1 /*
2 * Copyright 1998-2009 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any 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 // Initialize the space for the BufferBlob used to find and verify
49 // instruction size in MachNode::emit_size()
50 init_scratch_buffer_blob();
51 if (failing()) return; // Out of memory
52
53 // The number of new nodes (mostly MachNop) is proportional to
54 // the number of java calls and inner loops which are aligned.
55 if ( C->check_node_count((NodeLimitFudgeFactor + C->java_calls()*3 +
56 C->inner_loops()*(OptoLoopAlignment-1)),
57 "out of nodes before code generation" ) ) {
58 return;
59 }
60 // Make sure I can find the Start Node
61 Block_Array& bbs = _cfg->_bbs;
62 Block *entry = _cfg->_blocks[1];
63 Block *broot = _cfg->_broot;
64
65 const StartNode *start = entry->_nodes[0]->as_Start();
66
67 // Replace StartNode with prolog
68 MachPrologNode *prolog = new (this) MachPrologNode();
69 entry->_nodes.map( 0, prolog );
70 bbs.map( prolog->_idx, entry );
71 bbs.map( start->_idx, NULL ); // start is no longer in any block
72
73 // Virtual methods need an unverified entry point
74
75 if( is_osr_compilation() ) {
76 if( PoisonOSREntry ) {
77 // TODO: Should use a ShouldNotReachHereNode...
78 _cfg->insert( broot, 0, new (this) MachBreakpointNode() );
79 }
80 } else {
81 if( _method && !_method->flags().is_static() ) {
82 // Insert unvalidated entry point
83 _cfg->insert( broot, 0, new (this) MachUEPNode() );
84 }
85
86 }
87
88
89 // Break before main entry point
90 if( (_method && _method->break_at_execute())
91 #ifndef PRODUCT
92 ||(OptoBreakpoint && is_method_compilation())
93 ||(OptoBreakpointOSR && is_osr_compilation())
94 ||(OptoBreakpointC2R && !_method)
95 #endif
96 ) {
97 // checking for _method means that OptoBreakpoint does not apply to
98 // runtime stubs or frame converters
99 _cfg->insert( entry, 1, new (this) MachBreakpointNode() );
100 }
101
102 // Insert epilogs before every return
103 for( uint i=0; i<_cfg->_num_blocks; i++ ) {
104 Block *b = _cfg->_blocks[i];
105 if( !b->is_connector() && b->non_connector_successor(0) == _cfg->_broot ) { // Found a program exit point?
106 Node *m = b->end();
107 if( m->is_Mach() && m->as_Mach()->ideal_Opcode() != Op_Halt ) {
108 MachEpilogNode *epilog = new (this) MachEpilogNode(m->as_Mach()->ideal_Opcode() == Op_Return);
109 b->add_inst( epilog );
110 bbs.map(epilog->_idx, b);
111 //_regalloc->set_bad(epilog->_idx); // Already initialized this way.
112 }
113 }
114 }
115
116 # ifdef ENABLE_ZAP_DEAD_LOCALS
117 if ( ZapDeadCompiledLocals ) Insert_zap_nodes();
118 # endif
119
120 ScheduleAndBundle();
121
122 #ifndef PRODUCT
123 if (trace_opto_output()) {
124 tty->print("\n---- After ScheduleAndBundle ----\n");
125 for (uint i = 0; i < _cfg->_num_blocks; i++) {
126 tty->print("\nBB#%03d:\n", i);
127 Block *bb = _cfg->_blocks[i];
128 for (uint j = 0; j < bb->_nodes.size(); j++) {
129 Node *n = bb->_nodes[j];
130 OptoReg::Name reg = _regalloc->get_reg_first(n);
131 tty->print(" %-6s ", reg >= 0 && reg < REG_COUNT ? Matcher::regName[reg] : "");
132 n->dump();
133 }
134 }
135 }
136 #endif
137
138 if (failing()) return;
139
140 BuildOopMaps();
141
142 if (failing()) return;
143
144 Fill_buffer();
145 }
146
147 bool Compile::need_stack_bang(int frame_size_in_bytes) const {
148 // Determine if we need to generate a stack overflow check.
149 // Do it if the method is not a stub function and
150 // has java calls or has frame size > vm_page_size/8.
151 return (stub_function() == NULL &&
152 (has_java_calls() || frame_size_in_bytes > os::vm_page_size()>>3));
153 }
154
155 bool Compile::need_register_stack_bang() const {
156 // Determine if we need to generate a register stack overflow check.
157 // This is only used on architectures which have split register
158 // and memory stacks (ie. IA64).
159 // Bang if the method is not a stub function and has java calls
160 return (stub_function() == NULL && has_java_calls());
161 }
162
163 # ifdef ENABLE_ZAP_DEAD_LOCALS
164
165
166 // In order to catch compiler oop-map bugs, we have implemented
167 // a debugging mode called ZapDeadCompilerLocals.
168 // This mode causes the compiler to insert a call to a runtime routine,
169 // "zap_dead_locals", right before each place in compiled code
170 // that could potentially be a gc-point (i.e., a safepoint or oop map point).
171 // The runtime routine checks that locations mapped as oops are really
172 // oops, that locations mapped as values do not look like oops,
173 // and that locations mapped as dead are not used later
174 // (by zapping them to an invalid address).
175
176 int Compile::_CompiledZap_count = 0;
177
178 void Compile::Insert_zap_nodes() {
179 bool skip = false;
180
181
182 // Dink with static counts because code code without the extra
183 // runtime calls is MUCH faster for debugging purposes
184
185 if ( CompileZapFirst == 0 ) ; // nothing special
186 else if ( CompileZapFirst > CompiledZap_count() ) skip = true;
187 else if ( CompileZapFirst == CompiledZap_count() )
188 warning("starting zap compilation after skipping");
189
190 if ( CompileZapLast == -1 ) ; // nothing special
191 else if ( CompileZapLast < CompiledZap_count() ) skip = true;
192 else if ( CompileZapLast == CompiledZap_count() )
193 warning("about to compile last zap");
194
195 ++_CompiledZap_count; // counts skipped zaps, too
196
197 if ( skip ) return;
198
199
200 if ( _method == NULL )
201 return; // no safepoints/oopmaps emitted for calls in stubs,so we don't care
202
203 // Insert call to zap runtime stub before every node with an oop map
204 for( uint i=0; i<_cfg->_num_blocks; i++ ) {
205 Block *b = _cfg->_blocks[i];
206 for ( uint j = 0; j < b->_nodes.size(); ++j ) {
207 Node *n = b->_nodes[j];
208
209 // Determining if we should insert a zap-a-lot node in output.
210 // We do that for all nodes that has oopmap info, except for calls
211 // to allocation. Calls to allocation passes in the old top-of-eden pointer
212 // and expect the C code to reset it. Hence, there can be no safepoints between
213 // the inlined-allocation and the call to new_Java, etc.
214 // We also cannot zap monitor calls, as they must hold the microlock
215 // during the call to Zap, which also wants to grab the microlock.
216 bool insert = n->is_MachSafePoint() && (n->as_MachSafePoint()->oop_map() != NULL);
217 if ( insert ) { // it is MachSafePoint
218 if ( !n->is_MachCall() ) {
219 insert = false;
220 } else if ( n->is_MachCall() ) {
221 MachCallNode* call = n->as_MachCall();
222 if (call->entry_point() == OptoRuntime::new_instance_Java() ||
223 call->entry_point() == OptoRuntime::new_array_Java() ||
224 call->entry_point() == OptoRuntime::multianewarray2_Java() ||
225 call->entry_point() == OptoRuntime::multianewarray3_Java() ||
226 call->entry_point() == OptoRuntime::multianewarray4_Java() ||
227 call->entry_point() == OptoRuntime::multianewarray5_Java() ||
228 call->entry_point() == OptoRuntime::slow_arraycopy_Java() ||
229 call->entry_point() == OptoRuntime::complete_monitor_locking_Java()
230 ) {
231 insert = false;
232 }
233 }
234 if (insert) {
235 Node *zap = call_zap_node(n->as_MachSafePoint(), i);
236 b->_nodes.insert( j, zap );
237 _cfg->_bbs.map( zap->_idx, b );
238 ++j;
239 }
240 }
241 }
242 }
243 }
244
245
246 Node* Compile::call_zap_node(MachSafePointNode* node_to_check, int block_no) {
247 const TypeFunc *tf = OptoRuntime::zap_dead_locals_Type();
248 CallStaticJavaNode* ideal_node =
249 new (this, tf->domain()->cnt()) CallStaticJavaNode( tf,
250 OptoRuntime::zap_dead_locals_stub(_method->flags().is_native()),
251 "call zap dead locals stub", 0, TypePtr::BOTTOM);
252 // We need to copy the OopMap from the site we're zapping at.
253 // We have to make a copy, because the zap site might not be
254 // a call site, and zap_dead is a call site.
255 OopMap* clone = node_to_check->oop_map()->deep_copy();
256
257 // Add the cloned OopMap to the zap node
258 ideal_node->set_oop_map(clone);
259 return _matcher->match_sfpt(ideal_node);
260 }
261
262 //------------------------------is_node_getting_a_safepoint--------------------
263 bool Compile::is_node_getting_a_safepoint( Node* n) {
264 // This code duplicates the logic prior to the call of add_safepoint
265 // below in this file.
266 if( n->is_MachSafePoint() ) return true;
267 return false;
268 }
269
270 # endif // ENABLE_ZAP_DEAD_LOCALS
271
272 //------------------------------compute_loop_first_inst_sizes------------------
273 // Compute the size of first NumberOfLoopInstrToAlign instructions at the top
274 // of a loop. When aligning a loop we need to provide enough instructions
275 // in cpu's fetch buffer to feed decoders. The loop alignment could be
276 // avoided if we have enough instructions in fetch buffer at the head of a loop.
277 // By default, the size is set to 999999 by Block's constructor so that
278 // a loop will be aligned if the size is not reset here.
279 //
280 // Note: Mach instructions could contain several HW instructions
281 // so the size is estimated only.
282 //
283 void Compile::compute_loop_first_inst_sizes() {
284 // The next condition is used to gate the loop alignment optimization.
285 // Don't aligned a loop if there are enough instructions at the head of a loop
286 // or alignment padding is larger then MaxLoopPad. By default, MaxLoopPad
287 // is equal to OptoLoopAlignment-1 except on new Intel cpus, where it is
288 // equal to 11 bytes which is the largest address NOP instruction.
289 if( MaxLoopPad < OptoLoopAlignment-1 ) {
290 uint last_block = _cfg->_num_blocks-1;
291 for( uint i=1; i <= last_block; i++ ) {
292 Block *b = _cfg->_blocks[i];
293 // Check the first loop's block which requires an alignment.
294 if( b->loop_alignment() > (uint)relocInfo::addr_unit() ) {
295 uint sum_size = 0;
296 uint inst_cnt = NumberOfLoopInstrToAlign;
297 inst_cnt = b->compute_first_inst_size(sum_size, inst_cnt, _regalloc);
298
299 // Check subsequent fallthrough blocks if the loop's first
300 // block(s) does not have enough instructions.
301 Block *nb = b;
302 while( inst_cnt > 0 &&
303 i < last_block &&
304 !_cfg->_blocks[i+1]->has_loop_alignment() &&
305 !nb->has_successor(b) ) {
306 i++;
307 nb = _cfg->_blocks[i];
308 inst_cnt = nb->compute_first_inst_size(sum_size, inst_cnt, _regalloc);
309 } // while( inst_cnt > 0 && i < last_block )
310
311 b->set_first_inst_size(sum_size);
312 } // f( b->head()->is_Loop() )
313 } // for( i <= last_block )
314 } // if( MaxLoopPad < OptoLoopAlignment-1 )
315 }
316
317 //----------------------Shorten_branches---------------------------------------
318 // The architecture description provides short branch variants for some long
319 // branch instructions. Replace eligible long branches with short branches.
320 void Compile::Shorten_branches(Label *labels, int& code_size, int& reloc_size, int& stub_size, int& const_size) {
321
322 // fill in the nop array for bundling computations
323 MachNode *_nop_list[Bundle::_nop_count];
324 Bundle::initialize_nops(_nop_list, this);
325
326 // ------------------
327 // Compute size of each block, method size, and relocation information size
328 uint *jmp_end = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks);
329 uint *blk_starts = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks+1);
330 DEBUG_ONLY( uint *jmp_target = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks); )
331 DEBUG_ONLY( uint *jmp_rule = NEW_RESOURCE_ARRAY(uint,_cfg->_num_blocks); )
332 blk_starts[0] = 0;
333
334 // Initialize the sizes to 0
335 code_size = 0; // Size in bytes of generated code
336 stub_size = 0; // Size in bytes of all stub entries
337 // Size in bytes of all relocation entries, including those in local stubs.
338 // Start with 2-bytes of reloc info for the unvalidated entry point
339 reloc_size = 1; // Number of relocation entries
340 const_size = 0; // size of fp constants in words
341
342 // Make three passes. The first computes pessimistic blk_starts,
343 // relative jmp_end, reloc_size and const_size information.
344 // The second performs short branch substitution using the pessimistic
345 // sizing. The third inserts nops where needed.
346
347 Node *nj; // tmp
348
349 // Step one, perform a pessimistic sizing pass.
350 uint i;
351 uint min_offset_from_last_call = 1; // init to a positive value
352 uint nop_size = (new (this) MachNopNode())->size(_regalloc);
353 for( i=0; i<_cfg->_num_blocks; i++ ) { // For all blocks
354 Block *b = _cfg->_blocks[i];
355
356 // Sum all instruction sizes to compute block size
357 uint last_inst = b->_nodes.size();
358 uint blk_size = 0;
359 for( uint j = 0; j<last_inst; j++ ) {
360 nj = b->_nodes[j];
361 uint inst_size = nj->size(_regalloc);
362 blk_size += inst_size;
363 // Handle machine instruction nodes
364 if( nj->is_Mach() ) {
365 MachNode *mach = nj->as_Mach();
366 blk_size += (mach->alignment_required() - 1) * relocInfo::addr_unit(); // assume worst case padding
367 reloc_size += mach->reloc();
368 const_size += mach->const_size();
369 if( mach->is_MachCall() ) {
370 MachCallNode *mcall = mach->as_MachCall();
371 // This destination address is NOT PC-relative
372
373 mcall->method_set((intptr_t)mcall->entry_point());
374
375 if( mcall->is_MachCallJava() && mcall->as_MachCallJava()->_method ) {
376 stub_size += size_java_to_interp();
377 reloc_size += reloc_java_to_interp();
378 }
379 } else if (mach->is_MachSafePoint()) {
380 // If call/safepoint are adjacent, account for possible
381 // nop to disambiguate the two safepoints.
382 if (min_offset_from_last_call == 0) {
383 blk_size += nop_size;
384 }
385 }
386 }
387 min_offset_from_last_call += inst_size;
388 // Remember end of call offset
389 if (nj->is_MachCall() && nj->as_MachCall()->is_safepoint_node()) {
390 min_offset_from_last_call = 0;
391 }
392 }
393
394 // During short branch replacement, we store the relative (to blk_starts)
395 // end of jump in jmp_end, rather than the absolute end of jump. This
396 // is so that we do not need to recompute sizes of all nodes when we compute
397 // correct blk_starts in our next sizing pass.
398 jmp_end[i] = blk_size;
399 DEBUG_ONLY( jmp_target[i] = 0; )
400
401 // When the next block starts a loop, we may insert pad NOP
402 // instructions. Since we cannot know our future alignment,
403 // assume the worst.
404 if( i<_cfg->_num_blocks-1 ) {
405 Block *nb = _cfg->_blocks[i+1];
406 int max_loop_pad = nb->code_alignment()-relocInfo::addr_unit();
407 if( max_loop_pad > 0 ) {
408 assert(is_power_of_2(max_loop_pad+relocInfo::addr_unit()), "");
409 blk_size += max_loop_pad;
410 }
411 }
412
413 // Save block size; update total method size
414 blk_starts[i+1] = blk_starts[i]+blk_size;
415 }
416
417 // Step two, replace eligible long jumps.
418
419 // Note: this will only get the long branches within short branch
420 // range. Another pass might detect more branches that became
421 // candidates because the shortening in the first pass exposed
422 // more opportunities. Unfortunately, this would require
423 // recomputing the starting and ending positions for the blocks
424 for( i=0; i<_cfg->_num_blocks; i++ ) {
425 Block *b = _cfg->_blocks[i];
426
427 int j;
428 // Find the branch; ignore trailing NOPs.
429 for( j = b->_nodes.size()-1; j>=0; j-- ) {
430 nj = b->_nodes[j];
431 if( !nj->is_Mach() || nj->as_Mach()->ideal_Opcode() != Op_Con )
432 break;
433 }
434
435 if (j >= 0) {
436 if( nj->is_Mach() && nj->as_Mach()->may_be_short_branch() ) {
437 MachNode *mach = nj->as_Mach();
438 // This requires the TRUE branch target be in succs[0]
439 uint bnum = b->non_connector_successor(0)->_pre_order;
440 uintptr_t target = blk_starts[bnum];
441 if( mach->is_pc_relative() ) {
442 int offset = target-(blk_starts[i] + jmp_end[i]);
443 if (_matcher->is_short_branch_offset(mach->rule(), offset)) {
444 // We've got a winner. Replace this branch.
445 MachNode* replacement = mach->short_branch_version(this);
446 b->_nodes.map(j, replacement);
447 mach->subsume_by(replacement);
448
449 // Update the jmp_end size to save time in our
450 // next pass.
451 jmp_end[i] -= (mach->size(_regalloc) - replacement->size(_regalloc));
452 DEBUG_ONLY( jmp_target[i] = bnum; );
453 DEBUG_ONLY( jmp_rule[i] = mach->rule(); );
454 }
455 } else {
456 #ifndef PRODUCT
457 mach->dump(3);
458 #endif
459 Unimplemented();
460 }
461 }
462 }
463 }
464
465 // Compute the size of first NumberOfLoopInstrToAlign instructions at head
466 // of a loop. It is used to determine the padding for loop alignment.
467 compute_loop_first_inst_sizes();
468
469 // Step 3, compute the offsets of all the labels
470 uint last_call_adr = max_uint;
471 for( i=0; i<_cfg->_num_blocks; i++ ) { // For all blocks
472 // copy the offset of the beginning to the corresponding label
473 assert(labels[i].is_unused(), "cannot patch at this point");
474 labels[i].bind_loc(blk_starts[i], CodeBuffer::SECT_INSTS);
475
476 // insert padding for any instructions that need it
477 Block *b = _cfg->_blocks[i];
478 uint last_inst = b->_nodes.size();
479 uint adr = blk_starts[i];
480 for( uint j = 0; j<last_inst; j++ ) {
481 nj = b->_nodes[j];
482 if( nj->is_Mach() ) {
483 int padding = nj->as_Mach()->compute_padding(adr);
484 // If call/safepoint are adjacent insert a nop (5010568)
485 if (padding == 0 && nj->is_MachSafePoint() && !nj->is_MachCall() &&
486 adr == last_call_adr ) {
487 padding = nop_size;
488 }
489 if(padding > 0) {
490 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size");
491 int nops_cnt = padding / nop_size;
492 MachNode *nop = new (this) MachNopNode(nops_cnt);
493 b->_nodes.insert(j++, nop);
494 _cfg->_bbs.map( nop->_idx, b );
495 adr += padding;
496 last_inst++;
497 }
498 }
499 adr += nj->size(_regalloc);
500
501 // Remember end of call offset
502 if (nj->is_MachCall() && nj->as_MachCall()->is_safepoint_node()) {
503 last_call_adr = adr;
504 }
505 }
506
507 if ( i != _cfg->_num_blocks-1) {
508 // Get the size of the block
509 uint blk_size = adr - blk_starts[i];
510
511 // When the next block is the top of a loop, we may insert pad NOP
512 // instructions.
513 Block *nb = _cfg->_blocks[i+1];
514 int current_offset = blk_starts[i] + blk_size;
515 current_offset += nb->alignment_padding(current_offset);
516 // Save block size; update total method size
517 blk_starts[i+1] = current_offset;
518 }
519 }
520
521 #ifdef ASSERT
522 for( i=0; i<_cfg->_num_blocks; i++ ) { // For all blocks
523 if( jmp_target[i] != 0 ) {
524 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_end[i]);
525 if (!_matcher->is_short_branch_offset(jmp_rule[i], offset)) {
526 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]);
527 }
528 assert(_matcher->is_short_branch_offset(jmp_rule[i], offset), "Displacement too large for short jmp");
529 }
530 }
531 #endif
532
533 // ------------------
534 // Compute size for code buffer
535 code_size = blk_starts[i-1] + jmp_end[i-1];
536
537 // Relocation records
538 reloc_size += 1; // Relo entry for exception handler
539
540 // Adjust reloc_size to number of record of relocation info
541 // Min is 2 bytes, max is probably 6 or 8, with a tax up to 25% for
542 // a relocation index.
543 // The CodeBuffer will expand the locs array if this estimate is too low.
544 reloc_size *= 10 / sizeof(relocInfo);
545
546 // Adjust const_size to number of bytes
547 const_size *= 2*jintSize; // both float and double take two words per entry
548
549 }
550
551 //------------------------------FillLocArray-----------------------------------
552 // Create a bit of debug info and append it to the array. The mapping is from
553 // Java local or expression stack to constant, register or stack-slot. For
554 // doubles, insert 2 mappings and return 1 (to tell the caller that the next
555 // entry has been taken care of and caller should skip it).
556 static LocationValue *new_loc_value( PhaseRegAlloc *ra, OptoReg::Name regnum, Location::Type l_type ) {
557 // This should never have accepted Bad before
558 assert(OptoReg::is_valid(regnum), "location must be valid");
559 return (OptoReg::is_reg(regnum))
560 ? new LocationValue(Location::new_reg_loc(l_type, OptoReg::as_VMReg(regnum)) )
561 : new LocationValue(Location::new_stk_loc(l_type, ra->reg2offset(regnum)));
562 }
563
564
565 ObjectValue*
566 Compile::sv_for_node_id(GrowableArray<ScopeValue*> *objs, int id) {
567 for (int i = 0; i < objs->length(); i++) {
568 assert(objs->at(i)->is_object(), "corrupt object cache");
569 ObjectValue* sv = (ObjectValue*) objs->at(i);
570 if (sv->id() == id) {
571 return sv;
572 }
573 }
574 // Otherwise..
575 return NULL;
576 }
577
578 void Compile::set_sv_for_object_node(GrowableArray<ScopeValue*> *objs,
579 ObjectValue* sv ) {
580 assert(sv_for_node_id(objs, sv->id()) == NULL, "Precondition");
581 objs->append(sv);
582 }
583
584
585 void Compile::FillLocArray( int idx, MachSafePointNode* sfpt, Node *local,
586 GrowableArray<ScopeValue*> *array,
587 GrowableArray<ScopeValue*> *objs ) {
588 assert( local, "use _top instead of null" );
589 if (array->length() != idx) {
590 assert(array->length() == idx + 1, "Unexpected array count");
591 // Old functionality:
592 // return
593 // New functionality:
594 // Assert if the local is not top. In product mode let the new node
595 // override the old entry.
596 assert(local == top(), "LocArray collision");
597 if (local == top()) {
598 return;
599 }
600 array->pop();
601 }
602 const Type *t = local->bottom_type();
603
604 // Is it a safepoint scalar object node?
605 if (local->is_SafePointScalarObject()) {
606 SafePointScalarObjectNode* spobj = local->as_SafePointScalarObject();
607
608 ObjectValue* sv = Compile::sv_for_node_id(objs, spobj->_idx);
609 if (sv == NULL) {
610 ciKlass* cik = t->is_oopptr()->klass();
611 assert(cik->is_instance_klass() ||
612 cik->is_array_klass(), "Not supported allocation.");
613 sv = new ObjectValue(spobj->_idx,
614 new ConstantOopWriteValue(cik->constant_encoding()));
615 Compile::set_sv_for_object_node(objs, sv);
616
617 uint first_ind = spobj->first_index();
618 for (uint i = 0; i < spobj->n_fields(); i++) {
619 Node* fld_node = sfpt->in(first_ind+i);
620 (void)FillLocArray(sv->field_values()->length(), sfpt, fld_node, sv->field_values(), objs);
621 }
622 }
623 array->append(sv);
624 return;
625 }
626
627 // Grab the register number for the local
628 OptoReg::Name regnum = _regalloc->get_reg_first(local);
629 if( OptoReg::is_valid(regnum) ) {// Got a register/stack?
630 // Record the double as two float registers.
631 // The register mask for such a value always specifies two adjacent
632 // float registers, with the lower register number even.
633 // Normally, the allocation of high and low words to these registers
634 // is irrelevant, because nearly all operations on register pairs
635 // (e.g., StoreD) treat them as a single unit.
636 // Here, we assume in addition that the words in these two registers
637 // stored "naturally" (by operations like StoreD and double stores
638 // within the interpreter) such that the lower-numbered register
639 // is written to the lower memory address. This may seem like
640 // a machine dependency, but it is not--it is a requirement on
641 // the author of the <arch>.ad file to ensure that, for every
642 // even/odd double-register pair to which a double may be allocated,
643 // the word in the even single-register is stored to the first
644 // memory word. (Note that register numbers are completely
645 // arbitrary, and are not tied to any machine-level encodings.)
646 #ifdef _LP64
647 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon ) {
648 array->append(new ConstantIntValue(0));
649 array->append(new_loc_value( _regalloc, regnum, Location::dbl ));
650 } else if ( t->base() == Type::Long ) {
651 array->append(new ConstantIntValue(0));
652 array->append(new_loc_value( _regalloc, regnum, Location::lng ));
653 } else if ( t->base() == Type::RawPtr ) {
654 // jsr/ret return address which must be restored into a the full
655 // width 64-bit stack slot.
656 array->append(new_loc_value( _regalloc, regnum, Location::lng ));
657 }
658 #else //_LP64
659 #ifdef SPARC
660 if (t->base() == Type::Long && OptoReg::is_reg(regnum)) {
661 // For SPARC we have to swap high and low words for
662 // long values stored in a single-register (g0-g7).
663 array->append(new_loc_value( _regalloc, regnum , Location::normal ));
664 array->append(new_loc_value( _regalloc, OptoReg::add(regnum,1), Location::normal ));
665 } else
666 #endif //SPARC
667 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon || t->base() == Type::Long ) {
668 // Repack the double/long as two jints.
669 // The convention the interpreter uses is that the second local
670 // holds the first raw word of the native double representation.
671 // This is actually reasonable, since locals and stack arrays
672 // grow downwards in all implementations.
673 // (If, on some machine, the interpreter's Java locals or stack
674 // were to grow upwards, the embedded doubles would be word-swapped.)
675 array->append(new_loc_value( _regalloc, OptoReg::add(regnum,1), Location::normal ));
676 array->append(new_loc_value( _regalloc, regnum , Location::normal ));
677 }
678 #endif //_LP64
679 else if( (t->base() == Type::FloatBot || t->base() == Type::FloatCon) &&
680 OptoReg::is_reg(regnum) ) {
681 array->append(new_loc_value( _regalloc, regnum, Matcher::float_in_double
682 ? Location::float_in_dbl : Location::normal ));
683 } else if( t->base() == Type::Int && OptoReg::is_reg(regnum) ) {
684 array->append(new_loc_value( _regalloc, regnum, Matcher::int_in_long
685 ? Location::int_in_long : Location::normal ));
686 } else if( t->base() == Type::NarrowOop ) {
687 array->append(new_loc_value( _regalloc, regnum, Location::narrowoop ));
688 } else {
689 array->append(new_loc_value( _regalloc, regnum, _regalloc->is_oop(local) ? Location::oop : Location::normal ));
690 }
691 return;
692 }
693
694 // No register. It must be constant data.
695 switch (t->base()) {
696 case Type::Half: // Second half of a double
697 ShouldNotReachHere(); // Caller should skip 2nd halves
698 break;
699 case Type::AnyPtr:
700 array->append(new ConstantOopWriteValue(NULL));
701 break;
702 case Type::AryPtr:
703 case Type::InstPtr:
704 case Type::KlassPtr: // fall through
705 array->append(new ConstantOopWriteValue(t->isa_oopptr()->const_oop()->constant_encoding()));
706 break;
707 case Type::NarrowOop:
708 if (t == TypeNarrowOop::NULL_PTR) {
709 array->append(new ConstantOopWriteValue(NULL));
710 } else {
711 array->append(new ConstantOopWriteValue(t->make_ptr()->isa_oopptr()->const_oop()->constant_encoding()));
712 }
713 break;
714 case Type::Int:
715 array->append(new ConstantIntValue(t->is_int()->get_con()));
716 break;
717 case Type::RawPtr:
718 // A return address (T_ADDRESS).
719 assert((intptr_t)t->is_ptr()->get_con() < (intptr_t)0x10000, "must be a valid BCI");
720 #ifdef _LP64
721 // Must be restored to the full-width 64-bit stack slot.
722 array->append(new ConstantLongValue(t->is_ptr()->get_con()));
723 #else
724 array->append(new ConstantIntValue(t->is_ptr()->get_con()));
725 #endif
726 break;
727 case Type::FloatCon: {
728 float f = t->is_float_constant()->getf();
729 array->append(new ConstantIntValue(jint_cast(f)));
730 break;
731 }
732 case Type::DoubleCon: {
733 jdouble d = t->is_double_constant()->getd();
734 #ifdef _LP64
735 array->append(new ConstantIntValue(0));
736 array->append(new ConstantDoubleValue(d));
737 #else
738 // Repack the double as two jints.
739 // The convention the interpreter uses is that the second local
740 // holds the first raw word of the native double representation.
741 // This is actually reasonable, since locals and stack arrays
742 // grow downwards in all implementations.
743 // (If, on some machine, the interpreter's Java locals or stack
744 // were to grow upwards, the embedded doubles would be word-swapped.)
745 jint *dp = (jint*)&d;
746 array->append(new ConstantIntValue(dp[1]));
747 array->append(new ConstantIntValue(dp[0]));
748 #endif
749 break;
750 }
751 case Type::Long: {
752 jlong d = t->is_long()->get_con();
753 #ifdef _LP64
754 array->append(new ConstantIntValue(0));
755 array->append(new ConstantLongValue(d));
756 #else
757 // Repack the long as two jints.
758 // The convention the interpreter uses is that the second local
759 // holds the first raw word of the native double representation.
760 // This is actually reasonable, since locals and stack arrays
761 // grow downwards in all implementations.
762 // (If, on some machine, the interpreter's Java locals or stack
763 // were to grow upwards, the embedded doubles would be word-swapped.)
764 jint *dp = (jint*)&d;
765 array->append(new ConstantIntValue(dp[1]));
766 array->append(new ConstantIntValue(dp[0]));
767 #endif
768 break;
769 }
770 case Type::Top: // Add an illegal value here
771 array->append(new LocationValue(Location()));
772 break;
773 default:
774 ShouldNotReachHere();
775 break;
776 }
777 }
778
779 // Determine if this node starts a bundle
780 bool Compile::starts_bundle(const Node *n) const {
781 return (_node_bundling_limit > n->_idx &&
782 _node_bundling_base[n->_idx].starts_bundle());
783 }
784
785 //--------------------------Process_OopMap_Node--------------------------------
786 void Compile::Process_OopMap_Node(MachNode *mach, int current_offset) {
787
788 // Handle special safepoint nodes for synchronization
789 MachSafePointNode *sfn = mach->as_MachSafePoint();
790 MachCallNode *mcall;
791
792 #ifdef ENABLE_ZAP_DEAD_LOCALS
793 assert( is_node_getting_a_safepoint(mach), "logic does not match; false negative");
794 #endif
795
796 int safepoint_pc_offset = current_offset;
797
798 // Add the safepoint in the DebugInfoRecorder
799 if( !mach->is_MachCall() ) {
800 mcall = NULL;
801 debug_info()->add_safepoint(safepoint_pc_offset, sfn->_oop_map);
802 } else {
803 mcall = mach->as_MachCall();
804 safepoint_pc_offset += mcall->ret_addr_offset();
805 debug_info()->add_safepoint(safepoint_pc_offset, mcall->_oop_map);
806 }
807
808 // Loop over the JVMState list to add scope information
809 // Do not skip safepoints with a NULL method, they need monitor info
810 JVMState* youngest_jvms = sfn->jvms();
811 int max_depth = youngest_jvms->depth();
812
813 // Allocate the object pool for scalar-replaced objects -- the map from
814 // small-integer keys (which can be recorded in the local and ostack
815 // arrays) to descriptions of the object state.
816 GrowableArray<ScopeValue*> *objs = new GrowableArray<ScopeValue*>();
817
818 // Visit scopes from oldest to youngest.
819 for (int depth = 1; depth <= max_depth; depth++) {
820 JVMState* jvms = youngest_jvms->of_depth(depth);
821 int idx;
822 ciMethod* method = jvms->has_method() ? jvms->method() : NULL;
823 // Safepoints that do not have method() set only provide oop-map and monitor info
824 // to support GC; these do not support deoptimization.
825 int num_locs = (method == NULL) ? 0 : jvms->loc_size();
826 int num_exps = (method == NULL) ? 0 : jvms->stk_size();
827 int num_mon = jvms->nof_monitors();
828 assert(method == NULL || jvms->bci() < 0 || num_locs == method->max_locals(),
829 "JVMS local count must match that of the method");
830
831 // Add Local and Expression Stack Information
832
833 // Insert locals into the locarray
834 GrowableArray<ScopeValue*> *locarray = new GrowableArray<ScopeValue*>(num_locs);
835 for( idx = 0; idx < num_locs; idx++ ) {
836 FillLocArray( idx, sfn, sfn->local(jvms, idx), locarray, objs );
837 }
838
839 // Insert expression stack entries into the exparray
840 GrowableArray<ScopeValue*> *exparray = new GrowableArray<ScopeValue*>(num_exps);
841 for( idx = 0; idx < num_exps; idx++ ) {
842 FillLocArray( idx, sfn, sfn->stack(jvms, idx), exparray, objs );
843 }
844
845 // Add in mappings of the monitors
846 assert( !method ||
847 !method->is_synchronized() ||
848 method->is_native() ||
849 num_mon > 0 ||
850 !GenerateSynchronizationCode,
851 "monitors must always exist for synchronized methods");
852
853 // Build the growable array of ScopeValues for exp stack
854 GrowableArray<MonitorValue*> *monarray = new GrowableArray<MonitorValue*>(num_mon);
855
856 // Loop over monitors and insert into array
857 for(idx = 0; idx < num_mon; idx++) {
858 // Grab the node that defines this monitor
859 Node* box_node = sfn->monitor_box(jvms, idx);
860 Node* obj_node = sfn->monitor_obj(jvms, idx);
861
862 // Create ScopeValue for object
863 ScopeValue *scval = NULL;
864
865 if( obj_node->is_SafePointScalarObject() ) {
866 SafePointScalarObjectNode* spobj = obj_node->as_SafePointScalarObject();
867 scval = Compile::sv_for_node_id(objs, spobj->_idx);
868 if (scval == NULL) {
869 const Type *t = obj_node->bottom_type();
870 ciKlass* cik = t->is_oopptr()->klass();
871 assert(cik->is_instance_klass() ||
872 cik->is_array_klass(), "Not supported allocation.");
873 ObjectValue* sv = new ObjectValue(spobj->_idx,
874 new ConstantOopWriteValue(cik->constant_encoding()));
875 Compile::set_sv_for_object_node(objs, sv);
876
877 uint first_ind = spobj->first_index();
878 for (uint i = 0; i < spobj->n_fields(); i++) {
879 Node* fld_node = sfn->in(first_ind+i);
880 (void)FillLocArray(sv->field_values()->length(), sfn, fld_node, sv->field_values(), objs);
881 }
882 scval = sv;
883 }
884 } else if( !obj_node->is_Con() ) {
885 OptoReg::Name obj_reg = _regalloc->get_reg_first(obj_node);
886 if( obj_node->bottom_type()->base() == Type::NarrowOop ) {
887 scval = new_loc_value( _regalloc, obj_reg, Location::narrowoop );
888 } else {
889 scval = new_loc_value( _regalloc, obj_reg, Location::oop );
890 }
891 } else {
892 const TypePtr *tp = obj_node->bottom_type()->make_ptr();
893 scval = new ConstantOopWriteValue(tp->is_instptr()->const_oop()->constant_encoding());
894 }
895
896 OptoReg::Name box_reg = BoxLockNode::stack_slot(box_node);
897 Location basic_lock = Location::new_stk_loc(Location::normal,_regalloc->reg2offset(box_reg));
898 while( !box_node->is_BoxLock() ) box_node = box_node->in(1);
899 monarray->append(new MonitorValue(scval, basic_lock, box_node->as_BoxLock()->is_eliminated()));
900 }
901
902 // We dump the object pool first, since deoptimization reads it in first.
903 debug_info()->dump_object_pool(objs);
904
905 // Build first class objects to pass to scope
906 DebugToken *locvals = debug_info()->create_scope_values(locarray);
907 DebugToken *expvals = debug_info()->create_scope_values(exparray);
908 DebugToken *monvals = debug_info()->create_monitor_values(monarray);
909
910 // Make method available for all Safepoints
911 ciMethod* scope_method = method ? method : _method;
912 // Describe the scope here
913 assert(jvms->bci() >= InvocationEntryBci && jvms->bci() <= 0x10000, "must be a valid or entry BCI");
914 assert(!jvms->should_reexecute() || depth == max_depth, "reexecute allowed only for the youngest");
915 // Now we can describe the scope.
916 bool is_method_handle_invoke = false;
917 debug_info()->describe_scope(safepoint_pc_offset, scope_method, jvms->bci(), jvms->should_reexecute(), is_method_handle_invoke, locvals, expvals, monvals);
918 } // End jvms loop
919
920 // Mark the end of the scope set.
921 debug_info()->end_safepoint(safepoint_pc_offset);
922 }
923
924
925
926 // A simplified version of Process_OopMap_Node, to handle non-safepoints.
927 class NonSafepointEmitter {
928 Compile* C;
929 JVMState* _pending_jvms;
930 int _pending_offset;
931
932 void emit_non_safepoint();
933
934 public:
935 NonSafepointEmitter(Compile* compile) {
936 this->C = compile;
937 _pending_jvms = NULL;
938 _pending_offset = 0;
939 }
940
941 void observe_instruction(Node* n, int pc_offset) {
942 if (!C->debug_info()->recording_non_safepoints()) return;
943
944 Node_Notes* nn = C->node_notes_at(n->_idx);
945 if (nn == NULL || nn->jvms() == NULL) return;
946 if (_pending_jvms != NULL &&
947 _pending_jvms->same_calls_as(nn->jvms())) {
948 // Repeated JVMS? Stretch it up here.
949 _pending_offset = pc_offset;
950 } else {
951 if (_pending_jvms != NULL &&
952 _pending_offset < pc_offset) {
953 emit_non_safepoint();
954 }
955 _pending_jvms = NULL;
956 if (pc_offset > C->debug_info()->last_pc_offset()) {
957 // This is the only way _pending_jvms can become non-NULL:
958 _pending_jvms = nn->jvms();
959 _pending_offset = pc_offset;
960 }
961 }
962 }
963
964 // Stay out of the way of real safepoints:
965 void observe_safepoint(JVMState* jvms, int pc_offset) {
966 if (_pending_jvms != NULL &&
967 !_pending_jvms->same_calls_as(jvms) &&
968 _pending_offset < pc_offset) {
969 emit_non_safepoint();
970 }
971 _pending_jvms = NULL;
972 }
973
974 void flush_at_end() {
975 if (_pending_jvms != NULL) {
976 emit_non_safepoint();
977 }
978 _pending_jvms = NULL;
979 }
980 };
981
982 void NonSafepointEmitter::emit_non_safepoint() {
983 JVMState* youngest_jvms = _pending_jvms;
984 int pc_offset = _pending_offset;
985
986 // Clear it now:
987 _pending_jvms = NULL;
988
989 DebugInformationRecorder* debug_info = C->debug_info();
990 assert(debug_info->recording_non_safepoints(), "sanity");
991
992 debug_info->add_non_safepoint(pc_offset);
993 int max_depth = youngest_jvms->depth();
994
995 // Visit scopes from oldest to youngest.
996 for (int depth = 1; depth <= max_depth; depth++) {
997 JVMState* jvms = youngest_jvms->of_depth(depth);
998 ciMethod* method = jvms->has_method() ? jvms->method() : NULL;
999 assert(!jvms->should_reexecute() || depth==max_depth, "reexecute allowed only for the youngest");
1000 debug_info->describe_scope(pc_offset, method, jvms->bci(), jvms->should_reexecute());
1001 }
1002
1003 // Mark the end of the scope set.
1004 debug_info->end_non_safepoint(pc_offset);
1005 }
1006
1007
1008
1009 // helper for Fill_buffer bailout logic
1010 static void turn_off_compiler(Compile* C) {
1011 if (CodeCache::unallocated_capacity() >= CodeCacheMinimumFreeSpace*10) {
1012 // Do not turn off compilation if a single giant method has
1013 // blown the code cache size.
1014 C->record_failure("excessive request to CodeCache");
1015 } else {
1016 // Let CompilerBroker disable further compilations.
1017 C->record_failure("CodeCache is full");
1018 }
1019 }
1020
1021
1022 //------------------------------Fill_buffer------------------------------------
1023 void Compile::Fill_buffer() {
1024
1025 // Set the initially allocated size
1026 int code_req = initial_code_capacity;
1027 int locs_req = initial_locs_capacity;
1028 int stub_req = TraceJumps ? initial_stub_capacity * 10 : initial_stub_capacity;
1029 int const_req = initial_const_capacity;
1030 bool labels_not_set = true;
1031
1032 int pad_req = NativeCall::instruction_size;
1033 // The extra spacing after the code is necessary on some platforms.
1034 // Sometimes we need to patch in a jump after the last instruction,
1035 // if the nmethod has been deoptimized. (See 4932387, 4894843.)
1036
1037 uint i;
1038 // Compute the byte offset where we can store the deopt pc.
1039 if (fixed_slots() != 0) {
1040 _orig_pc_slot_offset_in_bytes = _regalloc->reg2offset(OptoReg::stack2reg(_orig_pc_slot));
1041 }
1042
1043 // Compute prolog code size
1044 _method_size = 0;
1045 _frame_slots = OptoReg::reg2stack(_matcher->_old_SP)+_regalloc->_framesize;
1046 #ifdef IA64
1047 if (save_argument_registers()) {
1048 // 4815101: this is a stub with implicit and unknown precision fp args.
1049 // The usual spill mechanism can only generate stfd's in this case, which
1050 // doesn't work if the fp reg to spill contains a single-precision denorm.
1051 // Instead, we hack around the normal spill mechanism using stfspill's and
1052 // ldffill's in the MachProlog and MachEpilog emit methods. We allocate
1053 // space here for the fp arg regs (f8-f15) we're going to thusly spill.
1054 //
1055 // If we ever implement 16-byte 'registers' == stack slots, we can
1056 // get rid of this hack and have SpillCopy generate stfspill/ldffill
1057 // instead of stfd/stfs/ldfd/ldfs.
1058 _frame_slots += 8*(16/BytesPerInt);
1059 }
1060 #endif
1061 assert( _frame_slots >= 0 && _frame_slots < 1000000, "sanity check" );
1062
1063 // Create an array of unused labels, one for each basic block
1064 Label *blk_labels = NEW_RESOURCE_ARRAY(Label, _cfg->_num_blocks+1);
1065
1066 for( i=0; i <= _cfg->_num_blocks; i++ ) {
1067 blk_labels[i].init();
1068 }
1069
1070 // If this machine supports different size branch offsets, then pre-compute
1071 // the length of the blocks
1072 if( _matcher->is_short_branch_offset(-1, 0) ) {
1073 Shorten_branches(blk_labels, code_req, locs_req, stub_req, const_req);
1074 labels_not_set = false;
1075 }
1076
1077 // nmethod and CodeBuffer count stubs & constants as part of method's code.
1078 int exception_handler_req = size_exception_handler();
1079 int deopt_handler_req = size_deopt_handler();
1080 exception_handler_req += MAX_stubs_size; // add marginal slop for handler
1081 deopt_handler_req += MAX_stubs_size; // add marginal slop for handler
1082 stub_req += MAX_stubs_size; // ensure per-stub margin
1083 code_req += MAX_inst_size; // ensure per-instruction margin
1084 if (StressCodeBuffers)
1085 code_req = const_req = stub_req = exception_handler_req = deopt_handler_req = 0x10; // force expansion
1086 int total_req = code_req + pad_req + stub_req + exception_handler_req + deopt_handler_req + const_req;
1087 CodeBuffer* cb = code_buffer();
1088 cb->initialize(total_req, locs_req);
1089
1090 // Have we run out of code space?
1091 if (cb->blob() == NULL) {
1092 turn_off_compiler(this);
1093 return;
1094 }
1095 // Configure the code buffer.
1096 cb->initialize_consts_size(const_req);
1097 cb->initialize_stubs_size(stub_req);
1098 cb->initialize_oop_recorder(env()->oop_recorder());
1099
1100 // fill in the nop array for bundling computations
1101 MachNode *_nop_list[Bundle::_nop_count];
1102 Bundle::initialize_nops(_nop_list, this);
1103
1104 // Create oopmap set.
1105 _oop_map_set = new OopMapSet();
1106
1107 // !!!!! This preserves old handling of oopmaps for now
1108 debug_info()->set_oopmaps(_oop_map_set);
1109
1110 // Count and start of implicit null check instructions
1111 uint inct_cnt = 0;
1112 uint *inct_starts = NEW_RESOURCE_ARRAY(uint, _cfg->_num_blocks+1);
1113
1114 // Count and start of calls
1115 uint *call_returns = NEW_RESOURCE_ARRAY(uint, _cfg->_num_blocks+1);
1116
1117 uint return_offset = 0;
1118 int nop_size = (new (this) MachNopNode())->size(_regalloc);
1119
1120 int previous_offset = 0;
1121 int current_offset = 0;
1122 int last_call_offset = -1;
1123
1124 // Create an array of unused labels, one for each basic block, if printing is enabled
1125 #ifndef PRODUCT
1126 int *node_offsets = NULL;
1127 uint node_offset_limit = unique();
1128
1129
1130 if ( print_assembly() )
1131 node_offsets = NEW_RESOURCE_ARRAY(int, node_offset_limit);
1132 #endif
1133
1134 NonSafepointEmitter non_safepoints(this); // emit non-safepoints lazily
1135
1136 // ------------------
1137 // Now fill in the code buffer
1138 Node *delay_slot = NULL;
1139
1140 for( i=0; i < _cfg->_num_blocks; i++ ) {
1141 Block *b = _cfg->_blocks[i];
1142
1143 Node *head = b->head();
1144
1145 // If this block needs to start aligned (i.e, can be reached other
1146 // than by falling-thru from the previous block), then force the
1147 // start of a new bundle.
1148 if( Pipeline::requires_bundling() && starts_bundle(head) )
1149 cb->flush_bundle(true);
1150
1151 // Define the label at the beginning of the basic block
1152 if( labels_not_set )
1153 MacroAssembler(cb).bind( blk_labels[b->_pre_order] );
1154
1155 else
1156 assert( blk_labels[b->_pre_order].loc_pos() == cb->code_size(),
1157 "label position does not match code offset" );
1158
1159 uint last_inst = b->_nodes.size();
1160
1161 // Emit block normally, except for last instruction.
1162 // Emit means "dump code bits into code buffer".
1163 for( uint j = 0; j<last_inst; j++ ) {
1164
1165 // Get the node
1166 Node* n = b->_nodes[j];
1167
1168 // See if delay slots are supported
1169 if (valid_bundle_info(n) &&
1170 node_bundling(n)->used_in_unconditional_delay()) {
1171 assert(delay_slot == NULL, "no use of delay slot node");
1172 assert(n->size(_regalloc) == Pipeline::instr_unit_size(), "delay slot instruction wrong size");
1173
1174 delay_slot = n;
1175 continue;
1176 }
1177
1178 // If this starts a new instruction group, then flush the current one
1179 // (but allow split bundles)
1180 if( Pipeline::requires_bundling() && starts_bundle(n) )
1181 cb->flush_bundle(false);
1182
1183 // The following logic is duplicated in the code ifdeffed for
1184 // ENABLE_ZAP_DEAD_LOCALS which appears above in this file. It
1185 // should be factored out. Or maybe dispersed to the nodes?
1186
1187 // Special handling for SafePoint/Call Nodes
1188 bool is_mcall = false;
1189 if( n->is_Mach() ) {
1190 MachNode *mach = n->as_Mach();
1191 is_mcall = n->is_MachCall();
1192 bool is_sfn = n->is_MachSafePoint();
1193
1194 // If this requires all previous instructions be flushed, then do so
1195 if( is_sfn || is_mcall || mach->alignment_required() != 1) {
1196 cb->flush_bundle(true);
1197 current_offset = cb->code_size();
1198 }
1199
1200 // align the instruction if necessary
1201 int padding = mach->compute_padding(current_offset);
1202 // Make sure safepoint node for polling is distinct from a call's
1203 // return by adding a nop if needed.
1204 if (is_sfn && !is_mcall && padding == 0 && current_offset == last_call_offset ) {
1205 padding = nop_size;
1206 }
1207 assert( labels_not_set || padding == 0, "instruction should already be aligned")
1208
1209 if(padding > 0) {
1210 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size");
1211 int nops_cnt = padding / nop_size;
1212 MachNode *nop = new (this) MachNopNode(nops_cnt);
1213 b->_nodes.insert(j++, nop);
1214 last_inst++;
1215 _cfg->_bbs.map( nop->_idx, b );
1216 nop->emit(*cb, _regalloc);
1217 cb->flush_bundle(true);
1218 current_offset = cb->code_size();
1219 }
1220
1221 // Remember the start of the last call in a basic block
1222 if (is_mcall) {
1223 MachCallNode *mcall = mach->as_MachCall();
1224
1225 // This destination address is NOT PC-relative
1226 mcall->method_set((intptr_t)mcall->entry_point());
1227
1228 // Save the return address
1229 call_returns[b->_pre_order] = current_offset + mcall->ret_addr_offset();
1230
1231 if (!mcall->is_safepoint_node()) {
1232 is_mcall = false;
1233 is_sfn = false;
1234 }
1235 }
1236
1237 // sfn will be valid whenever mcall is valid now because of inheritance
1238 if( is_sfn || is_mcall ) {
1239
1240 // Handle special safepoint nodes for synchronization
1241 if( !is_mcall ) {
1242 MachSafePointNode *sfn = mach->as_MachSafePoint();
1243 // !!!!! Stubs only need an oopmap right now, so bail out
1244 if( sfn->jvms()->method() == NULL) {
1245 // Write the oopmap directly to the code blob??!!
1246 # ifdef ENABLE_ZAP_DEAD_LOCALS
1247 assert( !is_node_getting_a_safepoint(sfn), "logic does not match; false positive");
1248 # endif
1249 continue;
1250 }
1251 } // End synchronization
1252
1253 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(),
1254 current_offset);
1255 Process_OopMap_Node(mach, current_offset);
1256 } // End if safepoint
1257
1258 // If this is a null check, then add the start of the previous instruction to the list
1259 else if( mach->is_MachNullCheck() ) {
1260 inct_starts[inct_cnt++] = previous_offset;
1261 }
1262
1263 // If this is a branch, then fill in the label with the target BB's label
1264 else if ( mach->is_Branch() ) {
1265
1266 if ( mach->ideal_Opcode() == Op_Jump ) {
1267 for (uint h = 0; h < b->_num_succs; h++ ) {
1268 Block* succs_block = b->_succs[h];
1269 for (uint j = 1; j < succs_block->num_preds(); j++) {
1270 Node* jpn = succs_block->pred(j);
1271 if ( jpn->is_JumpProj() && jpn->in(0) == mach ) {
1272 uint block_num = succs_block->non_connector()->_pre_order;
1273 Label *blkLabel = &blk_labels[block_num];
1274 mach->add_case_label(jpn->as_JumpProj()->proj_no(), blkLabel);
1275 }
1276 }
1277 }
1278 } else {
1279 // For Branchs
1280 // This requires the TRUE branch target be in succs[0]
1281 uint block_num = b->non_connector_successor(0)->_pre_order;
1282 mach->label_set( blk_labels[block_num], block_num );
1283 }
1284 }
1285
1286 #ifdef ASSERT
1287 // Check that oop-store precedes the card-mark
1288 else if( mach->ideal_Opcode() == Op_StoreCM ) {
1289 uint storeCM_idx = j;
1290 Node *oop_store = mach->in(mach->_cnt); // First precedence edge
1291 assert( oop_store != NULL, "storeCM expects a precedence edge");
1292 uint i4;
1293 for( i4 = 0; i4 < last_inst; ++i4 ) {
1294 if( b->_nodes[i4] == oop_store ) break;
1295 }
1296 // Note: This test can provide a false failure if other precedence
1297 // edges have been added to the storeCMNode.
1298 assert( i4 == last_inst || i4 < storeCM_idx, "CM card-mark executes before oop-store");
1299 }
1300 #endif
1301
1302 else if( !n->is_Proj() ) {
1303 // Remember the beginning of the previous instruction, in case
1304 // it's followed by a flag-kill and a null-check. Happens on
1305 // Intel all the time, with add-to-memory kind of opcodes.
1306 previous_offset = current_offset;
1307 }
1308 }
1309
1310 // Verify that there is sufficient space remaining
1311 cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size);
1312 if (cb->blob() == NULL) {
1313 turn_off_compiler(this);
1314 return;
1315 }
1316
1317 // Save the offset for the listing
1318 #ifndef PRODUCT
1319 if( node_offsets && n->_idx < node_offset_limit )
1320 node_offsets[n->_idx] = cb->code_size();
1321 #endif
1322
1323 // "Normal" instruction case
1324 n->emit(*cb, _regalloc);
1325 current_offset = cb->code_size();
1326 non_safepoints.observe_instruction(n, current_offset);
1327
1328 // mcall is last "call" that can be a safepoint
1329 // record it so we can see if a poll will directly follow it
1330 // in which case we'll need a pad to make the PcDesc sites unique
1331 // see 5010568. This can be slightly inaccurate but conservative
1332 // in the case that return address is not actually at current_offset.
1333 // This is a small price to pay.
1334
1335 if (is_mcall) {
1336 last_call_offset = current_offset;
1337 }
1338
1339 // See if this instruction has a delay slot
1340 if ( valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
1341 assert(delay_slot != NULL, "expecting delay slot node");
1342
1343 // Back up 1 instruction
1344 cb->set_code_end(
1345 cb->code_end()-Pipeline::instr_unit_size());
1346
1347 // Save the offset for the listing
1348 #ifndef PRODUCT
1349 if( node_offsets && delay_slot->_idx < node_offset_limit )
1350 node_offsets[delay_slot->_idx] = cb->code_size();
1351 #endif
1352
1353 // Support a SafePoint in the delay slot
1354 if( delay_slot->is_MachSafePoint() ) {
1355 MachNode *mach = delay_slot->as_Mach();
1356 // !!!!! Stubs only need an oopmap right now, so bail out
1357 if( !mach->is_MachCall() && mach->as_MachSafePoint()->jvms()->method() == NULL ) {
1358 // Write the oopmap directly to the code blob??!!
1359 # ifdef ENABLE_ZAP_DEAD_LOCALS
1360 assert( !is_node_getting_a_safepoint(mach), "logic does not match; false positive");
1361 # endif
1362 delay_slot = NULL;
1363 continue;
1364 }
1365
1366 int adjusted_offset = current_offset - Pipeline::instr_unit_size();
1367 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(),
1368 adjusted_offset);
1369 // Generate an OopMap entry
1370 Process_OopMap_Node(mach, adjusted_offset);
1371 }
1372
1373 // Insert the delay slot instruction
1374 delay_slot->emit(*cb, _regalloc);
1375
1376 // Don't reuse it
1377 delay_slot = NULL;
1378 }
1379
1380 } // End for all instructions in block
1381
1382 // If the next block is the top of a loop, pad this block out to align
1383 // the loop top a little. Helps prevent pipe stalls at loop back branches.
1384 if( i<_cfg->_num_blocks-1 ) {
1385 Block *nb = _cfg->_blocks[i+1];
1386 uint padding = nb->alignment_padding(current_offset);
1387 if( padding > 0 ) {
1388 MachNode *nop = new (this) MachNopNode(padding / nop_size);
1389 b->_nodes.insert( b->_nodes.size(), nop );
1390 _cfg->_bbs.map( nop->_idx, b );
1391 nop->emit(*cb, _regalloc);
1392 current_offset = cb->code_size();
1393 }
1394 }
1395
1396 } // End of for all blocks
1397
1398 non_safepoints.flush_at_end();
1399
1400 // Offset too large?
1401 if (failing()) return;
1402
1403 // Define a pseudo-label at the end of the code
1404 MacroAssembler(cb).bind( blk_labels[_cfg->_num_blocks] );
1405
1406 // Compute the size of the first block
1407 _first_block_size = blk_labels[1].loc_pos() - blk_labels[0].loc_pos();
1408
1409 assert(cb->code_size() < 500000, "method is unreasonably large");
1410
1411 // ------------------
1412
1413 #ifndef PRODUCT
1414 // Information on the size of the method, without the extraneous code
1415 Scheduling::increment_method_size(cb->code_size());
1416 #endif
1417
1418 // ------------------
1419 // Fill in exception table entries.
1420 FillExceptionTables(inct_cnt, call_returns, inct_starts, blk_labels);
1421
1422 // Only java methods have exception handlers and deopt handlers
1423 if (_method) {
1424 // Emit the exception handler code.
1425 _code_offsets.set_value(CodeOffsets::Exceptions, emit_exception_handler(*cb));
1426 // Emit the deopt handler code.
1427 _code_offsets.set_value(CodeOffsets::Deopt, emit_deopt_handler(*cb));
1428 }
1429
1430 // One last check for failed CodeBuffer::expand:
1431 if (cb->blob() == NULL) {
1432 turn_off_compiler(this);
1433 return;
1434 }
1435
1436 #ifndef PRODUCT
1437 // Dump the assembly code, including basic-block numbers
1438 if (print_assembly()) {
1439 ttyLocker ttyl; // keep the following output all in one block
1440 if (!VMThread::should_terminate()) { // test this under the tty lock
1441 // This output goes directly to the tty, not the compiler log.
1442 // To enable tools to match it up with the compilation activity,
1443 // be sure to tag this tty output with the compile ID.
1444 if (xtty != NULL) {
1445 xtty->head("opto_assembly compile_id='%d'%s", compile_id(),
1446 is_osr_compilation() ? " compile_kind='osr'" :
1447 "");
1448 }
1449 if (method() != NULL) {
1450 method()->print_oop();
1451 print_codes();
1452 }
1453 dump_asm(node_offsets, node_offset_limit);
1454 if (xtty != NULL) {
1455 xtty->tail("opto_assembly");
1456 }
1457 }
1458 }
1459 #endif
1460
1461 }
1462
1463 void Compile::FillExceptionTables(uint cnt, uint *call_returns, uint *inct_starts, Label *blk_labels) {
1464 _inc_table.set_size(cnt);
1465
1466 uint inct_cnt = 0;
1467 for( uint i=0; i<_cfg->_num_blocks; i++ ) {
1468 Block *b = _cfg->_blocks[i];
1469 Node *n = NULL;
1470 int j;
1471
1472 // Find the branch; ignore trailing NOPs.
1473 for( j = b->_nodes.size()-1; j>=0; j-- ) {
1474 n = b->_nodes[j];
1475 if( !n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con )
1476 break;
1477 }
1478
1479 // If we didn't find anything, continue
1480 if( j < 0 ) continue;
1481
1482 // Compute ExceptionHandlerTable subtable entry and add it
1483 // (skip empty blocks)
1484 if( n->is_Catch() ) {
1485
1486 // Get the offset of the return from the call
1487 uint call_return = call_returns[b->_pre_order];
1488 #ifdef ASSERT
1489 assert( call_return > 0, "no call seen for this basic block" );
1490 while( b->_nodes[--j]->Opcode() == Op_MachProj ) ;
1491 assert( b->_nodes[j]->is_Call(), "CatchProj must follow call" );
1492 #endif
1493 // last instruction is a CatchNode, find it's CatchProjNodes
1494 int nof_succs = b->_num_succs;
1495 // allocate space
1496 GrowableArray<intptr_t> handler_bcis(nof_succs);
1497 GrowableArray<intptr_t> handler_pcos(nof_succs);
1498 // iterate through all successors
1499 for (int j = 0; j < nof_succs; j++) {
1500 Block* s = b->_succs[j];
1501 bool found_p = false;
1502 for( uint k = 1; k < s->num_preds(); k++ ) {
1503 Node *pk = s->pred(k);
1504 if( pk->is_CatchProj() && pk->in(0) == n ) {
1505 const CatchProjNode* p = pk->as_CatchProj();
1506 found_p = true;
1507 // add the corresponding handler bci & pco information
1508 if( p->_con != CatchProjNode::fall_through_index ) {
1509 // p leads to an exception handler (and is not fall through)
1510 assert(s == _cfg->_blocks[s->_pre_order],"bad numbering");
1511 // no duplicates, please
1512 if( !handler_bcis.contains(p->handler_bci()) ) {
1513 uint block_num = s->non_connector()->_pre_order;
1514 handler_bcis.append(p->handler_bci());
1515 handler_pcos.append(blk_labels[block_num].loc_pos());
1516 }
1517 }
1518 }
1519 }
1520 assert(found_p, "no matching predecessor found");
1521 // Note: Due to empty block removal, one block may have
1522 // several CatchProj inputs, from the same Catch.
1523 }
1524
1525 // Set the offset of the return from the call
1526 _handler_table.add_subtable(call_return, &handler_bcis, NULL, &handler_pcos);
1527 continue;
1528 }
1529
1530 // Handle implicit null exception table updates
1531 if( n->is_MachNullCheck() ) {
1532 uint block_num = b->non_connector_successor(0)->_pre_order;
1533 _inc_table.append( inct_starts[inct_cnt++], blk_labels[block_num].loc_pos() );
1534 continue;
1535 }
1536 } // End of for all blocks fill in exception table entries
1537 }
1538
1539 // Static Variables
1540 #ifndef PRODUCT
1541 uint Scheduling::_total_nop_size = 0;
1542 uint Scheduling::_total_method_size = 0;
1543 uint Scheduling::_total_branches = 0;
1544 uint Scheduling::_total_unconditional_delays = 0;
1545 uint Scheduling::_total_instructions_per_bundle[Pipeline::_max_instrs_per_cycle+1];
1546 #endif
1547
1548 // Initializer for class Scheduling
1549
1550 Scheduling::Scheduling(Arena *arena, Compile &compile)
1551 : _arena(arena),
1552 _cfg(compile.cfg()),
1553 _bbs(compile.cfg()->_bbs),
1554 _regalloc(compile.regalloc()),
1555 _reg_node(arena),
1556 _bundle_instr_count(0),
1557 _bundle_cycle_number(0),
1558 _scheduled(arena),
1559 _available(arena),
1560 _next_node(NULL),
1561 _bundle_use(0, 0, resource_count, &_bundle_use_elements[0]),
1562 _pinch_free_list(arena)
1563 #ifndef PRODUCT
1564 , _branches(0)
1565 , _unconditional_delays(0)
1566 #endif
1567 {
1568 // Create a MachNopNode
1569 _nop = new (&compile) MachNopNode();
1570
1571 // Now that the nops are in the array, save the count
1572 // (but allow entries for the nops)
1573 _node_bundling_limit = compile.unique();
1574 uint node_max = _regalloc->node_regs_max_index();
1575
1576 compile.set_node_bundling_limit(_node_bundling_limit);
1577
1578 // This one is persistent within the Compile class
1579 _node_bundling_base = NEW_ARENA_ARRAY(compile.comp_arena(), Bundle, node_max);
1580
1581 // Allocate space for fixed-size arrays
1582 _node_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max);
1583 _uses = NEW_ARENA_ARRAY(arena, short, node_max);
1584 _current_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max);
1585
1586 // Clear the arrays
1587 memset(_node_bundling_base, 0, node_max * sizeof(Bundle));
1588 memset(_node_latency, 0, node_max * sizeof(unsigned short));
1589 memset(_uses, 0, node_max * sizeof(short));
1590 memset(_current_latency, 0, node_max * sizeof(unsigned short));
1591
1592 // Clear the bundling information
1593 memcpy(_bundle_use_elements,
1594 Pipeline_Use::elaborated_elements,
1595 sizeof(Pipeline_Use::elaborated_elements));
1596
1597 // Get the last node
1598 Block *bb = _cfg->_blocks[_cfg->_blocks.size()-1];
1599
1600 _next_node = bb->_nodes[bb->_nodes.size()-1];
1601 }
1602
1603 #ifndef PRODUCT
1604 // Scheduling destructor
1605 Scheduling::~Scheduling() {
1606 _total_branches += _branches;
1607 _total_unconditional_delays += _unconditional_delays;
1608 }
1609 #endif
1610
1611 // Step ahead "i" cycles
1612 void Scheduling::step(uint i) {
1613
1614 Bundle *bundle = node_bundling(_next_node);
1615 bundle->set_starts_bundle();
1616
1617 // Update the bundle record, but leave the flags information alone
1618 if (_bundle_instr_count > 0) {
1619 bundle->set_instr_count(_bundle_instr_count);
1620 bundle->set_resources_used(_bundle_use.resourcesUsed());
1621 }
1622
1623 // Update the state information
1624 _bundle_instr_count = 0;
1625 _bundle_cycle_number += i;
1626 _bundle_use.step(i);
1627 }
1628
1629 void Scheduling::step_and_clear() {
1630 Bundle *bundle = node_bundling(_next_node);
1631 bundle->set_starts_bundle();
1632
1633 // Update the bundle record
1634 if (_bundle_instr_count > 0) {
1635 bundle->set_instr_count(_bundle_instr_count);
1636 bundle->set_resources_used(_bundle_use.resourcesUsed());
1637
1638 _bundle_cycle_number += 1;
1639 }
1640
1641 // Clear the bundling information
1642 _bundle_instr_count = 0;
1643 _bundle_use.reset();
1644
1645 memcpy(_bundle_use_elements,
1646 Pipeline_Use::elaborated_elements,
1647 sizeof(Pipeline_Use::elaborated_elements));
1648 }
1649
1650 //------------------------------ScheduleAndBundle------------------------------
1651 // Perform instruction scheduling and bundling over the sequence of
1652 // instructions in backwards order.
1653 void Compile::ScheduleAndBundle() {
1654
1655 // Don't optimize this if it isn't a method
1656 if (!_method)
1657 return;
1658
1659 // Don't optimize this if scheduling is disabled
1660 if (!do_scheduling())
1661 return;
1662
1663 NOT_PRODUCT( TracePhase t2("isched", &_t_instrSched, TimeCompiler); )
1664
1665 // Create a data structure for all the scheduling information
1666 Scheduling scheduling(Thread::current()->resource_area(), *this);
1667
1668 // Walk backwards over each basic block, computing the needed alignment
1669 // Walk over all the basic blocks
1670 scheduling.DoScheduling();
1671 }
1672
1673 //------------------------------ComputeLocalLatenciesForward-------------------
1674 // Compute the latency of all the instructions. This is fairly simple,
1675 // because we already have a legal ordering. Walk over the instructions
1676 // from first to last, and compute the latency of the instruction based
1677 // on the latency of the preceding instruction(s).
1678 void Scheduling::ComputeLocalLatenciesForward(const Block *bb) {
1679 #ifndef PRODUCT
1680 if (_cfg->C->trace_opto_output())
1681 tty->print("# -> ComputeLocalLatenciesForward\n");
1682 #endif
1683
1684 // Walk over all the schedulable instructions
1685 for( uint j=_bb_start; j < _bb_end; j++ ) {
1686
1687 // This is a kludge, forcing all latency calculations to start at 1.
1688 // Used to allow latency 0 to force an instruction to the beginning
1689 // of the bb
1690 uint latency = 1;
1691 Node *use = bb->_nodes[j];
1692 uint nlen = use->len();
1693
1694 // Walk over all the inputs
1695 for ( uint k=0; k < nlen; k++ ) {
1696 Node *def = use->in(k);
1697 if (!def)
1698 continue;
1699
1700 uint l = _node_latency[def->_idx] + use->latency(k);
1701 if (latency < l)
1702 latency = l;
1703 }
1704
1705 _node_latency[use->_idx] = latency;
1706
1707 #ifndef PRODUCT
1708 if (_cfg->C->trace_opto_output()) {
1709 tty->print("# latency %4d: ", latency);
1710 use->dump();
1711 }
1712 #endif
1713 }
1714
1715 #ifndef PRODUCT
1716 if (_cfg->C->trace_opto_output())
1717 tty->print("# <- ComputeLocalLatenciesForward\n");
1718 #endif
1719
1720 } // end ComputeLocalLatenciesForward
1721
1722 // See if this node fits into the present instruction bundle
1723 bool Scheduling::NodeFitsInBundle(Node *n) {
1724 uint n_idx = n->_idx;
1725
1726 // If this is the unconditional delay instruction, then it fits
1727 if (n == _unconditional_delay_slot) {
1728 #ifndef PRODUCT
1729 if (_cfg->C->trace_opto_output())
1730 tty->print("# NodeFitsInBundle [%4d]: TRUE; is in unconditional delay slot\n", n->_idx);
1731 #endif
1732 return (true);
1733 }
1734
1735 // If the node cannot be scheduled this cycle, skip it
1736 if (_current_latency[n_idx] > _bundle_cycle_number) {
1737 #ifndef PRODUCT
1738 if (_cfg->C->trace_opto_output())
1739 tty->print("# NodeFitsInBundle [%4d]: FALSE; latency %4d > %d\n",
1740 n->_idx, _current_latency[n_idx], _bundle_cycle_number);
1741 #endif
1742 return (false);
1743 }
1744
1745 const Pipeline *node_pipeline = n->pipeline();
1746
1747 uint instruction_count = node_pipeline->instructionCount();
1748 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0)
1749 instruction_count = 0;
1750 else if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot)
1751 instruction_count++;
1752
1753 if (_bundle_instr_count + instruction_count > Pipeline::_max_instrs_per_cycle) {
1754 #ifndef PRODUCT
1755 if (_cfg->C->trace_opto_output())
1756 tty->print("# NodeFitsInBundle [%4d]: FALSE; too many instructions: %d > %d\n",
1757 n->_idx, _bundle_instr_count + instruction_count, Pipeline::_max_instrs_per_cycle);
1758 #endif
1759 return (false);
1760 }
1761
1762 // Don't allow non-machine nodes to be handled this way
1763 if (!n->is_Mach() && instruction_count == 0)
1764 return (false);
1765
1766 // See if there is any overlap
1767 uint delay = _bundle_use.full_latency(0, node_pipeline->resourceUse());
1768
1769 if (delay > 0) {
1770 #ifndef PRODUCT
1771 if (_cfg->C->trace_opto_output())
1772 tty->print("# NodeFitsInBundle [%4d]: FALSE; functional units overlap\n", n_idx);
1773 #endif
1774 return false;
1775 }
1776
1777 #ifndef PRODUCT
1778 if (_cfg->C->trace_opto_output())
1779 tty->print("# NodeFitsInBundle [%4d]: TRUE\n", n_idx);
1780 #endif
1781
1782 return true;
1783 }
1784
1785 Node * Scheduling::ChooseNodeToBundle() {
1786 uint siz = _available.size();
1787
1788 if (siz == 0) {
1789
1790 #ifndef PRODUCT
1791 if (_cfg->C->trace_opto_output())
1792 tty->print("# ChooseNodeToBundle: NULL\n");
1793 #endif
1794 return (NULL);
1795 }
1796
1797 // Fast path, if only 1 instruction in the bundle
1798 if (siz == 1) {
1799 #ifndef PRODUCT
1800 if (_cfg->C->trace_opto_output()) {
1801 tty->print("# ChooseNodeToBundle (only 1): ");
1802 _available[0]->dump();
1803 }
1804 #endif
1805 return (_available[0]);
1806 }
1807
1808 // Don't bother, if the bundle is already full
1809 if (_bundle_instr_count < Pipeline::_max_instrs_per_cycle) {
1810 for ( uint i = 0; i < siz; i++ ) {
1811 Node *n = _available[i];
1812
1813 // Skip projections, we'll handle them another way
1814 if (n->is_Proj())
1815 continue;
1816
1817 // This presupposed that instructions are inserted into the
1818 // available list in a legality order; i.e. instructions that
1819 // must be inserted first are at the head of the list
1820 if (NodeFitsInBundle(n)) {
1821 #ifndef PRODUCT
1822 if (_cfg->C->trace_opto_output()) {
1823 tty->print("# ChooseNodeToBundle: ");
1824 n->dump();
1825 }
1826 #endif
1827 return (n);
1828 }
1829 }
1830 }
1831
1832 // Nothing fits in this bundle, choose the highest priority
1833 #ifndef PRODUCT
1834 if (_cfg->C->trace_opto_output()) {
1835 tty->print("# ChooseNodeToBundle: ");
1836 _available[0]->dump();
1837 }
1838 #endif
1839
1840 return _available[0];
1841 }
1842
1843 //------------------------------AddNodeToAvailableList-------------------------
1844 void Scheduling::AddNodeToAvailableList(Node *n) {
1845 assert( !n->is_Proj(), "projections never directly made available" );
1846 #ifndef PRODUCT
1847 if (_cfg->C->trace_opto_output()) {
1848 tty->print("# AddNodeToAvailableList: ");
1849 n->dump();
1850 }
1851 #endif
1852
1853 int latency = _current_latency[n->_idx];
1854
1855 // Insert in latency order (insertion sort)
1856 uint i;
1857 for ( i=0; i < _available.size(); i++ )
1858 if (_current_latency[_available[i]->_idx] > latency)
1859 break;
1860
1861 // Special Check for compares following branches
1862 if( n->is_Mach() && _scheduled.size() > 0 ) {
1863 int op = n->as_Mach()->ideal_Opcode();
1864 Node *last = _scheduled[0];
1865 if( last->is_MachIf() && last->in(1) == n &&
1866 ( op == Op_CmpI ||
1867 op == Op_CmpU ||
1868 op == Op_CmpP ||
1869 op == Op_CmpF ||
1870 op == Op_CmpD ||
1871 op == Op_CmpL ) ) {
1872
1873 // Recalculate position, moving to front of same latency
1874 for ( i=0 ; i < _available.size(); i++ )
1875 if (_current_latency[_available[i]->_idx] >= latency)
1876 break;
1877 }
1878 }
1879
1880 // Insert the node in the available list
1881 _available.insert(i, n);
1882
1883 #ifndef PRODUCT
1884 if (_cfg->C->trace_opto_output())
1885 dump_available();
1886 #endif
1887 }
1888
1889 //------------------------------DecrementUseCounts-----------------------------
1890 void Scheduling::DecrementUseCounts(Node *n, const Block *bb) {
1891 for ( uint i=0; i < n->len(); i++ ) {
1892 Node *def = n->in(i);
1893 if (!def) continue;
1894 if( def->is_Proj() ) // If this is a machine projection, then
1895 def = def->in(0); // propagate usage thru to the base instruction
1896
1897 if( _bbs[def->_idx] != bb ) // Ignore if not block-local
1898 continue;
1899
1900 // Compute the latency
1901 uint l = _bundle_cycle_number + n->latency(i);
1902 if (_current_latency[def->_idx] < l)
1903 _current_latency[def->_idx] = l;
1904
1905 // If this does not have uses then schedule it
1906 if ((--_uses[def->_idx]) == 0)
1907 AddNodeToAvailableList(def);
1908 }
1909 }
1910
1911 //------------------------------AddNodeToBundle--------------------------------
1912 void Scheduling::AddNodeToBundle(Node *n, const Block *bb) {
1913 #ifndef PRODUCT
1914 if (_cfg->C->trace_opto_output()) {
1915 tty->print("# AddNodeToBundle: ");
1916 n->dump();
1917 }
1918 #endif
1919
1920 // Remove this from the available list
1921 uint i;
1922 for (i = 0; i < _available.size(); i++)
1923 if (_available[i] == n)
1924 break;
1925 assert(i < _available.size(), "entry in _available list not found");
1926 _available.remove(i);
1927
1928 // See if this fits in the current bundle
1929 const Pipeline *node_pipeline = n->pipeline();
1930 const Pipeline_Use& node_usage = node_pipeline->resourceUse();
1931
1932 // Check for instructions to be placed in the delay slot. We
1933 // do this before we actually schedule the current instruction,
1934 // because the delay slot follows the current instruction.
1935 if (Pipeline::_branch_has_delay_slot &&
1936 node_pipeline->hasBranchDelay() &&
1937 !_unconditional_delay_slot) {
1938
1939 uint siz = _available.size();
1940
1941 // Conditional branches can support an instruction that
1942 // is unconditionally executed and not dependent by the
1943 // branch, OR a conditionally executed instruction if
1944 // the branch is taken. In practice, this means that
1945 // the first instruction at the branch target is
1946 // copied to the delay slot, and the branch goes to
1947 // the instruction after that at the branch target
1948 if ( n->is_Mach() && n->is_Branch() ) {
1949
1950 assert( !n->is_MachNullCheck(), "should not look for delay slot for Null Check" );
1951 assert( !n->is_Catch(), "should not look for delay slot for Catch" );
1952
1953 #ifndef PRODUCT
1954 _branches++;
1955 #endif
1956
1957 // At least 1 instruction is on the available list
1958 // that is not dependent on the branch
1959 for (uint i = 0; i < siz; i++) {
1960 Node *d = _available[i];
1961 const Pipeline *avail_pipeline = d->pipeline();
1962
1963 // Don't allow safepoints in the branch shadow, that will
1964 // cause a number of difficulties
1965 if ( avail_pipeline->instructionCount() == 1 &&
1966 !avail_pipeline->hasMultipleBundles() &&
1967 !avail_pipeline->hasBranchDelay() &&
1968 Pipeline::instr_has_unit_size() &&
1969 d->size(_regalloc) == Pipeline::instr_unit_size() &&
1970 NodeFitsInBundle(d) &&
1971 !node_bundling(d)->used_in_delay()) {
1972
1973 if (d->is_Mach() && !d->is_MachSafePoint()) {
1974 // A node that fits in the delay slot was found, so we need to
1975 // set the appropriate bits in the bundle pipeline information so
1976 // that it correctly indicates resource usage. Later, when we
1977 // attempt to add this instruction to the bundle, we will skip
1978 // setting the resource usage.
1979 _unconditional_delay_slot = d;
1980 node_bundling(n)->set_use_unconditional_delay();
1981 node_bundling(d)->set_used_in_unconditional_delay();
1982 _bundle_use.add_usage(avail_pipeline->resourceUse());
1983 _current_latency[d->_idx] = _bundle_cycle_number;
1984 _next_node = d;
1985 ++_bundle_instr_count;
1986 #ifndef PRODUCT
1987 _unconditional_delays++;
1988 #endif
1989 break;
1990 }
1991 }
1992 }
1993 }
1994
1995 // No delay slot, add a nop to the usage
1996 if (!_unconditional_delay_slot) {
1997 // See if adding an instruction in the delay slot will overflow
1998 // the bundle.
1999 if (!NodeFitsInBundle(_nop)) {
2000 #ifndef PRODUCT
2001 if (_cfg->C->trace_opto_output())
2002 tty->print("# *** STEP(1 instruction for delay slot) ***\n");
2003 #endif
2004 step(1);
2005 }
2006
2007 _bundle_use.add_usage(_nop->pipeline()->resourceUse());
2008 _next_node = _nop;
2009 ++_bundle_instr_count;
2010 }
2011
2012 // See if the instruction in the delay slot requires a
2013 // step of the bundles
2014 if (!NodeFitsInBundle(n)) {
2015 #ifndef PRODUCT
2016 if (_cfg->C->trace_opto_output())
2017 tty->print("# *** STEP(branch won't fit) ***\n");
2018 #endif
2019 // Update the state information
2020 _bundle_instr_count = 0;
2021 _bundle_cycle_number += 1;
2022 _bundle_use.step(1);
2023 }
2024 }
2025
2026 // Get the number of instructions
2027 uint instruction_count = node_pipeline->instructionCount();
2028 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0)
2029 instruction_count = 0;
2030
2031 // Compute the latency information
2032 uint delay = 0;
2033
2034 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) {
2035 int relative_latency = _current_latency[n->_idx] - _bundle_cycle_number;
2036 if (relative_latency < 0)
2037 relative_latency = 0;
2038
2039 delay = _bundle_use.full_latency(relative_latency, node_usage);
2040
2041 // Does not fit in this bundle, start a new one
2042 if (delay > 0) {
2043 step(delay);
2044
2045 #ifndef PRODUCT
2046 if (_cfg->C->trace_opto_output())
2047 tty->print("# *** STEP(%d) ***\n", delay);
2048 #endif
2049 }
2050 }
2051
2052 // If this was placed in the delay slot, ignore it
2053 if (n != _unconditional_delay_slot) {
2054
2055 if (delay == 0) {
2056 if (node_pipeline->hasMultipleBundles()) {
2057 #ifndef PRODUCT
2058 if (_cfg->C->trace_opto_output())
2059 tty->print("# *** STEP(multiple instructions) ***\n");
2060 #endif
2061 step(1);
2062 }
2063
2064 else if (instruction_count + _bundle_instr_count > Pipeline::_max_instrs_per_cycle) {
2065 #ifndef PRODUCT
2066 if (_cfg->C->trace_opto_output())
2067 tty->print("# *** STEP(%d >= %d instructions) ***\n",
2068 instruction_count + _bundle_instr_count,
2069 Pipeline::_max_instrs_per_cycle);
2070 #endif
2071 step(1);
2072 }
2073 }
2074
2075 if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot)
2076 _bundle_instr_count++;
2077
2078 // Set the node's latency
2079 _current_latency[n->_idx] = _bundle_cycle_number;
2080
2081 // Now merge the functional unit information
2082 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode())
2083 _bundle_use.add_usage(node_usage);
2084
2085 // Increment the number of instructions in this bundle
2086 _bundle_instr_count += instruction_count;
2087
2088 // Remember this node for later
2089 if (n->is_Mach())
2090 _next_node = n;
2091 }
2092
2093 // It's possible to have a BoxLock in the graph and in the _bbs mapping but
2094 // not in the bb->_nodes array. This happens for debug-info-only BoxLocks.
2095 // 'Schedule' them (basically ignore in the schedule) but do not insert them
2096 // into the block. All other scheduled nodes get put in the schedule here.
2097 int op = n->Opcode();
2098 if( (op == Op_Node && n->req() == 0) || // anti-dependence node OR
2099 (op != Op_Node && // Not an unused antidepedence node and
2100 // not an unallocated boxlock
2101 (OptoReg::is_valid(_regalloc->get_reg_first(n)) || op != Op_BoxLock)) ) {
2102
2103 // Push any trailing projections
2104 if( bb->_nodes[bb->_nodes.size()-1] != n ) {
2105 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2106 Node *foi = n->fast_out(i);
2107 if( foi->is_Proj() )
2108 _scheduled.push(foi);
2109 }
2110 }
2111
2112 // Put the instruction in the schedule list
2113 _scheduled.push(n);
2114 }
2115
2116 #ifndef PRODUCT
2117 if (_cfg->C->trace_opto_output())
2118 dump_available();
2119 #endif
2120
2121 // Walk all the definitions, decrementing use counts, and
2122 // if a definition has a 0 use count, place it in the available list.
2123 DecrementUseCounts(n,bb);
2124 }
2125
2126 //------------------------------ComputeUseCount--------------------------------
2127 // This method sets the use count within a basic block. We will ignore all
2128 // uses outside the current basic block. As we are doing a backwards walk,
2129 // any node we reach that has a use count of 0 may be scheduled. This also
2130 // avoids the problem of cyclic references from phi nodes, as long as phi
2131 // nodes are at the front of the basic block. This method also initializes
2132 // the available list to the set of instructions that have no uses within this
2133 // basic block.
2134 void Scheduling::ComputeUseCount(const Block *bb) {
2135 #ifndef PRODUCT
2136 if (_cfg->C->trace_opto_output())
2137 tty->print("# -> ComputeUseCount\n");
2138 #endif
2139
2140 // Clear the list of available and scheduled instructions, just in case
2141 _available.clear();
2142 _scheduled.clear();
2143
2144 // No delay slot specified
2145 _unconditional_delay_slot = NULL;
2146
2147 #ifdef ASSERT
2148 for( uint i=0; i < bb->_nodes.size(); i++ )
2149 assert( _uses[bb->_nodes[i]->_idx] == 0, "_use array not clean" );
2150 #endif
2151
2152 // Force the _uses count to never go to zero for unscheduable pieces
2153 // of the block
2154 for( uint k = 0; k < _bb_start; k++ )
2155 _uses[bb->_nodes[k]->_idx] = 1;
2156 for( uint l = _bb_end; l < bb->_nodes.size(); l++ )
2157 _uses[bb->_nodes[l]->_idx] = 1;
2158
2159 // Iterate backwards over the instructions in the block. Don't count the
2160 // branch projections at end or the block header instructions.
2161 for( uint j = _bb_end-1; j >= _bb_start; j-- ) {
2162 Node *n = bb->_nodes[j];
2163 if( n->is_Proj() ) continue; // Projections handled another way
2164
2165 // Account for all uses
2166 for ( uint k = 0; k < n->len(); k++ ) {
2167 Node *inp = n->in(k);
2168 if (!inp) continue;
2169 assert(inp != n, "no cycles allowed" );
2170 if( _bbs[inp->_idx] == bb ) { // Block-local use?
2171 if( inp->is_Proj() ) // Skip through Proj's
2172 inp = inp->in(0);
2173 ++_uses[inp->_idx]; // Count 1 block-local use
2174 }
2175 }
2176
2177 // If this instruction has a 0 use count, then it is available
2178 if (!_uses[n->_idx]) {
2179 _current_latency[n->_idx] = _bundle_cycle_number;
2180 AddNodeToAvailableList(n);
2181 }
2182
2183 #ifndef PRODUCT
2184 if (_cfg->C->trace_opto_output()) {
2185 tty->print("# uses: %3d: ", _uses[n->_idx]);
2186 n->dump();
2187 }
2188 #endif
2189 }
2190
2191 #ifndef PRODUCT
2192 if (_cfg->C->trace_opto_output())
2193 tty->print("# <- ComputeUseCount\n");
2194 #endif
2195 }
2196
2197 // This routine performs scheduling on each basic block in reverse order,
2198 // using instruction latencies and taking into account function unit
2199 // availability.
2200 void Scheduling::DoScheduling() {
2201 #ifndef PRODUCT
2202 if (_cfg->C->trace_opto_output())
2203 tty->print("# -> DoScheduling\n");
2204 #endif
2205
2206 Block *succ_bb = NULL;
2207 Block *bb;
2208
2209 // Walk over all the basic blocks in reverse order
2210 for( int i=_cfg->_num_blocks-1; i >= 0; succ_bb = bb, i-- ) {
2211 bb = _cfg->_blocks[i];
2212
2213 #ifndef PRODUCT
2214 if (_cfg->C->trace_opto_output()) {
2215 tty->print("# Schedule BB#%03d (initial)\n", i);
2216 for (uint j = 0; j < bb->_nodes.size(); j++)
2217 bb->_nodes[j]->dump();
2218 }
2219 #endif
2220
2221 // On the head node, skip processing
2222 if( bb == _cfg->_broot )
2223 continue;
2224
2225 // Skip empty, connector blocks
2226 if (bb->is_connector())
2227 continue;
2228
2229 // If the following block is not the sole successor of
2230 // this one, then reset the pipeline information
2231 if (bb->_num_succs != 1 || bb->non_connector_successor(0) != succ_bb) {
2232 #ifndef PRODUCT
2233 if (_cfg->C->trace_opto_output()) {
2234 tty->print("*** bundle start of next BB, node %d, for %d instructions\n",
2235 _next_node->_idx, _bundle_instr_count);
2236 }
2237 #endif
2238 step_and_clear();
2239 }
2240
2241 // Leave untouched the starting instruction, any Phis, a CreateEx node
2242 // or Top. bb->_nodes[_bb_start] is the first schedulable instruction.
2243 _bb_end = bb->_nodes.size()-1;
2244 for( _bb_start=1; _bb_start <= _bb_end; _bb_start++ ) {
2245 Node *n = bb->_nodes[_bb_start];
2246 // Things not matched, like Phinodes and ProjNodes don't get scheduled.
2247 // Also, MachIdealNodes do not get scheduled
2248 if( !n->is_Mach() ) continue; // Skip non-machine nodes
2249 MachNode *mach = n->as_Mach();
2250 int iop = mach->ideal_Opcode();
2251 if( iop == Op_CreateEx ) continue; // CreateEx is pinned
2252 if( iop == Op_Con ) continue; // Do not schedule Top
2253 if( iop == Op_Node && // Do not schedule PhiNodes, ProjNodes
2254 mach->pipeline() == MachNode::pipeline_class() &&
2255 !n->is_SpillCopy() ) // Breakpoints, Prolog, etc
2256 continue;
2257 break; // Funny loop structure to be sure...
2258 }
2259 // Compute last "interesting" instruction in block - last instruction we
2260 // might schedule. _bb_end points just after last schedulable inst. We
2261 // normally schedule conditional branches (despite them being forced last
2262 // in the block), because they have delay slots we can fill. Calls all
2263 // have their delay slots filled in the template expansions, so we don't
2264 // bother scheduling them.
2265 Node *last = bb->_nodes[_bb_end];
2266 if( last->is_Catch() ||
2267 // Exclude unreachable path case when Halt node is in a separate block.
2268 (_bb_end > 1 && last->is_Mach() && last->as_Mach()->ideal_Opcode() == Op_Halt) ) {
2269 // There must be a prior call. Skip it.
2270 while( !bb->_nodes[--_bb_end]->is_Call() ) {
2271 assert( bb->_nodes[_bb_end]->is_Proj(), "skipping projections after expected call" );
2272 }
2273 } else if( last->is_MachNullCheck() ) {
2274 // Backup so the last null-checked memory instruction is
2275 // outside the schedulable range. Skip over the nullcheck,
2276 // projection, and the memory nodes.
2277 Node *mem = last->in(1);
2278 do {
2279 _bb_end--;
2280 } while (mem != bb->_nodes[_bb_end]);
2281 } else {
2282 // Set _bb_end to point after last schedulable inst.
2283 _bb_end++;
2284 }
2285
2286 assert( _bb_start <= _bb_end, "inverted block ends" );
2287
2288 // Compute the register antidependencies for the basic block
2289 ComputeRegisterAntidependencies(bb);
2290 if (_cfg->C->failing()) return; // too many D-U pinch points
2291
2292 // Compute intra-bb latencies for the nodes
2293 ComputeLocalLatenciesForward(bb);
2294
2295 // Compute the usage within the block, and set the list of all nodes
2296 // in the block that have no uses within the block.
2297 ComputeUseCount(bb);
2298
2299 // Schedule the remaining instructions in the block
2300 while ( _available.size() > 0 ) {
2301 Node *n = ChooseNodeToBundle();
2302 AddNodeToBundle(n,bb);
2303 }
2304
2305 assert( _scheduled.size() == _bb_end - _bb_start, "wrong number of instructions" );
2306 #ifdef ASSERT
2307 for( uint l = _bb_start; l < _bb_end; l++ ) {
2308 Node *n = bb->_nodes[l];
2309 uint m;
2310 for( m = 0; m < _bb_end-_bb_start; m++ )
2311 if( _scheduled[m] == n )
2312 break;
2313 assert( m < _bb_end-_bb_start, "instruction missing in schedule" );
2314 }
2315 #endif
2316
2317 // Now copy the instructions (in reverse order) back to the block
2318 for ( uint k = _bb_start; k < _bb_end; k++ )
2319 bb->_nodes.map(k, _scheduled[_bb_end-k-1]);
2320
2321 #ifndef PRODUCT
2322 if (_cfg->C->trace_opto_output()) {
2323 tty->print("# Schedule BB#%03d (final)\n", i);
2324 uint current = 0;
2325 for (uint j = 0; j < bb->_nodes.size(); j++) {
2326 Node *n = bb->_nodes[j];
2327 if( valid_bundle_info(n) ) {
2328 Bundle *bundle = node_bundling(n);
2329 if (bundle->instr_count() > 0 || bundle->flags() > 0) {
2330 tty->print("*** Bundle: ");
2331 bundle->dump();
2332 }
2333 n->dump();
2334 }
2335 }
2336 }
2337 #endif
2338 #ifdef ASSERT
2339 verify_good_schedule(bb,"after block local scheduling");
2340 #endif
2341 }
2342
2343 #ifndef PRODUCT
2344 if (_cfg->C->trace_opto_output())
2345 tty->print("# <- DoScheduling\n");
2346 #endif
2347
2348 // Record final node-bundling array location
2349 _regalloc->C->set_node_bundling_base(_node_bundling_base);
2350
2351 } // end DoScheduling
2352
2353 //------------------------------verify_good_schedule---------------------------
2354 // Verify that no live-range used in the block is killed in the block by a
2355 // wrong DEF. This doesn't verify live-ranges that span blocks.
2356
2357 // Check for edge existence. Used to avoid adding redundant precedence edges.
2358 static bool edge_from_to( Node *from, Node *to ) {
2359 for( uint i=0; i<from->len(); i++ )
2360 if( from->in(i) == to )
2361 return true;
2362 return false;
2363 }
2364
2365 #ifdef ASSERT
2366 //------------------------------verify_do_def----------------------------------
2367 void Scheduling::verify_do_def( Node *n, OptoReg::Name def, const char *msg ) {
2368 // Check for bad kills
2369 if( OptoReg::is_valid(def) ) { // Ignore stores & control flow
2370 Node *prior_use = _reg_node[def];
2371 if( prior_use && !edge_from_to(prior_use,n) ) {
2372 tty->print("%s = ",OptoReg::as_VMReg(def)->name());
2373 n->dump();
2374 tty->print_cr("...");
2375 prior_use->dump();
2376 assert_msg(edge_from_to(prior_use,n),msg);
2377 }
2378 _reg_node.map(def,NULL); // Kill live USEs
2379 }
2380 }
2381
2382 //------------------------------verify_good_schedule---------------------------
2383 void Scheduling::verify_good_schedule( Block *b, const char *msg ) {
2384
2385 // Zap to something reasonable for the verify code
2386 _reg_node.clear();
2387
2388 // Walk over the block backwards. Check to make sure each DEF doesn't
2389 // kill a live value (other than the one it's supposed to). Add each
2390 // USE to the live set.
2391 for( uint i = b->_nodes.size()-1; i >= _bb_start; i-- ) {
2392 Node *n = b->_nodes[i];
2393 int n_op = n->Opcode();
2394 if( n_op == Op_MachProj && n->ideal_reg() == MachProjNode::fat_proj ) {
2395 // Fat-proj kills a slew of registers
2396 RegMask rm = n->out_RegMask();// Make local copy
2397 while( rm.is_NotEmpty() ) {
2398 OptoReg::Name kill = rm.find_first_elem();
2399 rm.Remove(kill);
2400 verify_do_def( n, kill, msg );
2401 }
2402 } else if( n_op != Op_Node ) { // Avoid brand new antidependence nodes
2403 // Get DEF'd registers the normal way
2404 verify_do_def( n, _regalloc->get_reg_first(n), msg );
2405 verify_do_def( n, _regalloc->get_reg_second(n), msg );
2406 }
2407
2408 // Now make all USEs live
2409 for( uint i=1; i<n->req(); i++ ) {
2410 Node *def = n->in(i);
2411 assert(def != 0, "input edge required");
2412 OptoReg::Name reg_lo = _regalloc->get_reg_first(def);
2413 OptoReg::Name reg_hi = _regalloc->get_reg_second(def);
2414 if( OptoReg::is_valid(reg_lo) ) {
2415 assert_msg(!_reg_node[reg_lo] || edge_from_to(_reg_node[reg_lo],def), msg );
2416 _reg_node.map(reg_lo,n);
2417 }
2418 if( OptoReg::is_valid(reg_hi) ) {
2419 assert_msg(!_reg_node[reg_hi] || edge_from_to(_reg_node[reg_hi],def), msg );
2420 _reg_node.map(reg_hi,n);
2421 }
2422 }
2423
2424 }
2425
2426 // Zap to something reasonable for the Antidependence code
2427 _reg_node.clear();
2428 }
2429 #endif
2430
2431 // Conditionally add precedence edges. Avoid putting edges on Projs.
2432 static void add_prec_edge_from_to( Node *from, Node *to ) {
2433 if( from->is_Proj() ) { // Put precedence edge on Proj's input
2434 assert( from->req() == 1 && (from->len() == 1 || from->in(1)==0), "no precedence edges on projections" );
2435 from = from->in(0);
2436 }
2437 if( from != to && // No cycles (for things like LD L0,[L0+4] )
2438 !edge_from_to( from, to ) ) // Avoid duplicate edge
2439 from->add_prec(to);
2440 }
2441
2442 //------------------------------anti_do_def------------------------------------
2443 void Scheduling::anti_do_def( Block *b, Node *def, OptoReg::Name def_reg, int is_def ) {
2444 if( !OptoReg::is_valid(def_reg) ) // Ignore stores & control flow
2445 return;
2446
2447 Node *pinch = _reg_node[def_reg]; // Get pinch point
2448 if( !pinch || _bbs[pinch->_idx] != b || // No pinch-point yet?
2449 is_def ) { // Check for a true def (not a kill)
2450 _reg_node.map(def_reg,def); // Record def/kill as the optimistic pinch-point
2451 return;
2452 }
2453
2454 Node *kill = def; // Rename 'def' to more descriptive 'kill'
2455 debug_only( def = (Node*)0xdeadbeef; )
2456
2457 // After some number of kills there _may_ be a later def
2458 Node *later_def = NULL;
2459
2460 // Finding a kill requires a real pinch-point.
2461 // Check for not already having a pinch-point.
2462 // Pinch points are Op_Node's.
2463 if( pinch->Opcode() != Op_Node ) { // Or later-def/kill as pinch-point?
2464 later_def = pinch; // Must be def/kill as optimistic pinch-point
2465 if ( _pinch_free_list.size() > 0) {
2466 pinch = _pinch_free_list.pop();
2467 } else {
2468 pinch = new (_cfg->C, 1) Node(1); // Pinch point to-be
2469 }
2470 if (pinch->_idx >= _regalloc->node_regs_max_index()) {
2471 _cfg->C->record_method_not_compilable("too many D-U pinch points");
2472 return;
2473 }
2474 _bbs.map(pinch->_idx,b); // Pretend it's valid in this block (lazy init)
2475 _reg_node.map(def_reg,pinch); // Record pinch-point
2476 //_regalloc->set_bad(pinch->_idx); // Already initialized this way.
2477 if( later_def->outcnt() == 0 || later_def->ideal_reg() == MachProjNode::fat_proj ) { // Distinguish def from kill
2478 pinch->init_req(0, _cfg->C->top()); // set not NULL for the next call
2479 add_prec_edge_from_to(later_def,pinch); // Add edge from kill to pinch
2480 later_def = NULL; // and no later def
2481 }
2482 pinch->set_req(0,later_def); // Hook later def so we can find it
2483 } else { // Else have valid pinch point
2484 if( pinch->in(0) ) // If there is a later-def
2485 later_def = pinch->in(0); // Get it
2486 }
2487
2488 // Add output-dependence edge from later def to kill
2489 if( later_def ) // If there is some original def
2490 add_prec_edge_from_to(later_def,kill); // Add edge from def to kill
2491
2492 // See if current kill is also a use, and so is forced to be the pinch-point.
2493 if( pinch->Opcode() == Op_Node ) {
2494 Node *uses = kill->is_Proj() ? kill->in(0) : kill;
2495 for( uint i=1; i<uses->req(); i++ ) {
2496 if( _regalloc->get_reg_first(uses->in(i)) == def_reg ||
2497 _regalloc->get_reg_second(uses->in(i)) == def_reg ) {
2498 // Yes, found a use/kill pinch-point
2499 pinch->set_req(0,NULL); //
2500 pinch->replace_by(kill); // Move anti-dep edges up
2501 pinch = kill;
2502 _reg_node.map(def_reg,pinch);
2503 return;
2504 }
2505 }
2506 }
2507
2508 // Add edge from kill to pinch-point
2509 add_prec_edge_from_to(kill,pinch);
2510 }
2511
2512 //------------------------------anti_do_use------------------------------------
2513 void Scheduling::anti_do_use( Block *b, Node *use, OptoReg::Name use_reg ) {
2514 if( !OptoReg::is_valid(use_reg) ) // Ignore stores & control flow
2515 return;
2516 Node *pinch = _reg_node[use_reg]; // Get pinch point
2517 // Check for no later def_reg/kill in block
2518 if( pinch && _bbs[pinch->_idx] == b &&
2519 // Use has to be block-local as well
2520 _bbs[use->_idx] == b ) {
2521 if( pinch->Opcode() == Op_Node && // Real pinch-point (not optimistic?)
2522 pinch->req() == 1 ) { // pinch not yet in block?
2523 pinch->del_req(0); // yank pointer to later-def, also set flag
2524 // Insert the pinch-point in the block just after the last use
2525 b->_nodes.insert(b->find_node(use)+1,pinch);
2526 _bb_end++; // Increase size scheduled region in block
2527 }
2528
2529 add_prec_edge_from_to(pinch,use);
2530 }
2531 }
2532
2533 //------------------------------ComputeRegisterAntidependences-----------------
2534 // We insert antidependences between the reads and following write of
2535 // allocated registers to prevent illegal code motion. Hopefully, the
2536 // number of added references should be fairly small, especially as we
2537 // are only adding references within the current basic block.
2538 void Scheduling::ComputeRegisterAntidependencies(Block *b) {
2539
2540 #ifdef ASSERT
2541 verify_good_schedule(b,"before block local scheduling");
2542 #endif
2543
2544 // A valid schedule, for each register independently, is an endless cycle
2545 // of: a def, then some uses (connected to the def by true dependencies),
2546 // then some kills (defs with no uses), finally the cycle repeats with a new
2547 // def. The uses are allowed to float relative to each other, as are the
2548 // kills. No use is allowed to slide past a kill (or def). This requires
2549 // antidependencies between all uses of a single def and all kills that
2550 // follow, up to the next def. More edges are redundant, because later defs
2551 // & kills are already serialized with true or antidependencies. To keep
2552 // the edge count down, we add a 'pinch point' node if there's more than
2553 // one use or more than one kill/def.
2554
2555 // We add dependencies in one bottom-up pass.
2556
2557 // For each instruction we handle it's DEFs/KILLs, then it's USEs.
2558
2559 // For each DEF/KILL, we check to see if there's a prior DEF/KILL for this
2560 // register. If not, we record the DEF/KILL in _reg_node, the
2561 // register-to-def mapping. If there is a prior DEF/KILL, we insert a
2562 // "pinch point", a new Node that's in the graph but not in the block.
2563 // We put edges from the prior and current DEF/KILLs to the pinch point.
2564 // We put the pinch point in _reg_node. If there's already a pinch point
2565 // we merely add an edge from the current DEF/KILL to the pinch point.
2566
2567 // After doing the DEF/KILLs, we handle USEs. For each used register, we
2568 // put an edge from the pinch point to the USE.
2569
2570 // To be expedient, the _reg_node array is pre-allocated for the whole
2571 // compilation. _reg_node is lazily initialized; it either contains a NULL,
2572 // or a valid def/kill/pinch-point, or a leftover node from some prior
2573 // block. Leftover node from some prior block is treated like a NULL (no
2574 // prior def, so no anti-dependence needed). Valid def is distinguished by
2575 // it being in the current block.
2576 bool fat_proj_seen = false;
2577 uint last_safept = _bb_end-1;
2578 Node* end_node = (_bb_end-1 >= _bb_start) ? b->_nodes[last_safept] : NULL;
2579 Node* last_safept_node = end_node;
2580 for( uint i = _bb_end-1; i >= _bb_start; i-- ) {
2581 Node *n = b->_nodes[i];
2582 int is_def = n->outcnt(); // def if some uses prior to adding precedence edges
2583 if( n->Opcode() == Op_MachProj && n->ideal_reg() == MachProjNode::fat_proj ) {
2584 // Fat-proj kills a slew of registers
2585 // This can add edges to 'n' and obscure whether or not it was a def,
2586 // hence the is_def flag.
2587 fat_proj_seen = true;
2588 RegMask rm = n->out_RegMask();// Make local copy
2589 while( rm.is_NotEmpty() ) {
2590 OptoReg::Name kill = rm.find_first_elem();
2591 rm.Remove(kill);
2592 anti_do_def( b, n, kill, is_def );
2593 }
2594 } else {
2595 // Get DEF'd registers the normal way
2596 anti_do_def( b, n, _regalloc->get_reg_first(n), is_def );
2597 anti_do_def( b, n, _regalloc->get_reg_second(n), is_def );
2598 }
2599
2600 // Check each register used by this instruction for a following DEF/KILL
2601 // that must occur afterward and requires an anti-dependence edge.
2602 for( uint j=0; j<n->req(); j++ ) {
2603 Node *def = n->in(j);
2604 if( def ) {
2605 assert( def->Opcode() != Op_MachProj || def->ideal_reg() != MachProjNode::fat_proj, "" );
2606 anti_do_use( b, n, _regalloc->get_reg_first(def) );
2607 anti_do_use( b, n, _regalloc->get_reg_second(def) );
2608 }
2609 }
2610 // Do not allow defs of new derived values to float above GC
2611 // points unless the base is definitely available at the GC point.
2612
2613 Node *m = b->_nodes[i];
2614
2615 // Add precedence edge from following safepoint to use of derived pointer
2616 if( last_safept_node != end_node &&
2617 m != last_safept_node) {
2618 for (uint k = 1; k < m->req(); k++) {
2619 const Type *t = m->in(k)->bottom_type();
2620 if( t->isa_oop_ptr() &&
2621 t->is_ptr()->offset() != 0 ) {
2622 last_safept_node->add_prec( m );
2623 break;
2624 }
2625 }
2626 }
2627
2628 if( n->jvms() ) { // Precedence edge from derived to safept
2629 // Check if last_safept_node was moved by pinch-point insertion in anti_do_use()
2630 if( b->_nodes[last_safept] != last_safept_node ) {
2631 last_safept = b->find_node(last_safept_node);
2632 }
2633 for( uint j=last_safept; j > i; j-- ) {
2634 Node *mach = b->_nodes[j];
2635 if( mach->is_Mach() && mach->as_Mach()->ideal_Opcode() == Op_AddP )
2636 mach->add_prec( n );
2637 }
2638 last_safept = i;
2639 last_safept_node = m;
2640 }
2641 }
2642
2643 if (fat_proj_seen) {
2644 // Garbage collect pinch nodes that were not consumed.
2645 // They are usually created by a fat kill MachProj for a call.
2646 garbage_collect_pinch_nodes();
2647 }
2648 }
2649
2650 //------------------------------garbage_collect_pinch_nodes-------------------------------
2651
2652 // Garbage collect pinch nodes for reuse by other blocks.
2653 //
2654 // The block scheduler's insertion of anti-dependence
2655 // edges creates many pinch nodes when the block contains
2656 // 2 or more Calls. A pinch node is used to prevent a
2657 // combinatorial explosion of edges. If a set of kills for a
2658 // register is anti-dependent on a set of uses (or defs), rather
2659 // than adding an edge in the graph between each pair of kill
2660 // and use (or def), a pinch is inserted between them:
2661 //
2662 // use1 use2 use3
2663 // \ | /
2664 // \ | /
2665 // pinch
2666 // / | \
2667 // / | \
2668 // kill1 kill2 kill3
2669 //
2670 // One pinch node is created per register killed when
2671 // the second call is encountered during a backwards pass
2672 // over the block. Most of these pinch nodes are never
2673 // wired into the graph because the register is never
2674 // used or def'ed in the block.
2675 //
2676 void Scheduling::garbage_collect_pinch_nodes() {
2677 #ifndef PRODUCT
2678 if (_cfg->C->trace_opto_output()) tty->print("Reclaimed pinch nodes:");
2679 #endif
2680 int trace_cnt = 0;
2681 for (uint k = 0; k < _reg_node.Size(); k++) {
2682 Node* pinch = _reg_node[k];
2683 if (pinch != NULL && pinch->Opcode() == Op_Node &&
2684 // no predecence input edges
2685 (pinch->req() == pinch->len() || pinch->in(pinch->req()) == NULL) ) {
2686 cleanup_pinch(pinch);
2687 _pinch_free_list.push(pinch);
2688 _reg_node.map(k, NULL);
2689 #ifndef PRODUCT
2690 if (_cfg->C->trace_opto_output()) {
2691 trace_cnt++;
2692 if (trace_cnt > 40) {
2693 tty->print("\n");
2694 trace_cnt = 0;
2695 }
2696 tty->print(" %d", pinch->_idx);
2697 }
2698 #endif
2699 }
2700 }
2701 #ifndef PRODUCT
2702 if (_cfg->C->trace_opto_output()) tty->print("\n");
2703 #endif
2704 }
2705
2706 // Clean up a pinch node for reuse.
2707 void Scheduling::cleanup_pinch( Node *pinch ) {
2708 assert (pinch && pinch->Opcode() == Op_Node && pinch->req() == 1, "just checking");
2709
2710 for (DUIterator_Last imin, i = pinch->last_outs(imin); i >= imin; ) {
2711 Node* use = pinch->last_out(i);
2712 uint uses_found = 0;
2713 for (uint j = use->req(); j < use->len(); j++) {
2714 if (use->in(j) == pinch) {
2715 use->rm_prec(j);
2716 uses_found++;
2717 }
2718 }
2719 assert(uses_found > 0, "must be a precedence edge");
2720 i -= uses_found; // we deleted 1 or more copies of this edge
2721 }
2722 // May have a later_def entry
2723 pinch->set_req(0, NULL);
2724 }
2725
2726 //------------------------------print_statistics-------------------------------
2727 #ifndef PRODUCT
2728
2729 void Scheduling::dump_available() const {
2730 tty->print("#Availist ");
2731 for (uint i = 0; i < _available.size(); i++)
2732 tty->print(" N%d/l%d", _available[i]->_idx,_current_latency[_available[i]->_idx]);
2733 tty->cr();
2734 }
2735
2736 // Print Scheduling Statistics
2737 void Scheduling::print_statistics() {
2738 // Print the size added by nops for bundling
2739 tty->print("Nops added %d bytes to total of %d bytes",
2740 _total_nop_size, _total_method_size);
2741 if (_total_method_size > 0)
2742 tty->print(", for %.2f%%",
2743 ((double)_total_nop_size) / ((double) _total_method_size) * 100.0);
2744 tty->print("\n");
2745
2746 // Print the number of branch shadows filled
2747 if (Pipeline::_branch_has_delay_slot) {
2748 tty->print("Of %d branches, %d had unconditional delay slots filled",
2749 _total_branches, _total_unconditional_delays);
2750 if (_total_branches > 0)
2751 tty->print(", for %.2f%%",
2752 ((double)_total_unconditional_delays) / ((double)_total_branches) * 100.0);
2753 tty->print("\n");
2754 }
2755
2756 uint total_instructions = 0, total_bundles = 0;
2757
2758 for (uint i = 1; i <= Pipeline::_max_instrs_per_cycle; i++) {
2759 uint bundle_count = _total_instructions_per_bundle[i];
2760 total_instructions += bundle_count * i;
2761 total_bundles += bundle_count;
2762 }
2763
2764 if (total_bundles > 0)
2765 tty->print("Average ILP (excluding nops) is %.2f\n",
2766 ((double)total_instructions) / ((double)total_bundles));
2767 }
2768 #endif