1 /*
2 * Copyright (c) 2005, 2024, 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.
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23 */
24
25 #include "precompiled.hpp"
26 #include "opto/addnode.hpp"
27 #include "opto/callnode.hpp"
28 #include "opto/cfgnode.hpp"
29 #include "opto/idealKit.hpp"
30 #include "opto/runtime.hpp"
31
32 // Static initialization
33
34 // This declares the position where vars are kept in the cvstate
35 // For some degree of consistency we use the TypeFunc enum to
36 // soak up spots in the inputs even though we only use early Control
37 // and Memory slots. (So far.)
38 const uint IdealKit::first_var = TypeFunc::Parms + 1;
39
40 //----------------------------IdealKit-----------------------------------------
41 IdealKit::IdealKit(GraphKit* gkit, bool delay_all_transforms, bool has_declarations) :
42 C(gkit->C), _gvn(gkit->gvn()) {
43 _initial_ctrl = gkit->control();
44 _initial_memory = gkit->merged_memory();
45 _initial_i_o = gkit->i_o();
46 _delay_all_transforms = delay_all_transforms;
47 _var_ct = 0;
48 _cvstate = nullptr;
49 // We can go memory state free or else we need the entire memory state
50 assert(_initial_memory == nullptr || _initial_memory->Opcode() == Op_MergeMem, "memory must be pre-split");
51 assert(!_gvn.is_IterGVN(), "IdealKit can't be used during Optimize phase");
52 int init_size = 5;
53 _pending_cvstates = new (C->node_arena()) GrowableArray<Node*>(C->node_arena(), init_size, 0, nullptr);
54 DEBUG_ONLY(_state = new (C->node_arena()) GrowableArray<int>(C->node_arena(), init_size, 0, 0));
55 if (!has_declarations) {
56 declarations_done();
57 }
58 }
59
60 //----------------------------sync_kit-----------------------------------------
61 void IdealKit::sync_kit(GraphKit* gkit) {
62 set_all_memory(gkit->merged_memory());
63 set_i_o(gkit->i_o());
64 set_ctrl(gkit->control());
65 }
66
67 //-------------------------------if_then-------------------------------------
68 // Create: if(left relop right)
69 // / \
70 // iffalse iftrue
71 // Push the iffalse cvstate onto the stack. The iftrue becomes the current cvstate.
72 void IdealKit::if_then(Node* left, BoolTest::mask relop,
73 Node* right, float prob, float cnt, bool push_new_state) {
74 assert((state() & (BlockS|LoopS|IfThenS|ElseS)), "bad state for new If");
75 Node* bol;
76 if (left->bottom_type()->isa_ptr() == nullptr) {
77 if (left->bottom_type()->isa_int() != nullptr) {
78 bol = Bool(CmpI(left, right), relop);
79 } else {
80 assert(left->bottom_type()->isa_long() != nullptr, "what else?");
81 bol = Bool(CmpL(left, right), relop);
82 }
83
84 } else {
85 bol = Bool(CmpP(left, right), relop);
86 }
87 // Delay gvn.transform on if-nodes until construction is finished
88 // to prevent a constant bool input from discarding a control output.
89 IfNode* iff = delay_transform(new IfNode(ctrl(), bol, prob, cnt))->as_If();
90 Node* then = IfTrue(iff);
91 Node* elsen = IfFalse(iff);
92 Node* else_cvstate = copy_cvstate();
93 else_cvstate->set_req(TypeFunc::Control, elsen);
94 _pending_cvstates->push(else_cvstate);
95 DEBUG_ONLY(if (push_new_state) _state->push(IfThenS));
96 set_ctrl(then);
97 }
98
99 //-------------------------------else_-------------------------------------
100 // Pop the else cvstate off the stack, and push the (current) then cvstate.
101 // The else cvstate becomes the current cvstate.
102 void IdealKit::else_() {
103 assert(state() == IfThenS, "bad state for new Else");
104 Node* else_cvstate = _pending_cvstates->pop();
105 DEBUG_ONLY(_state->pop());
106 // save current (then) cvstate for later use at endif
107 _pending_cvstates->push(_cvstate);
108 DEBUG_ONLY(_state->push(ElseS));
109 _cvstate = else_cvstate;
110 }
111
112 //-------------------------------end_if-------------------------------------
113 // Merge the "then" and "else" cvstates.
114 //
115 // The if_then() pushed a copy of the current state for later use
116 // as the initial state for a future "else" clause. The
117 // current state then became the initial state for the
118 // then clause. If an "else" clause was encountered, it will
119 // pop the top state and use it for it's initial state.
120 // It will also push the current state (the state at the end of
121 // the "then" clause) for latter use at the end_if.
122 //
123 // At the endif, the states are:
124 // 1) else exists a) current state is end of "else" clause
125 // b) top stack state is end of "then" clause
126 //
127 // 2) no else: a) current state is end of "then" clause
128 // b) top stack state is from the "if_then" which
129 // would have been the initial state of the else.
130 //
131 // Merging the states is accomplished by:
132 // 1) make a label for the merge
133 // 2) terminate the current state with a goto to the label
134 // 3) pop the top state from the stack and make it the
135 // current state
136 // 4) bind the label at the current state. Binding a label
137 // terminates the current state with a goto to the
138 // label and makes the label's state the current state.
139 //
140 void IdealKit::end_if() {
141 assert(state() & (IfThenS|ElseS), "bad state for new Endif");
142 Node* lab = make_label(1);
143
144 // Node* join_state = _pending_cvstates->pop();
145 /* merging, join */
146 goto_(lab);
147 _cvstate = _pending_cvstates->pop();
148
149 bind(lab);
150 DEBUG_ONLY(_state->pop());
151 }
152
153 //-------------------------------loop-------------------------------------
154 // Create the loop head portion (*) of:
155 // * iv = init
156 // * top: (region node)
157 // * if (iv relop limit) {
158 // loop body
159 // i = i + 1
160 // goto top
161 // * } else // exits loop
162 //
163 // Pushes the loop top cvstate first, then the else (loop exit) cvstate
164 // onto the stack.
165 void IdealKit::loop(GraphKit* gkit, int nargs, IdealVariable& iv, Node* init, BoolTest::mask relop, Node* limit, float prob, float cnt) {
166 assert((state() & (BlockS|LoopS|IfThenS|ElseS)), "bad state for new loop");
167 if (UseLoopPredicate) {
168 // Sync IdealKit and graphKit.
169 gkit->sync_kit(*this);
170 // Add Parse Predicates.
171 gkit->add_parse_predicates(nargs);
172 // Update IdealKit memory.
173 sync_kit(gkit);
174 }
175 set(iv, init);
176 Node* head = make_label(1);
177 bind(head);
178 _pending_cvstates->push(head); // push for use at end_loop
179 _cvstate = copy_cvstate();
180 if_then(value(iv), relop, limit, prob, cnt, false /* no new state */);
181 DEBUG_ONLY(_state->push(LoopS));
182 assert(ctrl()->is_IfTrue(), "true branch stays in loop");
183 assert(_pending_cvstates->top()->in(TypeFunc::Control)->is_IfFalse(), "false branch exits loop");
184 }
185
186 //-------------------------------end_loop-------------------------------------
187 // Creates the goto top label.
188 // Expects the else (loop exit) cvstate to be on top of the
189 // stack, and the loop top cvstate to be 2nd.
190 void IdealKit::end_loop() {
191 assert((state() == LoopS), "bad state for new end_loop");
192 Node* exit = _pending_cvstates->pop();
193 Node* head = _pending_cvstates->pop();
194 goto_(head);
195 clear(head);
196 DEBUG_ONLY(_state->pop());
197 _cvstate = exit;
198 }
199
200 //-------------------------------make_label-------------------------------------
201 // Creates a label. The number of goto's
202 // must be specified (which should be 1 less than
203 // the number of precedessors.)
204 Node* IdealKit::make_label(int goto_ct) {
205 assert(_cvstate != nullptr, "must declare variables before labels");
206 Node* lab = new_cvstate();
207 int sz = 1 + goto_ct + 1 /* fall thru */;
208 Node* reg = delay_transform(new RegionNode(sz));
209 lab->init_req(TypeFunc::Control, reg);
210 return lab;
211 }
212
213 //-------------------------------bind-------------------------------------
214 // Bind a label at the current cvstate by simulating
215 // a goto to the label.
216 void IdealKit::bind(Node* lab) {
217 goto_(lab, true /* bind */);
218 _cvstate = lab;
219 }
220
221 //-------------------------------goto_-------------------------------------
222 // Make the current cvstate a predecessor of the label,
223 // creating phi's to merge values. If bind is true and
224 // this is not the last control edge, then ensure that
225 // all live values have phis created. Used to create phis
226 // at loop-top regions.
227 void IdealKit::goto_(Node* lab, bool bind) {
228 Node* reg = lab->in(TypeFunc::Control);
229 // find next empty slot in region
230 uint slot = 1;
231 while (slot < reg->req() && reg->in(slot) != nullptr) slot++;
232 assert(slot < reg->req(), "too many gotos");
233 // If this is last predecessor, then don't force phi creation
234 if (slot == reg->req() - 1) bind = false;
235 reg->init_req(slot, ctrl());
236 assert(first_var + _var_ct == _cvstate->req(), "bad _cvstate size");
237 for (uint i = first_var; i < _cvstate->req(); i++) {
238
239 // l is the value of var reaching the label. Could be a single value
240 // reaching the label, or a phi that merges multiples values reaching
241 // the label. The latter is true if the label's input: in(..) is
242 // a phi whose control input is the region node for the label.
243
244 Node* l = lab->in(i);
245 // Get the current value of the var
246 Node* m = _cvstate->in(i);
247 // If the var went unused no need for a phi
248 if (m == nullptr) {
249 continue;
250 } else if (l == nullptr || m == l) {
251 // Only one unique value "m" is known to reach this label so a phi
252 // is not yet necessary unless:
253 // the label is being bound and all predecessors have not been seen,
254 // in which case "bind" will be true.
255 if (bind) {
256 m = promote_to_phi(m, reg);
257 }
258 // Record the phi/value used for this var in the label's cvstate
259 lab->set_req(i, m);
260 } else {
261 // More than one value for the variable reaches this label so
262 // a create a phi if one does not already exist.
263 if (!was_promoted_to_phi(l, reg)) {
264 l = promote_to_phi(l, reg);
265 lab->set_req(i, l);
266 }
267 // Record in the phi, the var's value from the current state
268 l->set_req(slot, m);
269 }
270 }
271 do_memory_merge(_cvstate, lab);
272 stop();
273 }
274
275 //-----------------------------promote_to_phi-----------------------------------
276 Node* IdealKit::promote_to_phi(Node* n, Node* reg) {
277 assert(!was_promoted_to_phi(n, reg), "n already promoted to phi on this region");
278 // Get a conservative type for the phi
279 const BasicType bt = n->bottom_type()->basic_type();
280 const Type* ct = Type::get_const_basic_type(bt);
281 return delay_transform(PhiNode::make(reg, n, ct));
282 }
283
284 //-----------------------------declarations_done-------------------------------
285 void IdealKit::declarations_done() {
286 _cvstate = new_cvstate(); // initialize current cvstate
287 set_ctrl(_initial_ctrl); // initialize control in current cvstate
288 set_all_memory(_initial_memory);// initialize memory in current cvstate
289 set_i_o(_initial_i_o); // initialize i_o in current cvstate
290 DEBUG_ONLY(_state->push(BlockS));
291 }
292
293 //-----------------------------transform-----------------------------------
294 Node* IdealKit::transform(Node* n) {
295 if (_delay_all_transforms) {
296 return delay_transform(n);
297 } else {
298 n = gvn().transform(n);
299 C->record_for_igvn(n);
300 return n;
301 }
302 }
303
304 //-----------------------------delay_transform-----------------------------------
305 Node* IdealKit::delay_transform(Node* n) {
306 // Delay transform until IterativeGVN
307 gvn().set_type(n, n->bottom_type());
308 C->record_for_igvn(n);
309 return n;
310 }
311
312 //-----------------------------new_cvstate-----------------------------------
313 Node* IdealKit::new_cvstate() {
314 uint sz = _var_ct + first_var;
315 return new Node(sz);
316 }
317
318 //-----------------------------copy_cvstate-----------------------------------
319 Node* IdealKit::copy_cvstate() {
320 Node* ns = new_cvstate();
321 for (uint i = 0; i < ns->req(); i++) ns->init_req(i, _cvstate->in(i));
322 // We must clone memory since it will be updated as we do stores.
323 ns->set_req(TypeFunc::Memory, MergeMemNode::make(ns->in(TypeFunc::Memory)));
324 return ns;
325 }
326
327 //-----------------------------clear-----------------------------------
328 void IdealKit::clear(Node* m) {
329 for (uint i = 0; i < m->req(); i++) m->set_req(i, nullptr);
330 }
331
332 //-----------------------------IdealVariable----------------------------
333 IdealVariable::IdealVariable(IdealKit &k) {
334 k.declare(this);
335 }
336
337 Node* IdealKit::memory(uint alias_idx) {
338 MergeMemNode* mem = merged_memory();
339 Node* p = mem->memory_at(alias_idx);
340 _gvn.set_type(p, Type::MEMORY); // must be mapped
341 return p;
342 }
343
344 void IdealKit::set_memory(Node* mem, uint alias_idx) {
345 merged_memory()->set_memory_at(alias_idx, mem);
346 }
347
348 //----------------------------- make_load ----------------------------
349 Node* IdealKit::load(Node* ctl,
350 Node* adr,
351 const Type* t,
352 BasicType bt,
353 int adr_idx,
354 bool require_atomic_access,
355 MemNode::MemOrd mo,
356 LoadNode::ControlDependency control_dependency) {
357
358 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
359 const TypePtr* adr_type = nullptr; // debug-mode-only argument
360 debug_only(adr_type = C->get_adr_type(adr_idx));
361 Node* mem = memory(adr_idx);
362 Node* ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, require_atomic_access);
363 return transform(ld);
364 }
365
366 Node* IdealKit::store(Node* ctl, Node* adr, Node *val, BasicType bt,
367 int adr_idx,
368 MemNode::MemOrd mo, bool require_atomic_access,
369 bool mismatched) {
370 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory");
371 const TypePtr* adr_type = nullptr;
372 debug_only(adr_type = C->get_adr_type(adr_idx));
373 Node *mem = memory(adr_idx);
374 Node* st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo, require_atomic_access);
375 if (mismatched) {
376 st->as_Store()->set_mismatched_access();
377 }
378 st = transform(st);
379 set_memory(st, adr_idx);
380
381 return st;
382 }
383
384 //---------------------------- do_memory_merge --------------------------------
385 // The memory from one merging cvstate needs to be merged with the memory for another
386 // join cvstate. If the join cvstate doesn't have a merged memory yet then we
387 // can just copy the state from the merging cvstate
388
389 // Merge one slow path into the rest of memory.
390 void IdealKit::do_memory_merge(Node* merging, Node* join) {
391
392 // Get the region for the join state
393 Node* join_region = join->in(TypeFunc::Control);
394 assert(join_region != nullptr, "join region must exist");
395 if (join->in(TypeFunc::I_O) == nullptr ) {
396 join->set_req(TypeFunc::I_O, merging->in(TypeFunc::I_O));
397 }
398 if (join->in(TypeFunc::Memory) == nullptr ) {
399 join->set_req(TypeFunc::Memory, merging->in(TypeFunc::Memory));
400 return;
401 }
402
403 // The control flow for merging must have already been attached to the join region
404 // we need its index for the phis.
405 uint slot;
406 for (slot = 1; slot < join_region->req() ; slot ++ ) {
407 if (join_region->in(slot) == merging->in(TypeFunc::Control)) break;
408 }
409 assert(slot != join_region->req(), "edge must already exist");
410
411 MergeMemNode* join_m = join->in(TypeFunc::Memory)->as_MergeMem();
412 MergeMemNode* merging_m = merging->in(TypeFunc::Memory)->as_MergeMem();
413
414 // join_m should be an ancestor mergemem of merging
415 // Slow path memory comes from the current map (which is from a slow call)
416 // Fast path/null path memory comes from the call's input
417
418 // Merge the other fast-memory inputs with the new slow-default memory.
419 // for (MergeMemStream mms(merged_memory(), fast_mem->as_MergeMem()); mms.next_non_empty2(); ) {
420 for (MergeMemStream mms(join_m, merging_m); mms.next_non_empty2(); ) {
421 Node* join_slice = mms.force_memory();
422 Node* merging_slice = mms.memory2();
423 if (join_slice != merging_slice) {
424 PhiNode* phi;
425 // bool new_phi = false;
426 // Is the phi for this slice one that we created for this join region or simply
427 // one we copied? If it is ours then add
428 if (join_slice->is_Phi() && join_slice->as_Phi()->region() == join_region) {
429 phi = join_slice->as_Phi();
430 } else {
431 // create the phi with join_slice filling supplying memory for all of the
432 // control edges to the join region
433 phi = PhiNode::make(join_region, join_slice, Type::MEMORY, mms.adr_type(C));
434 phi = (PhiNode*) delay_transform(phi);
435 // gvn().set_type(phi, Type::MEMORY);
436 // new_phi = true;
437 }
438 // Now update the phi with the slice for the merging slice
439 phi->set_req(slot, merging_slice/* slow_path, slow_slice */);
440 // this updates join_m with the phi
441 mms.set_memory(phi);
442 }
443 }
444
445 Node* join_io = join->in(TypeFunc::I_O);
446 Node* merging_io = merging->in(TypeFunc::I_O);
447 if (join_io != merging_io) {
448 PhiNode* phi;
449 if (join_io->is_Phi() && join_io->as_Phi()->region() == join_region) {
450 phi = join_io->as_Phi();
451 } else {
452 phi = PhiNode::make(join_region, join_io, Type::ABIO);
453 phi = (PhiNode*) delay_transform(phi);
454 join->set_req(TypeFunc::I_O, phi);
455 }
456 phi->set_req(slot, merging_io);
457 }
458 }
459
460
461 //----------------------------- make_call ----------------------------
462 // Trivial runtime call
463 Node* IdealKit::make_leaf_call(const TypeFunc *slow_call_type,
464 address slow_call,
465 const char *leaf_name,
466 Node* parm0,
467 Node* parm1,
468 Node* parm2,
469 Node* parm3) {
470
471 // We only handle taking in RawMem and modifying RawMem
472 const TypePtr* adr_type = TypeRawPtr::BOTTOM;
473 uint adr_idx = C->get_alias_index(adr_type);
474
475 // Slow-path leaf call
476 CallNode *call = (CallNode*)new CallLeafNode( slow_call_type, slow_call, leaf_name, adr_type);
477
478 // Set fixed predefined input arguments
479 call->init_req( TypeFunc::Control, ctrl() );
480 call->init_req( TypeFunc::I_O , top() ) ; // does no i/o
481 // Narrow memory as only memory input
482 call->init_req( TypeFunc::Memory , memory(adr_idx));
483 call->init_req( TypeFunc::FramePtr, top() /* frameptr() */ );
484 call->init_req( TypeFunc::ReturnAdr, top() );
485
486 if (parm0 != nullptr) call->init_req(TypeFunc::Parms+0, parm0);
487 if (parm1 != nullptr) call->init_req(TypeFunc::Parms+1, parm1);
488 if (parm2 != nullptr) call->init_req(TypeFunc::Parms+2, parm2);
489 if (parm3 != nullptr) call->init_req(TypeFunc::Parms+3, parm3);
490
491 // Node *c = _gvn.transform(call);
492 call = (CallNode *) _gvn.transform(call);
493 Node *c = call; // dbx gets confused with call call->dump()
494
495 // Slow leaf call has no side-effects, sets few values
496
497 set_ctrl(transform( new ProjNode(call,TypeFunc::Control) ));
498
499 // Make memory for the call
500 Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
501
502 // Set the RawPtr memory state only.
503 set_memory(mem, adr_idx);
504
505 assert(C->alias_type(call->adr_type()) == C->alias_type(adr_type),
506 "call node must be constructed correctly");
507 Node* res = nullptr;
508 if (slow_call_type->range()->cnt() > TypeFunc::Parms) {
509 assert(slow_call_type->range()->cnt() == TypeFunc::Parms+1, "only one return value");
510 res = transform(new ProjNode(call, TypeFunc::Parms));
511 }
512 return res;
513 }
514
515 void IdealKit::make_leaf_call_no_fp(const TypeFunc *slow_call_type,
516 address slow_call,
517 const char *leaf_name,
518 const TypePtr* adr_type,
519 Node* parm0,
520 Node* parm1,
521 Node* parm2,
522 Node* parm3) {
523
524 // We only handle taking in RawMem and modifying RawMem
525 uint adr_idx = C->get_alias_index(adr_type);
526
527 // Slow-path leaf call
528 CallNode *call = (CallNode*)new CallLeafNoFPNode( slow_call_type, slow_call, leaf_name, adr_type);
529
530 // Set fixed predefined input arguments
531 call->init_req( TypeFunc::Control, ctrl() );
532 call->init_req( TypeFunc::I_O , top() ) ; // does no i/o
533 // Narrow memory as only memory input
534 call->init_req( TypeFunc::Memory , memory(adr_idx));
535 call->init_req( TypeFunc::FramePtr, top() /* frameptr() */ );
536 call->init_req( TypeFunc::ReturnAdr, top() );
537
538 if (parm0 != nullptr) call->init_req(TypeFunc::Parms+0, parm0);
539 if (parm1 != nullptr) call->init_req(TypeFunc::Parms+1, parm1);
540 if (parm2 != nullptr) call->init_req(TypeFunc::Parms+2, parm2);
541 if (parm3 != nullptr) call->init_req(TypeFunc::Parms+3, parm3);
542
543 // Node *c = _gvn.transform(call);
544 call = (CallNode *) _gvn.transform(call);
545 Node *c = call; // dbx gets confused with call call->dump()
546
547 // Slow leaf call has no side-effects, sets few values
548
549 set_ctrl(transform( new ProjNode(call,TypeFunc::Control) ));
550
551 // Make memory for the call
552 Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
553
554 // Set the RawPtr memory state only.
555 set_memory(mem, adr_idx);
556
557 assert(C->alias_type(call->adr_type()) == C->alias_type(adr_type),
558 "call node must be constructed correctly");
559 }