1 /*
2 * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "incls/_precompiled.incl"
26 #include "incls/_output.cpp.incl"
27
28 extern uint size_java_to_interp();
29 extern uint reloc_java_to_interp();
30 extern uint size_exception_handler();
31 extern uint size_deopt_handler();
32
33 #ifndef PRODUCT
34 #define DEBUG_ARG(x) , x
35 #else
36 #define DEBUG_ARG(x)
37 #endif
38
39 extern int emit_exception_handler(CodeBuffer &cbuf);
40 extern int emit_deopt_handler(CodeBuffer &cbuf);
41
42 //------------------------------Output-----------------------------------------
43 // Convert Nodes to instruction bits and pass off to the VM
44 void Compile::Output() {
45 // RootNode goes
46 assert( _cfg->_broot->_nodes.size() == 0, "" );
47
48 // The number of new nodes (mostly MachNop) is proportional to
49 // the number of java calls and inner loops which are aligned.
50 if ( C->check_node_count((NodeLimitFudgeFactor + C->java_calls()*3 +
51 C->inner_loops()*(OptoLoopAlignment-1)),
52 "out of nodes before code generation" ) ) {
53 return;
54 }
55 // Make sure I can find the Start Node
56 Block_Array& bbs = _cfg->_bbs;
57 Block *entry = _cfg->_blocks[1];
58 Block *broot = _cfg->_broot;
59
60 const StartNode *start = entry->_nodes[0]->as_Start();
61
62 // Replace StartNode with prolog
63 MachPrologNode *prolog = new (this) MachPrologNode();
64 entry->_nodes.map( 0, prolog );
65 bbs.map( prolog->_idx, entry );
66 bbs.map( start->_idx, NULL ); // start is no longer in any block
67
68 // Virtual methods need an unverified entry point
69
70 if( is_osr_compilation() ) {
71 if( PoisonOSREntry ) {
72 // TODO: Should use a ShouldNotReachHereNode...
73 _cfg->insert( broot, 0, new (this) MachBreakpointNode() );
74 }
75 } else {
76 if( _method && !_method->flags().is_static() ) {
77 // Insert unvalidated entry point
78 _cfg->insert( broot, 0, new (this) MachUEPNode() );
79 }
80
81 }
82
83
84 // Break before main entry point
85 if( (_method && _method->break_at_execute())
86 #ifndef PRODUCT
87 ||(OptoBreakpoint && is_method_compilation())
88 ||(OptoBreakpointOSR && is_osr_compilation())
89 ||(OptoBreakpointC2R && !_method)
90 #endif
91 ) {
92 // checking for _method means that OptoBreakpoint does not apply to
93 // runtime stubs or frame converters
94 _cfg->insert( entry, 1, new (this) MachBreakpointNode() );
95 }
96
97 // Insert epilogs before every return
98 for( uint i=0; i<_cfg->_num_blocks; i++ ) {
99 Block *b = _cfg->_blocks[i];
100 if( !b->is_connector() && b->non_connector_successor(0) == _cfg->_broot ) { // Found a program exit point?
101 Node *m = b->end();
102 if( m->is_Mach() && m->as_Mach()->ideal_Opcode() != Op_Halt ) {
103 MachEpilogNode *epilog = new (this) MachEpilogNode(m->as_Mach()->ideal_Opcode() == Op_Return);
104 b->add_inst( epilog );
105 bbs.map(epilog->_idx, b);
106 //_regalloc->set_bad(epilog->_idx); // Already initialized this way.
107 }
108 }
109 }
110
111 # ifdef ENABLE_ZAP_DEAD_LOCALS
112 if ( ZapDeadCompiledLocals ) Insert_zap_nodes();
113 # endif
114
115 ScheduleAndBundle();
116
117 #ifndef PRODUCT
118 if (trace_opto_output()) {
119 tty->print("\n---- After ScheduleAndBundle ----\n");
120 for (uint i = 0; i < _cfg->_num_blocks; i++) {
121 tty->print("\nBB#%03d:\n", i);
122 Block *bb = _cfg->_blocks[i];
123 for (uint j = 0; j < bb->_nodes.size(); j++) {
124 Node *n = bb->_nodes[j];
125 OptoReg::Name reg = _regalloc->get_reg_first(n);
126 tty->print(" %-6s ", reg >= 0 && reg < REG_COUNT ? Matcher::regName[reg] : "");
127 n->dump();
128 }
129 }
130 }
131 #endif
132
133 if (failing()) return;
134
135 BuildOopMaps();
136
137 if (failing()) return;
138
139 Fill_buffer();
140 }
141
142 bool Compile::need_stack_bang(int frame_size_in_bytes) const {
143 // Determine if we need to generate a stack overflow check.
144 // Do it if the method is not a stub function and
145 // has java calls or has frame size > vm_page_size/8.
146 return (stub_function() == NULL &&
147 (has_java_calls() || frame_size_in_bytes > os::vm_page_size()>>3));
148 }
149
150 bool Compile::need_register_stack_bang() const {
151 // Determine if we need to generate a register stack overflow check.
152 // This is only used on architectures which have split register
153 // and memory stacks (ie. IA64).
154 // Bang if the method is not a stub function and has java calls
155 return (stub_function() == NULL && has_java_calls());
156 }
157
158 # ifdef ENABLE_ZAP_DEAD_LOCALS
159
160
161 // In order to catch compiler oop-map bugs, we have implemented
162 // a debugging mode called ZapDeadCompilerLocals.
163 // This mode causes the compiler to insert a call to a runtime routine,
164 // "zap_dead_locals", right before each place in compiled code
165 // that could potentially be a gc-point (i.e., a safepoint or oop map point).
166 // The runtime routine checks that locations mapped as oops are really
167 // oops, that locations mapped as values do not look like oops,
168 // and that locations mapped as dead are not used later
169 // (by zapping them to an invalid address).
170
171 int Compile::_CompiledZap_count = 0;
172
173 void Compile::Insert_zap_nodes() {
174 bool skip = false;
175
176
177 // Dink with static counts because code code without the extra
178 // runtime calls is MUCH faster for debugging purposes
179
180 if ( CompileZapFirst == 0 ) ; // nothing special
181 else if ( CompileZapFirst > CompiledZap_count() ) skip = true;
182 else if ( CompileZapFirst == CompiledZap_count() )
183 warning("starting zap compilation after skipping");
184
185 if ( CompileZapLast == -1 ) ; // nothing special
186 else if ( CompileZapLast < CompiledZap_count() ) skip = true;
187 else if ( CompileZapLast == CompiledZap_count() )
188 warning("about to compile last zap");
189
190 ++_CompiledZap_count; // counts skipped zaps, too
191
192 if ( skip ) return;
193
194
195 if ( _method == NULL )
196 return; // no safepoints/oopmaps emitted for calls in stubs,so we don't care
197
198 // Insert call to zap runtime stub before every node with an oop map
199 for( uint i=0; i<_cfg->_num_blocks; i++ ) {
200 Block *b = _cfg->_blocks[i];
201 for ( uint j = 0; j < b->_nodes.size(); ++j ) {
202 Node *n = b->_nodes[j];
203
204 // Determining if we should insert a zap-a-lot node in output.
205 // We do that for all nodes that has oopmap info, except for calls
206 // to allocation. Calls to allocation passes in the old top-of-eden pointer
207 // and expect the C code to reset it. Hence, there can be no safepoints between
208 // the inlined-allocation and the call to new_Java, etc.
209 // We also cannot zap monitor calls, as they must hold the microlock
210 // during the call to Zap, which also wants to grab the microlock.
211 bool insert = n->is_MachSafePoint() && (n->as_MachSafePoint()->oop_map() != NULL);
212 if ( insert ) { // it is MachSafePoint
213 if ( !n->is_MachCall() ) {
214 insert = false;
215 } else if ( n->is_MachCall() ) {
216 MachCallNode* call = n->as_MachCall();
217 if (call->entry_point() == OptoRuntime::new_instance_Java() ||
218 call->entry_point() == OptoRuntime::new_array_Java() ||
219 call->entry_point() == OptoRuntime::multianewarray2_Java() ||
220 call->entry_point() == OptoRuntime::multianewarray3_Java() ||
221 call->entry_point() == OptoRuntime::multianewarray4_Java() ||
222 call->entry_point() == OptoRuntime::multianewarray5_Java() ||
223 call->entry_point() == OptoRuntime::slow_arraycopy_Java() ||
224 call->entry_point() == OptoRuntime::complete_monitor_locking_Java()
225 ) {
226 insert = false;
227 }
228 }
229 if (insert) {
230 Node *zap = call_zap_node(n->as_MachSafePoint(), i);
231 b->_nodes.insert( j, zap );
232 _cfg->_bbs.map( zap->_idx, b );
233 ++j;
234 }
235 }
236 }
237 }
238 }
239
240
241 Node* Compile::call_zap_node(MachSafePointNode* node_to_check, int block_no) {
242 const TypeFunc *tf = OptoRuntime::zap_dead_locals_Type();
243 CallStaticJavaNode* ideal_node =
244 new (this, tf->domain()->cnt()) CallStaticJavaNode( tf,
245 OptoRuntime::zap_dead_locals_stub(_method->flags().is_native()),
246 "call zap dead locals stub", 0, TypePtr::BOTTOM);
247 // We need to copy the OopMap from the site we're zapping at.
248 // We have to make a copy, because the zap site might not be
249 // a call site, and zap_dead is a call site.
250 OopMap* clone = node_to_check->oop_map()->deep_copy();
251
252 // Add the cloned OopMap to the zap node
253 ideal_node->set_oop_map(clone);
254 return _matcher->match_sfpt(ideal_node);
255 }
256
257 //------------------------------is_node_getting_a_safepoint--------------------
258 bool Compile::is_node_getting_a_safepoint( Node* n) {
259 // This code duplicates the logic prior to the call of add_safepoint
260 // below in this file.
261 if( n->is_MachSafePoint() ) return true;
262 return false;
263 }
264
265 # endif // ENABLE_ZAP_DEAD_LOCALS
266
267 //------------------------------compute_loop_first_inst_sizes------------------
268 // Compute the size of first NumberOfLoopInstrToAlign instructions at the top
269 // of a loop. When aligning a loop we need to provide enough instructions
270 // in cpu's fetch buffer to feed decoders. The loop alignment could be
271 // avoided if we have enough instructions in fetch buffer at the head of a loop.
272 // By default, the size is set to 999999 by Block's constructor so that
273 // a loop will be aligned if the size is not reset here.
274 //
275 // Note: Mach instructions could contain several HW instructions
276 // so the size is estimated only.
277 //
278 void Compile::compute_loop_first_inst_sizes() {
279 // The next condition is used to gate the loop alignment optimization.
280 // Don't aligned a loop if there are enough instructions at the head of a loop
281 // or alignment padding is larger then MaxLoopPad. By default, MaxLoopPad
282 // is equal to OptoLoopAlignment-1 except on new Intel cpus, where it is
283 // equal to 11 bytes which is the largest address NOP instruction.
284 if( MaxLoopPad < OptoLoopAlignment-1 ) {
285 uint last_block = _cfg->_num_blocks-1;
286 for( uint i=1; i <= last_block; i++ ) {
287 Block *b = _cfg->_blocks[i];
288 // Check the first loop's block which requires an alignment.
289 if( b->loop_alignment() > (uint)relocInfo::addr_unit() ) {
290 uint sum_size = 0;
291 uint inst_cnt = NumberOfLoopInstrToAlign;
292 inst_cnt = b->compute_first_inst_size(sum_size, inst_cnt, _regalloc);
293
294 // Check subsequent fallthrough blocks if the loop's first
295 // block(s) does not have enough instructions.
296 Block *nb = b;
297 while( inst_cnt > 0 &&
298 i < last_block &&
299 !_cfg->_blocks[i+1]->has_loop_alignment() &&
300 !nb->has_successor(b) ) {
301 i++;
302 nb = _cfg->_blocks[i];
303 inst_cnt = nb->compute_first_inst_size(sum_size, inst_cnt, _regalloc);
304 } // while( inst_cnt > 0 && i < last_block )
305
306 b->set_first_inst_size(sum_size);
307 } // f( b->head()->is_Loop() )
308 } // for( i <= last_block )
309 } // if( MaxLoopPad < OptoLoopAlignment-1 )
310 }
311
312 //----------------------Shorten_branches---------------------------------------
313 // The architecture description provides short branch variants for some long
314 // branch instructions. Replace eligible long branches with short branches.
315 void Compile::Shorten_branches(Label *labels, int& code_size, int& reloc_size, int& stub_size) {
316
317 // fill in the nop array for bundling computations
318 MachNode *_nop_list[Bundle::_nop_count];
319 Bundle::initialize_nops(_nop_list, this);
320
321 // ------------------
322 // Compute size of each block, method size, and relocation information size
323 uint *jmp_end = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks);
324 uint *blk_starts = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks+1);
325 DEBUG_ONLY( uint *jmp_target = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks); )
326 DEBUG_ONLY( uint *jmp_rule = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks); )
327 blk_starts[0] = 0;
328
329 // Initialize the sizes to 0
330 code_size = 0; // Size in bytes of generated code
331 stub_size = 0; // Size in bytes of all stub entries
332 // Size in bytes of all relocation entries, including those in local stubs.
333 // Start with 2-bytes of reloc info for the unvalidated entry point
334 reloc_size = 1; // Number of relocation entries
335
336 // Make three passes. The first computes pessimistic blk_starts,
337 // relative jmp_end and reloc_size information. The second performs
338 // short branch substitution using the pessimistic sizing. The
339 // third inserts nops where needed.
340
341 Node *nj; // tmp
342
343 // Step one, perform a pessimistic sizing pass.
344 uint i;
345 uint min_offset_from_last_call = 1; // init to a positive value
346 uint nop_size = (new (this) MachNopNode())->size(_regalloc);
347 for( i=0; i<_cfg->_num_blocks; i++ ) { // For all blocks
348 Block *b = _cfg->_blocks[i];
349
350 // Sum all instruction sizes to compute block size
351 uint last_inst = b->_nodes.size();
352 uint blk_size = 0;
353 for( uint j = 0; j<last_inst; j++ ) {
354 nj = b->_nodes[j];
355 uint inst_size = nj->size(_regalloc);
356 blk_size += inst_size;
357 // Handle machine instruction nodes
358 if( nj->is_Mach() ) {
359 MachNode *mach = nj->as_Mach();
360 blk_size += (mach->alignment_required() - 1) * relocInfo::addr_unit(); // assume worst case padding
361 reloc_size += mach->reloc();
362 if( mach->is_MachCall() ) {
363 MachCallNode *mcall = mach->as_MachCall();
364 // This destination address is NOT PC-relative
365
366 mcall->method_set((intptr_t)mcall->entry_point());
367
368 if( mcall->is_MachCallJava() && mcall->as_MachCallJava()->_method ) {
369 stub_size += size_java_to_interp();
370 reloc_size += reloc_java_to_interp();
371 }
372 } else if (mach->is_MachSafePoint()) {
373 // If call/safepoint are adjacent, account for possible
374 // nop to disambiguate the two safepoints.
375 if (min_offset_from_last_call == 0) {
376 blk_size += nop_size;
377 }
378 }
379 }
380 min_offset_from_last_call += inst_size;
381 // Remember end of call offset
382 if (nj->is_MachCall() && nj->as_MachCall()->is_safepoint_node()) {
383 min_offset_from_last_call = 0;
384 }
385 }
386
387 // During short branch replacement, we store the relative (to blk_starts)
388 // end of jump in jmp_end, rather than the absolute end of jump. This
389 // is so that we do not need to recompute sizes of all nodes when we compute
390 // correct blk_starts in our next sizing pass.
391 jmp_end[i] = blk_size;
392 DEBUG_ONLY( jmp_target[i] = 0; )
393
394 // When the next block starts a loop, we may insert pad NOP
395 // instructions. Since we cannot know our future alignment,
396 // assume the worst.
397 if( i<_cfg->_num_blocks-1 ) {
398 Block *nb = _cfg->_blocks[i+1];
399 int max_loop_pad = nb->code_alignment()-relocInfo::addr_unit();
400 if( max_loop_pad > 0 ) {
401 assert(is_power_of_2(max_loop_pad+relocInfo::addr_unit()), "");
402 blk_size += max_loop_pad;
403 }
404 }
405
406 // Save block size; update total method size
407 blk_starts[i+1] = blk_starts[i]+blk_size;
408 }
409
410 // Step two, replace eligible long jumps.
411
412 // Note: this will only get the long branches within short branch
413 // range. Another pass might detect more branches that became
414 // candidates because the shortening in the first pass exposed
415 // more opportunities. Unfortunately, this would require
416 // recomputing the starting and ending positions for the blocks
417 for( i=0; i<_cfg->_num_blocks; i++ ) {
418 Block *b = _cfg->_blocks[i];
419
420 int j;
421 // Find the branch; ignore trailing NOPs.
422 for( j = b->_nodes.size()-1; j>=0; j-- ) {
423 nj = b->_nodes[j];
424 if( !nj->is_Mach() || nj->as_Mach()->ideal_Opcode() != Op_Con )
425 break;
426 }
427
428 if (j >= 0) {
429 if( nj->is_Mach() && nj->as_Mach()->may_be_short_branch() ) {
430 MachNode *mach = nj->as_Mach();
431 // This requires the TRUE branch target be in succs[0]
432 uint bnum = b->non_connector_successor(0)->_pre_order;
433 uintptr_t target = blk_starts[bnum];
434 if( mach->is_pc_relative() ) {
435 int offset = target-(blk_starts[i] + jmp_end[i]);
436 if (_matcher->is_short_branch_offset(mach->rule(), offset)) {
437 // We've got a winner. Replace this branch.
438 MachNode* replacement = mach->short_branch_version(this);
439 b->_nodes.map(j, replacement);
440 mach->subsume_by(replacement);
441
442 // Update the jmp_end size to save time in our
443 // next pass.
444 jmp_end[i] -= (mach->size(_regalloc) - replacement->size(_regalloc));
445 DEBUG_ONLY( jmp_target[i] = bnum; );
446 DEBUG_ONLY( jmp_rule[i] = mach->rule(); );
447 }
448 } else {
449 #ifndef PRODUCT
450 mach->dump(3);
451 #endif
452 Unimplemented();
453 }
454 }
455 }
456 }
457
458 // Compute the size of first NumberOfLoopInstrToAlign instructions at head
459 // of a loop. It is used to determine the padding for loop alignment.
460 compute_loop_first_inst_sizes();
461
462 // Step 3, compute the offsets of all the labels
463 uint last_call_adr = max_uint;
464 for( i=0; i<_cfg->_num_blocks; i++ ) { // For all blocks
465 // copy the offset of the beginning to the corresponding label
466 assert(labels[i].is_unused(), "cannot patch at this point");
467 labels[i].bind_loc(blk_starts[i], CodeBuffer::SECT_INSTS);
468
469 // insert padding for any instructions that need it
470 Block *b = _cfg->_blocks[i];
471 uint last_inst = b->_nodes.size();
472 uint adr = blk_starts[i];
473 for( uint j = 0; j<last_inst; j++ ) {
474 nj = b->_nodes[j];
475 if( nj->is_Mach() ) {
476 int padding = nj->as_Mach()->compute_padding(adr);
477 // If call/safepoint are adjacent insert a nop (5010568)
478 if (padding == 0 && nj->is_MachSafePoint() && !nj->is_MachCall() &&
479 adr == last_call_adr ) {
480 padding = nop_size;
481 }
482 if(padding > 0) {
483 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size");
484 int nops_cnt = padding / nop_size;
485 MachNode *nop = new (this) MachNopNode(nops_cnt);
486 b->_nodes.insert(j++, nop);
487 _cfg->_bbs.map( nop->_idx, b );
488 adr += padding;
489 last_inst++;
490 }
491 }
492 adr += nj->size(_regalloc);
493
494 // Remember end of call offset
495 if (nj->is_MachCall() && nj->as_MachCall()->is_safepoint_node()) {
496 last_call_adr = adr;
497 }
498 }
499
500 if ( i != _cfg->_num_blocks-1) {
501 // Get the size of the block
502 uint blk_size = adr - blk_starts[i];
503
504 // When the next block is the top of a loop, we may insert pad NOP
505 // instructions.
506 Block *nb = _cfg->_blocks[i+1];
507 int current_offset = blk_starts[i] + blk_size;
508 current_offset += nb->alignment_padding(current_offset);
509 // Save block size; update total method size
510 blk_starts[i+1] = current_offset;
511 }
512 }
513
514 #ifdef ASSERT
515 for( i=0; i<_cfg->_num_blocks; i++ ) { // For all blocks
516 if( jmp_target[i] != 0 ) {
517 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_end[i]);
518 if (!_matcher->is_short_branch_offset(jmp_rule[i], offset)) {
519 tty->print_cr("target (%d) - jmp_end(%d) = offset (%d), jmp_block B%d, target_block B%d", blk_starts[jmp_target[i]], blk_starts[i] + jmp_end[i], offset, i, jmp_target[i]);
520 }
521 assert(_matcher->is_short_branch_offset(jmp_rule[i], offset), "Displacement too large for short jmp");
522 }
523 }
524 #endif
525
526 // ------------------
527 // Compute size for code buffer
528 code_size = blk_starts[i-1] + jmp_end[i-1];
529
530 // Relocation records
531 reloc_size += 1; // Relo entry for exception handler
532
533 // Adjust reloc_size to number of record of relocation info
534 // Min is 2 bytes, max is probably 6 or 8, with a tax up to 25% for
535 // a relocation index.
536 // The CodeBuffer will expand the locs array if this estimate is too low.
537 reloc_size *= 10 / sizeof(relocInfo);
538 }
539
540 //------------------------------FillLocArray-----------------------------------
541 // Create a bit of debug info and append it to the array. The mapping is from
542 // Java local or expression stack to constant, register or stack-slot. For
543 // doubles, insert 2 mappings and return 1 (to tell the caller that the next
544 // entry has been taken care of and caller should skip it).
545 static LocationValue *new_loc_value( PhaseRegAlloc *ra, OptoReg::Name regnum, Location::Type l_type ) {
546 // This should never have accepted Bad before
547 assert(OptoReg::is_valid(regnum), "location must be valid");
548 return (OptoReg::is_reg(regnum))
549 ? new LocationValue(Location::new_reg_loc(l_type, OptoReg::as_VMReg(regnum)) )
550 : new LocationValue(Location::new_stk_loc(l_type, ra->reg2offset(regnum)));
551 }
552
553
554 ObjectValue*
555 Compile::sv_for_node_id(GrowableArray<ScopeValue*> *objs, int id) {
556 for (int i = 0; i < objs->length(); i++) {
557 assert(objs->at(i)->is_object(), "corrupt object cache");
558 ObjectValue* sv = (ObjectValue*) objs->at(i);
559 if (sv->id() == id) {
560 return sv;
561 }
562 }
563 // Otherwise..
564 return NULL;
565 }
566
567 void Compile::set_sv_for_object_node(GrowableArray<ScopeValue*> *objs,
568 ObjectValue* sv ) {
569 assert(sv_for_node_id(objs, sv->id()) == NULL, "Precondition");
570 objs->append(sv);
571 }
572
573
574 void Compile::FillLocArray( int idx, MachSafePointNode* sfpt, Node *local,
575 GrowableArray<ScopeValue*> *array,
576 GrowableArray<ScopeValue*> *objs ) {
577 assert( local, "use _top instead of null" );
578 if (array->length() != idx) {
579 assert(array->length() == idx + 1, "Unexpected array count");
580 // Old functionality:
581 // return
582 // New functionality:
583 // Assert if the local is not top. In product mode let the new node
584 // override the old entry.
585 assert(local == top(), "LocArray collision");
586 if (local == top()) {
587 return;
588 }
589 array->pop();
590 }
591 const Type *t = local->bottom_type();
592
593 // Is it a safepoint scalar object node?
594 if (local->is_SafePointScalarObject()) {
595 SafePointScalarObjectNode* spobj = local->as_SafePointScalarObject();
596
597 ObjectValue* sv = Compile::sv_for_node_id(objs, spobj->_idx);
598 if (sv == NULL) {
599 ciKlass* cik = t->is_oopptr()->klass();
600 assert(cik->is_instance_klass() ||
601 cik->is_array_klass(), "Not supported allocation.");
602 sv = new ObjectValue(spobj->_idx,
603 new ConstantOopWriteValue(cik->constant_encoding()));
604 Compile::set_sv_for_object_node(objs, sv);
605
606 uint first_ind = spobj->first_index();
607 for (uint i = 0; i < spobj->n_fields(); i++) {
608 Node* fld_node = sfpt->in(first_ind+i);
609 (void)FillLocArray(sv->field_values()->length(), sfpt, fld_node, sv->field_values(), objs);
610 }
611 }
612 array->append(sv);
613 return;
614 }
615
616 // Grab the register number for the local
617 OptoReg::Name regnum = _regalloc->get_reg_first(local);
618 if( OptoReg::is_valid(regnum) ) {// Got a register/stack?
619 // Record the double as two float registers.
620 // The register mask for such a value always specifies two adjacent
621 // float registers, with the lower register number even.
622 // Normally, the allocation of high and low words to these registers
623 // is irrelevant, because nearly all operations on register pairs
624 // (e.g., StoreD) treat them as a single unit.
625 // Here, we assume in addition that the words in these two registers
626 // stored "naturally" (by operations like StoreD and double stores
627 // within the interpreter) such that the lower-numbered register
628 // is written to the lower memory address. This may seem like
629 // a machine dependency, but it is not--it is a requirement on
630 // the author of the <arch>.ad file to ensure that, for every
631 // even/odd double-register pair to which a double may be allocated,
632 // the word in the even single-register is stored to the first
633 // memory word. (Note that register numbers are completely
634 // arbitrary, and are not tied to any machine-level encodings.)
635 #ifdef _LP64
636 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon ) {
637 array->append(new ConstantIntValue(0));
638 array->append(new_loc_value( _regalloc, regnum, Location::dbl ));
639 } else if ( t->base() == Type::Long ) {
640 array->append(new ConstantIntValue(0));
641 array->append(new_loc_value( _regalloc, regnum, Location::lng ));
642 } else if ( t->base() == Type::RawPtr ) {
643 // jsr/ret return address which must be restored into a the full
644 // width 64-bit stack slot.
645 array->append(new_loc_value( _regalloc, regnum, Location::lng ));
646 }
647 #else //_LP64
648 #ifdef SPARC
649 if (t->base() == Type::Long && OptoReg::is_reg(regnum)) {
650 // For SPARC we have to swap high and low words for
651 // long values stored in a single-register (g0-g7).
652 array->append(new_loc_value( _regalloc, regnum , Location::normal ));
653 array->append(new_loc_value( _regalloc, OptoReg::add(regnum,1), Location::normal ));
654 } else
655 #endif //SPARC
656 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon || t->base() == Type::Long ) {
657 // Repack the double/long as two jints.
658 // The convention the interpreter uses is that the second local
659 // holds the first raw word of the native double representation.
660 // This is actually reasonable, since locals and stack arrays
661 // grow downwards in all implementations.
662 // (If, on some machine, the interpreter's Java locals or stack
663 // were to grow upwards, the embedded doubles would be word-swapped.)
664 array->append(new_loc_value( _regalloc, OptoReg::add(regnum,1), Location::normal ));
665 array->append(new_loc_value( _regalloc, regnum , Location::normal ));
666 }
667 #endif //_LP64
668 else if( (t->base() == Type::FloatBot || t->base() == Type::FloatCon) &&
669 OptoReg::is_reg(regnum) ) {
670 array->append(new_loc_value( _regalloc, regnum, Matcher::float_in_double()
671 ? Location::float_in_dbl : Location::normal ));
672 } else if( t->base() == Type::Int && OptoReg::is_reg(regnum) ) {
673 array->append(new_loc_value( _regalloc, regnum, Matcher::int_in_long
674 ? Location::int_in_long : Location::normal ));
675 } else if( t->base() == Type::NarrowOop ) {
676 array->append(new_loc_value( _regalloc, regnum, Location::narrowoop ));
677 } else {
678 array->append(new_loc_value( _regalloc, regnum, _regalloc->is_oop(local) ? Location::oop : Location::normal ));
679 }
680 return;
681 }
682
683 // No register. It must be constant data.
684 switch (t->base()) {
685 case Type::Half: // Second half of a double
686 ShouldNotReachHere(); // Caller should skip 2nd halves
687 break;
688 case Type::AnyPtr:
689 array->append(new ConstantOopWriteValue(NULL));
690 break;
691 case Type::AryPtr:
692 case Type::InstPtr:
693 case Type::KlassPtr: // fall through
694 array->append(new ConstantOopWriteValue(t->isa_oopptr()->const_oop()->constant_encoding()));
695 break;
696 case Type::NarrowOop:
697 if (t == TypeNarrowOop::NULL_PTR) {
698 array->append(new ConstantOopWriteValue(NULL));
699 } else {
700 array->append(new ConstantOopWriteValue(t->make_ptr()->isa_oopptr()->const_oop()->constant_encoding()));
701 }
702 break;
703 case Type::Int:
704 array->append(new ConstantIntValue(t->is_int()->get_con()));
705 break;
706 case Type::RawPtr:
707 // A return address (T_ADDRESS).
708 assert((intptr_t)t->is_ptr()->get_con() < (intptr_t)0x10000, "must be a valid BCI");
709 #ifdef _LP64
710 // Must be restored to the full-width 64-bit stack slot.
711 array->append(new ConstantLongValue(t->is_ptr()->get_con()));
712 #else
713 array->append(new ConstantIntValue(t->is_ptr()->get_con()));
714 #endif
715 break;
716 case Type::FloatCon: {
717 float f = t->is_float_constant()->getf();
718 array->append(new ConstantIntValue(jint_cast(f)));
719 break;
720 }
721 case Type::DoubleCon: {
722 jdouble d = t->is_double_constant()->getd();
723 #ifdef _LP64
724 array->append(new ConstantIntValue(0));
725 array->append(new ConstantDoubleValue(d));
726 #else
727 // Repack the double as two jints.
728 // The convention the interpreter uses is that the second local
729 // holds the first raw word of the native double representation.
730 // This is actually reasonable, since locals and stack arrays
731 // grow downwards in all implementations.
732 // (If, on some machine, the interpreter's Java locals or stack
733 // were to grow upwards, the embedded doubles would be word-swapped.)
734 jint *dp = (jint*)&d;
735 array->append(new ConstantIntValue(dp[1]));
736 array->append(new ConstantIntValue(dp[0]));
737 #endif
738 break;
739 }
740 case Type::Long: {
741 jlong d = t->is_long()->get_con();
742 #ifdef _LP64
743 array->append(new ConstantIntValue(0));
744 array->append(new ConstantLongValue(d));
745 #else
746 // Repack the long as two jints.
747 // The convention the interpreter uses is that the second local
748 // holds the first raw word of the native double representation.
749 // This is actually reasonable, since locals and stack arrays
750 // grow downwards in all implementations.
751 // (If, on some machine, the interpreter's Java locals or stack
752 // were to grow upwards, the embedded doubles would be word-swapped.)
753 jint *dp = (jint*)&d;
754 array->append(new ConstantIntValue(dp[1]));
755 array->append(new ConstantIntValue(dp[0]));
756 #endif
757 break;
758 }
759 case Type::Top: // Add an illegal value here
760 array->append(new LocationValue(Location()));
761 break;
762 default:
763 ShouldNotReachHere();
764 break;
765 }
766 }
767
768 // Determine if this node starts a bundle
769 bool Compile::starts_bundle(const Node *n) const {
770 return (_node_bundling_limit > n->_idx &&
771 _node_bundling_base[n->_idx].starts_bundle());
772 }
773
774 //--------------------------Process_OopMap_Node--------------------------------
775 void Compile::Process_OopMap_Node(MachNode *mach, int current_offset) {
776
777 // Handle special safepoint nodes for synchronization
778 MachSafePointNode *sfn = mach->as_MachSafePoint();
779 MachCallNode *mcall;
780
781 #ifdef ENABLE_ZAP_DEAD_LOCALS
782 assert( is_node_getting_a_safepoint(mach), "logic does not match; false negative");
783 #endif
784
785 int safepoint_pc_offset = current_offset;
786 bool is_method_handle_invoke = false;
787 bool return_oop = false;
788
789 // Add the safepoint in the DebugInfoRecorder
790 if( !mach->is_MachCall() ) {
791 mcall = NULL;
792 debug_info()->add_safepoint(safepoint_pc_offset, sfn->_oop_map);
793 } else {
794 mcall = mach->as_MachCall();
795
796 // Is the call a MethodHandle call?
797 if (mcall->is_MachCallJava()) {
798 if (mcall->as_MachCallJava()->_method_handle_invoke) {
799 assert(has_method_handle_invokes(), "must have been set during call generation");
800 is_method_handle_invoke = true;
801 }
802 }
803
804 // Check if a call returns an object.
805 if (mcall->return_value_is_used() &&
806 mcall->tf()->range()->field_at(TypeFunc::Parms)->isa_ptr()) {
807 return_oop = true;
808 }
809 safepoint_pc_offset += mcall->ret_addr_offset();
810 debug_info()->add_safepoint(safepoint_pc_offset, mcall->_oop_map);
811 }
812
813 // Loop over the JVMState list to add scope information
814 // Do not skip safepoints with a NULL method, they need monitor info
815 JVMState* youngest_jvms = sfn->jvms();
816 int max_depth = youngest_jvms->depth();
817
818 // Allocate the object pool for scalar-replaced objects -- the map from
819 // small-integer keys (which can be recorded in the local and ostack
820 // arrays) to descriptions of the object state.
821 GrowableArray<ScopeValue*> *objs = new GrowableArray<ScopeValue*>();
822
823 // Visit scopes from oldest to youngest.
824 for (int depth = 1; depth <= max_depth; depth++) {
825 JVMState* jvms = youngest_jvms->of_depth(depth);
826 int idx;
827 ciMethod* method = jvms->has_method() ? jvms->method() : NULL;
828 // Safepoints that do not have method() set only provide oop-map and monitor info
829 // to support GC; these do not support deoptimization.
830 int num_locs = (method == NULL) ? 0 : jvms->loc_size();
831 int num_exps = (method == NULL) ? 0 : jvms->stk_size();
832 int num_mon = jvms->nof_monitors();
833 assert(method == NULL || jvms->bci() < 0 || num_locs == method->max_locals(),
834 "JVMS local count must match that of the method");
835
836 // Add Local and Expression Stack Information
837
838 // Insert locals into the locarray
839 GrowableArray<ScopeValue*> *locarray = new GrowableArray<ScopeValue*>(num_locs);
840 for( idx = 0; idx < num_locs; idx++ ) {
841 FillLocArray( idx, sfn, sfn->local(jvms, idx), locarray, objs );
842 }
843
844 // Insert expression stack entries into the exparray
845 GrowableArray<ScopeValue*> *exparray = new GrowableArray<ScopeValue*>(num_exps);
846 for( idx = 0; idx < num_exps; idx++ ) {
847 FillLocArray( idx, sfn, sfn->stack(jvms, idx), exparray, objs );
848 }
849
850 // Add in mappings of the monitors
851 assert( !method ||
852 !method->is_synchronized() ||
853 method->is_native() ||
854 num_mon > 0 ||
855 !GenerateSynchronizationCode,
856 "monitors must always exist for synchronized methods");
857
858 // Build the growable array of ScopeValues for exp stack
859 GrowableArray<MonitorValue*> *monarray = new GrowableArray<MonitorValue*>(num_mon);
860
861 // Loop over monitors and insert into array
862 for(idx = 0; idx < num_mon; idx++) {
863 // Grab the node that defines this monitor
864 Node* box_node = sfn->monitor_box(jvms, idx);
865 Node* obj_node = sfn->monitor_obj(jvms, idx);
866
867 // Create ScopeValue for object
868 ScopeValue *scval = NULL;
869
870 if( obj_node->is_SafePointScalarObject() ) {
871 SafePointScalarObjectNode* spobj = obj_node->as_SafePointScalarObject();
872 scval = Compile::sv_for_node_id(objs, spobj->_idx);
873 if (scval == NULL) {
874 const Type *t = obj_node->bottom_type();
875 ciKlass* cik = t->is_oopptr()->klass();
876 assert(cik->is_instance_klass() ||
877 cik->is_array_klass(), "Not supported allocation.");
878 ObjectValue* sv = new ObjectValue(spobj->_idx,
879 new ConstantOopWriteValue(cik->constant_encoding()));
880 Compile::set_sv_for_object_node(objs, sv);
881
882 uint first_ind = spobj->first_index();
883 for (uint i = 0; i < spobj->n_fields(); i++) {
884 Node* fld_node = sfn->in(first_ind+i);
885 (void)FillLocArray(sv->field_values()->length(), sfn, fld_node, sv->field_values(), objs);
886 }
887 scval = sv;
888 }
889 } else if( !obj_node->is_Con() ) {
890 OptoReg::Name obj_reg = _regalloc->get_reg_first(obj_node);
891 if( obj_node->bottom_type()->base() == Type::NarrowOop ) {
892 scval = new_loc_value( _regalloc, obj_reg, Location::narrowoop );
893 } else {
894 scval = new_loc_value( _regalloc, obj_reg, Location::oop );
895 }
896 } else {
897 const TypePtr *tp = obj_node->bottom_type()->make_ptr();
898 scval = new ConstantOopWriteValue(tp->is_instptr()->const_oop()->constant_encoding());
899 }
900
901 OptoReg::Name box_reg = BoxLockNode::stack_slot(box_node);
902 Location basic_lock = Location::new_stk_loc(Location::normal,_regalloc->reg2offset(box_reg));
903 while( !box_node->is_BoxLock() ) box_node = box_node->in(1);
904 monarray->append(new MonitorValue(scval, basic_lock, box_node->as_BoxLock()->is_eliminated()));
905 }
906
907 // We dump the object pool first, since deoptimization reads it in first.
908 debug_info()->dump_object_pool(objs);
909
910 // Build first class objects to pass to scope
911 DebugToken *locvals = debug_info()->create_scope_values(locarray);
912 DebugToken *expvals = debug_info()->create_scope_values(exparray);
913 DebugToken *monvals = debug_info()->create_monitor_values(monarray);
914
915 // Make method available for all Safepoints
916 ciMethod* scope_method = method ? method : _method;
917 // Describe the scope here
918 assert(jvms->bci() >= InvocationEntryBci && jvms->bci() <= 0x10000, "must be a valid or entry BCI");
919 assert(!jvms->should_reexecute() || depth == max_depth, "reexecute allowed only for the youngest");
920 // Now we can describe the scope.
921 debug_info()->describe_scope(safepoint_pc_offset, scope_method, jvms->bci(), jvms->should_reexecute(), is_method_handle_invoke, return_oop, locvals, expvals, monvals);
922 } // End jvms loop
923
924 // Mark the end of the scope set.
925 debug_info()->end_safepoint(safepoint_pc_offset);
926 }
927
928
929
930 // A simplified version of Process_OopMap_Node, to handle non-safepoints.
931 class NonSafepointEmitter {
932 Compile* C;
933 JVMState* _pending_jvms;
934 int _pending_offset;
935
936 void emit_non_safepoint();
937
938 public:
939 NonSafepointEmitter(Compile* compile) {
940 this->C = compile;
941 _pending_jvms = NULL;
942 _pending_offset = 0;
943 }
944
945 void observe_instruction(Node* n, int pc_offset) {
946 if (!C->debug_info()->recording_non_safepoints()) return;
947
948 Node_Notes* nn = C->node_notes_at(n->_idx);
949 if (nn == NULL || nn->jvms() == NULL) return;
950 if (_pending_jvms != NULL &&
951 _pending_jvms->same_calls_as(nn->jvms())) {
952 // Repeated JVMS? Stretch it up here.
953 _pending_offset = pc_offset;
954 } else {
955 if (_pending_jvms != NULL &&
956 _pending_offset < pc_offset) {
957 emit_non_safepoint();
958 }
959 _pending_jvms = NULL;
960 if (pc_offset > C->debug_info()->last_pc_offset()) {
961 // This is the only way _pending_jvms can become non-NULL:
962 _pending_jvms = nn->jvms();
963 _pending_offset = pc_offset;
964 }
965 }
966 }
967
968 // Stay out of the way of real safepoints:
969 void observe_safepoint(JVMState* jvms, int pc_offset) {
970 if (_pending_jvms != NULL &&
971 !_pending_jvms->same_calls_as(jvms) &&
972 _pending_offset < pc_offset) {
973 emit_non_safepoint();
974 }
975 _pending_jvms = NULL;
976 }
977
978 void flush_at_end() {
979 if (_pending_jvms != NULL) {
980 emit_non_safepoint();
981 }
982 _pending_jvms = NULL;
983 }
984 };
985
986 void NonSafepointEmitter::emit_non_safepoint() {
987 JVMState* youngest_jvms = _pending_jvms;
988 int pc_offset = _pending_offset;
989
990 // Clear it now:
991 _pending_jvms = NULL;
992
993 DebugInformationRecorder* debug_info = C->debug_info();
994 assert(debug_info->recording_non_safepoints(), "sanity");
995
996 debug_info->add_non_safepoint(pc_offset);
997 int max_depth = youngest_jvms->depth();
998
999 // Visit scopes from oldest to youngest.
1000 for (int depth = 1; depth <= max_depth; depth++) {
1001 JVMState* jvms = youngest_jvms->of_depth(depth);
1002 ciMethod* method = jvms->has_method() ? jvms->method() : NULL;
1003 assert(!jvms->should_reexecute() || depth==max_depth, "reexecute allowed only for the youngest");
1004 debug_info->describe_scope(pc_offset, method, jvms->bci(), jvms->should_reexecute());
1005 }
1006
1007 // Mark the end of the scope set.
1008 debug_info->end_non_safepoint(pc_offset);
1009 }
1010
1011
1012
1013 // helper for Fill_buffer bailout logic
1014 static void turn_off_compiler(Compile* C) {
1015 if (CodeCache::unallocated_capacity() >= CodeCacheMinimumFreeSpace*10) {
1016 // Do not turn off compilation if a single giant method has
1017 // blown the code cache size.
1018 C->record_failure("excessive request to CodeCache");
1019 } else {
1020 // Let CompilerBroker disable further compilations.
1021 C->record_failure("CodeCache is full");
1022 }
1023 }
1024
1025
1026 //------------------------------Fill_buffer------------------------------------
1027 void Compile::Fill_buffer() {
1028
1029 // Set the initially allocated size
1030 int code_req = initial_code_capacity;
1031 int locs_req = initial_locs_capacity;
1032 int stub_req = TraceJumps ? initial_stub_capacity * 10 : initial_stub_capacity;
1033 int const_req = initial_const_capacity;
1034 bool labels_not_set = true;
1035
1036 int pad_req = NativeCall::instruction_size;
1037 // The extra spacing after the code is necessary on some platforms.
1038 // Sometimes we need to patch in a jump after the last instruction,
1039 // if the nmethod has been deoptimized. (See 4932387, 4894843.)
1040
1041 uint i;
1042 // Compute the byte offset where we can store the deopt pc.
1043 if (fixed_slots() != 0) {
1044 _orig_pc_slot_offset_in_bytes = _regalloc->reg2offset(OptoReg::stack2reg(_orig_pc_slot));
1045 }
1046
1047 // Compute prolog code size
1048 _method_size = 0;
1049 _frame_slots = OptoReg::reg2stack(_matcher->_old_SP)+_regalloc->_framesize;
1050 #ifdef IA64
1051 if (save_argument_registers()) {
1052 // 4815101: this is a stub with implicit and unknown precision fp args.
1053 // The usual spill mechanism can only generate stfd's in this case, which
1054 // doesn't work if the fp reg to spill contains a single-precision denorm.
1055 // Instead, we hack around the normal spill mechanism using stfspill's and
1056 // ldffill's in the MachProlog and MachEpilog emit methods. We allocate
1057 // space here for the fp arg regs (f8-f15) we're going to thusly spill.
1058 //
1059 // If we ever implement 16-byte 'registers' == stack slots, we can
1060 // get rid of this hack and have SpillCopy generate stfspill/ldffill
1061 // instead of stfd/stfs/ldfd/ldfs.
1062 _frame_slots += 8*(16/BytesPerInt);
1063 }
1064 #endif
1065 assert( _frame_slots >= 0 && _frame_slots < 1000000, "sanity check" );
1066
1067 // Create an array of unused labels, one for each basic block
1068 Label *blk_labels = NEW_RESOURCE_ARRAY(Label, _cfg->_num_blocks+1);
1069
1070 for( i=0; i <= _cfg->_num_blocks; i++ ) {
1071 blk_labels[i].init();
1072 }
1073
1074 if (has_mach_constant_base_node()) {
1075 // Fill the constant table.
1076 // Note: This must happen before Shorten_branches.
1077 for (i = 0; i < _cfg->_num_blocks; i++) {
1078 Block* b = _cfg->_blocks[i];
1079
1080 for (uint j = 0; j < b->_nodes.size(); j++) {
1081 Node* n = b->_nodes[j];
1082
1083 if (n->is_Mach()) {
1084 MachNode *mach = n->as_Mach();
1085
1086 // If the MachNode is a MachConstantNode evaluate the
1087 // constant value section.
1088 if (mach->is_MachConstant()) {
1089 MachConstantNode* machcon = mach->as_MachConstant();
1090 machcon->eval_constant();
1091 }
1092 }
1093 }
1094 }
1095
1096 // Calculate the size of the constant table (including the padding
1097 // to the next section).
1098 const_req = mach_constant_base_node()->calculate_constant_table_size();
1099 }
1100
1101 // Initialize the space for the BufferBlob used to find and verify
1102 // instruction size in MachNode::emit_size()
1103 init_scratch_buffer_blob(const_req);
1104 if (failing()) return; // Out of memory
1105
1106 // If this machine supports different size branch offsets, then pre-compute
1107 // the length of the blocks
1108 if( _matcher->is_short_branch_offset(-1, 0) ) {
1109 Shorten_branches(blk_labels, code_req, locs_req, stub_req);
1110 labels_not_set = false;
1111 }
1112
1113 // nmethod and CodeBuffer count stubs & constants as part of method's code.
1114 int exception_handler_req = size_exception_handler();
1115 int deopt_handler_req = size_deopt_handler();
1116 exception_handler_req += MAX_stubs_size; // add marginal slop for handler
1117 deopt_handler_req += MAX_stubs_size; // add marginal slop for handler
1118 stub_req += MAX_stubs_size; // ensure per-stub margin
1119 code_req += MAX_inst_size; // ensure per-instruction margin
1120
1121 if (StressCodeBuffers)
1122 code_req = const_req = stub_req = exception_handler_req = deopt_handler_req = 0x10; // force expansion
1123
1124 int total_req =
1125 const_req +
1126 code_req +
1127 pad_req +
1128 stub_req +
1129 exception_handler_req +
1130 deopt_handler_req; // deopt handler
1131
1132 if (has_method_handle_invokes())
1133 total_req += deopt_handler_req; // deopt MH handler
1134
1135 CodeBuffer* cb = code_buffer();
1136 cb->initialize(total_req, locs_req);
1137
1138 // Have we run out of code space?
1139 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) {
1140 turn_off_compiler(this);
1141 return;
1142 }
1143 // Configure the code buffer.
1144 cb->initialize_consts_size(const_req);
1145 cb->initialize_stubs_size(stub_req);
1146 cb->initialize_oop_recorder(env()->oop_recorder());
1147
1148 // fill in the nop array for bundling computations
1149 MachNode *_nop_list[Bundle::_nop_count];
1150 Bundle::initialize_nops(_nop_list, this);
1151
1152 // Create oopmap set.
1153 _oop_map_set = new OopMapSet();
1154
1155 // !!!!! This preserves old handling of oopmaps for now
1156 debug_info()->set_oopmaps(_oop_map_set);
1157
1158 // Count and start of implicit null check instructions
1159 uint inct_cnt = 0;
1160 uint *inct_starts = NEW_RESOURCE_ARRAY(uint, _cfg->_num_blocks+1);
1161
1162 // Count and start of calls
1163 uint *call_returns = NEW_RESOURCE_ARRAY(uint, _cfg->_num_blocks+1);
1164
1165 uint return_offset = 0;
1166 int nop_size = (new (this) MachNopNode())->size(_regalloc);
1167
1168 int previous_offset = 0;
1169 int current_offset = 0;
1170 int last_call_offset = -1;
1171
1172 // Create an array of unused labels, one for each basic block, if printing is enabled
1173 #ifndef PRODUCT
1174 int *node_offsets = NULL;
1175 uint node_offset_limit = unique();
1176
1177
1178 if ( print_assembly() )
1179 node_offsets = NEW_RESOURCE_ARRAY(int, node_offset_limit);
1180 #endif
1181
1182 NonSafepointEmitter non_safepoints(this); // emit non-safepoints lazily
1183
1184 // ------------------
1185 // Now fill in the code buffer
1186 Node *delay_slot = NULL;
1187
1188 for( i=0; i < _cfg->_num_blocks; i++ ) {
1189 Block *b = _cfg->_blocks[i];
1190
1191 Node *head = b->head();
1192
1193 // If this block needs to start aligned (i.e, can be reached other
1194 // than by falling-thru from the previous block), then force the
1195 // start of a new bundle.
1196 if( Pipeline::requires_bundling() && starts_bundle(head) )
1197 cb->flush_bundle(true);
1198
1199 // Define the label at the beginning of the basic block
1200 if (labels_not_set) {
1201 MacroAssembler(cb).bind(blk_labels[b->_pre_order]);
1202 } else {
1203 assert(blk_labels[b->_pre_order].loc_pos() == cb->insts_size(),
1204 err_msg("label position does not match code offset: %d != %d",
1205 blk_labels[b->_pre_order].loc_pos(), cb->insts_size()));
1206 }
1207
1208 uint last_inst = b->_nodes.size();
1209
1210 // Emit block normally, except for last instruction.
1211 // Emit means "dump code bits into code buffer".
1212 for( uint j = 0; j<last_inst; j++ ) {
1213
1214 // Get the node
1215 Node* n = b->_nodes[j];
1216
1217 // See if delay slots are supported
1218 if (valid_bundle_info(n) &&
1219 node_bundling(n)->used_in_unconditional_delay()) {
1220 assert(delay_slot == NULL, "no use of delay slot node");
1221 assert(n->size(_regalloc) == Pipeline::instr_unit_size(), "delay slot instruction wrong size");
1222
1223 delay_slot = n;
1224 continue;
1225 }
1226
1227 // If this starts a new instruction group, then flush the current one
1228 // (but allow split bundles)
1229 if( Pipeline::requires_bundling() && starts_bundle(n) )
1230 cb->flush_bundle(false);
1231
1232 // The following logic is duplicated in the code ifdeffed for
1233 // ENABLE_ZAP_DEAD_LOCALS which appears above in this file. It
1234 // should be factored out. Or maybe dispersed to the nodes?
1235
1236 // Special handling for SafePoint/Call Nodes
1237 bool is_mcall = false;
1238 if( n->is_Mach() ) {
1239 MachNode *mach = n->as_Mach();
1240 is_mcall = n->is_MachCall();
1241 bool is_sfn = n->is_MachSafePoint();
1242
1243 // If this requires all previous instructions be flushed, then do so
1244 if( is_sfn || is_mcall || mach->alignment_required() != 1) {
1245 cb->flush_bundle(true);
1246 current_offset = cb->insts_size();
1247 }
1248
1249 // align the instruction if necessary
1250 int padding = mach->compute_padding(current_offset);
1251 // Make sure safepoint node for polling is distinct from a call's
1252 // return by adding a nop if needed.
1253 if (is_sfn && !is_mcall && padding == 0 && current_offset == last_call_offset ) {
1254 padding = nop_size;
1255 }
1256 assert( labels_not_set || padding == 0, "instruction should already be aligned");
1257
1258 if(padding > 0) {
1259 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size");
1260 int nops_cnt = padding / nop_size;
1261 MachNode *nop = new (this) MachNopNode(nops_cnt);
1262 b->_nodes.insert(j++, nop);
1263 last_inst++;
1264 _cfg->_bbs.map( nop->_idx, b );
1265 nop->emit(*cb, _regalloc);
1266 cb->flush_bundle(true);
1267 current_offset = cb->insts_size();
1268 }
1269
1270 // Remember the start of the last call in a basic block
1271 if (is_mcall) {
1272 MachCallNode *mcall = mach->as_MachCall();
1273
1274 // This destination address is NOT PC-relative
1275 mcall->method_set((intptr_t)mcall->entry_point());
1276
1277 // Save the return address
1278 call_returns[b->_pre_order] = current_offset + mcall->ret_addr_offset();
1279
1280 if (!mcall->is_safepoint_node()) {
1281 is_mcall = false;
1282 is_sfn = false;
1283 }
1284 }
1285
1286 // sfn will be valid whenever mcall is valid now because of inheritance
1287 if( is_sfn || is_mcall ) {
1288
1289 // Handle special safepoint nodes for synchronization
1290 if( !is_mcall ) {
1291 MachSafePointNode *sfn = mach->as_MachSafePoint();
1292 // !!!!! Stubs only need an oopmap right now, so bail out
1293 if( sfn->jvms()->method() == NULL) {
1294 // Write the oopmap directly to the code blob??!!
1295 # ifdef ENABLE_ZAP_DEAD_LOCALS
1296 assert( !is_node_getting_a_safepoint(sfn), "logic does not match; false positive");
1297 # endif
1298 continue;
1299 }
1300 } // End synchronization
1301
1302 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(),
1303 current_offset);
1304 Process_OopMap_Node(mach, current_offset);
1305 } // End if safepoint
1306
1307 // If this is a null check, then add the start of the previous instruction to the list
1308 else if( mach->is_MachNullCheck() ) {
1309 inct_starts[inct_cnt++] = previous_offset;
1310 }
1311
1312 // If this is a branch, then fill in the label with the target BB's label
1313 else if ( mach->is_Branch() ) {
1314
1315 if ( mach->ideal_Opcode() == Op_Jump ) {
1316 for (uint h = 0; h < b->_num_succs; h++ ) {
1317 Block* succs_block = b->_succs[h];
1318 for (uint j = 1; j < succs_block->num_preds(); j++) {
1319 Node* jpn = succs_block->pred(j);
1320 if ( jpn->is_JumpProj() && jpn->in(0) == mach ) {
1321 uint block_num = succs_block->non_connector()->_pre_order;
1322 Label *blkLabel = &blk_labels[block_num];
1323 mach->add_case_label(jpn->as_JumpProj()->proj_no(), blkLabel);
1324 }
1325 }
1326 }
1327 } else {
1328 // For Branchs
1329 // This requires the TRUE branch target be in succs[0]
1330 uint block_num = b->non_connector_successor(0)->_pre_order;
1331 mach->label_set( blk_labels[block_num], block_num );
1332 }
1333 }
1334
1335 #ifdef ASSERT
1336 // Check that oop-store precedes the card-mark
1337 else if( mach->ideal_Opcode() == Op_StoreCM ) {
1338 uint storeCM_idx = j;
1339 Node *oop_store = mach->in(mach->_cnt); // First precedence edge
1340 assert( oop_store != NULL, "storeCM expects a precedence edge");
1341 uint i4;
1342 for( i4 = 0; i4 < last_inst; ++i4 ) {
1343 if( b->_nodes[i4] == oop_store ) break;
1344 }
1345 // Note: This test can provide a false failure if other precedence
1346 // edges have been added to the storeCMNode.
1347 assert( i4 == last_inst || i4 < storeCM_idx, "CM card-mark executes before oop-store");
1348 }
1349 #endif
1350
1351 else if( !n->is_Proj() ) {
1352 // Remember the beginning of the previous instruction, in case
1353 // it's followed by a flag-kill and a null-check. Happens on
1354 // Intel all the time, with add-to-memory kind of opcodes.
1355 previous_offset = current_offset;
1356 }
1357 }
1358
1359 // Verify that there is sufficient space remaining
1360 cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size);
1361 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) {
1362 turn_off_compiler(this);
1363 return;
1364 }
1365
1366 // Save the offset for the listing
1367 #ifndef PRODUCT
1368 if( node_offsets && n->_idx < node_offset_limit )
1369 node_offsets[n->_idx] = cb->insts_size();
1370 #endif
1371
1372 // "Normal" instruction case
1373 n->emit(*cb, _regalloc);
1374 current_offset = cb->insts_size();
1375 non_safepoints.observe_instruction(n, current_offset);
1376
1377 // mcall is last "call" that can be a safepoint
1378 // record it so we can see if a poll will directly follow it
1379 // in which case we'll need a pad to make the PcDesc sites unique
1380 // see 5010568. This can be slightly inaccurate but conservative
1381 // in the case that return address is not actually at current_offset.
1382 // This is a small price to pay.
1383
1384 if (is_mcall) {
1385 last_call_offset = current_offset;
1386 }
1387
1388 // See if this instruction has a delay slot
1389 if ( valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
1390 assert(delay_slot != NULL, "expecting delay slot node");
1391
1392 // Back up 1 instruction
1393 cb->set_insts_end(cb->insts_end() - Pipeline::instr_unit_size());
1394
1395 // Save the offset for the listing
1396 #ifndef PRODUCT
1397 if( node_offsets && delay_slot->_idx < node_offset_limit )
1398 node_offsets[delay_slot->_idx] = cb->insts_size();
1399 #endif
1400
1401 // Support a SafePoint in the delay slot
1402 if( delay_slot->is_MachSafePoint() ) {
1403 MachNode *mach = delay_slot->as_Mach();
1404 // !!!!! Stubs only need an oopmap right now, so bail out
1405 if( !mach->is_MachCall() && mach->as_MachSafePoint()->jvms()->method() == NULL ) {
1406 // Write the oopmap directly to the code blob??!!
1407 # ifdef ENABLE_ZAP_DEAD_LOCALS
1408 assert( !is_node_getting_a_safepoint(mach), "logic does not match; false positive");
1409 # endif
1410 delay_slot = NULL;
1411 continue;
1412 }
1413
1414 int adjusted_offset = current_offset - Pipeline::instr_unit_size();
1415 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(),
1416 adjusted_offset);
1417 // Generate an OopMap entry
1418 Process_OopMap_Node(mach, adjusted_offset);
1419 }
1420
1421 // Insert the delay slot instruction
1422 delay_slot->emit(*cb, _regalloc);
1423
1424 // Don't reuse it
1425 delay_slot = NULL;
1426 }
1427
1428 } // End for all instructions in block
1429
1430 // If the next block is the top of a loop, pad this block out to align
1431 // the loop top a little. Helps prevent pipe stalls at loop back branches.
1432 if( i<_cfg->_num_blocks-1 ) {
1433 Block *nb = _cfg->_blocks[i+1];
1434 uint padding = nb->alignment_padding(current_offset);
1435 if( padding > 0 ) {
1436 MachNode *nop = new (this) MachNopNode(padding / nop_size);
1437 b->_nodes.insert( b->_nodes.size(), nop );
1438 _cfg->_bbs.map( nop->_idx, b );
1439 nop->emit(*cb, _regalloc);
1440 current_offset = cb->insts_size();
1441 }
1442 }
1443
1444 } // End of for all blocks
1445
1446 non_safepoints.flush_at_end();
1447
1448 // Offset too large?
1449 if (failing()) return;
1450
1451 // Define a pseudo-label at the end of the code
1452 MacroAssembler(cb).bind( blk_labels[_cfg->_num_blocks] );
1453
1454 // Compute the size of the first block
1455 _first_block_size = blk_labels[1].loc_pos() - blk_labels[0].loc_pos();
1456
1457 assert(cb->insts_size() < 500000, "method is unreasonably large");
1458
1459 // ------------------
1460
1461 #ifndef PRODUCT
1462 // Information on the size of the method, without the extraneous code
1463 Scheduling::increment_method_size(cb->insts_size());
1464 #endif
1465
1466 // ------------------
1467 // Fill in exception table entries.
1468 FillExceptionTables(inct_cnt, call_returns, inct_starts, blk_labels);
1469
1470 // Only java methods have exception handlers and deopt handlers
1471 if (_method) {
1472 // Emit the exception handler code.
1473 _code_offsets.set_value(CodeOffsets::Exceptions, emit_exception_handler(*cb));
1474 // Emit the deopt handler code.
1475 _code_offsets.set_value(CodeOffsets::Deopt, emit_deopt_handler(*cb));
1476
1477 // Emit the MethodHandle deopt handler code (if required).
1478 if (has_method_handle_invokes()) {
1479 // We can use the same code as for the normal deopt handler, we
1480 // just need a different entry point address.
1481 _code_offsets.set_value(CodeOffsets::DeoptMH, emit_deopt_handler(*cb));
1482 }
1483 }
1484
1485 // One last check for failed CodeBuffer::expand:
1486 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) {
1487 turn_off_compiler(this);
1488 return;
1489 }
1490
1491 #ifndef PRODUCT
1492 // Dump the assembly code, including basic-block numbers
1493 if (print_assembly()) {
1494 ttyLocker ttyl; // keep the following output all in one block
1495 if (!VMThread::should_terminate()) { // test this under the tty lock
1496 // This output goes directly to the tty, not the compiler log.
1497 // To enable tools to match it up with the compilation activity,
1498 // be sure to tag this tty output with the compile ID.
1499 if (xtty != NULL) {
1500 xtty->head("opto_assembly compile_id='%d'%s", compile_id(),
1501 is_osr_compilation() ? " compile_kind='osr'" :
1502 "");
1503 }
1504 if (method() != NULL) {
1505 method()->print_oop();
1506 print_codes();
1507 }
1508 dump_asm(node_offsets, node_offset_limit);
1509 if (xtty != NULL) {
1510 xtty->tail("opto_assembly");
1511 }
1512 }
1513 }
1514 #endif
1515
1516 }
1517
1518 void Compile::FillExceptionTables(uint cnt, uint *call_returns, uint *inct_starts, Label *blk_labels) {
1519 _inc_table.set_size(cnt);
1520
1521 uint inct_cnt = 0;
1522 for( uint i=0; i<_cfg->_num_blocks; i++ ) {
1523 Block *b = _cfg->_blocks[i];
1524 Node *n = NULL;
1525 int j;
1526
1527 // Find the branch; ignore trailing NOPs.
1528 for( j = b->_nodes.size()-1; j>=0; j-- ) {
1529 n = b->_nodes[j];
1530 if( !n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con )
1531 break;
1532 }
1533
1534 // If we didn't find anything, continue
1535 if( j < 0 ) continue;
1536
1537 // Compute ExceptionHandlerTable subtable entry and add it
1538 // (skip empty blocks)
1539 if( n->is_Catch() ) {
1540
1541 // Get the offset of the return from the call
1542 uint call_return = call_returns[b->_pre_order];
1543 #ifdef ASSERT
1544 assert( call_return > 0, "no call seen for this basic block" );
1545 while( b->_nodes[--j]->Opcode() == Op_MachProj ) ;
1546 assert( b->_nodes[j]->is_Call(), "CatchProj must follow call" );
1547 #endif
1548 // last instruction is a CatchNode, find it's CatchProjNodes
1549 int nof_succs = b->_num_succs;
1550 // allocate space
1551 GrowableArray<intptr_t> handler_bcis(nof_succs);
1552 GrowableArray<intptr_t> handler_pcos(nof_succs);
1553 // iterate through all successors
1554 for (int j = 0; j < nof_succs; j++) {
1555 Block* s = b->_succs[j];
1556 bool found_p = false;
1557 for( uint k = 1; k < s->num_preds(); k++ ) {
1558 Node *pk = s->pred(k);
1559 if( pk->is_CatchProj() && pk->in(0) == n ) {
1560 const CatchProjNode* p = pk->as_CatchProj();
1561 found_p = true;
1562 // add the corresponding handler bci & pco information
1563 if( p->_con != CatchProjNode::fall_through_index ) {
1564 // p leads to an exception handler (and is not fall through)
1565 assert(s == _cfg->_blocks[s->_pre_order],"bad numbering");
1566 // no duplicates, please
1567 if( !handler_bcis.contains(p->handler_bci()) ) {
1568 uint block_num = s->non_connector()->_pre_order;
1569 handler_bcis.append(p->handler_bci());
1570 handler_pcos.append(blk_labels[block_num].loc_pos());
1571 }
1572 }
1573 }
1574 }
1575 assert(found_p, "no matching predecessor found");
1576 // Note: Due to empty block removal, one block may have
1577 // several CatchProj inputs, from the same Catch.
1578 }
1579
1580 // Set the offset of the return from the call
1581 _handler_table.add_subtable(call_return, &handler_bcis, NULL, &handler_pcos);
1582 continue;
1583 }
1584
1585 // Handle implicit null exception table updates
1586 if( n->is_MachNullCheck() ) {
1587 uint block_num = b->non_connector_successor(0)->_pre_order;
1588 _inc_table.append( inct_starts[inct_cnt++], blk_labels[block_num].loc_pos() );
1589 continue;
1590 }
1591 } // End of for all blocks fill in exception table entries
1592 }
1593
1594 // Static Variables
1595 #ifndef PRODUCT
1596 uint Scheduling::_total_nop_size = 0;
1597 uint Scheduling::_total_method_size = 0;
1598 uint Scheduling::_total_branches = 0;
1599 uint Scheduling::_total_unconditional_delays = 0;
1600 uint Scheduling::_total_instructions_per_bundle[Pipeline::_max_instrs_per_cycle+1];
1601 #endif
1602
1603 // Initializer for class Scheduling
1604
1605 Scheduling::Scheduling(Arena *arena, Compile &compile)
1606 : _arena(arena),
1607 _cfg(compile.cfg()),
1608 _bbs(compile.cfg()->_bbs),
1609 _regalloc(compile.regalloc()),
1610 _reg_node(arena),
1611 _bundle_instr_count(0),
1612 _bundle_cycle_number(0),
1613 _scheduled(arena),
1614 _available(arena),
1615 _next_node(NULL),
1616 _bundle_use(0, 0, resource_count, &_bundle_use_elements[0]),
1617 _pinch_free_list(arena)
1618 #ifndef PRODUCT
1619 , _branches(0)
1620 , _unconditional_delays(0)
1621 #endif
1622 {
1623 // Create a MachNopNode
1624 _nop = new (&compile) MachNopNode();
1625
1626 // Now that the nops are in the array, save the count
1627 // (but allow entries for the nops)
1628 _node_bundling_limit = compile.unique();
1629 uint node_max = _regalloc->node_regs_max_index();
1630
1631 compile.set_node_bundling_limit(_node_bundling_limit);
1632
1633 // This one is persistent within the Compile class
1634 _node_bundling_base = NEW_ARENA_ARRAY(compile.comp_arena(), Bundle, node_max);
1635
1636 // Allocate space for fixed-size arrays
1637 _node_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max);
1638 _uses = NEW_ARENA_ARRAY(arena, short, node_max);
1639 _current_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max);
1640
1641 // Clear the arrays
1642 memset(_node_bundling_base, 0, node_max * sizeof(Bundle));
1643 memset(_node_latency, 0, node_max * sizeof(unsigned short));
1644 memset(_uses, 0, node_max * sizeof(short));
1645 memset(_current_latency, 0, node_max * sizeof(unsigned short));
1646
1647 // Clear the bundling information
1648 memcpy(_bundle_use_elements,
1649 Pipeline_Use::elaborated_elements,
1650 sizeof(Pipeline_Use::elaborated_elements));
1651
1652 // Get the last node
1653 Block *bb = _cfg->_blocks[_cfg->_blocks.size()-1];
1654
1655 _next_node = bb->_nodes[bb->_nodes.size()-1];
1656 }
1657
1658 #ifndef PRODUCT
1659 // Scheduling destructor
1660 Scheduling::~Scheduling() {
1661 _total_branches += _branches;
1662 _total_unconditional_delays += _unconditional_delays;
1663 }
1664 #endif
1665
1666 // Step ahead "i" cycles
1667 void Scheduling::step(uint i) {
1668
1669 Bundle *bundle = node_bundling(_next_node);
1670 bundle->set_starts_bundle();
1671
1672 // Update the bundle record, but leave the flags information alone
1673 if (_bundle_instr_count > 0) {
1674 bundle->set_instr_count(_bundle_instr_count);
1675 bundle->set_resources_used(_bundle_use.resourcesUsed());
1676 }
1677
1678 // Update the state information
1679 _bundle_instr_count = 0;
1680 _bundle_cycle_number += i;
1681 _bundle_use.step(i);
1682 }
1683
1684 void Scheduling::step_and_clear() {
1685 Bundle *bundle = node_bundling(_next_node);
1686 bundle->set_starts_bundle();
1687
1688 // Update the bundle record
1689 if (_bundle_instr_count > 0) {
1690 bundle->set_instr_count(_bundle_instr_count);
1691 bundle->set_resources_used(_bundle_use.resourcesUsed());
1692
1693 _bundle_cycle_number += 1;
1694 }
1695
1696 // Clear the bundling information
1697 _bundle_instr_count = 0;
1698 _bundle_use.reset();
1699
1700 memcpy(_bundle_use_elements,
1701 Pipeline_Use::elaborated_elements,
1702 sizeof(Pipeline_Use::elaborated_elements));
1703 }
1704
1705 //------------------------------ScheduleAndBundle------------------------------
1706 // Perform instruction scheduling and bundling over the sequence of
1707 // instructions in backwards order.
1708 void Compile::ScheduleAndBundle() {
1709
1710 // Don't optimize this if it isn't a method
1711 if (!_method)
1712 return;
1713
1714 // Don't optimize this if scheduling is disabled
1715 if (!do_scheduling())
1716 return;
1717
1718 NOT_PRODUCT( TracePhase t2("isched", &_t_instrSched, TimeCompiler); )
1719
1720 // Create a data structure for all the scheduling information
1721 Scheduling scheduling(Thread::current()->resource_area(), *this);
1722
1723 // Initialize the space for the BufferBlob used to find and verify
1724 // instruction size in MachNode::emit_size()
1725 init_scratch_buffer_blob(MAX_const_size);
1726 if (failing()) return; // Out of memory
1727
1728 // Walk backwards over each basic block, computing the needed alignment
1729 // Walk over all the basic blocks
1730 scheduling.DoScheduling();
1731
1732 // Clear the BufferBlob used for scheduling.
1733 clear_scratch_buffer_blob();
1734 }
1735
1736 //------------------------------ComputeLocalLatenciesForward-------------------
1737 // Compute the latency of all the instructions. This is fairly simple,
1738 // because we already have a legal ordering. Walk over the instructions
1739 // from first to last, and compute the latency of the instruction based
1740 // on the latency of the preceding instruction(s).
1741 void Scheduling::ComputeLocalLatenciesForward(const Block *bb) {
1742 #ifndef PRODUCT
1743 if (_cfg->C->trace_opto_output())
1744 tty->print("# -> ComputeLocalLatenciesForward\n");
1745 #endif
1746
1747 // Walk over all the schedulable instructions
1748 for( uint j=_bb_start; j < _bb_end; j++ ) {
1749
1750 // This is a kludge, forcing all latency calculations to start at 1.
1751 // Used to allow latency 0 to force an instruction to the beginning
1752 // of the bb
1753 uint latency = 1;
1754 Node *use = bb->_nodes[j];
1755 uint nlen = use->len();
1756
1757 // Walk over all the inputs
1758 for ( uint k=0; k < nlen; k++ ) {
1759 Node *def = use->in(k);
1760 if (!def)
1761 continue;
1762
1763 uint l = _node_latency[def->_idx] + use->latency(k);
1764 if (latency < l)
1765 latency = l;
1766 }
1767
1768 _node_latency[use->_idx] = latency;
1769
1770 #ifndef PRODUCT
1771 if (_cfg->C->trace_opto_output()) {
1772 tty->print("# latency %4d: ", latency);
1773 use->dump();
1774 }
1775 #endif
1776 }
1777
1778 #ifndef PRODUCT
1779 if (_cfg->C->trace_opto_output())
1780 tty->print("# <- ComputeLocalLatenciesForward\n");
1781 #endif
1782
1783 } // end ComputeLocalLatenciesForward
1784
1785 // See if this node fits into the present instruction bundle
1786 bool Scheduling::NodeFitsInBundle(Node *n) {
1787 uint n_idx = n->_idx;
1788
1789 // If this is the unconditional delay instruction, then it fits
1790 if (n == _unconditional_delay_slot) {
1791 #ifndef PRODUCT
1792 if (_cfg->C->trace_opto_output())
1793 tty->print("# NodeFitsInBundle [%4d]: TRUE; is in unconditional delay slot\n", n->_idx);
1794 #endif
1795 return (true);
1796 }
1797
1798 // If the node cannot be scheduled this cycle, skip it
1799 if (_current_latency[n_idx] > _bundle_cycle_number) {
1800 #ifndef PRODUCT
1801 if (_cfg->C->trace_opto_output())
1802 tty->print("# NodeFitsInBundle [%4d]: FALSE; latency %4d > %d\n",
1803 n->_idx, _current_latency[n_idx], _bundle_cycle_number);
1804 #endif
1805 return (false);
1806 }
1807
1808 const Pipeline *node_pipeline = n->pipeline();
1809
1810 uint instruction_count = node_pipeline->instructionCount();
1811 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0)
1812 instruction_count = 0;
1813 else if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot)
1814 instruction_count++;
1815
1816 if (_bundle_instr_count + instruction_count > Pipeline::_max_instrs_per_cycle) {
1817 #ifndef PRODUCT
1818 if (_cfg->C->trace_opto_output())
1819 tty->print("# NodeFitsInBundle [%4d]: FALSE; too many instructions: %d > %d\n",
1820 n->_idx, _bundle_instr_count + instruction_count, Pipeline::_max_instrs_per_cycle);
1821 #endif
1822 return (false);
1823 }
1824
1825 // Don't allow non-machine nodes to be handled this way
1826 if (!n->is_Mach() && instruction_count == 0)
1827 return (false);
1828
1829 // See if there is any overlap
1830 uint delay = _bundle_use.full_latency(0, node_pipeline->resourceUse());
1831
1832 if (delay > 0) {
1833 #ifndef PRODUCT
1834 if (_cfg->C->trace_opto_output())
1835 tty->print("# NodeFitsInBundle [%4d]: FALSE; functional units overlap\n", n_idx);
1836 #endif
1837 return false;
1838 }
1839
1840 #ifndef PRODUCT
1841 if (_cfg->C->trace_opto_output())
1842 tty->print("# NodeFitsInBundle [%4d]: TRUE\n", n_idx);
1843 #endif
1844
1845 return true;
1846 }
1847
1848 Node * Scheduling::ChooseNodeToBundle() {
1849 uint siz = _available.size();
1850
1851 if (siz == 0) {
1852
1853 #ifndef PRODUCT
1854 if (_cfg->C->trace_opto_output())
1855 tty->print("# ChooseNodeToBundle: NULL\n");
1856 #endif
1857 return (NULL);
1858 }
1859
1860 // Fast path, if only 1 instruction in the bundle
1861 if (siz == 1) {
1862 #ifndef PRODUCT
1863 if (_cfg->C->trace_opto_output()) {
1864 tty->print("# ChooseNodeToBundle (only 1): ");
1865 _available[0]->dump();
1866 }
1867 #endif
1868 return (_available[0]);
1869 }
1870
1871 // Don't bother, if the bundle is already full
1872 if (_bundle_instr_count < Pipeline::_max_instrs_per_cycle) {
1873 for ( uint i = 0; i < siz; i++ ) {
1874 Node *n = _available[i];
1875
1876 // Skip projections, we'll handle them another way
1877 if (n->is_Proj())
1878 continue;
1879
1880 // This presupposed that instructions are inserted into the
1881 // available list in a legality order; i.e. instructions that
1882 // must be inserted first are at the head of the list
1883 if (NodeFitsInBundle(n)) {
1884 #ifndef PRODUCT
1885 if (_cfg->C->trace_opto_output()) {
1886 tty->print("# ChooseNodeToBundle: ");
1887 n->dump();
1888 }
1889 #endif
1890 return (n);
1891 }
1892 }
1893 }
1894
1895 // Nothing fits in this bundle, choose the highest priority
1896 #ifndef PRODUCT
1897 if (_cfg->C->trace_opto_output()) {
1898 tty->print("# ChooseNodeToBundle: ");
1899 _available[0]->dump();
1900 }
1901 #endif
1902
1903 return _available[0];
1904 }
1905
1906 //------------------------------AddNodeToAvailableList-------------------------
1907 void Scheduling::AddNodeToAvailableList(Node *n) {
1908 assert( !n->is_Proj(), "projections never directly made available" );
1909 #ifndef PRODUCT
1910 if (_cfg->C->trace_opto_output()) {
1911 tty->print("# AddNodeToAvailableList: ");
1912 n->dump();
1913 }
1914 #endif
1915
1916 int latency = _current_latency[n->_idx];
1917
1918 // Insert in latency order (insertion sort)
1919 uint i;
1920 for ( i=0; i < _available.size(); i++ )
1921 if (_current_latency[_available[i]->_idx] > latency)
1922 break;
1923
1924 // Special Check for compares following branches
1925 if( n->is_Mach() && _scheduled.size() > 0 ) {
1926 int op = n->as_Mach()->ideal_Opcode();
1927 Node *last = _scheduled[0];
1928 if( last->is_MachIf() && last->in(1) == n &&
1929 ( op == Op_CmpI ||
1930 op == Op_CmpU ||
1931 op == Op_CmpP ||
1932 op == Op_CmpF ||
1933 op == Op_CmpD ||
1934 op == Op_CmpL ) ) {
1935
1936 // Recalculate position, moving to front of same latency
1937 for ( i=0 ; i < _available.size(); i++ )
1938 if (_current_latency[_available[i]->_idx] >= latency)
1939 break;
1940 }
1941 }
1942
1943 // Insert the node in the available list
1944 _available.insert(i, n);
1945
1946 #ifndef PRODUCT
1947 if (_cfg->C->trace_opto_output())
1948 dump_available();
1949 #endif
1950 }
1951
1952 //------------------------------DecrementUseCounts-----------------------------
1953 void Scheduling::DecrementUseCounts(Node *n, const Block *bb) {
1954 for ( uint i=0; i < n->len(); i++ ) {
1955 Node *def = n->in(i);
1956 if (!def) continue;
1957 if( def->is_Proj() ) // If this is a machine projection, then
1958 def = def->in(0); // propagate usage thru to the base instruction
1959
1960 if( _bbs[def->_idx] != bb ) // Ignore if not block-local
1961 continue;
1962
1963 // Compute the latency
1964 uint l = _bundle_cycle_number + n->latency(i);
1965 if (_current_latency[def->_idx] < l)
1966 _current_latency[def->_idx] = l;
1967
1968 // If this does not have uses then schedule it
1969 if ((--_uses[def->_idx]) == 0)
1970 AddNodeToAvailableList(def);
1971 }
1972 }
1973
1974 //------------------------------AddNodeToBundle--------------------------------
1975 void Scheduling::AddNodeToBundle(Node *n, const Block *bb) {
1976 #ifndef PRODUCT
1977 if (_cfg->C->trace_opto_output()) {
1978 tty->print("# AddNodeToBundle: ");
1979 n->dump();
1980 }
1981 #endif
1982
1983 // Remove this from the available list
1984 uint i;
1985 for (i = 0; i < _available.size(); i++)
1986 if (_available[i] == n)
1987 break;
1988 assert(i < _available.size(), "entry in _available list not found");
1989 _available.remove(i);
1990
1991 // See if this fits in the current bundle
1992 const Pipeline *node_pipeline = n->pipeline();
1993 const Pipeline_Use& node_usage = node_pipeline->resourceUse();
1994
1995 // Check for instructions to be placed in the delay slot. We
1996 // do this before we actually schedule the current instruction,
1997 // because the delay slot follows the current instruction.
1998 if (Pipeline::_branch_has_delay_slot &&
1999 node_pipeline->hasBranchDelay() &&
2000 !_unconditional_delay_slot) {
2001
2002 uint siz = _available.size();
2003
2004 // Conditional branches can support an instruction that
2005 // is unconditionally executed and not dependent by the
2006 // branch, OR a conditionally executed instruction if
2007 // the branch is taken. In practice, this means that
2008 // the first instruction at the branch target is
2009 // copied to the delay slot, and the branch goes to
2010 // the instruction after that at the branch target
2011 if ( n->is_Mach() && n->is_Branch() ) {
2012
2013 assert( !n->is_MachNullCheck(), "should not look for delay slot for Null Check" );
2014 assert( !n->is_Catch(), "should not look for delay slot for Catch" );
2015
2016 #ifndef PRODUCT
2017 _branches++;
2018 #endif
2019
2020 // At least 1 instruction is on the available list
2021 // that is not dependent on the branch
2022 for (uint i = 0; i < siz; i++) {
2023 Node *d = _available[i];
2024 const Pipeline *avail_pipeline = d->pipeline();
2025
2026 // Don't allow safepoints in the branch shadow, that will
2027 // cause a number of difficulties
2028 if ( avail_pipeline->instructionCount() == 1 &&
2029 !avail_pipeline->hasMultipleBundles() &&
2030 !avail_pipeline->hasBranchDelay() &&
2031 Pipeline::instr_has_unit_size() &&
2032 d->size(_regalloc) == Pipeline::instr_unit_size() &&
2033 NodeFitsInBundle(d) &&
2034 !node_bundling(d)->used_in_delay()) {
2035
2036 if (d->is_Mach() && !d->is_MachSafePoint()) {
2037 // A node that fits in the delay slot was found, so we need to
2038 // set the appropriate bits in the bundle pipeline information so
2039 // that it correctly indicates resource usage. Later, when we
2040 // attempt to add this instruction to the bundle, we will skip
2041 // setting the resource usage.
2042 _unconditional_delay_slot = d;
2043 node_bundling(n)->set_use_unconditional_delay();
2044 node_bundling(d)->set_used_in_unconditional_delay();
2045 _bundle_use.add_usage(avail_pipeline->resourceUse());
2046 _current_latency[d->_idx] = _bundle_cycle_number;
2047 _next_node = d;
2048 ++_bundle_instr_count;
2049 #ifndef PRODUCT
2050 _unconditional_delays++;
2051 #endif
2052 break;
2053 }
2054 }
2055 }
2056 }
2057
2058 // No delay slot, add a nop to the usage
2059 if (!_unconditional_delay_slot) {
2060 // See if adding an instruction in the delay slot will overflow
2061 // the bundle.
2062 if (!NodeFitsInBundle(_nop)) {
2063 #ifndef PRODUCT
2064 if (_cfg->C->trace_opto_output())
2065 tty->print("# *** STEP(1 instruction for delay slot) ***\n");
2066 #endif
2067 step(1);
2068 }
2069
2070 _bundle_use.add_usage(_nop->pipeline()->resourceUse());
2071 _next_node = _nop;
2072 ++_bundle_instr_count;
2073 }
2074
2075 // See if the instruction in the delay slot requires a
2076 // step of the bundles
2077 if (!NodeFitsInBundle(n)) {
2078 #ifndef PRODUCT
2079 if (_cfg->C->trace_opto_output())
2080 tty->print("# *** STEP(branch won't fit) ***\n");
2081 #endif
2082 // Update the state information
2083 _bundle_instr_count = 0;
2084 _bundle_cycle_number += 1;
2085 _bundle_use.step(1);
2086 }
2087 }
2088
2089 // Get the number of instructions
2090 uint instruction_count = node_pipeline->instructionCount();
2091 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0)
2092 instruction_count = 0;
2093
2094 // Compute the latency information
2095 uint delay = 0;
2096
2097 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) {
2098 int relative_latency = _current_latency[n->_idx] - _bundle_cycle_number;
2099 if (relative_latency < 0)
2100 relative_latency = 0;
2101
2102 delay = _bundle_use.full_latency(relative_latency, node_usage);
2103
2104 // Does not fit in this bundle, start a new one
2105 if (delay > 0) {
2106 step(delay);
2107
2108 #ifndef PRODUCT
2109 if (_cfg->C->trace_opto_output())
2110 tty->print("# *** STEP(%d) ***\n", delay);
2111 #endif
2112 }
2113 }
2114
2115 // If this was placed in the delay slot, ignore it
2116 if (n != _unconditional_delay_slot) {
2117
2118 if (delay == 0) {
2119 if (node_pipeline->hasMultipleBundles()) {
2120 #ifndef PRODUCT
2121 if (_cfg->C->trace_opto_output())
2122 tty->print("# *** STEP(multiple instructions) ***\n");
2123 #endif
2124 step(1);
2125 }
2126
2127 else if (instruction_count + _bundle_instr_count > Pipeline::_max_instrs_per_cycle) {
2128 #ifndef PRODUCT
2129 if (_cfg->C->trace_opto_output())
2130 tty->print("# *** STEP(%d >= %d instructions) ***\n",
2131 instruction_count + _bundle_instr_count,
2132 Pipeline::_max_instrs_per_cycle);
2133 #endif
2134 step(1);
2135 }
2136 }
2137
2138 if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot)
2139 _bundle_instr_count++;
2140
2141 // Set the node's latency
2142 _current_latency[n->_idx] = _bundle_cycle_number;
2143
2144 // Now merge the functional unit information
2145 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode())
2146 _bundle_use.add_usage(node_usage);
2147
2148 // Increment the number of instructions in this bundle
2149 _bundle_instr_count += instruction_count;
2150
2151 // Remember this node for later
2152 if (n->is_Mach())
2153 _next_node = n;
2154 }
2155
2156 // It's possible to have a BoxLock in the graph and in the _bbs mapping but
2157 // not in the bb->_nodes array. This happens for debug-info-only BoxLocks.
2158 // 'Schedule' them (basically ignore in the schedule) but do not insert them
2159 // into the block. All other scheduled nodes get put in the schedule here.
2160 int op = n->Opcode();
2161 if( (op == Op_Node && n->req() == 0) || // anti-dependence node OR
2162 (op != Op_Node && // Not an unused antidepedence node and
2163 // not an unallocated boxlock
2164 (OptoReg::is_valid(_regalloc->get_reg_first(n)) || op != Op_BoxLock)) ) {
2165
2166 // Push any trailing projections
2167 if( bb->_nodes[bb->_nodes.size()-1] != n ) {
2168 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2169 Node *foi = n->fast_out(i);
2170 if( foi->is_Proj() )
2171 _scheduled.push(foi);
2172 }
2173 }
2174
2175 // Put the instruction in the schedule list
2176 _scheduled.push(n);
2177 }
2178
2179 #ifndef PRODUCT
2180 if (_cfg->C->trace_opto_output())
2181 dump_available();
2182 #endif
2183
2184 // Walk all the definitions, decrementing use counts, and
2185 // if a definition has a 0 use count, place it in the available list.
2186 DecrementUseCounts(n,bb);
2187 }
2188
2189 //------------------------------ComputeUseCount--------------------------------
2190 // This method sets the use count within a basic block. We will ignore all
2191 // uses outside the current basic block. As we are doing a backwards walk,
2192 // any node we reach that has a use count of 0 may be scheduled. This also
2193 // avoids the problem of cyclic references from phi nodes, as long as phi
2194 // nodes are at the front of the basic block. This method also initializes
2195 // the available list to the set of instructions that have no uses within this
2196 // basic block.
2197 void Scheduling::ComputeUseCount(const Block *bb) {
2198 #ifndef PRODUCT
2199 if (_cfg->C->trace_opto_output())
2200 tty->print("# -> ComputeUseCount\n");
2201 #endif
2202
2203 // Clear the list of available and scheduled instructions, just in case
2204 _available.clear();
2205 _scheduled.clear();
2206
2207 // No delay slot specified
2208 _unconditional_delay_slot = NULL;
2209
2210 #ifdef ASSERT
2211 for( uint i=0; i < bb->_nodes.size(); i++ )
2212 assert( _uses[bb->_nodes[i]->_idx] == 0, "_use array not clean" );
2213 #endif
2214
2215 // Force the _uses count to never go to zero for unscheduable pieces
2216 // of the block
2217 for( uint k = 0; k < _bb_start; k++ )
2218 _uses[bb->_nodes[k]->_idx] = 1;
2219 for( uint l = _bb_end; l < bb->_nodes.size(); l++ )
2220 _uses[bb->_nodes[l]->_idx] = 1;
2221
2222 // Iterate backwards over the instructions in the block. Don't count the
2223 // branch projections at end or the block header instructions.
2224 for( uint j = _bb_end-1; j >= _bb_start; j-- ) {
2225 Node *n = bb->_nodes[j];
2226 if( n->is_Proj() ) continue; // Projections handled another way
2227
2228 // Account for all uses
2229 for ( uint k = 0; k < n->len(); k++ ) {
2230 Node *inp = n->in(k);
2231 if (!inp) continue;
2232 assert(inp != n, "no cycles allowed" );
2233 if( _bbs[inp->_idx] == bb ) { // Block-local use?
2234 if( inp->is_Proj() ) // Skip through Proj's
2235 inp = inp->in(0);
2236 ++_uses[inp->_idx]; // Count 1 block-local use
2237 }
2238 }
2239
2240 // If this instruction has a 0 use count, then it is available
2241 if (!_uses[n->_idx]) {
2242 _current_latency[n->_idx] = _bundle_cycle_number;
2243 AddNodeToAvailableList(n);
2244 }
2245
2246 #ifndef PRODUCT
2247 if (_cfg->C->trace_opto_output()) {
2248 tty->print("# uses: %3d: ", _uses[n->_idx]);
2249 n->dump();
2250 }
2251 #endif
2252 }
2253
2254 #ifndef PRODUCT
2255 if (_cfg->C->trace_opto_output())
2256 tty->print("# <- ComputeUseCount\n");
2257 #endif
2258 }
2259
2260 // This routine performs scheduling on each basic block in reverse order,
2261 // using instruction latencies and taking into account function unit
2262 // availability.
2263 void Scheduling::DoScheduling() {
2264 #ifndef PRODUCT
2265 if (_cfg->C->trace_opto_output())
2266 tty->print("# -> DoScheduling\n");
2267 #endif
2268
2269 Block *succ_bb = NULL;
2270 Block *bb;
2271
2272 // Walk over all the basic blocks in reverse order
2273 for( int i=_cfg->_num_blocks-1; i >= 0; succ_bb = bb, i-- ) {
2274 bb = _cfg->_blocks[i];
2275
2276 #ifndef PRODUCT
2277 if (_cfg->C->trace_opto_output()) {
2278 tty->print("# Schedule BB#%03d (initial)\n", i);
2279 for (uint j = 0; j < bb->_nodes.size(); j++)
2280 bb->_nodes[j]->dump();
2281 }
2282 #endif
2283
2284 // On the head node, skip processing
2285 if( bb == _cfg->_broot )
2286 continue;
2287
2288 // Skip empty, connector blocks
2289 if (bb->is_connector())
2290 continue;
2291
2292 // If the following block is not the sole successor of
2293 // this one, then reset the pipeline information
2294 if (bb->_num_succs != 1 || bb->non_connector_successor(0) != succ_bb) {
2295 #ifndef PRODUCT
2296 if (_cfg->C->trace_opto_output()) {
2297 tty->print("*** bundle start of next BB, node %d, for %d instructions\n",
2298 _next_node->_idx, _bundle_instr_count);
2299 }
2300 #endif
2301 step_and_clear();
2302 }
2303
2304 // Leave untouched the starting instruction, any Phis, a CreateEx node
2305 // or Top. bb->_nodes[_bb_start] is the first schedulable instruction.
2306 _bb_end = bb->_nodes.size()-1;
2307 for( _bb_start=1; _bb_start <= _bb_end; _bb_start++ ) {
2308 Node *n = bb->_nodes[_bb_start];
2309 // Things not matched, like Phinodes and ProjNodes don't get scheduled.
2310 // Also, MachIdealNodes do not get scheduled
2311 if( !n->is_Mach() ) continue; // Skip non-machine nodes
2312 MachNode *mach = n->as_Mach();
2313 int iop = mach->ideal_Opcode();
2314 if( iop == Op_CreateEx ) continue; // CreateEx is pinned
2315 if( iop == Op_Con ) continue; // Do not schedule Top
2316 if( iop == Op_Node && // Do not schedule PhiNodes, ProjNodes
2317 mach->pipeline() == MachNode::pipeline_class() &&
2318 !n->is_SpillCopy() ) // Breakpoints, Prolog, etc
2319 continue;
2320 break; // Funny loop structure to be sure...
2321 }
2322 // Compute last "interesting" instruction in block - last instruction we
2323 // might schedule. _bb_end points just after last schedulable inst. We
2324 // normally schedule conditional branches (despite them being forced last
2325 // in the block), because they have delay slots we can fill. Calls all
2326 // have their delay slots filled in the template expansions, so we don't
2327 // bother scheduling them.
2328 Node *last = bb->_nodes[_bb_end];
2329 if( last->is_Catch() ||
2330 // Exclude unreachable path case when Halt node is in a separate block.
2331 (_bb_end > 1 && last->is_Mach() && last->as_Mach()->ideal_Opcode() == Op_Halt) ) {
2332 // There must be a prior call. Skip it.
2333 while( !bb->_nodes[--_bb_end]->is_Call() ) {
2334 assert( bb->_nodes[_bb_end]->is_Proj(), "skipping projections after expected call" );
2335 }
2336 } else if( last->is_MachNullCheck() ) {
2337 // Backup so the last null-checked memory instruction is
2338 // outside the schedulable range. Skip over the nullcheck,
2339 // projection, and the memory nodes.
2340 Node *mem = last->in(1);
2341 do {
2342 _bb_end--;
2343 } while (mem != bb->_nodes[_bb_end]);
2344 } else {
2345 // Set _bb_end to point after last schedulable inst.
2346 _bb_end++;
2347 }
2348
2349 assert( _bb_start <= _bb_end, "inverted block ends" );
2350
2351 // Compute the register antidependencies for the basic block
2352 ComputeRegisterAntidependencies(bb);
2353 if (_cfg->C->failing()) return; // too many D-U pinch points
2354
2355 // Compute intra-bb latencies for the nodes
2356 ComputeLocalLatenciesForward(bb);
2357
2358 // Compute the usage within the block, and set the list of all nodes
2359 // in the block that have no uses within the block.
2360 ComputeUseCount(bb);
2361
2362 // Schedule the remaining instructions in the block
2363 while ( _available.size() > 0 ) {
2364 Node *n = ChooseNodeToBundle();
2365 AddNodeToBundle(n,bb);
2366 }
2367
2368 assert( _scheduled.size() == _bb_end - _bb_start, "wrong number of instructions" );
2369 #ifdef ASSERT
2370 for( uint l = _bb_start; l < _bb_end; l++ ) {
2371 Node *n = bb->_nodes[l];
2372 uint m;
2373 for( m = 0; m < _bb_end-_bb_start; m++ )
2374 if( _scheduled[m] == n )
2375 break;
2376 assert( m < _bb_end-_bb_start, "instruction missing in schedule" );
2377 }
2378 #endif
2379
2380 // Now copy the instructions (in reverse order) back to the block
2381 for ( uint k = _bb_start; k < _bb_end; k++ )
2382 bb->_nodes.map(k, _scheduled[_bb_end-k-1]);
2383
2384 #ifndef PRODUCT
2385 if (_cfg->C->trace_opto_output()) {
2386 tty->print("# Schedule BB#%03d (final)\n", i);
2387 uint current = 0;
2388 for (uint j = 0; j < bb->_nodes.size(); j++) {
2389 Node *n = bb->_nodes[j];
2390 if( valid_bundle_info(n) ) {
2391 Bundle *bundle = node_bundling(n);
2392 if (bundle->instr_count() > 0 || bundle->flags() > 0) {
2393 tty->print("*** Bundle: ");
2394 bundle->dump();
2395 }
2396 n->dump();
2397 }
2398 }
2399 }
2400 #endif
2401 #ifdef ASSERT
2402 verify_good_schedule(bb,"after block local scheduling");
2403 #endif
2404 }
2405
2406 #ifndef PRODUCT
2407 if (_cfg->C->trace_opto_output())
2408 tty->print("# <- DoScheduling\n");
2409 #endif
2410
2411 // Record final node-bundling array location
2412 _regalloc->C->set_node_bundling_base(_node_bundling_base);
2413
2414 } // end DoScheduling
2415
2416 //------------------------------verify_good_schedule---------------------------
2417 // Verify that no live-range used in the block is killed in the block by a
2418 // wrong DEF. This doesn't verify live-ranges that span blocks.
2419
2420 // Check for edge existence. Used to avoid adding redundant precedence edges.
2421 static bool edge_from_to( Node *from, Node *to ) {
2422 for( uint i=0; i<from->len(); i++ )
2423 if( from->in(i) == to )
2424 return true;
2425 return false;
2426 }
2427
2428 #ifdef ASSERT
2429 //------------------------------verify_do_def----------------------------------
2430 void Scheduling::verify_do_def( Node *n, OptoReg::Name def, const char *msg ) {
2431 // Check for bad kills
2432 if( OptoReg::is_valid(def) ) { // Ignore stores & control flow
2433 Node *prior_use = _reg_node[def];
2434 if( prior_use && !edge_from_to(prior_use,n) ) {
2435 tty->print("%s = ",OptoReg::as_VMReg(def)->name());
2436 n->dump();
2437 tty->print_cr("...");
2438 prior_use->dump();
2439 assert(edge_from_to(prior_use,n),msg);
2440 }
2441 _reg_node.map(def,NULL); // Kill live USEs
2442 }
2443 }
2444
2445 //------------------------------verify_good_schedule---------------------------
2446 void Scheduling::verify_good_schedule( Block *b, const char *msg ) {
2447
2448 // Zap to something reasonable for the verify code
2449 _reg_node.clear();
2450
2451 // Walk over the block backwards. Check to make sure each DEF doesn't
2452 // kill a live value (other than the one it's supposed to). Add each
2453 // USE to the live set.
2454 for( uint i = b->_nodes.size()-1; i >= _bb_start; i-- ) {
2455 Node *n = b->_nodes[i];
2456 int n_op = n->Opcode();
2457 if( n_op == Op_MachProj && n->ideal_reg() == MachProjNode::fat_proj ) {
2458 // Fat-proj kills a slew of registers
2459 RegMask rm = n->out_RegMask();// Make local copy
2460 while( rm.is_NotEmpty() ) {
2461 OptoReg::Name kill = rm.find_first_elem();
2462 rm.Remove(kill);
2463 verify_do_def( n, kill, msg );
2464 }
2465 } else if( n_op != Op_Node ) { // Avoid brand new antidependence nodes
2466 // Get DEF'd registers the normal way
2467 verify_do_def( n, _regalloc->get_reg_first(n), msg );
2468 verify_do_def( n, _regalloc->get_reg_second(n), msg );
2469 }
2470
2471 // Now make all USEs live
2472 for( uint i=1; i<n->req(); i++ ) {
2473 Node *def = n->in(i);
2474 assert(def != 0, "input edge required");
2475 OptoReg::Name reg_lo = _regalloc->get_reg_first(def);
2476 OptoReg::Name reg_hi = _regalloc->get_reg_second(def);
2477 if( OptoReg::is_valid(reg_lo) ) {
2478 assert(!_reg_node[reg_lo] || edge_from_to(_reg_node[reg_lo],def), msg);
2479 _reg_node.map(reg_lo,n);
2480 }
2481 if( OptoReg::is_valid(reg_hi) ) {
2482 assert(!_reg_node[reg_hi] || edge_from_to(_reg_node[reg_hi],def), msg);
2483 _reg_node.map(reg_hi,n);
2484 }
2485 }
2486
2487 }
2488
2489 // Zap to something reasonable for the Antidependence code
2490 _reg_node.clear();
2491 }
2492 #endif
2493
2494 // Conditionally add precedence edges. Avoid putting edges on Projs.
2495 static void add_prec_edge_from_to( Node *from, Node *to ) {
2496 if( from->is_Proj() ) { // Put precedence edge on Proj's input
2497 assert( from->req() == 1 && (from->len() == 1 || from->in(1)==0), "no precedence edges on projections" );
2498 from = from->in(0);
2499 }
2500 if( from != to && // No cycles (for things like LD L0,[L0+4] )
2501 !edge_from_to( from, to ) ) // Avoid duplicate edge
2502 from->add_prec(to);
2503 }
2504
2505 //------------------------------anti_do_def------------------------------------
2506 void Scheduling::anti_do_def( Block *b, Node *def, OptoReg::Name def_reg, int is_def ) {
2507 if( !OptoReg::is_valid(def_reg) ) // Ignore stores & control flow
2508 return;
2509
2510 Node *pinch = _reg_node[def_reg]; // Get pinch point
2511 if( !pinch || _bbs[pinch->_idx] != b || // No pinch-point yet?
2512 is_def ) { // Check for a true def (not a kill)
2513 _reg_node.map(def_reg,def); // Record def/kill as the optimistic pinch-point
2514 return;
2515 }
2516
2517 Node *kill = def; // Rename 'def' to more descriptive 'kill'
2518 debug_only( def = (Node*)0xdeadbeef; )
2519
2520 // After some number of kills there _may_ be a later def
2521 Node *later_def = NULL;
2522
2523 // Finding a kill requires a real pinch-point.
2524 // Check for not already having a pinch-point.
2525 // Pinch points are Op_Node's.
2526 if( pinch->Opcode() != Op_Node ) { // Or later-def/kill as pinch-point?
2527 later_def = pinch; // Must be def/kill as optimistic pinch-point
2528 if ( _pinch_free_list.size() > 0) {
2529 pinch = _pinch_free_list.pop();
2530 } else {
2531 pinch = new (_cfg->C, 1) Node(1); // Pinch point to-be
2532 }
2533 if (pinch->_idx >= _regalloc->node_regs_max_index()) {
2534 _cfg->C->record_method_not_compilable("too many D-U pinch points");
2535 return;
2536 }
2537 _bbs.map(pinch->_idx,b); // Pretend it's valid in this block (lazy init)
2538 _reg_node.map(def_reg,pinch); // Record pinch-point
2539 //_regalloc->set_bad(pinch->_idx); // Already initialized this way.
2540 if( later_def->outcnt() == 0 || later_def->ideal_reg() == MachProjNode::fat_proj ) { // Distinguish def from kill
2541 pinch->init_req(0, _cfg->C->top()); // set not NULL for the next call
2542 add_prec_edge_from_to(later_def,pinch); // Add edge from kill to pinch
2543 later_def = NULL; // and no later def
2544 }
2545 pinch->set_req(0,later_def); // Hook later def so we can find it
2546 } else { // Else have valid pinch point
2547 if( pinch->in(0) ) // If there is a later-def
2548 later_def = pinch->in(0); // Get it
2549 }
2550
2551 // Add output-dependence edge from later def to kill
2552 if( later_def ) // If there is some original def
2553 add_prec_edge_from_to(later_def,kill); // Add edge from def to kill
2554
2555 // See if current kill is also a use, and so is forced to be the pinch-point.
2556 if( pinch->Opcode() == Op_Node ) {
2557 Node *uses = kill->is_Proj() ? kill->in(0) : kill;
2558 for( uint i=1; i<uses->req(); i++ ) {
2559 if( _regalloc->get_reg_first(uses->in(i)) == def_reg ||
2560 _regalloc->get_reg_second(uses->in(i)) == def_reg ) {
2561 // Yes, found a use/kill pinch-point
2562 pinch->set_req(0,NULL); //
2563 pinch->replace_by(kill); // Move anti-dep edges up
2564 pinch = kill;
2565 _reg_node.map(def_reg,pinch);
2566 return;
2567 }
2568 }
2569 }
2570
2571 // Add edge from kill to pinch-point
2572 add_prec_edge_from_to(kill,pinch);
2573 }
2574
2575 //------------------------------anti_do_use------------------------------------
2576 void Scheduling::anti_do_use( Block *b, Node *use, OptoReg::Name use_reg ) {
2577 if( !OptoReg::is_valid(use_reg) ) // Ignore stores & control flow
2578 return;
2579 Node *pinch = _reg_node[use_reg]; // Get pinch point
2580 // Check for no later def_reg/kill in block
2581 if( pinch && _bbs[pinch->_idx] == b &&
2582 // Use has to be block-local as well
2583 _bbs[use->_idx] == b ) {
2584 if( pinch->Opcode() == Op_Node && // Real pinch-point (not optimistic?)
2585 pinch->req() == 1 ) { // pinch not yet in block?
2586 pinch->del_req(0); // yank pointer to later-def, also set flag
2587 // Insert the pinch-point in the block just after the last use
2588 b->_nodes.insert(b->find_node(use)+1,pinch);
2589 _bb_end++; // Increase size scheduled region in block
2590 }
2591
2592 add_prec_edge_from_to(pinch,use);
2593 }
2594 }
2595
2596 //------------------------------ComputeRegisterAntidependences-----------------
2597 // We insert antidependences between the reads and following write of
2598 // allocated registers to prevent illegal code motion. Hopefully, the
2599 // number of added references should be fairly small, especially as we
2600 // are only adding references within the current basic block.
2601 void Scheduling::ComputeRegisterAntidependencies(Block *b) {
2602
2603 #ifdef ASSERT
2604 verify_good_schedule(b,"before block local scheduling");
2605 #endif
2606
2607 // A valid schedule, for each register independently, is an endless cycle
2608 // of: a def, then some uses (connected to the def by true dependencies),
2609 // then some kills (defs with no uses), finally the cycle repeats with a new
2610 // def. The uses are allowed to float relative to each other, as are the
2611 // kills. No use is allowed to slide past a kill (or def). This requires
2612 // antidependencies between all uses of a single def and all kills that
2613 // follow, up to the next def. More edges are redundant, because later defs
2614 // & kills are already serialized with true or antidependencies. To keep
2615 // the edge count down, we add a 'pinch point' node if there's more than
2616 // one use or more than one kill/def.
2617
2618 // We add dependencies in one bottom-up pass.
2619
2620 // For each instruction we handle it's DEFs/KILLs, then it's USEs.
2621
2622 // For each DEF/KILL, we check to see if there's a prior DEF/KILL for this
2623 // register. If not, we record the DEF/KILL in _reg_node, the
2624 // register-to-def mapping. If there is a prior DEF/KILL, we insert a
2625 // "pinch point", a new Node that's in the graph but not in the block.
2626 // We put edges from the prior and current DEF/KILLs to the pinch point.
2627 // We put the pinch point in _reg_node. If there's already a pinch point
2628 // we merely add an edge from the current DEF/KILL to the pinch point.
2629
2630 // After doing the DEF/KILLs, we handle USEs. For each used register, we
2631 // put an edge from the pinch point to the USE.
2632
2633 // To be expedient, the _reg_node array is pre-allocated for the whole
2634 // compilation. _reg_node is lazily initialized; it either contains a NULL,
2635 // or a valid def/kill/pinch-point, or a leftover node from some prior
2636 // block. Leftover node from some prior block is treated like a NULL (no
2637 // prior def, so no anti-dependence needed). Valid def is distinguished by
2638 // it being in the current block.
2639 bool fat_proj_seen = false;
2640 uint last_safept = _bb_end-1;
2641 Node* end_node = (_bb_end-1 >= _bb_start) ? b->_nodes[last_safept] : NULL;
2642 Node* last_safept_node = end_node;
2643 for( uint i = _bb_end-1; i >= _bb_start; i-- ) {
2644 Node *n = b->_nodes[i];
2645 int is_def = n->outcnt(); // def if some uses prior to adding precedence edges
2646 if( n->Opcode() == Op_MachProj && n->ideal_reg() == MachProjNode::fat_proj ) {
2647 // Fat-proj kills a slew of registers
2648 // This can add edges to 'n' and obscure whether or not it was a def,
2649 // hence the is_def flag.
2650 fat_proj_seen = true;
2651 RegMask rm = n->out_RegMask();// Make local copy
2652 while( rm.is_NotEmpty() ) {
2653 OptoReg::Name kill = rm.find_first_elem();
2654 rm.Remove(kill);
2655 anti_do_def( b, n, kill, is_def );
2656 }
2657 } else {
2658 // Get DEF'd registers the normal way
2659 anti_do_def( b, n, _regalloc->get_reg_first(n), is_def );
2660 anti_do_def( b, n, _regalloc->get_reg_second(n), is_def );
2661 }
2662
2663 // Check each register used by this instruction for a following DEF/KILL
2664 // that must occur afterward and requires an anti-dependence edge.
2665 for( uint j=0; j<n->req(); j++ ) {
2666 Node *def = n->in(j);
2667 if( def ) {
2668 assert( def->Opcode() != Op_MachProj || def->ideal_reg() != MachProjNode::fat_proj, "" );
2669 anti_do_use( b, n, _regalloc->get_reg_first(def) );
2670 anti_do_use( b, n, _regalloc->get_reg_second(def) );
2671 }
2672 }
2673 // Do not allow defs of new derived values to float above GC
2674 // points unless the base is definitely available at the GC point.
2675
2676 Node *m = b->_nodes[i];
2677
2678 // Add precedence edge from following safepoint to use of derived pointer
2679 if( last_safept_node != end_node &&
2680 m != last_safept_node) {
2681 for (uint k = 1; k < m->req(); k++) {
2682 const Type *t = m->in(k)->bottom_type();
2683 if( t->isa_oop_ptr() &&
2684 t->is_ptr()->offset() != 0 ) {
2685 last_safept_node->add_prec( m );
2686 break;
2687 }
2688 }
2689 }
2690
2691 if( n->jvms() ) { // Precedence edge from derived to safept
2692 // Check if last_safept_node was moved by pinch-point insertion in anti_do_use()
2693 if( b->_nodes[last_safept] != last_safept_node ) {
2694 last_safept = b->find_node(last_safept_node);
2695 }
2696 for( uint j=last_safept; j > i; j-- ) {
2697 Node *mach = b->_nodes[j];
2698 if( mach->is_Mach() && mach->as_Mach()->ideal_Opcode() == Op_AddP )
2699 mach->add_prec( n );
2700 }
2701 last_safept = i;
2702 last_safept_node = m;
2703 }
2704 }
2705
2706 if (fat_proj_seen) {
2707 // Garbage collect pinch nodes that were not consumed.
2708 // They are usually created by a fat kill MachProj for a call.
2709 garbage_collect_pinch_nodes();
2710 }
2711 }
2712
2713 //------------------------------garbage_collect_pinch_nodes-------------------------------
2714
2715 // Garbage collect pinch nodes for reuse by other blocks.
2716 //
2717 // The block scheduler's insertion of anti-dependence
2718 // edges creates many pinch nodes when the block contains
2719 // 2 or more Calls. A pinch node is used to prevent a
2720 // combinatorial explosion of edges. If a set of kills for a
2721 // register is anti-dependent on a set of uses (or defs), rather
2722 // than adding an edge in the graph between each pair of kill
2723 // and use (or def), a pinch is inserted between them:
2724 //
2725 // use1 use2 use3
2726 // \ | /
2727 // \ | /
2728 // pinch
2729 // / | \
2730 // / | \
2731 // kill1 kill2 kill3
2732 //
2733 // One pinch node is created per register killed when
2734 // the second call is encountered during a backwards pass
2735 // over the block. Most of these pinch nodes are never
2736 // wired into the graph because the register is never
2737 // used or def'ed in the block.
2738 //
2739 void Scheduling::garbage_collect_pinch_nodes() {
2740 #ifndef PRODUCT
2741 if (_cfg->C->trace_opto_output()) tty->print("Reclaimed pinch nodes:");
2742 #endif
2743 int trace_cnt = 0;
2744 for (uint k = 0; k < _reg_node.Size(); k++) {
2745 Node* pinch = _reg_node[k];
2746 if (pinch != NULL && pinch->Opcode() == Op_Node &&
2747 // no predecence input edges
2748 (pinch->req() == pinch->len() || pinch->in(pinch->req()) == NULL) ) {
2749 cleanup_pinch(pinch);
2750 _pinch_free_list.push(pinch);
2751 _reg_node.map(k, NULL);
2752 #ifndef PRODUCT
2753 if (_cfg->C->trace_opto_output()) {
2754 trace_cnt++;
2755 if (trace_cnt > 40) {
2756 tty->print("\n");
2757 trace_cnt = 0;
2758 }
2759 tty->print(" %d", pinch->_idx);
2760 }
2761 #endif
2762 }
2763 }
2764 #ifndef PRODUCT
2765 if (_cfg->C->trace_opto_output()) tty->print("\n");
2766 #endif
2767 }
2768
2769 // Clean up a pinch node for reuse.
2770 void Scheduling::cleanup_pinch( Node *pinch ) {
2771 assert (pinch && pinch->Opcode() == Op_Node && pinch->req() == 1, "just checking");
2772
2773 for (DUIterator_Last imin, i = pinch->last_outs(imin); i >= imin; ) {
2774 Node* use = pinch->last_out(i);
2775 uint uses_found = 0;
2776 for (uint j = use->req(); j < use->len(); j++) {
2777 if (use->in(j) == pinch) {
2778 use->rm_prec(j);
2779 uses_found++;
2780 }
2781 }
2782 assert(uses_found > 0, "must be a precedence edge");
2783 i -= uses_found; // we deleted 1 or more copies of this edge
2784 }
2785 // May have a later_def entry
2786 pinch->set_req(0, NULL);
2787 }
2788
2789 //------------------------------print_statistics-------------------------------
2790 #ifndef PRODUCT
2791
2792 void Scheduling::dump_available() const {
2793 tty->print("#Availist ");
2794 for (uint i = 0; i < _available.size(); i++)
2795 tty->print(" N%d/l%d", _available[i]->_idx,_current_latency[_available[i]->_idx]);
2796 tty->cr();
2797 }
2798
2799 // Print Scheduling Statistics
2800 void Scheduling::print_statistics() {
2801 // Print the size added by nops for bundling
2802 tty->print("Nops added %d bytes to total of %d bytes",
2803 _total_nop_size, _total_method_size);
2804 if (_total_method_size > 0)
2805 tty->print(", for %.2f%%",
2806 ((double)_total_nop_size) / ((double) _total_method_size) * 100.0);
2807 tty->print("\n");
2808
2809 // Print the number of branch shadows filled
2810 if (Pipeline::_branch_has_delay_slot) {
2811 tty->print("Of %d branches, %d had unconditional delay slots filled",
2812 _total_branches, _total_unconditional_delays);
2813 if (_total_branches > 0)
2814 tty->print(", for %.2f%%",
2815 ((double)_total_unconditional_delays) / ((double)_total_branches) * 100.0);
2816 tty->print("\n");
2817 }
2818
2819 uint total_instructions = 0, total_bundles = 0;
2820
2821 for (uint i = 1; i <= Pipeline::_max_instrs_per_cycle; i++) {
2822 uint bundle_count = _total_instructions_per_bundle[i];
2823 total_instructions += bundle_count * i;
2824 total_bundles += bundle_count;
2825 }
2826
2827 if (total_bundles > 0)
2828 tty->print("Average ILP (excluding nops) is %.2f\n",
2829 ((double)total_instructions) / ((double)total_bundles));
2830 }
2831 #endif