output.cpp revision 2614:95134e034042
1/* 2 * Copyright (c) 1998, 2011, 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 44extern uint size_java_to_interp(); 45extern uint reloc_java_to_interp(); 46extern uint size_exception_handler(); 47extern uint size_deopt_handler(); 48 49#ifndef PRODUCT 50#define DEBUG_ARG(x) , x 51#else 52#define DEBUG_ARG(x) 53#endif 54 55extern int emit_exception_handler(CodeBuffer &cbuf); 56extern int emit_deopt_handler(CodeBuffer &cbuf); 57 58//------------------------------Output----------------------------------------- 59// Convert Nodes to instruction bits and pass off to the VM 60void Compile::Output() { 61 // RootNode goes 62 assert( _cfg->_broot->_nodes.size() == 0, "" ); 63 64 // The number of new nodes (mostly MachNop) is proportional to 65 // the number of java calls and inner loops which are aligned. 66 if ( C->check_node_count((NodeLimitFudgeFactor + C->java_calls()*3 + 67 C->inner_loops()*(OptoLoopAlignment-1)), 68 "out of nodes before code generation" ) ) { 69 return; 70 } 71 // Make sure I can find the Start Node 72 Block_Array& bbs = _cfg->_bbs; 73 Block *entry = _cfg->_blocks[1]; 74 Block *broot = _cfg->_broot; 75 76 const StartNode *start = entry->_nodes[0]->as_Start(); 77 78 // Replace StartNode with prolog 79 MachPrologNode *prolog = new (this) MachPrologNode(); 80 entry->_nodes.map( 0, prolog ); 81 bbs.map( prolog->_idx, entry ); 82 bbs.map( start->_idx, NULL ); // start is no longer in any block 83 84 // Virtual methods need an unverified entry point 85 86 if( is_osr_compilation() ) { 87 if( PoisonOSREntry ) { 88 // TODO: Should use a ShouldNotReachHereNode... 89 _cfg->insert( broot, 0, new (this) MachBreakpointNode() ); 90 } 91 } else { 92 if( _method && !_method->flags().is_static() ) { 93 // Insert unvalidated entry point 94 _cfg->insert( broot, 0, new (this) MachUEPNode() ); 95 } 96 97 } 98 99 100 // Break before main entry point 101 if( (_method && _method->break_at_execute()) 102#ifndef PRODUCT 103 ||(OptoBreakpoint && is_method_compilation()) 104 ||(OptoBreakpointOSR && is_osr_compilation()) 105 ||(OptoBreakpointC2R && !_method) 106#endif 107 ) { 108 // checking for _method means that OptoBreakpoint does not apply to 109 // runtime stubs or frame converters 110 _cfg->insert( entry, 1, new (this) MachBreakpointNode() ); 111 } 112 113 // Insert epilogs before every return 114 for( uint i=0; i<_cfg->_num_blocks; i++ ) { 115 Block *b = _cfg->_blocks[i]; 116 if( !b->is_connector() && b->non_connector_successor(0) == _cfg->_broot ) { // Found a program exit point? 117 Node *m = b->end(); 118 if( m->is_Mach() && m->as_Mach()->ideal_Opcode() != Op_Halt ) { 119 MachEpilogNode *epilog = new (this) MachEpilogNode(m->as_Mach()->ideal_Opcode() == Op_Return); 120 b->add_inst( epilog ); 121 bbs.map(epilog->_idx, b); 122 //_regalloc->set_bad(epilog->_idx); // Already initialized this way. 123 } 124 } 125 } 126 127# ifdef ENABLE_ZAP_DEAD_LOCALS 128 if ( ZapDeadCompiledLocals ) Insert_zap_nodes(); 129# endif 130 131 uint* blk_starts = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks+1); 132 blk_starts[0] = 0; 133 134 // Initialize code buffer and process short branches. 135 CodeBuffer* cb = init_buffer(blk_starts); 136 137 if (cb == NULL || failing()) return; 138 139 ScheduleAndBundle(); 140 141#ifndef PRODUCT 142 if (trace_opto_output()) { 143 tty->print("\n---- After ScheduleAndBundle ----\n"); 144 for (uint i = 0; i < _cfg->_num_blocks; i++) { 145 tty->print("\nBB#%03d:\n", i); 146 Block *bb = _cfg->_blocks[i]; 147 for (uint j = 0; j < bb->_nodes.size(); j++) { 148 Node *n = bb->_nodes[j]; 149 OptoReg::Name reg = _regalloc->get_reg_first(n); 150 tty->print(" %-6s ", reg >= 0 && reg < REG_COUNT ? Matcher::regName[reg] : ""); 151 n->dump(); 152 } 153 } 154 } 155#endif 156 157 if (failing()) return; 158 159 finalize_offsets_and_shorten(blk_starts); 160 161 BuildOopMaps(); 162 163 if (failing()) return; 164 165 fill_buffer(cb, blk_starts); 166} 167 168bool Compile::need_stack_bang(int frame_size_in_bytes) const { 169 // Determine if we need to generate a stack overflow check. 170 // Do it if the method is not a stub function and 171 // has java calls or has frame size > vm_page_size/8. 172 return (stub_function() == NULL && 173 (has_java_calls() || frame_size_in_bytes > os::vm_page_size()>>3)); 174} 175 176bool Compile::need_register_stack_bang() const { 177 // Determine if we need to generate a register stack overflow check. 178 // This is only used on architectures which have split register 179 // and memory stacks (ie. IA64). 180 // Bang if the method is not a stub function and has java calls 181 return (stub_function() == NULL && has_java_calls()); 182} 183 184# ifdef ENABLE_ZAP_DEAD_LOCALS 185 186 187// In order to catch compiler oop-map bugs, we have implemented 188// a debugging mode called ZapDeadCompilerLocals. 189// This mode causes the compiler to insert a call to a runtime routine, 190// "zap_dead_locals", right before each place in compiled code 191// that could potentially be a gc-point (i.e., a safepoint or oop map point). 192// The runtime routine checks that locations mapped as oops are really 193// oops, that locations mapped as values do not look like oops, 194// and that locations mapped as dead are not used later 195// (by zapping them to an invalid address). 196 197int Compile::_CompiledZap_count = 0; 198 199void Compile::Insert_zap_nodes() { 200 bool skip = false; 201 202 203 // Dink with static counts because code code without the extra 204 // runtime calls is MUCH faster for debugging purposes 205 206 if ( CompileZapFirst == 0 ) ; // nothing special 207 else if ( CompileZapFirst > CompiledZap_count() ) skip = true; 208 else if ( CompileZapFirst == CompiledZap_count() ) 209 warning("starting zap compilation after skipping"); 210 211 if ( CompileZapLast == -1 ) ; // nothing special 212 else if ( CompileZapLast < CompiledZap_count() ) skip = true; 213 else if ( CompileZapLast == CompiledZap_count() ) 214 warning("about to compile last zap"); 215 216 ++_CompiledZap_count; // counts skipped zaps, too 217 218 if ( skip ) return; 219 220 221 if ( _method == NULL ) 222 return; // no safepoints/oopmaps emitted for calls in stubs,so we don't care 223 224 // Insert call to zap runtime stub before every node with an oop map 225 for( uint i=0; i<_cfg->_num_blocks; i++ ) { 226 Block *b = _cfg->_blocks[i]; 227 for ( uint j = 0; j < b->_nodes.size(); ++j ) { 228 Node *n = b->_nodes[j]; 229 230 // Determining if we should insert a zap-a-lot node in output. 231 // We do that for all nodes that has oopmap info, except for calls 232 // to allocation. Calls to allocation passes in the old top-of-eden pointer 233 // and expect the C code to reset it. Hence, there can be no safepoints between 234 // the inlined-allocation and the call to new_Java, etc. 235 // We also cannot zap monitor calls, as they must hold the microlock 236 // during the call to Zap, which also wants to grab the microlock. 237 bool insert = n->is_MachSafePoint() && (n->as_MachSafePoint()->oop_map() != NULL); 238 if ( insert ) { // it is MachSafePoint 239 if ( !n->is_MachCall() ) { 240 insert = false; 241 } else if ( n->is_MachCall() ) { 242 MachCallNode* call = n->as_MachCall(); 243 if (call->entry_point() == OptoRuntime::new_instance_Java() || 244 call->entry_point() == OptoRuntime::new_array_Java() || 245 call->entry_point() == OptoRuntime::multianewarray2_Java() || 246 call->entry_point() == OptoRuntime::multianewarray3_Java() || 247 call->entry_point() == OptoRuntime::multianewarray4_Java() || 248 call->entry_point() == OptoRuntime::multianewarray5_Java() || 249 call->entry_point() == OptoRuntime::slow_arraycopy_Java() || 250 call->entry_point() == OptoRuntime::complete_monitor_locking_Java() 251 ) { 252 insert = false; 253 } 254 } 255 if (insert) { 256 Node *zap = call_zap_node(n->as_MachSafePoint(), i); 257 b->_nodes.insert( j, zap ); 258 _cfg->_bbs.map( zap->_idx, b ); 259 ++j; 260 } 261 } 262 } 263 } 264} 265 266 267Node* Compile::call_zap_node(MachSafePointNode* node_to_check, int block_no) { 268 const TypeFunc *tf = OptoRuntime::zap_dead_locals_Type(); 269 CallStaticJavaNode* ideal_node = 270 new (this, tf->domain()->cnt()) CallStaticJavaNode( tf, 271 OptoRuntime::zap_dead_locals_stub(_method->flags().is_native()), 272 "call zap dead locals stub", 0, TypePtr::BOTTOM); 273 // We need to copy the OopMap from the site we're zapping at. 274 // We have to make a copy, because the zap site might not be 275 // a call site, and zap_dead is a call site. 276 OopMap* clone = node_to_check->oop_map()->deep_copy(); 277 278 // Add the cloned OopMap to the zap node 279 ideal_node->set_oop_map(clone); 280 return _matcher->match_sfpt(ideal_node); 281} 282 283//------------------------------is_node_getting_a_safepoint-------------------- 284bool Compile::is_node_getting_a_safepoint( Node* n) { 285 // This code duplicates the logic prior to the call of add_safepoint 286 // below in this file. 287 if( n->is_MachSafePoint() ) return true; 288 return false; 289} 290 291# endif // ENABLE_ZAP_DEAD_LOCALS 292 293//------------------------------compute_loop_first_inst_sizes------------------ 294// Compute the size of first NumberOfLoopInstrToAlign instructions at the top 295// of a loop. When aligning a loop we need to provide enough instructions 296// in cpu's fetch buffer to feed decoders. The loop alignment could be 297// avoided if we have enough instructions in fetch buffer at the head of a loop. 298// By default, the size is set to 999999 by Block's constructor so that 299// a loop will be aligned if the size is not reset here. 300// 301// Note: Mach instructions could contain several HW instructions 302// so the size is estimated only. 303// 304void Compile::compute_loop_first_inst_sizes() { 305 // The next condition is used to gate the loop alignment optimization. 306 // Don't aligned a loop if there are enough instructions at the head of a loop 307 // or alignment padding is larger then MaxLoopPad. By default, MaxLoopPad 308 // is equal to OptoLoopAlignment-1 except on new Intel cpus, where it is 309 // equal to 11 bytes which is the largest address NOP instruction. 310 if( MaxLoopPad < OptoLoopAlignment-1 ) { 311 uint last_block = _cfg->_num_blocks-1; 312 for( uint i=1; i <= last_block; i++ ) { 313 Block *b = _cfg->_blocks[i]; 314 // Check the first loop's block which requires an alignment. 315 if( b->loop_alignment() > (uint)relocInfo::addr_unit() ) { 316 uint sum_size = 0; 317 uint inst_cnt = NumberOfLoopInstrToAlign; 318 inst_cnt = b->compute_first_inst_size(sum_size, inst_cnt, _regalloc); 319 320 // Check subsequent fallthrough blocks if the loop's first 321 // block(s) does not have enough instructions. 322 Block *nb = b; 323 while( inst_cnt > 0 && 324 i < last_block && 325 !_cfg->_blocks[i+1]->has_loop_alignment() && 326 !nb->has_successor(b) ) { 327 i++; 328 nb = _cfg->_blocks[i]; 329 inst_cnt = nb->compute_first_inst_size(sum_size, inst_cnt, _regalloc); 330 } // while( inst_cnt > 0 && i < last_block ) 331 332 b->set_first_inst_size(sum_size); 333 } // f( b->head()->is_Loop() ) 334 } // for( i <= last_block ) 335 } // if( MaxLoopPad < OptoLoopAlignment-1 ) 336} 337 338//----------------------shorten_branches--------------------------------------- 339// The architecture description provides short branch variants for some long 340// branch instructions. Replace eligible long branches with short branches. 341void Compile::shorten_branches(uint* blk_starts, int& code_size, int& reloc_size, int& stub_size) { 342 343 // ------------------ 344 // Compute size of each block, method size, and relocation information size 345 uint nblocks = _cfg->_num_blocks; 346 347 uint* jmp_offset = NEW_RESOURCE_ARRAY(uint,nblocks); 348 uint* jmp_size = NEW_RESOURCE_ARRAY(uint,nblocks); 349 int* jmp_nidx = NEW_RESOURCE_ARRAY(int ,nblocks); 350 DEBUG_ONLY( uint *jmp_target = NEW_RESOURCE_ARRAY(uint,nblocks); ) 351 DEBUG_ONLY( uint *jmp_rule = NEW_RESOURCE_ARRAY(uint,nblocks); ) 352 353 bool has_short_branch_candidate = false; 354 355 // Initialize the sizes to 0 356 code_size = 0; // Size in bytes of generated code 357 stub_size = 0; // Size in bytes of all stub entries 358 // Size in bytes of all relocation entries, including those in local stubs. 359 // Start with 2-bytes of reloc info for the unvalidated entry point 360 reloc_size = 1; // Number of relocation entries 361 362 // Make three passes. The first computes pessimistic blk_starts, 363 // relative jmp_offset and reloc_size information. The second performs 364 // short branch substitution using the pessimistic sizing. The 365 // third inserts nops where needed. 366 367 // Step one, perform a pessimistic sizing pass. 368 uint last_call_adr = max_uint; 369 uint last_avoid_back_to_back_adr = max_uint; 370 uint nop_size = (new (this) MachNopNode())->size(_regalloc); 371 for (uint i = 0; i < nblocks; i++) { // For all blocks 372 Block *b = _cfg->_blocks[i]; 373 374 // During short branch replacement, we store the relative (to blk_starts) 375 // offset of jump in jmp_offset, rather than the absolute offset of jump. 376 // This is so that we do not need to recompute sizes of all nodes when 377 // we compute correct blk_starts in our next sizing pass. 378 jmp_offset[i] = 0; 379 jmp_size[i] = 0; 380 jmp_nidx[i] = -1; 381 DEBUG_ONLY( jmp_target[i] = 0; ) 382 DEBUG_ONLY( jmp_rule[i] = 0; ) 383 384 // Sum all instruction sizes to compute block size 385 uint last_inst = b->_nodes.size(); 386 uint blk_size = 0; 387 for (uint j = 0; j < last_inst; j++) { 388 Node* nj = b->_nodes[j]; 389 uint inst_size = nj->size(_regalloc); 390 // Handle machine instruction nodes 391 if (nj->is_Mach()) { 392 MachNode *mach = nj->as_Mach(); 393 blk_size += (mach->alignment_required() - 1) * relocInfo::addr_unit(); // assume worst case padding 394 reloc_size += mach->reloc(); 395 if( mach->is_MachCall() ) { 396 MachCallNode *mcall = mach->as_MachCall(); 397 // This destination address is NOT PC-relative 398 399 mcall->method_set((intptr_t)mcall->entry_point()); 400 401 if( mcall->is_MachCallJava() && mcall->as_MachCallJava()->_method ) { 402 stub_size += size_java_to_interp(); 403 reloc_size += reloc_java_to_interp(); 404 } 405 } else if (mach->is_MachSafePoint()) { 406 // If call/safepoint are adjacent, account for possible 407 // nop to disambiguate the two safepoints. 408 // ScheduleAndBundle() can rearrange nodes in a block, 409 // check for all offsets inside this block. 410 if (last_call_adr >= blk_starts[i]) { 411 blk_size += nop_size; 412 } 413 } 414 if (mach->avoid_back_to_back()) { 415 // Nop is inserted between "avoid back to back" instructions. 416 // ScheduleAndBundle() can rearrange nodes in a block, 417 // check for all offsets inside this block. 418 if (last_avoid_back_to_back_adr >= blk_starts[i]) { 419 blk_size += nop_size; 420 } 421 } 422 if (mach->may_be_short_branch()) { 423 if (!nj->is_Branch()) { 424#ifndef PRODUCT 425 nj->dump(3); 426#endif 427 Unimplemented(); 428 } 429 assert(jmp_nidx[i] == -1, "block should have only one branch"); 430 jmp_offset[i] = blk_size; 431 jmp_size[i] = inst_size; 432 jmp_nidx[i] = j; 433 has_short_branch_candidate = true; 434 } 435 } 436 blk_size += inst_size; 437 // Remember end of call offset 438 if (nj->is_MachCall() && !nj->is_MachCallLeaf()) { 439 last_call_adr = blk_starts[i]+blk_size; 440 } 441 // Remember end of avoid_back_to_back offset 442 if (nj->is_Mach() && nj->as_Mach()->avoid_back_to_back()) { 443 last_avoid_back_to_back_adr = blk_starts[i]+blk_size; 444 } 445 } 446 447 // When the next block starts a loop, we may insert pad NOP 448 // instructions. Since we cannot know our future alignment, 449 // assume the worst. 450 if (i< nblocks-1) { 451 Block *nb = _cfg->_blocks[i+1]; 452 int max_loop_pad = nb->code_alignment()-relocInfo::addr_unit(); 453 if (max_loop_pad > 0) { 454 assert(is_power_of_2(max_loop_pad+relocInfo::addr_unit()), ""); 455 blk_size += max_loop_pad; 456 } 457 } 458 459 // Save block size; update total method size 460 blk_starts[i+1] = blk_starts[i]+blk_size; 461 } 462 463 // Step two, replace eligible long jumps. 464 bool progress = true; 465 uint last_may_be_short_branch_adr = max_uint; 466 while (has_short_branch_candidate && progress) { 467 progress = false; 468 has_short_branch_candidate = false; 469 int adjust_block_start = 0; 470 for (uint i = 0; i < nblocks; i++) { 471 Block *b = _cfg->_blocks[i]; 472 int idx = jmp_nidx[i]; 473 MachNode* mach = (idx == -1) ? NULL: b->_nodes[idx]->as_Mach(); 474 if (mach != NULL && mach->may_be_short_branch()) { 475#ifdef ASSERT 476 assert(jmp_size[i] > 0 && mach->is_Branch(), "sanity"); 477 int j; 478 // Find the branch; ignore trailing NOPs. 479 for (j = b->_nodes.size()-1; j>=0; j--) { 480 Node* n = b->_nodes[j]; 481 if (!n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con) 482 break; 483 } 484 assert(j >= 0 && j == idx && b->_nodes[j] == (Node*)mach, "sanity"); 485#endif 486 int br_size = jmp_size[i]; 487 int br_offs = blk_starts[i] + jmp_offset[i]; 488 489 // This requires the TRUE branch target be in succs[0] 490 uint bnum = b->non_connector_successor(0)->_pre_order; 491 int offset = blk_starts[bnum] - br_offs; 492 if (bnum > i) { // adjust following block's offset 493 offset -= adjust_block_start; 494 } 495 // In the following code a nop could be inserted before 496 // the branch which will increase the backward distance. 497 bool needs_padding = ((uint)br_offs == last_may_be_short_branch_adr); 498 if (needs_padding && offset <= 0) 499 offset -= nop_size; 500 501 if (_matcher->is_short_branch_offset(mach->rule(), br_size, offset)) { 502 // We've got a winner. Replace this branch. 503 MachNode* replacement = mach->short_branch_version(this); 504 505 // Update the jmp_size. 506 int new_size = replacement->size(_regalloc); 507 int diff = br_size - new_size; 508 assert(diff >= (int)nop_size, "short_branch size should be smaller"); 509 // Conservatively take into accound padding between 510 // avoid_back_to_back branches. Previous branch could be 511 // converted into avoid_back_to_back branch during next 512 // rounds. 513 if (needs_padding && replacement->avoid_back_to_back()) { 514 jmp_offset[i] += nop_size; 515 diff -= nop_size; 516 } 517 adjust_block_start += diff; 518 b->_nodes.map(idx, replacement); 519 mach->subsume_by(replacement); 520 mach = replacement; 521 progress = true; 522 523 jmp_size[i] = new_size; 524 DEBUG_ONLY( jmp_target[i] = bnum; ); 525 DEBUG_ONLY( jmp_rule[i] = mach->rule(); ); 526 } else { 527 // The jump distance is not short, try again during next iteration. 528 has_short_branch_candidate = true; 529 } 530 } // (mach->may_be_short_branch()) 531 if (mach != NULL && (mach->may_be_short_branch() || 532 mach->avoid_back_to_back())) { 533 last_may_be_short_branch_adr = blk_starts[i] + jmp_offset[i] + jmp_size[i]; 534 } 535 blk_starts[i+1] -= adjust_block_start; 536 } 537 } 538 539#ifdef ASSERT 540 for (uint i = 0; i < nblocks; i++) { // For all blocks 541 if (jmp_target[i] != 0) { 542 int br_size = jmp_size[i]; 543 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_offset[i]); 544 if (!_matcher->is_short_branch_offset(jmp_rule[i], br_size, offset)) { 545 tty->print_cr("target (%d) - jmp_offset(%d) = offset (%d), jump_size(%d), jmp_block B%d, target_block B%d", blk_starts[jmp_target[i]], blk_starts[i] + jmp_offset[i], offset, br_size, i, jmp_target[i]); 546 } 547 assert(_matcher->is_short_branch_offset(jmp_rule[i], br_size, offset), "Displacement too large for short jmp"); 548 } 549 } 550#endif 551 552 // Step 3, compute the offsets of all blocks, will be done in finalize_offsets_and_shorten() 553 // after ScheduleAndBundle(). 554 555 // ------------------ 556 // Compute size for code buffer 557 code_size = blk_starts[nblocks]; 558 559 // Relocation records 560 reloc_size += 1; // Relo entry for exception handler 561 562 // Adjust reloc_size to number of record of relocation info 563 // Min is 2 bytes, max is probably 6 or 8, with a tax up to 25% for 564 // a relocation index. 565 // The CodeBuffer will expand the locs array if this estimate is too low. 566 reloc_size *= 10 / sizeof(relocInfo); 567} 568 569//----------------------finalize_offsets_and_shorten------------------------- 570void Compile::finalize_offsets_and_shorten(uint* blk_starts) { 571 // blk_starts[] contains offsets calculated during short branches processing, 572 // offsets should not be increased during following steps. 573 574 // Compute the size of first NumberOfLoopInstrToAlign instructions at head 575 // of a loop. It is used to determine the padding for loop alignment. 576 compute_loop_first_inst_sizes(); 577 578 uint nblocks = _cfg->_num_blocks; 579#ifdef ASSERT 580 uint* jmp_target = NEW_RESOURCE_ARRAY(uint,nblocks); 581 uint* jmp_offset = NEW_RESOURCE_ARRAY(uint,nblocks); 582 uint* jmp_size = NEW_RESOURCE_ARRAY(uint,nblocks); 583 uint* jmp_rule = NEW_RESOURCE_ARRAY(uint,nblocks); 584#endif 585 586 // Inserts nops where needed and do final short branches replacement. 587 uint nop_size = (new (this) MachNopNode())->size(_regalloc); 588 uint last_call_adr = max_uint; 589 uint last_avoid_back_to_back_adr = max_uint; 590 591 assert(blk_starts[0] == 0, "sanity"); 592 uint current_offset = 0; 593 uint block_alignment_padding = 0; 594 595 for (uint i=0; i < nblocks; i++) { // For all blocks 596 Block *b = _cfg->_blocks[i]; 597 598#ifdef ASSERT 599 jmp_target[i] = 0; 600 jmp_offset[i] = 0; 601 jmp_size[i] = 0; 602 jmp_rule[i] = 0; 603#endif 604 605 // Maximum alignment was added before loop block during 606 // Step One, as result padding for nodes was not added. 607 // Take this into account for block's size change check 608 // and allow increase block's size by the difference 609 // of maximum and actual alignment paddings. 610 DEBUG_ONLY( uint orig_blk_size = blk_starts[i+1] - blk_starts[i] + block_alignment_padding; ) 611 uint blk_offset = current_offset; 612 613 uint last_inst = b->_nodes.size(); 614 for (uint j = 0; j<last_inst; j++) { 615 Node* nj = b->_nodes[j]; 616 617 if (valid_bundle_info(nj) && 618 node_bundling(nj)->used_in_unconditional_delay()) { 619 continue; // Skip instruction in delay slot 620 } 621 622 uint inst_size = nj->size(_regalloc); 623 if (nj->is_Mach()) { 624 MachNode *mach = nj->as_Mach(); 625 int padding = mach->compute_padding(current_offset); 626 627 // If call/safepoint are adjacent insert a nop (5010568) 628 if (padding == 0 && nj->is_MachSafePoint() && !nj->is_MachCall() && 629 current_offset == last_call_adr) { 630 padding = nop_size; 631 } 632 633 // Inserted a nop between "avoid back to back" instructions. 634 if (padding == 0 && mach->avoid_back_to_back() && 635 current_offset == last_avoid_back_to_back_adr) { 636 padding = nop_size; 637 } 638 639 if (padding > 0) { 640 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size"); 641 int nops_cnt = padding / nop_size; 642 MachNode *nop = new (this) MachNopNode(nops_cnt); 643 b->_nodes.insert(j++, nop); 644 _cfg->_bbs.map(nop->_idx, b); 645 last_inst++; 646 current_offset += padding; 647 } 648 649 // Try to replace long branch if delay slot is not used, 650 // it is mostly for back branches since forward branch's 651 // distance is not updated yet. 652 bool delay_slot_is_used = valid_bundle_info(nj) && 653 node_bundling(nj)->use_unconditional_delay(); 654 if (!delay_slot_is_used && mach->may_be_short_branch()) { 655 int br_size = inst_size; 656 657 // This requires the TRUE branch target be in succs[0] 658 uint bnum = b->non_connector_successor(0)->_pre_order; 659 int offset = blk_starts[bnum] - current_offset; 660 if (bnum >= i) { 661 // Current and following block's offset are not 662 // finilized yet, adjust distance. 663 offset -= (blk_starts[i] - blk_offset); 664 } 665 // In the following code a nop could be inserted before 666 // the branch which will increase the backward distance. 667 bool needs_padding = (current_offset == last_avoid_back_to_back_adr); 668 if (needs_padding && offset <= 0) 669 offset -= nop_size; 670 671 if (_matcher->is_short_branch_offset(mach->rule(), br_size, offset)) { 672 // We've got a winner. Replace this branch. 673 MachNode* replacement = mach->short_branch_version(this); 674 675 // Update the jmp_size. 676 int new_size = replacement->size(_regalloc); 677 assert((br_size - new_size) >= (int)nop_size, "short_branch size should be smaller"); 678 // Conservatively take into accound padding between 679 // avoid_back_to_back branches. Previous branch could be 680 // converted into avoid_back_to_back branch during next 681 // rounds. 682 if (needs_padding && replacement->avoid_back_to_back()) { 683 MachNode *nop = new (this) MachNopNode(); 684 b->_nodes.insert(j++, nop); 685 _cfg->_bbs.map(nop->_idx, b); 686 last_inst++; 687 current_offset += nop_size; 688 } 689 inst_size = new_size; 690 b->_nodes.map(j, replacement); 691 mach->subsume_by(replacement); 692 nj = replacement; 693#ifdef ASSERT 694 jmp_target[i] = bnum; 695 jmp_offset[i] = current_offset - blk_offset; 696 jmp_size[i] = new_size; 697 jmp_rule[i] = mach->rule(); 698#endif 699 } 700 } 701 } 702 current_offset += inst_size; 703 704 // Remember end of call offset 705 if (nj->is_MachCall() && !nj->is_MachCallLeaf()) { 706 last_call_adr = current_offset; 707 } 708 // Remember end of avoid_back_to_back offset 709 if (nj->is_Mach() && nj->as_Mach()->avoid_back_to_back()) { 710 last_avoid_back_to_back_adr = current_offset; 711 } 712 } 713 assert(blk_offset <= blk_starts[i], "shouldn't increase distance"); 714 blk_starts[i] = blk_offset; 715 716 // When the next block is the top of a loop, we may insert pad NOP 717 // instructions. 718 if (i < nblocks-1) { 719 Block *nb = _cfg->_blocks[i+1]; 720 int padding = nb->alignment_padding(current_offset); 721 if (padding > 0) { 722 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size"); 723 int nops_cnt = padding / nop_size; 724 MachNode *nop = new (this) MachNopNode(nops_cnt); 725 b->_nodes.insert(b->_nodes.size(), nop); 726 _cfg->_bbs.map(nop->_idx, b); 727 current_offset += padding; 728 } 729 int max_loop_pad = nb->code_alignment()-relocInfo::addr_unit(); 730 assert(max_loop_pad >= padding, "sanity"); 731 block_alignment_padding = max_loop_pad - padding; 732 } 733 assert(orig_blk_size >= (current_offset - blk_offset), "shouldn't increase block size"); 734 } 735 blk_starts[nblocks] = current_offset; 736 737#ifdef ASSERT 738 for (uint i = 0; i < nblocks; i++) { // For all blocks 739 if (jmp_target[i] != 0) { 740 int br_size = jmp_size[i]; 741 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_offset[i]); 742 if (!_matcher->is_short_branch_offset(jmp_rule[i], br_size, offset)) { 743 tty->print_cr("target (%d) - jmp_offset(%d) = offset (%d), jump_size(%d), jmp_block B%d, target_block B%d", blk_starts[jmp_target[i]], blk_starts[i] + jmp_offset[i], offset, br_size, i, jmp_target[i]); 744 } 745 assert(_matcher->is_short_branch_offset(jmp_rule[i], br_size, offset), "Displacement too large for short jmp"); 746 } 747 } 748#endif 749} 750 751//------------------------------FillLocArray----------------------------------- 752// Create a bit of debug info and append it to the array. The mapping is from 753// Java local or expression stack to constant, register or stack-slot. For 754// doubles, insert 2 mappings and return 1 (to tell the caller that the next 755// entry has been taken care of and caller should skip it). 756static LocationValue *new_loc_value( PhaseRegAlloc *ra, OptoReg::Name regnum, Location::Type l_type ) { 757 // This should never have accepted Bad before 758 assert(OptoReg::is_valid(regnum), "location must be valid"); 759 return (OptoReg::is_reg(regnum)) 760 ? new LocationValue(Location::new_reg_loc(l_type, OptoReg::as_VMReg(regnum)) ) 761 : new LocationValue(Location::new_stk_loc(l_type, ra->reg2offset(regnum))); 762} 763 764 765ObjectValue* 766Compile::sv_for_node_id(GrowableArray<ScopeValue*> *objs, int id) { 767 for (int i = 0; i < objs->length(); i++) { 768 assert(objs->at(i)->is_object(), "corrupt object cache"); 769 ObjectValue* sv = (ObjectValue*) objs->at(i); 770 if (sv->id() == id) { 771 return sv; 772 } 773 } 774 // Otherwise.. 775 return NULL; 776} 777 778void Compile::set_sv_for_object_node(GrowableArray<ScopeValue*> *objs, 779 ObjectValue* sv ) { 780 assert(sv_for_node_id(objs, sv->id()) == NULL, "Precondition"); 781 objs->append(sv); 782} 783 784 785void Compile::FillLocArray( int idx, MachSafePointNode* sfpt, Node *local, 786 GrowableArray<ScopeValue*> *array, 787 GrowableArray<ScopeValue*> *objs ) { 788 assert( local, "use _top instead of null" ); 789 if (array->length() != idx) { 790 assert(array->length() == idx + 1, "Unexpected array count"); 791 // Old functionality: 792 // return 793 // New functionality: 794 // Assert if the local is not top. In product mode let the new node 795 // override the old entry. 796 assert(local == top(), "LocArray collision"); 797 if (local == top()) { 798 return; 799 } 800 array->pop(); 801 } 802 const Type *t = local->bottom_type(); 803 804 // Is it a safepoint scalar object node? 805 if (local->is_SafePointScalarObject()) { 806 SafePointScalarObjectNode* spobj = local->as_SafePointScalarObject(); 807 808 ObjectValue* sv = Compile::sv_for_node_id(objs, spobj->_idx); 809 if (sv == NULL) { 810 ciKlass* cik = t->is_oopptr()->klass(); 811 assert(cik->is_instance_klass() || 812 cik->is_array_klass(), "Not supported allocation."); 813 sv = new ObjectValue(spobj->_idx, 814 new ConstantOopWriteValue(cik->constant_encoding())); 815 Compile::set_sv_for_object_node(objs, sv); 816 817 uint first_ind = spobj->first_index(); 818 for (uint i = 0; i < spobj->n_fields(); i++) { 819 Node* fld_node = sfpt->in(first_ind+i); 820 (void)FillLocArray(sv->field_values()->length(), sfpt, fld_node, sv->field_values(), objs); 821 } 822 } 823 array->append(sv); 824 return; 825 } 826 827 // Grab the register number for the local 828 OptoReg::Name regnum = _regalloc->get_reg_first(local); 829 if( OptoReg::is_valid(regnum) ) {// Got a register/stack? 830 // Record the double as two float registers. 831 // The register mask for such a value always specifies two adjacent 832 // float registers, with the lower register number even. 833 // Normally, the allocation of high and low words to these registers 834 // is irrelevant, because nearly all operations on register pairs 835 // (e.g., StoreD) treat them as a single unit. 836 // Here, we assume in addition that the words in these two registers 837 // stored "naturally" (by operations like StoreD and double stores 838 // within the interpreter) such that the lower-numbered register 839 // is written to the lower memory address. This may seem like 840 // a machine dependency, but it is not--it is a requirement on 841 // the author of the <arch>.ad file to ensure that, for every 842 // even/odd double-register pair to which a double may be allocated, 843 // the word in the even single-register is stored to the first 844 // memory word. (Note that register numbers are completely 845 // arbitrary, and are not tied to any machine-level encodings.) 846#ifdef _LP64 847 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon ) { 848 array->append(new ConstantIntValue(0)); 849 array->append(new_loc_value( _regalloc, regnum, Location::dbl )); 850 } else if ( t->base() == Type::Long ) { 851 array->append(new ConstantIntValue(0)); 852 array->append(new_loc_value( _regalloc, regnum, Location::lng )); 853 } else if ( t->base() == Type::RawPtr ) { 854 // jsr/ret return address which must be restored into a the full 855 // width 64-bit stack slot. 856 array->append(new_loc_value( _regalloc, regnum, Location::lng )); 857 } 858#else //_LP64 859#ifdef SPARC 860 if (t->base() == Type::Long && OptoReg::is_reg(regnum)) { 861 // For SPARC we have to swap high and low words for 862 // long values stored in a single-register (g0-g7). 863 array->append(new_loc_value( _regalloc, regnum , Location::normal )); 864 array->append(new_loc_value( _regalloc, OptoReg::add(regnum,1), Location::normal )); 865 } else 866#endif //SPARC 867 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon || t->base() == Type::Long ) { 868 // Repack the double/long as two jints. 869 // The convention the interpreter uses is that the second local 870 // holds the first raw word of the native double representation. 871 // This is actually reasonable, since locals and stack arrays 872 // grow downwards in all implementations. 873 // (If, on some machine, the interpreter's Java locals or stack 874 // were to grow upwards, the embedded doubles would be word-swapped.) 875 array->append(new_loc_value( _regalloc, OptoReg::add(regnum,1), Location::normal )); 876 array->append(new_loc_value( _regalloc, regnum , Location::normal )); 877 } 878#endif //_LP64 879 else if( (t->base() == Type::FloatBot || t->base() == Type::FloatCon) && 880 OptoReg::is_reg(regnum) ) { 881 array->append(new_loc_value( _regalloc, regnum, Matcher::float_in_double() 882 ? Location::float_in_dbl : Location::normal )); 883 } else if( t->base() == Type::Int && OptoReg::is_reg(regnum) ) { 884 array->append(new_loc_value( _regalloc, regnum, Matcher::int_in_long 885 ? Location::int_in_long : Location::normal )); 886 } else if( t->base() == Type::NarrowOop ) { 887 array->append(new_loc_value( _regalloc, regnum, Location::narrowoop )); 888 } else { 889 array->append(new_loc_value( _regalloc, regnum, _regalloc->is_oop(local) ? Location::oop : Location::normal )); 890 } 891 return; 892 } 893 894 // No register. It must be constant data. 895 switch (t->base()) { 896 case Type::Half: // Second half of a double 897 ShouldNotReachHere(); // Caller should skip 2nd halves 898 break; 899 case Type::AnyPtr: 900 array->append(new ConstantOopWriteValue(NULL)); 901 break; 902 case Type::AryPtr: 903 case Type::InstPtr: 904 case Type::KlassPtr: // fall through 905 array->append(new ConstantOopWriteValue(t->isa_oopptr()->const_oop()->constant_encoding())); 906 break; 907 case Type::NarrowOop: 908 if (t == TypeNarrowOop::NULL_PTR) { 909 array->append(new ConstantOopWriteValue(NULL)); 910 } else { 911 array->append(new ConstantOopWriteValue(t->make_ptr()->isa_oopptr()->const_oop()->constant_encoding())); 912 } 913 break; 914 case Type::Int: 915 array->append(new ConstantIntValue(t->is_int()->get_con())); 916 break; 917 case Type::RawPtr: 918 // A return address (T_ADDRESS). 919 assert((intptr_t)t->is_ptr()->get_con() < (intptr_t)0x10000, "must be a valid BCI"); 920#ifdef _LP64 921 // Must be restored to the full-width 64-bit stack slot. 922 array->append(new ConstantLongValue(t->is_ptr()->get_con())); 923#else 924 array->append(new ConstantIntValue(t->is_ptr()->get_con())); 925#endif 926 break; 927 case Type::FloatCon: { 928 float f = t->is_float_constant()->getf(); 929 array->append(new ConstantIntValue(jint_cast(f))); 930 break; 931 } 932 case Type::DoubleCon: { 933 jdouble d = t->is_double_constant()->getd(); 934#ifdef _LP64 935 array->append(new ConstantIntValue(0)); 936 array->append(new ConstantDoubleValue(d)); 937#else 938 // Repack the double as two jints. 939 // The convention the interpreter uses is that the second local 940 // holds the first raw word of the native double representation. 941 // This is actually reasonable, since locals and stack arrays 942 // grow downwards in all implementations. 943 // (If, on some machine, the interpreter's Java locals or stack 944 // were to grow upwards, the embedded doubles would be word-swapped.) 945 jint *dp = (jint*)&d; 946 array->append(new ConstantIntValue(dp[1])); 947 array->append(new ConstantIntValue(dp[0])); 948#endif 949 break; 950 } 951 case Type::Long: { 952 jlong d = t->is_long()->get_con(); 953#ifdef _LP64 954 array->append(new ConstantIntValue(0)); 955 array->append(new ConstantLongValue(d)); 956#else 957 // Repack the long as two jints. 958 // The convention the interpreter uses is that the second local 959 // holds the first raw word of the native double representation. 960 // This is actually reasonable, since locals and stack arrays 961 // grow downwards in all implementations. 962 // (If, on some machine, the interpreter's Java locals or stack 963 // were to grow upwards, the embedded doubles would be word-swapped.) 964 jint *dp = (jint*)&d; 965 array->append(new ConstantIntValue(dp[1])); 966 array->append(new ConstantIntValue(dp[0])); 967#endif 968 break; 969 } 970 case Type::Top: // Add an illegal value here 971 array->append(new LocationValue(Location())); 972 break; 973 default: 974 ShouldNotReachHere(); 975 break; 976 } 977} 978 979// Determine if this node starts a bundle 980bool Compile::starts_bundle(const Node *n) const { 981 return (_node_bundling_limit > n->_idx && 982 _node_bundling_base[n->_idx].starts_bundle()); 983} 984 985//--------------------------Process_OopMap_Node-------------------------------- 986void Compile::Process_OopMap_Node(MachNode *mach, int current_offset) { 987 988 // Handle special safepoint nodes for synchronization 989 MachSafePointNode *sfn = mach->as_MachSafePoint(); 990 MachCallNode *mcall; 991 992#ifdef ENABLE_ZAP_DEAD_LOCALS 993 assert( is_node_getting_a_safepoint(mach), "logic does not match; false negative"); 994#endif 995 996 int safepoint_pc_offset = current_offset; 997 bool is_method_handle_invoke = false; 998 bool return_oop = false; 999 1000 // Add the safepoint in the DebugInfoRecorder 1001 if( !mach->is_MachCall() ) { 1002 mcall = NULL; 1003 debug_info()->add_safepoint(safepoint_pc_offset, sfn->_oop_map); 1004 } else { 1005 mcall = mach->as_MachCall(); 1006 1007 // Is the call a MethodHandle call? 1008 if (mcall->is_MachCallJava()) { 1009 if (mcall->as_MachCallJava()->_method_handle_invoke) { 1010 assert(has_method_handle_invokes(), "must have been set during call generation"); 1011 is_method_handle_invoke = true; 1012 } 1013 } 1014 1015 // Check if a call returns an object. 1016 if (mcall->return_value_is_used() && 1017 mcall->tf()->range()->field_at(TypeFunc::Parms)->isa_ptr()) { 1018 return_oop = true; 1019 } 1020 safepoint_pc_offset += mcall->ret_addr_offset(); 1021 debug_info()->add_safepoint(safepoint_pc_offset, mcall->_oop_map); 1022 } 1023 1024 // Loop over the JVMState list to add scope information 1025 // Do not skip safepoints with a NULL method, they need monitor info 1026 JVMState* youngest_jvms = sfn->jvms(); 1027 int max_depth = youngest_jvms->depth(); 1028 1029 // Allocate the object pool for scalar-replaced objects -- the map from 1030 // small-integer keys (which can be recorded in the local and ostack 1031 // arrays) to descriptions of the object state. 1032 GrowableArray<ScopeValue*> *objs = new GrowableArray<ScopeValue*>(); 1033 1034 // Visit scopes from oldest to youngest. 1035 for (int depth = 1; depth <= max_depth; depth++) { 1036 JVMState* jvms = youngest_jvms->of_depth(depth); 1037 int idx; 1038 ciMethod* method = jvms->has_method() ? jvms->method() : NULL; 1039 // Safepoints that do not have method() set only provide oop-map and monitor info 1040 // to support GC; these do not support deoptimization. 1041 int num_locs = (method == NULL) ? 0 : jvms->loc_size(); 1042 int num_exps = (method == NULL) ? 0 : jvms->stk_size(); 1043 int num_mon = jvms->nof_monitors(); 1044 assert(method == NULL || jvms->bci() < 0 || num_locs == method->max_locals(), 1045 "JVMS local count must match that of the method"); 1046 1047 // Add Local and Expression Stack Information 1048 1049 // Insert locals into the locarray 1050 GrowableArray<ScopeValue*> *locarray = new GrowableArray<ScopeValue*>(num_locs); 1051 for( idx = 0; idx < num_locs; idx++ ) { 1052 FillLocArray( idx, sfn, sfn->local(jvms, idx), locarray, objs ); 1053 } 1054 1055 // Insert expression stack entries into the exparray 1056 GrowableArray<ScopeValue*> *exparray = new GrowableArray<ScopeValue*>(num_exps); 1057 for( idx = 0; idx < num_exps; idx++ ) { 1058 FillLocArray( idx, sfn, sfn->stack(jvms, idx), exparray, objs ); 1059 } 1060 1061 // Add in mappings of the monitors 1062 assert( !method || 1063 !method->is_synchronized() || 1064 method->is_native() || 1065 num_mon > 0 || 1066 !GenerateSynchronizationCode, 1067 "monitors must always exist for synchronized methods"); 1068 1069 // Build the growable array of ScopeValues for exp stack 1070 GrowableArray<MonitorValue*> *monarray = new GrowableArray<MonitorValue*>(num_mon); 1071 1072 // Loop over monitors and insert into array 1073 for(idx = 0; idx < num_mon; idx++) { 1074 // Grab the node that defines this monitor 1075 Node* box_node = sfn->monitor_box(jvms, idx); 1076 Node* obj_node = sfn->monitor_obj(jvms, idx); 1077 1078 // Create ScopeValue for object 1079 ScopeValue *scval = NULL; 1080 1081 if( obj_node->is_SafePointScalarObject() ) { 1082 SafePointScalarObjectNode* spobj = obj_node->as_SafePointScalarObject(); 1083 scval = Compile::sv_for_node_id(objs, spobj->_idx); 1084 if (scval == NULL) { 1085 const Type *t = obj_node->bottom_type(); 1086 ciKlass* cik = t->is_oopptr()->klass(); 1087 assert(cik->is_instance_klass() || 1088 cik->is_array_klass(), "Not supported allocation."); 1089 ObjectValue* sv = new ObjectValue(spobj->_idx, 1090 new ConstantOopWriteValue(cik->constant_encoding())); 1091 Compile::set_sv_for_object_node(objs, sv); 1092 1093 uint first_ind = spobj->first_index(); 1094 for (uint i = 0; i < spobj->n_fields(); i++) { 1095 Node* fld_node = sfn->in(first_ind+i); 1096 (void)FillLocArray(sv->field_values()->length(), sfn, fld_node, sv->field_values(), objs); 1097 } 1098 scval = sv; 1099 } 1100 } else if( !obj_node->is_Con() ) { 1101 OptoReg::Name obj_reg = _regalloc->get_reg_first(obj_node); 1102 if( obj_node->bottom_type()->base() == Type::NarrowOop ) { 1103 scval = new_loc_value( _regalloc, obj_reg, Location::narrowoop ); 1104 } else { 1105 scval = new_loc_value( _regalloc, obj_reg, Location::oop ); 1106 } 1107 } else { 1108 const TypePtr *tp = obj_node->bottom_type()->make_ptr(); 1109 scval = new ConstantOopWriteValue(tp->is_oopptr()->const_oop()->constant_encoding()); 1110 } 1111 1112 OptoReg::Name box_reg = BoxLockNode::stack_slot(box_node); 1113 Location basic_lock = Location::new_stk_loc(Location::normal,_regalloc->reg2offset(box_reg)); 1114 while( !box_node->is_BoxLock() ) box_node = box_node->in(1); 1115 monarray->append(new MonitorValue(scval, basic_lock, box_node->as_BoxLock()->is_eliminated())); 1116 } 1117 1118 // We dump the object pool first, since deoptimization reads it in first. 1119 debug_info()->dump_object_pool(objs); 1120 1121 // Build first class objects to pass to scope 1122 DebugToken *locvals = debug_info()->create_scope_values(locarray); 1123 DebugToken *expvals = debug_info()->create_scope_values(exparray); 1124 DebugToken *monvals = debug_info()->create_monitor_values(monarray); 1125 1126 // Make method available for all Safepoints 1127 ciMethod* scope_method = method ? method : _method; 1128 // Describe the scope here 1129 assert(jvms->bci() >= InvocationEntryBci && jvms->bci() <= 0x10000, "must be a valid or entry BCI"); 1130 assert(!jvms->should_reexecute() || depth == max_depth, "reexecute allowed only for the youngest"); 1131 // Now we can describe the scope. 1132 debug_info()->describe_scope(safepoint_pc_offset, scope_method, jvms->bci(), jvms->should_reexecute(), is_method_handle_invoke, return_oop, locvals, expvals, monvals); 1133 } // End jvms loop 1134 1135 // Mark the end of the scope set. 1136 debug_info()->end_safepoint(safepoint_pc_offset); 1137} 1138 1139 1140 1141// A simplified version of Process_OopMap_Node, to handle non-safepoints. 1142class NonSafepointEmitter { 1143 Compile* C; 1144 JVMState* _pending_jvms; 1145 int _pending_offset; 1146 1147 void emit_non_safepoint(); 1148 1149 public: 1150 NonSafepointEmitter(Compile* compile) { 1151 this->C = compile; 1152 _pending_jvms = NULL; 1153 _pending_offset = 0; 1154 } 1155 1156 void observe_instruction(Node* n, int pc_offset) { 1157 if (!C->debug_info()->recording_non_safepoints()) return; 1158 1159 Node_Notes* nn = C->node_notes_at(n->_idx); 1160 if (nn == NULL || nn->jvms() == NULL) return; 1161 if (_pending_jvms != NULL && 1162 _pending_jvms->same_calls_as(nn->jvms())) { 1163 // Repeated JVMS? Stretch it up here. 1164 _pending_offset = pc_offset; 1165 } else { 1166 if (_pending_jvms != NULL && 1167 _pending_offset < pc_offset) { 1168 emit_non_safepoint(); 1169 } 1170 _pending_jvms = NULL; 1171 if (pc_offset > C->debug_info()->last_pc_offset()) { 1172 // This is the only way _pending_jvms can become non-NULL: 1173 _pending_jvms = nn->jvms(); 1174 _pending_offset = pc_offset; 1175 } 1176 } 1177 } 1178 1179 // Stay out of the way of real safepoints: 1180 void observe_safepoint(JVMState* jvms, int pc_offset) { 1181 if (_pending_jvms != NULL && 1182 !_pending_jvms->same_calls_as(jvms) && 1183 _pending_offset < pc_offset) { 1184 emit_non_safepoint(); 1185 } 1186 _pending_jvms = NULL; 1187 } 1188 1189 void flush_at_end() { 1190 if (_pending_jvms != NULL) { 1191 emit_non_safepoint(); 1192 } 1193 _pending_jvms = NULL; 1194 } 1195}; 1196 1197void NonSafepointEmitter::emit_non_safepoint() { 1198 JVMState* youngest_jvms = _pending_jvms; 1199 int pc_offset = _pending_offset; 1200 1201 // Clear it now: 1202 _pending_jvms = NULL; 1203 1204 DebugInformationRecorder* debug_info = C->debug_info(); 1205 assert(debug_info->recording_non_safepoints(), "sanity"); 1206 1207 debug_info->add_non_safepoint(pc_offset); 1208 int max_depth = youngest_jvms->depth(); 1209 1210 // Visit scopes from oldest to youngest. 1211 for (int depth = 1; depth <= max_depth; depth++) { 1212 JVMState* jvms = youngest_jvms->of_depth(depth); 1213 ciMethod* method = jvms->has_method() ? jvms->method() : NULL; 1214 assert(!jvms->should_reexecute() || depth==max_depth, "reexecute allowed only for the youngest"); 1215 debug_info->describe_scope(pc_offset, method, jvms->bci(), jvms->should_reexecute()); 1216 } 1217 1218 // Mark the end of the scope set. 1219 debug_info->end_non_safepoint(pc_offset); 1220} 1221 1222 1223 1224// helper for fill_buffer bailout logic 1225static void turn_off_compiler(Compile* C) { 1226 if (CodeCache::largest_free_block() >= CodeCacheMinimumFreeSpace*10) { 1227 // Do not turn off compilation if a single giant method has 1228 // blown the code cache size. 1229 C->record_failure("excessive request to CodeCache"); 1230 } else { 1231 // Let CompilerBroker disable further compilations. 1232 C->record_failure("CodeCache is full"); 1233 } 1234} 1235 1236 1237//------------------------------init_buffer------------------------------------ 1238CodeBuffer* Compile::init_buffer(uint* blk_starts) { 1239 1240 // Set the initially allocated size 1241 int code_req = initial_code_capacity; 1242 int locs_req = initial_locs_capacity; 1243 int stub_req = TraceJumps ? initial_stub_capacity * 10 : initial_stub_capacity; 1244 int const_req = initial_const_capacity; 1245 1246 int pad_req = NativeCall::instruction_size; 1247 // The extra spacing after the code is necessary on some platforms. 1248 // Sometimes we need to patch in a jump after the last instruction, 1249 // if the nmethod has been deoptimized. (See 4932387, 4894843.) 1250 1251 // Compute the byte offset where we can store the deopt pc. 1252 if (fixed_slots() != 0) { 1253 _orig_pc_slot_offset_in_bytes = _regalloc->reg2offset(OptoReg::stack2reg(_orig_pc_slot)); 1254 } 1255 1256 // Compute prolog code size 1257 _method_size = 0; 1258 _frame_slots = OptoReg::reg2stack(_matcher->_old_SP)+_regalloc->_framesize; 1259#ifdef IA64 1260 if (save_argument_registers()) { 1261 // 4815101: this is a stub with implicit and unknown precision fp args. 1262 // The usual spill mechanism can only generate stfd's in this case, which 1263 // doesn't work if the fp reg to spill contains a single-precision denorm. 1264 // Instead, we hack around the normal spill mechanism using stfspill's and 1265 // ldffill's in the MachProlog and MachEpilog emit methods. We allocate 1266 // space here for the fp arg regs (f8-f15) we're going to thusly spill. 1267 // 1268 // If we ever implement 16-byte 'registers' == stack slots, we can 1269 // get rid of this hack and have SpillCopy generate stfspill/ldffill 1270 // instead of stfd/stfs/ldfd/ldfs. 1271 _frame_slots += 8*(16/BytesPerInt); 1272 } 1273#endif 1274 assert(_frame_slots >= 0 && _frame_slots < 1000000, "sanity check"); 1275 1276 if (has_mach_constant_base_node()) { 1277 // Fill the constant table. 1278 // Note: This must happen before shorten_branches. 1279 for (uint i = 0; i < _cfg->_num_blocks; i++) { 1280 Block* b = _cfg->_blocks[i]; 1281 1282 for (uint j = 0; j < b->_nodes.size(); j++) { 1283 Node* n = b->_nodes[j]; 1284 1285 // If the node is a MachConstantNode evaluate the constant 1286 // value section. 1287 if (n->is_MachConstant()) { 1288 MachConstantNode* machcon = n->as_MachConstant(); 1289 machcon->eval_constant(C); 1290 } 1291 } 1292 } 1293 1294 // Calculate the offsets of the constants and the size of the 1295 // constant table (including the padding to the next section). 1296 constant_table().calculate_offsets_and_size(); 1297 const_req = constant_table().size(); 1298 } 1299 1300 // Initialize the space for the BufferBlob used to find and verify 1301 // instruction size in MachNode::emit_size() 1302 init_scratch_buffer_blob(const_req); 1303 if (failing()) return NULL; // Out of memory 1304 1305 // Pre-compute the length of blocks and replace 1306 // long branches with short if machine supports it. 1307 shorten_branches(blk_starts, code_req, locs_req, stub_req); 1308 1309 // nmethod and CodeBuffer count stubs & constants as part of method's code. 1310 int exception_handler_req = size_exception_handler(); 1311 int deopt_handler_req = size_deopt_handler(); 1312 exception_handler_req += MAX_stubs_size; // add marginal slop for handler 1313 deopt_handler_req += MAX_stubs_size; // add marginal slop for handler 1314 stub_req += MAX_stubs_size; // ensure per-stub margin 1315 code_req += MAX_inst_size; // ensure per-instruction margin 1316 1317 if (StressCodeBuffers) 1318 code_req = const_req = stub_req = exception_handler_req = deopt_handler_req = 0x10; // force expansion 1319 1320 int total_req = 1321 const_req + 1322 code_req + 1323 pad_req + 1324 stub_req + 1325 exception_handler_req + 1326 deopt_handler_req; // deopt handler 1327 1328 if (has_method_handle_invokes()) 1329 total_req += deopt_handler_req; // deopt MH handler 1330 1331 CodeBuffer* cb = code_buffer(); 1332 cb->initialize(total_req, locs_req); 1333 1334 // Have we run out of code space? 1335 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { 1336 turn_off_compiler(this); 1337 return NULL; 1338 } 1339 // Configure the code buffer. 1340 cb->initialize_consts_size(const_req); 1341 cb->initialize_stubs_size(stub_req); 1342 cb->initialize_oop_recorder(env()->oop_recorder()); 1343 1344 // fill in the nop array for bundling computations 1345 MachNode *_nop_list[Bundle::_nop_count]; 1346 Bundle::initialize_nops(_nop_list, this); 1347 1348 return cb; 1349} 1350 1351//------------------------------fill_buffer------------------------------------ 1352void Compile::fill_buffer(CodeBuffer* cb, uint* blk_starts) { 1353 1354 // Create oopmap set. 1355 _oop_map_set = new OopMapSet(); 1356 1357 // !!!!! This preserves old handling of oopmaps for now 1358 debug_info()->set_oopmaps(_oop_map_set); 1359 1360 // Count and start of implicit null check instructions 1361 uint inct_cnt = 0; 1362 uint *inct_starts = NEW_RESOURCE_ARRAY(uint, _cfg->_num_blocks+1); 1363 1364 // Count and start of calls 1365 uint *call_returns = NEW_RESOURCE_ARRAY(uint, _cfg->_num_blocks+1); 1366 1367 uint return_offset = 0; 1368 int nop_size = (new (this) MachNopNode())->size(_regalloc); 1369 1370 int previous_offset = 0; 1371 int current_offset = 0; 1372#ifdef ASSERT 1373 int last_call_offset = -1; 1374 int last_avoid_back_to_back_offset = -1; 1375#endif 1376 // Create an array of unused labels, one for each basic block, if printing is enabled 1377#ifndef PRODUCT 1378 int *node_offsets = NULL; 1379 uint node_offset_limit = unique(); 1380 1381 if (print_assembly()) 1382 node_offsets = NEW_RESOURCE_ARRAY(int, node_offset_limit); 1383#endif 1384 1385 NonSafepointEmitter non_safepoints(this); // emit non-safepoints lazily 1386 1387 // Emit the constant table. 1388 if (has_mach_constant_base_node()) { 1389 constant_table().emit(*cb); 1390 } 1391 1392 // Create an array of labels, one for each basic block 1393 Label *blk_labels = NEW_RESOURCE_ARRAY(Label, _cfg->_num_blocks+1); 1394 for (uint i=0; i <= _cfg->_num_blocks; i++) { 1395 blk_labels[i].init(); 1396 } 1397 1398 // ------------------ 1399 // Now fill in the code buffer 1400 Node *delay_slot = NULL; 1401 1402 for (uint i=0; i < _cfg->_num_blocks; i++) { 1403 guarantee(blk_starts[i] == (uint)cb->insts_size(),"should not change size"); 1404 1405 Block *b = _cfg->_blocks[i]; 1406 1407 Node *head = b->head(); 1408 1409 // If this block needs to start aligned (i.e, can be reached other 1410 // than by falling-thru from the previous block), then force the 1411 // start of a new bundle. 1412 if (Pipeline::requires_bundling() && starts_bundle(head)) 1413 cb->flush_bundle(true); 1414 1415#ifdef ASSERT 1416 if (!b->is_connector()) { 1417 stringStream st; 1418 b->dump_head(&_cfg->_bbs, &st); 1419 MacroAssembler(cb).block_comment(st.as_string()); 1420 } 1421#endif 1422 1423 // Define the label at the beginning of the basic block 1424 MacroAssembler(cb).bind(blk_labels[b->_pre_order]); 1425 1426 uint last_inst = b->_nodes.size(); 1427 1428 // Emit block normally, except for last instruction. 1429 // Emit means "dump code bits into code buffer". 1430 for (uint j = 0; j<last_inst; j++) { 1431 1432 // Get the node 1433 Node* n = b->_nodes[j]; 1434 1435 // See if delay slots are supported 1436 if (valid_bundle_info(n) && 1437 node_bundling(n)->used_in_unconditional_delay()) { 1438 assert(delay_slot == NULL, "no use of delay slot node"); 1439 assert(n->size(_regalloc) == Pipeline::instr_unit_size(), "delay slot instruction wrong size"); 1440 1441 delay_slot = n; 1442 continue; 1443 } 1444 1445 // If this starts a new instruction group, then flush the current one 1446 // (but allow split bundles) 1447 if (Pipeline::requires_bundling() && starts_bundle(n)) 1448 cb->flush_bundle(false); 1449 1450 // The following logic is duplicated in the code ifdeffed for 1451 // ENABLE_ZAP_DEAD_LOCALS which appears above in this file. It 1452 // should be factored out. Or maybe dispersed to the nodes? 1453 1454 // Special handling for SafePoint/Call Nodes 1455 bool is_mcall = false; 1456 if (n->is_Mach()) { 1457 MachNode *mach = n->as_Mach(); 1458 is_mcall = n->is_MachCall(); 1459 bool is_sfn = n->is_MachSafePoint(); 1460 1461 // If this requires all previous instructions be flushed, then do so 1462 if (is_sfn || is_mcall || mach->alignment_required() != 1) { 1463 cb->flush_bundle(true); 1464 current_offset = cb->insts_size(); 1465 } 1466 1467#ifdef ASSERT 1468 // A padding may be needed again since a previous instruction 1469 // could be moved to delay slot. 1470 1471 // align the instruction if necessary 1472 int padding = mach->compute_padding(current_offset); 1473 // Make sure safepoint node for polling is distinct from a call's 1474 // return by adding a nop if needed. 1475 if (is_sfn && !is_mcall && padding == 0 && current_offset == last_call_offset) { 1476 padding = nop_size; 1477 } 1478 if (padding == 0 && mach->avoid_back_to_back() && 1479 current_offset == last_avoid_back_to_back_offset) { 1480 // Avoid back to back some instructions. 1481 padding = nop_size; 1482 } 1483 assert(padding == 0, "padding should be added already"); 1484#endif 1485 // Remember the start of the last call in a basic block 1486 if (is_mcall) { 1487 MachCallNode *mcall = mach->as_MachCall(); 1488 1489 // This destination address is NOT PC-relative 1490 mcall->method_set((intptr_t)mcall->entry_point()); 1491 1492 // Save the return address 1493 call_returns[b->_pre_order] = current_offset + mcall->ret_addr_offset(); 1494 1495 if (mcall->is_MachCallLeaf()) { 1496 is_mcall = false; 1497 is_sfn = false; 1498 } 1499 } 1500 1501 // sfn will be valid whenever mcall is valid now because of inheritance 1502 if (is_sfn || is_mcall) { 1503 1504 // Handle special safepoint nodes for synchronization 1505 if (!is_mcall) { 1506 MachSafePointNode *sfn = mach->as_MachSafePoint(); 1507 // !!!!! Stubs only need an oopmap right now, so bail out 1508 if (sfn->jvms()->method() == NULL) { 1509 // Write the oopmap directly to the code blob??!! 1510# ifdef ENABLE_ZAP_DEAD_LOCALS 1511 assert( !is_node_getting_a_safepoint(sfn), "logic does not match; false positive"); 1512# endif 1513 continue; 1514 } 1515 } // End synchronization 1516 1517 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(), 1518 current_offset); 1519 Process_OopMap_Node(mach, current_offset); 1520 } // End if safepoint 1521 1522 // If this is a null check, then add the start of the previous instruction to the list 1523 else if( mach->is_MachNullCheck() ) { 1524 inct_starts[inct_cnt++] = previous_offset; 1525 } 1526 1527 // If this is a branch, then fill in the label with the target BB's label 1528 else if (mach->is_Branch()) { 1529 1530 if (mach->ideal_Opcode() == Op_Jump) { 1531 for (uint h = 0; h < b->_num_succs; h++) { 1532 Block* succs_block = b->_succs[h]; 1533 for (uint j = 1; j < succs_block->num_preds(); j++) { 1534 Node* jpn = succs_block->pred(j); 1535 if (jpn->is_JumpProj() && jpn->in(0) == mach) { 1536 uint block_num = succs_block->non_connector()->_pre_order; 1537 Label *blkLabel = &blk_labels[block_num]; 1538 mach->add_case_label(jpn->as_JumpProj()->proj_no(), blkLabel); 1539 } 1540 } 1541 } 1542 } else { 1543 // For Branchs 1544 // This requires the TRUE branch target be in succs[0] 1545 uint block_num = b->non_connector_successor(0)->_pre_order; 1546 mach->label_set( &blk_labels[block_num], block_num ); 1547 } 1548 } 1549 1550#ifdef ASSERT 1551 // Check that oop-store precedes the card-mark 1552 else if (mach->ideal_Opcode() == Op_StoreCM) { 1553 uint storeCM_idx = j; 1554 int count = 0; 1555 for (uint prec = mach->req(); prec < mach->len(); prec++) { 1556 Node *oop_store = mach->in(prec); // Precedence edge 1557 if (oop_store == NULL) continue; 1558 count++; 1559 uint i4; 1560 for( i4 = 0; i4 < last_inst; ++i4 ) { 1561 if( b->_nodes[i4] == oop_store ) break; 1562 } 1563 // Note: This test can provide a false failure if other precedence 1564 // edges have been added to the storeCMNode. 1565 assert( i4 == last_inst || i4 < storeCM_idx, "CM card-mark executes before oop-store"); 1566 } 1567 assert(count > 0, "storeCM expects at least one precedence edge"); 1568 } 1569#endif 1570 1571 else if (!n->is_Proj()) { 1572 // Remember the beginning of the previous instruction, in case 1573 // it's followed by a flag-kill and a null-check. Happens on 1574 // Intel all the time, with add-to-memory kind of opcodes. 1575 previous_offset = current_offset; 1576 } 1577 } 1578 1579 // Verify that there is sufficient space remaining 1580 cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size); 1581 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { 1582 turn_off_compiler(this); 1583 return; 1584 } 1585 1586 // Save the offset for the listing 1587#ifndef PRODUCT 1588 if (node_offsets && n->_idx < node_offset_limit) 1589 node_offsets[n->_idx] = cb->insts_size(); 1590#endif 1591 1592 // "Normal" instruction case 1593 DEBUG_ONLY( uint instr_offset = cb->insts_size(); ) 1594 n->emit(*cb, _regalloc); 1595 current_offset = cb->insts_size(); 1596 1597#ifdef ASSERT 1598 if (n->size(_regalloc) != (current_offset-instr_offset)) { 1599 n->dump(); 1600 assert(n->size(_regalloc) == (current_offset-instr_offset), "wrong size of mach node"); 1601 } 1602#endif 1603 non_safepoints.observe_instruction(n, current_offset); 1604 1605#ifdef ASSERT 1606 // mcall is last "call" that can be a safepoint 1607 // record it so we can see if a poll will directly follow it 1608 // in which case we'll need a pad to make the PcDesc sites unique 1609 // see 5010568. This can be slightly inaccurate but conservative 1610 // in the case that return address is not actually at current_offset. 1611 // This is a small price to pay. 1612 1613 if (is_mcall) { 1614 last_call_offset = current_offset; 1615 } 1616 1617 if (n->is_Mach() && n->as_Mach()->avoid_back_to_back()) { 1618 // Avoid back to back some instructions. 1619 last_avoid_back_to_back_offset = current_offset; 1620 } 1621#endif 1622 1623 // See if this instruction has a delay slot 1624 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) { 1625 assert(delay_slot != NULL, "expecting delay slot node"); 1626 1627 // Back up 1 instruction 1628 cb->set_insts_end(cb->insts_end() - Pipeline::instr_unit_size()); 1629 1630 // Save the offset for the listing 1631#ifndef PRODUCT 1632 if (node_offsets && delay_slot->_idx < node_offset_limit) 1633 node_offsets[delay_slot->_idx] = cb->insts_size(); 1634#endif 1635 1636 // Support a SafePoint in the delay slot 1637 if (delay_slot->is_MachSafePoint()) { 1638 MachNode *mach = delay_slot->as_Mach(); 1639 // !!!!! Stubs only need an oopmap right now, so bail out 1640 if (!mach->is_MachCall() && mach->as_MachSafePoint()->jvms()->method() == NULL) { 1641 // Write the oopmap directly to the code blob??!! 1642# ifdef ENABLE_ZAP_DEAD_LOCALS 1643 assert( !is_node_getting_a_safepoint(mach), "logic does not match; false positive"); 1644# endif 1645 delay_slot = NULL; 1646 continue; 1647 } 1648 1649 int adjusted_offset = current_offset - Pipeline::instr_unit_size(); 1650 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(), 1651 adjusted_offset); 1652 // Generate an OopMap entry 1653 Process_OopMap_Node(mach, adjusted_offset); 1654 } 1655 1656 // Insert the delay slot instruction 1657 delay_slot->emit(*cb, _regalloc); 1658 1659 // Don't reuse it 1660 delay_slot = NULL; 1661 } 1662 1663 } // End for all instructions in block 1664#ifdef ASSERT 1665 // If the next block is the top of a loop, pad this block out to align 1666 // the loop top a little. Helps prevent pipe stalls at loop back branches. 1667 if (i < _cfg->_num_blocks-1) { 1668 Block *nb = _cfg->_blocks[i+1]; 1669 uint padding = nb->alignment_padding(current_offset); 1670 assert(padding == 0, "alignment should be added already"); 1671 } 1672#endif 1673 } // End of for all blocks 1674 1675 non_safepoints.flush_at_end(); 1676 1677 // Offset too large? 1678 if (failing()) return; 1679 1680 // Define a pseudo-label at the end of the code 1681 MacroAssembler(cb).bind( blk_labels[_cfg->_num_blocks] ); 1682 1683 // Compute the size of the first block 1684 _first_block_size = blk_labels[1].loc_pos() - blk_labels[0].loc_pos(); 1685 1686 assert(cb->insts_size() < 500000, "method is unreasonably large"); 1687 1688 // ------------------ 1689 1690#ifndef PRODUCT 1691 // Information on the size of the method, without the extraneous code 1692 Scheduling::increment_method_size(cb->insts_size()); 1693#endif 1694 1695 // ------------------ 1696 // Fill in exception table entries. 1697 FillExceptionTables(inct_cnt, call_returns, inct_starts, blk_labels); 1698 1699 // Only java methods have exception handlers and deopt handlers 1700 if (_method) { 1701 // Emit the exception handler code. 1702 _code_offsets.set_value(CodeOffsets::Exceptions, emit_exception_handler(*cb)); 1703 // Emit the deopt handler code. 1704 _code_offsets.set_value(CodeOffsets::Deopt, emit_deopt_handler(*cb)); 1705 1706 // Emit the MethodHandle deopt handler code (if required). 1707 if (has_method_handle_invokes()) { 1708 // We can use the same code as for the normal deopt handler, we 1709 // just need a different entry point address. 1710 _code_offsets.set_value(CodeOffsets::DeoptMH, emit_deopt_handler(*cb)); 1711 } 1712 } 1713 1714 // One last check for failed CodeBuffer::expand: 1715 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { 1716 turn_off_compiler(this); 1717 return; 1718 } 1719 1720#ifndef PRODUCT 1721 // Dump the assembly code, including basic-block numbers 1722 if (print_assembly()) { 1723 ttyLocker ttyl; // keep the following output all in one block 1724 if (!VMThread::should_terminate()) { // test this under the tty lock 1725 // This output goes directly to the tty, not the compiler log. 1726 // To enable tools to match it up with the compilation activity, 1727 // be sure to tag this tty output with the compile ID. 1728 if (xtty != NULL) { 1729 xtty->head("opto_assembly compile_id='%d'%s", compile_id(), 1730 is_osr_compilation() ? " compile_kind='osr'" : 1731 ""); 1732 } 1733 if (method() != NULL) { 1734 method()->print_oop(); 1735 print_codes(); 1736 } 1737 dump_asm(node_offsets, node_offset_limit); 1738 if (xtty != NULL) { 1739 xtty->tail("opto_assembly"); 1740 } 1741 } 1742 } 1743#endif 1744 1745} 1746 1747void Compile::FillExceptionTables(uint cnt, uint *call_returns, uint *inct_starts, Label *blk_labels) { 1748 _inc_table.set_size(cnt); 1749 1750 uint inct_cnt = 0; 1751 for( uint i=0; i<_cfg->_num_blocks; i++ ) { 1752 Block *b = _cfg->_blocks[i]; 1753 Node *n = NULL; 1754 int j; 1755 1756 // Find the branch; ignore trailing NOPs. 1757 for( j = b->_nodes.size()-1; j>=0; j-- ) { 1758 n = b->_nodes[j]; 1759 if( !n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con ) 1760 break; 1761 } 1762 1763 // If we didn't find anything, continue 1764 if( j < 0 ) continue; 1765 1766 // Compute ExceptionHandlerTable subtable entry and add it 1767 // (skip empty blocks) 1768 if( n->is_Catch() ) { 1769 1770 // Get the offset of the return from the call 1771 uint call_return = call_returns[b->_pre_order]; 1772#ifdef ASSERT 1773 assert( call_return > 0, "no call seen for this basic block" ); 1774 while( b->_nodes[--j]->is_MachProj() ) ; 1775 assert( b->_nodes[j]->is_MachCall(), "CatchProj must follow call" ); 1776#endif 1777 // last instruction is a CatchNode, find it's CatchProjNodes 1778 int nof_succs = b->_num_succs; 1779 // allocate space 1780 GrowableArray<intptr_t> handler_bcis(nof_succs); 1781 GrowableArray<intptr_t> handler_pcos(nof_succs); 1782 // iterate through all successors 1783 for (int j = 0; j < nof_succs; j++) { 1784 Block* s = b->_succs[j]; 1785 bool found_p = false; 1786 for( uint k = 1; k < s->num_preds(); k++ ) { 1787 Node *pk = s->pred(k); 1788 if( pk->is_CatchProj() && pk->in(0) == n ) { 1789 const CatchProjNode* p = pk->as_CatchProj(); 1790 found_p = true; 1791 // add the corresponding handler bci & pco information 1792 if( p->_con != CatchProjNode::fall_through_index ) { 1793 // p leads to an exception handler (and is not fall through) 1794 assert(s == _cfg->_blocks[s->_pre_order],"bad numbering"); 1795 // no duplicates, please 1796 if( !handler_bcis.contains(p->handler_bci()) ) { 1797 uint block_num = s->non_connector()->_pre_order; 1798 handler_bcis.append(p->handler_bci()); 1799 handler_pcos.append(blk_labels[block_num].loc_pos()); 1800 } 1801 } 1802 } 1803 } 1804 assert(found_p, "no matching predecessor found"); 1805 // Note: Due to empty block removal, one block may have 1806 // several CatchProj inputs, from the same Catch. 1807 } 1808 1809 // Set the offset of the return from the call 1810 _handler_table.add_subtable(call_return, &handler_bcis, NULL, &handler_pcos); 1811 continue; 1812 } 1813 1814 // Handle implicit null exception table updates 1815 if( n->is_MachNullCheck() ) { 1816 uint block_num = b->non_connector_successor(0)->_pre_order; 1817 _inc_table.append( inct_starts[inct_cnt++], blk_labels[block_num].loc_pos() ); 1818 continue; 1819 } 1820 } // End of for all blocks fill in exception table entries 1821} 1822 1823// Static Variables 1824#ifndef PRODUCT 1825uint Scheduling::_total_nop_size = 0; 1826uint Scheduling::_total_method_size = 0; 1827uint Scheduling::_total_branches = 0; 1828uint Scheduling::_total_unconditional_delays = 0; 1829uint Scheduling::_total_instructions_per_bundle[Pipeline::_max_instrs_per_cycle+1]; 1830#endif 1831 1832// Initializer for class Scheduling 1833 1834Scheduling::Scheduling(Arena *arena, Compile &compile) 1835 : _arena(arena), 1836 _cfg(compile.cfg()), 1837 _bbs(compile.cfg()->_bbs), 1838 _regalloc(compile.regalloc()), 1839 _reg_node(arena), 1840 _bundle_instr_count(0), 1841 _bundle_cycle_number(0), 1842 _scheduled(arena), 1843 _available(arena), 1844 _next_node(NULL), 1845 _bundle_use(0, 0, resource_count, &_bundle_use_elements[0]), 1846 _pinch_free_list(arena) 1847#ifndef PRODUCT 1848 , _branches(0) 1849 , _unconditional_delays(0) 1850#endif 1851{ 1852 // Create a MachNopNode 1853 _nop = new (&compile) MachNopNode(); 1854 1855 // Now that the nops are in the array, save the count 1856 // (but allow entries for the nops) 1857 _node_bundling_limit = compile.unique(); 1858 uint node_max = _regalloc->node_regs_max_index(); 1859 1860 compile.set_node_bundling_limit(_node_bundling_limit); 1861 1862 // This one is persistent within the Compile class 1863 _node_bundling_base = NEW_ARENA_ARRAY(compile.comp_arena(), Bundle, node_max); 1864 1865 // Allocate space for fixed-size arrays 1866 _node_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max); 1867 _uses = NEW_ARENA_ARRAY(arena, short, node_max); 1868 _current_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max); 1869 1870 // Clear the arrays 1871 memset(_node_bundling_base, 0, node_max * sizeof(Bundle)); 1872 memset(_node_latency, 0, node_max * sizeof(unsigned short)); 1873 memset(_uses, 0, node_max * sizeof(short)); 1874 memset(_current_latency, 0, node_max * sizeof(unsigned short)); 1875 1876 // Clear the bundling information 1877 memcpy(_bundle_use_elements, 1878 Pipeline_Use::elaborated_elements, 1879 sizeof(Pipeline_Use::elaborated_elements)); 1880 1881 // Get the last node 1882 Block *bb = _cfg->_blocks[_cfg->_blocks.size()-1]; 1883 1884 _next_node = bb->_nodes[bb->_nodes.size()-1]; 1885} 1886 1887#ifndef PRODUCT 1888// Scheduling destructor 1889Scheduling::~Scheduling() { 1890 _total_branches += _branches; 1891 _total_unconditional_delays += _unconditional_delays; 1892} 1893#endif 1894 1895// Step ahead "i" cycles 1896void Scheduling::step(uint i) { 1897 1898 Bundle *bundle = node_bundling(_next_node); 1899 bundle->set_starts_bundle(); 1900 1901 // Update the bundle record, but leave the flags information alone 1902 if (_bundle_instr_count > 0) { 1903 bundle->set_instr_count(_bundle_instr_count); 1904 bundle->set_resources_used(_bundle_use.resourcesUsed()); 1905 } 1906 1907 // Update the state information 1908 _bundle_instr_count = 0; 1909 _bundle_cycle_number += i; 1910 _bundle_use.step(i); 1911} 1912 1913void Scheduling::step_and_clear() { 1914 Bundle *bundle = node_bundling(_next_node); 1915 bundle->set_starts_bundle(); 1916 1917 // Update the bundle record 1918 if (_bundle_instr_count > 0) { 1919 bundle->set_instr_count(_bundle_instr_count); 1920 bundle->set_resources_used(_bundle_use.resourcesUsed()); 1921 1922 _bundle_cycle_number += 1; 1923 } 1924 1925 // Clear the bundling information 1926 _bundle_instr_count = 0; 1927 _bundle_use.reset(); 1928 1929 memcpy(_bundle_use_elements, 1930 Pipeline_Use::elaborated_elements, 1931 sizeof(Pipeline_Use::elaborated_elements)); 1932} 1933 1934//------------------------------ScheduleAndBundle------------------------------ 1935// Perform instruction scheduling and bundling over the sequence of 1936// instructions in backwards order. 1937void Compile::ScheduleAndBundle() { 1938 1939 // Don't optimize this if it isn't a method 1940 if (!_method) 1941 return; 1942 1943 // Don't optimize this if scheduling is disabled 1944 if (!do_scheduling()) 1945 return; 1946 1947 NOT_PRODUCT( TracePhase t2("isched", &_t_instrSched, TimeCompiler); ) 1948 1949 // Create a data structure for all the scheduling information 1950 Scheduling scheduling(Thread::current()->resource_area(), *this); 1951 1952 // Walk backwards over each basic block, computing the needed alignment 1953 // Walk over all the basic blocks 1954 scheduling.DoScheduling(); 1955} 1956 1957//------------------------------ComputeLocalLatenciesForward------------------- 1958// Compute the latency of all the instructions. This is fairly simple, 1959// because we already have a legal ordering. Walk over the instructions 1960// from first to last, and compute the latency of the instruction based 1961// on the latency of the preceding instruction(s). 1962void Scheduling::ComputeLocalLatenciesForward(const Block *bb) { 1963#ifndef PRODUCT 1964 if (_cfg->C->trace_opto_output()) 1965 tty->print("# -> ComputeLocalLatenciesForward\n"); 1966#endif 1967 1968 // Walk over all the schedulable instructions 1969 for( uint j=_bb_start; j < _bb_end; j++ ) { 1970 1971 // This is a kludge, forcing all latency calculations to start at 1. 1972 // Used to allow latency 0 to force an instruction to the beginning 1973 // of the bb 1974 uint latency = 1; 1975 Node *use = bb->_nodes[j]; 1976 uint nlen = use->len(); 1977 1978 // Walk over all the inputs 1979 for ( uint k=0; k < nlen; k++ ) { 1980 Node *def = use->in(k); 1981 if (!def) 1982 continue; 1983 1984 uint l = _node_latency[def->_idx] + use->latency(k); 1985 if (latency < l) 1986 latency = l; 1987 } 1988 1989 _node_latency[use->_idx] = latency; 1990 1991#ifndef PRODUCT 1992 if (_cfg->C->trace_opto_output()) { 1993 tty->print("# latency %4d: ", latency); 1994 use->dump(); 1995 } 1996#endif 1997 } 1998 1999#ifndef PRODUCT 2000 if (_cfg->C->trace_opto_output()) 2001 tty->print("# <- ComputeLocalLatenciesForward\n"); 2002#endif 2003 2004} // end ComputeLocalLatenciesForward 2005 2006// See if this node fits into the present instruction bundle 2007bool Scheduling::NodeFitsInBundle(Node *n) { 2008 uint n_idx = n->_idx; 2009 2010 // If this is the unconditional delay instruction, then it fits 2011 if (n == _unconditional_delay_slot) { 2012#ifndef PRODUCT 2013 if (_cfg->C->trace_opto_output()) 2014 tty->print("# NodeFitsInBundle [%4d]: TRUE; is in unconditional delay slot\n", n->_idx); 2015#endif 2016 return (true); 2017 } 2018 2019 // If the node cannot be scheduled this cycle, skip it 2020 if (_current_latency[n_idx] > _bundle_cycle_number) { 2021#ifndef PRODUCT 2022 if (_cfg->C->trace_opto_output()) 2023 tty->print("# NodeFitsInBundle [%4d]: FALSE; latency %4d > %d\n", 2024 n->_idx, _current_latency[n_idx], _bundle_cycle_number); 2025#endif 2026 return (false); 2027 } 2028 2029 const Pipeline *node_pipeline = n->pipeline(); 2030 2031 uint instruction_count = node_pipeline->instructionCount(); 2032 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0) 2033 instruction_count = 0; 2034 else if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot) 2035 instruction_count++; 2036 2037 if (_bundle_instr_count + instruction_count > Pipeline::_max_instrs_per_cycle) { 2038#ifndef PRODUCT 2039 if (_cfg->C->trace_opto_output()) 2040 tty->print("# NodeFitsInBundle [%4d]: FALSE; too many instructions: %d > %d\n", 2041 n->_idx, _bundle_instr_count + instruction_count, Pipeline::_max_instrs_per_cycle); 2042#endif 2043 return (false); 2044 } 2045 2046 // Don't allow non-machine nodes to be handled this way 2047 if (!n->is_Mach() && instruction_count == 0) 2048 return (false); 2049 2050 // See if there is any overlap 2051 uint delay = _bundle_use.full_latency(0, node_pipeline->resourceUse()); 2052 2053 if (delay > 0) { 2054#ifndef PRODUCT 2055 if (_cfg->C->trace_opto_output()) 2056 tty->print("# NodeFitsInBundle [%4d]: FALSE; functional units overlap\n", n_idx); 2057#endif 2058 return false; 2059 } 2060 2061#ifndef PRODUCT 2062 if (_cfg->C->trace_opto_output()) 2063 tty->print("# NodeFitsInBundle [%4d]: TRUE\n", n_idx); 2064#endif 2065 2066 return true; 2067} 2068 2069Node * Scheduling::ChooseNodeToBundle() { 2070 uint siz = _available.size(); 2071 2072 if (siz == 0) { 2073 2074#ifndef PRODUCT 2075 if (_cfg->C->trace_opto_output()) 2076 tty->print("# ChooseNodeToBundle: NULL\n"); 2077#endif 2078 return (NULL); 2079 } 2080 2081 // Fast path, if only 1 instruction in the bundle 2082 if (siz == 1) { 2083#ifndef PRODUCT 2084 if (_cfg->C->trace_opto_output()) { 2085 tty->print("# ChooseNodeToBundle (only 1): "); 2086 _available[0]->dump(); 2087 } 2088#endif 2089 return (_available[0]); 2090 } 2091 2092 // Don't bother, if the bundle is already full 2093 if (_bundle_instr_count < Pipeline::_max_instrs_per_cycle) { 2094 for ( uint i = 0; i < siz; i++ ) { 2095 Node *n = _available[i]; 2096 2097 // Skip projections, we'll handle them another way 2098 if (n->is_Proj()) 2099 continue; 2100 2101 // This presupposed that instructions are inserted into the 2102 // available list in a legality order; i.e. instructions that 2103 // must be inserted first are at the head of the list 2104 if (NodeFitsInBundle(n)) { 2105#ifndef PRODUCT 2106 if (_cfg->C->trace_opto_output()) { 2107 tty->print("# ChooseNodeToBundle: "); 2108 n->dump(); 2109 } 2110#endif 2111 return (n); 2112 } 2113 } 2114 } 2115 2116 // Nothing fits in this bundle, choose the highest priority 2117#ifndef PRODUCT 2118 if (_cfg->C->trace_opto_output()) { 2119 tty->print("# ChooseNodeToBundle: "); 2120 _available[0]->dump(); 2121 } 2122#endif 2123 2124 return _available[0]; 2125} 2126 2127//------------------------------AddNodeToAvailableList------------------------- 2128void Scheduling::AddNodeToAvailableList(Node *n) { 2129 assert( !n->is_Proj(), "projections never directly made available" ); 2130#ifndef PRODUCT 2131 if (_cfg->C->trace_opto_output()) { 2132 tty->print("# AddNodeToAvailableList: "); 2133 n->dump(); 2134 } 2135#endif 2136 2137 int latency = _current_latency[n->_idx]; 2138 2139 // Insert in latency order (insertion sort) 2140 uint i; 2141 for ( i=0; i < _available.size(); i++ ) 2142 if (_current_latency[_available[i]->_idx] > latency) 2143 break; 2144 2145 // Special Check for compares following branches 2146 if( n->is_Mach() && _scheduled.size() > 0 ) { 2147 int op = n->as_Mach()->ideal_Opcode(); 2148 Node *last = _scheduled[0]; 2149 if( last->is_MachIf() && last->in(1) == n && 2150 ( op == Op_CmpI || 2151 op == Op_CmpU || 2152 op == Op_CmpP || 2153 op == Op_CmpF || 2154 op == Op_CmpD || 2155 op == Op_CmpL ) ) { 2156 2157 // Recalculate position, moving to front of same latency 2158 for ( i=0 ; i < _available.size(); i++ ) 2159 if (_current_latency[_available[i]->_idx] >= latency) 2160 break; 2161 } 2162 } 2163 2164 // Insert the node in the available list 2165 _available.insert(i, n); 2166 2167#ifndef PRODUCT 2168 if (_cfg->C->trace_opto_output()) 2169 dump_available(); 2170#endif 2171} 2172 2173//------------------------------DecrementUseCounts----------------------------- 2174void Scheduling::DecrementUseCounts(Node *n, const Block *bb) { 2175 for ( uint i=0; i < n->len(); i++ ) { 2176 Node *def = n->in(i); 2177 if (!def) continue; 2178 if( def->is_Proj() ) // If this is a machine projection, then 2179 def = def->in(0); // propagate usage thru to the base instruction 2180 2181 if( _bbs[def->_idx] != bb ) // Ignore if not block-local 2182 continue; 2183 2184 // Compute the latency 2185 uint l = _bundle_cycle_number + n->latency(i); 2186 if (_current_latency[def->_idx] < l) 2187 _current_latency[def->_idx] = l; 2188 2189 // If this does not have uses then schedule it 2190 if ((--_uses[def->_idx]) == 0) 2191 AddNodeToAvailableList(def); 2192 } 2193} 2194 2195//------------------------------AddNodeToBundle-------------------------------- 2196void Scheduling::AddNodeToBundle(Node *n, const Block *bb) { 2197#ifndef PRODUCT 2198 if (_cfg->C->trace_opto_output()) { 2199 tty->print("# AddNodeToBundle: "); 2200 n->dump(); 2201 } 2202#endif 2203 2204 // Remove this from the available list 2205 uint i; 2206 for (i = 0; i < _available.size(); i++) 2207 if (_available[i] == n) 2208 break; 2209 assert(i < _available.size(), "entry in _available list not found"); 2210 _available.remove(i); 2211 2212 // See if this fits in the current bundle 2213 const Pipeline *node_pipeline = n->pipeline(); 2214 const Pipeline_Use& node_usage = node_pipeline->resourceUse(); 2215 2216 // Check for instructions to be placed in the delay slot. We 2217 // do this before we actually schedule the current instruction, 2218 // because the delay slot follows the current instruction. 2219 if (Pipeline::_branch_has_delay_slot && 2220 node_pipeline->hasBranchDelay() && 2221 !_unconditional_delay_slot) { 2222 2223 uint siz = _available.size(); 2224 2225 // Conditional branches can support an instruction that 2226 // is unconditionally executed and not dependent by the 2227 // branch, OR a conditionally executed instruction if 2228 // the branch is taken. In practice, this means that 2229 // the first instruction at the branch target is 2230 // copied to the delay slot, and the branch goes to 2231 // the instruction after that at the branch target 2232 if ( n->is_Mach() && n->is_Branch() ) { 2233 2234 assert( !n->is_MachNullCheck(), "should not look for delay slot for Null Check" ); 2235 assert( !n->is_Catch(), "should not look for delay slot for Catch" ); 2236 2237#ifndef PRODUCT 2238 _branches++; 2239#endif 2240 2241 // At least 1 instruction is on the available list 2242 // that is not dependent on the branch 2243 for (uint i = 0; i < siz; i++) { 2244 Node *d = _available[i]; 2245 const Pipeline *avail_pipeline = d->pipeline(); 2246 2247 // Don't allow safepoints in the branch shadow, that will 2248 // cause a number of difficulties 2249 if ( avail_pipeline->instructionCount() == 1 && 2250 !avail_pipeline->hasMultipleBundles() && 2251 !avail_pipeline->hasBranchDelay() && 2252 Pipeline::instr_has_unit_size() && 2253 d->size(_regalloc) == Pipeline::instr_unit_size() && 2254 NodeFitsInBundle(d) && 2255 !node_bundling(d)->used_in_delay()) { 2256 2257 if (d->is_Mach() && !d->is_MachSafePoint()) { 2258 // A node that fits in the delay slot was found, so we need to 2259 // set the appropriate bits in the bundle pipeline information so 2260 // that it correctly indicates resource usage. Later, when we 2261 // attempt to add this instruction to the bundle, we will skip 2262 // setting the resource usage. 2263 _unconditional_delay_slot = d; 2264 node_bundling(n)->set_use_unconditional_delay(); 2265 node_bundling(d)->set_used_in_unconditional_delay(); 2266 _bundle_use.add_usage(avail_pipeline->resourceUse()); 2267 _current_latency[d->_idx] = _bundle_cycle_number; 2268 _next_node = d; 2269 ++_bundle_instr_count; 2270#ifndef PRODUCT 2271 _unconditional_delays++; 2272#endif 2273 break; 2274 } 2275 } 2276 } 2277 } 2278 2279 // No delay slot, add a nop to the usage 2280 if (!_unconditional_delay_slot) { 2281 // See if adding an instruction in the delay slot will overflow 2282 // the bundle. 2283 if (!NodeFitsInBundle(_nop)) { 2284#ifndef PRODUCT 2285 if (_cfg->C->trace_opto_output()) 2286 tty->print("# *** STEP(1 instruction for delay slot) ***\n"); 2287#endif 2288 step(1); 2289 } 2290 2291 _bundle_use.add_usage(_nop->pipeline()->resourceUse()); 2292 _next_node = _nop; 2293 ++_bundle_instr_count; 2294 } 2295 2296 // See if the instruction in the delay slot requires a 2297 // step of the bundles 2298 if (!NodeFitsInBundle(n)) { 2299#ifndef PRODUCT 2300 if (_cfg->C->trace_opto_output()) 2301 tty->print("# *** STEP(branch won't fit) ***\n"); 2302#endif 2303 // Update the state information 2304 _bundle_instr_count = 0; 2305 _bundle_cycle_number += 1; 2306 _bundle_use.step(1); 2307 } 2308 } 2309 2310 // Get the number of instructions 2311 uint instruction_count = node_pipeline->instructionCount(); 2312 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0) 2313 instruction_count = 0; 2314 2315 // Compute the latency information 2316 uint delay = 0; 2317 2318 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) { 2319 int relative_latency = _current_latency[n->_idx] - _bundle_cycle_number; 2320 if (relative_latency < 0) 2321 relative_latency = 0; 2322 2323 delay = _bundle_use.full_latency(relative_latency, node_usage); 2324 2325 // Does not fit in this bundle, start a new one 2326 if (delay > 0) { 2327 step(delay); 2328 2329#ifndef PRODUCT 2330 if (_cfg->C->trace_opto_output()) 2331 tty->print("# *** STEP(%d) ***\n", delay); 2332#endif 2333 } 2334 } 2335 2336 // If this was placed in the delay slot, ignore it 2337 if (n != _unconditional_delay_slot) { 2338 2339 if (delay == 0) { 2340 if (node_pipeline->hasMultipleBundles()) { 2341#ifndef PRODUCT 2342 if (_cfg->C->trace_opto_output()) 2343 tty->print("# *** STEP(multiple instructions) ***\n"); 2344#endif 2345 step(1); 2346 } 2347 2348 else if (instruction_count + _bundle_instr_count > Pipeline::_max_instrs_per_cycle) { 2349#ifndef PRODUCT 2350 if (_cfg->C->trace_opto_output()) 2351 tty->print("# *** STEP(%d >= %d instructions) ***\n", 2352 instruction_count + _bundle_instr_count, 2353 Pipeline::_max_instrs_per_cycle); 2354#endif 2355 step(1); 2356 } 2357 } 2358 2359 if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot) 2360 _bundle_instr_count++; 2361 2362 // Set the node's latency 2363 _current_latency[n->_idx] = _bundle_cycle_number; 2364 2365 // Now merge the functional unit information 2366 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) 2367 _bundle_use.add_usage(node_usage); 2368 2369 // Increment the number of instructions in this bundle 2370 _bundle_instr_count += instruction_count; 2371 2372 // Remember this node for later 2373 if (n->is_Mach()) 2374 _next_node = n; 2375 } 2376 2377 // It's possible to have a BoxLock in the graph and in the _bbs mapping but 2378 // not in the bb->_nodes array. This happens for debug-info-only BoxLocks. 2379 // 'Schedule' them (basically ignore in the schedule) but do not insert them 2380 // into the block. All other scheduled nodes get put in the schedule here. 2381 int op = n->Opcode(); 2382 if( (op == Op_Node && n->req() == 0) || // anti-dependence node OR 2383 (op != Op_Node && // Not an unused antidepedence node and 2384 // not an unallocated boxlock 2385 (OptoReg::is_valid(_regalloc->get_reg_first(n)) || op != Op_BoxLock)) ) { 2386 2387 // Push any trailing projections 2388 if( bb->_nodes[bb->_nodes.size()-1] != n ) { 2389 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2390 Node *foi = n->fast_out(i); 2391 if( foi->is_Proj() ) 2392 _scheduled.push(foi); 2393 } 2394 } 2395 2396 // Put the instruction in the schedule list 2397 _scheduled.push(n); 2398 } 2399 2400#ifndef PRODUCT 2401 if (_cfg->C->trace_opto_output()) 2402 dump_available(); 2403#endif 2404 2405 // Walk all the definitions, decrementing use counts, and 2406 // if a definition has a 0 use count, place it in the available list. 2407 DecrementUseCounts(n,bb); 2408} 2409 2410//------------------------------ComputeUseCount-------------------------------- 2411// This method sets the use count within a basic block. We will ignore all 2412// uses outside the current basic block. As we are doing a backwards walk, 2413// any node we reach that has a use count of 0 may be scheduled. This also 2414// avoids the problem of cyclic references from phi nodes, as long as phi 2415// nodes are at the front of the basic block. This method also initializes 2416// the available list to the set of instructions that have no uses within this 2417// basic block. 2418void Scheduling::ComputeUseCount(const Block *bb) { 2419#ifndef PRODUCT 2420 if (_cfg->C->trace_opto_output()) 2421 tty->print("# -> ComputeUseCount\n"); 2422#endif 2423 2424 // Clear the list of available and scheduled instructions, just in case 2425 _available.clear(); 2426 _scheduled.clear(); 2427 2428 // No delay slot specified 2429 _unconditional_delay_slot = NULL; 2430 2431#ifdef ASSERT 2432 for( uint i=0; i < bb->_nodes.size(); i++ ) 2433 assert( _uses[bb->_nodes[i]->_idx] == 0, "_use array not clean" ); 2434#endif 2435 2436 // Force the _uses count to never go to zero for unscheduable pieces 2437 // of the block 2438 for( uint k = 0; k < _bb_start; k++ ) 2439 _uses[bb->_nodes[k]->_idx] = 1; 2440 for( uint l = _bb_end; l < bb->_nodes.size(); l++ ) 2441 _uses[bb->_nodes[l]->_idx] = 1; 2442 2443 // Iterate backwards over the instructions in the block. Don't count the 2444 // branch projections at end or the block header instructions. 2445 for( uint j = _bb_end-1; j >= _bb_start; j-- ) { 2446 Node *n = bb->_nodes[j]; 2447 if( n->is_Proj() ) continue; // Projections handled another way 2448 2449 // Account for all uses 2450 for ( uint k = 0; k < n->len(); k++ ) { 2451 Node *inp = n->in(k); 2452 if (!inp) continue; 2453 assert(inp != n, "no cycles allowed" ); 2454 if( _bbs[inp->_idx] == bb ) { // Block-local use? 2455 if( inp->is_Proj() ) // Skip through Proj's 2456 inp = inp->in(0); 2457 ++_uses[inp->_idx]; // Count 1 block-local use 2458 } 2459 } 2460 2461 // If this instruction has a 0 use count, then it is available 2462 if (!_uses[n->_idx]) { 2463 _current_latency[n->_idx] = _bundle_cycle_number; 2464 AddNodeToAvailableList(n); 2465 } 2466 2467#ifndef PRODUCT 2468 if (_cfg->C->trace_opto_output()) { 2469 tty->print("# uses: %3d: ", _uses[n->_idx]); 2470 n->dump(); 2471 } 2472#endif 2473 } 2474 2475#ifndef PRODUCT 2476 if (_cfg->C->trace_opto_output()) 2477 tty->print("# <- ComputeUseCount\n"); 2478#endif 2479} 2480 2481// This routine performs scheduling on each basic block in reverse order, 2482// using instruction latencies and taking into account function unit 2483// availability. 2484void Scheduling::DoScheduling() { 2485#ifndef PRODUCT 2486 if (_cfg->C->trace_opto_output()) 2487 tty->print("# -> DoScheduling\n"); 2488#endif 2489 2490 Block *succ_bb = NULL; 2491 Block *bb; 2492 2493 // Walk over all the basic blocks in reverse order 2494 for( int i=_cfg->_num_blocks-1; i >= 0; succ_bb = bb, i-- ) { 2495 bb = _cfg->_blocks[i]; 2496 2497#ifndef PRODUCT 2498 if (_cfg->C->trace_opto_output()) { 2499 tty->print("# Schedule BB#%03d (initial)\n", i); 2500 for (uint j = 0; j < bb->_nodes.size(); j++) 2501 bb->_nodes[j]->dump(); 2502 } 2503#endif 2504 2505 // On the head node, skip processing 2506 if( bb == _cfg->_broot ) 2507 continue; 2508 2509 // Skip empty, connector blocks 2510 if (bb->is_connector()) 2511 continue; 2512 2513 // If the following block is not the sole successor of 2514 // this one, then reset the pipeline information 2515 if (bb->_num_succs != 1 || bb->non_connector_successor(0) != succ_bb) { 2516#ifndef PRODUCT 2517 if (_cfg->C->trace_opto_output()) { 2518 tty->print("*** bundle start of next BB, node %d, for %d instructions\n", 2519 _next_node->_idx, _bundle_instr_count); 2520 } 2521#endif 2522 step_and_clear(); 2523 } 2524 2525 // Leave untouched the starting instruction, any Phis, a CreateEx node 2526 // or Top. bb->_nodes[_bb_start] is the first schedulable instruction. 2527 _bb_end = bb->_nodes.size()-1; 2528 for( _bb_start=1; _bb_start <= _bb_end; _bb_start++ ) { 2529 Node *n = bb->_nodes[_bb_start]; 2530 // Things not matched, like Phinodes and ProjNodes don't get scheduled. 2531 // Also, MachIdealNodes do not get scheduled 2532 if( !n->is_Mach() ) continue; // Skip non-machine nodes 2533 MachNode *mach = n->as_Mach(); 2534 int iop = mach->ideal_Opcode(); 2535 if( iop == Op_CreateEx ) continue; // CreateEx is pinned 2536 if( iop == Op_Con ) continue; // Do not schedule Top 2537 if( iop == Op_Node && // Do not schedule PhiNodes, ProjNodes 2538 mach->pipeline() == MachNode::pipeline_class() && 2539 !n->is_SpillCopy() ) // Breakpoints, Prolog, etc 2540 continue; 2541 break; // Funny loop structure to be sure... 2542 } 2543 // Compute last "interesting" instruction in block - last instruction we 2544 // might schedule. _bb_end points just after last schedulable inst. We 2545 // normally schedule conditional branches (despite them being forced last 2546 // in the block), because they have delay slots we can fill. Calls all 2547 // have their delay slots filled in the template expansions, so we don't 2548 // bother scheduling them. 2549 Node *last = bb->_nodes[_bb_end]; 2550 // Ignore trailing NOPs. 2551 while (_bb_end > 0 && last->is_Mach() && 2552 last->as_Mach()->ideal_Opcode() == Op_Con) { 2553 last = bb->_nodes[--_bb_end]; 2554 } 2555 assert(!last->is_Mach() || last->as_Mach()->ideal_Opcode() != Op_Con, ""); 2556 if( last->is_Catch() || 2557 // Exclude unreachable path case when Halt node is in a separate block. 2558 (_bb_end > 1 && last->is_Mach() && last->as_Mach()->ideal_Opcode() == Op_Halt) ) { 2559 // There must be a prior call. Skip it. 2560 while( !bb->_nodes[--_bb_end]->is_MachCall() ) { 2561 assert( bb->_nodes[_bb_end]->is_MachProj(), "skipping projections after expected call" ); 2562 } 2563 } else if( last->is_MachNullCheck() ) { 2564 // Backup so the last null-checked memory instruction is 2565 // outside the schedulable range. Skip over the nullcheck, 2566 // projection, and the memory nodes. 2567 Node *mem = last->in(1); 2568 do { 2569 _bb_end--; 2570 } while (mem != bb->_nodes[_bb_end]); 2571 } else { 2572 // Set _bb_end to point after last schedulable inst. 2573 _bb_end++; 2574 } 2575 2576 assert( _bb_start <= _bb_end, "inverted block ends" ); 2577 2578 // Compute the register antidependencies for the basic block 2579 ComputeRegisterAntidependencies(bb); 2580 if (_cfg->C->failing()) return; // too many D-U pinch points 2581 2582 // Compute intra-bb latencies for the nodes 2583 ComputeLocalLatenciesForward(bb); 2584 2585 // Compute the usage within the block, and set the list of all nodes 2586 // in the block that have no uses within the block. 2587 ComputeUseCount(bb); 2588 2589 // Schedule the remaining instructions in the block 2590 while ( _available.size() > 0 ) { 2591 Node *n = ChooseNodeToBundle(); 2592 AddNodeToBundle(n,bb); 2593 } 2594 2595 assert( _scheduled.size() == _bb_end - _bb_start, "wrong number of instructions" ); 2596#ifdef ASSERT 2597 for( uint l = _bb_start; l < _bb_end; l++ ) { 2598 Node *n = bb->_nodes[l]; 2599 uint m; 2600 for( m = 0; m < _bb_end-_bb_start; m++ ) 2601 if( _scheduled[m] == n ) 2602 break; 2603 assert( m < _bb_end-_bb_start, "instruction missing in schedule" ); 2604 } 2605#endif 2606 2607 // Now copy the instructions (in reverse order) back to the block 2608 for ( uint k = _bb_start; k < _bb_end; k++ ) 2609 bb->_nodes.map(k, _scheduled[_bb_end-k-1]); 2610 2611#ifndef PRODUCT 2612 if (_cfg->C->trace_opto_output()) { 2613 tty->print("# Schedule BB#%03d (final)\n", i); 2614 uint current = 0; 2615 for (uint j = 0; j < bb->_nodes.size(); j++) { 2616 Node *n = bb->_nodes[j]; 2617 if( valid_bundle_info(n) ) { 2618 Bundle *bundle = node_bundling(n); 2619 if (bundle->instr_count() > 0 || bundle->flags() > 0) { 2620 tty->print("*** Bundle: "); 2621 bundle->dump(); 2622 } 2623 n->dump(); 2624 } 2625 } 2626 } 2627#endif 2628#ifdef ASSERT 2629 verify_good_schedule(bb,"after block local scheduling"); 2630#endif 2631 } 2632 2633#ifndef PRODUCT 2634 if (_cfg->C->trace_opto_output()) 2635 tty->print("# <- DoScheduling\n"); 2636#endif 2637 2638 // Record final node-bundling array location 2639 _regalloc->C->set_node_bundling_base(_node_bundling_base); 2640 2641} // end DoScheduling 2642 2643//------------------------------verify_good_schedule--------------------------- 2644// Verify that no live-range used in the block is killed in the block by a 2645// wrong DEF. This doesn't verify live-ranges that span blocks. 2646 2647// Check for edge existence. Used to avoid adding redundant precedence edges. 2648static bool edge_from_to( Node *from, Node *to ) { 2649 for( uint i=0; i<from->len(); i++ ) 2650 if( from->in(i) == to ) 2651 return true; 2652 return false; 2653} 2654 2655#ifdef ASSERT 2656//------------------------------verify_do_def---------------------------------- 2657void Scheduling::verify_do_def( Node *n, OptoReg::Name def, const char *msg ) { 2658 // Check for bad kills 2659 if( OptoReg::is_valid(def) ) { // Ignore stores & control flow 2660 Node *prior_use = _reg_node[def]; 2661 if( prior_use && !edge_from_to(prior_use,n) ) { 2662 tty->print("%s = ",OptoReg::as_VMReg(def)->name()); 2663 n->dump(); 2664 tty->print_cr("..."); 2665 prior_use->dump(); 2666 assert(edge_from_to(prior_use,n),msg); 2667 } 2668 _reg_node.map(def,NULL); // Kill live USEs 2669 } 2670} 2671 2672//------------------------------verify_good_schedule--------------------------- 2673void Scheduling::verify_good_schedule( Block *b, const char *msg ) { 2674 2675 // Zap to something reasonable for the verify code 2676 _reg_node.clear(); 2677 2678 // Walk over the block backwards. Check to make sure each DEF doesn't 2679 // kill a live value (other than the one it's supposed to). Add each 2680 // USE to the live set. 2681 for( uint i = b->_nodes.size()-1; i >= _bb_start; i-- ) { 2682 Node *n = b->_nodes[i]; 2683 int n_op = n->Opcode(); 2684 if( n_op == Op_MachProj && n->ideal_reg() == MachProjNode::fat_proj ) { 2685 // Fat-proj kills a slew of registers 2686 RegMask rm = n->out_RegMask();// Make local copy 2687 while( rm.is_NotEmpty() ) { 2688 OptoReg::Name kill = rm.find_first_elem(); 2689 rm.Remove(kill); 2690 verify_do_def( n, kill, msg ); 2691 } 2692 } else if( n_op != Op_Node ) { // Avoid brand new antidependence nodes 2693 // Get DEF'd registers the normal way 2694 verify_do_def( n, _regalloc->get_reg_first(n), msg ); 2695 verify_do_def( n, _regalloc->get_reg_second(n), msg ); 2696 } 2697 2698 // Now make all USEs live 2699 for( uint i=1; i<n->req(); i++ ) { 2700 Node *def = n->in(i); 2701 assert(def != 0, "input edge required"); 2702 OptoReg::Name reg_lo = _regalloc->get_reg_first(def); 2703 OptoReg::Name reg_hi = _regalloc->get_reg_second(def); 2704 if( OptoReg::is_valid(reg_lo) ) { 2705 assert(!_reg_node[reg_lo] || edge_from_to(_reg_node[reg_lo],def), msg); 2706 _reg_node.map(reg_lo,n); 2707 } 2708 if( OptoReg::is_valid(reg_hi) ) { 2709 assert(!_reg_node[reg_hi] || edge_from_to(_reg_node[reg_hi],def), msg); 2710 _reg_node.map(reg_hi,n); 2711 } 2712 } 2713 2714 } 2715 2716 // Zap to something reasonable for the Antidependence code 2717 _reg_node.clear(); 2718} 2719#endif 2720 2721// Conditionally add precedence edges. Avoid putting edges on Projs. 2722static void add_prec_edge_from_to( Node *from, Node *to ) { 2723 if( from->is_Proj() ) { // Put precedence edge on Proj's input 2724 assert( from->req() == 1 && (from->len() == 1 || from->in(1)==0), "no precedence edges on projections" ); 2725 from = from->in(0); 2726 } 2727 if( from != to && // No cycles (for things like LD L0,[L0+4] ) 2728 !edge_from_to( from, to ) ) // Avoid duplicate edge 2729 from->add_prec(to); 2730} 2731 2732//------------------------------anti_do_def------------------------------------ 2733void Scheduling::anti_do_def( Block *b, Node *def, OptoReg::Name def_reg, int is_def ) { 2734 if( !OptoReg::is_valid(def_reg) ) // Ignore stores & control flow 2735 return; 2736 2737 Node *pinch = _reg_node[def_reg]; // Get pinch point 2738 if( !pinch || _bbs[pinch->_idx] != b || // No pinch-point yet? 2739 is_def ) { // Check for a true def (not a kill) 2740 _reg_node.map(def_reg,def); // Record def/kill as the optimistic pinch-point 2741 return; 2742 } 2743 2744 Node *kill = def; // Rename 'def' to more descriptive 'kill' 2745 debug_only( def = (Node*)0xdeadbeef; ) 2746 2747 // After some number of kills there _may_ be a later def 2748 Node *later_def = NULL; 2749 2750 // Finding a kill requires a real pinch-point. 2751 // Check for not already having a pinch-point. 2752 // Pinch points are Op_Node's. 2753 if( pinch->Opcode() != Op_Node ) { // Or later-def/kill as pinch-point? 2754 later_def = pinch; // Must be def/kill as optimistic pinch-point 2755 if ( _pinch_free_list.size() > 0) { 2756 pinch = _pinch_free_list.pop(); 2757 } else { 2758 pinch = new (_cfg->C, 1) Node(1); // Pinch point to-be 2759 } 2760 if (pinch->_idx >= _regalloc->node_regs_max_index()) { 2761 _cfg->C->record_method_not_compilable("too many D-U pinch points"); 2762 return; 2763 } 2764 _bbs.map(pinch->_idx,b); // Pretend it's valid in this block (lazy init) 2765 _reg_node.map(def_reg,pinch); // Record pinch-point 2766 //_regalloc->set_bad(pinch->_idx); // Already initialized this way. 2767 if( later_def->outcnt() == 0 || later_def->ideal_reg() == MachProjNode::fat_proj ) { // Distinguish def from kill 2768 pinch->init_req(0, _cfg->C->top()); // set not NULL for the next call 2769 add_prec_edge_from_to(later_def,pinch); // Add edge from kill to pinch 2770 later_def = NULL; // and no later def 2771 } 2772 pinch->set_req(0,later_def); // Hook later def so we can find it 2773 } else { // Else have valid pinch point 2774 if( pinch->in(0) ) // If there is a later-def 2775 later_def = pinch->in(0); // Get it 2776 } 2777 2778 // Add output-dependence edge from later def to kill 2779 if( later_def ) // If there is some original def 2780 add_prec_edge_from_to(later_def,kill); // Add edge from def to kill 2781 2782 // See if current kill is also a use, and so is forced to be the pinch-point. 2783 if( pinch->Opcode() == Op_Node ) { 2784 Node *uses = kill->is_Proj() ? kill->in(0) : kill; 2785 for( uint i=1; i<uses->req(); i++ ) { 2786 if( _regalloc->get_reg_first(uses->in(i)) == def_reg || 2787 _regalloc->get_reg_second(uses->in(i)) == def_reg ) { 2788 // Yes, found a use/kill pinch-point 2789 pinch->set_req(0,NULL); // 2790 pinch->replace_by(kill); // Move anti-dep edges up 2791 pinch = kill; 2792 _reg_node.map(def_reg,pinch); 2793 return; 2794 } 2795 } 2796 } 2797 2798 // Add edge from kill to pinch-point 2799 add_prec_edge_from_to(kill,pinch); 2800} 2801 2802//------------------------------anti_do_use------------------------------------ 2803void Scheduling::anti_do_use( Block *b, Node *use, OptoReg::Name use_reg ) { 2804 if( !OptoReg::is_valid(use_reg) ) // Ignore stores & control flow 2805 return; 2806 Node *pinch = _reg_node[use_reg]; // Get pinch point 2807 // Check for no later def_reg/kill in block 2808 if( pinch && _bbs[pinch->_idx] == b && 2809 // Use has to be block-local as well 2810 _bbs[use->_idx] == b ) { 2811 if( pinch->Opcode() == Op_Node && // Real pinch-point (not optimistic?) 2812 pinch->req() == 1 ) { // pinch not yet in block? 2813 pinch->del_req(0); // yank pointer to later-def, also set flag 2814 // Insert the pinch-point in the block just after the last use 2815 b->_nodes.insert(b->find_node(use)+1,pinch); 2816 _bb_end++; // Increase size scheduled region in block 2817 } 2818 2819 add_prec_edge_from_to(pinch,use); 2820 } 2821} 2822 2823//------------------------------ComputeRegisterAntidependences----------------- 2824// We insert antidependences between the reads and following write of 2825// allocated registers to prevent illegal code motion. Hopefully, the 2826// number of added references should be fairly small, especially as we 2827// are only adding references within the current basic block. 2828void Scheduling::ComputeRegisterAntidependencies(Block *b) { 2829 2830#ifdef ASSERT 2831 verify_good_schedule(b,"before block local scheduling"); 2832#endif 2833 2834 // A valid schedule, for each register independently, is an endless cycle 2835 // of: a def, then some uses (connected to the def by true dependencies), 2836 // then some kills (defs with no uses), finally the cycle repeats with a new 2837 // def. The uses are allowed to float relative to each other, as are the 2838 // kills. No use is allowed to slide past a kill (or def). This requires 2839 // antidependencies between all uses of a single def and all kills that 2840 // follow, up to the next def. More edges are redundant, because later defs 2841 // & kills are already serialized with true or antidependencies. To keep 2842 // the edge count down, we add a 'pinch point' node if there's more than 2843 // one use or more than one kill/def. 2844 2845 // We add dependencies in one bottom-up pass. 2846 2847 // For each instruction we handle it's DEFs/KILLs, then it's USEs. 2848 2849 // For each DEF/KILL, we check to see if there's a prior DEF/KILL for this 2850 // register. If not, we record the DEF/KILL in _reg_node, the 2851 // register-to-def mapping. If there is a prior DEF/KILL, we insert a 2852 // "pinch point", a new Node that's in the graph but not in the block. 2853 // We put edges from the prior and current DEF/KILLs to the pinch point. 2854 // We put the pinch point in _reg_node. If there's already a pinch point 2855 // we merely add an edge from the current DEF/KILL to the pinch point. 2856 2857 // After doing the DEF/KILLs, we handle USEs. For each used register, we 2858 // put an edge from the pinch point to the USE. 2859 2860 // To be expedient, the _reg_node array is pre-allocated for the whole 2861 // compilation. _reg_node is lazily initialized; it either contains a NULL, 2862 // or a valid def/kill/pinch-point, or a leftover node from some prior 2863 // block. Leftover node from some prior block is treated like a NULL (no 2864 // prior def, so no anti-dependence needed). Valid def is distinguished by 2865 // it being in the current block. 2866 bool fat_proj_seen = false; 2867 uint last_safept = _bb_end-1; 2868 Node* end_node = (_bb_end-1 >= _bb_start) ? b->_nodes[last_safept] : NULL; 2869 Node* last_safept_node = end_node; 2870 for( uint i = _bb_end-1; i >= _bb_start; i-- ) { 2871 Node *n = b->_nodes[i]; 2872 int is_def = n->outcnt(); // def if some uses prior to adding precedence edges 2873 if( n->is_MachProj() && n->ideal_reg() == MachProjNode::fat_proj ) { 2874 // Fat-proj kills a slew of registers 2875 // This can add edges to 'n' and obscure whether or not it was a def, 2876 // hence the is_def flag. 2877 fat_proj_seen = true; 2878 RegMask rm = n->out_RegMask();// Make local copy 2879 while( rm.is_NotEmpty() ) { 2880 OptoReg::Name kill = rm.find_first_elem(); 2881 rm.Remove(kill); 2882 anti_do_def( b, n, kill, is_def ); 2883 } 2884 } else { 2885 // Get DEF'd registers the normal way 2886 anti_do_def( b, n, _regalloc->get_reg_first(n), is_def ); 2887 anti_do_def( b, n, _regalloc->get_reg_second(n), is_def ); 2888 } 2889 2890 // Kill projections on a branch should appear to occur on the 2891 // branch, not afterwards, so grab the masks from the projections 2892 // and process them. 2893 if (n->is_Branch()) { 2894 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2895 Node* use = n->fast_out(i); 2896 if (use->is_Proj()) { 2897 RegMask rm = use->out_RegMask();// Make local copy 2898 while( rm.is_NotEmpty() ) { 2899 OptoReg::Name kill = rm.find_first_elem(); 2900 rm.Remove(kill); 2901 anti_do_def( b, n, kill, false ); 2902 } 2903 } 2904 } 2905 } 2906 2907 // Check each register used by this instruction for a following DEF/KILL 2908 // that must occur afterward and requires an anti-dependence edge. 2909 for( uint j=0; j<n->req(); j++ ) { 2910 Node *def = n->in(j); 2911 if( def ) { 2912 assert( !def->is_MachProj() || def->ideal_reg() != MachProjNode::fat_proj, "" ); 2913 anti_do_use( b, n, _regalloc->get_reg_first(def) ); 2914 anti_do_use( b, n, _regalloc->get_reg_second(def) ); 2915 } 2916 } 2917 // Do not allow defs of new derived values to float above GC 2918 // points unless the base is definitely available at the GC point. 2919 2920 Node *m = b->_nodes[i]; 2921 2922 // Add precedence edge from following safepoint to use of derived pointer 2923 if( last_safept_node != end_node && 2924 m != last_safept_node) { 2925 for (uint k = 1; k < m->req(); k++) { 2926 const Type *t = m->in(k)->bottom_type(); 2927 if( t->isa_oop_ptr() && 2928 t->is_ptr()->offset() != 0 ) { 2929 last_safept_node->add_prec( m ); 2930 break; 2931 } 2932 } 2933 } 2934 2935 if( n->jvms() ) { // Precedence edge from derived to safept 2936 // Check if last_safept_node was moved by pinch-point insertion in anti_do_use() 2937 if( b->_nodes[last_safept] != last_safept_node ) { 2938 last_safept = b->find_node(last_safept_node); 2939 } 2940 for( uint j=last_safept; j > i; j-- ) { 2941 Node *mach = b->_nodes[j]; 2942 if( mach->is_Mach() && mach->as_Mach()->ideal_Opcode() == Op_AddP ) 2943 mach->add_prec( n ); 2944 } 2945 last_safept = i; 2946 last_safept_node = m; 2947 } 2948 } 2949 2950 if (fat_proj_seen) { 2951 // Garbage collect pinch nodes that were not consumed. 2952 // They are usually created by a fat kill MachProj for a call. 2953 garbage_collect_pinch_nodes(); 2954 } 2955} 2956 2957//------------------------------garbage_collect_pinch_nodes------------------------------- 2958 2959// Garbage collect pinch nodes for reuse by other blocks. 2960// 2961// The block scheduler's insertion of anti-dependence 2962// edges creates many pinch nodes when the block contains 2963// 2 or more Calls. A pinch node is used to prevent a 2964// combinatorial explosion of edges. If a set of kills for a 2965// register is anti-dependent on a set of uses (or defs), rather 2966// than adding an edge in the graph between each pair of kill 2967// and use (or def), a pinch is inserted between them: 2968// 2969// use1 use2 use3 2970// \ | / 2971// \ | / 2972// pinch 2973// / | \ 2974// / | \ 2975// kill1 kill2 kill3 2976// 2977// One pinch node is created per register killed when 2978// the second call is encountered during a backwards pass 2979// over the block. Most of these pinch nodes are never 2980// wired into the graph because the register is never 2981// used or def'ed in the block. 2982// 2983void Scheduling::garbage_collect_pinch_nodes() { 2984#ifndef PRODUCT 2985 if (_cfg->C->trace_opto_output()) tty->print("Reclaimed pinch nodes:"); 2986#endif 2987 int trace_cnt = 0; 2988 for (uint k = 0; k < _reg_node.Size(); k++) { 2989 Node* pinch = _reg_node[k]; 2990 if (pinch != NULL && pinch->Opcode() == Op_Node && 2991 // no predecence input edges 2992 (pinch->req() == pinch->len() || pinch->in(pinch->req()) == NULL) ) { 2993 cleanup_pinch(pinch); 2994 _pinch_free_list.push(pinch); 2995 _reg_node.map(k, NULL); 2996#ifndef PRODUCT 2997 if (_cfg->C->trace_opto_output()) { 2998 trace_cnt++; 2999 if (trace_cnt > 40) { 3000 tty->print("\n"); 3001 trace_cnt = 0; 3002 } 3003 tty->print(" %d", pinch->_idx); 3004 } 3005#endif 3006 } 3007 } 3008#ifndef PRODUCT 3009 if (_cfg->C->trace_opto_output()) tty->print("\n"); 3010#endif 3011} 3012 3013// Clean up a pinch node for reuse. 3014void Scheduling::cleanup_pinch( Node *pinch ) { 3015 assert (pinch && pinch->Opcode() == Op_Node && pinch->req() == 1, "just checking"); 3016 3017 for (DUIterator_Last imin, i = pinch->last_outs(imin); i >= imin; ) { 3018 Node* use = pinch->last_out(i); 3019 uint uses_found = 0; 3020 for (uint j = use->req(); j < use->len(); j++) { 3021 if (use->in(j) == pinch) { 3022 use->rm_prec(j); 3023 uses_found++; 3024 } 3025 } 3026 assert(uses_found > 0, "must be a precedence edge"); 3027 i -= uses_found; // we deleted 1 or more copies of this edge 3028 } 3029 // May have a later_def entry 3030 pinch->set_req(0, NULL); 3031} 3032 3033//------------------------------print_statistics------------------------------- 3034#ifndef PRODUCT 3035 3036void Scheduling::dump_available() const { 3037 tty->print("#Availist "); 3038 for (uint i = 0; i < _available.size(); i++) 3039 tty->print(" N%d/l%d", _available[i]->_idx,_current_latency[_available[i]->_idx]); 3040 tty->cr(); 3041} 3042 3043// Print Scheduling Statistics 3044void Scheduling::print_statistics() { 3045 // Print the size added by nops for bundling 3046 tty->print("Nops added %d bytes to total of %d bytes", 3047 _total_nop_size, _total_method_size); 3048 if (_total_method_size > 0) 3049 tty->print(", for %.2f%%", 3050 ((double)_total_nop_size) / ((double) _total_method_size) * 100.0); 3051 tty->print("\n"); 3052 3053 // Print the number of branch shadows filled 3054 if (Pipeline::_branch_has_delay_slot) { 3055 tty->print("Of %d branches, %d had unconditional delay slots filled", 3056 _total_branches, _total_unconditional_delays); 3057 if (_total_branches > 0) 3058 tty->print(", for %.2f%%", 3059 ((double)_total_unconditional_delays) / ((double)_total_branches) * 100.0); 3060 tty->print("\n"); 3061 } 3062 3063 uint total_instructions = 0, total_bundles = 0; 3064 3065 for (uint i = 1; i <= Pipeline::_max_instrs_per_cycle; i++) { 3066 uint bundle_count = _total_instructions_per_bundle[i]; 3067 total_instructions += bundle_count * i; 3068 total_bundles += bundle_count; 3069 } 3070 3071 if (total_bundles > 0) 3072 tty->print("Average ILP (excluding nops) is %.2f\n", 3073 ((double)total_instructions) / ((double)total_bundles)); 3074} 3075#endif 3076