1 /*
2 * Copyright (c) 1998, 2020, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "asm/assembler.inline.hpp"
27 #include "asm/macroAssembler.inline.hpp"
28 #include "code/compiledIC.hpp"
29 #include "code/debugInfo.hpp"
30 #include "code/debugInfoRec.hpp"
31 #include "compiler/compileBroker.hpp"
32 #include "compiler/compilerDirectives.hpp"
33 #include "compiler/oopMap.hpp"
34 #include "gc/shared/barrierSet.hpp"
35 #include "gc/shared/c2/barrierSetC2.hpp"
36 #include "memory/allocation.inline.hpp"
37 #include "opto/ad.hpp"
38 #include "opto/block.hpp"
39 #include "opto/c2compiler.hpp"
40 #include "opto/callnode.hpp"
41 #include "opto/cfgnode.hpp"
42 #include "opto/locknode.hpp"
43 #include "opto/machnode.hpp"
44 #include "opto/node.hpp"
45 #include "opto/optoreg.hpp"
46 #include "opto/output.hpp"
47 #include "opto/regalloc.hpp"
48 #include "opto/runtime.hpp"
49 #include "opto/subnode.hpp"
50 #include "opto/type.hpp"
51 #include "runtime/handles.inline.hpp"
52 #include "runtime/sharedRuntime.hpp"
53 #include "utilities/macros.hpp"
54 #include "utilities/powerOfTwo.hpp"
55 #include "utilities/xmlstream.hpp"
56
57 #ifndef PRODUCT
58 #define DEBUG_ARG(x) , x
59 #else
60 #define DEBUG_ARG(x)
61 #endif
62
63 //------------------------------Scheduling----------------------------------
64 // This class contains all the information necessary to implement instruction
65 // scheduling and bundling.
66 class Scheduling {
67
68 private:
69 // Arena to use
70 Arena *_arena;
71
72 // Control-Flow Graph info
73 PhaseCFG *_cfg;
74
75 // Register Allocation info
76 PhaseRegAlloc *_regalloc;
77
78 // Number of nodes in the method
79 uint _node_bundling_limit;
80
81 // List of scheduled nodes. Generated in reverse order
82 Node_List _scheduled;
83
84 // List of nodes currently available for choosing for scheduling
85 Node_List _available;
86
87 // For each instruction beginning a bundle, the number of following
88 // nodes to be bundled with it.
89 Bundle *_node_bundling_base;
90
91 // Mapping from register to Node
92 Node_List _reg_node;
93
94 // Free list for pinch nodes.
95 Node_List _pinch_free_list;
96
97 // Latency from the beginning of the containing basic block (base 1)
98 // for each node.
99 unsigned short *_node_latency;
100
101 // Number of uses of this node within the containing basic block.
102 short *_uses;
103
104 // Schedulable portion of current block. Skips Region/Phi/CreateEx up
105 // front, branch+proj at end. Also skips Catch/CProj (same as
106 // branch-at-end), plus just-prior exception-throwing call.
107 uint _bb_start, _bb_end;
108
109 // Latency from the end of the basic block as scheduled
110 unsigned short *_current_latency;
111
112 // Remember the next node
113 Node *_next_node;
114
115 // Use this for an unconditional branch delay slot
116 Node *_unconditional_delay_slot;
117
118 // Pointer to a Nop
119 MachNopNode *_nop;
120
121 // Length of the current bundle, in instructions
122 uint _bundle_instr_count;
123
124 // Current Cycle number, for computing latencies and bundling
125 uint _bundle_cycle_number;
126
127 // Bundle information
128 Pipeline_Use_Element _bundle_use_elements[resource_count];
129 Pipeline_Use _bundle_use;
130
131 // Dump the available list
132 void dump_available() const;
133
134 public:
135 Scheduling(Arena *arena, Compile &compile);
136
137 // Destructor
138 NOT_PRODUCT( ~Scheduling(); )
139
140 // Step ahead "i" cycles
141 void step(uint i);
142
143 // Step ahead 1 cycle, and clear the bundle state (for example,
144 // at a branch target)
145 void step_and_clear();
146
147 Bundle* node_bundling(const Node *n) {
148 assert(valid_bundle_info(n), "oob");
149 return (&_node_bundling_base[n->_idx]);
150 }
151
152 bool valid_bundle_info(const Node *n) const {
153 return (_node_bundling_limit > n->_idx);
154 }
155
156 bool starts_bundle(const Node *n) const {
157 return (_node_bundling_limit > n->_idx && _node_bundling_base[n->_idx].starts_bundle());
158 }
159
160 // Do the scheduling
161 void DoScheduling();
162
163 // Compute the local latencies walking forward over the list of
164 // nodes for a basic block
165 void ComputeLocalLatenciesForward(const Block *bb);
166
167 // Compute the register antidependencies within a basic block
168 void ComputeRegisterAntidependencies(Block *bb);
169 void verify_do_def( Node *n, OptoReg::Name def, const char *msg );
170 void verify_good_schedule( Block *b, const char *msg );
171 void anti_do_def( Block *b, Node *def, OptoReg::Name def_reg, int is_def );
172 void anti_do_use( Block *b, Node *use, OptoReg::Name use_reg );
173
174 // Add a node to the current bundle
175 void AddNodeToBundle(Node *n, const Block *bb);
176
177 // Add a node to the list of available nodes
178 void AddNodeToAvailableList(Node *n);
179
180 // Compute the local use count for the nodes in a block, and compute
181 // the list of instructions with no uses in the block as available
182 void ComputeUseCount(const Block *bb);
183
184 // Choose an instruction from the available list to add to the bundle
185 Node * ChooseNodeToBundle();
186
187 // See if this Node fits into the currently accumulating bundle
188 bool NodeFitsInBundle(Node *n);
189
190 // Decrement the use count for a node
191 void DecrementUseCounts(Node *n, const Block *bb);
192
193 // Garbage collect pinch nodes for reuse by other blocks.
194 void garbage_collect_pinch_nodes();
195 // Clean up a pinch node for reuse (helper for above).
196 void cleanup_pinch( Node *pinch );
197
198 // Information for statistics gathering
199 #ifndef PRODUCT
200 private:
201 // Gather information on size of nops relative to total
202 uint _branches, _unconditional_delays;
203
204 static uint _total_nop_size, _total_method_size;
205 static uint _total_branches, _total_unconditional_delays;
206 static uint _total_instructions_per_bundle[Pipeline::_max_instrs_per_cycle+1];
207
208 public:
209 static void print_statistics();
210
211 static void increment_instructions_per_bundle(uint i) {
212 _total_instructions_per_bundle[i]++;
213 }
214
215 static void increment_nop_size(uint s) {
216 _total_nop_size += s;
217 }
218
219 static void increment_method_size(uint s) {
220 _total_method_size += s;
221 }
222 #endif
223
224 };
225
226
227 PhaseOutput::PhaseOutput()
228 : Phase(Phase::Output),
229 _code_buffer("Compile::Fill_buffer"),
230 _first_block_size(0),
231 _handler_table(),
232 _inc_table(),
233 _oop_map_set(NULL),
234 _scratch_buffer_blob(NULL),
235 _scratch_locs_memory(NULL),
236 _scratch_const_size(-1),
237 _in_scratch_emit_size(false),
238 _frame_slots(0),
239 _code_offsets(),
240 _node_bundling_limit(0),
241 _node_bundling_base(NULL),
242 _orig_pc_slot(0),
243 _orig_pc_slot_offset_in_bytes(0),
244 _buf_sizes(),
245 _block(NULL),
246 _index(0) {
247 C->set_output(this);
248 if (C->stub_name() == NULL) {
249 _orig_pc_slot = C->fixed_slots() - (sizeof(address) / VMRegImpl::stack_slot_size);
250 }
251 }
252
253 PhaseOutput::~PhaseOutput() {
254 C->set_output(NULL);
255 if (_scratch_buffer_blob != NULL) {
256 BufferBlob::free(_scratch_buffer_blob);
257 }
258 }
259
260 void PhaseOutput::perform_mach_node_analysis() {
261 // Late barrier analysis must be done after schedule and bundle
262 // Otherwise liveness based spilling will fail
263 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
264 bs->late_barrier_analysis();
265
266 pd_perform_mach_node_analysis();
267 }
268
269 // Convert Nodes to instruction bits and pass off to the VM
270 void PhaseOutput::Output() {
271 // RootNode goes
272 assert( C->cfg()->get_root_block()->number_of_nodes() == 0, "" );
273
274 // The number of new nodes (mostly MachNop) is proportional to
275 // the number of java calls and inner loops which are aligned.
276 if ( C->check_node_count((NodeLimitFudgeFactor + C->java_calls()*3 +
277 C->inner_loops()*(OptoLoopAlignment-1)),
278 "out of nodes before code generation" ) ) {
279 return;
280 }
281 // Make sure I can find the Start Node
282 Block *entry = C->cfg()->get_block(1);
283 Block *broot = C->cfg()->get_root_block();
284
285 const StartNode *start = entry->head()->as_Start();
286
287 // Replace StartNode with prolog
288 MachPrologNode *prolog = new MachPrologNode();
289 entry->map_node(prolog, 0);
290 C->cfg()->map_node_to_block(prolog, entry);
291 C->cfg()->unmap_node_from_block(start); // start is no longer in any block
292
293 // Virtual methods need an unverified entry point
294
295 if( C->is_osr_compilation() ) {
296 if( PoisonOSREntry ) {
297 // TODO: Should use a ShouldNotReachHereNode...
298 C->cfg()->insert( broot, 0, new MachBreakpointNode() );
299 }
300 } else {
301 if( C->method() && !C->method()->flags().is_static() ) {
302 // Insert unvalidated entry point
303 C->cfg()->insert( broot, 0, new MachUEPNode() );
304 }
305
306 }
307
308 // Break before main entry point
309 if ((C->method() && C->directive()->BreakAtExecuteOption) ||
310 (OptoBreakpoint && C->is_method_compilation()) ||
311 (OptoBreakpointOSR && C->is_osr_compilation()) ||
312 (OptoBreakpointC2R && !C->method()) ) {
313 // checking for C->method() means that OptoBreakpoint does not apply to
314 // runtime stubs or frame converters
315 C->cfg()->insert( entry, 1, new MachBreakpointNode() );
316 }
317
318 // Insert epilogs before every return
319 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) {
320 Block* block = C->cfg()->get_block(i);
321 if (!block->is_connector() && block->non_connector_successor(0) == C->cfg()->get_root_block()) { // Found a program exit point?
322 Node* m = block->end();
323 if (m->is_Mach() && m->as_Mach()->ideal_Opcode() != Op_Halt) {
324 MachEpilogNode* epilog = new MachEpilogNode(m->as_Mach()->ideal_Opcode() == Op_Return);
325 block->add_inst(epilog);
326 C->cfg()->map_node_to_block(epilog, block);
327 }
328 }
329 }
330
331 // Keeper of sizing aspects
332 _buf_sizes = BufferSizingData();
333
334 // Initialize code buffer
335 estimate_buffer_size(_buf_sizes._const);
336 if (C->failing()) return;
337
338 // Pre-compute the length of blocks and replace
339 // long branches with short if machine supports it.
340 // Must be done before ScheduleAndBundle due to SPARC delay slots
341 uint* blk_starts = NEW_RESOURCE_ARRAY(uint, C->cfg()->number_of_blocks() + 1);
342 blk_starts[0] = 0;
343 shorten_branches(blk_starts);
344
345 ScheduleAndBundle();
346 if (C->failing()) {
347 return;
348 }
349
350 perform_mach_node_analysis();
351
352 // Complete sizing of codebuffer
353 CodeBuffer* cb = init_buffer();
354 if (cb == NULL || C->failing()) {
355 return;
356 }
357
358 BuildOopMaps();
359
360 if (C->failing()) {
361 return;
362 }
363
364 fill_buffer(cb, blk_starts);
365 }
366
367 bool PhaseOutput::need_stack_bang(int frame_size_in_bytes) const {
368 // Determine if we need to generate a stack overflow check.
369 // Do it if the method is not a stub function and
370 // has java calls or has frame size > vm_page_size/8.
371 // The debug VM checks that deoptimization doesn't trigger an
372 // unexpected stack overflow (compiled method stack banging should
373 // guarantee it doesn't happen) so we always need the stack bang in
374 // a debug VM.
375 return (UseStackBanging && C->stub_function() == NULL &&
376 (C->has_java_calls() || frame_size_in_bytes > os::vm_page_size()>>3
377 DEBUG_ONLY(|| true)));
378 }
379
380 bool PhaseOutput::need_register_stack_bang() const {
381 // Determine if we need to generate a register stack overflow check.
382 // This is only used on architectures which have split register
383 // and memory stacks (ie. IA64).
384 // Bang if the method is not a stub function and has java calls
385 return (C->stub_function() == NULL && C->has_java_calls());
386 }
387
388
389 // Compute the size of first NumberOfLoopInstrToAlign instructions at the top
390 // of a loop. When aligning a loop we need to provide enough instructions
391 // in cpu's fetch buffer to feed decoders. The loop alignment could be
392 // avoided if we have enough instructions in fetch buffer at the head of a loop.
393 // By default, the size is set to 999999 by Block's constructor so that
394 // a loop will be aligned if the size is not reset here.
395 //
396 // Note: Mach instructions could contain several HW instructions
397 // so the size is estimated only.
398 //
399 void PhaseOutput::compute_loop_first_inst_sizes() {
400 // The next condition is used to gate the loop alignment optimization.
401 // Don't aligned a loop if there are enough instructions at the head of a loop
402 // or alignment padding is larger then MaxLoopPad. By default, MaxLoopPad
403 // is equal to OptoLoopAlignment-1 except on new Intel cpus, where it is
404 // equal to 11 bytes which is the largest address NOP instruction.
405 if (MaxLoopPad < OptoLoopAlignment - 1) {
406 uint last_block = C->cfg()->number_of_blocks() - 1;
407 for (uint i = 1; i <= last_block; i++) {
408 Block* block = C->cfg()->get_block(i);
409 // Check the first loop's block which requires an alignment.
410 if (block->loop_alignment() > (uint)relocInfo::addr_unit()) {
411 uint sum_size = 0;
412 uint inst_cnt = NumberOfLoopInstrToAlign;
413 inst_cnt = block->compute_first_inst_size(sum_size, inst_cnt, C->regalloc());
414
415 // Check subsequent fallthrough blocks if the loop's first
416 // block(s) does not have enough instructions.
417 Block *nb = block;
418 while(inst_cnt > 0 &&
419 i < last_block &&
420 !C->cfg()->get_block(i + 1)->has_loop_alignment() &&
421 !nb->has_successor(block)) {
422 i++;
423 nb = C->cfg()->get_block(i);
424 inst_cnt = nb->compute_first_inst_size(sum_size, inst_cnt, C->regalloc());
425 } // while( inst_cnt > 0 && i < last_block )
426
427 block->set_first_inst_size(sum_size);
428 } // f( b->head()->is_Loop() )
429 } // for( i <= last_block )
430 } // if( MaxLoopPad < OptoLoopAlignment-1 )
431 }
432
433 // The architecture description provides short branch variants for some long
434 // branch instructions. Replace eligible long branches with short branches.
435 void PhaseOutput::shorten_branches(uint* blk_starts) {
436 // Compute size of each block, method size, and relocation information size
437 uint nblocks = C->cfg()->number_of_blocks();
438
439 uint* jmp_offset = NEW_RESOURCE_ARRAY(uint,nblocks);
440 uint* jmp_size = NEW_RESOURCE_ARRAY(uint,nblocks);
441 int* jmp_nidx = NEW_RESOURCE_ARRAY(int ,nblocks);
442
443 // Collect worst case block paddings
444 int* block_worst_case_pad = NEW_RESOURCE_ARRAY(int, nblocks);
445 memset(block_worst_case_pad, 0, nblocks * sizeof(int));
446
447 DEBUG_ONLY( uint *jmp_target = NEW_RESOURCE_ARRAY(uint,nblocks); )
448 DEBUG_ONLY( uint *jmp_rule = NEW_RESOURCE_ARRAY(uint,nblocks); )
449
450 bool has_short_branch_candidate = false;
451
452 // Initialize the sizes to 0
453 int code_size = 0; // Size in bytes of generated code
454 int stub_size = 0; // Size in bytes of all stub entries
455 // Size in bytes of all relocation entries, including those in local stubs.
456 // Start with 2-bytes of reloc info for the unvalidated entry point
457 int reloc_size = 1; // Number of relocation entries
458
459 // Make three passes. The first computes pessimistic blk_starts,
460 // relative jmp_offset and reloc_size information. The second performs
461 // short branch substitution using the pessimistic sizing. The
462 // third inserts nops where needed.
463
464 // Step one, perform a pessimistic sizing pass.
465 uint last_call_adr = max_juint;
466 uint last_avoid_back_to_back_adr = max_juint;
467 uint nop_size = (new MachNopNode())->size(C->regalloc());
468 for (uint i = 0; i < nblocks; i++) { // For all blocks
469 Block* block = C->cfg()->get_block(i);
470 _block = block;
471
472 // During short branch replacement, we store the relative (to blk_starts)
473 // offset of jump in jmp_offset, rather than the absolute offset of jump.
474 // This is so that we do not need to recompute sizes of all nodes when
475 // we compute correct blk_starts in our next sizing pass.
476 jmp_offset[i] = 0;
477 jmp_size[i] = 0;
478 jmp_nidx[i] = -1;
479 DEBUG_ONLY( jmp_target[i] = 0; )
480 DEBUG_ONLY( jmp_rule[i] = 0; )
481
482 // Sum all instruction sizes to compute block size
483 uint last_inst = block->number_of_nodes();
484 uint blk_size = 0;
485 for (uint j = 0; j < last_inst; j++) {
486 _index = j;
487 Node* nj = block->get_node(_index);
488 // Handle machine instruction nodes
489 if (nj->is_Mach()) {
490 MachNode* mach = nj->as_Mach();
491 blk_size += (mach->alignment_required() - 1) * relocInfo::addr_unit(); // assume worst case padding
492 reloc_size += mach->reloc();
493 if (mach->is_MachCall()) {
494 // add size information for trampoline stub
495 // class CallStubImpl is platform-specific and defined in the *.ad files.
496 stub_size += CallStubImpl::size_call_trampoline();
497 reloc_size += CallStubImpl::reloc_call_trampoline();
498
499 MachCallNode *mcall = mach->as_MachCall();
500 // This destination address is NOT PC-relative
501
502 mcall->method_set((intptr_t)mcall->entry_point());
503
504 if (mcall->is_MachCallJava() && mcall->as_MachCallJava()->_method) {
505 stub_size += CompiledStaticCall::to_interp_stub_size();
506 reloc_size += CompiledStaticCall::reloc_to_interp_stub();
507 #if INCLUDE_AOT
508 stub_size += CompiledStaticCall::to_aot_stub_size();
509 reloc_size += CompiledStaticCall::reloc_to_aot_stub();
510 #endif
511 }
512 } else if (mach->is_MachSafePoint()) {
513 // If call/safepoint are adjacent, account for possible
514 // nop to disambiguate the two safepoints.
515 // ScheduleAndBundle() can rearrange nodes in a block,
516 // check for all offsets inside this block.
517 if (last_call_adr >= blk_starts[i]) {
518 blk_size += nop_size;
519 }
520 }
521 if (mach->avoid_back_to_back(MachNode::AVOID_BEFORE)) {
522 // Nop is inserted between "avoid back to back" instructions.
523 // ScheduleAndBundle() can rearrange nodes in a block,
524 // check for all offsets inside this block.
525 if (last_avoid_back_to_back_adr >= blk_starts[i]) {
526 blk_size += nop_size;
527 }
528 }
529 if (mach->may_be_short_branch()) {
530 if (!nj->is_MachBranch()) {
531 #ifndef PRODUCT
532 nj->dump(3);
533 #endif
534 Unimplemented();
535 }
536 assert(jmp_nidx[i] == -1, "block should have only one branch");
537 jmp_offset[i] = blk_size;
538 jmp_size[i] = nj->size(C->regalloc());
539 jmp_nidx[i] = j;
540 has_short_branch_candidate = true;
541 }
542 }
543 blk_size += nj->size(C->regalloc());
544 // Remember end of call offset
545 if (nj->is_MachCall() && !nj->is_MachCallLeaf()) {
546 last_call_adr = blk_starts[i]+blk_size;
547 }
548 // Remember end of avoid_back_to_back offset
549 if (nj->is_Mach() && nj->as_Mach()->avoid_back_to_back(MachNode::AVOID_AFTER)) {
550 last_avoid_back_to_back_adr = blk_starts[i]+blk_size;
551 }
552 }
553
554 // When the next block starts a loop, we may insert pad NOP
555 // instructions. Since we cannot know our future alignment,
556 // assume the worst.
557 if (i < nblocks - 1) {
558 Block* nb = C->cfg()->get_block(i + 1);
559 int max_loop_pad = nb->code_alignment()-relocInfo::addr_unit();
560 if (max_loop_pad > 0) {
561 assert(is_power_of_2(max_loop_pad+relocInfo::addr_unit()), "");
562 // Adjust last_call_adr and/or last_avoid_back_to_back_adr.
563 // If either is the last instruction in this block, bump by
564 // max_loop_pad in lock-step with blk_size, so sizing
565 // calculations in subsequent blocks still can conservatively
566 // detect that it may the last instruction in this block.
567 if (last_call_adr == blk_starts[i]+blk_size) {
568 last_call_adr += max_loop_pad;
569 }
570 if (last_avoid_back_to_back_adr == blk_starts[i]+blk_size) {
571 last_avoid_back_to_back_adr += max_loop_pad;
572 }
573 blk_size += max_loop_pad;
574 block_worst_case_pad[i + 1] = max_loop_pad;
575 }
576 }
577
578 // Save block size; update total method size
579 blk_starts[i+1] = blk_starts[i]+blk_size;
580 }
581
582 // Step two, replace eligible long jumps.
583 bool progress = true;
584 uint last_may_be_short_branch_adr = max_juint;
585 while (has_short_branch_candidate && progress) {
586 progress = false;
587 has_short_branch_candidate = false;
588 int adjust_block_start = 0;
589 for (uint i = 0; i < nblocks; i++) {
590 Block* block = C->cfg()->get_block(i);
591 int idx = jmp_nidx[i];
592 MachNode* mach = (idx == -1) ? NULL: block->get_node(idx)->as_Mach();
593 if (mach != NULL && mach->may_be_short_branch()) {
594 #ifdef ASSERT
595 assert(jmp_size[i] > 0 && mach->is_MachBranch(), "sanity");
596 int j;
597 // Find the branch; ignore trailing NOPs.
598 for (j = block->number_of_nodes()-1; j>=0; j--) {
599 Node* n = block->get_node(j);
600 if (!n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con)
601 break;
602 }
603 assert(j >= 0 && j == idx && block->get_node(j) == (Node*)mach, "sanity");
604 #endif
605 int br_size = jmp_size[i];
606 int br_offs = blk_starts[i] + jmp_offset[i];
607
608 // This requires the TRUE branch target be in succs[0]
609 uint bnum = block->non_connector_successor(0)->_pre_order;
610 int offset = blk_starts[bnum] - br_offs;
611 if (bnum > i) { // adjust following block's offset
612 offset -= adjust_block_start;
613 }
614
615 // This block can be a loop header, account for the padding
616 // in the previous block.
617 int block_padding = block_worst_case_pad[i];
618 assert(i == 0 || block_padding == 0 || br_offs >= block_padding, "Should have at least a padding on top");
619 // In the following code a nop could be inserted before
620 // the branch which will increase the backward distance.
621 bool needs_padding = ((uint)(br_offs - block_padding) == last_may_be_short_branch_adr);
622 assert(!needs_padding || jmp_offset[i] == 0, "padding only branches at the beginning of block");
623
624 if (needs_padding && offset <= 0)
625 offset -= nop_size;
626
627 if (C->matcher()->is_short_branch_offset(mach->rule(), br_size, offset)) {
628 // We've got a winner. Replace this branch.
629 MachNode* replacement = mach->as_MachBranch()->short_branch_version();
630
631 // Update the jmp_size.
632 int new_size = replacement->size(C->regalloc());
633 int diff = br_size - new_size;
634 assert(diff >= (int)nop_size, "short_branch size should be smaller");
635 // Conservatively take into account padding between
636 // avoid_back_to_back branches. Previous branch could be
637 // converted into avoid_back_to_back branch during next
638 // rounds.
639 if (needs_padding && replacement->avoid_back_to_back(MachNode::AVOID_BEFORE)) {
640 jmp_offset[i] += nop_size;
641 diff -= nop_size;
642 }
643 adjust_block_start += diff;
644 block->map_node(replacement, idx);
645 mach->subsume_by(replacement, C);
646 mach = replacement;
647 progress = true;
648
649 jmp_size[i] = new_size;
650 DEBUG_ONLY( jmp_target[i] = bnum; );
651 DEBUG_ONLY( jmp_rule[i] = mach->rule(); );
652 } else {
653 // The jump distance is not short, try again during next iteration.
654 has_short_branch_candidate = true;
655 }
656 } // (mach->may_be_short_branch())
657 if (mach != NULL && (mach->may_be_short_branch() ||
658 mach->avoid_back_to_back(MachNode::AVOID_AFTER))) {
659 last_may_be_short_branch_adr = blk_starts[i] + jmp_offset[i] + jmp_size[i];
660 }
661 blk_starts[i+1] -= adjust_block_start;
662 }
663 }
664
665 #ifdef ASSERT
666 for (uint i = 0; i < nblocks; i++) { // For all blocks
667 if (jmp_target[i] != 0) {
668 int br_size = jmp_size[i];
669 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_offset[i]);
670 if (!C->matcher()->is_short_branch_offset(jmp_rule[i], br_size, offset)) {
671 tty->print_cr("target (%d) - jmp_offset(%d) = offset (%d), jump_size(%d), jmp_block B%d, target_block B%d", blk_starts[jmp_target[i]], blk_starts[i] + jmp_offset[i], offset, br_size, i, jmp_target[i]);
672 }
673 assert(C->matcher()->is_short_branch_offset(jmp_rule[i], br_size, offset), "Displacement too large for short jmp");
674 }
675 }
676 #endif
677
678 // Step 3, compute the offsets of all blocks, will be done in fill_buffer()
679 // after ScheduleAndBundle().
680
681 // ------------------
682 // Compute size for code buffer
683 code_size = blk_starts[nblocks];
684
685 // Relocation records
686 reloc_size += 1; // Relo entry for exception handler
687
688 // Adjust reloc_size to number of record of relocation info
689 // Min is 2 bytes, max is probably 6 or 8, with a tax up to 25% for
690 // a relocation index.
691 // The CodeBuffer will expand the locs array if this estimate is too low.
692 reloc_size *= 10 / sizeof(relocInfo);
693
694 _buf_sizes._reloc = reloc_size;
695 _buf_sizes._code = code_size;
696 _buf_sizes._stub = stub_size;
697 }
698
699 //------------------------------FillLocArray-----------------------------------
700 // Create a bit of debug info and append it to the array. The mapping is from
701 // Java local or expression stack to constant, register or stack-slot. For
702 // doubles, insert 2 mappings and return 1 (to tell the caller that the next
703 // entry has been taken care of and caller should skip it).
704 static LocationValue *new_loc_value( PhaseRegAlloc *ra, OptoReg::Name regnum, Location::Type l_type ) {
705 // This should never have accepted Bad before
706 assert(OptoReg::is_valid(regnum), "location must be valid");
707 return (OptoReg::is_reg(regnum))
708 ? new LocationValue(Location::new_reg_loc(l_type, OptoReg::as_VMReg(regnum)) )
709 : new LocationValue(Location::new_stk_loc(l_type, ra->reg2offset(regnum)));
710 }
711
712
713 ObjectValue*
714 PhaseOutput::sv_for_node_id(GrowableArray<ScopeValue*> *objs, int id) {
715 for (int i = 0; i < objs->length(); i++) {
716 assert(objs->at(i)->is_object(), "corrupt object cache");
717 ObjectValue* sv = (ObjectValue*) objs->at(i);
718 if (sv->id() == id) {
719 return sv;
720 }
721 }
722 // Otherwise..
723 return NULL;
724 }
725
726 void PhaseOutput::set_sv_for_object_node(GrowableArray<ScopeValue*> *objs,
727 ObjectValue* sv ) {
728 assert(sv_for_node_id(objs, sv->id()) == NULL, "Precondition");
729 objs->append(sv);
730 }
731
732
733 void PhaseOutput::FillLocArray( int idx, MachSafePointNode* sfpt, Node *local,
734 GrowableArray<ScopeValue*> *array,
735 GrowableArray<ScopeValue*> *objs ) {
736 assert( local, "use _top instead of null" );
737 if (array->length() != idx) {
738 assert(array->length() == idx + 1, "Unexpected array count");
739 // Old functionality:
740 // return
741 // New functionality:
742 // Assert if the local is not top. In product mode let the new node
743 // override the old entry.
744 assert(local == C->top(), "LocArray collision");
745 if (local == C->top()) {
746 return;
747 }
748 array->pop();
749 }
750 const Type *t = local->bottom_type();
751
752 // Is it a safepoint scalar object node?
753 if (local->is_SafePointScalarObject()) {
754 SafePointScalarObjectNode* spobj = local->as_SafePointScalarObject();
755
756 ObjectValue* sv = sv_for_node_id(objs, spobj->_idx);
757 if (sv == NULL) {
758 ciKlass* cik = t->is_oopptr()->klass();
759 assert(cik->is_instance_klass() ||
760 cik->is_array_klass(), "Not supported allocation.");
761 sv = new ObjectValue(spobj->_idx,
762 new ConstantOopWriteValue(cik->java_mirror()->constant_encoding()));
763 set_sv_for_object_node(objs, sv);
764
765 uint first_ind = spobj->first_index(sfpt->jvms());
766 for (uint i = 0; i < spobj->n_fields(); i++) {
767 Node* fld_node = sfpt->in(first_ind+i);
768 (void)FillLocArray(sv->field_values()->length(), sfpt, fld_node, sv->field_values(), objs);
769 }
770 }
771 array->append(sv);
772 return;
773 }
774
775 // Grab the register number for the local
776 OptoReg::Name regnum = C->regalloc()->get_reg_first(local);
777 if( OptoReg::is_valid(regnum) ) {// Got a register/stack?
778 // Record the double as two float registers.
779 // The register mask for such a value always specifies two adjacent
780 // float registers, with the lower register number even.
781 // Normally, the allocation of high and low words to these registers
782 // is irrelevant, because nearly all operations on register pairs
783 // (e.g., StoreD) treat them as a single unit.
784 // Here, we assume in addition that the words in these two registers
785 // stored "naturally" (by operations like StoreD and double stores
786 // within the interpreter) such that the lower-numbered register
787 // is written to the lower memory address. This may seem like
788 // a machine dependency, but it is not--it is a requirement on
789 // the author of the <arch>.ad file to ensure that, for every
790 // even/odd double-register pair to which a double may be allocated,
791 // the word in the even single-register is stored to the first
792 // memory word. (Note that register numbers are completely
793 // arbitrary, and are not tied to any machine-level encodings.)
794 #ifdef _LP64
795 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon ) {
796 array->append(new ConstantIntValue((jint)0));
797 array->append(new_loc_value( C->regalloc(), regnum, Location::dbl ));
798 } else if ( t->base() == Type::Long ) {
799 array->append(new ConstantIntValue((jint)0));
800 array->append(new_loc_value( C->regalloc(), regnum, Location::lng ));
801 } else if ( t->base() == Type::RawPtr ) {
802 // jsr/ret return address which must be restored into a the full
803 // width 64-bit stack slot.
804 array->append(new_loc_value( C->regalloc(), regnum, Location::lng ));
805 }
806 #else //_LP64
807 #ifdef SPARC
808 if (t->base() == Type::Long && OptoReg::is_reg(regnum)) {
809 // For SPARC we have to swap high and low words for
810 // long values stored in a single-register (g0-g7).
811 array->append(new_loc_value( C->regalloc(), regnum , Location::normal ));
812 array->append(new_loc_value( C->regalloc(), OptoReg::add(regnum,1), Location::normal ));
813 } else
814 #endif //SPARC
815 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon || t->base() == Type::Long ) {
816 // Repack the double/long as two jints.
817 // The convention the interpreter uses is that the second local
818 // holds the first raw word of the native double representation.
819 // This is actually reasonable, since locals and stack arrays
820 // grow downwards in all implementations.
821 // (If, on some machine, the interpreter's Java locals or stack
822 // were to grow upwards, the embedded doubles would be word-swapped.)
823 array->append(new_loc_value( C->regalloc(), OptoReg::add(regnum,1), Location::normal ));
824 array->append(new_loc_value( C->regalloc(), regnum , Location::normal ));
825 }
826 #endif //_LP64
827 else if( (t->base() == Type::FloatBot || t->base() == Type::FloatCon) &&
828 OptoReg::is_reg(regnum) ) {
829 array->append(new_loc_value( C->regalloc(), regnum, Matcher::float_in_double()
830 ? Location::float_in_dbl : Location::normal ));
831 } else if( t->base() == Type::Int && OptoReg::is_reg(regnum) ) {
832 array->append(new_loc_value( C->regalloc(), regnum, Matcher::int_in_long
833 ? Location::int_in_long : Location::normal ));
834 } else if( t->base() == Type::NarrowOop ) {
835 array->append(new_loc_value( C->regalloc(), regnum, Location::narrowoop ));
836 } else {
837 array->append(new_loc_value( C->regalloc(), regnum, C->regalloc()->is_oop(local) ? Location::oop : Location::normal ));
838 }
839 return;
840 }
841
842 // No register. It must be constant data.
843 switch (t->base()) {
844 case Type::Half: // Second half of a double
845 ShouldNotReachHere(); // Caller should skip 2nd halves
846 break;
847 case Type::AnyPtr:
848 array->append(new ConstantOopWriteValue(NULL));
849 break;
850 case Type::AryPtr:
851 case Type::InstPtr: // fall through
852 array->append(new ConstantOopWriteValue(t->isa_oopptr()->const_oop()->constant_encoding()));
853 break;
854 case Type::NarrowOop:
855 if (t == TypeNarrowOop::NULL_PTR) {
856 array->append(new ConstantOopWriteValue(NULL));
857 } else {
858 array->append(new ConstantOopWriteValue(t->make_ptr()->isa_oopptr()->const_oop()->constant_encoding()));
859 }
860 break;
861 case Type::Int:
862 array->append(new ConstantIntValue(t->is_int()->get_con()));
863 break;
864 case Type::RawPtr:
865 // A return address (T_ADDRESS).
866 assert((intptr_t)t->is_ptr()->get_con() < (intptr_t)0x10000, "must be a valid BCI");
867 #ifdef _LP64
868 // Must be restored to the full-width 64-bit stack slot.
869 array->append(new ConstantLongValue(t->is_ptr()->get_con()));
870 #else
871 array->append(new ConstantIntValue(t->is_ptr()->get_con()));
872 #endif
873 break;
874 case Type::FloatCon: {
875 float f = t->is_float_constant()->getf();
876 array->append(new ConstantIntValue(jint_cast(f)));
877 break;
878 }
879 case Type::DoubleCon: {
880 jdouble d = t->is_double_constant()->getd();
881 #ifdef _LP64
882 array->append(new ConstantIntValue((jint)0));
883 array->append(new ConstantDoubleValue(d));
884 #else
885 // Repack the double as two jints.
886 // The convention the interpreter uses is that the second local
887 // holds the first raw word of the native double representation.
888 // This is actually reasonable, since locals and stack arrays
889 // grow downwards in all implementations.
890 // (If, on some machine, the interpreter's Java locals or stack
891 // were to grow upwards, the embedded doubles would be word-swapped.)
892 jlong_accessor acc;
893 acc.long_value = jlong_cast(d);
894 array->append(new ConstantIntValue(acc.words[1]));
895 array->append(new ConstantIntValue(acc.words[0]));
896 #endif
897 break;
898 }
899 case Type::Long: {
900 jlong d = t->is_long()->get_con();
901 #ifdef _LP64
902 array->append(new ConstantIntValue((jint)0));
903 array->append(new ConstantLongValue(d));
904 #else
905 // Repack the long as two jints.
906 // The convention the interpreter uses is that the second local
907 // holds the first raw word of the native double representation.
908 // This is actually reasonable, since locals and stack arrays
909 // grow downwards in all implementations.
910 // (If, on some machine, the interpreter's Java locals or stack
911 // were to grow upwards, the embedded doubles would be word-swapped.)
912 jlong_accessor acc;
913 acc.long_value = d;
914 array->append(new ConstantIntValue(acc.words[1]));
915 array->append(new ConstantIntValue(acc.words[0]));
916 #endif
917 break;
918 }
919 case Type::Top: // Add an illegal value here
920 array->append(new LocationValue(Location()));
921 break;
922 default:
923 ShouldNotReachHere();
924 break;
925 }
926 }
927
928 // Determine if this node starts a bundle
929 bool PhaseOutput::starts_bundle(const Node *n) const {
930 return (_node_bundling_limit > n->_idx &&
931 _node_bundling_base[n->_idx].starts_bundle());
932 }
933
934 //--------------------------Process_OopMap_Node--------------------------------
935 void PhaseOutput::Process_OopMap_Node(MachNode *mach, int current_offset) {
936 // Handle special safepoint nodes for synchronization
937 MachSafePointNode *sfn = mach->as_MachSafePoint();
938 MachCallNode *mcall;
939
940 int safepoint_pc_offset = current_offset;
941 bool is_method_handle_invoke = false;
942 bool return_oop = false;
943
944 // Add the safepoint in the DebugInfoRecorder
945 if( !mach->is_MachCall() ) {
946 mcall = NULL;
947 C->debug_info()->add_safepoint(safepoint_pc_offset, sfn->_oop_map);
948 } else {
949 mcall = mach->as_MachCall();
950
951 // Is the call a MethodHandle call?
952 if (mcall->is_MachCallJava()) {
953 if (mcall->as_MachCallJava()->_method_handle_invoke) {
954 assert(C->has_method_handle_invokes(), "must have been set during call generation");
955 is_method_handle_invoke = true;
956 }
957 }
958
959 // Check if a call returns an object.
960 if (mcall->returns_pointer()) {
961 return_oop = true;
962 }
963 safepoint_pc_offset += mcall->ret_addr_offset();
964 C->debug_info()->add_safepoint(safepoint_pc_offset, mcall->_oop_map);
965 }
966
967 // Loop over the JVMState list to add scope information
968 // Do not skip safepoints with a NULL method, they need monitor info
969 JVMState* youngest_jvms = sfn->jvms();
970 int max_depth = youngest_jvms->depth();
971
972 // Allocate the object pool for scalar-replaced objects -- the map from
973 // small-integer keys (which can be recorded in the local and ostack
974 // arrays) to descriptions of the object state.
975 GrowableArray<ScopeValue*> *objs = new GrowableArray<ScopeValue*>();
976
977 // Visit scopes from oldest to youngest.
978 for (int depth = 1; depth <= max_depth; depth++) {
979 JVMState* jvms = youngest_jvms->of_depth(depth);
980 int idx;
981 ciMethod* method = jvms->has_method() ? jvms->method() : NULL;
982 // Safepoints that do not have method() set only provide oop-map and monitor info
983 // to support GC; these do not support deoptimization.
984 int num_locs = (method == NULL) ? 0 : jvms->loc_size();
985 int num_exps = (method == NULL) ? 0 : jvms->stk_size();
986 int num_mon = jvms->nof_monitors();
987 assert(method == NULL || jvms->bci() < 0 || num_locs == method->max_locals(),
988 "JVMS local count must match that of the method");
989
990 // Add Local and Expression Stack Information
991
992 // Insert locals into the locarray
993 GrowableArray<ScopeValue*> *locarray = new GrowableArray<ScopeValue*>(num_locs);
994 for( idx = 0; idx < num_locs; idx++ ) {
995 FillLocArray( idx, sfn, sfn->local(jvms, idx), locarray, objs );
996 }
997
998 // Insert expression stack entries into the exparray
999 GrowableArray<ScopeValue*> *exparray = new GrowableArray<ScopeValue*>(num_exps);
1000 for( idx = 0; idx < num_exps; idx++ ) {
1001 FillLocArray( idx, sfn, sfn->stack(jvms, idx), exparray, objs );
1002 }
1003
1004 // Add in mappings of the monitors
1005 assert( !method ||
1006 !method->is_synchronized() ||
1007 method->is_native() ||
1008 num_mon > 0 ||
1009 !GenerateSynchronizationCode,
1010 "monitors must always exist for synchronized methods");
1011
1012 // Build the growable array of ScopeValues for exp stack
1013 GrowableArray<MonitorValue*> *monarray = new GrowableArray<MonitorValue*>(num_mon);
1014
1015 // Loop over monitors and insert into array
1016 for (idx = 0; idx < num_mon; idx++) {
1017 // Grab the node that defines this monitor
1018 Node* box_node = sfn->monitor_box(jvms, idx);
1019 Node* obj_node = sfn->monitor_obj(jvms, idx);
1020
1021 // Create ScopeValue for object
1022 ScopeValue *scval = NULL;
1023
1024 if (obj_node->is_SafePointScalarObject()) {
1025 SafePointScalarObjectNode* spobj = obj_node->as_SafePointScalarObject();
1026 scval = PhaseOutput::sv_for_node_id(objs, spobj->_idx);
1027 if (scval == NULL) {
1028 const Type *t = spobj->bottom_type();
1029 ciKlass* cik = t->is_oopptr()->klass();
1030 assert(cik->is_instance_klass() ||
1031 cik->is_array_klass(), "Not supported allocation.");
1032 ObjectValue* sv = new ObjectValue(spobj->_idx,
1033 new ConstantOopWriteValue(cik->java_mirror()->constant_encoding()));
1034 PhaseOutput::set_sv_for_object_node(objs, sv);
1035
1036 uint first_ind = spobj->first_index(youngest_jvms);
1037 for (uint i = 0; i < spobj->n_fields(); i++) {
1038 Node* fld_node = sfn->in(first_ind+i);
1039 (void)FillLocArray(sv->field_values()->length(), sfn, fld_node, sv->field_values(), objs);
1040 }
1041 scval = sv;
1042 }
1043 } else if (!obj_node->is_Con()) {
1044 OptoReg::Name obj_reg = C->regalloc()->get_reg_first(obj_node);
1045 if( obj_node->bottom_type()->base() == Type::NarrowOop ) {
1046 scval = new_loc_value( C->regalloc(), obj_reg, Location::narrowoop );
1047 } else {
1048 scval = new_loc_value( C->regalloc(), obj_reg, Location::oop );
1049 }
1050 } else {
1051 const TypePtr *tp = obj_node->get_ptr_type();
1052 scval = new ConstantOopWriteValue(tp->is_oopptr()->const_oop()->constant_encoding());
1053 }
1054
1055 OptoReg::Name box_reg = BoxLockNode::reg(box_node);
1056 Location basic_lock = Location::new_stk_loc(Location::normal,C->regalloc()->reg2offset(box_reg));
1057 bool eliminated = (box_node->is_BoxLock() && box_node->as_BoxLock()->is_eliminated());
1058 monarray->append(new MonitorValue(scval, basic_lock, eliminated));
1059 }
1060
1061 // We dump the object pool first, since deoptimization reads it in first.
1062 C->debug_info()->dump_object_pool(objs);
1063
1064 // Build first class objects to pass to scope
1065 DebugToken *locvals = C->debug_info()->create_scope_values(locarray);
1066 DebugToken *expvals = C->debug_info()->create_scope_values(exparray);
1067 DebugToken *monvals = C->debug_info()->create_monitor_values(monarray);
1068
1069 // Make method available for all Safepoints
1070 ciMethod* scope_method = method ? method : C->method();
1071 // Describe the scope here
1072 assert(jvms->bci() >= InvocationEntryBci && jvms->bci() <= 0x10000, "must be a valid or entry BCI");
1073 assert(!jvms->should_reexecute() || depth == max_depth, "reexecute allowed only for the youngest");
1074 // Now we can describe the scope.
1075 methodHandle null_mh;
1076 bool rethrow_exception = false;
1077 C->debug_info()->describe_scope(safepoint_pc_offset, null_mh, scope_method, jvms->bci(), jvms->should_reexecute(), rethrow_exception, is_method_handle_invoke, return_oop, locvals, expvals, monvals);
1078 } // End jvms loop
1079
1080 // Mark the end of the scope set.
1081 C->debug_info()->end_safepoint(safepoint_pc_offset);
1082 }
1083
1084
1085
1086 // A simplified version of Process_OopMap_Node, to handle non-safepoints.
1087 class NonSafepointEmitter {
1088 Compile* C;
1089 JVMState* _pending_jvms;
1090 int _pending_offset;
1091
1092 void emit_non_safepoint();
1093
1094 public:
1095 NonSafepointEmitter(Compile* compile) {
1096 this->C = compile;
1097 _pending_jvms = NULL;
1098 _pending_offset = 0;
1099 }
1100
1101 void observe_instruction(Node* n, int pc_offset) {
1102 if (!C->debug_info()->recording_non_safepoints()) return;
1103
1104 Node_Notes* nn = C->node_notes_at(n->_idx);
1105 if (nn == NULL || nn->jvms() == NULL) return;
1106 if (_pending_jvms != NULL &&
1107 _pending_jvms->same_calls_as(nn->jvms())) {
1108 // Repeated JVMS? Stretch it up here.
1109 _pending_offset = pc_offset;
1110 } else {
1111 if (_pending_jvms != NULL &&
1112 _pending_offset < pc_offset) {
1113 emit_non_safepoint();
1114 }
1115 _pending_jvms = NULL;
1116 if (pc_offset > C->debug_info()->last_pc_offset()) {
1117 // This is the only way _pending_jvms can become non-NULL:
1118 _pending_jvms = nn->jvms();
1119 _pending_offset = pc_offset;
1120 }
1121 }
1122 }
1123
1124 // Stay out of the way of real safepoints:
1125 void observe_safepoint(JVMState* jvms, int pc_offset) {
1126 if (_pending_jvms != NULL &&
1127 !_pending_jvms->same_calls_as(jvms) &&
1128 _pending_offset < pc_offset) {
1129 emit_non_safepoint();
1130 }
1131 _pending_jvms = NULL;
1132 }
1133
1134 void flush_at_end() {
1135 if (_pending_jvms != NULL) {
1136 emit_non_safepoint();
1137 }
1138 _pending_jvms = NULL;
1139 }
1140 };
1141
1142 void NonSafepointEmitter::emit_non_safepoint() {
1143 JVMState* youngest_jvms = _pending_jvms;
1144 int pc_offset = _pending_offset;
1145
1146 // Clear it now:
1147 _pending_jvms = NULL;
1148
1149 DebugInformationRecorder* debug_info = C->debug_info();
1150 assert(debug_info->recording_non_safepoints(), "sanity");
1151
1152 debug_info->add_non_safepoint(pc_offset);
1153 int max_depth = youngest_jvms->depth();
1154
1155 // Visit scopes from oldest to youngest.
1156 for (int depth = 1; depth <= max_depth; depth++) {
1157 JVMState* jvms = youngest_jvms->of_depth(depth);
1158 ciMethod* method = jvms->has_method() ? jvms->method() : NULL;
1159 assert(!jvms->should_reexecute() || depth==max_depth, "reexecute allowed only for the youngest");
1160 methodHandle null_mh;
1161 debug_info->describe_scope(pc_offset, null_mh, method, jvms->bci(), jvms->should_reexecute());
1162 }
1163
1164 // Mark the end of the scope set.
1165 debug_info->end_non_safepoint(pc_offset);
1166 }
1167
1168 //------------------------------init_buffer------------------------------------
1169 void PhaseOutput::estimate_buffer_size(int& const_req) {
1170
1171 // Set the initially allocated size
1172 const_req = initial_const_capacity;
1173
1174 // The extra spacing after the code is necessary on some platforms.
1175 // Sometimes we need to patch in a jump after the last instruction,
1176 // if the nmethod has been deoptimized. (See 4932387, 4894843.)
1177
1178 // Compute the byte offset where we can store the deopt pc.
1179 if (C->fixed_slots() != 0) {
1180 _orig_pc_slot_offset_in_bytes = C->regalloc()->reg2offset(OptoReg::stack2reg(_orig_pc_slot));
1181 }
1182
1183 // Compute prolog code size
1184 _method_size = 0;
1185 _frame_slots = OptoReg::reg2stack(C->matcher()->_old_SP) + C->regalloc()->_framesize;
1186 #if defined(IA64) && !defined(AIX)
1187 if (save_argument_registers()) {
1188 // 4815101: this is a stub with implicit and unknown precision fp args.
1189 // The usual spill mechanism can only generate stfd's in this case, which
1190 // doesn't work if the fp reg to spill contains a single-precision denorm.
1191 // Instead, we hack around the normal spill mechanism using stfspill's and
1192 // ldffill's in the MachProlog and MachEpilog emit methods. We allocate
1193 // space here for the fp arg regs (f8-f15) we're going to thusly spill.
1194 //
1195 // If we ever implement 16-byte 'registers' == stack slots, we can
1196 // get rid of this hack and have SpillCopy generate stfspill/ldffill
1197 // instead of stfd/stfs/ldfd/ldfs.
1198 _frame_slots += 8*(16/BytesPerInt);
1199 }
1200 #endif
1201 assert(_frame_slots >= 0 && _frame_slots < 1000000, "sanity check");
1202
1203 if (C->has_mach_constant_base_node()) {
1204 uint add_size = 0;
1205 // Fill the constant table.
1206 // Note: This must happen before shorten_branches.
1207 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) {
1208 Block* b = C->cfg()->get_block(i);
1209
1210 for (uint j = 0; j < b->number_of_nodes(); j++) {
1211 Node* n = b->get_node(j);
1212
1213 // If the node is a MachConstantNode evaluate the constant
1214 // value section.
1215 if (n->is_MachConstant()) {
1216 MachConstantNode* machcon = n->as_MachConstant();
1217 machcon->eval_constant(C);
1218 } else if (n->is_Mach()) {
1219 // On Power there are more nodes that issue constants.
1220 add_size += (n->as_Mach()->ins_num_consts() * 8);
1221 }
1222 }
1223 }
1224
1225 // Calculate the offsets of the constants and the size of the
1226 // constant table (including the padding to the next section).
1227 constant_table().calculate_offsets_and_size();
1228 const_req = constant_table().size() + add_size;
1229 }
1230
1231 // Initialize the space for the BufferBlob used to find and verify
1232 // instruction size in MachNode::emit_size()
1233 init_scratch_buffer_blob(const_req);
1234 }
1235
1236 CodeBuffer* PhaseOutput::init_buffer() {
1237 int stub_req = _buf_sizes._stub;
1238 int code_req = _buf_sizes._code;
1239 int const_req = _buf_sizes._const;
1240
1241 int pad_req = NativeCall::instruction_size;
1242
1243 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1244 stub_req += bs->estimate_stub_size();
1245
1246 // nmethod and CodeBuffer count stubs & constants as part of method's code.
1247 // class HandlerImpl is platform-specific and defined in the *.ad files.
1248 int exception_handler_req = HandlerImpl::size_exception_handler() + MAX_stubs_size; // add marginal slop for handler
1249 int deopt_handler_req = HandlerImpl::size_deopt_handler() + MAX_stubs_size; // add marginal slop for handler
1250 stub_req += MAX_stubs_size; // ensure per-stub margin
1251 code_req += MAX_inst_size; // ensure per-instruction margin
1252
1253 if (StressCodeBuffers)
1254 code_req = const_req = stub_req = exception_handler_req = deopt_handler_req = 0x10; // force expansion
1255
1256 int total_req =
1257 const_req +
1258 code_req +
1259 pad_req +
1260 stub_req +
1261 exception_handler_req +
1262 deopt_handler_req; // deopt handler
1263
1264 if (C->has_method_handle_invokes())
1265 total_req += deopt_handler_req; // deopt MH handler
1266
1267 CodeBuffer* cb = code_buffer();
1268 cb->initialize(total_req, _buf_sizes._reloc);
1269
1270 // Have we run out of code space?
1271 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) {
1272 C->record_failure("CodeCache is full");
1273 return NULL;
1274 }
1275 // Configure the code buffer.
1276 cb->initialize_consts_size(const_req);
1277 cb->initialize_stubs_size(stub_req);
1278 cb->initialize_oop_recorder(C->env()->oop_recorder());
1279
1280 // fill in the nop array for bundling computations
1281 MachNode *_nop_list[Bundle::_nop_count];
1282 Bundle::initialize_nops(_nop_list);
1283
1284 return cb;
1285 }
1286
1287 //------------------------------fill_buffer------------------------------------
1288 void PhaseOutput::fill_buffer(CodeBuffer* cb, uint* blk_starts) {
1289 // blk_starts[] contains offsets calculated during short branches processing,
1290 // offsets should not be increased during following steps.
1291
1292 // Compute the size of first NumberOfLoopInstrToAlign instructions at head
1293 // of a loop. It is used to determine the padding for loop alignment.
1294 compute_loop_first_inst_sizes();
1295
1296 // Create oopmap set.
1297 _oop_map_set = new OopMapSet();
1298
1299 // !!!!! This preserves old handling of oopmaps for now
1300 C->debug_info()->set_oopmaps(_oop_map_set);
1301
1302 uint nblocks = C->cfg()->number_of_blocks();
1303 // Count and start of implicit null check instructions
1304 uint inct_cnt = 0;
1305 uint *inct_starts = NEW_RESOURCE_ARRAY(uint, nblocks+1);
1306
1307 // Count and start of calls
1308 uint *call_returns = NEW_RESOURCE_ARRAY(uint, nblocks+1);
1309
1310 uint return_offset = 0;
1311 int nop_size = (new MachNopNode())->size(C->regalloc());
1312
1313 int previous_offset = 0;
1314 int current_offset = 0;
1315 int last_call_offset = -1;
1316 int last_avoid_back_to_back_offset = -1;
1317 #ifdef ASSERT
1318 uint* jmp_target = NEW_RESOURCE_ARRAY(uint,nblocks);
1319 uint* jmp_offset = NEW_RESOURCE_ARRAY(uint,nblocks);
1320 uint* jmp_size = NEW_RESOURCE_ARRAY(uint,nblocks);
1321 uint* jmp_rule = NEW_RESOURCE_ARRAY(uint,nblocks);
1322 #endif
1323
1324 // Create an array of unused labels, one for each basic block, if printing is enabled
1325 #if defined(SUPPORT_OPTO_ASSEMBLY)
1326 int *node_offsets = NULL;
1327 uint node_offset_limit = C->unique();
1328
1329 if (C->print_assembly()) {
1330 node_offsets = NEW_RESOURCE_ARRAY(int, node_offset_limit);
1331 }
1332 if (node_offsets != NULL) {
1333 // We need to initialize. Unused array elements may contain garbage and mess up PrintOptoAssembly.
1334 memset(node_offsets, 0, node_offset_limit*sizeof(int));
1335 }
1336 #endif
1337
1338 NonSafepointEmitter non_safepoints(C); // emit non-safepoints lazily
1339
1340 // Emit the constant table.
1341 if (C->has_mach_constant_base_node()) {
1342 constant_table().emit(*cb);
1343 }
1344
1345 // Create an array of labels, one for each basic block
1346 Label *blk_labels = NEW_RESOURCE_ARRAY(Label, nblocks+1);
1347 for (uint i=0; i <= nblocks; i++) {
1348 blk_labels[i].init();
1349 }
1350
1351 // ------------------
1352 // Now fill in the code buffer
1353 Node *delay_slot = NULL;
1354
1355 for (uint i = 0; i < nblocks; i++) {
1356 Block* block = C->cfg()->get_block(i);
1357 _block = block;
1358 Node* head = block->head();
1359
1360 // If this block needs to start aligned (i.e, can be reached other
1361 // than by falling-thru from the previous block), then force the
1362 // start of a new bundle.
1363 if (Pipeline::requires_bundling() && starts_bundle(head)) {
1364 cb->flush_bundle(true);
1365 }
1366
1367 #ifdef ASSERT
1368 if (!block->is_connector()) {
1369 stringStream st;
1370 block->dump_head(C->cfg(), &st);
1371 MacroAssembler(cb).block_comment(st.as_string());
1372 }
1373 jmp_target[i] = 0;
1374 jmp_offset[i] = 0;
1375 jmp_size[i] = 0;
1376 jmp_rule[i] = 0;
1377 #endif
1378 int blk_offset = current_offset;
1379
1380 // Define the label at the beginning of the basic block
1381 MacroAssembler(cb).bind(blk_labels[block->_pre_order]);
1382
1383 uint last_inst = block->number_of_nodes();
1384
1385 // Emit block normally, except for last instruction.
1386 // Emit means "dump code bits into code buffer".
1387 for (uint j = 0; j<last_inst; j++) {
1388 _index = j;
1389
1390 // Get the node
1391 Node* n = block->get_node(j);
1392
1393 // See if delay slots are supported
1394 if (valid_bundle_info(n) && node_bundling(n)->used_in_unconditional_delay()) {
1395 assert(delay_slot == NULL, "no use of delay slot node");
1396 assert(n->size(C->regalloc()) == Pipeline::instr_unit_size(), "delay slot instruction wrong size");
1397
1398 delay_slot = n;
1399 continue;
1400 }
1401
1402 // If this starts a new instruction group, then flush the current one
1403 // (but allow split bundles)
1404 if (Pipeline::requires_bundling() && starts_bundle(n))
1405 cb->flush_bundle(false);
1406
1407 // Special handling for SafePoint/Call Nodes
1408 bool is_mcall = false;
1409 if (n->is_Mach()) {
1410 MachNode *mach = n->as_Mach();
1411 is_mcall = n->is_MachCall();
1412 bool is_sfn = n->is_MachSafePoint();
1413
1414 // If this requires all previous instructions be flushed, then do so
1415 if (is_sfn || is_mcall || mach->alignment_required() != 1) {
1416 cb->flush_bundle(true);
1417 current_offset = cb->insts_size();
1418 }
1419
1420 // A padding may be needed again since a previous instruction
1421 // could be moved to delay slot.
1422
1423 // align the instruction if necessary
1424 int padding = mach->compute_padding(current_offset);
1425 // Make sure safepoint node for polling is distinct from a call's
1426 // return by adding a nop if needed.
1427 if (is_sfn && !is_mcall && padding == 0 && current_offset == last_call_offset) {
1428 padding = nop_size;
1429 }
1430 if (padding == 0 && mach->avoid_back_to_back(MachNode::AVOID_BEFORE) &&
1431 current_offset == last_avoid_back_to_back_offset) {
1432 // Avoid back to back some instructions.
1433 padding = nop_size;
1434 }
1435
1436 if (padding > 0) {
1437 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size");
1438 int nops_cnt = padding / nop_size;
1439 MachNode *nop = new MachNopNode(nops_cnt);
1440 block->insert_node(nop, j++);
1441 last_inst++;
1442 C->cfg()->map_node_to_block(nop, block);
1443 // Ensure enough space.
1444 cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size);
1445 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) {
1446 C->record_failure("CodeCache is full");
1447 return;
1448 }
1449 nop->emit(*cb, C->regalloc());
1450 cb->flush_bundle(true);
1451 current_offset = cb->insts_size();
1452 }
1453
1454 // Remember the start of the last call in a basic block
1455 if (is_mcall) {
1456 MachCallNode *mcall = mach->as_MachCall();
1457
1458 // This destination address is NOT PC-relative
1459 mcall->method_set((intptr_t)mcall->entry_point());
1460
1461 // Save the return address
1462 call_returns[block->_pre_order] = current_offset + mcall->ret_addr_offset();
1463
1464 if (mcall->is_MachCallLeaf()) {
1465 is_mcall = false;
1466 is_sfn = false;
1467 }
1468 }
1469
1470 // sfn will be valid whenever mcall is valid now because of inheritance
1471 if (is_sfn || is_mcall) {
1472
1473 // Handle special safepoint nodes for synchronization
1474 if (!is_mcall) {
1475 MachSafePointNode *sfn = mach->as_MachSafePoint();
1476 // !!!!! Stubs only need an oopmap right now, so bail out
1477 if (sfn->jvms()->method() == NULL) {
1478 // Write the oopmap directly to the code blob??!!
1479 continue;
1480 }
1481 } // End synchronization
1482
1483 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(),
1484 current_offset);
1485 Process_OopMap_Node(mach, current_offset);
1486 } // End if safepoint
1487
1488 // If this is a null check, then add the start of the previous instruction to the list
1489 else if( mach->is_MachNullCheck() ) {
1490 inct_starts[inct_cnt++] = previous_offset;
1491 }
1492
1493 // If this is a branch, then fill in the label with the target BB's label
1494 else if (mach->is_MachBranch()) {
1495 // This requires the TRUE branch target be in succs[0]
1496 uint block_num = block->non_connector_successor(0)->_pre_order;
1497
1498 // Try to replace long branch if delay slot is not used,
1499 // it is mostly for back branches since forward branch's
1500 // distance is not updated yet.
1501 bool delay_slot_is_used = valid_bundle_info(n) &&
1502 C->output()->node_bundling(n)->use_unconditional_delay();
1503 if (!delay_slot_is_used && mach->may_be_short_branch()) {
1504 assert(delay_slot == NULL, "not expecting delay slot node");
1505 int br_size = n->size(C->regalloc());
1506 int offset = blk_starts[block_num] - current_offset;
1507 if (block_num >= i) {
1508 // Current and following block's offset are not
1509 // finalized yet, adjust distance by the difference
1510 // between calculated and final offsets of current block.
1511 offset -= (blk_starts[i] - blk_offset);
1512 }
1513 // In the following code a nop could be inserted before
1514 // the branch which will increase the backward distance.
1515 bool needs_padding = (current_offset == last_avoid_back_to_back_offset);
1516 if (needs_padding && offset <= 0)
1517 offset -= nop_size;
1518
1519 if (C->matcher()->is_short_branch_offset(mach->rule(), br_size, offset)) {
1520 // We've got a winner. Replace this branch.
1521 MachNode* replacement = mach->as_MachBranch()->short_branch_version();
1522
1523 // Update the jmp_size.
1524 int new_size = replacement->size(C->regalloc());
1525 assert((br_size - new_size) >= (int)nop_size, "short_branch size should be smaller");
1526 // Insert padding between avoid_back_to_back branches.
1527 if (needs_padding && replacement->avoid_back_to_back(MachNode::AVOID_BEFORE)) {
1528 MachNode *nop = new MachNopNode();
1529 block->insert_node(nop, j++);
1530 C->cfg()->map_node_to_block(nop, block);
1531 last_inst++;
1532 nop->emit(*cb, C->regalloc());
1533 cb->flush_bundle(true);
1534 current_offset = cb->insts_size();
1535 }
1536 #ifdef ASSERT
1537 jmp_target[i] = block_num;
1538 jmp_offset[i] = current_offset - blk_offset;
1539 jmp_size[i] = new_size;
1540 jmp_rule[i] = mach->rule();
1541 #endif
1542 block->map_node(replacement, j);
1543 mach->subsume_by(replacement, C);
1544 n = replacement;
1545 mach = replacement;
1546 }
1547 }
1548 mach->as_MachBranch()->label_set( &blk_labels[block_num], block_num );
1549 } else if (mach->ideal_Opcode() == Op_Jump) {
1550 for (uint h = 0; h < block->_num_succs; h++) {
1551 Block* succs_block = block->_succs[h];
1552 for (uint j = 1; j < succs_block->num_preds(); j++) {
1553 Node* jpn = succs_block->pred(j);
1554 if (jpn->is_JumpProj() && jpn->in(0) == mach) {
1555 uint block_num = succs_block->non_connector()->_pre_order;
1556 Label *blkLabel = &blk_labels[block_num];
1557 mach->add_case_label(jpn->as_JumpProj()->proj_no(), blkLabel);
1558 }
1559 }
1560 }
1561 }
1562 #ifdef ASSERT
1563 // Check that oop-store precedes the card-mark
1564 else if (mach->ideal_Opcode() == Op_StoreCM) {
1565 uint storeCM_idx = j;
1566 int count = 0;
1567 for (uint prec = mach->req(); prec < mach->len(); prec++) {
1568 Node *oop_store = mach->in(prec); // Precedence edge
1569 if (oop_store == NULL) continue;
1570 count++;
1571 uint i4;
1572 for (i4 = 0; i4 < last_inst; ++i4) {
1573 if (block->get_node(i4) == oop_store) {
1574 break;
1575 }
1576 }
1577 // Note: This test can provide a false failure if other precedence
1578 // edges have been added to the storeCMNode.
1579 assert(i4 == last_inst || i4 < storeCM_idx, "CM card-mark executes before oop-store");
1580 }
1581 assert(count > 0, "storeCM expects at least one precedence edge");
1582 }
1583 #endif
1584 else if (!n->is_Proj()) {
1585 // Remember the beginning of the previous instruction, in case
1586 // it's followed by a flag-kill and a null-check. Happens on
1587 // Intel all the time, with add-to-memory kind of opcodes.
1588 previous_offset = current_offset;
1589 }
1590
1591 // Not an else-if!
1592 // If this is a trap based cmp then add its offset to the list.
1593 if (mach->is_TrapBasedCheckNode()) {
1594 inct_starts[inct_cnt++] = current_offset;
1595 }
1596 }
1597
1598 // Verify that there is sufficient space remaining
1599 cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size);
1600 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) {
1601 C->record_failure("CodeCache is full");
1602 return;
1603 }
1604
1605 // Save the offset for the listing
1606 #if defined(SUPPORT_OPTO_ASSEMBLY)
1607 if ((node_offsets != NULL) && (n->_idx < node_offset_limit)) {
1608 node_offsets[n->_idx] = cb->insts_size();
1609 }
1610 #endif
1611
1612 // "Normal" instruction case
1613 DEBUG_ONLY( uint instr_offset = cb->insts_size(); )
1614 n->emit(*cb, C->regalloc());
1615 current_offset = cb->insts_size();
1616
1617 // Above we only verified that there is enough space in the instruction section.
1618 // However, the instruction may emit stubs that cause code buffer expansion.
1619 // Bail out here if expansion failed due to a lack of code cache space.
1620 if (C->failing()) {
1621 return;
1622 }
1623
1624 #ifdef ASSERT
1625 if (n->size(C->regalloc()) < (current_offset-instr_offset)) {
1626 n->dump();
1627 assert(false, "wrong size of mach node");
1628 }
1629 #endif
1630 non_safepoints.observe_instruction(n, current_offset);
1631
1632 // mcall is last "call" that can be a safepoint
1633 // record it so we can see if a poll will directly follow it
1634 // in which case we'll need a pad to make the PcDesc sites unique
1635 // see 5010568. This can be slightly inaccurate but conservative
1636 // in the case that return address is not actually at current_offset.
1637 // This is a small price to pay.
1638
1639 if (is_mcall) {
1640 last_call_offset = current_offset;
1641 }
1642
1643 if (n->is_Mach() && n->as_Mach()->avoid_back_to_back(MachNode::AVOID_AFTER)) {
1644 // Avoid back to back some instructions.
1645 last_avoid_back_to_back_offset = current_offset;
1646 }
1647
1648 // See if this instruction has a delay slot
1649 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
1650 guarantee(delay_slot != NULL, "expecting delay slot node");
1651
1652 // Back up 1 instruction
1653 cb->set_insts_end(cb->insts_end() - Pipeline::instr_unit_size());
1654
1655 // Save the offset for the listing
1656 #if defined(SUPPORT_OPTO_ASSEMBLY)
1657 if ((node_offsets != NULL) && (delay_slot->_idx < node_offset_limit)) {
1658 node_offsets[delay_slot->_idx] = cb->insts_size();
1659 }
1660 #endif
1661
1662 // Support a SafePoint in the delay slot
1663 if (delay_slot->is_MachSafePoint()) {
1664 MachNode *mach = delay_slot->as_Mach();
1665 // !!!!! Stubs only need an oopmap right now, so bail out
1666 if (!mach->is_MachCall() && mach->as_MachSafePoint()->jvms()->method() == NULL) {
1667 // Write the oopmap directly to the code blob??!!
1668 delay_slot = NULL;
1669 continue;
1670 }
1671
1672 int adjusted_offset = current_offset - Pipeline::instr_unit_size();
1673 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(),
1674 adjusted_offset);
1675 // Generate an OopMap entry
1676 Process_OopMap_Node(mach, adjusted_offset);
1677 }
1678
1679 // Insert the delay slot instruction
1680 delay_slot->emit(*cb, C->regalloc());
1681
1682 // Don't reuse it
1683 delay_slot = NULL;
1684 }
1685
1686 } // End for all instructions in block
1687
1688 // If the next block is the top of a loop, pad this block out to align
1689 // the loop top a little. Helps prevent pipe stalls at loop back branches.
1690 if (i < nblocks-1) {
1691 Block *nb = C->cfg()->get_block(i + 1);
1692 int padding = nb->alignment_padding(current_offset);
1693 if( padding > 0 ) {
1694 MachNode *nop = new MachNopNode(padding / nop_size);
1695 block->insert_node(nop, block->number_of_nodes());
1696 C->cfg()->map_node_to_block(nop, block);
1697 nop->emit(*cb, C->regalloc());
1698 current_offset = cb->insts_size();
1699 }
1700 }
1701 // Verify that the distance for generated before forward
1702 // short branches is still valid.
1703 guarantee((int)(blk_starts[i+1] - blk_starts[i]) >= (current_offset - blk_offset), "shouldn't increase block size");
1704
1705 // Save new block start offset
1706 blk_starts[i] = blk_offset;
1707 } // End of for all blocks
1708 blk_starts[nblocks] = current_offset;
1709
1710 non_safepoints.flush_at_end();
1711
1712 // Offset too large?
1713 if (C->failing()) return;
1714
1715 // Define a pseudo-label at the end of the code
1716 MacroAssembler(cb).bind( blk_labels[nblocks] );
1717
1718 // Compute the size of the first block
1719 _first_block_size = blk_labels[1].loc_pos() - blk_labels[0].loc_pos();
1720
1721 #ifdef ASSERT
1722 for (uint i = 0; i < nblocks; i++) { // For all blocks
1723 if (jmp_target[i] != 0) {
1724 int br_size = jmp_size[i];
1725 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_offset[i]);
1726 if (!C->matcher()->is_short_branch_offset(jmp_rule[i], br_size, offset)) {
1727 tty->print_cr("target (%d) - jmp_offset(%d) = offset (%d), jump_size(%d), jmp_block B%d, target_block B%d", blk_starts[jmp_target[i]], blk_starts[i] + jmp_offset[i], offset, br_size, i, jmp_target[i]);
1728 assert(false, "Displacement too large for short jmp");
1729 }
1730 }
1731 }
1732 #endif
1733
1734 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1735 bs->emit_stubs(*cb);
1736 if (C->failing()) return;
1737
1738 #ifndef PRODUCT
1739 // Information on the size of the method, without the extraneous code
1740 Scheduling::increment_method_size(cb->insts_size());
1741 #endif
1742
1743 // ------------------
1744 // Fill in exception table entries.
1745 FillExceptionTables(inct_cnt, call_returns, inct_starts, blk_labels);
1746
1747 // Only java methods have exception handlers and deopt handlers
1748 // class HandlerImpl is platform-specific and defined in the *.ad files.
1749 if (C->method()) {
1750 // Emit the exception handler code.
1751 _code_offsets.set_value(CodeOffsets::Exceptions, HandlerImpl::emit_exception_handler(*cb));
1752 if (C->failing()) {
1753 return; // CodeBuffer::expand failed
1754 }
1755 // Emit the deopt handler code.
1756 _code_offsets.set_value(CodeOffsets::Deopt, HandlerImpl::emit_deopt_handler(*cb));
1757
1758 // Emit the MethodHandle deopt handler code (if required).
1759 if (C->has_method_handle_invokes() && !C->failing()) {
1760 // We can use the same code as for the normal deopt handler, we
1761 // just need a different entry point address.
1762 _code_offsets.set_value(CodeOffsets::DeoptMH, HandlerImpl::emit_deopt_handler(*cb));
1763 }
1764 }
1765
1766 // One last check for failed CodeBuffer::expand:
1767 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) {
1768 C->record_failure("CodeCache is full");
1769 return;
1770 }
1771
1772 #if defined(SUPPORT_ABSTRACT_ASSEMBLY) || defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_OPTO_ASSEMBLY)
1773 if (C->print_assembly()) {
1774 tty->cr();
1775 tty->print_cr("============================= C2-compiled nmethod ==============================");
1776 }
1777 #endif
1778
1779 #if defined(SUPPORT_OPTO_ASSEMBLY)
1780 // Dump the assembly code, including basic-block numbers
1781 if (C->print_assembly()) {
1782 ttyLocker ttyl; // keep the following output all in one block
1783 if (!VMThread::should_terminate()) { // test this under the tty lock
1784 // This output goes directly to the tty, not the compiler log.
1785 // To enable tools to match it up with the compilation activity,
1786 // be sure to tag this tty output with the compile ID.
1787 if (xtty != NULL) {
1788 xtty->head("opto_assembly compile_id='%d'%s", C->compile_id(),
1789 C->is_osr_compilation() ? " compile_kind='osr'" :
1790 "");
1791 }
1792 if (C->method() != NULL) {
1793 tty->print_cr("----------------------- MetaData before Compile_id = %d ------------------------", C->compile_id());
1794 C->method()->print_metadata();
1795 } else if (C->stub_name() != NULL) {
1796 tty->print_cr("----------------------------- RuntimeStub %s -------------------------------", C->stub_name());
1797 }
1798 tty->cr();
1799 tty->print_cr("------------------------ OptoAssembly for Compile_id = %d -----------------------", C->compile_id());
1800 dump_asm(node_offsets, node_offset_limit);
1801 tty->print_cr("--------------------------------------------------------------------------------");
1802 if (xtty != NULL) {
1803 // print_metadata and dump_asm above may safepoint which makes us loose the ttylock.
1804 // Retake lock too make sure the end tag is coherent, and that xmlStream->pop_tag is done
1805 // thread safe
1806 ttyLocker ttyl2;
1807 xtty->tail("opto_assembly");
1808 }
1809 }
1810 }
1811 #endif
1812 }
1813
1814 void PhaseOutput::FillExceptionTables(uint cnt, uint *call_returns, uint *inct_starts, Label *blk_labels) {
1815 _inc_table.set_size(cnt);
1816
1817 uint inct_cnt = 0;
1818 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) {
1819 Block* block = C->cfg()->get_block(i);
1820 Node *n = NULL;
1821 int j;
1822
1823 // Find the branch; ignore trailing NOPs.
1824 for (j = block->number_of_nodes() - 1; j >= 0; j--) {
1825 n = block->get_node(j);
1826 if (!n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con) {
1827 break;
1828 }
1829 }
1830
1831 // If we didn't find anything, continue
1832 if (j < 0) {
1833 continue;
1834 }
1835
1836 // Compute ExceptionHandlerTable subtable entry and add it
1837 // (skip empty blocks)
1838 if (n->is_Catch()) {
1839
1840 // Get the offset of the return from the call
1841 uint call_return = call_returns[block->_pre_order];
1842 #ifdef ASSERT
1843 assert( call_return > 0, "no call seen for this basic block" );
1844 while (block->get_node(--j)->is_MachProj()) ;
1845 assert(block->get_node(j)->is_MachCall(), "CatchProj must follow call");
1846 #endif
1847 // last instruction is a CatchNode, find it's CatchProjNodes
1848 int nof_succs = block->_num_succs;
1849 // allocate space
1850 GrowableArray<intptr_t> handler_bcis(nof_succs);
1851 GrowableArray<intptr_t> handler_pcos(nof_succs);
1852 // iterate through all successors
1853 for (int j = 0; j < nof_succs; j++) {
1854 Block* s = block->_succs[j];
1855 bool found_p = false;
1856 for (uint k = 1; k < s->num_preds(); k++) {
1857 Node* pk = s->pred(k);
1858 if (pk->is_CatchProj() && pk->in(0) == n) {
1859 const CatchProjNode* p = pk->as_CatchProj();
1860 found_p = true;
1861 // add the corresponding handler bci & pco information
1862 if (p->_con != CatchProjNode::fall_through_index) {
1863 // p leads to an exception handler (and is not fall through)
1864 assert(s == C->cfg()->get_block(s->_pre_order), "bad numbering");
1865 // no duplicates, please
1866 if (!handler_bcis.contains(p->handler_bci())) {
1867 uint block_num = s->non_connector()->_pre_order;
1868 handler_bcis.append(p->handler_bci());
1869 handler_pcos.append(blk_labels[block_num].loc_pos());
1870 }
1871 }
1872 }
1873 }
1874 assert(found_p, "no matching predecessor found");
1875 // Note: Due to empty block removal, one block may have
1876 // several CatchProj inputs, from the same Catch.
1877 }
1878
1879 // Set the offset of the return from the call
1880 assert(handler_bcis.find(-1) != -1, "must have default handler");
1881 _handler_table.add_subtable(call_return, &handler_bcis, NULL, &handler_pcos);
1882 continue;
1883 }
1884
1885 // Handle implicit null exception table updates
1886 if (n->is_MachNullCheck()) {
1887 uint block_num = block->non_connector_successor(0)->_pre_order;
1888 _inc_table.append(inct_starts[inct_cnt++], blk_labels[block_num].loc_pos());
1889 continue;
1890 }
1891 // Handle implicit exception table updates: trap instructions.
1892 if (n->is_Mach() && n->as_Mach()->is_TrapBasedCheckNode()) {
1893 uint block_num = block->non_connector_successor(0)->_pre_order;
1894 _inc_table.append(inct_starts[inct_cnt++], blk_labels[block_num].loc_pos());
1895 continue;
1896 }
1897 } // End of for all blocks fill in exception table entries
1898 }
1899
1900 // Static Variables
1901 #ifndef PRODUCT
1902 uint Scheduling::_total_nop_size = 0;
1903 uint Scheduling::_total_method_size = 0;
1904 uint Scheduling::_total_branches = 0;
1905 uint Scheduling::_total_unconditional_delays = 0;
1906 uint Scheduling::_total_instructions_per_bundle[Pipeline::_max_instrs_per_cycle+1];
1907 #endif
1908
1909 // Initializer for class Scheduling
1910
1911 Scheduling::Scheduling(Arena *arena, Compile &compile)
1912 : _arena(arena),
1913 _cfg(compile.cfg()),
1914 _regalloc(compile.regalloc()),
1915 _scheduled(arena),
1916 _available(arena),
1917 _reg_node(arena),
1918 _pinch_free_list(arena),
1919 _next_node(NULL),
1920 _bundle_instr_count(0),
1921 _bundle_cycle_number(0),
1922 _bundle_use(0, 0, resource_count, &_bundle_use_elements[0])
1923 #ifndef PRODUCT
1924 , _branches(0)
1925 , _unconditional_delays(0)
1926 #endif
1927 {
1928 // Create a MachNopNode
1929 _nop = new MachNopNode();
1930
1931 // Now that the nops are in the array, save the count
1932 // (but allow entries for the nops)
1933 _node_bundling_limit = compile.unique();
1934 uint node_max = _regalloc->node_regs_max_index();
1935
1936 compile.output()->set_node_bundling_limit(_node_bundling_limit);
1937
1938 // This one is persistent within the Compile class
1939 _node_bundling_base = NEW_ARENA_ARRAY(compile.comp_arena(), Bundle, node_max);
1940
1941 // Allocate space for fixed-size arrays
1942 _node_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max);
1943 _uses = NEW_ARENA_ARRAY(arena, short, node_max);
1944 _current_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max);
1945
1946 // Clear the arrays
1947 for (uint i = 0; i < node_max; i++) {
1948 ::new (&_node_bundling_base[i]) Bundle();
1949 }
1950 memset(_node_latency, 0, node_max * sizeof(unsigned short));
1951 memset(_uses, 0, node_max * sizeof(short));
1952 memset(_current_latency, 0, node_max * sizeof(unsigned short));
1953
1954 // Clear the bundling information
1955 memcpy(_bundle_use_elements, Pipeline_Use::elaborated_elements, sizeof(Pipeline_Use::elaborated_elements));
1956
1957 // Get the last node
1958 Block* block = _cfg->get_block(_cfg->number_of_blocks() - 1);
1959
1960 _next_node = block->get_node(block->number_of_nodes() - 1);
1961 }
1962
1963 #ifndef PRODUCT
1964 // Scheduling destructor
1965 Scheduling::~Scheduling() {
1966 _total_branches += _branches;
1967 _total_unconditional_delays += _unconditional_delays;
1968 }
1969 #endif
1970
1971 // Step ahead "i" cycles
1972 void Scheduling::step(uint i) {
1973
1974 Bundle *bundle = node_bundling(_next_node);
1975 bundle->set_starts_bundle();
1976
1977 // Update the bundle record, but leave the flags information alone
1978 if (_bundle_instr_count > 0) {
1979 bundle->set_instr_count(_bundle_instr_count);
1980 bundle->set_resources_used(_bundle_use.resourcesUsed());
1981 }
1982
1983 // Update the state information
1984 _bundle_instr_count = 0;
1985 _bundle_cycle_number += i;
1986 _bundle_use.step(i);
1987 }
1988
1989 void Scheduling::step_and_clear() {
1990 Bundle *bundle = node_bundling(_next_node);
1991 bundle->set_starts_bundle();
1992
1993 // Update the bundle record
1994 if (_bundle_instr_count > 0) {
1995 bundle->set_instr_count(_bundle_instr_count);
1996 bundle->set_resources_used(_bundle_use.resourcesUsed());
1997
1998 _bundle_cycle_number += 1;
1999 }
2000
2001 // Clear the bundling information
2002 _bundle_instr_count = 0;
2003 _bundle_use.reset();
2004
2005 memcpy(_bundle_use_elements,
2006 Pipeline_Use::elaborated_elements,
2007 sizeof(Pipeline_Use::elaborated_elements));
2008 }
2009
2010 // Perform instruction scheduling and bundling over the sequence of
2011 // instructions in backwards order.
2012 void PhaseOutput::ScheduleAndBundle() {
2013
2014 // Don't optimize this if it isn't a method
2015 if (!C->method())
2016 return;
2017
2018 // Don't optimize this if scheduling is disabled
2019 if (!C->do_scheduling())
2020 return;
2021
2022 // Scheduling code works only with pairs (16 bytes) maximum.
2023 if (C->max_vector_size() > 16)
2024 return;
2025
2026 Compile::TracePhase tp("isched", &timers[_t_instrSched]);
2027
2028 // Create a data structure for all the scheduling information
2029 Scheduling scheduling(Thread::current()->resource_area(), *C);
2030
2031 // Walk backwards over each basic block, computing the needed alignment
2032 // Walk over all the basic blocks
2033 scheduling.DoScheduling();
2034
2035 #ifndef PRODUCT
2036 if (C->trace_opto_output()) {
2037 tty->print("\n---- After ScheduleAndBundle ----\n");
2038 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) {
2039 tty->print("\nBB#%03d:\n", i);
2040 Block* block = C->cfg()->get_block(i);
2041 for (uint j = 0; j < block->number_of_nodes(); j++) {
2042 Node* n = block->get_node(j);
2043 OptoReg::Name reg = C->regalloc()->get_reg_first(n);
2044 tty->print(" %-6s ", reg >= 0 && reg < REG_COUNT ? Matcher::regName[reg] : "");
2045 n->dump();
2046 }
2047 }
2048 }
2049 #endif
2050 }
2051
2052 // Compute the latency of all the instructions. This is fairly simple,
2053 // because we already have a legal ordering. Walk over the instructions
2054 // from first to last, and compute the latency of the instruction based
2055 // on the latency of the preceding instruction(s).
2056 void Scheduling::ComputeLocalLatenciesForward(const Block *bb) {
2057 #ifndef PRODUCT
2058 if (_cfg->C->trace_opto_output())
2059 tty->print("# -> ComputeLocalLatenciesForward\n");
2060 #endif
2061
2062 // Walk over all the schedulable instructions
2063 for( uint j=_bb_start; j < _bb_end; j++ ) {
2064
2065 // This is a kludge, forcing all latency calculations to start at 1.
2066 // Used to allow latency 0 to force an instruction to the beginning
2067 // of the bb
2068 uint latency = 1;
2069 Node *use = bb->get_node(j);
2070 uint nlen = use->len();
2071
2072 // Walk over all the inputs
2073 for ( uint k=0; k < nlen; k++ ) {
2074 Node *def = use->in(k);
2075 if (!def)
2076 continue;
2077
2078 uint l = _node_latency[def->_idx] + use->latency(k);
2079 if (latency < l)
2080 latency = l;
2081 }
2082
2083 _node_latency[use->_idx] = latency;
2084
2085 #ifndef PRODUCT
2086 if (_cfg->C->trace_opto_output()) {
2087 tty->print("# latency %4d: ", latency);
2088 use->dump();
2089 }
2090 #endif
2091 }
2092
2093 #ifndef PRODUCT
2094 if (_cfg->C->trace_opto_output())
2095 tty->print("# <- ComputeLocalLatenciesForward\n");
2096 #endif
2097
2098 } // end ComputeLocalLatenciesForward
2099
2100 // See if this node fits into the present instruction bundle
2101 bool Scheduling::NodeFitsInBundle(Node *n) {
2102 uint n_idx = n->_idx;
2103
2104 // If this is the unconditional delay instruction, then it fits
2105 if (n == _unconditional_delay_slot) {
2106 #ifndef PRODUCT
2107 if (_cfg->C->trace_opto_output())
2108 tty->print("# NodeFitsInBundle [%4d]: TRUE; is in unconditional delay slot\n", n->_idx);
2109 #endif
2110 return (true);
2111 }
2112
2113 // If the node cannot be scheduled this cycle, skip it
2114 if (_current_latency[n_idx] > _bundle_cycle_number) {
2115 #ifndef PRODUCT
2116 if (_cfg->C->trace_opto_output())
2117 tty->print("# NodeFitsInBundle [%4d]: FALSE; latency %4d > %d\n",
2118 n->_idx, _current_latency[n_idx], _bundle_cycle_number);
2119 #endif
2120 return (false);
2121 }
2122
2123 const Pipeline *node_pipeline = n->pipeline();
2124
2125 uint instruction_count = node_pipeline->instructionCount();
2126 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0)
2127 instruction_count = 0;
2128 else if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot)
2129 instruction_count++;
2130
2131 if (_bundle_instr_count + instruction_count > Pipeline::_max_instrs_per_cycle) {
2132 #ifndef PRODUCT
2133 if (_cfg->C->trace_opto_output())
2134 tty->print("# NodeFitsInBundle [%4d]: FALSE; too many instructions: %d > %d\n",
2135 n->_idx, _bundle_instr_count + instruction_count, Pipeline::_max_instrs_per_cycle);
2136 #endif
2137 return (false);
2138 }
2139
2140 // Don't allow non-machine nodes to be handled this way
2141 if (!n->is_Mach() && instruction_count == 0)
2142 return (false);
2143
2144 // See if there is any overlap
2145 uint delay = _bundle_use.full_latency(0, node_pipeline->resourceUse());
2146
2147 if (delay > 0) {
2148 #ifndef PRODUCT
2149 if (_cfg->C->trace_opto_output())
2150 tty->print("# NodeFitsInBundle [%4d]: FALSE; functional units overlap\n", n_idx);
2151 #endif
2152 return false;
2153 }
2154
2155 #ifndef PRODUCT
2156 if (_cfg->C->trace_opto_output())
2157 tty->print("# NodeFitsInBundle [%4d]: TRUE\n", n_idx);
2158 #endif
2159
2160 return true;
2161 }
2162
2163 Node * Scheduling::ChooseNodeToBundle() {
2164 uint siz = _available.size();
2165
2166 if (siz == 0) {
2167
2168 #ifndef PRODUCT
2169 if (_cfg->C->trace_opto_output())
2170 tty->print("# ChooseNodeToBundle: NULL\n");
2171 #endif
2172 return (NULL);
2173 }
2174
2175 // Fast path, if only 1 instruction in the bundle
2176 if (siz == 1) {
2177 #ifndef PRODUCT
2178 if (_cfg->C->trace_opto_output()) {
2179 tty->print("# ChooseNodeToBundle (only 1): ");
2180 _available[0]->dump();
2181 }
2182 #endif
2183 return (_available[0]);
2184 }
2185
2186 // Don't bother, if the bundle is already full
2187 if (_bundle_instr_count < Pipeline::_max_instrs_per_cycle) {
2188 for ( uint i = 0; i < siz; i++ ) {
2189 Node *n = _available[i];
2190
2191 // Skip projections, we'll handle them another way
2192 if (n->is_Proj())
2193 continue;
2194
2195 // This presupposed that instructions are inserted into the
2196 // available list in a legality order; i.e. instructions that
2197 // must be inserted first are at the head of the list
2198 if (NodeFitsInBundle(n)) {
2199 #ifndef PRODUCT
2200 if (_cfg->C->trace_opto_output()) {
2201 tty->print("# ChooseNodeToBundle: ");
2202 n->dump();
2203 }
2204 #endif
2205 return (n);
2206 }
2207 }
2208 }
2209
2210 // Nothing fits in this bundle, choose the highest priority
2211 #ifndef PRODUCT
2212 if (_cfg->C->trace_opto_output()) {
2213 tty->print("# ChooseNodeToBundle: ");
2214 _available[0]->dump();
2215 }
2216 #endif
2217
2218 return _available[0];
2219 }
2220
2221 void Scheduling::AddNodeToAvailableList(Node *n) {
2222 assert( !n->is_Proj(), "projections never directly made available" );
2223 #ifndef PRODUCT
2224 if (_cfg->C->trace_opto_output()) {
2225 tty->print("# AddNodeToAvailableList: ");
2226 n->dump();
2227 }
2228 #endif
2229
2230 int latency = _current_latency[n->_idx];
2231
2232 // Insert in latency order (insertion sort)
2233 uint i;
2234 for ( i=0; i < _available.size(); i++ )
2235 if (_current_latency[_available[i]->_idx] > latency)
2236 break;
2237
2238 // Special Check for compares following branches
2239 if( n->is_Mach() && _scheduled.size() > 0 ) {
2240 int op = n->as_Mach()->ideal_Opcode();
2241 Node *last = _scheduled[0];
2242 if( last->is_MachIf() && last->in(1) == n &&
2243 ( op == Op_CmpI ||
2244 op == Op_CmpU ||
2245 op == Op_CmpUL ||
2246 op == Op_CmpP ||
2247 op == Op_CmpF ||
2248 op == Op_CmpD ||
2249 op == Op_CmpL ) ) {
2250
2251 // Recalculate position, moving to front of same latency
2252 for ( i=0 ; i < _available.size(); i++ )
2253 if (_current_latency[_available[i]->_idx] >= latency)
2254 break;
2255 }
2256 }
2257
2258 // Insert the node in the available list
2259 _available.insert(i, n);
2260
2261 #ifndef PRODUCT
2262 if (_cfg->C->trace_opto_output())
2263 dump_available();
2264 #endif
2265 }
2266
2267 void Scheduling::DecrementUseCounts(Node *n, const Block *bb) {
2268 for ( uint i=0; i < n->len(); i++ ) {
2269 Node *def = n->in(i);
2270 if (!def) continue;
2271 if( def->is_Proj() ) // If this is a machine projection, then
2272 def = def->in(0); // propagate usage thru to the base instruction
2273
2274 if(_cfg->get_block_for_node(def) != bb) { // Ignore if not block-local
2275 continue;
2276 }
2277
2278 // Compute the latency
2279 uint l = _bundle_cycle_number + n->latency(i);
2280 if (_current_latency[def->_idx] < l)
2281 _current_latency[def->_idx] = l;
2282
2283 // If this does not have uses then schedule it
2284 if ((--_uses[def->_idx]) == 0)
2285 AddNodeToAvailableList(def);
2286 }
2287 }
2288
2289 void Scheduling::AddNodeToBundle(Node *n, const Block *bb) {
2290 #ifndef PRODUCT
2291 if (_cfg->C->trace_opto_output()) {
2292 tty->print("# AddNodeToBundle: ");
2293 n->dump();
2294 }
2295 #endif
2296
2297 // Remove this from the available list
2298 uint i;
2299 for (i = 0; i < _available.size(); i++)
2300 if (_available[i] == n)
2301 break;
2302 assert(i < _available.size(), "entry in _available list not found");
2303 _available.remove(i);
2304
2305 // See if this fits in the current bundle
2306 const Pipeline *node_pipeline = n->pipeline();
2307 const Pipeline_Use& node_usage = node_pipeline->resourceUse();
2308
2309 // Check for instructions to be placed in the delay slot. We
2310 // do this before we actually schedule the current instruction,
2311 // because the delay slot follows the current instruction.
2312 if (Pipeline::_branch_has_delay_slot &&
2313 node_pipeline->hasBranchDelay() &&
2314 !_unconditional_delay_slot) {
2315
2316 uint siz = _available.size();
2317
2318 // Conditional branches can support an instruction that
2319 // is unconditionally executed and not dependent by the
2320 // branch, OR a conditionally executed instruction if
2321 // the branch is taken. In practice, this means that
2322 // the first instruction at the branch target is
2323 // copied to the delay slot, and the branch goes to
2324 // the instruction after that at the branch target
2325 if ( n->is_MachBranch() ) {
2326
2327 assert( !n->is_MachNullCheck(), "should not look for delay slot for Null Check" );
2328 assert( !n->is_Catch(), "should not look for delay slot for Catch" );
2329
2330 #ifndef PRODUCT
2331 _branches++;
2332 #endif
2333
2334 // At least 1 instruction is on the available list
2335 // that is not dependent on the branch
2336 for (uint i = 0; i < siz; i++) {
2337 Node *d = _available[i];
2338 const Pipeline *avail_pipeline = d->pipeline();
2339
2340 // Don't allow safepoints in the branch shadow, that will
2341 // cause a number of difficulties
2342 if ( avail_pipeline->instructionCount() == 1 &&
2343 !avail_pipeline->hasMultipleBundles() &&
2344 !avail_pipeline->hasBranchDelay() &&
2345 Pipeline::instr_has_unit_size() &&
2346 d->size(_regalloc) == Pipeline::instr_unit_size() &&
2347 NodeFitsInBundle(d) &&
2348 !node_bundling(d)->used_in_delay()) {
2349
2350 if (d->is_Mach() && !d->is_MachSafePoint()) {
2351 // A node that fits in the delay slot was found, so we need to
2352 // set the appropriate bits in the bundle pipeline information so
2353 // that it correctly indicates resource usage. Later, when we
2354 // attempt to add this instruction to the bundle, we will skip
2355 // setting the resource usage.
2356 _unconditional_delay_slot = d;
2357 node_bundling(n)->set_use_unconditional_delay();
2358 node_bundling(d)->set_used_in_unconditional_delay();
2359 _bundle_use.add_usage(avail_pipeline->resourceUse());
2360 _current_latency[d->_idx] = _bundle_cycle_number;
2361 _next_node = d;
2362 ++_bundle_instr_count;
2363 #ifndef PRODUCT
2364 _unconditional_delays++;
2365 #endif
2366 break;
2367 }
2368 }
2369 }
2370 }
2371
2372 // No delay slot, add a nop to the usage
2373 if (!_unconditional_delay_slot) {
2374 // See if adding an instruction in the delay slot will overflow
2375 // the bundle.
2376 if (!NodeFitsInBundle(_nop)) {
2377 #ifndef PRODUCT
2378 if (_cfg->C->trace_opto_output())
2379 tty->print("# *** STEP(1 instruction for delay slot) ***\n");
2380 #endif
2381 step(1);
2382 }
2383
2384 _bundle_use.add_usage(_nop->pipeline()->resourceUse());
2385 _next_node = _nop;
2386 ++_bundle_instr_count;
2387 }
2388
2389 // See if the instruction in the delay slot requires a
2390 // step of the bundles
2391 if (!NodeFitsInBundle(n)) {
2392 #ifndef PRODUCT
2393 if (_cfg->C->trace_opto_output())
2394 tty->print("# *** STEP(branch won't fit) ***\n");
2395 #endif
2396 // Update the state information
2397 _bundle_instr_count = 0;
2398 _bundle_cycle_number += 1;
2399 _bundle_use.step(1);
2400 }
2401 }
2402
2403 // Get the number of instructions
2404 uint instruction_count = node_pipeline->instructionCount();
2405 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0)
2406 instruction_count = 0;
2407
2408 // Compute the latency information
2409 uint delay = 0;
2410
2411 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) {
2412 int relative_latency = _current_latency[n->_idx] - _bundle_cycle_number;
2413 if (relative_latency < 0)
2414 relative_latency = 0;
2415
2416 delay = _bundle_use.full_latency(relative_latency, node_usage);
2417
2418 // Does not fit in this bundle, start a new one
2419 if (delay > 0) {
2420 step(delay);
2421
2422 #ifndef PRODUCT
2423 if (_cfg->C->trace_opto_output())
2424 tty->print("# *** STEP(%d) ***\n", delay);
2425 #endif
2426 }
2427 }
2428
2429 // If this was placed in the delay slot, ignore it
2430 if (n != _unconditional_delay_slot) {
2431
2432 if (delay == 0) {
2433 if (node_pipeline->hasMultipleBundles()) {
2434 #ifndef PRODUCT
2435 if (_cfg->C->trace_opto_output())
2436 tty->print("# *** STEP(multiple instructions) ***\n");
2437 #endif
2438 step(1);
2439 }
2440
2441 else if (instruction_count + _bundle_instr_count > Pipeline::_max_instrs_per_cycle) {
2442 #ifndef PRODUCT
2443 if (_cfg->C->trace_opto_output())
2444 tty->print("# *** STEP(%d >= %d instructions) ***\n",
2445 instruction_count + _bundle_instr_count,
2446 Pipeline::_max_instrs_per_cycle);
2447 #endif
2448 step(1);
2449 }
2450 }
2451
2452 if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot)
2453 _bundle_instr_count++;
2454
2455 // Set the node's latency
2456 _current_latency[n->_idx] = _bundle_cycle_number;
2457
2458 // Now merge the functional unit information
2459 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode())
2460 _bundle_use.add_usage(node_usage);
2461
2462 // Increment the number of instructions in this bundle
2463 _bundle_instr_count += instruction_count;
2464
2465 // Remember this node for later
2466 if (n->is_Mach())
2467 _next_node = n;
2468 }
2469
2470 // It's possible to have a BoxLock in the graph and in the _bbs mapping but
2471 // not in the bb->_nodes array. This happens for debug-info-only BoxLocks.
2472 // 'Schedule' them (basically ignore in the schedule) but do not insert them
2473 // into the block. All other scheduled nodes get put in the schedule here.
2474 int op = n->Opcode();
2475 if( (op == Op_Node && n->req() == 0) || // anti-dependence node OR
2476 (op != Op_Node && // Not an unused antidepedence node and
2477 // not an unallocated boxlock
2478 (OptoReg::is_valid(_regalloc->get_reg_first(n)) || op != Op_BoxLock)) ) {
2479
2480 // Push any trailing projections
2481 if( bb->get_node(bb->number_of_nodes()-1) != n ) {
2482 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2483 Node *foi = n->fast_out(i);
2484 if( foi->is_Proj() )
2485 _scheduled.push(foi);
2486 }
2487 }
2488
2489 // Put the instruction in the schedule list
2490 _scheduled.push(n);
2491 }
2492
2493 #ifndef PRODUCT
2494 if (_cfg->C->trace_opto_output())
2495 dump_available();
2496 #endif
2497
2498 // Walk all the definitions, decrementing use counts, and
2499 // if a definition has a 0 use count, place it in the available list.
2500 DecrementUseCounts(n,bb);
2501 }
2502
2503 // This method sets the use count within a basic block. We will ignore all
2504 // uses outside the current basic block. As we are doing a backwards walk,
2505 // any node we reach that has a use count of 0 may be scheduled. This also
2506 // avoids the problem of cyclic references from phi nodes, as long as phi
2507 // nodes are at the front of the basic block. This method also initializes
2508 // the available list to the set of instructions that have no uses within this
2509 // basic block.
2510 void Scheduling::ComputeUseCount(const Block *bb) {
2511 #ifndef PRODUCT
2512 if (_cfg->C->trace_opto_output())
2513 tty->print("# -> ComputeUseCount\n");
2514 #endif
2515
2516 // Clear the list of available and scheduled instructions, just in case
2517 _available.clear();
2518 _scheduled.clear();
2519
2520 // No delay slot specified
2521 _unconditional_delay_slot = NULL;
2522
2523 #ifdef ASSERT
2524 for( uint i=0; i < bb->number_of_nodes(); i++ )
2525 assert( _uses[bb->get_node(i)->_idx] == 0, "_use array not clean" );
2526 #endif
2527
2528 // Force the _uses count to never go to zero for unscheduable pieces
2529 // of the block
2530 for( uint k = 0; k < _bb_start; k++ )
2531 _uses[bb->get_node(k)->_idx] = 1;
2532 for( uint l = _bb_end; l < bb->number_of_nodes(); l++ )
2533 _uses[bb->get_node(l)->_idx] = 1;
2534
2535 // Iterate backwards over the instructions in the block. Don't count the
2536 // branch projections at end or the block header instructions.
2537 for( uint j = _bb_end-1; j >= _bb_start; j-- ) {
2538 Node *n = bb->get_node(j);
2539 if( n->is_Proj() ) continue; // Projections handled another way
2540
2541 // Account for all uses
2542 for ( uint k = 0; k < n->len(); k++ ) {
2543 Node *inp = n->in(k);
2544 if (!inp) continue;
2545 assert(inp != n, "no cycles allowed" );
2546 if (_cfg->get_block_for_node(inp) == bb) { // Block-local use?
2547 if (inp->is_Proj()) { // Skip through Proj's
2548 inp = inp->in(0);
2549 }
2550 ++_uses[inp->_idx]; // Count 1 block-local use
2551 }
2552 }
2553
2554 // If this instruction has a 0 use count, then it is available
2555 if (!_uses[n->_idx]) {
2556 _current_latency[n->_idx] = _bundle_cycle_number;
2557 AddNodeToAvailableList(n);
2558 }
2559
2560 #ifndef PRODUCT
2561 if (_cfg->C->trace_opto_output()) {
2562 tty->print("# uses: %3d: ", _uses[n->_idx]);
2563 n->dump();
2564 }
2565 #endif
2566 }
2567
2568 #ifndef PRODUCT
2569 if (_cfg->C->trace_opto_output())
2570 tty->print("# <- ComputeUseCount\n");
2571 #endif
2572 }
2573
2574 // This routine performs scheduling on each basic block in reverse order,
2575 // using instruction latencies and taking into account function unit
2576 // availability.
2577 void Scheduling::DoScheduling() {
2578 #ifndef PRODUCT
2579 if (_cfg->C->trace_opto_output())
2580 tty->print("# -> DoScheduling\n");
2581 #endif
2582
2583 Block *succ_bb = NULL;
2584 Block *bb;
2585 Compile* C = Compile::current();
2586
2587 // Walk over all the basic blocks in reverse order
2588 for (int i = _cfg->number_of_blocks() - 1; i >= 0; succ_bb = bb, i--) {
2589 bb = _cfg->get_block(i);
2590
2591 #ifndef PRODUCT
2592 if (_cfg->C->trace_opto_output()) {
2593 tty->print("# Schedule BB#%03d (initial)\n", i);
2594 for (uint j = 0; j < bb->number_of_nodes(); j++) {
2595 bb->get_node(j)->dump();
2596 }
2597 }
2598 #endif
2599
2600 // On the head node, skip processing
2601 if (bb == _cfg->get_root_block()) {
2602 continue;
2603 }
2604
2605 // Skip empty, connector blocks
2606 if (bb->is_connector())
2607 continue;
2608
2609 // If the following block is not the sole successor of
2610 // this one, then reset the pipeline information
2611 if (bb->_num_succs != 1 || bb->non_connector_successor(0) != succ_bb) {
2612 #ifndef PRODUCT
2613 if (_cfg->C->trace_opto_output()) {
2614 tty->print("*** bundle start of next BB, node %d, for %d instructions\n",
2615 _next_node->_idx, _bundle_instr_count);
2616 }
2617 #endif
2618 step_and_clear();
2619 }
2620
2621 // Leave untouched the starting instruction, any Phis, a CreateEx node
2622 // or Top. bb->get_node(_bb_start) is the first schedulable instruction.
2623 _bb_end = bb->number_of_nodes()-1;
2624 for( _bb_start=1; _bb_start <= _bb_end; _bb_start++ ) {
2625 Node *n = bb->get_node(_bb_start);
2626 // Things not matched, like Phinodes and ProjNodes don't get scheduled.
2627 // Also, MachIdealNodes do not get scheduled
2628 if( !n->is_Mach() ) continue; // Skip non-machine nodes
2629 MachNode *mach = n->as_Mach();
2630 int iop = mach->ideal_Opcode();
2631 if( iop == Op_CreateEx ) continue; // CreateEx is pinned
2632 if( iop == Op_Con ) continue; // Do not schedule Top
2633 if( iop == Op_Node && // Do not schedule PhiNodes, ProjNodes
2634 mach->pipeline() == MachNode::pipeline_class() &&
2635 !n->is_SpillCopy() && !n->is_MachMerge() ) // Breakpoints, Prolog, etc
2636 continue;
2637 break; // Funny loop structure to be sure...
2638 }
2639 // Compute last "interesting" instruction in block - last instruction we
2640 // might schedule. _bb_end points just after last schedulable inst. We
2641 // normally schedule conditional branches (despite them being forced last
2642 // in the block), because they have delay slots we can fill. Calls all
2643 // have their delay slots filled in the template expansions, so we don't
2644 // bother scheduling them.
2645 Node *last = bb->get_node(_bb_end);
2646 // Ignore trailing NOPs.
2647 while (_bb_end > 0 && last->is_Mach() &&
2648 last->as_Mach()->ideal_Opcode() == Op_Con) {
2649 last = bb->get_node(--_bb_end);
2650 }
2651 assert(!last->is_Mach() || last->as_Mach()->ideal_Opcode() != Op_Con, "");
2652 if( last->is_Catch() ||
2653 (last->is_Mach() && last->as_Mach()->ideal_Opcode() == Op_Halt) ) {
2654 // There might be a prior call. Skip it.
2655 while (_bb_start < _bb_end && bb->get_node(--_bb_end)->is_MachProj());
2656 } else if( last->is_MachNullCheck() ) {
2657 // Backup so the last null-checked memory instruction is
2658 // outside the schedulable range. Skip over the nullcheck,
2659 // projection, and the memory nodes.
2660 Node *mem = last->in(1);
2661 do {
2662 _bb_end--;
2663 } while (mem != bb->get_node(_bb_end));
2664 } else {
2665 // Set _bb_end to point after last schedulable inst.
2666 _bb_end++;
2667 }
2668
2669 assert( _bb_start <= _bb_end, "inverted block ends" );
2670
2671 // Compute the register antidependencies for the basic block
2672 ComputeRegisterAntidependencies(bb);
2673 if (C->failing()) return; // too many D-U pinch points
2674
2675 // Compute intra-bb latencies for the nodes
2676 ComputeLocalLatenciesForward(bb);
2677
2678 // Compute the usage within the block, and set the list of all nodes
2679 // in the block that have no uses within the block.
2680 ComputeUseCount(bb);
2681
2682 // Schedule the remaining instructions in the block
2683 while ( _available.size() > 0 ) {
2684 Node *n = ChooseNodeToBundle();
2685 guarantee(n != NULL, "no nodes available");
2686 AddNodeToBundle(n,bb);
2687 }
2688
2689 assert( _scheduled.size() == _bb_end - _bb_start, "wrong number of instructions" );
2690 #ifdef ASSERT
2691 for( uint l = _bb_start; l < _bb_end; l++ ) {
2692 Node *n = bb->get_node(l);
2693 uint m;
2694 for( m = 0; m < _bb_end-_bb_start; m++ )
2695 if( _scheduled[m] == n )
2696 break;
2697 assert( m < _bb_end-_bb_start, "instruction missing in schedule" );
2698 }
2699 #endif
2700
2701 // Now copy the instructions (in reverse order) back to the block
2702 for ( uint k = _bb_start; k < _bb_end; k++ )
2703 bb->map_node(_scheduled[_bb_end-k-1], k);
2704
2705 #ifndef PRODUCT
2706 if (_cfg->C->trace_opto_output()) {
2707 tty->print("# Schedule BB#%03d (final)\n", i);
2708 uint current = 0;
2709 for (uint j = 0; j < bb->number_of_nodes(); j++) {
2710 Node *n = bb->get_node(j);
2711 if( valid_bundle_info(n) ) {
2712 Bundle *bundle = node_bundling(n);
2713 if (bundle->instr_count() > 0 || bundle->flags() > 0) {
2714 tty->print("*** Bundle: ");
2715 bundle->dump();
2716 }
2717 n->dump();
2718 }
2719 }
2720 }
2721 #endif
2722 #ifdef ASSERT
2723 verify_good_schedule(bb,"after block local scheduling");
2724 #endif
2725 }
2726
2727 #ifndef PRODUCT
2728 if (_cfg->C->trace_opto_output())
2729 tty->print("# <- DoScheduling\n");
2730 #endif
2731
2732 // Record final node-bundling array location
2733 _regalloc->C->output()->set_node_bundling_base(_node_bundling_base);
2734
2735 } // end DoScheduling
2736
2737 // Verify that no live-range used in the block is killed in the block by a
2738 // wrong DEF. This doesn't verify live-ranges that span blocks.
2739
2740 // Check for edge existence. Used to avoid adding redundant precedence edges.
2741 static bool edge_from_to( Node *from, Node *to ) {
2742 for( uint i=0; i<from->len(); i++ )
2743 if( from->in(i) == to )
2744 return true;
2745 return false;
2746 }
2747
2748 #ifdef ASSERT
2749 void Scheduling::verify_do_def( Node *n, OptoReg::Name def, const char *msg ) {
2750 // Check for bad kills
2751 if( OptoReg::is_valid(def) ) { // Ignore stores & control flow
2752 Node *prior_use = _reg_node[def];
2753 if( prior_use && !edge_from_to(prior_use,n) ) {
2754 tty->print("%s = ",OptoReg::as_VMReg(def)->name());
2755 n->dump();
2756 tty->print_cr("...");
2757 prior_use->dump();
2758 assert(edge_from_to(prior_use,n), "%s", msg);
2759 }
2760 _reg_node.map(def,NULL); // Kill live USEs
2761 }
2762 }
2763
2764 void Scheduling::verify_good_schedule( Block *b, const char *msg ) {
2765
2766 // Zap to something reasonable for the verify code
2767 _reg_node.clear();
2768
2769 // Walk over the block backwards. Check to make sure each DEF doesn't
2770 // kill a live value (other than the one it's supposed to). Add each
2771 // USE to the live set.
2772 for( uint i = b->number_of_nodes()-1; i >= _bb_start; i-- ) {
2773 Node *n = b->get_node(i);
2774 int n_op = n->Opcode();
2775 if( n_op == Op_MachProj && n->ideal_reg() == MachProjNode::fat_proj ) {
2776 // Fat-proj kills a slew of registers
2777 RegMask rm = n->out_RegMask();// Make local copy
2778 while( rm.is_NotEmpty() ) {
2779 OptoReg::Name kill = rm.find_first_elem();
2780 rm.Remove(kill);
2781 verify_do_def( n, kill, msg );
2782 }
2783 } else if( n_op != Op_Node ) { // Avoid brand new antidependence nodes
2784 // Get DEF'd registers the normal way
2785 verify_do_def( n, _regalloc->get_reg_first(n), msg );
2786 verify_do_def( n, _regalloc->get_reg_second(n), msg );
2787 }
2788
2789 // Now make all USEs live
2790 for( uint i=1; i<n->req(); i++ ) {
2791 Node *def = n->in(i);
2792 assert(def != 0, "input edge required");
2793 OptoReg::Name reg_lo = _regalloc->get_reg_first(def);
2794 OptoReg::Name reg_hi = _regalloc->get_reg_second(def);
2795 if( OptoReg::is_valid(reg_lo) ) {
2796 assert(!_reg_node[reg_lo] || edge_from_to(_reg_node[reg_lo],def), "%s", msg);
2797 _reg_node.map(reg_lo,n);
2798 }
2799 if( OptoReg::is_valid(reg_hi) ) {
2800 assert(!_reg_node[reg_hi] || edge_from_to(_reg_node[reg_hi],def), "%s", msg);
2801 _reg_node.map(reg_hi,n);
2802 }
2803 }
2804
2805 }
2806
2807 // Zap to something reasonable for the Antidependence code
2808 _reg_node.clear();
2809 }
2810 #endif
2811
2812 // Conditionally add precedence edges. Avoid putting edges on Projs.
2813 static void add_prec_edge_from_to( Node *from, Node *to ) {
2814 if( from->is_Proj() ) { // Put precedence edge on Proj's input
2815 assert( from->req() == 1 && (from->len() == 1 || from->in(1)==0), "no precedence edges on projections" );
2816 from = from->in(0);
2817 }
2818 if( from != to && // No cycles (for things like LD L0,[L0+4] )
2819 !edge_from_to( from, to ) ) // Avoid duplicate edge
2820 from->add_prec(to);
2821 }
2822
2823 void Scheduling::anti_do_def( Block *b, Node *def, OptoReg::Name def_reg, int is_def ) {
2824 if( !OptoReg::is_valid(def_reg) ) // Ignore stores & control flow
2825 return;
2826
2827 Node *pinch = _reg_node[def_reg]; // Get pinch point
2828 if ((pinch == NULL) || _cfg->get_block_for_node(pinch) != b || // No pinch-point yet?
2829 is_def ) { // Check for a true def (not a kill)
2830 _reg_node.map(def_reg,def); // Record def/kill as the optimistic pinch-point
2831 return;
2832 }
2833
2834 Node *kill = def; // Rename 'def' to more descriptive 'kill'
2835 debug_only( def = (Node*)((intptr_t)0xdeadbeef); )
2836
2837 // After some number of kills there _may_ be a later def
2838 Node *later_def = NULL;
2839
2840 Compile* C = Compile::current();
2841
2842 // Finding a kill requires a real pinch-point.
2843 // Check for not already having a pinch-point.
2844 // Pinch points are Op_Node's.
2845 if( pinch->Opcode() != Op_Node ) { // Or later-def/kill as pinch-point?
2846 later_def = pinch; // Must be def/kill as optimistic pinch-point
2847 if ( _pinch_free_list.size() > 0) {
2848 pinch = _pinch_free_list.pop();
2849 } else {
2850 pinch = new Node(1); // Pinch point to-be
2851 }
2852 if (pinch->_idx >= _regalloc->node_regs_max_index()) {
2853 _cfg->C->record_method_not_compilable("too many D-U pinch points");
2854 return;
2855 }
2856 _cfg->map_node_to_block(pinch, b); // Pretend it's valid in this block (lazy init)
2857 _reg_node.map(def_reg,pinch); // Record pinch-point
2858 //regalloc()->set_bad(pinch->_idx); // Already initialized this way.
2859 if( later_def->outcnt() == 0 || later_def->ideal_reg() == MachProjNode::fat_proj ) { // Distinguish def from kill
2860 pinch->init_req(0, C->top()); // set not NULL for the next call
2861 add_prec_edge_from_to(later_def,pinch); // Add edge from kill to pinch
2862 later_def = NULL; // and no later def
2863 }
2864 pinch->set_req(0,later_def); // Hook later def so we can find it
2865 } else { // Else have valid pinch point
2866 if( pinch->in(0) ) // If there is a later-def
2867 later_def = pinch->in(0); // Get it
2868 }
2869
2870 // Add output-dependence edge from later def to kill
2871 if( later_def ) // If there is some original def
2872 add_prec_edge_from_to(later_def,kill); // Add edge from def to kill
2873
2874 // See if current kill is also a use, and so is forced to be the pinch-point.
2875 if( pinch->Opcode() == Op_Node ) {
2876 Node *uses = kill->is_Proj() ? kill->in(0) : kill;
2877 for( uint i=1; i<uses->req(); i++ ) {
2878 if( _regalloc->get_reg_first(uses->in(i)) == def_reg ||
2879 _regalloc->get_reg_second(uses->in(i)) == def_reg ) {
2880 // Yes, found a use/kill pinch-point
2881 pinch->set_req(0,NULL); //
2882 pinch->replace_by(kill); // Move anti-dep edges up
2883 pinch = kill;
2884 _reg_node.map(def_reg,pinch);
2885 return;
2886 }
2887 }
2888 }
2889
2890 // Add edge from kill to pinch-point
2891 add_prec_edge_from_to(kill,pinch);
2892 }
2893
2894 void Scheduling::anti_do_use( Block *b, Node *use, OptoReg::Name use_reg ) {
2895 if( !OptoReg::is_valid(use_reg) ) // Ignore stores & control flow
2896 return;
2897 Node *pinch = _reg_node[use_reg]; // Get pinch point
2898 // Check for no later def_reg/kill in block
2899 if ((pinch != NULL) && _cfg->get_block_for_node(pinch) == b &&
2900 // Use has to be block-local as well
2901 _cfg->get_block_for_node(use) == b) {
2902 if( pinch->Opcode() == Op_Node && // Real pinch-point (not optimistic?)
2903 pinch->req() == 1 ) { // pinch not yet in block?
2904 pinch->del_req(0); // yank pointer to later-def, also set flag
2905 // Insert the pinch-point in the block just after the last use
2906 b->insert_node(pinch, b->find_node(use) + 1);
2907 _bb_end++; // Increase size scheduled region in block
2908 }
2909
2910 add_prec_edge_from_to(pinch,use);
2911 }
2912 }
2913
2914 // We insert antidependences between the reads and following write of
2915 // allocated registers to prevent illegal code motion. Hopefully, the
2916 // number of added references should be fairly small, especially as we
2917 // are only adding references within the current basic block.
2918 void Scheduling::ComputeRegisterAntidependencies(Block *b) {
2919
2920 #ifdef ASSERT
2921 verify_good_schedule(b,"before block local scheduling");
2922 #endif
2923
2924 // A valid schedule, for each register independently, is an endless cycle
2925 // of: a def, then some uses (connected to the def by true dependencies),
2926 // then some kills (defs with no uses), finally the cycle repeats with a new
2927 // def. The uses are allowed to float relative to each other, as are the
2928 // kills. No use is allowed to slide past a kill (or def). This requires
2929 // antidependencies between all uses of a single def and all kills that
2930 // follow, up to the next def. More edges are redundant, because later defs
2931 // & kills are already serialized with true or antidependencies. To keep
2932 // the edge count down, we add a 'pinch point' node if there's more than
2933 // one use or more than one kill/def.
2934
2935 // We add dependencies in one bottom-up pass.
2936
2937 // For each instruction we handle it's DEFs/KILLs, then it's USEs.
2938
2939 // For each DEF/KILL, we check to see if there's a prior DEF/KILL for this
2940 // register. If not, we record the DEF/KILL in _reg_node, the
2941 // register-to-def mapping. If there is a prior DEF/KILL, we insert a
2942 // "pinch point", a new Node that's in the graph but not in the block.
2943 // We put edges from the prior and current DEF/KILLs to the pinch point.
2944 // We put the pinch point in _reg_node. If there's already a pinch point
2945 // we merely add an edge from the current DEF/KILL to the pinch point.
2946
2947 // After doing the DEF/KILLs, we handle USEs. For each used register, we
2948 // put an edge from the pinch point to the USE.
2949
2950 // To be expedient, the _reg_node array is pre-allocated for the whole
2951 // compilation. _reg_node is lazily initialized; it either contains a NULL,
2952 // or a valid def/kill/pinch-point, or a leftover node from some prior
2953 // block. Leftover node from some prior block is treated like a NULL (no
2954 // prior def, so no anti-dependence needed). Valid def is distinguished by
2955 // it being in the current block.
2956 bool fat_proj_seen = false;
2957 uint last_safept = _bb_end-1;
2958 Node* end_node = (_bb_end-1 >= _bb_start) ? b->get_node(last_safept) : NULL;
2959 Node* last_safept_node = end_node;
2960 for( uint i = _bb_end-1; i >= _bb_start; i-- ) {
2961 Node *n = b->get_node(i);
2962 int is_def = n->outcnt(); // def if some uses prior to adding precedence edges
2963 if( n->is_MachProj() && n->ideal_reg() == MachProjNode::fat_proj ) {
2964 // Fat-proj kills a slew of registers
2965 // This can add edges to 'n' and obscure whether or not it was a def,
2966 // hence the is_def flag.
2967 fat_proj_seen = true;
2968 RegMask rm = n->out_RegMask();// Make local copy
2969 while( rm.is_NotEmpty() ) {
2970 OptoReg::Name kill = rm.find_first_elem();
2971 rm.Remove(kill);
2972 anti_do_def( b, n, kill, is_def );
2973 }
2974 } else {
2975 // Get DEF'd registers the normal way
2976 anti_do_def( b, n, _regalloc->get_reg_first(n), is_def );
2977 anti_do_def( b, n, _regalloc->get_reg_second(n), is_def );
2978 }
2979
2980 // Kill projections on a branch should appear to occur on the
2981 // branch, not afterwards, so grab the masks from the projections
2982 // and process them.
2983 if (n->is_MachBranch() || (n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_Jump)) {
2984 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2985 Node* use = n->fast_out(i);
2986 if (use->is_Proj()) {
2987 RegMask rm = use->out_RegMask();// Make local copy
2988 while( rm.is_NotEmpty() ) {
2989 OptoReg::Name kill = rm.find_first_elem();
2990 rm.Remove(kill);
2991 anti_do_def( b, n, kill, false );
2992 }
2993 }
2994 }
2995 }
2996
2997 // Check each register used by this instruction for a following DEF/KILL
2998 // that must occur afterward and requires an anti-dependence edge.
2999 for( uint j=0; j<n->req(); j++ ) {
3000 Node *def = n->in(j);
3001 if( def ) {
3002 assert( !def->is_MachProj() || def->ideal_reg() != MachProjNode::fat_proj, "" );
3003 anti_do_use( b, n, _regalloc->get_reg_first(def) );
3004 anti_do_use( b, n, _regalloc->get_reg_second(def) );
3005 }
3006 }
3007 // Do not allow defs of new derived values to float above GC
3008 // points unless the base is definitely available at the GC point.
3009
3010 Node *m = b->get_node(i);
3011
3012 // Add precedence edge from following safepoint to use of derived pointer
3013 if( last_safept_node != end_node &&
3014 m != last_safept_node) {
3015 for (uint k = 1; k < m->req(); k++) {
3016 const Type *t = m->in(k)->bottom_type();
3017 if( t->isa_oop_ptr() &&
3018 t->is_ptr()->offset() != 0 ) {
3019 last_safept_node->add_prec( m );
3020 break;
3021 }
3022 }
3023 }
3024
3025 if( n->jvms() ) { // Precedence edge from derived to safept
3026 // Check if last_safept_node was moved by pinch-point insertion in anti_do_use()
3027 if( b->get_node(last_safept) != last_safept_node ) {
3028 last_safept = b->find_node(last_safept_node);
3029 }
3030 for( uint j=last_safept; j > i; j-- ) {
3031 Node *mach = b->get_node(j);
3032 if( mach->is_Mach() && mach->as_Mach()->ideal_Opcode() == Op_AddP )
3033 mach->add_prec( n );
3034 }
3035 last_safept = i;
3036 last_safept_node = m;
3037 }
3038 }
3039
3040 if (fat_proj_seen) {
3041 // Garbage collect pinch nodes that were not consumed.
3042 // They are usually created by a fat kill MachProj for a call.
3043 garbage_collect_pinch_nodes();
3044 }
3045 }
3046
3047 // Garbage collect pinch nodes for reuse by other blocks.
3048 //
3049 // The block scheduler's insertion of anti-dependence
3050 // edges creates many pinch nodes when the block contains
3051 // 2 or more Calls. A pinch node is used to prevent a
3052 // combinatorial explosion of edges. If a set of kills for a
3053 // register is anti-dependent on a set of uses (or defs), rather
3054 // than adding an edge in the graph between each pair of kill
3055 // and use (or def), a pinch is inserted between them:
3056 //
3057 // use1 use2 use3
3058 // \ | /
3059 // \ | /
3060 // pinch
3061 // / | \
3062 // / | \
3063 // kill1 kill2 kill3
3064 //
3065 // One pinch node is created per register killed when
3066 // the second call is encountered during a backwards pass
3067 // over the block. Most of these pinch nodes are never
3068 // wired into the graph because the register is never
3069 // used or def'ed in the block.
3070 //
3071 void Scheduling::garbage_collect_pinch_nodes() {
3072 #ifndef PRODUCT
3073 if (_cfg->C->trace_opto_output()) tty->print("Reclaimed pinch nodes:");
3074 #endif
3075 int trace_cnt = 0;
3076 for (uint k = 0; k < _reg_node.Size(); k++) {
3077 Node* pinch = _reg_node[k];
3078 if ((pinch != NULL) && pinch->Opcode() == Op_Node &&
3079 // no predecence input edges
3080 (pinch->req() == pinch->len() || pinch->in(pinch->req()) == NULL) ) {
3081 cleanup_pinch(pinch);
3082 _pinch_free_list.push(pinch);
3083 _reg_node.map(k, NULL);
3084 #ifndef PRODUCT
3085 if (_cfg->C->trace_opto_output()) {
3086 trace_cnt++;
3087 if (trace_cnt > 40) {
3088 tty->print("\n");
3089 trace_cnt = 0;
3090 }
3091 tty->print(" %d", pinch->_idx);
3092 }
3093 #endif
3094 }
3095 }
3096 #ifndef PRODUCT
3097 if (_cfg->C->trace_opto_output()) tty->print("\n");
3098 #endif
3099 }
3100
3101 // Clean up a pinch node for reuse.
3102 void Scheduling::cleanup_pinch( Node *pinch ) {
3103 assert (pinch && pinch->Opcode() == Op_Node && pinch->req() == 1, "just checking");
3104
3105 for (DUIterator_Last imin, i = pinch->last_outs(imin); i >= imin; ) {
3106 Node* use = pinch->last_out(i);
3107 uint uses_found = 0;
3108 for (uint j = use->req(); j < use->len(); j++) {
3109 if (use->in(j) == pinch) {
3110 use->rm_prec(j);
3111 uses_found++;
3112 }
3113 }
3114 assert(uses_found > 0, "must be a precedence edge");
3115 i -= uses_found; // we deleted 1 or more copies of this edge
3116 }
3117 // May have a later_def entry
3118 pinch->set_req(0, NULL);
3119 }
3120
3121 #ifndef PRODUCT
3122
3123 void Scheduling::dump_available() const {
3124 tty->print("#Availist ");
3125 for (uint i = 0; i < _available.size(); i++)
3126 tty->print(" N%d/l%d", _available[i]->_idx,_current_latency[_available[i]->_idx]);
3127 tty->cr();
3128 }
3129
3130 // Print Scheduling Statistics
3131 void Scheduling::print_statistics() {
3132 // Print the size added by nops for bundling
3133 tty->print("Nops added %d bytes to total of %d bytes",
3134 _total_nop_size, _total_method_size);
3135 if (_total_method_size > 0)
3136 tty->print(", for %.2f%%",
3137 ((double)_total_nop_size) / ((double) _total_method_size) * 100.0);
3138 tty->print("\n");
3139
3140 // Print the number of branch shadows filled
3141 if (Pipeline::_branch_has_delay_slot) {
3142 tty->print("Of %d branches, %d had unconditional delay slots filled",
3143 _total_branches, _total_unconditional_delays);
3144 if (_total_branches > 0)
3145 tty->print(", for %.2f%%",
3146 ((double)_total_unconditional_delays) / ((double)_total_branches) * 100.0);
3147 tty->print("\n");
3148 }
3149
3150 uint total_instructions = 0, total_bundles = 0;
3151
3152 for (uint i = 1; i <= Pipeline::_max_instrs_per_cycle; i++) {
3153 uint bundle_count = _total_instructions_per_bundle[i];
3154 total_instructions += bundle_count * i;
3155 total_bundles += bundle_count;
3156 }
3157
3158 if (total_bundles > 0)
3159 tty->print("Average ILP (excluding nops) is %.2f\n",
3160 ((double)total_instructions) / ((double)total_bundles));
3161 }
3162 #endif
3163
3164 //-----------------------init_scratch_buffer_blob------------------------------
3165 // Construct a temporary BufferBlob and cache it for this compile.
3166 void PhaseOutput::init_scratch_buffer_blob(int const_size) {
3167 // If there is already a scratch buffer blob allocated and the
3168 // constant section is big enough, use it. Otherwise free the
3169 // current and allocate a new one.
3170 BufferBlob* blob = scratch_buffer_blob();
3171 if ((blob != NULL) && (const_size <= _scratch_const_size)) {
3172 // Use the current blob.
3173 } else {
3174 if (blob != NULL) {
3175 BufferBlob::free(blob);
3176 }
3177
3178 ResourceMark rm;
3179 _scratch_const_size = const_size;
3180 int size = C2Compiler::initial_code_buffer_size(const_size);
3181 blob = BufferBlob::create("Compile::scratch_buffer", size);
3182 // Record the buffer blob for next time.
3183 set_scratch_buffer_blob(blob);
3184 // Have we run out of code space?
3185 if (scratch_buffer_blob() == NULL) {
3186 // Let CompilerBroker disable further compilations.
3187 C->record_failure("Not enough space for scratch buffer in CodeCache");
3188 return;
3189 }
3190 }
3191
3192 // Initialize the relocation buffers
3193 relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
3194 set_scratch_locs_memory(locs_buf);
3195 }
3196
3197
3198 //-----------------------scratch_emit_size-------------------------------------
3199 // Helper function that computes size by emitting code
3200 uint PhaseOutput::scratch_emit_size(const Node* n) {
3201 // Start scratch_emit_size section.
3202 set_in_scratch_emit_size(true);
3203
3204 // Emit into a trash buffer and count bytes emitted.
3205 // This is a pretty expensive way to compute a size,
3206 // but it works well enough if seldom used.
3207 // All common fixed-size instructions are given a size
3208 // method by the AD file.
3209 // Note that the scratch buffer blob and locs memory are
3210 // allocated at the beginning of the compile task, and
3211 // may be shared by several calls to scratch_emit_size.
3212 // The allocation of the scratch buffer blob is particularly
3213 // expensive, since it has to grab the code cache lock.
3214 BufferBlob* blob = this->scratch_buffer_blob();
3215 assert(blob != NULL, "Initialize BufferBlob at start");
3216 assert(blob->size() > MAX_inst_size, "sanity");
3217 relocInfo* locs_buf = scratch_locs_memory();
3218 address blob_begin = blob->content_begin();
3219 address blob_end = (address)locs_buf;
3220 assert(blob->contains(blob_end), "sanity");
3221 CodeBuffer buf(blob_begin, blob_end - blob_begin);
3222 buf.initialize_consts_size(_scratch_const_size);
3223 buf.initialize_stubs_size(MAX_stubs_size);
3224 assert(locs_buf != NULL, "sanity");
3225 int lsize = MAX_locs_size / 3;
3226 buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
3227 buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
3228 buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
3229 // Mark as scratch buffer.
3230 buf.consts()->set_scratch_emit();
3231 buf.insts()->set_scratch_emit();
3232 buf.stubs()->set_scratch_emit();
3233
3234 // Do the emission.
3235
3236 Label fakeL; // Fake label for branch instructions.
3237 Label* saveL = NULL;
3238 uint save_bnum = 0;
3239 bool is_branch = n->is_MachBranch();
3240 if (is_branch) {
3241 MacroAssembler masm(&buf);
3242 masm.bind(fakeL);
3243 n->as_MachBranch()->save_label(&saveL, &save_bnum);
3244 n->as_MachBranch()->label_set(&fakeL, 0);
3245 }
3246 n->emit(buf, C->regalloc());
3247
3248 // Emitting into the scratch buffer should not fail
3249 assert (!C->failing(), "Must not have pending failure. Reason is: %s", C->failure_reason());
3250
3251 if (is_branch) // Restore label.
3252 n->as_MachBranch()->label_set(saveL, save_bnum);
3253
3254 // End scratch_emit_size section.
3255 set_in_scratch_emit_size(false);
3256
3257 return buf.insts_size();
3258 }
3259
3260 void PhaseOutput::install() {
3261 if (C->stub_function() != NULL) {
3262 install_stub(C->stub_name(),
3263 C->save_argument_registers());
3264 } else {
3265 install_code(C->method(),
3266 C->entry_bci(),
3267 CompileBroker::compiler2(),
3268 C->has_unsafe_access(),
3269 SharedRuntime::is_wide_vector(C->max_vector_size()),
3270 C->rtm_state());
3271 }
3272 }
3273
3274 void PhaseOutput::install_code(ciMethod* target,
3275 int entry_bci,
3276 AbstractCompiler* compiler,
3277 bool has_unsafe_access,
3278 bool has_wide_vectors,
3279 RTMState rtm_state) {
3280 // Check if we want to skip execution of all compiled code.
3281 {
3282 #ifndef PRODUCT
3283 if (OptoNoExecute) {
3284 C->record_method_not_compilable("+OptoNoExecute"); // Flag as failed
3285 return;
3286 }
3287 #endif
3288 Compile::TracePhase tp("install_code", &timers[_t_registerMethod]);
3289
3290 if (C->is_osr_compilation()) {
3291 _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
3292 _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
3293 } else {
3294 _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
3295 _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
3296 }
3297
3298 C->env()->register_method(target,
3299 entry_bci,
3300 &_code_offsets,
3301 _orig_pc_slot_offset_in_bytes,
3302 code_buffer(),
3303 frame_size_in_words(),
3304 oop_map_set(),
3305 &_handler_table,
3306 inc_table(),
3307 compiler,
3308 has_unsafe_access,
3309 SharedRuntime::is_wide_vector(C->max_vector_size()),
3310 C->rtm_state());
3311
3312 if (C->log() != NULL) { // Print code cache state into compiler log
3313 C->log()->code_cache_state();
3314 }
3315 }
3316 }
3317 void PhaseOutput::install_stub(const char* stub_name,
3318 bool caller_must_gc_arguments) {
3319 // Entry point will be accessed using stub_entry_point();
3320 if (code_buffer() == NULL) {
3321 Matcher::soft_match_failure();
3322 } else {
3323 if (PrintAssembly && (WizardMode || Verbose))
3324 tty->print_cr("### Stub::%s", stub_name);
3325
3326 if (!C->failing()) {
3327 assert(C->fixed_slots() == 0, "no fixed slots used for runtime stubs");
3328
3329 // Make the NMethod
3330 // For now we mark the frame as never safe for profile stackwalking
3331 RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
3332 code_buffer(),
3333 CodeOffsets::frame_never_safe,
3334 // _code_offsets.value(CodeOffsets::Frame_Complete),
3335 frame_size_in_words(),
3336 oop_map_set(),
3337 caller_must_gc_arguments);
3338 assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
3339
3340 C->set_stub_entry_point(rs->entry_point());
3341 }
3342 }
3343 }
3344
3345 // Support for bundling info
3346 Bundle* PhaseOutput::node_bundling(const Node *n) {
3347 assert(valid_bundle_info(n), "oob");
3348 return &_node_bundling_base[n->_idx];
3349 }
3350
3351 bool PhaseOutput::valid_bundle_info(const Node *n) {
3352 return (_node_bundling_limit > n->_idx);
3353 }
3354
3355 //------------------------------frame_size_in_words-----------------------------
3356 // frame_slots in units of words
3357 int PhaseOutput::frame_size_in_words() const {
3358 // shift is 0 in LP32 and 1 in LP64
3359 const int shift = (LogBytesPerWord - LogBytesPerInt);
3360 int words = _frame_slots >> shift;
3361 assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
3362 return words;
3363 }
3364
3365 // To bang the stack of this compiled method we use the stack size
3366 // that the interpreter would need in case of a deoptimization. This
3367 // removes the need to bang the stack in the deoptimization blob which
3368 // in turn simplifies stack overflow handling.
3369 int PhaseOutput::bang_size_in_bytes() const {
3370 return MAX2(frame_size_in_bytes() + os::extra_bang_size_in_bytes(), C->interpreter_frame_size());
3371 }
3372
3373 //------------------------------dump_asm---------------------------------------
3374 // Dump formatted assembly
3375 #if defined(SUPPORT_OPTO_ASSEMBLY)
3376 void PhaseOutput::dump_asm_on(outputStream* st, int* pcs, uint pc_limit) {
3377
3378 int pc_digits = 3; // #chars required for pc
3379 int sb_chars = 3; // #chars for "start bundle" indicator
3380 int tab_size = 8;
3381 if (pcs != NULL) {
3382 int max_pc = 0;
3383 for (uint i = 0; i < pc_limit; i++) {
3384 max_pc = (max_pc < pcs[i]) ? pcs[i] : max_pc;
3385 }
3386 pc_digits = ((max_pc < 4096) ? 3 : ((max_pc < 65536) ? 4 : ((max_pc < 65536*256) ? 6 : 8))); // #chars required for pc
3387 }
3388 int prefix_len = ((pc_digits + sb_chars + tab_size - 1)/tab_size)*tab_size;
3389
3390 bool cut_short = false;
3391 st->print_cr("#");
3392 st->print("# "); C->tf()->dump_on(st); st->cr();
3393 st->print_cr("#");
3394
3395 // For all blocks
3396 int pc = 0x0; // Program counter
3397 char starts_bundle = ' ';
3398 C->regalloc()->dump_frame();
3399
3400 Node *n = NULL;
3401 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) {
3402 if (VMThread::should_terminate()) {
3403 cut_short = true;
3404 break;
3405 }
3406 Block* block = C->cfg()->get_block(i);
3407 if (block->is_connector() && !Verbose) {
3408 continue;
3409 }
3410 n = block->head();
3411 if ((pcs != NULL) && (n->_idx < pc_limit)) {
3412 pc = pcs[n->_idx];
3413 st->print("%*.*x", pc_digits, pc_digits, pc);
3414 }
3415 st->fill_to(prefix_len);
3416 block->dump_head(C->cfg(), st);
3417 if (block->is_connector()) {
3418 st->fill_to(prefix_len);
3419 st->print_cr("# Empty connector block");
3420 } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
3421 st->fill_to(prefix_len);
3422 st->print_cr("# Block is sole successor of call");
3423 }
3424
3425 // For all instructions
3426 Node *delay = NULL;
3427 for (uint j = 0; j < block->number_of_nodes(); j++) {
3428 if (VMThread::should_terminate()) {
3429 cut_short = true;
3430 break;
3431 }
3432 n = block->get_node(j);
3433 if (valid_bundle_info(n)) {
3434 Bundle* bundle = node_bundling(n);
3435 if (bundle->used_in_unconditional_delay()) {
3436 delay = n;
3437 continue;
3438 }
3439 if (bundle->starts_bundle()) {
3440 starts_bundle = '+';
3441 }
3442 }
3443
3444 if (WizardMode) {
3445 n->dump();
3446 }
3447
3448 if( !n->is_Region() && // Dont print in the Assembly
3449 !n->is_Phi() && // a few noisely useless nodes
3450 !n->is_Proj() &&
3451 !n->is_MachTemp() &&
3452 !n->is_SafePointScalarObject() &&
3453 !n->is_Catch() && // Would be nice to print exception table targets
3454 !n->is_MergeMem() && // Not very interesting
3455 !n->is_top() && // Debug info table constants
3456 !(n->is_Con() && !n->is_Mach())// Debug info table constants
3457 ) {
3458 if ((pcs != NULL) && (n->_idx < pc_limit)) {
3459 pc = pcs[n->_idx];
3460 st->print("%*.*x", pc_digits, pc_digits, pc);
3461 } else {
3462 st->fill_to(pc_digits);
3463 }
3464 st->print(" %c ", starts_bundle);
3465 starts_bundle = ' ';
3466 st->fill_to(prefix_len);
3467 n->format(C->regalloc(), st);
3468 st->cr();
3469 }
3470
3471 // If we have an instruction with a delay slot, and have seen a delay,
3472 // then back up and print it
3473 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
3474 // Coverity finding - Explicit null dereferenced.
3475 guarantee(delay != NULL, "no unconditional delay instruction");
3476 if (WizardMode) delay->dump();
3477
3478 if (node_bundling(delay)->starts_bundle())
3479 starts_bundle = '+';
3480 if ((pcs != NULL) && (n->_idx < pc_limit)) {
3481 pc = pcs[n->_idx];
3482 st->print("%*.*x", pc_digits, pc_digits, pc);
3483 } else {
3484 st->fill_to(pc_digits);
3485 }
3486 st->print(" %c ", starts_bundle);
3487 starts_bundle = ' ';
3488 st->fill_to(prefix_len);
3489 delay->format(C->regalloc(), st);
3490 st->cr();
3491 delay = NULL;
3492 }
3493
3494 // Dump the exception table as well
3495 if( n->is_Catch() && (Verbose || WizardMode) ) {
3496 // Print the exception table for this offset
3497 _handler_table.print_subtable_for(pc);
3498 }
3499 st->bol(); // Make sure we start on a new line
3500 }
3501 st->cr(); // one empty line between blocks
3502 assert(cut_short || delay == NULL, "no unconditional delay branch");
3503 } // End of per-block dump
3504
3505 if (cut_short) st->print_cr("*** disassembly is cut short ***");
3506 }
3507 #endif
3508
3509 #ifndef PRODUCT
3510 void PhaseOutput::print_statistics() {
3511 Scheduling::print_statistics();
3512 }
3513 #endif