delay slots filled", 2997 _total_branches, _total_unconditional_delays); 2998 if (_total_branches > 0) 2999 tty->print(", for %.2f%%", 3000 ((double)_total_unconditional_delays) / ((double)_total_branches) * 100.0); 3001 tty->print("\n"); 3002 } 3003 3004 uint total_instructions = 0, total_bundles = 0; 3005 3006 for (uint i = 1; i <= Pipeline::_max_instrs_per_cycle; i++) { 3007 uint bundle_count = _total_instructions_per_bundle[i]; 3008 total_instructions += bundle_count * i; 3009 total_bundles += bundle_count; 3010 } 3011 3012 if (total_bundles > 0) 3013 tty->print("Average ILP (excluding nops) is %.2f\n", 3014 ((double)total_instructions) / ((double)total_bundles)); 3015 } 3016 #endif