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 if( t->base() == Type::DoubleBot || t->base() == Type::DoubleCon || t->base() == Type::Long ) {
808 // Repack the double/long as two jints.
809 // The convention the interpreter uses is that the second local
810 // holds the first raw word of the native double representation.
811 // This is actually reasonable, since locals and stack arrays
812 // grow downwards in all implementations.
813 // (If, on some machine, the interpreter's Java locals or stack
814 // were to grow upwards, the embedded doubles would be word-swapped.)
815 array->append(new_loc_value( C->regalloc(), OptoReg::add(regnum,1), Location::normal ));
816 array->append(new_loc_value( C->regalloc(), regnum , Location::normal ));
817 }
818 #endif //_LP64
819 else if( (t->base() == Type::FloatBot || t->base() == Type::FloatCon) &&
820 OptoReg::is_reg(regnum) ) {
821 array->append(new_loc_value( C->regalloc(), regnum, Matcher::float_in_double()
822 ? Location::float_in_dbl : Location::normal ));
823 } else if( t->base() == Type::Int && OptoReg::is_reg(regnum) ) {
824 array->append(new_loc_value( C->regalloc(), regnum, Matcher::int_in_long
825 ? Location::int_in_long : Location::normal ));
826 } else if( t->base() == Type::NarrowOop ) {
827 array->append(new_loc_value( C->regalloc(), regnum, Location::narrowoop ));
828 } else {
829 array->append(new_loc_value( C->regalloc(), regnum, C->regalloc()->is_oop(local) ? Location::oop : Location::normal ));
830 }
831 return;
832 }
833
834 // No register. It must be constant data.
835 switch (t->base()) {
836 case Type::Half: // Second half of a double
837 ShouldNotReachHere(); // Caller should skip 2nd halves
838 break;
839 case Type::AnyPtr:
840 array->append(new ConstantOopWriteValue(NULL));
841 break;
842 case Type::AryPtr:
843 case Type::InstPtr: // fall through
844 array->append(new ConstantOopWriteValue(t->isa_oopptr()->const_oop()->constant_encoding()));
845 break;
846 case Type::NarrowOop:
847 if (t == TypeNarrowOop::NULL_PTR) {
848 array->append(new ConstantOopWriteValue(NULL));
849 } else {
850 array->append(new ConstantOopWriteValue(t->make_ptr()->isa_oopptr()->const_oop()->constant_encoding()));
851 }
852 break;
853 case Type::Int:
854 array->append(new ConstantIntValue(t->is_int()->get_con()));
855 break;
856 case Type::RawPtr:
857 // A return address (T_ADDRESS).
858 assert((intptr_t)t->is_ptr()->get_con() < (intptr_t)0x10000, "must be a valid BCI");
859 #ifdef _LP64
860 // Must be restored to the full-width 64-bit stack slot.
861 array->append(new ConstantLongValue(t->is_ptr()->get_con()));
862 #else
863 array->append(new ConstantIntValue(t->is_ptr()->get_con()));
864 #endif
865 break;
866 case Type::FloatCon: {
867 float f = t->is_float_constant()->getf();
868 array->append(new ConstantIntValue(jint_cast(f)));
869 break;
870 }
871 case Type::DoubleCon: {
872 jdouble d = t->is_double_constant()->getd();
873 #ifdef _LP64
874 array->append(new ConstantIntValue((jint)0));
875 array->append(new ConstantDoubleValue(d));
876 #else
877 // Repack the double as two jints.
878 // The convention the interpreter uses is that the second local
879 // holds the first raw word of the native double representation.
880 // This is actually reasonable, since locals and stack arrays
881 // grow downwards in all implementations.
882 // (If, on some machine, the interpreter's Java locals or stack
883 // were to grow upwards, the embedded doubles would be word-swapped.)
884 jlong_accessor acc;
885 acc.long_value = jlong_cast(d);
886 array->append(new ConstantIntValue(acc.words[1]));
887 array->append(new ConstantIntValue(acc.words[0]));
888 #endif
889 break;
890 }
891 case Type::Long: {
892 jlong d = t->is_long()->get_con();
893 #ifdef _LP64
894 array->append(new ConstantIntValue((jint)0));
895 array->append(new ConstantLongValue(d));
896 #else
897 // Repack the long as two jints.
898 // The convention the interpreter uses is that the second local
899 // holds the first raw word of the native double representation.
900 // This is actually reasonable, since locals and stack arrays
901 // grow downwards in all implementations.
902 // (If, on some machine, the interpreter's Java locals or stack
903 // were to grow upwards, the embedded doubles would be word-swapped.)
904 jlong_accessor acc;
905 acc.long_value = d;
906 array->append(new ConstantIntValue(acc.words[1]));
907 array->append(new ConstantIntValue(acc.words[0]));
908 #endif
909 break;
910 }
911 case Type::Top: // Add an illegal value here
912 array->append(new LocationValue(Location()));
913 break;
914 default:
915 ShouldNotReachHere();
916 break;
917 }
918 }
919
920 // Determine if this node starts a bundle
921 bool PhaseOutput::starts_bundle(const Node *n) const {
922 return (_node_bundling_limit > n->_idx &&
923 _node_bundling_base[n->_idx].starts_bundle());
924 }
925
926 //--------------------------Process_OopMap_Node--------------------------------
927 void PhaseOutput::Process_OopMap_Node(MachNode *mach, int current_offset) {
928 // Handle special safepoint nodes for synchronization
929 MachSafePointNode *sfn = mach->as_MachSafePoint();
930 MachCallNode *mcall;
931
932 int safepoint_pc_offset = current_offset;
933 bool is_method_handle_invoke = false;
934 bool return_oop = false;
935
936 // Add the safepoint in the DebugInfoRecorder
937 if( !mach->is_MachCall() ) {
938 mcall = NULL;
939 C->debug_info()->add_safepoint(safepoint_pc_offset, sfn->_oop_map);
940 } else {
941 mcall = mach->as_MachCall();
942
943 // Is the call a MethodHandle call?
944 if (mcall->is_MachCallJava()) {
945 if (mcall->as_MachCallJava()->_method_handle_invoke) {
946 assert(C->has_method_handle_invokes(), "must have been set during call generation");
947 is_method_handle_invoke = true;
948 }
949 }
950
951 // Check if a call returns an object.
952 if (mcall->returns_pointer()) {
953 return_oop = true;
954 }
955 safepoint_pc_offset += mcall->ret_addr_offset();
956 C->debug_info()->add_safepoint(safepoint_pc_offset, mcall->_oop_map);
957 }
958
959 // Loop over the JVMState list to add scope information
960 // Do not skip safepoints with a NULL method, they need monitor info
961 JVMState* youngest_jvms = sfn->jvms();
962 int max_depth = youngest_jvms->depth();
963
964 // Allocate the object pool for scalar-replaced objects -- the map from
965 // small-integer keys (which can be recorded in the local and ostack
966 // arrays) to descriptions of the object state.
967 GrowableArray<ScopeValue*> *objs = new GrowableArray<ScopeValue*>();
968
969 // Visit scopes from oldest to youngest.
970 for (int depth = 1; depth <= max_depth; depth++) {
971 JVMState* jvms = youngest_jvms->of_depth(depth);
972 int idx;
973 ciMethod* method = jvms->has_method() ? jvms->method() : NULL;
974 // Safepoints that do not have method() set only provide oop-map and monitor info
975 // to support GC; these do not support deoptimization.
976 int num_locs = (method == NULL) ? 0 : jvms->loc_size();
977 int num_exps = (method == NULL) ? 0 : jvms->stk_size();
978 int num_mon = jvms->nof_monitors();
979 assert(method == NULL || jvms->bci() < 0 || num_locs == method->max_locals(),
980 "JVMS local count must match that of the method");
981
982 // Add Local and Expression Stack Information
983
984 // Insert locals into the locarray
985 GrowableArray<ScopeValue*> *locarray = new GrowableArray<ScopeValue*>(num_locs);
986 for( idx = 0; idx < num_locs; idx++ ) {
987 FillLocArray( idx, sfn, sfn->local(jvms, idx), locarray, objs );
988 }
989
990 // Insert expression stack entries into the exparray
991 GrowableArray<ScopeValue*> *exparray = new GrowableArray<ScopeValue*>(num_exps);
992 for( idx = 0; idx < num_exps; idx++ ) {
993 FillLocArray( idx, sfn, sfn->stack(jvms, idx), exparray, objs );
994 }
995
996 // Add in mappings of the monitors
997 assert( !method ||
998 !method->is_synchronized() ||
999 method->is_native() ||
1000 num_mon > 0 ||
1001 !GenerateSynchronizationCode,
1002 "monitors must always exist for synchronized methods");
1003
1004 // Build the growable array of ScopeValues for exp stack
1005 GrowableArray<MonitorValue*> *monarray = new GrowableArray<MonitorValue*>(num_mon);
1006
1007 // Loop over monitors and insert into array
1008 for (idx = 0; idx < num_mon; idx++) {
1009 // Grab the node that defines this monitor
1010 Node* box_node = sfn->monitor_box(jvms, idx);
1011 Node* obj_node = sfn->monitor_obj(jvms, idx);
1012
1013 // Create ScopeValue for object
1014 ScopeValue *scval = NULL;
1015
1016 if (obj_node->is_SafePointScalarObject()) {
1017 SafePointScalarObjectNode* spobj = obj_node->as_SafePointScalarObject();
1018 scval = PhaseOutput::sv_for_node_id(objs, spobj->_idx);
1019 if (scval == NULL) {
1020 const Type *t = spobj->bottom_type();
1021 ciKlass* cik = t->is_oopptr()->klass();
1022 assert(cik->is_instance_klass() ||
1023 cik->is_array_klass(), "Not supported allocation.");
1024 ObjectValue* sv = new ObjectValue(spobj->_idx,
1025 new ConstantOopWriteValue(cik->java_mirror()->constant_encoding()));
1026 PhaseOutput::set_sv_for_object_node(objs, sv);
1027
1028 uint first_ind = spobj->first_index(youngest_jvms);
1029 for (uint i = 0; i < spobj->n_fields(); i++) {
1030 Node* fld_node = sfn->in(first_ind+i);
1031 (void)FillLocArray(sv->field_values()->length(), sfn, fld_node, sv->field_values(), objs);
1032 }
1033 scval = sv;
1034 }
1035 } else if (!obj_node->is_Con()) {
1036 OptoReg::Name obj_reg = C->regalloc()->get_reg_first(obj_node);
1037 if( obj_node->bottom_type()->base() == Type::NarrowOop ) {
1038 scval = new_loc_value( C->regalloc(), obj_reg, Location::narrowoop );
1039 } else {
1040 scval = new_loc_value( C->regalloc(), obj_reg, Location::oop );
1041 }
1042 } else {
1043 const TypePtr *tp = obj_node->get_ptr_type();
1044 scval = new ConstantOopWriteValue(tp->is_oopptr()->const_oop()->constant_encoding());
1045 }
1046
1047 OptoReg::Name box_reg = BoxLockNode::reg(box_node);
1048 Location basic_lock = Location::new_stk_loc(Location::normal,C->regalloc()->reg2offset(box_reg));
1049 bool eliminated = (box_node->is_BoxLock() && box_node->as_BoxLock()->is_eliminated());
1050 monarray->append(new MonitorValue(scval, basic_lock, eliminated));
1051 }
1052
1053 // We dump the object pool first, since deoptimization reads it in first.
1054 C->debug_info()->dump_object_pool(objs);
1055
1056 // Build first class objects to pass to scope
1057 DebugToken *locvals = C->debug_info()->create_scope_values(locarray);
1058 DebugToken *expvals = C->debug_info()->create_scope_values(exparray);
1059 DebugToken *monvals = C->debug_info()->create_monitor_values(monarray);
1060
1061 // Make method available for all Safepoints
1062 ciMethod* scope_method = method ? method : C->method();
1063 // Describe the scope here
1064 assert(jvms->bci() >= InvocationEntryBci && jvms->bci() <= 0x10000, "must be a valid or entry BCI");
1065 assert(!jvms->should_reexecute() || depth == max_depth, "reexecute allowed only for the youngest");
1066 // Now we can describe the scope.
1067 methodHandle null_mh;
1068 bool rethrow_exception = false;
1069 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);
1070 } // End jvms loop
1071
1072 // Mark the end of the scope set.
1073 C->debug_info()->end_safepoint(safepoint_pc_offset);
1074 }
1075
1076
1077
1078 // A simplified version of Process_OopMap_Node, to handle non-safepoints.
1079 class NonSafepointEmitter {
1080 Compile* C;
1081 JVMState* _pending_jvms;
1082 int _pending_offset;
1083
1084 void emit_non_safepoint();
1085
1086 public:
1087 NonSafepointEmitter(Compile* compile) {
1088 this->C = compile;
1089 _pending_jvms = NULL;
1090 _pending_offset = 0;
1091 }
1092
1093 void observe_instruction(Node* n, int pc_offset) {
1094 if (!C->debug_info()->recording_non_safepoints()) return;
1095
1096 Node_Notes* nn = C->node_notes_at(n->_idx);
1097 if (nn == NULL || nn->jvms() == NULL) return;
1098 if (_pending_jvms != NULL &&
1099 _pending_jvms->same_calls_as(nn->jvms())) {
1100 // Repeated JVMS? Stretch it up here.
1101 _pending_offset = pc_offset;
1102 } else {
1103 if (_pending_jvms != NULL &&
1104 _pending_offset < pc_offset) {
1105 emit_non_safepoint();
1106 }
1107 _pending_jvms = NULL;
1108 if (pc_offset > C->debug_info()->last_pc_offset()) {
1109 // This is the only way _pending_jvms can become non-NULL:
1110 _pending_jvms = nn->jvms();
1111 _pending_offset = pc_offset;
1112 }
1113 }
1114 }
1115
1116 // Stay out of the way of real safepoints:
1117 void observe_safepoint(JVMState* jvms, int pc_offset) {
1118 if (_pending_jvms != NULL &&
1119 !_pending_jvms->same_calls_as(jvms) &&
1120 _pending_offset < pc_offset) {
1121 emit_non_safepoint();
1122 }
1123 _pending_jvms = NULL;
1124 }
1125
1126 void flush_at_end() {
1127 if (_pending_jvms != NULL) {
1128 emit_non_safepoint();
1129 }
1130 _pending_jvms = NULL;
1131 }
1132 };
1133
1134 void NonSafepointEmitter::emit_non_safepoint() {
1135 JVMState* youngest_jvms = _pending_jvms;
1136 int pc_offset = _pending_offset;
1137
1138 // Clear it now:
1139 _pending_jvms = NULL;
1140
1141 DebugInformationRecorder* debug_info = C->debug_info();
1142 assert(debug_info->recording_non_safepoints(), "sanity");
1143
1144 debug_info->add_non_safepoint(pc_offset);
1145 int max_depth = youngest_jvms->depth();
1146
1147 // Visit scopes from oldest to youngest.
1148 for (int depth = 1; depth <= max_depth; depth++) {
1149 JVMState* jvms = youngest_jvms->of_depth(depth);
1150 ciMethod* method = jvms->has_method() ? jvms->method() : NULL;
1151 assert(!jvms->should_reexecute() || depth==max_depth, "reexecute allowed only for the youngest");
1152 methodHandle null_mh;
1153 debug_info->describe_scope(pc_offset, null_mh, method, jvms->bci(), jvms->should_reexecute());
1154 }
1155
1156 // Mark the end of the scope set.
1157 debug_info->end_non_safepoint(pc_offset);
1158 }
1159
1160 //------------------------------init_buffer------------------------------------
1161 void PhaseOutput::estimate_buffer_size(int& const_req) {
1162
1163 // Set the initially allocated size
1164 const_req = initial_const_capacity;
1165
1166 // The extra spacing after the code is necessary on some platforms.
1167 // Sometimes we need to patch in a jump after the last instruction,
1168 // if the nmethod has been deoptimized. (See 4932387, 4894843.)
1169
1170 // Compute the byte offset where we can store the deopt pc.
1171 if (C->fixed_slots() != 0) {
1172 _orig_pc_slot_offset_in_bytes = C->regalloc()->reg2offset(OptoReg::stack2reg(_orig_pc_slot));
1173 }
1174
1175 // Compute prolog code size
1176 _method_size = 0;
1177 _frame_slots = OptoReg::reg2stack(C->matcher()->_old_SP) + C->regalloc()->_framesize;
1178 #if defined(IA64) && !defined(AIX)
1179 if (save_argument_registers()) {
1180 // 4815101: this is a stub with implicit and unknown precision fp args.
1181 // The usual spill mechanism can only generate stfd's in this case, which
1182 // doesn't work if the fp reg to spill contains a single-precision denorm.
1183 // Instead, we hack around the normal spill mechanism using stfspill's and
1184 // ldffill's in the MachProlog and MachEpilog emit methods. We allocate
1185 // space here for the fp arg regs (f8-f15) we're going to thusly spill.
1186 //
1187 // If we ever implement 16-byte 'registers' == stack slots, we can
1188 // get rid of this hack and have SpillCopy generate stfspill/ldffill
1189 // instead of stfd/stfs/ldfd/ldfs.
1190 _frame_slots += 8*(16/BytesPerInt);
1191 }
1192 #endif
1193 assert(_frame_slots >= 0 && _frame_slots < 1000000, "sanity check");
1194
1195 if (C->has_mach_constant_base_node()) {
1196 uint add_size = 0;
1197 // Fill the constant table.
1198 // Note: This must happen before shorten_branches.
1199 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) {
1200 Block* b = C->cfg()->get_block(i);
1201
1202 for (uint j = 0; j < b->number_of_nodes(); j++) {
1203 Node* n = b->get_node(j);
1204
1205 // If the node is a MachConstantNode evaluate the constant
1206 // value section.
1207 if (n->is_MachConstant()) {
1208 MachConstantNode* machcon = n->as_MachConstant();
1209 machcon->eval_constant(C);
1210 } else if (n->is_Mach()) {
1211 // On Power there are more nodes that issue constants.
1212 add_size += (n->as_Mach()->ins_num_consts() * 8);
1213 }
1214 }
1215 }
1216
1217 // Calculate the offsets of the constants and the size of the
1218 // constant table (including the padding to the next section).
1219 constant_table().calculate_offsets_and_size();
1220 const_req = constant_table().size() + add_size;
1221 }
1222
1223 // Initialize the space for the BufferBlob used to find and verify
1224 // instruction size in MachNode::emit_size()
1225 init_scratch_buffer_blob(const_req);
1226 }
1227
1228 CodeBuffer* PhaseOutput::init_buffer() {
1229 int stub_req = _buf_sizes._stub;
1230 int code_req = _buf_sizes._code;
1231 int const_req = _buf_sizes._const;
1232
1233 int pad_req = NativeCall::instruction_size;
1234
1235 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1236 stub_req += bs->estimate_stub_size();
1237
1238 // nmethod and CodeBuffer count stubs & constants as part of method's code.
1239 // class HandlerImpl is platform-specific and defined in the *.ad files.
1240 int exception_handler_req = HandlerImpl::size_exception_handler() + MAX_stubs_size; // add marginal slop for handler
1241 int deopt_handler_req = HandlerImpl::size_deopt_handler() + MAX_stubs_size; // add marginal slop for handler
1242 stub_req += MAX_stubs_size; // ensure per-stub margin
1243 code_req += MAX_inst_size; // ensure per-instruction margin
1244
1245 if (StressCodeBuffers)
1246 code_req = const_req = stub_req = exception_handler_req = deopt_handler_req = 0x10; // force expansion
1247
1248 int total_req =
1249 const_req +
1250 code_req +
1251 pad_req +
1252 stub_req +
1253 exception_handler_req +
1254 deopt_handler_req; // deopt handler
1255
1256 if (C->has_method_handle_invokes())
1257 total_req += deopt_handler_req; // deopt MH handler
1258
1259 CodeBuffer* cb = code_buffer();
1260 cb->initialize(total_req, _buf_sizes._reloc);
1261
1262 // Have we run out of code space?
1263 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) {
1264 C->record_failure("CodeCache is full");
1265 return NULL;
1266 }
1267 // Configure the code buffer.
1268 cb->initialize_consts_size(const_req);
1269 cb->initialize_stubs_size(stub_req);
1270 cb->initialize_oop_recorder(C->env()->oop_recorder());
1271
1272 // fill in the nop array for bundling computations
1273 MachNode *_nop_list[Bundle::_nop_count];
1274 Bundle::initialize_nops(_nop_list);
1275
1276 return cb;
1277 }
1278
1279 //------------------------------fill_buffer------------------------------------
1280 void PhaseOutput::fill_buffer(CodeBuffer* cb, uint* blk_starts) {
1281 // blk_starts[] contains offsets calculated during short branches processing,
1282 // offsets should not be increased during following steps.
1283
1284 // Compute the size of first NumberOfLoopInstrToAlign instructions at head
1285 // of a loop. It is used to determine the padding for loop alignment.
1286 compute_loop_first_inst_sizes();
1287
1288 // Create oopmap set.
1289 _oop_map_set = new OopMapSet();
1290
1291 // !!!!! This preserves old handling of oopmaps for now
1292 C->debug_info()->set_oopmaps(_oop_map_set);
1293
1294 uint nblocks = C->cfg()->number_of_blocks();
1295 // Count and start of implicit null check instructions
1296 uint inct_cnt = 0;
1297 uint *inct_starts = NEW_RESOURCE_ARRAY(uint, nblocks+1);
1298
1299 // Count and start of calls
1300 uint *call_returns = NEW_RESOURCE_ARRAY(uint, nblocks+1);
1301
1302 uint return_offset = 0;
1303 int nop_size = (new MachNopNode())->size(C->regalloc());
1304
1305 int previous_offset = 0;
1306 int current_offset = 0;
1307 int last_call_offset = -1;
1308 int last_avoid_back_to_back_offset = -1;
1309 #ifdef ASSERT
1310 uint* jmp_target = NEW_RESOURCE_ARRAY(uint,nblocks);
1311 uint* jmp_offset = NEW_RESOURCE_ARRAY(uint,nblocks);
1312 uint* jmp_size = NEW_RESOURCE_ARRAY(uint,nblocks);
1313 uint* jmp_rule = NEW_RESOURCE_ARRAY(uint,nblocks);
1314 #endif
1315
1316 // Create an array of unused labels, one for each basic block, if printing is enabled
1317 #if defined(SUPPORT_OPTO_ASSEMBLY)
1318 int *node_offsets = NULL;
1319 uint node_offset_limit = C->unique();
1320
1321 if (C->print_assembly()) {
1322 node_offsets = NEW_RESOURCE_ARRAY(int, node_offset_limit);
1323 }
1324 if (node_offsets != NULL) {
1325 // We need to initialize. Unused array elements may contain garbage and mess up PrintOptoAssembly.
1326 memset(node_offsets, 0, node_offset_limit*sizeof(int));
1327 }
1328 #endif
1329
1330 NonSafepointEmitter non_safepoints(C); // emit non-safepoints lazily
1331
1332 // Emit the constant table.
1333 if (C->has_mach_constant_base_node()) {
1334 constant_table().emit(*cb);
1335 }
1336
1337 // Create an array of labels, one for each basic block
1338 Label *blk_labels = NEW_RESOURCE_ARRAY(Label, nblocks+1);
1339 for (uint i=0; i <= nblocks; i++) {
1340 blk_labels[i].init();
1341 }
1342
1343 // ------------------
1344 // Now fill in the code buffer
1345 Node *delay_slot = NULL;
1346
1347 for (uint i = 0; i < nblocks; i++) {
1348 Block* block = C->cfg()->get_block(i);
1349 _block = block;
1350 Node* head = block->head();
1351
1352 // If this block needs to start aligned (i.e, can be reached other
1353 // than by falling-thru from the previous block), then force the
1354 // start of a new bundle.
1355 if (Pipeline::requires_bundling() && starts_bundle(head)) {
1356 cb->flush_bundle(true);
1357 }
1358
1359 #ifdef ASSERT
1360 if (!block->is_connector()) {
1361 stringStream st;
1362 block->dump_head(C->cfg(), &st);
1363 MacroAssembler(cb).block_comment(st.as_string());
1364 }
1365 jmp_target[i] = 0;
1366 jmp_offset[i] = 0;
1367 jmp_size[i] = 0;
1368 jmp_rule[i] = 0;
1369 #endif
1370 int blk_offset = current_offset;
1371
1372 // Define the label at the beginning of the basic block
1373 MacroAssembler(cb).bind(blk_labels[block->_pre_order]);
1374
1375 uint last_inst = block->number_of_nodes();
1376
1377 // Emit block normally, except for last instruction.
1378 // Emit means "dump code bits into code buffer".
1379 for (uint j = 0; j<last_inst; j++) {
1380 _index = j;
1381
1382 // Get the node
1383 Node* n = block->get_node(j);
1384
1385 // See if delay slots are supported
1386 if (valid_bundle_info(n) && node_bundling(n)->used_in_unconditional_delay()) {
1387 assert(delay_slot == NULL, "no use of delay slot node");
1388 assert(n->size(C->regalloc()) == Pipeline::instr_unit_size(), "delay slot instruction wrong size");
1389
1390 delay_slot = n;
1391 continue;
1392 }
1393
1394 // If this starts a new instruction group, then flush the current one
1395 // (but allow split bundles)
1396 if (Pipeline::requires_bundling() && starts_bundle(n))
1397 cb->flush_bundle(false);
1398
1399 // Special handling for SafePoint/Call Nodes
1400 bool is_mcall = false;
1401 if (n->is_Mach()) {
1402 MachNode *mach = n->as_Mach();
1403 is_mcall = n->is_MachCall();
1404 bool is_sfn = n->is_MachSafePoint();
1405
1406 // If this requires all previous instructions be flushed, then do so
1407 if (is_sfn || is_mcall || mach->alignment_required() != 1) {
1408 cb->flush_bundle(true);
1409 current_offset = cb->insts_size();
1410 }
1411
1412 // A padding may be needed again since a previous instruction
1413 // could be moved to delay slot.
1414
1415 // align the instruction if necessary
1416 int padding = mach->compute_padding(current_offset);
1417 // Make sure safepoint node for polling is distinct from a call's
1418 // return by adding a nop if needed.
1419 if (is_sfn && !is_mcall && padding == 0 && current_offset == last_call_offset) {
1420 padding = nop_size;
1421 }
1422 if (padding == 0 && mach->avoid_back_to_back(MachNode::AVOID_BEFORE) &&
1423 current_offset == last_avoid_back_to_back_offset) {
1424 // Avoid back to back some instructions.
1425 padding = nop_size;
1426 }
1427
1428 if (padding > 0) {
1429 assert((padding % nop_size) == 0, "padding is not a multiple of NOP size");
1430 int nops_cnt = padding / nop_size;
1431 MachNode *nop = new MachNopNode(nops_cnt);
1432 block->insert_node(nop, j++);
1433 last_inst++;
1434 C->cfg()->map_node_to_block(nop, block);
1435 // Ensure enough space.
1436 cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size);
1437 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) {
1438 C->record_failure("CodeCache is full");
1439 return;
1440 }
1441 nop->emit(*cb, C->regalloc());
1442 cb->flush_bundle(true);
1443 current_offset = cb->insts_size();
1444 }
1445
1446 // Remember the start of the last call in a basic block
1447 if (is_mcall) {
1448 MachCallNode *mcall = mach->as_MachCall();
1449
1450 // This destination address is NOT PC-relative
1451 mcall->method_set((intptr_t)mcall->entry_point());
1452
1453 // Save the return address
1454 call_returns[block->_pre_order] = current_offset + mcall->ret_addr_offset();
1455
1456 if (mcall->is_MachCallLeaf()) {
1457 is_mcall = false;
1458 is_sfn = false;
1459 }
1460 }
1461
1462 // sfn will be valid whenever mcall is valid now because of inheritance
1463 if (is_sfn || is_mcall) {
1464
1465 // Handle special safepoint nodes for synchronization
1466 if (!is_mcall) {
1467 MachSafePointNode *sfn = mach->as_MachSafePoint();
1468 // !!!!! Stubs only need an oopmap right now, so bail out
1469 if (sfn->jvms()->method() == NULL) {
1470 // Write the oopmap directly to the code blob??!!
1471 continue;
1472 }
1473 } // End synchronization
1474
1475 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(),
1476 current_offset);
1477 Process_OopMap_Node(mach, current_offset);
1478 } // End if safepoint
1479
1480 // If this is a null check, then add the start of the previous instruction to the list
1481 else if( mach->is_MachNullCheck() ) {
1482 inct_starts[inct_cnt++] = previous_offset;
1483 }
1484
1485 // If this is a branch, then fill in the label with the target BB's label
1486 else if (mach->is_MachBranch()) {
1487 // This requires the TRUE branch target be in succs[0]
1488 uint block_num = block->non_connector_successor(0)->_pre_order;
1489
1490 // Try to replace long branch if delay slot is not used,
1491 // it is mostly for back branches since forward branch's
1492 // distance is not updated yet.
1493 bool delay_slot_is_used = valid_bundle_info(n) &&
1494 C->output()->node_bundling(n)->use_unconditional_delay();
1495 if (!delay_slot_is_used && mach->may_be_short_branch()) {
1496 assert(delay_slot == NULL, "not expecting delay slot node");
1497 int br_size = n->size(C->regalloc());
1498 int offset = blk_starts[block_num] - current_offset;
1499 if (block_num >= i) {
1500 // Current and following block's offset are not
1501 // finalized yet, adjust distance by the difference
1502 // between calculated and final offsets of current block.
1503 offset -= (blk_starts[i] - blk_offset);
1504 }
1505 // In the following code a nop could be inserted before
1506 // the branch which will increase the backward distance.
1507 bool needs_padding = (current_offset == last_avoid_back_to_back_offset);
1508 if (needs_padding && offset <= 0)
1509 offset -= nop_size;
1510
1511 if (C->matcher()->is_short_branch_offset(mach->rule(), br_size, offset)) {
1512 // We've got a winner. Replace this branch.
1513 MachNode* replacement = mach->as_MachBranch()->short_branch_version();
1514
1515 // Update the jmp_size.
1516 int new_size = replacement->size(C->regalloc());
1517 assert((br_size - new_size) >= (int)nop_size, "short_branch size should be smaller");
1518 // Insert padding between avoid_back_to_back branches.
1519 if (needs_padding && replacement->avoid_back_to_back(MachNode::AVOID_BEFORE)) {
1520 MachNode *nop = new MachNopNode();
1521 block->insert_node(nop, j++);
1522 C->cfg()->map_node_to_block(nop, block);
1523 last_inst++;
1524 nop->emit(*cb, C->regalloc());
1525 cb->flush_bundle(true);
1526 current_offset = cb->insts_size();
1527 }
1528 #ifdef ASSERT
1529 jmp_target[i] = block_num;
1530 jmp_offset[i] = current_offset - blk_offset;
1531 jmp_size[i] = new_size;
1532 jmp_rule[i] = mach->rule();
1533 #endif
1534 block->map_node(replacement, j);
1535 mach->subsume_by(replacement, C);
1536 n = replacement;
1537 mach = replacement;
1538 }
1539 }
1540 mach->as_MachBranch()->label_set( &blk_labels[block_num], block_num );
1541 } else if (mach->ideal_Opcode() == Op_Jump) {
1542 for (uint h = 0; h < block->_num_succs; h++) {
1543 Block* succs_block = block->_succs[h];
1544 for (uint j = 1; j < succs_block->num_preds(); j++) {
1545 Node* jpn = succs_block->pred(j);
1546 if (jpn->is_JumpProj() && jpn->in(0) == mach) {
1547 uint block_num = succs_block->non_connector()->_pre_order;
1548 Label *blkLabel = &blk_labels[block_num];
1549 mach->add_case_label(jpn->as_JumpProj()->proj_no(), blkLabel);
1550 }
1551 }
1552 }
1553 }
1554 #ifdef ASSERT
1555 // Check that oop-store precedes the card-mark
1556 else if (mach->ideal_Opcode() == Op_StoreCM) {
1557 uint storeCM_idx = j;
1558 int count = 0;
1559 for (uint prec = mach->req(); prec < mach->len(); prec++) {
1560 Node *oop_store = mach->in(prec); // Precedence edge
1561 if (oop_store == NULL) continue;
1562 count++;
1563 uint i4;
1564 for (i4 = 0; i4 < last_inst; ++i4) {
1565 if (block->get_node(i4) == oop_store) {
1566 break;
1567 }
1568 }
1569 // Note: This test can provide a false failure if other precedence
1570 // edges have been added to the storeCMNode.
1571 assert(i4 == last_inst || i4 < storeCM_idx, "CM card-mark executes before oop-store");
1572 }
1573 assert(count > 0, "storeCM expects at least one precedence edge");
1574 }
1575 #endif
1576 else if (!n->is_Proj()) {
1577 // Remember the beginning of the previous instruction, in case
1578 // it's followed by a flag-kill and a null-check. Happens on
1579 // Intel all the time, with add-to-memory kind of opcodes.
1580 previous_offset = current_offset;
1581 }
1582
1583 // Not an else-if!
1584 // If this is a trap based cmp then add its offset to the list.
1585 if (mach->is_TrapBasedCheckNode()) {
1586 inct_starts[inct_cnt++] = current_offset;
1587 }
1588 }
1589
1590 // Verify that there is sufficient space remaining
1591 cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size);
1592 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) {
1593 C->record_failure("CodeCache is full");
1594 return;
1595 }
1596
1597 // Save the offset for the listing
1598 #if defined(SUPPORT_OPTO_ASSEMBLY)
1599 if ((node_offsets != NULL) && (n->_idx < node_offset_limit)) {
1600 node_offsets[n->_idx] = cb->insts_size();
1601 }
1602 #endif
1603
1604 // "Normal" instruction case
1605 DEBUG_ONLY( uint instr_offset = cb->insts_size(); )
1606 n->emit(*cb, C->regalloc());
1607 current_offset = cb->insts_size();
1608
1609 // Above we only verified that there is enough space in the instruction section.
1610 // However, the instruction may emit stubs that cause code buffer expansion.
1611 // Bail out here if expansion failed due to a lack of code cache space.
1612 if (C->failing()) {
1613 return;
1614 }
1615
1616 #ifdef ASSERT
1617 if (n->size(C->regalloc()) < (current_offset-instr_offset)) {
1618 n->dump();
1619 assert(false, "wrong size of mach node");
1620 }
1621 #endif
1622 non_safepoints.observe_instruction(n, current_offset);
1623
1624 // mcall is last "call" that can be a safepoint
1625 // record it so we can see if a poll will directly follow it
1626 // in which case we'll need a pad to make the PcDesc sites unique
1627 // see 5010568. This can be slightly inaccurate but conservative
1628 // in the case that return address is not actually at current_offset.
1629 // This is a small price to pay.
1630
1631 if (is_mcall) {
1632 last_call_offset = current_offset;
1633 }
1634
1635 if (n->is_Mach() && n->as_Mach()->avoid_back_to_back(MachNode::AVOID_AFTER)) {
1636 // Avoid back to back some instructions.
1637 last_avoid_back_to_back_offset = current_offset;
1638 }
1639
1640 // See if this instruction has a delay slot
1641 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
1642 guarantee(delay_slot != NULL, "expecting delay slot node");
1643
1644 // Back up 1 instruction
1645 cb->set_insts_end(cb->insts_end() - Pipeline::instr_unit_size());
1646
1647 // Save the offset for the listing
1648 #if defined(SUPPORT_OPTO_ASSEMBLY)
1649 if ((node_offsets != NULL) && (delay_slot->_idx < node_offset_limit)) {
1650 node_offsets[delay_slot->_idx] = cb->insts_size();
1651 }
1652 #endif
1653
1654 // Support a SafePoint in the delay slot
1655 if (delay_slot->is_MachSafePoint()) {
1656 MachNode *mach = delay_slot->as_Mach();
1657 // !!!!! Stubs only need an oopmap right now, so bail out
1658 if (!mach->is_MachCall() && mach->as_MachSafePoint()->jvms()->method() == NULL) {
1659 // Write the oopmap directly to the code blob??!!
1660 delay_slot = NULL;
1661 continue;
1662 }
1663
1664 int adjusted_offset = current_offset - Pipeline::instr_unit_size();
1665 non_safepoints.observe_safepoint(mach->as_MachSafePoint()->jvms(),
1666 adjusted_offset);
1667 // Generate an OopMap entry
1668 Process_OopMap_Node(mach, adjusted_offset);
1669 }
1670
1671 // Insert the delay slot instruction
1672 delay_slot->emit(*cb, C->regalloc());
1673
1674 // Don't reuse it
1675 delay_slot = NULL;
1676 }
1677
1678 } // End for all instructions in block
1679
1680 // If the next block is the top of a loop, pad this block out to align
1681 // the loop top a little. Helps prevent pipe stalls at loop back branches.
1682 if (i < nblocks-1) {
1683 Block *nb = C->cfg()->get_block(i + 1);
1684 int padding = nb->alignment_padding(current_offset);
1685 if( padding > 0 ) {
1686 MachNode *nop = new MachNopNode(padding / nop_size);
1687 block->insert_node(nop, block->number_of_nodes());
1688 C->cfg()->map_node_to_block(nop, block);
1689 nop->emit(*cb, C->regalloc());
1690 current_offset = cb->insts_size();
1691 }
1692 }
1693 // Verify that the distance for generated before forward
1694 // short branches is still valid.
1695 guarantee((int)(blk_starts[i+1] - blk_starts[i]) >= (current_offset - blk_offset), "shouldn't increase block size");
1696
1697 // Save new block start offset
1698 blk_starts[i] = blk_offset;
1699 } // End of for all blocks
1700 blk_starts[nblocks] = current_offset;
1701
1702 non_safepoints.flush_at_end();
1703
1704 // Offset too large?
1705 if (C->failing()) return;
1706
1707 // Define a pseudo-label at the end of the code
1708 MacroAssembler(cb).bind( blk_labels[nblocks] );
1709
1710 // Compute the size of the first block
1711 _first_block_size = blk_labels[1].loc_pos() - blk_labels[0].loc_pos();
1712
1713 #ifdef ASSERT
1714 for (uint i = 0; i < nblocks; i++) { // For all blocks
1715 if (jmp_target[i] != 0) {
1716 int br_size = jmp_size[i];
1717 int offset = blk_starts[jmp_target[i]]-(blk_starts[i] + jmp_offset[i]);
1718 if (!C->matcher()->is_short_branch_offset(jmp_rule[i], br_size, offset)) {
1719 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]);
1720 assert(false, "Displacement too large for short jmp");
1721 }
1722 }
1723 }
1724 #endif
1725
1726 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1727 bs->emit_stubs(*cb);
1728 if (C->failing()) return;
1729
1730 #ifndef PRODUCT
1731 // Information on the size of the method, without the extraneous code
1732 Scheduling::increment_method_size(cb->insts_size());
1733 #endif
1734
1735 // ------------------
1736 // Fill in exception table entries.
1737 FillExceptionTables(inct_cnt, call_returns, inct_starts, blk_labels);
1738
1739 // Only java methods have exception handlers and deopt handlers
1740 // class HandlerImpl is platform-specific and defined in the *.ad files.
1741 if (C->method()) {
1742 // Emit the exception handler code.
1743 _code_offsets.set_value(CodeOffsets::Exceptions, HandlerImpl::emit_exception_handler(*cb));
1744 if (C->failing()) {
1745 return; // CodeBuffer::expand failed
1746 }
1747 // Emit the deopt handler code.
1748 _code_offsets.set_value(CodeOffsets::Deopt, HandlerImpl::emit_deopt_handler(*cb));
1749
1750 // Emit the MethodHandle deopt handler code (if required).
1751 if (C->has_method_handle_invokes() && !C->failing()) {
1752 // We can use the same code as for the normal deopt handler, we
1753 // just need a different entry point address.
1754 _code_offsets.set_value(CodeOffsets::DeoptMH, HandlerImpl::emit_deopt_handler(*cb));
1755 }
1756 }
1757
1758 // One last check for failed CodeBuffer::expand:
1759 if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) {
1760 C->record_failure("CodeCache is full");
1761 return;
1762 }
1763
1764 #if defined(SUPPORT_ABSTRACT_ASSEMBLY) || defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_OPTO_ASSEMBLY)
1765 if (C->print_assembly()) {
1766 tty->cr();
1767 tty->print_cr("============================= C2-compiled nmethod ==============================");
1768 }
1769 #endif
1770
1771 #if defined(SUPPORT_OPTO_ASSEMBLY)
1772 // Dump the assembly code, including basic-block numbers
1773 if (C->print_assembly()) {
1774 ttyLocker ttyl; // keep the following output all in one block
1775 if (!VMThread::should_terminate()) { // test this under the tty lock
1776 // This output goes directly to the tty, not the compiler log.
1777 // To enable tools to match it up with the compilation activity,
1778 // be sure to tag this tty output with the compile ID.
1779 if (xtty != NULL) {
1780 xtty->head("opto_assembly compile_id='%d'%s", C->compile_id(),
1781 C->is_osr_compilation() ? " compile_kind='osr'" :
1782 "");
1783 }
1784 if (C->method() != NULL) {
1785 tty->print_cr("----------------------- MetaData before Compile_id = %d ------------------------", C->compile_id());
1786 C->method()->print_metadata();
1787 } else if (C->stub_name() != NULL) {
1788 tty->print_cr("----------------------------- RuntimeStub %s -------------------------------", C->stub_name());
1789 }
1790 tty->cr();
1791 tty->print_cr("------------------------ OptoAssembly for Compile_id = %d -----------------------", C->compile_id());
1792 dump_asm(node_offsets, node_offset_limit);
1793 tty->print_cr("--------------------------------------------------------------------------------");
1794 if (xtty != NULL) {
1795 // print_metadata and dump_asm above may safepoint which makes us loose the ttylock.
1796 // Retake lock too make sure the end tag is coherent, and that xmlStream->pop_tag is done
1797 // thread safe
1798 ttyLocker ttyl2;
1799 xtty->tail("opto_assembly");
1800 }
1801 }
1802 }
1803 #endif
1804 }
1805
1806 void PhaseOutput::FillExceptionTables(uint cnt, uint *call_returns, uint *inct_starts, Label *blk_labels) {
1807 _inc_table.set_size(cnt);
1808
1809 uint inct_cnt = 0;
1810 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) {
1811 Block* block = C->cfg()->get_block(i);
1812 Node *n = NULL;
1813 int j;
1814
1815 // Find the branch; ignore trailing NOPs.
1816 for (j = block->number_of_nodes() - 1; j >= 0; j--) {
1817 n = block->get_node(j);
1818 if (!n->is_Mach() || n->as_Mach()->ideal_Opcode() != Op_Con) {
1819 break;
1820 }
1821 }
1822
1823 // If we didn't find anything, continue
1824 if (j < 0) {
1825 continue;
1826 }
1827
1828 // Compute ExceptionHandlerTable subtable entry and add it
1829 // (skip empty blocks)
1830 if (n->is_Catch()) {
1831
1832 // Get the offset of the return from the call
1833 uint call_return = call_returns[block->_pre_order];
1834 #ifdef ASSERT
1835 assert( call_return > 0, "no call seen for this basic block" );
1836 while (block->get_node(--j)->is_MachProj()) ;
1837 assert(block->get_node(j)->is_MachCall(), "CatchProj must follow call");
1838 #endif
1839 // last instruction is a CatchNode, find it's CatchProjNodes
1840 int nof_succs = block->_num_succs;
1841 // allocate space
1842 GrowableArray<intptr_t> handler_bcis(nof_succs);
1843 GrowableArray<intptr_t> handler_pcos(nof_succs);
1844 // iterate through all successors
1845 for (int j = 0; j < nof_succs; j++) {
1846 Block* s = block->_succs[j];
1847 bool found_p = false;
1848 for (uint k = 1; k < s->num_preds(); k++) {
1849 Node* pk = s->pred(k);
1850 if (pk->is_CatchProj() && pk->in(0) == n) {
1851 const CatchProjNode* p = pk->as_CatchProj();
1852 found_p = true;
1853 // add the corresponding handler bci & pco information
1854 if (p->_con != CatchProjNode::fall_through_index) {
1855 // p leads to an exception handler (and is not fall through)
1856 assert(s == C->cfg()->get_block(s->_pre_order), "bad numbering");
1857 // no duplicates, please
1858 if (!handler_bcis.contains(p->handler_bci())) {
1859 uint block_num = s->non_connector()->_pre_order;
1860 handler_bcis.append(p->handler_bci());
1861 handler_pcos.append(blk_labels[block_num].loc_pos());
1862 }
1863 }
1864 }
1865 }
1866 assert(found_p, "no matching predecessor found");
1867 // Note: Due to empty block removal, one block may have
1868 // several CatchProj inputs, from the same Catch.
1869 }
1870
1871 // Set the offset of the return from the call
1872 assert(handler_bcis.find(-1) != -1, "must have default handler");
1873 _handler_table.add_subtable(call_return, &handler_bcis, NULL, &handler_pcos);
1874 continue;
1875 }
1876
1877 // Handle implicit null exception table updates
1878 if (n->is_MachNullCheck()) {
1879 uint block_num = block->non_connector_successor(0)->_pre_order;
1880 _inc_table.append(inct_starts[inct_cnt++], blk_labels[block_num].loc_pos());
1881 continue;
1882 }
1883 // Handle implicit exception table updates: trap instructions.
1884 if (n->is_Mach() && n->as_Mach()->is_TrapBasedCheckNode()) {
1885 uint block_num = block->non_connector_successor(0)->_pre_order;
1886 _inc_table.append(inct_starts[inct_cnt++], blk_labels[block_num].loc_pos());
1887 continue;
1888 }
1889 } // End of for all blocks fill in exception table entries
1890 }
1891
1892 // Static Variables
1893 #ifndef PRODUCT
1894 uint Scheduling::_total_nop_size = 0;
1895 uint Scheduling::_total_method_size = 0;
1896 uint Scheduling::_total_branches = 0;
1897 uint Scheduling::_total_unconditional_delays = 0;
1898 uint Scheduling::_total_instructions_per_bundle[Pipeline::_max_instrs_per_cycle+1];
1899 #endif
1900
1901 // Initializer for class Scheduling
1902
1903 Scheduling::Scheduling(Arena *arena, Compile &compile)
1904 : _arena(arena),
1905 _cfg(compile.cfg()),
1906 _regalloc(compile.regalloc()),
1907 _scheduled(arena),
1908 _available(arena),
1909 _reg_node(arena),
1910 _pinch_free_list(arena),
1911 _next_node(NULL),
1912 _bundle_instr_count(0),
1913 _bundle_cycle_number(0),
1914 _bundle_use(0, 0, resource_count, &_bundle_use_elements[0])
1915 #ifndef PRODUCT
1916 , _branches(0)
1917 , _unconditional_delays(0)
1918 #endif
1919 {
1920 // Create a MachNopNode
1921 _nop = new MachNopNode();
1922
1923 // Now that the nops are in the array, save the count
1924 // (but allow entries for the nops)
1925 _node_bundling_limit = compile.unique();
1926 uint node_max = _regalloc->node_regs_max_index();
1927
1928 compile.output()->set_node_bundling_limit(_node_bundling_limit);
1929
1930 // This one is persistent within the Compile class
1931 _node_bundling_base = NEW_ARENA_ARRAY(compile.comp_arena(), Bundle, node_max);
1932
1933 // Allocate space for fixed-size arrays
1934 _node_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max);
1935 _uses = NEW_ARENA_ARRAY(arena, short, node_max);
1936 _current_latency = NEW_ARENA_ARRAY(arena, unsigned short, node_max);
1937
1938 // Clear the arrays
1939 for (uint i = 0; i < node_max; i++) {
1940 ::new (&_node_bundling_base[i]) Bundle();
1941 }
1942 memset(_node_latency, 0, node_max * sizeof(unsigned short));
1943 memset(_uses, 0, node_max * sizeof(short));
1944 memset(_current_latency, 0, node_max * sizeof(unsigned short));
1945
1946 // Clear the bundling information
1947 memcpy(_bundle_use_elements, Pipeline_Use::elaborated_elements, sizeof(Pipeline_Use::elaborated_elements));
1948
1949 // Get the last node
1950 Block* block = _cfg->get_block(_cfg->number_of_blocks() - 1);
1951
1952 _next_node = block->get_node(block->number_of_nodes() - 1);
1953 }
1954
1955 #ifndef PRODUCT
1956 // Scheduling destructor
1957 Scheduling::~Scheduling() {
1958 _total_branches += _branches;
1959 _total_unconditional_delays += _unconditional_delays;
1960 }
1961 #endif
1962
1963 // Step ahead "i" cycles
1964 void Scheduling::step(uint i) {
1965
1966 Bundle *bundle = node_bundling(_next_node);
1967 bundle->set_starts_bundle();
1968
1969 // Update the bundle record, but leave the flags information alone
1970 if (_bundle_instr_count > 0) {
1971 bundle->set_instr_count(_bundle_instr_count);
1972 bundle->set_resources_used(_bundle_use.resourcesUsed());
1973 }
1974
1975 // Update the state information
1976 _bundle_instr_count = 0;
1977 _bundle_cycle_number += i;
1978 _bundle_use.step(i);
1979 }
1980
1981 void Scheduling::step_and_clear() {
1982 Bundle *bundle = node_bundling(_next_node);
1983 bundle->set_starts_bundle();
1984
1985 // Update the bundle record
1986 if (_bundle_instr_count > 0) {
1987 bundle->set_instr_count(_bundle_instr_count);
1988 bundle->set_resources_used(_bundle_use.resourcesUsed());
1989
1990 _bundle_cycle_number += 1;
1991 }
1992
1993 // Clear the bundling information
1994 _bundle_instr_count = 0;
1995 _bundle_use.reset();
1996
1997 memcpy(_bundle_use_elements,
1998 Pipeline_Use::elaborated_elements,
1999 sizeof(Pipeline_Use::elaborated_elements));
2000 }
2001
2002 // Perform instruction scheduling and bundling over the sequence of
2003 // instructions in backwards order.
2004 void PhaseOutput::ScheduleAndBundle() {
2005
2006 // Don't optimize this if it isn't a method
2007 if (!C->method())
2008 return;
2009
2010 // Don't optimize this if scheduling is disabled
2011 if (!C->do_scheduling())
2012 return;
2013
2014 // Scheduling code works only with pairs (16 bytes) maximum.
2015 if (C->max_vector_size() > 16)
2016 return;
2017
2018 Compile::TracePhase tp("isched", &timers[_t_instrSched]);
2019
2020 // Create a data structure for all the scheduling information
2021 Scheduling scheduling(Thread::current()->resource_area(), *C);
2022
2023 // Walk backwards over each basic block, computing the needed alignment
2024 // Walk over all the basic blocks
2025 scheduling.DoScheduling();
2026
2027 #ifndef PRODUCT
2028 if (C->trace_opto_output()) {
2029 tty->print("\n---- After ScheduleAndBundle ----\n");
2030 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) {
2031 tty->print("\nBB#%03d:\n", i);
2032 Block* block = C->cfg()->get_block(i);
2033 for (uint j = 0; j < block->number_of_nodes(); j++) {
2034 Node* n = block->get_node(j);
2035 OptoReg::Name reg = C->regalloc()->get_reg_first(n);
2036 tty->print(" %-6s ", reg >= 0 && reg < REG_COUNT ? Matcher::regName[reg] : "");
2037 n->dump();
2038 }
2039 }
2040 }
2041 #endif
2042 }
2043
2044 // Compute the latency of all the instructions. This is fairly simple,
2045 // because we already have a legal ordering. Walk over the instructions
2046 // from first to last, and compute the latency of the instruction based
2047 // on the latency of the preceding instruction(s).
2048 void Scheduling::ComputeLocalLatenciesForward(const Block *bb) {
2049 #ifndef PRODUCT
2050 if (_cfg->C->trace_opto_output())
2051 tty->print("# -> ComputeLocalLatenciesForward\n");
2052 #endif
2053
2054 // Walk over all the schedulable instructions
2055 for( uint j=_bb_start; j < _bb_end; j++ ) {
2056
2057 // This is a kludge, forcing all latency calculations to start at 1.
2058 // Used to allow latency 0 to force an instruction to the beginning
2059 // of the bb
2060 uint latency = 1;
2061 Node *use = bb->get_node(j);
2062 uint nlen = use->len();
2063
2064 // Walk over all the inputs
2065 for ( uint k=0; k < nlen; k++ ) {
2066 Node *def = use->in(k);
2067 if (!def)
2068 continue;
2069
2070 uint l = _node_latency[def->_idx] + use->latency(k);
2071 if (latency < l)
2072 latency = l;
2073 }
2074
2075 _node_latency[use->_idx] = latency;
2076
2077 #ifndef PRODUCT
2078 if (_cfg->C->trace_opto_output()) {
2079 tty->print("# latency %4d: ", latency);
2080 use->dump();
2081 }
2082 #endif
2083 }
2084
2085 #ifndef PRODUCT
2086 if (_cfg->C->trace_opto_output())
2087 tty->print("# <- ComputeLocalLatenciesForward\n");
2088 #endif
2089
2090 } // end ComputeLocalLatenciesForward
2091
2092 // See if this node fits into the present instruction bundle
2093 bool Scheduling::NodeFitsInBundle(Node *n) {
2094 uint n_idx = n->_idx;
2095
2096 // If this is the unconditional delay instruction, then it fits
2097 if (n == _unconditional_delay_slot) {
2098 #ifndef PRODUCT
2099 if (_cfg->C->trace_opto_output())
2100 tty->print("# NodeFitsInBundle [%4d]: TRUE; is in unconditional delay slot\n", n->_idx);
2101 #endif
2102 return (true);
2103 }
2104
2105 // If the node cannot be scheduled this cycle, skip it
2106 if (_current_latency[n_idx] > _bundle_cycle_number) {
2107 #ifndef PRODUCT
2108 if (_cfg->C->trace_opto_output())
2109 tty->print("# NodeFitsInBundle [%4d]: FALSE; latency %4d > %d\n",
2110 n->_idx, _current_latency[n_idx], _bundle_cycle_number);
2111 #endif
2112 return (false);
2113 }
2114
2115 const Pipeline *node_pipeline = n->pipeline();
2116
2117 uint instruction_count = node_pipeline->instructionCount();
2118 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0)
2119 instruction_count = 0;
2120 else if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot)
2121 instruction_count++;
2122
2123 if (_bundle_instr_count + instruction_count > Pipeline::_max_instrs_per_cycle) {
2124 #ifndef PRODUCT
2125 if (_cfg->C->trace_opto_output())
2126 tty->print("# NodeFitsInBundle [%4d]: FALSE; too many instructions: %d > %d\n",
2127 n->_idx, _bundle_instr_count + instruction_count, Pipeline::_max_instrs_per_cycle);
2128 #endif
2129 return (false);
2130 }
2131
2132 // Don't allow non-machine nodes to be handled this way
2133 if (!n->is_Mach() && instruction_count == 0)
2134 return (false);
2135
2136 // See if there is any overlap
2137 uint delay = _bundle_use.full_latency(0, node_pipeline->resourceUse());
2138
2139 if (delay > 0) {
2140 #ifndef PRODUCT
2141 if (_cfg->C->trace_opto_output())
2142 tty->print("# NodeFitsInBundle [%4d]: FALSE; functional units overlap\n", n_idx);
2143 #endif
2144 return false;
2145 }
2146
2147 #ifndef PRODUCT
2148 if (_cfg->C->trace_opto_output())
2149 tty->print("# NodeFitsInBundle [%4d]: TRUE\n", n_idx);
2150 #endif
2151
2152 return true;
2153 }
2154
2155 Node * Scheduling::ChooseNodeToBundle() {
2156 uint siz = _available.size();
2157
2158 if (siz == 0) {
2159
2160 #ifndef PRODUCT
2161 if (_cfg->C->trace_opto_output())
2162 tty->print("# ChooseNodeToBundle: NULL\n");
2163 #endif
2164 return (NULL);
2165 }
2166
2167 // Fast path, if only 1 instruction in the bundle
2168 if (siz == 1) {
2169 #ifndef PRODUCT
2170 if (_cfg->C->trace_opto_output()) {
2171 tty->print("# ChooseNodeToBundle (only 1): ");
2172 _available[0]->dump();
2173 }
2174 #endif
2175 return (_available[0]);
2176 }
2177
2178 // Don't bother, if the bundle is already full
2179 if (_bundle_instr_count < Pipeline::_max_instrs_per_cycle) {
2180 for ( uint i = 0; i < siz; i++ ) {
2181 Node *n = _available[i];
2182
2183 // Skip projections, we'll handle them another way
2184 if (n->is_Proj())
2185 continue;
2186
2187 // This presupposed that instructions are inserted into the
2188 // available list in a legality order; i.e. instructions that
2189 // must be inserted first are at the head of the list
2190 if (NodeFitsInBundle(n)) {
2191 #ifndef PRODUCT
2192 if (_cfg->C->trace_opto_output()) {
2193 tty->print("# ChooseNodeToBundle: ");
2194 n->dump();
2195 }
2196 #endif
2197 return (n);
2198 }
2199 }
2200 }
2201
2202 // Nothing fits in this bundle, choose the highest priority
2203 #ifndef PRODUCT
2204 if (_cfg->C->trace_opto_output()) {
2205 tty->print("# ChooseNodeToBundle: ");
2206 _available[0]->dump();
2207 }
2208 #endif
2209
2210 return _available[0];
2211 }
2212
2213 void Scheduling::AddNodeToAvailableList(Node *n) {
2214 assert( !n->is_Proj(), "projections never directly made available" );
2215 #ifndef PRODUCT
2216 if (_cfg->C->trace_opto_output()) {
2217 tty->print("# AddNodeToAvailableList: ");
2218 n->dump();
2219 }
2220 #endif
2221
2222 int latency = _current_latency[n->_idx];
2223
2224 // Insert in latency order (insertion sort)
2225 uint i;
2226 for ( i=0; i < _available.size(); i++ )
2227 if (_current_latency[_available[i]->_idx] > latency)
2228 break;
2229
2230 // Special Check for compares following branches
2231 if( n->is_Mach() && _scheduled.size() > 0 ) {
2232 int op = n->as_Mach()->ideal_Opcode();
2233 Node *last = _scheduled[0];
2234 if( last->is_MachIf() && last->in(1) == n &&
2235 ( op == Op_CmpI ||
2236 op == Op_CmpU ||
2237 op == Op_CmpUL ||
2238 op == Op_CmpP ||
2239 op == Op_CmpF ||
2240 op == Op_CmpD ||
2241 op == Op_CmpL ) ) {
2242
2243 // Recalculate position, moving to front of same latency
2244 for ( i=0 ; i < _available.size(); i++ )
2245 if (_current_latency[_available[i]->_idx] >= latency)
2246 break;
2247 }
2248 }
2249
2250 // Insert the node in the available list
2251 _available.insert(i, n);
2252
2253 #ifndef PRODUCT
2254 if (_cfg->C->trace_opto_output())
2255 dump_available();
2256 #endif
2257 }
2258
2259 void Scheduling::DecrementUseCounts(Node *n, const Block *bb) {
2260 for ( uint i=0; i < n->len(); i++ ) {
2261 Node *def = n->in(i);
2262 if (!def) continue;
2263 if( def->is_Proj() ) // If this is a machine projection, then
2264 def = def->in(0); // propagate usage thru to the base instruction
2265
2266 if(_cfg->get_block_for_node(def) != bb) { // Ignore if not block-local
2267 continue;
2268 }
2269
2270 // Compute the latency
2271 uint l = _bundle_cycle_number + n->latency(i);
2272 if (_current_latency[def->_idx] < l)
2273 _current_latency[def->_idx] = l;
2274
2275 // If this does not have uses then schedule it
2276 if ((--_uses[def->_idx]) == 0)
2277 AddNodeToAvailableList(def);
2278 }
2279 }
2280
2281 void Scheduling::AddNodeToBundle(Node *n, const Block *bb) {
2282 #ifndef PRODUCT
2283 if (_cfg->C->trace_opto_output()) {
2284 tty->print("# AddNodeToBundle: ");
2285 n->dump();
2286 }
2287 #endif
2288
2289 // Remove this from the available list
2290 uint i;
2291 for (i = 0; i < _available.size(); i++)
2292 if (_available[i] == n)
2293 break;
2294 assert(i < _available.size(), "entry in _available list not found");
2295 _available.remove(i);
2296
2297 // See if this fits in the current bundle
2298 const Pipeline *node_pipeline = n->pipeline();
2299 const Pipeline_Use& node_usage = node_pipeline->resourceUse();
2300
2301 // Check for instructions to be placed in the delay slot. We
2302 // do this before we actually schedule the current instruction,
2303 // because the delay slot follows the current instruction.
2304 if (Pipeline::_branch_has_delay_slot &&
2305 node_pipeline->hasBranchDelay() &&
2306 !_unconditional_delay_slot) {
2307
2308 uint siz = _available.size();
2309
2310 // Conditional branches can support an instruction that
2311 // is unconditionally executed and not dependent by the
2312 // branch, OR a conditionally executed instruction if
2313 // the branch is taken. In practice, this means that
2314 // the first instruction at the branch target is
2315 // copied to the delay slot, and the branch goes to
2316 // the instruction after that at the branch target
2317 if ( n->is_MachBranch() ) {
2318
2319 assert( !n->is_MachNullCheck(), "should not look for delay slot for Null Check" );
2320 assert( !n->is_Catch(), "should not look for delay slot for Catch" );
2321
2322 #ifndef PRODUCT
2323 _branches++;
2324 #endif
2325
2326 // At least 1 instruction is on the available list
2327 // that is not dependent on the branch
2328 for (uint i = 0; i < siz; i++) {
2329 Node *d = _available[i];
2330 const Pipeline *avail_pipeline = d->pipeline();
2331
2332 // Don't allow safepoints in the branch shadow, that will
2333 // cause a number of difficulties
2334 if ( avail_pipeline->instructionCount() == 1 &&
2335 !avail_pipeline->hasMultipleBundles() &&
2336 !avail_pipeline->hasBranchDelay() &&
2337 Pipeline::instr_has_unit_size() &&
2338 d->size(_regalloc) == Pipeline::instr_unit_size() &&
2339 NodeFitsInBundle(d) &&
2340 !node_bundling(d)->used_in_delay()) {
2341
2342 if (d->is_Mach() && !d->is_MachSafePoint()) {
2343 // A node that fits in the delay slot was found, so we need to
2344 // set the appropriate bits in the bundle pipeline information so
2345 // that it correctly indicates resource usage. Later, when we
2346 // attempt to add this instruction to the bundle, we will skip
2347 // setting the resource usage.
2348 _unconditional_delay_slot = d;
2349 node_bundling(n)->set_use_unconditional_delay();
2350 node_bundling(d)->set_used_in_unconditional_delay();
2351 _bundle_use.add_usage(avail_pipeline->resourceUse());
2352 _current_latency[d->_idx] = _bundle_cycle_number;
2353 _next_node = d;
2354 ++_bundle_instr_count;
2355 #ifndef PRODUCT
2356 _unconditional_delays++;
2357 #endif
2358 break;
2359 }
2360 }
2361 }
2362 }
2363
2364 // No delay slot, add a nop to the usage
2365 if (!_unconditional_delay_slot) {
2366 // See if adding an instruction in the delay slot will overflow
2367 // the bundle.
2368 if (!NodeFitsInBundle(_nop)) {
2369 #ifndef PRODUCT
2370 if (_cfg->C->trace_opto_output())
2371 tty->print("# *** STEP(1 instruction for delay slot) ***\n");
2372 #endif
2373 step(1);
2374 }
2375
2376 _bundle_use.add_usage(_nop->pipeline()->resourceUse());
2377 _next_node = _nop;
2378 ++_bundle_instr_count;
2379 }
2380
2381 // See if the instruction in the delay slot requires a
2382 // step of the bundles
2383 if (!NodeFitsInBundle(n)) {
2384 #ifndef PRODUCT
2385 if (_cfg->C->trace_opto_output())
2386 tty->print("# *** STEP(branch won't fit) ***\n");
2387 #endif
2388 // Update the state information
2389 _bundle_instr_count = 0;
2390 _bundle_cycle_number += 1;
2391 _bundle_use.step(1);
2392 }
2393 }
2394
2395 // Get the number of instructions
2396 uint instruction_count = node_pipeline->instructionCount();
2397 if (node_pipeline->mayHaveNoCode() && n->size(_regalloc) == 0)
2398 instruction_count = 0;
2399
2400 // Compute the latency information
2401 uint delay = 0;
2402
2403 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode()) {
2404 int relative_latency = _current_latency[n->_idx] - _bundle_cycle_number;
2405 if (relative_latency < 0)
2406 relative_latency = 0;
2407
2408 delay = _bundle_use.full_latency(relative_latency, node_usage);
2409
2410 // Does not fit in this bundle, start a new one
2411 if (delay > 0) {
2412 step(delay);
2413
2414 #ifndef PRODUCT
2415 if (_cfg->C->trace_opto_output())
2416 tty->print("# *** STEP(%d) ***\n", delay);
2417 #endif
2418 }
2419 }
2420
2421 // If this was placed in the delay slot, ignore it
2422 if (n != _unconditional_delay_slot) {
2423
2424 if (delay == 0) {
2425 if (node_pipeline->hasMultipleBundles()) {
2426 #ifndef PRODUCT
2427 if (_cfg->C->trace_opto_output())
2428 tty->print("# *** STEP(multiple instructions) ***\n");
2429 #endif
2430 step(1);
2431 }
2432
2433 else if (instruction_count + _bundle_instr_count > Pipeline::_max_instrs_per_cycle) {
2434 #ifndef PRODUCT
2435 if (_cfg->C->trace_opto_output())
2436 tty->print("# *** STEP(%d >= %d instructions) ***\n",
2437 instruction_count + _bundle_instr_count,
2438 Pipeline::_max_instrs_per_cycle);
2439 #endif
2440 step(1);
2441 }
2442 }
2443
2444 if (node_pipeline->hasBranchDelay() && !_unconditional_delay_slot)
2445 _bundle_instr_count++;
2446
2447 // Set the node's latency
2448 _current_latency[n->_idx] = _bundle_cycle_number;
2449
2450 // Now merge the functional unit information
2451 if (instruction_count > 0 || !node_pipeline->mayHaveNoCode())
2452 _bundle_use.add_usage(node_usage);
2453
2454 // Increment the number of instructions in this bundle
2455 _bundle_instr_count += instruction_count;
2456
2457 // Remember this node for later
2458 if (n->is_Mach())
2459 _next_node = n;
2460 }
2461
2462 // It's possible to have a BoxLock in the graph and in the _bbs mapping but
2463 // not in the bb->_nodes array. This happens for debug-info-only BoxLocks.
2464 // 'Schedule' them (basically ignore in the schedule) but do not insert them
2465 // into the block. All other scheduled nodes get put in the schedule here.
2466 int op = n->Opcode();
2467 if( (op == Op_Node && n->req() == 0) || // anti-dependence node OR
2468 (op != Op_Node && // Not an unused antidepedence node and
2469 // not an unallocated boxlock
2470 (OptoReg::is_valid(_regalloc->get_reg_first(n)) || op != Op_BoxLock)) ) {
2471
2472 // Push any trailing projections
2473 if( bb->get_node(bb->number_of_nodes()-1) != n ) {
2474 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2475 Node *foi = n->fast_out(i);
2476 if( foi->is_Proj() )
2477 _scheduled.push(foi);
2478 }
2479 }
2480
2481 // Put the instruction in the schedule list
2482 _scheduled.push(n);
2483 }
2484
2485 #ifndef PRODUCT
2486 if (_cfg->C->trace_opto_output())
2487 dump_available();
2488 #endif
2489
2490 // Walk all the definitions, decrementing use counts, and
2491 // if a definition has a 0 use count, place it in the available list.
2492 DecrementUseCounts(n,bb);
2493 }
2494
2495 // This method sets the use count within a basic block. We will ignore all
2496 // uses outside the current basic block. As we are doing a backwards walk,
2497 // any node we reach that has a use count of 0 may be scheduled. This also
2498 // avoids the problem of cyclic references from phi nodes, as long as phi
2499 // nodes are at the front of the basic block. This method also initializes
2500 // the available list to the set of instructions that have no uses within this
2501 // basic block.
2502 void Scheduling::ComputeUseCount(const Block *bb) {
2503 #ifndef PRODUCT
2504 if (_cfg->C->trace_opto_output())
2505 tty->print("# -> ComputeUseCount\n");
2506 #endif
2507
2508 // Clear the list of available and scheduled instructions, just in case
2509 _available.clear();
2510 _scheduled.clear();
2511
2512 // No delay slot specified
2513 _unconditional_delay_slot = NULL;
2514
2515 #ifdef ASSERT
2516 for( uint i=0; i < bb->number_of_nodes(); i++ )
2517 assert( _uses[bb->get_node(i)->_idx] == 0, "_use array not clean" );
2518 #endif
2519
2520 // Force the _uses count to never go to zero for unscheduable pieces
2521 // of the block
2522 for( uint k = 0; k < _bb_start; k++ )
2523 _uses[bb->get_node(k)->_idx] = 1;
2524 for( uint l = _bb_end; l < bb->number_of_nodes(); l++ )
2525 _uses[bb->get_node(l)->_idx] = 1;
2526
2527 // Iterate backwards over the instructions in the block. Don't count the
2528 // branch projections at end or the block header instructions.
2529 for( uint j = _bb_end-1; j >= _bb_start; j-- ) {
2530 Node *n = bb->get_node(j);
2531 if( n->is_Proj() ) continue; // Projections handled another way
2532
2533 // Account for all uses
2534 for ( uint k = 0; k < n->len(); k++ ) {
2535 Node *inp = n->in(k);
2536 if (!inp) continue;
2537 assert(inp != n, "no cycles allowed" );
2538 if (_cfg->get_block_for_node(inp) == bb) { // Block-local use?
2539 if (inp->is_Proj()) { // Skip through Proj's
2540 inp = inp->in(0);
2541 }
2542 ++_uses[inp->_idx]; // Count 1 block-local use
2543 }
2544 }
2545
2546 // If this instruction has a 0 use count, then it is available
2547 if (!_uses[n->_idx]) {
2548 _current_latency[n->_idx] = _bundle_cycle_number;
2549 AddNodeToAvailableList(n);
2550 }
2551
2552 #ifndef PRODUCT
2553 if (_cfg->C->trace_opto_output()) {
2554 tty->print("# uses: %3d: ", _uses[n->_idx]);
2555 n->dump();
2556 }
2557 #endif
2558 }
2559
2560 #ifndef PRODUCT
2561 if (_cfg->C->trace_opto_output())
2562 tty->print("# <- ComputeUseCount\n");
2563 #endif
2564 }
2565
2566 // This routine performs scheduling on each basic block in reverse order,
2567 // using instruction latencies and taking into account function unit
2568 // availability.
2569 void Scheduling::DoScheduling() {
2570 #ifndef PRODUCT
2571 if (_cfg->C->trace_opto_output())
2572 tty->print("# -> DoScheduling\n");
2573 #endif
2574
2575 Block *succ_bb = NULL;
2576 Block *bb;
2577 Compile* C = Compile::current();
2578
2579 // Walk over all the basic blocks in reverse order
2580 for (int i = _cfg->number_of_blocks() - 1; i >= 0; succ_bb = bb, i--) {
2581 bb = _cfg->get_block(i);
2582
2583 #ifndef PRODUCT
2584 if (_cfg->C->trace_opto_output()) {
2585 tty->print("# Schedule BB#%03d (initial)\n", i);
2586 for (uint j = 0; j < bb->number_of_nodes(); j++) {
2587 bb->get_node(j)->dump();
2588 }
2589 }
2590 #endif
2591
2592 // On the head node, skip processing
2593 if (bb == _cfg->get_root_block()) {
2594 continue;
2595 }
2596
2597 // Skip empty, connector blocks
2598 if (bb->is_connector())
2599 continue;
2600
2601 // If the following block is not the sole successor of
2602 // this one, then reset the pipeline information
2603 if (bb->_num_succs != 1 || bb->non_connector_successor(0) != succ_bb) {
2604 #ifndef PRODUCT
2605 if (_cfg->C->trace_opto_output()) {
2606 tty->print("*** bundle start of next BB, node %d, for %d instructions\n",
2607 _next_node->_idx, _bundle_instr_count);
2608 }
2609 #endif
2610 step_and_clear();
2611 }
2612
2613 // Leave untouched the starting instruction, any Phis, a CreateEx node
2614 // or Top. bb->get_node(_bb_start) is the first schedulable instruction.
2615 _bb_end = bb->number_of_nodes()-1;
2616 for( _bb_start=1; _bb_start <= _bb_end; _bb_start++ ) {
2617 Node *n = bb->get_node(_bb_start);
2618 // Things not matched, like Phinodes and ProjNodes don't get scheduled.
2619 // Also, MachIdealNodes do not get scheduled
2620 if( !n->is_Mach() ) continue; // Skip non-machine nodes
2621 MachNode *mach = n->as_Mach();
2622 int iop = mach->ideal_Opcode();
2623 if( iop == Op_CreateEx ) continue; // CreateEx is pinned
2624 if( iop == Op_Con ) continue; // Do not schedule Top
2625 if( iop == Op_Node && // Do not schedule PhiNodes, ProjNodes
2626 mach->pipeline() == MachNode::pipeline_class() &&
2627 !n->is_SpillCopy() && !n->is_MachMerge() ) // Breakpoints, Prolog, etc
2628 continue;
2629 break; // Funny loop structure to be sure...
2630 }
2631 // Compute last "interesting" instruction in block - last instruction we
2632 // might schedule. _bb_end points just after last schedulable inst. We
2633 // normally schedule conditional branches (despite them being forced last
2634 // in the block), because they have delay slots we can fill. Calls all
2635 // have their delay slots filled in the template expansions, so we don't
2636 // bother scheduling them.
2637 Node *last = bb->get_node(_bb_end);
2638 // Ignore trailing NOPs.
2639 while (_bb_end > 0 && last->is_Mach() &&
2640 last->as_Mach()->ideal_Opcode() == Op_Con) {
2641 last = bb->get_node(--_bb_end);
2642 }
2643 assert(!last->is_Mach() || last->as_Mach()->ideal_Opcode() != Op_Con, "");
2644 if( last->is_Catch() ||
2645 (last->is_Mach() && last->as_Mach()->ideal_Opcode() == Op_Halt) ) {
2646 // There might be a prior call. Skip it.
2647 while (_bb_start < _bb_end && bb->get_node(--_bb_end)->is_MachProj());
2648 } else if( last->is_MachNullCheck() ) {
2649 // Backup so the last null-checked memory instruction is
2650 // outside the schedulable range. Skip over the nullcheck,
2651 // projection, and the memory nodes.
2652 Node *mem = last->in(1);
2653 do {
2654 _bb_end--;
2655 } while (mem != bb->get_node(_bb_end));
2656 } else {
2657 // Set _bb_end to point after last schedulable inst.
2658 _bb_end++;
2659 }
2660
2661 assert( _bb_start <= _bb_end, "inverted block ends" );
2662
2663 // Compute the register antidependencies for the basic block
2664 ComputeRegisterAntidependencies(bb);
2665 if (C->failing()) return; // too many D-U pinch points
2666
2667 // Compute intra-bb latencies for the nodes
2668 ComputeLocalLatenciesForward(bb);
2669
2670 // Compute the usage within the block, and set the list of all nodes
2671 // in the block that have no uses within the block.
2672 ComputeUseCount(bb);
2673
2674 // Schedule the remaining instructions in the block
2675 while ( _available.size() > 0 ) {
2676 Node *n = ChooseNodeToBundle();
2677 guarantee(n != NULL, "no nodes available");
2678 AddNodeToBundle(n,bb);
2679 }
2680
2681 assert( _scheduled.size() == _bb_end - _bb_start, "wrong number of instructions" );
2682 #ifdef ASSERT
2683 for( uint l = _bb_start; l < _bb_end; l++ ) {
2684 Node *n = bb->get_node(l);
2685 uint m;
2686 for( m = 0; m < _bb_end-_bb_start; m++ )
2687 if( _scheduled[m] == n )
2688 break;
2689 assert( m < _bb_end-_bb_start, "instruction missing in schedule" );
2690 }
2691 #endif
2692
2693 // Now copy the instructions (in reverse order) back to the block
2694 for ( uint k = _bb_start; k < _bb_end; k++ )
2695 bb->map_node(_scheduled[_bb_end-k-1], k);
2696
2697 #ifndef PRODUCT
2698 if (_cfg->C->trace_opto_output()) {
2699 tty->print("# Schedule BB#%03d (final)\n", i);
2700 uint current = 0;
2701 for (uint j = 0; j < bb->number_of_nodes(); j++) {
2702 Node *n = bb->get_node(j);
2703 if( valid_bundle_info(n) ) {
2704 Bundle *bundle = node_bundling(n);
2705 if (bundle->instr_count() > 0 || bundle->flags() > 0) {
2706 tty->print("*** Bundle: ");
2707 bundle->dump();
2708 }
2709 n->dump();
2710 }
2711 }
2712 }
2713 #endif
2714 #ifdef ASSERT
2715 verify_good_schedule(bb,"after block local scheduling");
2716 #endif
2717 }
2718
2719 #ifndef PRODUCT
2720 if (_cfg->C->trace_opto_output())
2721 tty->print("# <- DoScheduling\n");
2722 #endif
2723
2724 // Record final node-bundling array location
2725 _regalloc->C->output()->set_node_bundling_base(_node_bundling_base);
2726
2727 } // end DoScheduling
2728
2729 // Verify that no live-range used in the block is killed in the block by a
2730 // wrong DEF. This doesn't verify live-ranges that span blocks.
2731
2732 // Check for edge existence. Used to avoid adding redundant precedence edges.
2733 static bool edge_from_to( Node *from, Node *to ) {
2734 for( uint i=0; i<from->len(); i++ )
2735 if( from->in(i) == to )
2736 return true;
2737 return false;
2738 }
2739
2740 #ifdef ASSERT
2741 void Scheduling::verify_do_def( Node *n, OptoReg::Name def, const char *msg ) {
2742 // Check for bad kills
2743 if( OptoReg::is_valid(def) ) { // Ignore stores & control flow
2744 Node *prior_use = _reg_node[def];
2745 if( prior_use && !edge_from_to(prior_use,n) ) {
2746 tty->print("%s = ",OptoReg::as_VMReg(def)->name());
2747 n->dump();
2748 tty->print_cr("...");
2749 prior_use->dump();
2750 assert(edge_from_to(prior_use,n), "%s", msg);
2751 }
2752 _reg_node.map(def,NULL); // Kill live USEs
2753 }
2754 }
2755
2756 void Scheduling::verify_good_schedule( Block *b, const char *msg ) {
2757
2758 // Zap to something reasonable for the verify code
2759 _reg_node.clear();
2760
2761 // Walk over the block backwards. Check to make sure each DEF doesn't
2762 // kill a live value (other than the one it's supposed to). Add each
2763 // USE to the live set.
2764 for( uint i = b->number_of_nodes()-1; i >= _bb_start; i-- ) {
2765 Node *n = b->get_node(i);
2766 int n_op = n->Opcode();
2767 if( n_op == Op_MachProj && n->ideal_reg() == MachProjNode::fat_proj ) {
2768 // Fat-proj kills a slew of registers
2769 RegMask rm = n->out_RegMask();// Make local copy
2770 while( rm.is_NotEmpty() ) {
2771 OptoReg::Name kill = rm.find_first_elem();
2772 rm.Remove(kill);
2773 verify_do_def( n, kill, msg );
2774 }
2775 } else if( n_op != Op_Node ) { // Avoid brand new antidependence nodes
2776 // Get DEF'd registers the normal way
2777 verify_do_def( n, _regalloc->get_reg_first(n), msg );
2778 verify_do_def( n, _regalloc->get_reg_second(n), msg );
2779 }
2780
2781 // Now make all USEs live
2782 for( uint i=1; i<n->req(); i++ ) {
2783 Node *def = n->in(i);
2784 assert(def != 0, "input edge required");
2785 OptoReg::Name reg_lo = _regalloc->get_reg_first(def);
2786 OptoReg::Name reg_hi = _regalloc->get_reg_second(def);
2787 if( OptoReg::is_valid(reg_lo) ) {
2788 assert(!_reg_node[reg_lo] || edge_from_to(_reg_node[reg_lo],def), "%s", msg);
2789 _reg_node.map(reg_lo,n);
2790 }
2791 if( OptoReg::is_valid(reg_hi) ) {
2792 assert(!_reg_node[reg_hi] || edge_from_to(_reg_node[reg_hi],def), "%s", msg);
2793 _reg_node.map(reg_hi,n);
2794 }
2795 }
2796
2797 }
2798
2799 // Zap to something reasonable for the Antidependence code
2800 _reg_node.clear();
2801 }
2802 #endif
2803
2804 // Conditionally add precedence edges. Avoid putting edges on Projs.
2805 static void add_prec_edge_from_to( Node *from, Node *to ) {
2806 if( from->is_Proj() ) { // Put precedence edge on Proj's input
2807 assert( from->req() == 1 && (from->len() == 1 || from->in(1)==0), "no precedence edges on projections" );
2808 from = from->in(0);
2809 }
2810 if( from != to && // No cycles (for things like LD L0,[L0+4] )
2811 !edge_from_to( from, to ) ) // Avoid duplicate edge
2812 from->add_prec(to);
2813 }
2814
2815 void Scheduling::anti_do_def( Block *b, Node *def, OptoReg::Name def_reg, int is_def ) {
2816 if( !OptoReg::is_valid(def_reg) ) // Ignore stores & control flow
2817 return;
2818
2819 Node *pinch = _reg_node[def_reg]; // Get pinch point
2820 if ((pinch == NULL) || _cfg->get_block_for_node(pinch) != b || // No pinch-point yet?
2821 is_def ) { // Check for a true def (not a kill)
2822 _reg_node.map(def_reg,def); // Record def/kill as the optimistic pinch-point
2823 return;
2824 }
2825
2826 Node *kill = def; // Rename 'def' to more descriptive 'kill'
2827 debug_only( def = (Node*)((intptr_t)0xdeadbeef); )
2828
2829 // After some number of kills there _may_ be a later def
2830 Node *later_def = NULL;
2831
2832 Compile* C = Compile::current();
2833
2834 // Finding a kill requires a real pinch-point.
2835 // Check for not already having a pinch-point.
2836 // Pinch points are Op_Node's.
2837 if( pinch->Opcode() != Op_Node ) { // Or later-def/kill as pinch-point?
2838 later_def = pinch; // Must be def/kill as optimistic pinch-point
2839 if ( _pinch_free_list.size() > 0) {
2840 pinch = _pinch_free_list.pop();
2841 } else {
2842 pinch = new Node(1); // Pinch point to-be
2843 }
2844 if (pinch->_idx >= _regalloc->node_regs_max_index()) {
2845 _cfg->C->record_method_not_compilable("too many D-U pinch points");
2846 return;
2847 }
2848 _cfg->map_node_to_block(pinch, b); // Pretend it's valid in this block (lazy init)
2849 _reg_node.map(def_reg,pinch); // Record pinch-point
2850 //regalloc()->set_bad(pinch->_idx); // Already initialized this way.
2851 if( later_def->outcnt() == 0 || later_def->ideal_reg() == MachProjNode::fat_proj ) { // Distinguish def from kill
2852 pinch->init_req(0, C->top()); // set not NULL for the next call
2853 add_prec_edge_from_to(later_def,pinch); // Add edge from kill to pinch
2854 later_def = NULL; // and no later def
2855 }
2856 pinch->set_req(0,later_def); // Hook later def so we can find it
2857 } else { // Else have valid pinch point
2858 if( pinch->in(0) ) // If there is a later-def
2859 later_def = pinch->in(0); // Get it
2860 }
2861
2862 // Add output-dependence edge from later def to kill
2863 if( later_def ) // If there is some original def
2864 add_prec_edge_from_to(later_def,kill); // Add edge from def to kill
2865
2866 // See if current kill is also a use, and so is forced to be the pinch-point.
2867 if( pinch->Opcode() == Op_Node ) {
2868 Node *uses = kill->is_Proj() ? kill->in(0) : kill;
2869 for( uint i=1; i<uses->req(); i++ ) {
2870 if( _regalloc->get_reg_first(uses->in(i)) == def_reg ||
2871 _regalloc->get_reg_second(uses->in(i)) == def_reg ) {
2872 // Yes, found a use/kill pinch-point
2873 pinch->set_req(0,NULL); //
2874 pinch->replace_by(kill); // Move anti-dep edges up
2875 pinch = kill;
2876 _reg_node.map(def_reg,pinch);
2877 return;
2878 }
2879 }
2880 }
2881
2882 // Add edge from kill to pinch-point
2883 add_prec_edge_from_to(kill,pinch);
2884 }
2885
2886 void Scheduling::anti_do_use( Block *b, Node *use, OptoReg::Name use_reg ) {
2887 if( !OptoReg::is_valid(use_reg) ) // Ignore stores & control flow
2888 return;
2889 Node *pinch = _reg_node[use_reg]; // Get pinch point
2890 // Check for no later def_reg/kill in block
2891 if ((pinch != NULL) && _cfg->get_block_for_node(pinch) == b &&
2892 // Use has to be block-local as well
2893 _cfg->get_block_for_node(use) == b) {
2894 if( pinch->Opcode() == Op_Node && // Real pinch-point (not optimistic?)
2895 pinch->req() == 1 ) { // pinch not yet in block?
2896 pinch->del_req(0); // yank pointer to later-def, also set flag
2897 // Insert the pinch-point in the block just after the last use
2898 b->insert_node(pinch, b->find_node(use) + 1);
2899 _bb_end++; // Increase size scheduled region in block
2900 }
2901
2902 add_prec_edge_from_to(pinch,use);
2903 }
2904 }
2905
2906 // We insert antidependences between the reads and following write of
2907 // allocated registers to prevent illegal code motion. Hopefully, the
2908 // number of added references should be fairly small, especially as we
2909 // are only adding references within the current basic block.
2910 void Scheduling::ComputeRegisterAntidependencies(Block *b) {
2911
2912 #ifdef ASSERT
2913 verify_good_schedule(b,"before block local scheduling");
2914 #endif
2915
2916 // A valid schedule, for each register independently, is an endless cycle
2917 // of: a def, then some uses (connected to the def by true dependencies),
2918 // then some kills (defs with no uses), finally the cycle repeats with a new
2919 // def. The uses are allowed to float relative to each other, as are the
2920 // kills. No use is allowed to slide past a kill (or def). This requires
2921 // antidependencies between all uses of a single def and all kills that
2922 // follow, up to the next def. More edges are redundant, because later defs
2923 // & kills are already serialized with true or antidependencies. To keep
2924 // the edge count down, we add a 'pinch point' node if there's more than
2925 // one use or more than one kill/def.
2926
2927 // We add dependencies in one bottom-up pass.
2928
2929 // For each instruction we handle it's DEFs/KILLs, then it's USEs.
2930
2931 // For each DEF/KILL, we check to see if there's a prior DEF/KILL for this
2932 // register. If not, we record the DEF/KILL in _reg_node, the
2933 // register-to-def mapping. If there is a prior DEF/KILL, we insert a
2934 // "pinch point", a new Node that's in the graph but not in the block.
2935 // We put edges from the prior and current DEF/KILLs to the pinch point.
2936 // We put the pinch point in _reg_node. If there's already a pinch point
2937 // we merely add an edge from the current DEF/KILL to the pinch point.
2938
2939 // After doing the DEF/KILLs, we handle USEs. For each used register, we
2940 // put an edge from the pinch point to the USE.
2941
2942 // To be expedient, the _reg_node array is pre-allocated for the whole
2943 // compilation. _reg_node is lazily initialized; it either contains a NULL,
2944 // or a valid def/kill/pinch-point, or a leftover node from some prior
2945 // block. Leftover node from some prior block is treated like a NULL (no
2946 // prior def, so no anti-dependence needed). Valid def is distinguished by
2947 // it being in the current block.
2948 bool fat_proj_seen = false;
2949 uint last_safept = _bb_end-1;
2950 Node* end_node = (_bb_end-1 >= _bb_start) ? b->get_node(last_safept) : NULL;
2951 Node* last_safept_node = end_node;
2952 for( uint i = _bb_end-1; i >= _bb_start; i-- ) {
2953 Node *n = b->get_node(i);
2954 int is_def = n->outcnt(); // def if some uses prior to adding precedence edges
2955 if( n->is_MachProj() && n->ideal_reg() == MachProjNode::fat_proj ) {
2956 // Fat-proj kills a slew of registers
2957 // This can add edges to 'n' and obscure whether or not it was a def,
2958 // hence the is_def flag.
2959 fat_proj_seen = true;
2960 RegMask rm = n->out_RegMask();// Make local copy
2961 while( rm.is_NotEmpty() ) {
2962 OptoReg::Name kill = rm.find_first_elem();
2963 rm.Remove(kill);
2964 anti_do_def( b, n, kill, is_def );
2965 }
2966 } else {
2967 // Get DEF'd registers the normal way
2968 anti_do_def( b, n, _regalloc->get_reg_first(n), is_def );
2969 anti_do_def( b, n, _regalloc->get_reg_second(n), is_def );
2970 }
2971
2972 // Kill projections on a branch should appear to occur on the
2973 // branch, not afterwards, so grab the masks from the projections
2974 // and process them.
2975 if (n->is_MachBranch() || (n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_Jump)) {
2976 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2977 Node* use = n->fast_out(i);
2978 if (use->is_Proj()) {
2979 RegMask rm = use->out_RegMask();// Make local copy
2980 while( rm.is_NotEmpty() ) {
2981 OptoReg::Name kill = rm.find_first_elem();
2982 rm.Remove(kill);
2983 anti_do_def( b, n, kill, false );
2984 }
2985 }
2986 }
2987 }
2988
2989 // Check each register used by this instruction for a following DEF/KILL
2990 // that must occur afterward and requires an anti-dependence edge.
2991 for( uint j=0; j<n->req(); j++ ) {
2992 Node *def = n->in(j);
2993 if( def ) {
2994 assert( !def->is_MachProj() || def->ideal_reg() != MachProjNode::fat_proj, "" );
2995 anti_do_use( b, n, _regalloc->get_reg_first(def) );
2996 anti_do_use( b, n, _regalloc->get_reg_second(def) );
2997 }
2998 }
2999 // Do not allow defs of new derived values to float above GC
3000 // points unless the base is definitely available at the GC point.
3001
3002 Node *m = b->get_node(i);
3003
3004 // Add precedence edge from following safepoint to use of derived pointer
3005 if( last_safept_node != end_node &&
3006 m != last_safept_node) {
3007 for (uint k = 1; k < m->req(); k++) {
3008 const Type *t = m->in(k)->bottom_type();
3009 if( t->isa_oop_ptr() &&
3010 t->is_ptr()->offset() != 0 ) {
3011 last_safept_node->add_prec( m );
3012 break;
3013 }
3014 }
3015 }
3016
3017 if( n->jvms() ) { // Precedence edge from derived to safept
3018 // Check if last_safept_node was moved by pinch-point insertion in anti_do_use()
3019 if( b->get_node(last_safept) != last_safept_node ) {
3020 last_safept = b->find_node(last_safept_node);
3021 }
3022 for( uint j=last_safept; j > i; j-- ) {
3023 Node *mach = b->get_node(j);
3024 if( mach->is_Mach() && mach->as_Mach()->ideal_Opcode() == Op_AddP )
3025 mach->add_prec( n );
3026 }
3027 last_safept = i;
3028 last_safept_node = m;
3029 }
3030 }
3031
3032 if (fat_proj_seen) {
3033 // Garbage collect pinch nodes that were not consumed.
3034 // They are usually created by a fat kill MachProj for a call.
3035 garbage_collect_pinch_nodes();
3036 }
3037 }
3038
3039 // Garbage collect pinch nodes for reuse by other blocks.
3040 //
3041 // The block scheduler's insertion of anti-dependence
3042 // edges creates many pinch nodes when the block contains
3043 // 2 or more Calls. A pinch node is used to prevent a
3044 // combinatorial explosion of edges. If a set of kills for a
3045 // register is anti-dependent on a set of uses (or defs), rather
3046 // than adding an edge in the graph between each pair of kill
3047 // and use (or def), a pinch is inserted between them:
3048 //
3049 // use1 use2 use3
3050 // \ | /
3051 // \ | /
3052 // pinch
3053 // / | \
3054 // / | \
3055 // kill1 kill2 kill3
3056 //
3057 // One pinch node is created per register killed when
3058 // the second call is encountered during a backwards pass
3059 // over the block. Most of these pinch nodes are never
3060 // wired into the graph because the register is never
3061 // used or def'ed in the block.
3062 //
3063 void Scheduling::garbage_collect_pinch_nodes() {
3064 #ifndef PRODUCT
3065 if (_cfg->C->trace_opto_output()) tty->print("Reclaimed pinch nodes:");
3066 #endif
3067 int trace_cnt = 0;
3068 for (uint k = 0; k < _reg_node.Size(); k++) {
3069 Node* pinch = _reg_node[k];
3070 if ((pinch != NULL) && pinch->Opcode() == Op_Node &&
3071 // no predecence input edges
3072 (pinch->req() == pinch->len() || pinch->in(pinch->req()) == NULL) ) {
3073 cleanup_pinch(pinch);
3074 _pinch_free_list.push(pinch);
3075 _reg_node.map(k, NULL);
3076 #ifndef PRODUCT
3077 if (_cfg->C->trace_opto_output()) {
3078 trace_cnt++;
3079 if (trace_cnt > 40) {
3080 tty->print("\n");
3081 trace_cnt = 0;
3082 }
3083 tty->print(" %d", pinch->_idx);
3084 }
3085 #endif
3086 }
3087 }
3088 #ifndef PRODUCT
3089 if (_cfg->C->trace_opto_output()) tty->print("\n");
3090 #endif
3091 }
3092
3093 // Clean up a pinch node for reuse.
3094 void Scheduling::cleanup_pinch( Node *pinch ) {
3095 assert (pinch && pinch->Opcode() == Op_Node && pinch->req() == 1, "just checking");
3096
3097 for (DUIterator_Last imin, i = pinch->last_outs(imin); i >= imin; ) {
3098 Node* use = pinch->last_out(i);
3099 uint uses_found = 0;
3100 for (uint j = use->req(); j < use->len(); j++) {
3101 if (use->in(j) == pinch) {
3102 use->rm_prec(j);
3103 uses_found++;
3104 }
3105 }
3106 assert(uses_found > 0, "must be a precedence edge");
3107 i -= uses_found; // we deleted 1 or more copies of this edge
3108 }
3109 // May have a later_def entry
3110 pinch->set_req(0, NULL);
3111 }
3112
3113 #ifndef PRODUCT
3114
3115 void Scheduling::dump_available() const {
3116 tty->print("#Availist ");
3117 for (uint i = 0; i < _available.size(); i++)
3118 tty->print(" N%d/l%d", _available[i]->_idx,_current_latency[_available[i]->_idx]);
3119 tty->cr();
3120 }
3121
3122 // Print Scheduling Statistics
3123 void Scheduling::print_statistics() {
3124 // Print the size added by nops for bundling
3125 tty->print("Nops added %d bytes to total of %d bytes",
3126 _total_nop_size, _total_method_size);
3127 if (_total_method_size > 0)
3128 tty->print(", for %.2f%%",
3129 ((double)_total_nop_size) / ((double) _total_method_size) * 100.0);
3130 tty->print("\n");
3131
3132 // Print the number of branch shadows filled
3133 if (Pipeline::_branch_has_delay_slot) {
3134 tty->print("Of %d branches, %d had unconditional delay slots filled",
3135 _total_branches, _total_unconditional_delays);
3136 if (_total_branches > 0)
3137 tty->print(", for %.2f%%",
3138 ((double)_total_unconditional_delays) / ((double)_total_branches) * 100.0);
3139 tty->print("\n");
3140 }
3141
3142 uint total_instructions = 0, total_bundles = 0;
3143
3144 for (uint i = 1; i <= Pipeline::_max_instrs_per_cycle; i++) {
3145 uint bundle_count = _total_instructions_per_bundle[i];
3146 total_instructions += bundle_count * i;
3147 total_bundles += bundle_count;
3148 }
3149
3150 if (total_bundles > 0)
3151 tty->print("Average ILP (excluding nops) is %.2f\n",
3152 ((double)total_instructions) / ((double)total_bundles));
3153 }
3154 #endif
3155
3156 //-----------------------init_scratch_buffer_blob------------------------------
3157 // Construct a temporary BufferBlob and cache it for this compile.
3158 void PhaseOutput::init_scratch_buffer_blob(int const_size) {
3159 // If there is already a scratch buffer blob allocated and the
3160 // constant section is big enough, use it. Otherwise free the
3161 // current and allocate a new one.
3162 BufferBlob* blob = scratch_buffer_blob();
3163 if ((blob != NULL) && (const_size <= _scratch_const_size)) {
3164 // Use the current blob.
3165 } else {
3166 if (blob != NULL) {
3167 BufferBlob::free(blob);
3168 }
3169
3170 ResourceMark rm;
3171 _scratch_const_size = const_size;
3172 int size = C2Compiler::initial_code_buffer_size(const_size);
3173 blob = BufferBlob::create("Compile::scratch_buffer", size);
3174 // Record the buffer blob for next time.
3175 set_scratch_buffer_blob(blob);
3176 // Have we run out of code space?
3177 if (scratch_buffer_blob() == NULL) {
3178 // Let CompilerBroker disable further compilations.
3179 C->record_failure("Not enough space for scratch buffer in CodeCache");
3180 return;
3181 }
3182 }
3183
3184 // Initialize the relocation buffers
3185 relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
3186 set_scratch_locs_memory(locs_buf);
3187 }
3188
3189
3190 //-----------------------scratch_emit_size-------------------------------------
3191 // Helper function that computes size by emitting code
3192 uint PhaseOutput::scratch_emit_size(const Node* n) {
3193 // Start scratch_emit_size section.
3194 set_in_scratch_emit_size(true);
3195
3196 // Emit into a trash buffer and count bytes emitted.
3197 // This is a pretty expensive way to compute a size,
3198 // but it works well enough if seldom used.
3199 // All common fixed-size instructions are given a size
3200 // method by the AD file.
3201 // Note that the scratch buffer blob and locs memory are
3202 // allocated at the beginning of the compile task, and
3203 // may be shared by several calls to scratch_emit_size.
3204 // The allocation of the scratch buffer blob is particularly
3205 // expensive, since it has to grab the code cache lock.
3206 BufferBlob* blob = this->scratch_buffer_blob();
3207 assert(blob != NULL, "Initialize BufferBlob at start");
3208 assert(blob->size() > MAX_inst_size, "sanity");
3209 relocInfo* locs_buf = scratch_locs_memory();
3210 address blob_begin = blob->content_begin();
3211 address blob_end = (address)locs_buf;
3212 assert(blob->contains(blob_end), "sanity");
3213 CodeBuffer buf(blob_begin, blob_end - blob_begin);
3214 buf.initialize_consts_size(_scratch_const_size);
3215 buf.initialize_stubs_size(MAX_stubs_size);
3216 assert(locs_buf != NULL, "sanity");
3217 int lsize = MAX_locs_size / 3;
3218 buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
3219 buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
3220 buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
3221 // Mark as scratch buffer.
3222 buf.consts()->set_scratch_emit();
3223 buf.insts()->set_scratch_emit();
3224 buf.stubs()->set_scratch_emit();
3225
3226 // Do the emission.
3227
3228 Label fakeL; // Fake label for branch instructions.
3229 Label* saveL = NULL;
3230 uint save_bnum = 0;
3231 bool is_branch = n->is_MachBranch();
3232 if (is_branch) {
3233 MacroAssembler masm(&buf);
3234 masm.bind(fakeL);
3235 n->as_MachBranch()->save_label(&saveL, &save_bnum);
3236 n->as_MachBranch()->label_set(&fakeL, 0);
3237 }
3238 n->emit(buf, C->regalloc());
3239
3240 // Emitting into the scratch buffer should not fail
3241 assert (!C->failing(), "Must not have pending failure. Reason is: %s", C->failure_reason());
3242
3243 if (is_branch) // Restore label.
3244 n->as_MachBranch()->label_set(saveL, save_bnum);
3245
3246 // End scratch_emit_size section.
3247 set_in_scratch_emit_size(false);
3248
3249 return buf.insts_size();
3250 }
3251
3252 void PhaseOutput::install() {
3253 if (C->stub_function() != NULL) {
3254 install_stub(C->stub_name(),
3255 C->save_argument_registers());
3256 } else {
3257 install_code(C->method(),
3258 C->entry_bci(),
3259 CompileBroker::compiler2(),
3260 C->has_unsafe_access(),
3261 SharedRuntime::is_wide_vector(C->max_vector_size()),
3262 C->rtm_state());
3263 }
3264 }
3265
3266 void PhaseOutput::install_code(ciMethod* target,
3267 int entry_bci,
3268 AbstractCompiler* compiler,
3269 bool has_unsafe_access,
3270 bool has_wide_vectors,
3271 RTMState rtm_state) {
3272 // Check if we want to skip execution of all compiled code.
3273 {
3274 #ifndef PRODUCT
3275 if (OptoNoExecute) {
3276 C->record_method_not_compilable("+OptoNoExecute"); // Flag as failed
3277 return;
3278 }
3279 #endif
3280 Compile::TracePhase tp("install_code", &timers[_t_registerMethod]);
3281
3282 if (C->is_osr_compilation()) {
3283 _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
3284 _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
3285 } else {
3286 _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
3287 _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
3288 }
3289
3290 C->env()->register_method(target,
3291 entry_bci,
3292 &_code_offsets,
3293 _orig_pc_slot_offset_in_bytes,
3294 code_buffer(),
3295 frame_size_in_words(),
3296 oop_map_set(),
3297 &_handler_table,
3298 inc_table(),
3299 compiler,
3300 has_unsafe_access,
3301 SharedRuntime::is_wide_vector(C->max_vector_size()),
3302 C->rtm_state());
3303
3304 if (C->log() != NULL) { // Print code cache state into compiler log
3305 C->log()->code_cache_state();
3306 }
3307 }
3308 }
3309 void PhaseOutput::install_stub(const char* stub_name,
3310 bool caller_must_gc_arguments) {
3311 // Entry point will be accessed using stub_entry_point();
3312 if (code_buffer() == NULL) {
3313 Matcher::soft_match_failure();
3314 } else {
3315 if (PrintAssembly && (WizardMode || Verbose))
3316 tty->print_cr("### Stub::%s", stub_name);
3317
3318 if (!C->failing()) {
3319 assert(C->fixed_slots() == 0, "no fixed slots used for runtime stubs");
3320
3321 // Make the NMethod
3322 // For now we mark the frame as never safe for profile stackwalking
3323 RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
3324 code_buffer(),
3325 CodeOffsets::frame_never_safe,
3326 // _code_offsets.value(CodeOffsets::Frame_Complete),
3327 frame_size_in_words(),
3328 oop_map_set(),
3329 caller_must_gc_arguments);
3330 assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
3331
3332 C->set_stub_entry_point(rs->entry_point());
3333 }
3334 }
3335 }
3336
3337 // Support for bundling info
3338 Bundle* PhaseOutput::node_bundling(const Node *n) {
3339 assert(valid_bundle_info(n), "oob");
3340 return &_node_bundling_base[n->_idx];
3341 }
3342
3343 bool PhaseOutput::valid_bundle_info(const Node *n) {
3344 return (_node_bundling_limit > n->_idx);
3345 }
3346
3347 //------------------------------frame_size_in_words-----------------------------
3348 // frame_slots in units of words
3349 int PhaseOutput::frame_size_in_words() const {
3350 // shift is 0 in LP32 and 1 in LP64
3351 const int shift = (LogBytesPerWord - LogBytesPerInt);
3352 int words = _frame_slots >> shift;
3353 assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
3354 return words;
3355 }
3356
3357 // To bang the stack of this compiled method we use the stack size
3358 // that the interpreter would need in case of a deoptimization. This
3359 // removes the need to bang the stack in the deoptimization blob which
3360 // in turn simplifies stack overflow handling.
3361 int PhaseOutput::bang_size_in_bytes() const {
3362 return MAX2(frame_size_in_bytes() + os::extra_bang_size_in_bytes(), C->interpreter_frame_size());
3363 }
3364
3365 //------------------------------dump_asm---------------------------------------
3366 // Dump formatted assembly
3367 #if defined(SUPPORT_OPTO_ASSEMBLY)
3368 void PhaseOutput::dump_asm_on(outputStream* st, int* pcs, uint pc_limit) {
3369
3370 int pc_digits = 3; // #chars required for pc
3371 int sb_chars = 3; // #chars for "start bundle" indicator
3372 int tab_size = 8;
3373 if (pcs != NULL) {
3374 int max_pc = 0;
3375 for (uint i = 0; i < pc_limit; i++) {
3376 max_pc = (max_pc < pcs[i]) ? pcs[i] : max_pc;
3377 }
3378 pc_digits = ((max_pc < 4096) ? 3 : ((max_pc < 65536) ? 4 : ((max_pc < 65536*256) ? 6 : 8))); // #chars required for pc
3379 }
3380 int prefix_len = ((pc_digits + sb_chars + tab_size - 1)/tab_size)*tab_size;
3381
3382 bool cut_short = false;
3383 st->print_cr("#");
3384 st->print("# "); C->tf()->dump_on(st); st->cr();
3385 st->print_cr("#");
3386
3387 // For all blocks
3388 int pc = 0x0; // Program counter
3389 char starts_bundle = ' ';
3390 C->regalloc()->dump_frame();
3391
3392 Node *n = NULL;
3393 for (uint i = 0; i < C->cfg()->number_of_blocks(); i++) {
3394 if (VMThread::should_terminate()) {
3395 cut_short = true;
3396 break;
3397 }
3398 Block* block = C->cfg()->get_block(i);
3399 if (block->is_connector() && !Verbose) {
3400 continue;
3401 }
3402 n = block->head();
3403 if ((pcs != NULL) && (n->_idx < pc_limit)) {
3404 pc = pcs[n->_idx];
3405 st->print("%*.*x", pc_digits, pc_digits, pc);
3406 }
3407 st->fill_to(prefix_len);
3408 block->dump_head(C->cfg(), st);
3409 if (block->is_connector()) {
3410 st->fill_to(prefix_len);
3411 st->print_cr("# Empty connector block");
3412 } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
3413 st->fill_to(prefix_len);
3414 st->print_cr("# Block is sole successor of call");
3415 }
3416
3417 // For all instructions
3418 Node *delay = NULL;
3419 for (uint j = 0; j < block->number_of_nodes(); j++) {
3420 if (VMThread::should_terminate()) {
3421 cut_short = true;
3422 break;
3423 }
3424 n = block->get_node(j);
3425 if (valid_bundle_info(n)) {
3426 Bundle* bundle = node_bundling(n);
3427 if (bundle->used_in_unconditional_delay()) {
3428 delay = n;
3429 continue;
3430 }
3431 if (bundle->starts_bundle()) {
3432 starts_bundle = '+';
3433 }
3434 }
3435
3436 if (WizardMode) {
3437 n->dump();
3438 }
3439
3440 if( !n->is_Region() && // Dont print in the Assembly
3441 !n->is_Phi() && // a few noisely useless nodes
3442 !n->is_Proj() &&
3443 !n->is_MachTemp() &&
3444 !n->is_SafePointScalarObject() &&
3445 !n->is_Catch() && // Would be nice to print exception table targets
3446 !n->is_MergeMem() && // Not very interesting
3447 !n->is_top() && // Debug info table constants
3448 !(n->is_Con() && !n->is_Mach())// Debug info table constants
3449 ) {
3450 if ((pcs != NULL) && (n->_idx < pc_limit)) {
3451 pc = pcs[n->_idx];
3452 st->print("%*.*x", pc_digits, pc_digits, pc);
3453 } else {
3454 st->fill_to(pc_digits);
3455 }
3456 st->print(" %c ", starts_bundle);
3457 starts_bundle = ' ';
3458 st->fill_to(prefix_len);
3459 n->format(C->regalloc(), st);
3460 st->cr();
3461 }
3462
3463 // If we have an instruction with a delay slot, and have seen a delay,
3464 // then back up and print it
3465 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
3466 // Coverity finding - Explicit null dereferenced.
3467 guarantee(delay != NULL, "no unconditional delay instruction");
3468 if (WizardMode) delay->dump();
3469
3470 if (node_bundling(delay)->starts_bundle())
3471 starts_bundle = '+';
3472 if ((pcs != NULL) && (n->_idx < pc_limit)) {
3473 pc = pcs[n->_idx];
3474 st->print("%*.*x", pc_digits, pc_digits, pc);
3475 } else {
3476 st->fill_to(pc_digits);
3477 }
3478 st->print(" %c ", starts_bundle);
3479 starts_bundle = ' ';
3480 st->fill_to(prefix_len);
3481 delay->format(C->regalloc(), st);
3482 st->cr();
3483 delay = NULL;
3484 }
3485
3486 // Dump the exception table as well
3487 if( n->is_Catch() && (Verbose || WizardMode) ) {
3488 // Print the exception table for this offset
3489 _handler_table.print_subtable_for(pc);
3490 }
3491 st->bol(); // Make sure we start on a new line
3492 }
3493 st->cr(); // one empty line between blocks
3494 assert(cut_short || delay == NULL, "no unconditional delay branch");
3495 } // End of per-block dump
3496
3497 if (cut_short) st->print_cr("*** disassembly is cut short ***");
3498 }
3499 #endif
3500
3501 #ifndef PRODUCT
3502 void PhaseOutput::print_statistics() {
3503 Scheduling::print_statistics();
3504 }
3505 #endif