1 /* 2 * Copyright (c) 1998, 2010, 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/debugInfo.hpp" 28 #include "code/debugInfoRec.hpp" 29 #include "compiler/compileBroker.hpp" 30 #include "compiler/oopMap.hpp" 31 #include "memory/allocation.inline.hpp" 32 #include "opto/callnode.hpp" 33 #include "opto/cfgnode.hpp" 34 #include "opto/locknode.hpp" 35 #include "opto/machnode.hpp" 36 #include "opto/output.hpp" 37 #include "opto/regalloc.hpp" 38 #include "opto/runtime.hpp" 39 #include "opto/subnode.hpp" 40 #include "opto/type.hpp" 41 #include "runtime/handles.inline.hpp" 42 #include "utilities/xmlstream.hpp" 43 44 extern uint size_java_to_interp(); 45 extern uint reloc_java_to_interp(); 46 extern uint size_exception_handler(); 47 extern uint size_deopt_handler(); 48 49 #ifndef PRODUCT 50 #define DEBUG_ARG(x) , x 51 #else 52 #define DEBUG_ARG(x) 53 #endif 54 55 extern int emit_exception_handler(CodeBuffer &cbuf); 56 extern int emit_deopt_handler(CodeBuffer &cbuf); 57 58 //------------------------------Output----------------------------------------- 59 // Convert Nodes to instruction bits and pass off to the VM 60 void Compile::Output() { 61 // RootNode goes 62 assert( _cfg->_broot->_nodes.size() == 0, "" ); 63 64 // Initialize the space for the BufferBlob used to find and verify 65 // instruction size in MachNode::emit_size() 66 init_scratch_buffer_blob(); 67 if (failing()) return; // Out of memory 68 69 // The number of new nodes (mostly MachNop) is proportional to 70 // the number of java calls and inner loops which are aligned. 71 if ( C->check_node_count((NodeLimitFudgeFactor + C->java_calls()*3 + 72 C->inner_loops()*(OptoLoopAlignment-1)), 73 "out of nodes before code generation" ) ) { 74 return; 75 } 76 // Make sure I can find the Start Node 77 Block_Array& bbs = _cfg->_bbs; 78 Block *entry = _cfg->_blocks[1]; 79 Block *broot = _cfg->_broot; 80 81 const StartNode *start = entry->_nodes[0]->as_Start(); 82 83 // Replace StartNode with prolog 84 MachPrologNode *prolog = new (this) MachPrologNode(); 85 entry->_nodes.map( 0, prolog ); 86 bbs.map( prolog->_idx, entry ); 87 bbs.map( start->_idx, NULL ); // start is no longer in any block 88 89 // Virtual methods need an unverified entry point 90 91 if( is_osr_compilation() ) { 92 if( PoisonOSREntry ) { 93 // TODO: Should use a ShouldNotReachHereNode... 94 _cfg->insert( broot, 0, new (this) MachBreakpointNode() ); 95 } 96 } else { 97 if( _method && !_method->flags().is_static() ) { 98 // Insert unvalidated entry point 99 _cfg->insert( broot, 0, new (this) MachUEPNode() ); 100 } 101 102 } 103 104 105 // Break before main entry point 106 if( (_method && _method->break_at_execute()) 107 #ifndef PRODUCT 108 ||(OptoBreakpoint && is_method_compilation()) 109 ||(OptoBreakpointOSR && is_osr_compilation()) 110 ||(OptoBreakpointC2R && !_method) 111 #endif 112 ) { 113 // checking for _method means that OptoBreakpoint does not apply to 114 // runtime stubs or frame converters 115 _cfg->insert( entry, 1, new (this) MachBreakpointNode() ); 116 } 117 118 // Insert epilogs before every return 119 for( uint i=0; i<_cfg->_num_blocks; i++ ) { 120 Block *b = _cfg->_blocks[i]; 121 if( !b->is_connector() && b->non_connector_successor(0) == _cfg->_broot ) { // Found a program exit point? 122 Node *m = b->end(); 123 if( m->is_Mach() && m->as_Mach()->ideal_Opcode() != Op_Halt ) { 124 MachEpilogNode *epilog = new (this) MachEpilogNode(m->as_Mach()->ideal_Opcode() == Op_Return); 125 b->add_inst( epilog ); 126 bbs.map(epilog->_idx, b); 127 //_regalloc->set_bad(epilog->_idx); // Already initialized this way. 128 } 129 } 130 } 131 132 # ifdef ENABLE_ZAP_DEAD_LOCALS 133 if ( ZapDeadCompiledLocals ) Insert_zap_nodes(); 134 # endif 135 136 ScheduleAndBundle(); 137 138 #ifndef PRODUCT 139 if (trace_opto_output()) { 140 tty->print("\n---- After ScheduleAndBundle ----\n"); 141 for (uint i = 0; i < _cfg->_num_blocks; i++) { 142 tty->print("\nBB#%03d:\n", i); 143 Block *bb = _cfg->_blocks[i]; 144 for (uint j = 0; j < bb->_nodes.size(); j++) { 145 Node *n = bb->_nodes[j]; 146 OptoReg::Name reg = _regalloc->get_reg_first(n); 147 tty->print(" %-6s ", reg >= 0 && reg < REG_COUNT ? Matcher::regName[reg] : ""); 148 n->dump(); 149 } 150 } 151 } 152 #endif 153 154 if (failing()) return; 155 156 BuildOopMaps(); 157 158 if (failing()) return; 159 160 Fill_buffer(); 161 } 162 163 bool Compile::need_stack_bang(int frame_size_in_bytes) const { 164 // Determine if we need to generate a stack overflow check. 165 // Do it if the method is not a stub function and 166 // has java calls or has frame size > vm_page_size/8. 167 return (stub_function() == NULL && 168 (has_java_calls() || frame_size_in_bytes > os::vm_page_size()>>3)); 169 } 170 171 bool Compile::need_register_stack_bang() const { 172 // Determine if we need to generate a register stack overflow check. 173 // This is only used on architectures which have split register 174 // and memory stacks (ie. IA64). 175 // Bang if the method is not a stub function and has java calls 176 return (stub_function() == NULL && has_java_calls()); 177 } 178 179 # ifdef ENABLE_ZAP_DEAD_LOCALS 180 181 182 // In order to catch compiler oop-map bugs, we have implemented 183 // a debugging mode called ZapDeadCompilerLocals. 184 // This mode causes the compiler to insert a call to a runtime routine, 185 // "zap_dead_locals", right before each place in compiled code 186 // that could potentially be a gc-point (i.e., a safepoint or oop map point). 187 // The runtime routine checks that locations mapped as oops are really 188 // oops, that locations mapped as values do not look like oops, 189 // and that locations mapped as dead are not used later 190 // (by zapping them to an invalid address). 191 192 int Compile::_CompiledZap_count = 0; 193 194 void Compile::Insert_zap_nodes() { 195 bool skip = false; 196 197 198 // Dink with static counts because code code without the extra 199 // runtime calls is MUCH faster for debugging purposes 200 201 if ( CompileZapFirst == 0 ) ; // nothing special 202 else if ( CompileZapFirst > CompiledZap_count() ) skip = true; 203 else if ( CompileZapFirst == CompiledZap_count() ) 204 warning("starting zap compilation after skipping"); 205 206 if ( CompileZapLast == -1 ) ; // nothing special 207 else if ( CompileZapLast < CompiledZap_count() ) skip = true; 208 else if ( CompileZapLast == CompiledZap_count() ) 209 warning("about to compile last zap"); 210 211 ++_CompiledZap_count; // counts skipped zaps, too 212 213 if ( skip ) return; 214 215 216 if ( _method == NULL ) 217 return; // no safepoints/oopmaps emitted for calls in stubs,so we don't care 218 219 // Insert call to zap runtime stub before every node with an oop map 220 for( uint i=0; i<_cfg->_num_blocks; i++ ) { 221 Block *b = _cfg->_blocks[i]; 222 for ( uint j = 0; j < b->_nodes.size(); ++j ) { 223 Node *n = b->_nodes[j]; 224 225 // Determining if we should insert a zap-a-lot node in output. 226 // We do that for all nodes that has oopmap info, except for calls 227 // to allocation. Calls to allocation passes in the old top-of-eden pointer 228 // and expect the C code to reset it. Hence, there can be no safepoints between 229 // the inlined-allocation and the call to new_Java, etc. 230 // We also cannot zap monitor calls, as they must hold the microlock 231 // during the call to Zap, which also wants to grab the microlock. 232 bool insert = n->is_MachSafePoint() && (n->as_MachSafePoint()->oop_map() != NULL); 233 if ( insert ) { // it is MachSafePoint 234 if ( !n->is_MachCall() ) { 235 insert = false; 236 } else if ( n->is_MachCall() ) { 237 MachCallNode* call = n->as_MachCall(); 238 if (call->entry_point() == OptoRuntime::new_instance_Java() || 239 call->entry_point() == OptoRuntime::new_array_Java() || 240 call->entry_point() == OptoRuntime::multianewarray2_Java() || 241 call->entry_point() == OptoRuntime::multianewarray3_Java() || 242 call->entry_point() == OptoRuntime::multianewarray4_Java() || 243 call->entry_point() == OptoRuntime::multianewarray5_Java() || 244 call->entry_point() == OptoRuntime::slow_arraycopy_Java() || 245 call->entry_point() == OptoRuntime::complete_monitor_locking_Java() 246 ) { 247 insert = false; 248 } 249 } 250 if (insert) { 251 Node *zap = call_zap_node(n->as_MachSafePoint(), i); 252 b->_nodes.insert( j, zap ); 253 _cfg->_bbs.map( zap->_idx, b ); 254 ++j; 255 } 256 } 257 } 258 } 259 } 260 261 262 Node* Compile::call_zap_node(MachSafePointNode* node_to_check, int block_no) { 263 const TypeFunc *tf = OptoRuntime::zap_dead_locals_Type(); 264 CallStaticJavaNode* ideal_node = 265 new (this, tf->domain()->cnt()) CallStaticJavaNode( tf, 266 OptoRuntime::zap_dead_locals_stub(_method->flags().is_native()), 267 "call zap dead locals stub", 0, TypePtr::BOTTOM); 268 // We need to copy the OopMap from the site we're zapping at. 269 // We have to make a copy, because the zap site might not be 270 // a call site, and zap_dead is a call site. 271 OopMap* clone = node_to_check->oop_map()->deep_copy(); 272 273 // Add the cloned OopMap to the zap node 274 ideal_node->set_oop_map(clone); 275 return _matcher->match_sfpt(ideal_node); 276 } 277 278 //------------------------------is_node_getting_a_safepoint-------------------- 279 bool Compile::is_node_getting_a_safepoint( Node* n) { 280 // This code duplicates the logic prior to the call of add_safepoint 281 // below in this file. 282 if( n->is_MachSafePoint() ) return true; 283 return false; 284 } 285 286 # endif // ENABLE_ZAP_DEAD_LOCALS 287 288 //------------------------------compute_loop_first_inst_sizes------------------ 289 // Compute the size of first NumberOfLoopInstrToAlign instructions at the top 290 // of a loop. When aligning a loop we need to provide enough instructions 291 // in cpu's fetch buffer to feed decoders. The loop alignment could be 292 // avoided if we have enough instructions in fetch buffer at the head of a loop. 293 // By default, the size is set to 999999 by Block's constructor so that 294 // a loop will be aligned if the size is not reset here. 295 // 296 // Note: Mach instructions could contain several HW instructions 297 // so the size is estimated only. 298 // 299 void Compile::compute_loop_first_inst_sizes() { 300 // The next condition is used to gate the loop alignment optimization. 301 // Don't aligned a loop if there are enough instructions at the head of a loop 302 // or alignment padding is larger then MaxLoopPad. By default, MaxLoopPad 303 // is equal to OptoLoopAlignment-1 except on new Intel cpus, where it is 304 // equal to 11 bytes which is the largest address NOP instruction. 305 if( MaxLoopPad < OptoLoopAlignment-1 ) { 306 uint last_block = _cfg->_num_blocks-1; 307 for( uint i=1; i <= last_block; i++ ) { 308 Block *b = _cfg->_blocks[i]; 309 // Check the first loop's block which requires an alignment. 310 if( b->loop_alignment() > (uint)relocInfo::addr_unit() ) { 311 uint sum_size = 0; 312 uint inst_cnt = NumberOfLoopInstrToAlign; 313 inst_cnt = b->compute_first_inst_size(sum_size, inst_cnt, _regalloc); 314 315 // Check subsequent fallthrough blocks if the loop's first 316 // block(s) does not have enough instructions. 317 Block *nb = b; 318 while( inst_cnt > 0 && 319 i < last_block && 320 !_cfg->_blocks[i+1]->has_loop_alignment() && 321 !nb->has_successor(b) ) { 322 i++; 323 nb = _cfg->_blocks[i]; 324 inst_cnt = nb->compute_first_inst_size(sum_size, inst_cnt, _regalloc); 325 } // while( inst_cnt > 0 && i < last_block ) 326 327 b->set_first_inst_size(sum_size); 328 } // f( b->head()->is_Loop() ) 329 } // for( i <= last_block ) 330 } // if( MaxLoopPad < OptoLoopAlignment-1 ) 331 } 332 333 //----------------------Shorten_branches--------------------------------------- 334 // The architecture description provides short branch variants for some long 335 // branch instructions. Replace eligible long branches with short branches. 336 void Compile::Shorten_branches(Label *labels, int& code_size, int& reloc_size, int& stub_size, int& const_size) { 337 338 // fill in the nop array for bundling computations 339 MachNode *_nop_list[Bundle::_nop_count]; 340 Bundle::initialize_nops(_nop_list, this); 341 342 // ------------------ 343 // Compute size of each block, method size, and relocation information size 344 uint *jmp_end = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks); 345 uint *blk_starts = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks+1); 346 DEBUG_ONLY( uint *jmp_target = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks); ) 347 DEBUG_ONLY( uint *jmp_rule = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks); ) 348 blk_starts[0] = 0; 349 350 // Initialize the sizes to 0 351 code_size = 0; // Size in bytes of generated code 352 stub_size = 0; // Size in bytes of all stub entries 353 // Size in bytes of all relocation entries, including those in local stubs. 354 // Start with 2-bytes of reloc info for the unvalidated entry point 355 reloc_size = 1; // Number of relocation entries 356 const_size = 0; // size of fp constants in words 357 358 // Make three passes. The first computes pessimistic blk_starts, 359 // relative jmp_end, reloc_size and const_size information. 360 // The second performs short branch substitution using the pessimistic 361 // sizing. The third inserts nops where needed. 362 363 Node *nj; // tmp 364 365 // Step one, perform a pessimistic sizing pass. 366 uint i; 367 uint min_offset_from_last_call = 1; // init to a positive value 368 uint nop_size = (new (this) MachNopNode())->size(_regalloc); 369 for( i=0; i<_cfg->_num_blocks; i++ ) { // For all blocks 370 Block *b = _cfg->_blocks[i]; 371 372 // Sum all instruction sizes to compute block size 373 uint last_inst = b->_nodes.size(); 374 uint blk_size = 0; 375 for( uint j = 0; j<last_inst; j++ ) { 376 nj = b->_nodes[j]; 377 uint inst_size = nj->size(_regalloc); 378 blk_size += inst_size; 379 // Handle machine instruction nodes 380 if( nj->is_Mach() ) { 381 MachNode *mach = nj->as_Mach(); 382 blk_size += (mach->alignment_required() - 1) * relocInfo::addr_unit(); // assume worst case padding 383 reloc_size += mach->reloc(); 384 const_size += mach->const_size(); 385 if( mach->is_MachCall() ) { 386 MachCallNode *mcall = mach->as_MachCall(); 387 // This destination address is NOT PC-relative 388 389 mcall->method_set((intptr_t)mcall->entry_point()); 390 391 if( mcall->is_MachCallJava() && mcall->as_MachCallJava()->_method ) { 392 stub_size += size_java_to_interp(); 393 reloc_size += reloc_java_to_interp(); 394 } 395 } else if (mach->is_MachSafePoint()) { 396 // If call/safepoint are adjacent, account for possible 397 // nop to disambiguate the two safepoints. 398 if (min_offset_from_last_call == 0) { 399 blk_size += nop_size; 400 } 401 } else if (mach->ideal_Opcode() == Op_Jump) { 402 const_size += b->_num_succs; // Address table size 403 // The size is valid even for 64 bit since it is 404 // multiplied by 2*jintSize on this method exit. 405 } 406 } 407 min_offset_from_last_call += inst_size; 408 // Remember end of call offset 409 if (nj->is_MachCall() && nj->as_MachCall()->is_safepoint_node()) { 410 min_offset_from_last_call = 0; 411 } 412 } 413 414 // During short branch replacement, we store the relative (to blk_starts) 415 // end of jump in jmp_end, rather than the absolute end of jump. This 416 // is so that we do not need to recompute sizes of all nodes when we compute 417 // correct blk_starts in our next sizing pass. 418 jmp_end[i] = blk_size; 419 DEBUG_ONLY( jmp_target[i] = 0; ) 420 421 // When the next block starts a loop, we may insert pad NOP 422 // instructions. Since we cannot know our future alignment, 423 // assume the worst. 424 if( i<_cfg->_num_blocks-1 ) { 425 Block *nb = _cfg->_blocks[i+1]; 426 int max_loop_pad = nb->code_alignment()-relocInfo::addr_unit(); 427 if( max_loop_pad > 0 ) { 428 assert(is_power_of_2(max_loop_pad+relocInfo::addr_unit()), ""); 429 blk_size += max_loop_pad; 430 } 431 } 432 433 // Save block size; update total method size 434 blk_starts[i+1] = blk_starts[i]+blk_size; 435 } 436 437 // Step two, replace eligible long jumps. 438 439 // Note: this will only get the long branches within short branch 440 // range. Another pass might detect more branches that became 441 // candidates because the shortening in the first pass exposed 442 // more opportunities. Unfortunately, this would require 443 // recomputing the starting and ending positions for the blocks 444 for( i=0; i<_cfg->_num_blocks; i++ ) { 445 Block *b = _cfg->_blocks[i]; 446 447 int j; 448 // Find the branch; ignore trailing NOPs. 449 for( j = b->_nodes.size()-1; j>=0; j-- ) { 450 nj = b->_nodes[j]; 451 if( !nj->is_Mach() || nj->as_Mach()->ideal_Opcode() != Op_Con ) 452 break; 453 } 454 455 if (j >= 0) { 456 if( nj->is_Mach() && nj->as_Mach()->may_be_short_branch() ) { 457 MachNode *mach = nj->as_Mach(); 458 // This requires the TRUE branch target be in succs[0] 459 uint bnum = b->non_connector_successor(0)->_pre_order; 460 uintptr_t target = blk_starts[bnum]; 461 if( mach->is_pc_relative() ) { 462 int offset = target-(blk_starts[i] + jmp_end[i]); 463 if (_matcher->is_short_branch_offset(mach->rule(), offset)) { 464 // We've got a winner. Replace this branch. 465 MachNode* replacement = mach->short_branch_version(this); 466 b->_nodes.map(j, replacement); 467 mach->subsume_by(replacement); 468 469 // Update the jmp_end size to save time in our 470 // next pass. 471 jmp_end[i] -= (mach->size(_regalloc) - replacement->size(_regalloc)); 472 DEBUG_ONLY( jmp_target[i] = bnum; ); 473 DEBUG_ONLY( jmp_rule[i] = mach->rule(); ); 474 } 475 } else { 476 #ifndef PRODUCT 477 mach->dump(3); 478 #endif 479 Unimplemented(); 480 } 481 } 482 } 483 } 484 485 // Compute the size of first NumberOfLoopInstrToAlign instructions at head 486 // of a loop. It is used to determine the padding for loop alignment. 487 compute_loop_first_inst_sizes(); 488 489 // Step 3, compute the offsets of all the labels 490 uint last_call_adr = max_uint; 491 for( i=0; i<_cfg->_num_blocks; i++ ) { // For all blocks 492 // copy the offset of the beginning to the corresponding label 493 assert(labels[i].is_unused(), "cannot patch at this point"); 494 labels[i].bind_loc(blk_starts[i], CodeBuffer::SECT_INSTS); 495 496 // insert padding for any instructions that need it 497 Block *b = _cfg->_blocks[i]; 498 uint last_inst = b->_nodes.size(); 499 uint adr = blk_starts[i]; 500 for( uint j = 0; j<last_inst; j++ ) { 501 nj = b->_nodes[j]; 502 if( nj->is_Mach() ) { 503 int padding = nj->as_Mach()->compute_padding(adr); 504 // If call/safepoint are adjacent insert a nop (5010568) 505 if (padding == 0 && nj->is_MachSafePoint() && !nj->is_MachCall() && 506 adr == last_call_adr ) { 507 padding = nop_size; 508 } 509 if(padding > 0) { 510 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size"); 511 int nops_cnt = padding / nop_size; 512 MachNode *nop = new (this) MachNopNode(nops_cnt); 513 b->_nodes.insert(j++, nop); 514 _cfg->_bbs.map( nop->_idx, b ); 515 adr += padding; 516 last_inst++; 517 } 518 } 519 adr += nj->size(_regalloc); 520 521 // Remember end of call offset 522 if (nj->is_MachCall() && nj->as_MachCall()->is_safepoint_node()) { 523 last_call_adr = adr; 524 } 525 } 526 527 if ( i != _cfg->_num_blocks-1) { 528 // Get the size of the block 529 uint blk_size = adr - blk_starts[i]; 530 531 // When the next block is the top of a loop, we may insert pad NOP 532 // instructions. 533 Block *nb = _cfg->_blocks[i+1]; 534 int current_offset = blk_starts[i] + blk_size; 535 current_offset += nb->alignment_padding(current_offset); 536 // Save block size; update total method size 537 blk_starts[i+1] = current_offset; 538 } 539 } 540 541 #ifdef ASSERT 542 for( i=0; i<_cfg->_num_blocks; i++ ) { // For all blocks 543 if( jmp_target[i] != 0 ) { 544 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_end[i]); 545 if (!_matcher->is_short_branch_offset(jmp_rule[i], offset)) { 546 tty->print_cr("target (%d) - jmp_end(%d) = offset (%d), jmp_block B%d, target_block B%d", blk_starts[jmp_target[i]], blk_starts[i] + jmp_end[i], offset, i, jmp_target[i]); 547 } 548 assert(_matcher->is_short_branch_offset(jmp_rule[i], offset), "Displacement too large for short jmp"); 549 } 550 } 551 #endif 552 553 // ------------------ 554 // Compute size for code buffer 555 code_size = blk_starts[i-1] + jmp_end[i-1]; 556 557 // Relocation records 558 reloc_size += 1; // Relo entry for exception handler 559 560 // Adjust reloc_size to number of record of relocation info 561 // Min is 2 bytes, max is probably 6 or 8, with a tax up to 25% for 562 // a relocation index. 563 // The CodeBuffer will expand the locs array if this estimate is too low. 564 reloc_size *= 10 / sizeof(relocInfo); 565 566 // Adjust const_size to number of bytes 567 const_size *= 2*jintSize; // both float and double take two words per entry 568 569 } 570 571 //------------------------------FillLocArray----------------------------------- 572 // Create a bit of debug info and append it to the array. The mapping is from 573 // Java local or expression stack to constant, register or stack-slot. For 574 // doubles, insert 2 mappings and return 1 (to tell the caller that the next 575 // entry has been taken care of and caller should skip it). 576 static LocationValue *new_loc_value( PhaseRegAlloc *ra, OptoReg::Name regnum, Location::Type l_type ) { 577 // This should never have accepted Bad before 578 assert(OptoReg::is_valid(regnum), "location must be valid"); 579 return (OptoReg::is_reg(regnum)) 580 ? new LocationValue(Location::new_reg_loc(l_type, OptoReg::as_VMReg(regnum)) ) 581 : new LocationValue(Location::new_stk_loc(l_type, ra->reg2offset(regnum))); 582 } 583 584 585 ObjectValue* 586 Compile::sv_for_node_id(GrowableArray<ScopeValue*> *objs, int id) { 587 for (int i = 0; i < objs->length(); i++) { 588 assert(objs->at(i)->is_object(), "corrupt object cache"); 589 ObjectValue* sv = (ObjectValue*) objs->at(i); 590 if (sv->id() == id) { 591 return sv; 592 } 593 } 594 // Otherwise.. 595 return NULL; 596 } 597 598 void Compile::set_sv_for_object_node(GrowableArray<ScopeValue*> *objs, 599 ObjectValue* sv ) { 600 assert(sv_for_node_id(objs, sv->id()) == NULL, "Precondition"); 601 objs->append(sv); 602 } 603 604 605 void Compile::FillLocArray( int idx, MachSafePointNode* sfpt, Node *local, 606 GrowableArray<ScopeValue*> *array, 607 GrowableArray<ScopeValue*> *objs ) { 608 assert( local, "use _top instead of null" ); 609 if (array->length() != idx) { 610 assert(array->length() == idx + 1, "Unexpected array count"); 611 // Old functionality: 612 // return 613 // New functionality: 614 // Assert if the local is not top. In product mode let the new node 615 // override the old entry. 616 assert(local == top(), "LocArray collision"); 617 if (local == top()) { 618 return; 619 } 620 array->pop(); 621 } 622 const Type *t = local->bottom_type(); 623 624 // Is it a safepoint scalar object node? 625 if (local->is_SafePointScalarObject()) { 626 SafePointScalarObjectNode* spobj = local->as_SafePointScalarObject(); 627 628 ObjectValue* sv = Compile::sv_for_node_id(objs, spobj->_idx); 629 if (sv == NULL) { 630 ciKlass* cik = t->is_oopptr()->klass(); 631 assert(cik->is_instance_klass() || 632 cik->is_array_klass(), "Not supported allocation."); 633 sv = new ObjectValue(spobj->_idx, 634 new ConstantOopWriteValue(cik->constant_encoding())); 635 Compile::set_sv_for_object_node(objs, sv); 636 637 uint first_ind = spobj->first_index(); 638 for (uint i = 0; i < spobj->n_fields(); i++) { 639 Node* fld_node = sfpt->in(first_ind+i); 640 (void)FillLocArray(sv->field_values()->length(), sfpt, fld_node, sv->field_values(), objs); 641 } 642 } 643 array->append(sv); 644 return; 645 } 646 647 // Grab the register number for the local 648 OptoReg::Name regnum = _regalloc->get_reg_first(local); 649 if( OptoReg::is_valid(regnum) ) {// Got a register/stack? 650 // Record the double as two float registers. 651 // The register mask for such a value always specifies two adjacent 652 // float registers, with the lower register number even. 653 // Normally, the allocation of high and low words to these registers 654 // is irrelevant, because nearly all operations on register pairs 655 // (e.g., StoreD) treat them as a single unit. 656 // Here, we assume in addition that the words in these two registers 657 // stored "naturally" (by operations like StoreD and double stores 658 // within the interpreter) such that the lower-numbered register 659 // is written to the lower memory address. This may seem like 660 // a machine dependency, but it is not--it is a requirement on 661 // the author of the <arch>.ad file to ensure that, for every 662 // even/odd double-register pair to which a double may be allocated, 663 // the word in the even single-register is stored to the first 664 // memory word. (Note that register numbers are completely 665 // arbitrary, and are not tied to any machine-level encodings.) 666 #ifdef _LP64 667 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon ) { 668 array->append(new ConstantIntValue(0)); 669 array->append(new_loc_value( _regalloc, regnum, Location::dbl )); 670 } else if ( t->base() == Type::Long ) { 671 array->append(new ConstantIntValue(0)); 672 array->append(new_loc_value( _regalloc, regnum, Location::lng )); 673 } else if ( t->base() == Type::RawPtr ) { 674 // jsr/ret return address which must be restored into a the full 675 // width 64-bit stack slot. 676 array->append(new_loc_value( _regalloc, regnum, Location::lng )); 677 } 678 #else //_LP64 679 #ifdef SPARC 680 if (t->base() == Type::Long && OptoReg::is_reg(regnum)) { 681 // For SPARC we have to swap high and low words for 682 // long values stored in a single-register (g0-g7). 683 array->append(new_loc_value( _regalloc, regnum , Location::normal )); 684 array->append(new_loc_value( _regalloc, OptoReg::add(regnum,1), Location::normal )); 685 } else 686 #endif //SPARC 687 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon || t->base() == Type::Long ) { 688 // Repack the double/long as two jints. 689 // The convention the interpreter uses is that the second local 690 // holds the first raw word of the native double representation. 691 // This is actually reasonable, since locals and stack arrays 692 // grow downwards in all implementations. 693 // (If, on some machine, the interpreter's Java locals or stack 694 // were to grow upwards, the embedded doubles would be word-swapped.) 695 array->append(new_loc_value( _regalloc, OptoReg::add(regnum,1), Location::normal )); 696 array->append(new_loc_value( _regalloc, regnum , Location::normal )); 697 } 698 #endif //_LP64 699 else if( (t->base() == Type::FloatBot || t->base() == Type::FloatCon) && 700 OptoReg::is_reg(regnum) ) { 701 array->append(new_loc_value( _regalloc, regnum, Matcher::float_in_double() 702 ? Location::float_in_dbl : Location::normal )); 703 } else if( t->base() == Type::Int && OptoReg::is_reg(regnum) ) { 704 array->append(new_loc_value( _regalloc, regnum, Matcher::int_in_long 705 ? Location::int_in_long : Location::normal )); 706 } else if( t->base() == Type::NarrowOop ) { 707 array->append(new_loc_value( _regalloc, regnum, Location::narrowoop )); 708 } else { 709 array->append(new_loc_value( _regalloc, regnum, _regalloc->is_oop(local) ? Location::oop : Location::normal )); 710 } 711 return; 712 } 713 714 // No register. It must be constant data. 715 switch (t->base()) { 716 case Type::Half: // Second half of a double 717 ShouldNotReachHere(); // Caller should skip 2nd halves 718 break; 719 case Type::AnyPtr: 720 array->append(new ConstantOopWriteValue(NULL)); 721 break; 722 case Type::AryPtr: 723 case Type::InstPtr: 724 case Type::KlassPtr: // fall through 725 array->append(new ConstantOopWriteValue(t->isa_oopptr()->const_oop()->constant_encoding())); 726 break; 727 case Type::NarrowOop: 728 if (t == TypeNarrowOop::NULL_PTR) { 729 array->append(new ConstantOopWriteValue(NULL)); 730 } else { 731 array->append(new ConstantOopWriteValue(t->make_ptr()->isa_oopptr()->const_oop()->constant_encoding())); 732 } 733 break; 734 case Type::Int: 735 array->append(new ConstantIntValue(t->is_int()->get_con())); 736 break; 737 case Type::RawPtr: 738 // A return address (T_ADDRESS). 739 assert((intptr_t)t->is_ptr()->get_con() < (intptr_t)0x10000, "must be a valid BCI"); 740 #ifdef _LP64 741 // Must be restored to the full-width 64-bit stack slot. 742 array->append(new ConstantLongValue(t->is_ptr()->get_con())); 743 #else 744 array->append(new ConstantIntValue(t->is_ptr()->get_con())); 745 #endif 746 break; 747 case Type::FloatCon: { 748 float f = t->is_float_constant()->getf(); 749 array->append(new ConstantIntValue(jint_cast(f))); 750 break; 751 } 752 case Type::DoubleCon: { 753 jdouble d = t->is_double_constant()->getd(); 754 #ifdef _LP64 755 array->append(new ConstantIntValue(0)); 756 array->append(new ConstantDoubleValue(d)); 757 #else 758 // Repack the double as two jints. 759 // The convention the interpreter uses is that the second local 760 // holds the first raw word of the native double representation. 761 // This is actually reasonable, since locals and stack arrays 762 // grow downwards in all implementations. 763 // (If, on some machine, the interpreter's Java locals or stack 764 // were to grow upwards, the embedded doubles would be word-swapped.) 765 jint *dp = (jint*)&d; 766 array->append(new ConstantIntValue(dp[1])); 767 array->append(new ConstantIntValue(dp[0])); 768 #endif 769 break; 770 } 771 case Type::Long: { 772 jlong d = t->is_long()->get_con(); 773 #ifdef _LP64 774 array->append(new ConstantIntValue(0)); 775 array->append(new ConstantLongValue(d)); 776 #else 777 // Repack the long as two jints. 778 // The convention the interpreter uses is that the second local 779 // holds the first raw word of the native double representation. 780 // This is actually reasonable, since locals and stack arrays 781 // grow downwards in all implementations. 782 // (If, on some machine, the interpreter's Java locals or stack 783 // were to grow upwards, the embedded doubles would be word-swapped.) 784 jint *dp = (jint*)&d; 785 array->append(new ConstantIntValue(dp[1])); 786 array->append(new ConstantIntValue(dp[0])); 787 #endif 788 break; 789 } 790 case Type::Top: // Add an illegal value here 791 array->append(new LocationValue(Location())); 792 break; 793 default: 794 ShouldNotReachHere(); 795 break; 796 } 797 } 798 799 // Determine if this node starts a bundle 800 bool Compile::starts_bundle(const Node *n) const { 801 return (_node_bundling_limit > n->_idx && 802 _node_bundling_base[n->_idx].starts_bundle()); 803 } 804 805 //--------------------------Process_OopMap_Node-------------------------------- 806 void Compile::Process_OopMap_Node(MachNode *mach, int current_offset) { 807 808 // Handle special safepoint nodes for synchronization 809 MachSafePointNode *sfn = mach->as_MachSafePoint(); 810 MachCallNode *mcall; 811 812 #ifdef ENABLE_ZAP_DEAD_LOCALS 813 assert( is_node_getting_a_safepoint(mach), "logic does not match; false negative"); 814 #endif 815 816 int safepoint_pc_offset = current_offset; 817 bool is_method_handle_invoke = false; 818 bool return_oop = false; 819 820 // Add the safepoint in the DebugInfoRecorder 821 if( !mach->is_MachCall() ) { 822 mcall = NULL; 823 debug_info()->add_safepoint(safepoint_pc_offset, sfn->_oop_map); 824 } else { 825 mcall = mach->as_MachCall(); 826 827 // Is the call a MethodHandle call? 828 if (mcall->is_MachCallJava()) { 829 if (mcall->as_MachCallJava()->_method_handle_invoke) { 830 assert(has_method_handle_invokes(), "must have been set during call generation"); 831 is_method_handle_invoke = true; 832 } 833 } 834 835 // Check if a call returns an object. 836 if (mcall->return_value_is_used() && 837 mcall->tf()->range()->field_at(TypeFunc::Parms)->isa_ptr()) { 838 return_oop = true; 839 } 840 safepoint_pc_offset += mcall->ret_addr_offset(); 841 debug_info()->add_safepoint(safepoint_pc_offset, mcall->_oop_map); 842 } 843 844 // Loop over the JVMState list to add scope information 845 // Do not skip safepoints with a NULL method, they need monitor info 846 JVMState* youngest_jvms = sfn->jvms(); 847 int max_depth = youngest_jvms->depth(); 848 849 // Allocate the object pool for scalar-replaced objects -- the map from 850 // small-integer keys (which can be recorded in the local and ostack 851 // arrays) to descriptions of the object state. 852 GrowableArray<ScopeValue*> *objs = new GrowableArray<ScopeValue*>(); 853 854 // Visit scopes from oldest to youngest. 855 for (int depth = 1; depth <= max_depth; depth++) { 856 JVMState* jvms = youngest_jvms->of_depth(depth); 857 int idx; 858 ciMethod* method = jvms->has_method() ? jvms->method() : NULL; 859 // Safepoints that do not have method() set only provide oop-map and monitor info 860 // to support GC; these do not support deoptimization. 861 int num_locs = (method == NULL) ? 0 : jvms->loc_size(); 862 int num_exps = (method == NULL) ? 0 : jvms->stk_size(); 863 int num_mon = jvms->nof_monitors(); 864 assert(method == NULL || jvms->bci() < 0 || num_locs == method->max_locals(), 865 "JVMS local count must match that of the method"); 866 867 // Add Local and Expression Stack Information 868 869 // Insert locals into the locarray 870 GrowableArray<ScopeValue*> *locarray = new GrowableArray<ScopeValue*>(num_locs); 871 for( idx = 0; idx < num_locs; idx++ ) { 872 FillLocArray( idx, sfn, sfn->local(jvms, idx), locarray, objs ); 873 } 874 875 // Insert expression stack entries into the exparray 876 GrowableArray<ScopeValue*> *exparray = new GrowableArray<ScopeValue*>(num_exps); 877 for( idx = 0; idx < num_exps; idx++ ) { 878 FillLocArray( idx, sfn, sfn->stack(jvms, idx), exparray, objs ); 879 } 880 881 // Add in mappings of the monitors 882 assert( !method || 883 !method->is_synchronized() || 884 method->is_native() || 885 num_mon > 0 || 886 !GenerateSynchronizationCode, 887 "monitors must always exist for synchronized methods"); 888 889 // Build the growable array of ScopeValues for exp stack 890 GrowableArray<MonitorValue*> *monarray = new GrowableArray<MonitorValue*>(num_mon); 891 892 // Loop over monitors and insert into array 893 for(idx = 0; idx < num_mon; idx++) { 894 // Grab the node that defines this monitor 895 Node* box_node = sfn->monitor_box(jvms, idx); 896 Node* obj_node = sfn->monitor_obj(jvms, idx); 897 898 // Create ScopeValue for object 899 ScopeValue *scval = NULL; 900 901 if( obj_node->is_SafePointScalarObject() ) { 902 SafePointScalarObjectNode* spobj = obj_node->as_SafePointScalarObject(); 903 scval = Compile::sv_for_node_id(objs, spobj->_idx); 904 if (scval == NULL) { 905 const Type *t = obj_node->bottom_type(); 906 ciKlass* cik = t->is_oopptr()->klass(); 907 assert(cik->is_instance_klass() || 908 cik->is_array_klass(), "Not supported allocation."); 909 ObjectValue* sv = new ObjectValue(spobj->_idx, 910 new ConstantOopWriteValue(cik->constant_encoding())); 911 Compile::set_sv_for_object_node(objs, sv); 912 913 uint first_ind = spobj->first_index(); 914 for (uint i = 0; i < spobj->n_fields(); i++) { 915 Node* fld_node = sfn->in(first_ind+i); 916 (void)FillLocArray(sv->field_values()->length(), sfn, fld_node, sv->field_values(), objs); 917 } 918 scval = sv; 919 } 920 } else if( !obj_node->is_Con() ) { 921 OptoReg::Name obj_reg = _regalloc->get_reg_first(obj_node); 922 if( obj_node->bottom_type()->base() == Type::NarrowOop ) { 923 scval = new_loc_value( _regalloc, obj_reg, Location::narrowoop ); 924 } else { 925 scval = new_loc_value( _regalloc, obj_reg, Location::oop ); 926 } 927 } else { 928 const TypePtr *tp = obj_node->bottom_type()->make_ptr(); 929 scval = new ConstantOopWriteValue(tp->is_instptr()->const_oop()->constant_encoding()); 930 } 931 932 OptoReg::Name box_reg = BoxLockNode::stack_slot(box_node); 933 Location basic_lock = Location::new_stk_loc(Location::normal,_regalloc->reg2offset(box_reg)); 934 while( !box_node->is_BoxLock() ) box_node = box_node->in(1); 935 monarray->append(new MonitorValue(scval, basic_lock, box_node->as_BoxLock()->is_eliminated())); 936 } 937 938 // We dump the object pool first, since deoptimization reads it in first. 939 debug_info()->dump_object_pool(objs); 940 941 // Build first class objects to pass to scope 942 DebugToken *locvals = debug_info()->create_scope_values(locarray); 943 DebugToken *expvals = debug_info()->create_scope_values(exparray); 944 DebugToken *monvals = debug_info()->create_monitor_values(monarray); 945 946 // Make method available for all Safepoints 947 ciMethod* scope_method = method ? method : _method; 948 // Describe the scope here 949 assert(jvms->bci() >= InvocationEntryBci && jvms->bci() <= 0x10000, "must be a valid or entry BCI"); 950 assert(!jvms->should_reexecute() || depth == max_depth, "reexecute allowed only for the youngest"); 951 // Now we can describe the scope. 952 debug_info()->describe_scope(safepoint_pc_offset, scope_method, jvms->bci(), jvms->should_reexecute(), is_method_handle_invoke, return_oop, locvals, expvals, monvals); 953 } // End jvms loop 954 955 // Mark the end of the scope set. 956 debug_info()->end_safepoint(safepoint_pc_offset); 957 } 958 959 960 961 // A simplified version of Process_OopMap_Node, to handle non-safepoints. 962 class NonSafepointEmitter { 963 Compile* C; 964 JVMState* _pending_jvms; 965 int _pending_offset; 966 967 void emit_non_safepoint(); 968 969 public: 970 NonSafepointEmitter(Compile* compile) { 971 this->C = compile; 972 _pending_jvms = NULL; 973 _pending_offset = 0; 974 } 975 976 void observe_instruction(Node* n, int pc_offset) { 977 if (!C->debug_info()->recording_non_safepoints()) return; 978 979 Node_Notes* nn = C->node_notes_at(n->_idx); 980 if (nn == NULL || nn->jvms() == NULL) return; 981 if (_pending_jvms != NULL && 982 _pending_jvms->same_calls_as(nn->jvms())) { 983 // Repeated JVMS? Stretch it up here. 984 _pending_offset = pc_offset; 985 } else { 986 if (_pending_jvms != NULL && 987 _pending_offset < pc_offset) { 988 emit_non_safepoint(); 989 } 990 _pending_jvms = NULL; 991 if (pc_offset > C->debug_info()->last_pc_offset()) { 992 // This is the only way _pending_jvms can become non-NULL: 993 _pending_jvms = nn->jvms(); 994 _pending_offset = pc_offset; 995 } 996 } 997 } 998 999 // Stay out of the way of real safepoints: 1000 void observe_safepoint(JVMState* jvms, int pc_offset) { 1001 if (_pending_jvms != NULL && 1002 !_pending_jvms->same_calls_as(jvms) && 1003 _pending_offset < pc_offset) { 1004 emit_non_safepoint(); 1005 } 1006 _pending_jvms = NULL; 1007 } 1008 1009 void flush_at_end() { 1010 if (_pending_jvms != NULL) { 1011 emit_non_safepoint(); 1012 } 1013 _pending_jvms = NULL; 1014 } 1015 }; 1016 1017 void NonSafepointEmitter::emit_non_safepoint() { 1018 JVMState* youngest_jvms = _pending_jvms; 1019 int pc_offset = _pending_offset; 1020 1021 // Clear it now: 1022 _pending_jvms = NULL; 1023 1024 DebugInformationRecorder* debug_info = C->debug_info(); 1025 assert(debug_info->recording_non_safepoints(), "sanity"); 1026 1027 debug_info->add_non_safepoint(pc_offset); 1028 int max_depth = youngest_jvms->depth(); 1029 1030 // Visit scopes from oldest to youngest. 1031 for (int depth = 1; depth <= max_depth; depth++) { 1032 JVMState* jvms = youngest_jvms->of_depth(depth); 1033 ciMethod* method = jvms->has_method() ? jvms->method() : NULL; 1034 assert(!jvms->should_reexecute() || depth==max_depth, "reexecute allowed only for the youngest"); 1035 debug_info->describe_scope(pc_offset, method, jvms->bci(), jvms->should_reexecute()); 1036 } 1037 1038 // Mark the end of the scope set. 1039 debug_info->end_non_safepoint(pc_offset); 1040 } 1041 1042 1043 1044 // helper for Fill_buffer bailout logic 1045 static void turn_off_compiler(Compile* C) { 1046 if (CodeCache::unallocated_capacity() >= CodeCacheMinimumFreeSpace*10) { 1047 // Do not turn off compilation if a single giant method has 1048 // blown the code cache size. 1049 C->record_failure("excessive request to CodeCache"); 1050 } else { 1051 // Let CompilerBroker disable further compilations. 1052 C->record_failure("CodeCache is full"); 1053 } 1054 } 1055 1056 1057 //------------------------------Fill_buffer------------------------------------ 1058 void Compile::Fill_buffer() { 1059 1060 // Set the initially allocated size 1061 int code_req = initial_code_capacity; 1062 int locs_req = initial_locs_capacity; 1063 int stub_req = TraceJumps ? initial_stub_capacity * 10 : initial_stub_capacity; 1064 int const_req = initial_const_capacity; 1065 bool labels_not_set = true; 1066 1067 int pad_req = NativeCall::instruction_size; 1068 // The extra spacing after the code is necessary on some platforms. 1069 // Sometimes we need to patch in a jump after the last instruction, 1070 // if the nmethod has been deoptimized. (See 4932387, 4894843.) 1071 1072 uint i; 1073 // Compute the byte offset where we can store the deopt pc. 1074 if (fixed_slots() != 0) { 1075 _orig_pc_slot_offset_in_bytes = _regalloc->reg2offset(OptoReg::stack2reg(_orig_pc_slot)); 1076 } 1077 1078 // Compute prolog code size 1079 _method_size = 0; 1080 _frame_slots = OptoReg::reg2stack(_matcher->_old_SP)+_regalloc->_framesize; 1081 #ifdef IA64 1082 if (save_argument_registers()) { 1083 // 4815101: this is a stub with implicit and unknown precision fp args. 1084 // The usual spill mechanism can only generate stfd's in this case, which 1085 // doesn't work if the fp reg to spill contains a single-precision denorm. 1086 // Instead, we hack around the normal spill mechanism using stfspill's and 1087 // ldffill's in the MachProlog and MachEpilog emit methods. We allocate 1088 // space here for the fp arg regs (f8-f15) we're going to thusly spill. 1089 // 1090 // If we ever implement 16-byte 'registers' == stack slots, we can 1091 // get rid of this hack and have SpillCopy generate stfspill/ldffill 1092 // instead of stfd/stfs/ldfd/ldfs. 1093 _frame_slots += 8*(16/BytesPerInt); 1094 } 1095 #endif 1096 assert( _frame_slots >= 0 && _frame_slots < 1000000, "sanity check" ); 1097 1098 // Create an array of unused labels, one for each basic block 1099 Label *blk_labels = NEW_RESOURCE_ARRAY(Label, _cfg->_num_blocks+1); 1100 1101 for( i=0; i <= _cfg->_num_blocks; i++ ) { 1102 blk_labels[i].init(); 1103 } 1104 1105 // If this machine supports different size branch offsets, then pre-compute 1106 // the length of the blocks 1107 if( _matcher->is_short_branch_offset(-1, 0) ) { 1108 Shorten_branches(blk_labels, code_req, locs_req, stub_req, const_req); 1109 labels_not_set = false; 1110 } 1111 1112 // nmethod and CodeBuffer count stubs & constants as part of method's code. 1113 int exception_handler_req = size_exception_handler(); 1114 int deopt_handler_req = size_deopt_handler(); 1115 exception_handler_req += MAX_stubs_size; // add marginal slop for handler 1116 deopt_handler_req += MAX_stubs_size; // add marginal slop for handler 1117 stub_req += MAX_stubs_size; // ensure per-stub margin 1118 code_req += MAX_inst_size; // ensure per-instruction margin 1119 1120 if (StressCodeBuffers) 1121 code_req = const_req = stub_req = exception_handler_req = deopt_handler_req = 0x10; // force expansion 1122 1123 int total_req = 1124 code_req + 1125 pad_req + 1126 stub_req + 1127 exception_handler_req + 1128 deopt_handler_req + // deopt handler 1129 const_req; 1130 1131 if (has_method_handle_invokes()) 1132 total_req += deopt_handler_req; // deopt MH handler 1133 1134 CodeBuffer* cb = code_buffer(); 1135 cb->initialize(total_req, locs_req); 1136 1137 // Have we run out of code space? 1138 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { 1139 turn_off_compiler(this); 1140 return; 1141 } 1142 // Configure the code buffer. 1143 cb->initialize_consts_size(const_req); 1144 cb->initialize_stubs_size(stub_req); 1145 cb->initialize_oop_recorder(env()->oop_recorder()); 1146 1147 // fill in the nop array for bundling computations 1148 MachNode *_nop_list[Bundle::_nop_count]; 1149 Bundle::initialize_nops(_nop_list, this); 1150 1151 // Create oopmap set. 1152 _oop_map_set = new OopMapSet(); 1153 1154 // !!!!! This preserves old handling of oopmaps for now 1155 debug_info()->set_oopmaps(_oop_map_set); 1156 1157 // Count and start of implicit null check instructions 1158 uint inct_cnt = 0; 1159 uint *inct_starts = NEW_RESOURCE_ARRAY(uint, _cfg->_num_blocks+1); 1160 1161 // Count and start of calls 1162 uint *call_returns = NEW_RESOURCE_ARRAY(uint, _cfg->_num_blocks+1); 1163 1164 uint return_offset = 0; 1165 int nop_size = (new (this) MachNopNode())->size(_regalloc); 1166 1167 int previous_offset = 0; 1168 int current_offset = 0; 1169 int last_call_offset = -1; 1170 1171 // Create an array of unused labels, one for each basic block, if printing is enabled 1172 #ifndef PRODUCT 1173 int *node_offsets = NULL; 1174 uint node_offset_limit = unique(); 1175 1176 1177 if ( print_assembly() ) 1178 node_offsets = NEW_RESOURCE_ARRAY(int, node_offset_limit); 1179 #endif 1180 1181 NonSafepointEmitter non_safepoints(this); // emit non-safepoints lazily 1182 1183 // ------------------ 1184 // Now fill in the code buffer 1185 Node *delay_slot = NULL; 1186 1187 for( i=0; i < _cfg->_num_blocks; i++ ) { 1188 Block *b = _cfg->_blocks[i]; 1189 1190 Node *head = b->head(); 1191 1192 // If this block needs to start aligned (i.e, can be reached other 1193 // than by falling-thru from the previous block), then force the 1194 // start of a new bundle. 1195 if( Pipeline::requires_bundling() && starts_bundle(head) ) 1196 cb->flush_bundle(true); 1197 1198 // Define the label at the beginning of the basic block 1199 if( labels_not_set ) 1200 MacroAssembler(cb).bind( blk_labels[b->_pre_order] ); 1201 1202 else 1203 assert( blk_labels[b->_pre_order].loc_pos() == cb->insts_size(), 1204 "label position does not match code offset" ); 1205 1206 uint last_inst = b->_nodes.size(); 1207 1208 // Emit block normally, except for last instruction. 1209 // Emit means "dump code bits into code buffer". 1210 for( uint j = 0; j<last_inst; j++ ) { 1211 1212 // Get the node 1213 Node* n = b->_nodes[j]; 1214 1215 // See if delay slots are supported 1216 if (valid_bundle_info(n) && 1217 node_bundling(n)->used_in_unconditional_delay()) { 1218 assert(delay_slot == NULL, "no use of delay slot node"); 1219 assert(n->size(_regalloc) == Pipeline::instr_unit_size(), "delay slot instruction wrong size"); 1220 1221 delay_slot = n; 1222 continue; 1223 } 1224 1225 // If this starts a new instruction group, then flush the current one 1226 // (but allow split bundles) 1227 if( Pipeline::requires_bundling() && starts_bundle(n) ) 1228 cb->flush_bundle(false); 1229 1230 // The following logic is duplicated in the code ifdeffed for 1231 // ENABLE_ZAP_DEAD_LOCALS which appears above in this file. It 1232 // should be factored out. Or maybe dispersed to the nodes? 1233 1234 // Special handling for SafePoint/Call Nodes 1235 bool is_mcall = false; 1236 if( n->is_Mach() ) { 1237 MachNode *mach = n->as_Mach(); 1238 is_mcall = n->is_MachCall(); 1239 bool is_sfn = n->is_MachSafePoint(); 1240 1241 // If this requires all previous instructions be flushed, then do so 1242 if( is_sfn || is_mcall || mach->alignment_required() != 1) { 1243 cb->flush_bundle(true); 1244 current_offset = cb->insts_size(); 1245 } 1246 1247 // align the instruction if necessary 1248 int padding = mach->compute_padding(current_offset); 1249 // Make sure safepoint node for polling is distinct from a call's 1250 // return by adding a nop if needed. 1251 if (is_sfn && !is_mcall && padding == 0 && current_offset == last_call_offset ) { 1252 padding = nop_size; 1253 } 1254 assert( labels_not_set || padding == 0, "instruction should already be aligned"); 1255 1256 if(padding > 0) { 1257 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size"); 1258 int nops_cnt = padding / nop_size; 1259 MachNode *nop = new (this) MachNopNode(nops_cnt); 1260 b->_nodes.insert(j++, nop); 1261 last_inst++; 1262 _cfg->_bbs.map( nop->_idx, b ); 1263 nop->emit(*cb, _regalloc); 1264 cb->flush_bundle(true); 1265 current_offset = cb->insts_size(); 1266 } 1267 1268 // Remember the start of the last call in a basic block 1269 if (is_mcall) { 1270 MachCallNode *mcall = mach->as_MachCall(); 1271 1272 // This destination address is NOT PC-relative 1273 mcall->method_set((intptr_t)mcall->entry_point()); 1274 1275 // Save the return address 1276 call_returns[b->_pre_order] = current_offset + mcall->ret_addr_offset(); 1277 1278 if (!mcall->is_safepoint_node()) { 1279 is_mcall = false; 1280 is_sfn = false; 1281 } 1282 } 1283 1284 // sfn will be valid whenever mcall is valid now because of inheritance 1285 if( is_sfn || is_mcall ) { 1286 1287 // Handle special safepoint nodes for synchronization 1288 if( !is_mcall ) { 1289 MachSafePointNode *sfn = mach->as_MachSafePoint(); 1290 // !!!!! Stubs only need an oopmap right now, so bail out 1291 if( sfn->jvms()->method() == NULL) { 1292 // Write the oopmap directly to the code blob??!! 1293 # ifdef ENABLE_ZAP_DEAD_LOCALS 1294 assert( !is_node_getting_a_safepoint(sfn), "logic does not match; false positive"); 1295 # endif 1296 continue; 1297 } 1298 } // End synchronization 1299 1300 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(), 1301 current_offset); 1302 Process_OopMap_Node(mach, current_offset); 1303 } // End if safepoint 1304 1305 // If this is a null check, then add the start of the previous instruction to the list 1306 else if( mach->is_MachNullCheck() ) { 1307 inct_starts[inct_cnt++] = previous_offset; 1308 } 1309 1310 // If this is a branch, then fill in the label with the target BB's label 1311 else if ( mach->is_Branch() ) { 1312 1313 if ( mach->ideal_Opcode() == Op_Jump ) { 1314 for (uint h = 0; h < b->_num_succs; h++ ) { 1315 Block* succs_block = b->_succs[h]; 1316 for (uint j = 1; j < succs_block->num_preds(); j++) { 1317 Node* jpn = succs_block->pred(j); 1318 if ( jpn->is_JumpProj() && jpn->in(0) == mach ) { 1319 uint block_num = succs_block->non_connector()->_pre_order; 1320 Label *blkLabel = &blk_labels[block_num]; 1321 mach->add_case_label(jpn->as_JumpProj()->proj_no(), blkLabel); 1322 } 1323 } 1324 } 1325 } else { 1326 // For Branchs 1327 // This requires the TRUE branch target be in succs[0] 1328 uint block_num = b->non_connector_successor(0)->_pre_order; 1329 mach->label_set( blk_labels[block_num], block_num ); 1330 } 1331 } 1332 1333 #ifdef ASSERT 1334 // Check that oop-store precedes the card-mark 1335 else if( mach->ideal_Opcode() == Op_StoreCM ) { 1336 uint storeCM_idx = j; 1337 Node *oop_store = mach->in(mach->_cnt); // First precedence edge 1338 assert( oop_store != NULL, "storeCM expects a precedence edge"); 1339 uint i4; 1340 for( i4 = 0; i4 < last_inst; ++i4 ) { 1341 if( b->_nodes[i4] == oop_store ) break; 1342 } 1343 // Note: This test can provide a false failure if other precedence 1344 // edges have been added to the storeCMNode. 1345 assert( i4 == last_inst || i4 < storeCM_idx, "CM card-mark executes before oop-store"); 1346 } 1347 #endif 1348 1349 else if( !n->is_Proj() ) { 1350 // Remember the beginning of the previous instruction, in case 1351 // it's followed by a flag-kill and a null-check. Happens on 1352 // Intel all the time, with add-to-memory kind of opcodes. 1353 previous_offset = current_offset; 1354 } 1355 } 1356 1357 // Verify that there is sufficient space remaining 1358 cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size); 1359 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { 1360 turn_off_compiler(this); 1361 return; 1362 } 1363 1364 // Save the offset for the listing 1365 #ifndef PRODUCT 1366 if( node_offsets && n->_idx < node_offset_limit ) 1367 node_offsets[n->_idx] = cb->insts_size(); 1368 #endif 1369 1370 // "Normal" instruction case 1371 n->emit(*cb, _regalloc); 1372 current_offset = cb->insts_size(); 1373 non_safepoints.observe_instruction(n, current_offset); 1374 1375 // mcall is last "call" that can be a safepoint 1376 // record it so we can see if a poll will directly follow it 1377 // in which case we'll need a pad to make the PcDesc sites unique 1378 // see 5010568. This can be slightly inaccurate but conservative 1379 // in the case that return address is not actually at current_offset. 1380 // This is a small price to pay. 1381 1382 if (is_mcall) { 1383 last_call_offset = current_offset; 1384 } 1385 1386 // See if this instruction has a delay slot 1387 if ( valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) { 1388 assert(delay_slot != NULL, "expecting delay slot node"); 1389 1390 // Back up 1 instruction 1391 cb->set_insts_end(cb->insts_end() - Pipeline::instr_unit_size()); 1392 1393 // Save the offset for the listing 1394 #ifndef PRODUCT 1395 if( node_offsets && delay_slot->_idx < node_offset_limit ) 1396 node_offsets[delay_slot->_idx] = cb->insts_size(); 1397 #endif 1398 1399 // Support a SafePoint in the delay slot 1400 if( delay_slot->is_MachSafePoint() ) { 1401 MachNode *mach = delay_slot->as_Mach(); 1402 // !!!!! Stubs only need an oopmap right now, so bail out 1403 if( !mach->is_MachCall() && mach->as_MachSafePoint()->jvms()->method() == NULL ) { 1404 // Write the oopmap directly to the code blob??!! 1405 # ifdef ENABLE_ZAP_DEAD_LOCALS 1406 assert( !is_node_getting_a_safepoint(mach), "logic does not match; false positive"); 1407 # endif 1408 delay_slot = NULL; 1409 continue; 1410 } 1411 1412 int adjusted_offset = current_offset - Pipeline::instr_unit_size(); 1413 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(), 1414 adjusted_offset); 1415 // Generate an OopMap entry 1416 Process_OopMap_Node(mach, adjusted_offset); 1417 } 1418 1419 // Insert the delay slot instruction 1420 delay_slot->emit(*cb, _regalloc); 1421 1422 // Don't reuse it 1423 delay_slot = NULL; 1424 } 1425 1426 } // End for all instructions in block 1427 1428 // If the next block is the top of a loop, pad this block out to align 1429 // the loop top a little. Helps prevent pipe stalls at loop back branches. 1430 if( i<_cfg->_num_blocks-1 ) { 1431 Block *nb = _cfg->_blocks[i+1]; 1432 uint padding = nb->alignment_padding(current_offset); 1433 if( padding > 0 ) { 1434 MachNode *nop = new (this) MachNopNode(padding / nop_size); 1435 b->_nodes.insert( b->_nodes.size(), nop ); 1436 _cfg->_bbs.map( nop->_idx, b ); 1437 nop->emit(*cb, _regalloc); 1438 current_offset = cb->insts_size(); 1439 } 1440 } 1441 1442 } // End of for all blocks 1443 1444 non_safepoints.flush_at_end(); 1445 1446 // Offset too large? 1447 if (failing()) return; 1448 1449 // Define a pseudo-label at the end of the code 1450 MacroAssembler(cb).bind( blk_labels[_cfg->_num_blocks] ); 1451 1452 // Compute the size of the first block 1453 _first_block_size = blk_labels[1].loc_pos() - blk_labels[0].loc_pos(); 1454 1455 assert(cb->insts_size() < 500000, "method is unreasonably large"); 1456 1457 // ------------------ 1458 1459 #ifndef PRODUCT 1460 // Information on the size of the method, without the extraneous code 1461 Scheduling::increment_method_size(cb->insts_size()); 1462 #endif 1463 1464 // ------------------ 1465 // Fill in exception table entries. 1466 FillExceptionTables(inct_cnt, call_returns, inct_starts, blk_labels); 1467 1468 // Only java methods have exception handlers and deopt handlers 1469 if (_method) { 1470 // Emit the exception handler code. 1471 _code_offsets.set_value(CodeOffsets::Exceptions, emit_exception_handler(*cb)); 1472 // Emit the deopt handler code. 1473 _code_offsets.set_value(CodeOffsets::Deopt, emit_deopt_handler(*cb)); 1474 1475 // Emit the MethodHandle deopt handler code (if required). 1476 if (has_method_handle_invokes()) { 1477 // We can use the same code as for the normal deopt handler, we 1478 // just need a different entry point address. 1479 _code_offsets.set_value(CodeOffsets::DeoptMH, emit_deopt_handler(*cb)); 1480 } 1481 } 1482 1483 // One last check for failed CodeBuffer::expand: 1484 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { 1485 turn_off_compiler(this); 1486 return; 1487 } 1488 1489 #ifndef PRODUCT 1490 // Dump the assembly code, including basic-block numbers 1491 if (print_assembly()) { 1492 ttyLocker ttyl; // keep the following output all in one block 1493 if (!VMThread::should_terminate()) { // test this under the tty lock 1494 // This output goes directly to the tty, not the compiler log. 1495 // To enable tools to match it up with the compilation activity, 1496 // be sure to tag this tty output with the compile ID. 1497 if (xtty != NULL) { 1498 xtty->head("opto_assembly compile_id='%d'%s", compile_id(), 1499 is_osr_compilation() ? " compile_kind='osr'" : 1500 ""); 1501 } 1502 if (method() != NULL) { 1503 method()->print_oop(); 1504 print_codes(); 1505 } 1506 dump_asm(node_offsets, node_offset_limit); 1507 if (xtty != NULL) { 1508 xtty->tail("opto_assembly"); 1509 } 1510 } 1511 } 1512 #endif 1513 1514 } 1515 1516 void Compile::FillExceptionTables(uint cnt, uint *call_returns, uint *inct_starts, Label *blk_labels) { 1517 _inc_table.set_size(cnt); 1518 1519 uint inct_cnt = 0; 1520 for( uint i=0; i<_cfg->_num_blocks; i++ ) { 1521 Block *b = _cfg->_blocks[i]; 1522 Node *n = NULL; 1523 int j; 1524 1525 // Find the branch; ignore trailing NOPs. 1526 for( j = b->_nodes.size()-1; j>=0; j-- ) { 1527 n = b->_nodes[j]; 1528 if( !n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con ) 1529 break; 1530 } 1531 1532 // If we didn't find anything, continue 1533 if( j < 0 ) continue; 1534 1535 // Compute ExceptionHandlerTable subtable entry and add it 1536 // (skip empty blocks) 1537 if( n->is_Catch() ) { 1538 1539 // Get the offset of the return from the call 1540 uint call_return = call_returns[b->_pre_order]; 1541 #ifdef ASSERT 1542 assert( call_return > 0, "no call seen for this basic block" ); 1543 while( b->_nodes[--j]->Opcode() == Op_MachProj ) ; 1544 assert( b->_nodes[j]->is_Call(), "CatchProj must follow call" ); 1545 #endif 1546 // last instruction is a CatchNode, find it's CatchProjNodes 1547 int nof_succs = b->_num_succs; 1548 // allocate space 1549 GrowableArray<intptr_t> handler_bcis(nof_succs); 1550 GrowableArray<intptr_t> handler_pcos(nof_succs); 1551 // iterate through all successors 1552 for (int j = 0; j < nof_succs; j++) { 1553 Block* s = b->_succs[j]; 1554 bool found_p = false; 1555 for( uint k = 1; k < s->num_preds(); k++ ) { 1556 Node *pk = s->pred(k); 1557 if( pk->is_CatchProj() && pk->in(0) == n ) { 1558 const CatchProjNode* p = pk->as_CatchProj(); 1559 found_p = true; 1560 // add the corresponding handler bci & pco information 1561 if( p->_con != CatchProjNode::fall_through_index ) { 1562 // p leads to an exception handler (and is not fall through) 1563 assert(s == _cfg->_blocks[s->_pre_order],"bad numbering"); 1564 // no duplicates, please 1565 if( !handler_bcis.contains(p->handler_bci()) ) { 1566 uint block_num = s->non_connector()->_pre_order; 1567 handler_bcis.append(p->handler_bci()); 1568 handler_pcos.append(blk_labels[block_num].loc_pos()); 1569 } 1570 } 1571 } 1572 } 1573 assert(found_p, "no matching predecessor found"); 1574 // Note: Due to empty block removal, one block may have 1575 // several CatchProj inputs, from the same Catch. 1576 } 1577 1578 // Set the offset of the return from the call 1579 _handler_table.add_subtable(call_return, &handler_bcis, NULL, &handler_pcos); 1580 continue; 1581 } 1582 1583 // Handle implicit null exception table updates 1584 if( n->is_MachNullCheck() ) { 1585 uint block_num = b->non_connector_successor(0)->_pre_order; 1586 _inc_table.append( inct_starts[inct_cnt++], blk_labels[block_num].loc_pos() ); 1587 continue; 1588 } 1589 } // End of for all blocks fill in exception table entries 1590 } 1591 1592 // Static Variables 1593 #ifndef PRODUCT 1594 uint Scheduling::_total_nop_size = 0; 1595 uint Scheduling::_total_method_size = 0; 1596 uint Scheduling::_total_branches = 0; 1597 uint Scheduling::_total_unconditional_delays = 0; 1598 uint Scheduling::_total_instructions_per_bundle[Pipeline::_max_instrs_per_cycle+1]; 1599 #endif 1600 1601 // Initializer for class Scheduling 1602 1603 Scheduling::Scheduling(Arena *arena, Compile &compile) 1604 : _arena(arena), 1605 _cfg(compile.cfg()), 1606 _bbs(compile.cfg()->_bbs), 1607 _regalloc(compile.regalloc()), 1608 _reg_node(arena), 1609 _bundle_instr_count(0), 1610 _bundle_cycle_number(0), 1611 _scheduled(arena), 1612 _available(arena), 1613 _next_node(NULL), 1614 _bundle_use(0, 0, resource_count, &_bundle_use_elements[0]), 1615 _pinch_free_list(arena) 1616 #ifndef PRODUCT 1617 , _branches(0) 1618 , _unconditional_delays(0) 1619 #endif 1620 { 1621 // Create a MachNopNode 1622 _nop = new (&compile) MachNopNode(); 1623 1624 // Now that the nops are in the array, save the count 1625 // (but allow entries for the nops) 1626 _node_bundling_limit = compile.unique(); 1627 uint node_max = _regalloc->node_regs_max_index(); 1628 1629 compile.set_node_bundling_limit(_node_bundling_limit); 1630 1631 // This one is persistent within the Compile class 1632 _node_bundling_base = NEW_ARENA_ARRAY(compile.comp_arena(), Bundle, node_max); 1633 1634 // Allocate space for fixed-size arrays 1635 _node_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max); 1636 _uses = NEW_ARENA_ARRAY(arena, short, node_max); 1637 _current_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max); 1638 1639 // Clear the arrays 1640 memset(_node_bundling_base, 0, node_max * sizeof(Bundle)); 1641 memset(_node_latency, 0, node_max * sizeof(unsigned short)); 1642 memset(_uses, 0, node_max * sizeof(short)); 1643 memset(_current_latency, 0, node_max * sizeof(unsigned short)); 1644 1645 // Clear the bundling information 1646 memcpy(_bundle_use_elements, 1647 Pipeline_Use::elaborated_elements, 1648 sizeof(Pipeline_Use::elaborated_elements)); 1649 1650 // Get the last node 1651 Block *bb = _cfg->_blocks[_cfg->_blocks.size()-1]; 1652 1653 _next_node = bb->_nodes[bb->_nodes.size()-1]; 1654 } 1655 1656 #ifndef PRODUCT 1657 // Scheduling destructor 1658 Scheduling::~Scheduling() { 1659 _total_branches += _branches; 1660 _total_unconditional_delays += _unconditional_delays; 1661 } 1662 #endif 1663 1664 // Step ahead "i" cycles 1665 void Scheduling::step(uint i) { 1666 1667 Bundle *bundle = node_bundling(_next_node); 1668 bundle->set_starts_bundle(); 1669 1670 // Update the bundle record, but leave the flags information alone 1671 if (_bundle_instr_count > 0) { 1672 bundle->set_instr_count(_bundle_instr_count); 1673 bundle->set_resources_used(_bundle_use.resourcesUsed()); 1674 } 1675 1676 // Update the state information 1677 _bundle_instr_count = 0; 1678 _bundle_cycle_number += i; 1679 _bundle_use.step(i); 1680 } 1681 1682 void Scheduling::step_and_clear() { 1683 Bundle *bundle = node_bundling(_next_node); 1684 bundle->set_starts_bundle(); 1685 1686 // Update the bundle record 1687 if (_bundle_instr_count > 0) { 1688 bundle->set_instr_count(_bundle_instr_count); 1689 bundle->set_resources_used(_bundle_use.resourcesUsed()); 1690 1691 _bundle_cycle_number += 1; 1692 } 1693 1694 // Clear the bundling information 1695 _bundle_instr_count = 0; 1696 _bundle_use.reset(); 1697 1698 memcpy(_bundle_use_elements, 1699 Pipeline_Use::elaborated_elements, 1700 sizeof(Pipeline_Use::elaborated_elements)); 1701 } 1702 1703 //------------------------------ScheduleAndBundle------------------------------ 1704 // Perform instruction scheduling and bundling over the sequence of 1705 // instructions in backwards order. 1706 void Compile::ScheduleAndBundle() { 1707 1708 // Don't optimize this if it isn't a method 1709 if (!_method) 1710 return; 1711 1712 // Don't optimize this if scheduling is disabled 1713 if (!do_scheduling()) 1714 return; 1715 1716 NOT_PRODUCT( TracePhase t2("isched", &_t_instrSched, TimeCompiler); ) 1717 1718 // Create a data structure for all the scheduling information 1719 Scheduling scheduling(Thread::current()->resource_area(), *this); 1720 1721 // Walk backwards over each basic block, computing the needed alignment 1722 // Walk over all the basic blocks 1723 scheduling.DoScheduling(); 1724 } 1725 1726 //------------------------------ComputeLocalLatenciesForward------------------- 1727 // Compute the latency of all the instructions. This is fairly simple, 1728 // because we already have a legal ordering. Walk over the instructions 1729 // from first to last, and compute the latency of the instruction based 1730 // on the latency of the preceding instruction(s). 1731 void Scheduling::ComputeLocalLatenciesForward(const Block *bb) { 1732 #ifndef PRODUCT 1733 if (_cfg->C->trace_opto_output()) 1734 tty->print("# -> ComputeLocalLatenciesForward\n"); 1735 #endif 1736 1737 // Walk over all the schedulable instructions 1738 for( uint j=_bb_start; j < _bb_end; j++ ) { 1739 1740 // This is a kludge, forcing all latency calculations to start at 1. 1741 // Used to allow latency 0 to force an instruction to the beginning 1742 // of the bb 1743 uint latency = 1; 1744 Node *use = bb->_nodes[j]; 1745 uint nlen = use->len(); 1746 1747 // Walk over all the inputs 1748 for ( uint k=0; k < nlen; k++ ) { 1749 Node *def = use->in(k); 1750 if (!def) 1751 continue; 1752 1753 uint l = _node_latency[def->_idx] + use->latency(k); 1754 if (latency < l) 1755 latency = l; 1756 } 1757 1758 _node_latency[use->_idx] = latency; 1759 1760 #ifndef PRODUCT 1761 if (_cfg->C->trace_opto_output()) { 1762 tty->print("# latency %4d: ", latency); 1763 use->dump(); 1764 } 1765 #endif 1766 } 1767 1768 #ifndef PRODUCT 1769 if (_cfg->C->trace_opto_output()) 1770 tty->print("# <- ComputeLocalLatenciesForward\n"); 1771 #endif 1772 1773 } // end ComputeLocalLatenciesForward 1774 1775 // See if this node fits into the present instruction bundle 1776 bool Scheduling::NodeFitsInBundle(Node *n) { 1777 uint n_idx = n->_idx; 1778 1779 // If this is the unconditional delay instruction, then it fits 1780 if (n == _unconditional_delay_slot) { 1781 #ifndef PRODUCT 1782 if (_cfg->C->trace_opto_output()) 1783 tty->print("# NodeFitsInBundle [%4d]: TRUE; is in unconditional delay slot\n", n->_idx); 1784 #endif 1785 return (true); 1786 } 1787 1788 // If the node cannot be scheduled this cycle, skip it 1789 if (_current_latency[n_idx] > _bundle_cycle_number) { 1790 #ifndef PRODUCT 1791 if (_cfg->C->trace_opto_output()) 1792 tty->print("# NodeFitsInBundle [%4d]: FALSE; latency %4d > %d\n", 1793 n->_idx, _current_latency[n_idx], _bundle_cycle_number); 1794 #endif 1795 return (false); 1796 } 1797 1798 const Pipeline *node_pipeline = n->pipeline(); 1799 1800 uint instruction_count = node_pipeline->instructionCount(); 1801 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0) 1802 instruction_count = 0; 1803 else if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot) 1804 instruction_count++; 1805 1806 if (_bundle_instr_count + instruction_count > Pipeline::_max_instrs_per_cycle) { 1807 #ifndef PRODUCT 1808 if (_cfg->C->trace_opto_output()) 1809 tty->print("# NodeFitsInBundle [%4d]: FALSE; too many instructions: %d > %d\n", 1810 n->_idx, _bundle_instr_count + instruction_count, Pipeline::_max_instrs_per_cycle); 1811 #endif 1812 return (false); 1813 } 1814 1815 // Don't allow non-machine nodes to be handled this way 1816 if (!n->is_Mach() && instruction_count == 0) 1817 return (false); 1818 1819 // See if there is any overlap 1820 uint delay = _bundle_use.full_latency(0, node_pipeline->resourceUse()); 1821 1822 if (delay > 0) { 1823 #ifndef PRODUCT 1824 if (_cfg->C->trace_opto_output()) 1825 tty->print("# NodeFitsInBundle [%4d]: FALSE; functional units overlap\n", n_idx); 1826 #endif 1827 return false; 1828 } 1829 1830 #ifndef PRODUCT 1831 if (_cfg->C->trace_opto_output()) 1832 tty->print("# NodeFitsInBundle [%4d]: TRUE\n", n_idx); 1833 #endif 1834 1835 return true; 1836 } 1837 1838 Node * Scheduling::ChooseNodeToBundle() { 1839 uint siz = _available.size(); 1840 1841 if (siz == 0) { 1842 1843 #ifndef PRODUCT 1844 if (_cfg->C->trace_opto_output()) 1845 tty->print("# ChooseNodeToBundle: NULL\n"); 1846 #endif 1847 return (NULL); 1848 } 1849 1850 // Fast path, if only 1 instruction in the bundle 1851 if (siz == 1) { 1852 #ifndef PRODUCT 1853 if (_cfg->C->trace_opto_output()) { 1854 tty->print("# ChooseNodeToBundle (only 1): "); 1855 _available[0]->dump(); 1856 } 1857 #endif 1858 return (_available[0]); 1859 } 1860 1861 // Don't bother, if the bundle is already full 1862 if (_bundle_instr_count < Pipeline::_max_instrs_per_cycle) { 1863 for ( uint i = 0; i < siz; i++ ) { 1864 Node *n = _available[i]; 1865 1866 // Skip projections, we'll handle them another way 1867 if (n->is_Proj()) 1868 continue; 1869 1870 // This presupposed that instructions are inserted into the 1871 // available list in a legality order; i.e. instructions that 1872 // must be inserted first are at the head of the list 1873 if (NodeFitsInBundle(n)) { 1874 #ifndef PRODUCT 1875 if (_cfg->C->trace_opto_output()) { 1876 tty->print("# ChooseNodeToBundle: "); 1877 n->dump(); 1878 } 1879 #endif 1880 return (n); 1881 } 1882 } 1883 } 1884 1885 // Nothing fits in this bundle, choose the highest priority 1886 #ifndef PRODUCT 1887 if (_cfg->C->trace_opto_output()) { 1888 tty->print("# ChooseNodeToBundle: "); 1889 _available[0]->dump(); 1890 } 1891 #endif 1892 1893 return _available[0]; 1894 } 1895 1896 //------------------------------AddNodeToAvailableList------------------------- 1897 void Scheduling::AddNodeToAvailableList(Node *n) { 1898 assert( !n->is_Proj(), "projections never directly made available" ); 1899 #ifndef PRODUCT 1900 if (_cfg->C->trace_opto_output()) { 1901 tty->print("# AddNodeToAvailableList: "); 1902 n->dump(); 1903 } 1904 #endif 1905 1906 int latency = _current_latency[n->_idx]; 1907 1908 // Insert in latency order (insertion sort) 1909 uint i; 1910 for ( i=0; i < _available.size(); i++ ) 1911 if (_current_latency[_available[i]->_idx] > latency) 1912 break; 1913 1914 // Special Check for compares following branches 1915 if( n->is_Mach() && _scheduled.size() > 0 ) { 1916 int op = n->as_Mach()->ideal_Opcode(); 1917 Node *last = _scheduled[0]; 1918 if( last->is_MachIf() && last->in(1) == n && 1919 ( op == Op_CmpI || 1920 op == Op_CmpU || 1921 op == Op_CmpP || 1922 op == Op_CmpF || 1923 op == Op_CmpD || 1924 op == Op_CmpL ) ) { 1925 1926 // Recalculate position, moving to front of same latency 1927 for ( i=0 ; i < _available.size(); i++ ) 1928 if (_current_latency[_available[i]->_idx] >= latency) 1929 break; 1930 } 1931 } 1932 1933 // Insert the node in the available list 1934 _available.insert(i, n); 1935 1936 #ifndef PRODUCT 1937 if (_cfg->C->trace_opto_output()) 1938 dump_available(); 1939 #endif 1940 } 1941 1942 //------------------------------DecrementUseCounts----------------------------- 1943 void Scheduling::DecrementUseCounts(Node *n, const Block *bb) { 1944 for ( uint i=0; i < n->len(); i++ ) { 1945 Node *def = n->in(i); 1946 if (!def) continue; 1947 if( def->is_Proj() ) // If this is a machine projection, then 1948 def = def->in(0); // propagate usage thru to the base instruction 1949 1950 if( _bbs[def->_idx] != bb ) // Ignore if not block-local 1951 continue; 1952 1953 // Compute the latency 1954 uint l = _bundle_cycle_number + n->latency(i); 1955 if (_current_latency[def->_idx] < l) 1956 _current_latency[def->_idx] = l; 1957 1958 // If this does not have uses then schedule it 1959 if ((--_uses[def->_idx]) == 0) 1960 AddNodeToAvailableList(def); 1961 } 1962 } 1963 1964 //------------------------------AddNodeToBundle-------------------------------- 1965 void Scheduling::AddNodeToBundle(Node *n, const Block *bb) { 1966 #ifndef PRODUCT 1967 if (_cfg->C->trace_opto_output()) { 1968 tty->print("# AddNodeToBundle: "); 1969 n->dump(); 1970 } 1971 #endif 1972 1973 // Remove this from the available list 1974 uint i; 1975 for (i = 0; i < _available.size(); i++) 1976 if (_available[i] == n) 1977 break; 1978 assert(i < _available.size(), "entry in _available list not found"); 1979 _available.remove(i); 1980 1981 // See if this fits in the current bundle 1982 const Pipeline *node_pipeline = n->pipeline(); 1983 const Pipeline_Use& node_usage = node_pipeline->resourceUse(); 1984 1985 // Check for instructions to be placed in the delay slot. We 1986 // do this before we actually schedule the current instruction, 1987 // because the delay slot follows the current instruction. 1988 if (Pipeline::_branch_has_delay_slot && 1989 node_pipeline->hasBranchDelay() && 1990 !_unconditional_delay_slot) { 1991 1992 uint siz = _available.size(); 1993 1994 // Conditional branches can support an instruction that 1995 // is unconditionally executed and not dependent by the 1996 // branch, OR a conditionally executed instruction if 1997 // the branch is taken. In practice, this means that 1998 // the first instruction at the branch target is 1999 // copied to the delay slot, and the branch goes to 2000 // the instruction after that at the branch target 2001 if ( n->is_Mach() && n->is_Branch() ) { 2002 2003 assert( !n->is_MachNullCheck(), "should not look for delay slot for Null Check" ); 2004 assert( !n->is_Catch(), "should not look for delay slot for Catch" ); 2005 2006 #ifndef PRODUCT 2007 _branches++; 2008 #endif 2009 2010 // At least 1 instruction is on the available list 2011 // that is not dependent on the branch 2012 for (uint i = 0; i < siz; i++) { 2013 Node *d = _available[i]; 2014 const Pipeline *avail_pipeline = d->pipeline(); 2015 2016 // Don't allow safepoints in the branch shadow, that will 2017 // cause a number of difficulties 2018 if ( avail_pipeline->instructionCount() == 1 && 2019 !avail_pipeline->hasMultipleBundles() && 2020 !avail_pipeline->hasBranchDelay() && 2021 Pipeline::instr_has_unit_size() && 2022 d->size(_regalloc) == Pipeline::instr_unit_size() && 2023 NodeFitsInBundle(d) && 2024 !node_bundling(d)->used_in_delay()) { 2025 2026 if (d->is_Mach() && !d->is_MachSafePoint()) { 2027 // A node that fits in the delay slot was found, so we need to 2028 // set the appropriate bits in the bundle pipeline information so 2029 // that it correctly indicates resource usage. Later, when we 2030 // attempt to add this instruction to the bundle, we will skip 2031 // setting the resource usage. 2032 _unconditional_delay_slot = d; 2033 node_bundling(n)->set_use_unconditional_delay(); 2034 node_bundling(d)->set_used_in_unconditional_delay(); 2035 _bundle_use.add_usage(avail_pipeline->resourceUse()); 2036 _current_latency[d->_idx] = _bundle_cycle_number; 2037 _next_node = d; 2038 ++_bundle_instr_count; 2039 #ifndef PRODUCT 2040 _unconditional_delays++; 2041 #endif 2042 break; 2043 } 2044 } 2045 } 2046 } 2047 2048 // No delay slot, add a nop to the usage 2049 if (!_unconditional_delay_slot) { 2050 // See if adding an instruction in the delay slot will overflow 2051 // the bundle. 2052 if (!NodeFitsInBundle(_nop)) { 2053 #ifndef PRODUCT 2054 if (_cfg->C->trace_opto_output()) 2055 tty->print("# *** STEP(1 instruction for delay slot) ***\n"); 2056 #endif 2057 step(1); 2058 } 2059 2060 _bundle_use.add_usage(_nop->pipeline()->resourceUse()); 2061 _next_node = _nop; 2062 ++_bundle_instr_count; 2063 } 2064 2065 // See if the instruction in the delay slot requires a 2066 // step of the bundles 2067 if (!NodeFitsInBundle(n)) { 2068 #ifndef PRODUCT 2069 if (_cfg->C->trace_opto_output()) 2070 tty->print("# *** STEP(branch won't fit) ***\n"); 2071 #endif 2072 // Update the state information 2073 _bundle_instr_count = 0; 2074 _bundle_cycle_number += 1; 2075 _bundle_use.step(1); 2076 } 2077 } 2078 2079 // Get the number of instructions 2080 uint instruction_count = node_pipeline->instructionCount(); 2081 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0) 2082 instruction_count = 0; 2083 2084 // Compute the latency information 2085 uint delay = 0; 2086 2087 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) { 2088 int relative_latency = _current_latency[n->_idx] - _bundle_cycle_number; 2089 if (relative_latency < 0) 2090 relative_latency = 0; 2091 2092 delay = _bundle_use.full_latency(relative_latency, node_usage); 2093 2094 // Does not fit in this bundle, start a new one 2095 if (delay > 0) { 2096 step(delay); 2097 2098 #ifndef PRODUCT 2099 if (_cfg->C->trace_opto_output()) 2100 tty->print("# *** STEP(%d) ***\n", delay); 2101 #endif 2102 } 2103 } 2104 2105 // If this was placed in the delay slot, ignore it 2106 if (n != _unconditional_delay_slot) { 2107 2108 if (delay == 0) { 2109 if (node_pipeline->hasMultipleBundles()) { 2110 #ifndef PRODUCT 2111 if (_cfg->C->trace_opto_output()) 2112 tty->print("# *** STEP(multiple instructions) ***\n"); 2113 #endif 2114 step(1); 2115 } 2116 2117 else if (instruction_count + _bundle_instr_count > Pipeline::_max_instrs_per_cycle) { 2118 #ifndef PRODUCT 2119 if (_cfg->C->trace_opto_output()) 2120 tty->print("# *** STEP(%d >= %d instructions) ***\n", 2121 instruction_count + _bundle_instr_count, 2122 Pipeline::_max_instrs_per_cycle); 2123 #endif 2124 step(1); 2125 } 2126 } 2127 2128 if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot) 2129 _bundle_instr_count++; 2130 2131 // Set the node's latency 2132 _current_latency[n->_idx] = _bundle_cycle_number; 2133 2134 // Now merge the functional unit information 2135 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) 2136 _bundle_use.add_usage(node_usage); 2137 2138 // Increment the number of instructions in this bundle 2139 _bundle_instr_count += instruction_count; 2140 2141 // Remember this node for later 2142 if (n->is_Mach()) 2143 _next_node = n; 2144 } 2145 2146 // It's possible to have a BoxLock in the graph and in the _bbs mapping but 2147 // not in the bb->_nodes array. This happens for debug-info-only BoxLocks. 2148 // 'Schedule' them (basically ignore in the schedule) but do not insert them 2149 // into the block. All other scheduled nodes get put in the schedule here. 2150 int op = n->Opcode(); 2151 if( (op == Op_Node && n->req() == 0) || // anti-dependence node OR 2152 (op != Op_Node && // Not an unused antidepedence node and 2153 // not an unallocated boxlock 2154 (OptoReg::is_valid(_regalloc->get_reg_first(n)) || op != Op_BoxLock)) ) { 2155 2156 // Push any trailing projections 2157 if( bb->_nodes[bb->_nodes.size()-1] != n ) { 2158 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2159 Node *foi = n->fast_out(i); 2160 if( foi->is_Proj() ) 2161 _scheduled.push(foi); 2162 } 2163 } 2164 2165 // Put the instruction in the schedule list 2166 _scheduled.push(n); 2167 } 2168 2169 #ifndef PRODUCT 2170 if (_cfg->C->trace_opto_output()) 2171 dump_available(); 2172 #endif 2173 2174 // Walk all the definitions, decrementing use counts, and 2175 // if a definition has a 0 use count, place it in the available list. 2176 DecrementUseCounts(n,bb); 2177 } 2178 2179 //------------------------------ComputeUseCount-------------------------------- 2180 // This method sets the use count within a basic block. We will ignore all 2181 // uses outside the current basic block. As we are doing a backwards walk, 2182 // any node we reach that has a use count of 0 may be scheduled. This also 2183 // avoids the problem of cyclic references from phi nodes, as long as phi 2184 // nodes are at the front of the basic block. This method also initializes 2185 // the available list to the set of instructions that have no uses within this 2186 // basic block. 2187 void Scheduling::ComputeUseCount(const Block *bb) { 2188 #ifndef PRODUCT 2189 if (_cfg->C->trace_opto_output()) 2190 tty->print("# -> ComputeUseCount\n"); 2191 #endif 2192 2193 // Clear the list of available and scheduled instructions, just in case 2194 _available.clear(); 2195 _scheduled.clear(); 2196 2197 // No delay slot specified 2198 _unconditional_delay_slot = NULL; 2199 2200 #ifdef ASSERT 2201 for( uint i=0; i < bb->_nodes.size(); i++ ) 2202 assert( _uses[bb->_nodes[i]->_idx] == 0, "_use array not clean" ); 2203 #endif 2204 2205 // Force the _uses count to never go to zero for unscheduable pieces 2206 // of the block 2207 for( uint k = 0; k < _bb_start; k++ ) 2208 _uses[bb->_nodes[k]->_idx] = 1; 2209 for( uint l = _bb_end; l < bb->_nodes.size(); l++ ) 2210 _uses[bb->_nodes[l]->_idx] = 1; 2211 2212 // Iterate backwards over the instructions in the block. Don't count the 2213 // branch projections at end or the block header instructions. 2214 for( uint j = _bb_end-1; j >= _bb_start; j-- ) { 2215 Node *n = bb->_nodes[j]; 2216 if( n->is_Proj() ) continue; // Projections handled another way 2217 2218 // Account for all uses 2219 for ( uint k = 0; k < n->len(); k++ ) { 2220 Node *inp = n->in(k); 2221 if (!inp) continue; 2222 assert(inp != n, "no cycles allowed" ); 2223 if( _bbs[inp->_idx] == bb ) { // Block-local use? 2224 if( inp->is_Proj() ) // Skip through Proj's 2225 inp = inp->in(0); 2226 ++_uses[inp->_idx]; // Count 1 block-local use 2227 } 2228 } 2229 2230 // If this instruction has a 0 use count, then it is available 2231 if (!_uses[n->_idx]) { 2232 _current_latency[n->_idx] = _bundle_cycle_number; 2233 AddNodeToAvailableList(n); 2234 } 2235 2236 #ifndef PRODUCT 2237 if (_cfg->C->trace_opto_output()) { 2238 tty->print("# uses: %3d: ", _uses[n->_idx]); 2239 n->dump(); 2240 } 2241 #endif 2242 } 2243 2244 #ifndef PRODUCT 2245 if (_cfg->C->trace_opto_output()) 2246 tty->print("# <- ComputeUseCount\n"); 2247 #endif 2248 } 2249 2250 // This routine performs scheduling on each basic block in reverse order, 2251 // using instruction latencies and taking into account function unit 2252 // availability. 2253 void Scheduling::DoScheduling() { 2254 #ifndef PRODUCT 2255 if (_cfg->C->trace_opto_output()) 2256 tty->print("# -> DoScheduling\n"); 2257 #endif 2258 2259 Block *succ_bb = NULL; 2260 Block *bb; 2261 2262 // Walk over all the basic blocks in reverse order 2263 for( int i=_cfg->_num_blocks-1; i >= 0; succ_bb = bb, i-- ) { 2264 bb = _cfg->_blocks[i]; 2265 2266 #ifndef PRODUCT 2267 if (_cfg->C->trace_opto_output()) { 2268 tty->print("# Schedule BB#%03d (initial)\n", i); 2269 for (uint j = 0; j < bb->_nodes.size(); j++) 2270 bb->_nodes[j]->dump(); 2271 } 2272 #endif 2273 2274 // On the head node, skip processing 2275 if( bb == _cfg->_broot ) 2276 continue; 2277 2278 // Skip empty, connector blocks 2279 if (bb->is_connector()) 2280 continue; 2281 2282 // If the following block is not the sole successor of 2283 // this one, then reset the pipeline information 2284 if (bb->_num_succs != 1 || bb->non_connector_successor(0) != succ_bb) { 2285 #ifndef PRODUCT 2286 if (_cfg->C->trace_opto_output()) { 2287 tty->print("*** bundle start of next BB, node %d, for %d instructions\n", 2288 _next_node->_idx, _bundle_instr_count); 2289 } 2290 #endif 2291 step_and_clear(); 2292 } 2293 2294 // Leave untouched the starting instruction, any Phis, a CreateEx node 2295 // or Top. bb->_nodes[_bb_start] is the first schedulable instruction. 2296 _bb_end = bb->_nodes.size()-1; 2297 for( _bb_start=1; _bb_start <= _bb_end; _bb_start++ ) { 2298 Node *n = bb->_nodes[_bb_start]; 2299 // Things not matched, like Phinodes and ProjNodes don't get scheduled. 2300 // Also, MachIdealNodes do not get scheduled 2301 if( !n->is_Mach() ) continue; // Skip non-machine nodes 2302 MachNode *mach = n->as_Mach(); 2303 int iop = mach->ideal_Opcode(); 2304 if( iop == Op_CreateEx ) continue; // CreateEx is pinned 2305 if( iop == Op_Con ) continue; // Do not schedule Top 2306 if( iop == Op_Node && // Do not schedule PhiNodes, ProjNodes 2307 mach->pipeline() == MachNode::pipeline_class() && 2308 !n->is_SpillCopy() ) // Breakpoints, Prolog, etc 2309 continue; 2310 break; // Funny loop structure to be sure... 2311 } 2312 // Compute last "interesting" instruction in block - last instruction we 2313 // might schedule. _bb_end points just after last schedulable inst. We 2314 // normally schedule conditional branches (despite them being forced last 2315 // in the block), because they have delay slots we can fill. Calls all 2316 // have their delay slots filled in the template expansions, so we don't 2317 // bother scheduling them. 2318 Node *last = bb->_nodes[_bb_end]; 2319 if( last->is_Catch() || 2320 // Exclude unreachable path case when Halt node is in a separate block. 2321 (_bb_end > 1 && last->is_Mach() && last->as_Mach()->ideal_Opcode() == Op_Halt) ) { 2322 // There must be a prior call. Skip it. 2323 while( !bb->_nodes[--_bb_end]->is_Call() ) { 2324 assert( bb->_nodes[_bb_end]->is_Proj(), "skipping projections after expected call" ); 2325 } 2326 } else if( last->is_MachNullCheck() ) { 2327 // Backup so the last null-checked memory instruction is 2328 // outside the schedulable range. Skip over the nullcheck, 2329 // projection, and the memory nodes. 2330 Node *mem = last->in(1); 2331 do { 2332 _bb_end--; 2333 } while (mem != bb->_nodes[_bb_end]); 2334 } else { 2335 // Set _bb_end to point after last schedulable inst. 2336 _bb_end++; 2337 } 2338 2339 assert( _bb_start <= _bb_end, "inverted block ends" ); 2340 2341 // Compute the register antidependencies for the basic block 2342 ComputeRegisterAntidependencies(bb); 2343 if (_cfg->C->failing()) return; // too many D-U pinch points 2344 2345 // Compute intra-bb latencies for the nodes 2346 ComputeLocalLatenciesForward(bb); 2347 2348 // Compute the usage within the block, and set the list of all nodes 2349 // in the block that have no uses within the block. 2350 ComputeUseCount(bb); 2351 2352 // Schedule the remaining instructions in the block 2353 while ( _available.size() > 0 ) { 2354 Node *n = ChooseNodeToBundle(); 2355 AddNodeToBundle(n,bb); 2356 } 2357 2358 assert( _scheduled.size() == _bb_end - _bb_start, "wrong number of instructions" ); 2359 #ifdef ASSERT 2360 for( uint l = _bb_start; l < _bb_end; l++ ) { 2361 Node *n = bb->_nodes[l]; 2362 uint m; 2363 for( m = 0; m < _bb_end-_bb_start; m++ ) 2364 if( _scheduled[m] == n ) 2365 break; 2366 assert( m < _bb_end-_bb_start, "instruction missing in schedule" ); 2367 } 2368 #endif 2369 2370 // Now copy the instructions (in reverse order) back to the block 2371 for ( uint k = _bb_start; k < _bb_end; k++ ) 2372 bb->_nodes.map(k, _scheduled[_bb_end-k-1]); 2373 2374 #ifndef PRODUCT 2375 if (_cfg->C->trace_opto_output()) { 2376 tty->print("# Schedule BB#%03d (final)\n", i); 2377 uint current = 0; 2378 for (uint j = 0; j < bb->_nodes.size(); j++) { 2379 Node *n = bb->_nodes[j]; 2380 if( valid_bundle_info(n) ) { 2381 Bundle *bundle = node_bundling(n); 2382 if (bundle->instr_count() > 0 || bundle->flags() > 0) { 2383 tty->print("*** Bundle: "); 2384 bundle->dump(); 2385 } 2386 n->dump(); 2387 } 2388 } 2389 } 2390 #endif 2391 #ifdef ASSERT 2392 verify_good_schedule(bb,"after block local scheduling"); 2393 #endif 2394 } 2395 2396 #ifndef PRODUCT 2397 if (_cfg->C->trace_opto_output()) 2398 tty->print("# <- DoScheduling\n"); 2399 #endif 2400 2401 // Record final node-bundling array location 2402 _regalloc->C->set_node_bundling_base(_node_bundling_base); 2403 2404 } // end DoScheduling 2405 2406 //------------------------------verify_good_schedule--------------------------- 2407 // Verify that no live-range used in the block is killed in the block by a 2408 // wrong DEF. This doesn't verify live-ranges that span blocks. 2409 2410 // Check for edge existence. Used to avoid adding redundant precedence edges. 2411 static bool edge_from_to( Node *from, Node *to ) { 2412 for( uint i=0; i<from->len(); i++ ) 2413 if( from->in(i) == to ) 2414 return true; 2415 return false; 2416 } 2417 2418 #ifdef ASSERT 2419 //------------------------------verify_do_def---------------------------------- 2420 void Scheduling::verify_do_def( Node *n, OptoReg::Name def, const char *msg ) { 2421 // Check for bad kills 2422 if( OptoReg::is_valid(def) ) { // Ignore stores & control flow 2423 Node *prior_use = _reg_node[def]; 2424 if( prior_use && !edge_from_to(prior_use,n) ) { 2425 tty->print("%s = ",OptoReg::as_VMReg(def)->name()); 2426 n->dump(); 2427 tty->print_cr("..."); 2428 prior_use->dump(); 2429 assert(edge_from_to(prior_use,n),msg); 2430 } 2431 _reg_node.map(def,NULL); // Kill live USEs 2432 } 2433 } 2434 2435 //------------------------------verify_good_schedule--------------------------- 2436 void Scheduling::verify_good_schedule( Block *b, const char *msg ) { 2437 2438 // Zap to something reasonable for the verify code 2439 _reg_node.clear(); 2440 2441 // Walk over the block backwards. Check to make sure each DEF doesn't 2442 // kill a live value (other than the one it's supposed to). Add each 2443 // USE to the live set. 2444 for( uint i = b->_nodes.size()-1; i >= _bb_start; i-- ) { 2445 Node *n = b->_nodes[i]; 2446 int n_op = n->Opcode(); 2447 if( n_op == Op_MachProj && n->ideal_reg() == MachProjNode::fat_proj ) { 2448 // Fat-proj kills a slew of registers 2449 RegMask rm = n->out_RegMask();// Make local copy 2450 while( rm.is_NotEmpty() ) { 2451 OptoReg::Name kill = rm.find_first_elem(); 2452 rm.Remove(kill); 2453 verify_do_def( n, kill, msg ); 2454 } 2455 } else if( n_op != Op_Node ) { // Avoid brand new antidependence nodes 2456 // Get DEF'd registers the normal way 2457 verify_do_def( n, _regalloc->get_reg_first(n), msg ); 2458 verify_do_def( n, _regalloc->get_reg_second(n), msg ); 2459 } 2460 2461 // Now make all USEs live 2462 for( uint i=1; i<n->req(); i++ ) { 2463 Node *def = n->in(i); 2464 assert(def != 0, "input edge required"); 2465 OptoReg::Name reg_lo = _regalloc->get_reg_first(def); 2466 OptoReg::Name reg_hi = _regalloc->get_reg_second(def); 2467 if( OptoReg::is_valid(reg_lo) ) { 2468 assert(!_reg_node[reg_lo] || edge_from_to(_reg_node[reg_lo],def), msg); 2469 _reg_node.map(reg_lo,n); 2470 } 2471 if( OptoReg::is_valid(reg_hi) ) { 2472 assert(!_reg_node[reg_hi] || edge_from_to(_reg_node[reg_hi],def), msg); 2473 _reg_node.map(reg_hi,n); 2474 } 2475 } 2476 2477 } 2478 2479 // Zap to something reasonable for the Antidependence code 2480 _reg_node.clear(); 2481 } 2482 #endif 2483 2484 // Conditionally add precedence edges. Avoid putting edges on Projs. 2485 static void add_prec_edge_from_to( Node *from, Node *to ) { 2486 if( from->is_Proj() ) { // Put precedence edge on Proj's input 2487 assert( from->req() == 1 && (from->len() == 1 || from->in(1)==0), "no precedence edges on projections" ); 2488 from = from->in(0); 2489 } 2490 if( from != to && // No cycles (for things like LD L0,[L0+4] ) 2491 !edge_from_to( from, to ) ) // Avoid duplicate edge 2492 from->add_prec(to); 2493 } 2494 2495 //------------------------------anti_do_def------------------------------------ 2496 void Scheduling::anti_do_def( Block *b, Node *def, OptoReg::Name def_reg, int is_def ) { 2497 if( !OptoReg::is_valid(def_reg) ) // Ignore stores & control flow 2498 return; 2499 2500 Node *pinch = _reg_node[def_reg]; // Get pinch point 2501 if( !pinch || _bbs[pinch->_idx] != b || // No pinch-point yet? 2502 is_def ) { // Check for a true def (not a kill) 2503 _reg_node.map(def_reg,def); // Record def/kill as the optimistic pinch-point 2504 return; 2505 } 2506 2507 Node *kill = def; // Rename 'def' to more descriptive 'kill' 2508 debug_only( def = (Node*)0xdeadbeef; ) 2509 2510 // After some number of kills there _may_ be a later def 2511 Node *later_def = NULL; 2512 2513 // Finding a kill requires a real pinch-point. 2514 // Check for not already having a pinch-point. 2515 // Pinch points are Op_Node's. 2516 if( pinch->Opcode() != Op_Node ) { // Or later-def/kill as pinch-point? 2517 later_def = pinch; // Must be def/kill as optimistic pinch-point 2518 if ( _pinch_free_list.size() > 0) { 2519 pinch = _pinch_free_list.pop(); 2520 } else { 2521 pinch = new (_cfg->C, 1) Node(1); // Pinch point to-be 2522 } 2523 if (pinch->_idx >= _regalloc->node_regs_max_index()) { 2524 _cfg->C->record_method_not_compilable("too many D-U pinch points"); 2525 return; 2526 } 2527 _bbs.map(pinch->_idx,b); // Pretend it's valid in this block (lazy init) 2528 _reg_node.map(def_reg,pinch); // Record pinch-point 2529 //_regalloc->set_bad(pinch->_idx); // Already initialized this way. 2530 if( later_def->outcnt() == 0 || later_def->ideal_reg() == MachProjNode::fat_proj ) { // Distinguish def from kill 2531 pinch->init_req(0, _cfg->C->top()); // set not NULL for the next call 2532 add_prec_edge_from_to(later_def,pinch); // Add edge from kill to pinch 2533 later_def = NULL; // and no later def 2534 } 2535 pinch->set_req(0,later_def); // Hook later def so we can find it 2536 } else { // Else have valid pinch point 2537 if( pinch->in(0) ) // If there is a later-def 2538 later_def = pinch->in(0); // Get it 2539 } 2540 2541 // Add output-dependence edge from later def to kill 2542 if( later_def ) // If there is some original def 2543 add_prec_edge_from_to(later_def,kill); // Add edge from def to kill 2544 2545 // See if current kill is also a use, and so is forced to be the pinch-point. 2546 if( pinch->Opcode() == Op_Node ) { 2547 Node *uses = kill->is_Proj() ? kill->in(0) : kill; 2548 for( uint i=1; i<uses->req(); i++ ) { 2549 if( _regalloc->get_reg_first(uses->in(i)) == def_reg || 2550 _regalloc->get_reg_second(uses->in(i)) == def_reg ) { 2551 // Yes, found a use/kill pinch-point 2552 pinch->set_req(0,NULL); // 2553 pinch->replace_by(kill); // Move anti-dep edges up 2554 pinch = kill; 2555 _reg_node.map(def_reg,pinch); 2556 return; 2557 } 2558 } 2559 } 2560 2561 // Add edge from kill to pinch-point 2562 add_prec_edge_from_to(kill,pinch); 2563 } 2564 2565 //------------------------------anti_do_use------------------------------------ 2566 void Scheduling::anti_do_use( Block *b, Node *use, OptoReg::Name use_reg ) { 2567 if( !OptoReg::is_valid(use_reg) ) // Ignore stores & control flow 2568 return; 2569 Node *pinch = _reg_node[use_reg]; // Get pinch point 2570 // Check for no later def_reg/kill in block 2571 if( pinch && _bbs[pinch->_idx] == b && 2572 // Use has to be block-local as well 2573 _bbs[use->_idx] == b ) { 2574 if( pinch->Opcode() == Op_Node && // Real pinch-point (not optimistic?) 2575 pinch->req() == 1 ) { // pinch not yet in block? 2576 pinch->del_req(0); // yank pointer to later-def, also set flag 2577 // Insert the pinch-point in the block just after the last use 2578 b->_nodes.insert(b->find_node(use)+1,pinch); 2579 _bb_end++; // Increase size scheduled region in block 2580 } 2581 2582 add_prec_edge_from_to(pinch,use); 2583 } 2584 } 2585 2586 //------------------------------ComputeRegisterAntidependences----------------- 2587 // We insert antidependences between the reads and following write of 2588 // allocated registers to prevent illegal code motion. Hopefully, the 2589 // number of added references should be fairly small, especially as we 2590 // are only adding references within the current basic block. 2591 void Scheduling::ComputeRegisterAntidependencies(Block *b) { 2592 2593 #ifdef ASSERT 2594 verify_good_schedule(b,"before block local scheduling"); 2595 #endif 2596 2597 // A valid schedule, for each register independently, is an endless cycle 2598 // of: a def, then some uses (connected to the def by true dependencies), 2599 // then some kills (defs with no uses), finally the cycle repeats with a new 2600 // def. The uses are allowed to float relative to each other, as are the 2601 // kills. No use is allowed to slide past a kill (or def). This requires 2602 // antidependencies between all uses of a single def and all kills that 2603 // follow, up to the next def. More edges are redundant, because later defs 2604 // & kills are already serialized with true or antidependencies. To keep 2605 // the edge count down, we add a 'pinch point' node if there's more than 2606 // one use or more than one kill/def. 2607 2608 // We add dependencies in one bottom-up pass. 2609 2610 // For each instruction we handle it's DEFs/KILLs, then it's USEs. 2611 2612 // For each DEF/KILL, we check to see if there's a prior DEF/KILL for this 2613 // register. If not, we record the DEF/KILL in _reg_node, the 2614 // register-to-def mapping. If there is a prior DEF/KILL, we insert a 2615 // "pinch point", a new Node that's in the graph but not in the block. 2616 // We put edges from the prior and current DEF/KILLs to the pinch point. 2617 // We put the pinch point in _reg_node. If there's already a pinch point 2618 // we merely add an edge from the current DEF/KILL to the pinch point. 2619 2620 // After doing the DEF/KILLs, we handle USEs. For each used register, we 2621 // put an edge from the pinch point to the USE. 2622 2623 // To be expedient, the _reg_node array is pre-allocated for the whole 2624 // compilation. _reg_node is lazily initialized; it either contains a NULL, 2625 // or a valid def/kill/pinch-point, or a leftover node from some prior 2626 // block. Leftover node from some prior block is treated like a NULL (no 2627 // prior def, so no anti-dependence needed). Valid def is distinguished by 2628 // it being in the current block. 2629 bool fat_proj_seen = false; 2630 uint last_safept = _bb_end-1; 2631 Node* end_node = (_bb_end-1 >= _bb_start) ? b->_nodes[last_safept] : NULL; 2632 Node* last_safept_node = end_node; 2633 for( uint i = _bb_end-1; i >= _bb_start; i-- ) { 2634 Node *n = b->_nodes[i]; 2635 int is_def = n->outcnt(); // def if some uses prior to adding precedence edges 2636 if( n->Opcode() == Op_MachProj && n->ideal_reg() == MachProjNode::fat_proj ) { 2637 // Fat-proj kills a slew of registers 2638 // This can add edges to 'n' and obscure whether or not it was a def, 2639 // hence the is_def flag. 2640 fat_proj_seen = true; 2641 RegMask rm = n->out_RegMask();// Make local copy 2642 while( rm.is_NotEmpty() ) { 2643 OptoReg::Name kill = rm.find_first_elem(); 2644 rm.Remove(kill); 2645 anti_do_def( b, n, kill, is_def ); 2646 } 2647 } else { 2648 // Get DEF'd registers the normal way 2649 anti_do_def( b, n, _regalloc->get_reg_first(n), is_def ); 2650 anti_do_def( b, n, _regalloc->get_reg_second(n), is_def ); 2651 } 2652 2653 // Check each register used by this instruction for a following DEF/KILL 2654 // that must occur afterward and requires an anti-dependence edge. 2655 for( uint j=0; j<n->req(); j++ ) { 2656 Node *def = n->in(j); 2657 if( def ) { 2658 assert( def->Opcode() != Op_MachProj || def->ideal_reg() != MachProjNode::fat_proj, "" ); 2659 anti_do_use( b, n, _regalloc->get_reg_first(def) ); 2660 anti_do_use( b, n, _regalloc->get_reg_second(def) ); 2661 } 2662 } 2663 // Do not allow defs of new derived values to float above GC 2664 // points unless the base is definitely available at the GC point. 2665 2666 Node *m = b->_nodes[i]; 2667 2668 // Add precedence edge from following safepoint to use of derived pointer 2669 if( last_safept_node != end_node && 2670 m != last_safept_node) { 2671 for (uint k = 1; k < m->req(); k++) { 2672 const Type *t = m->in(k)->bottom_type(); 2673 if( t->isa_oop_ptr() && 2674 t->is_ptr()->offset() != 0 ) { 2675 last_safept_node->add_prec( m ); 2676 break; 2677 } 2678 } 2679 } 2680 2681 if( n->jvms() ) { // Precedence edge from derived to safept 2682 // Check if last_safept_node was moved by pinch-point insertion in anti_do_use() 2683 if( b->_nodes[last_safept] != last_safept_node ) { 2684 last_safept = b->find_node(last_safept_node); 2685 } 2686 for( uint j=last_safept; j > i; j-- ) { 2687 Node *mach = b->_nodes[j]; 2688 if( mach->is_Mach() && mach->as_Mach()->ideal_Opcode() == Op_AddP ) 2689 mach->add_prec( n ); 2690 } 2691 last_safept = i; 2692 last_safept_node = m; 2693 } 2694 } 2695 2696 if (fat_proj_seen) { 2697 // Garbage collect pinch nodes that were not consumed. 2698 // They are usually created by a fat kill MachProj for a call. 2699 garbage_collect_pinch_nodes(); 2700 } 2701 } 2702 2703 //------------------------------garbage_collect_pinch_nodes------------------------------- 2704 2705 // Garbage collect pinch nodes for reuse by other blocks. 2706 // 2707 // The block scheduler's insertion of anti-dependence 2708 // edges creates many pinch nodes when the block contains 2709 // 2 or more Calls. A pinch node is used to prevent a 2710 // combinatorial explosion of edges. If a set of kills for a 2711 // register is anti-dependent on a set of uses (or defs), rather 2712 // than adding an edge in the graph between each pair of kill 2713 // and use (or def), a pinch is inserted between them: 2714 // 2715 // use1 use2 use3 2716 // \ | / 2717 // \ | / 2718 // pinch 2719 // / | \ 2720 // / | \ 2721 // kill1 kill2 kill3 2722 // 2723 // One pinch node is created per register killed when 2724 // the second call is encountered during a backwards pass 2725 // over the block. Most of these pinch nodes are never 2726 // wired into the graph because the register is never 2727 // used or def'ed in the block. 2728 // 2729 void Scheduling::garbage_collect_pinch_nodes() { 2730 #ifndef PRODUCT 2731 if (_cfg->C->trace_opto_output()) tty->print("Reclaimed pinch nodes:"); 2732 #endif 2733 int trace_cnt = 0; 2734 for (uint k = 0; k < _reg_node.Size(); k++) { 2735 Node* pinch = _reg_node[k]; 2736 if (pinch != NULL && pinch->Opcode() == Op_Node && 2737 // no predecence input edges 2738 (pinch->req() == pinch->len() || pinch->in(pinch->req()) == NULL) ) { 2739 cleanup_pinch(pinch); 2740 _pinch_free_list.push(pinch); 2741 _reg_node.map(k, NULL); 2742 #ifndef PRODUCT 2743 if (_cfg->C->trace_opto_output()) { 2744 trace_cnt++; 2745 if (trace_cnt > 40) { 2746 tty->print("\n"); 2747 trace_cnt = 0; 2748 } 2749 tty->print(" %d", pinch->_idx); 2750 } 2751 #endif 2752 } 2753 } 2754 #ifndef PRODUCT 2755 if (_cfg->C->trace_opto_output()) tty->print("\n"); 2756 #endif 2757 } 2758 2759 // Clean up a pinch node for reuse. 2760 void Scheduling::cleanup_pinch( Node *pinch ) { 2761 assert (pinch && pinch->Opcode() == Op_Node && pinch->req() == 1, "just checking"); 2762 2763 for (DUIterator_Last imin, i = pinch->last_outs(imin); i >= imin; ) { 2764 Node* use = pinch->last_out(i); 2765 uint uses_found = 0; 2766 for (uint j = use->req(); j < use->len(); j++) { 2767 if (use->in(j) == pinch) { 2768 use->rm_prec(j); 2769 uses_found++; 2770 } 2771 } 2772 assert(uses_found > 0, "must be a precedence edge"); 2773 i -= uses_found; // we deleted 1 or more copies of this edge 2774 } 2775 // May have a later_def entry 2776 pinch->set_req(0, NULL); 2777 } 2778 2779 //------------------------------print_statistics------------------------------- 2780 #ifndef PRODUCT 2781 2782 void Scheduling::dump_available() const { 2783 tty->print("#Availist "); 2784 for (uint i = 0; i < _available.size(); i++) 2785 tty->print(" N%d/l%d", _available[i]->_idx,_current_latency[_available[i]->_idx]); 2786 tty->cr(); 2787 } 2788 2789 // Print Scheduling Statistics 2790 void Scheduling::print_statistics() { 2791 // Print the size added by nops for bundling 2792 tty->print("Nops added %d bytes to total of %d bytes", 2793 _total_nop_size, _total_method_size); 2794 if (_total_method_size > 0) 2795 tty->print(", for %.2f%%", 2796 ((double)_total_nop_size) / ((double) _total_method_size) * 100.0); 2797 tty->print("\n"); 2798 2799 // Print the number of branch shadows filled 2800 if (Pipeline::_branch_has_delay_slot) { 2801 tty->print("Of %d branches, %d had unconditional delay slots filled", 2802 _total_branches, _total_unconditional_delays); 2803 if (_total_branches > 0) 2804 tty->print(", for %.2f%%", 2805 ((double)_total_unconditional_delays) / ((double)_total_branches) * 100.0); 2806 tty->print("\n"); 2807 } 2808 2809 uint total_instructions = 0, total_bundles = 0; 2810 2811 for (uint i = 1; i <= Pipeline::_max_instrs_per_cycle; i++) { 2812 uint bundle_count = _total_instructions_per_bundle[i]; 2813 total_instructions += bundle_count * i; 2814 total_bundles += bundle_count; 2815 } 2816 2817 if (total_bundles > 0) 2818 tty->print("Average ILP (excluding nops) is %.2f\n", 2819 ((double)total_instructions) / ((double)total_bundles)); 2820 } 2821 #endif