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.
22 *
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 int init_size = 5;
52 _pending_cvstates = new (C->node_arena()) GrowableArray<Node*>(C->node_arena(), init_size, 0, nullptr);
53 DEBUG_ONLY(_state = new (C->node_arena()) GrowableArray<int>(C->node_arena(), init_size, 0, 0));
54 if (!has_declarations) {
55 declarations_done();
56 }
57 }
58
59 //----------------------------sync_kit-----------------------------------------
60 void IdealKit::sync_kit(GraphKit* gkit) {
61 set_all_memory(gkit->merged_memory());
62 set_i_o(gkit->i_o());
63 set_ctrl(gkit->control());
64 }
65
66 //-------------------------------if_then-------------------------------------
67 // Create: if(left relop right)
68 // / \
69 // iffalse iftrue
70 // Push the iffalse cvstate onto the stack. The iftrue becomes the current cvstate.
71 void IdealKit::if_then(Node* left, BoolTest::mask relop,
72 Node* right, float prob, float cnt, bool push_new_state) {
73 assert((state() & (BlockS|LoopS|IfThenS|ElseS)), "bad state for new If");
74 Node* bol;
75 if (left->bottom_type()->isa_ptr() == nullptr) {
76 if (left->bottom_type()->isa_int() != nullptr) {
77 bol = Bool(CmpI(left, right), relop);
78 } else {
79 assert(left->bottom_type()->isa_long() != nullptr, "what else?");
80 bol = Bool(CmpL(left, right), relop);
81 }
82 } else {
83 bol = Bool(CmpP(left, right), relop);
84 }
85 if_then(bol, prob, cnt, push_new_state);
86 }
87
88 void IdealKit::if_then(Node* bol, float prob, float cnt, bool push_new_state) {
89 // Delay gvn.transform on if-nodes until construction is finished
90 // to prevent a constant bool input from discarding a control output.
91 IfNode* iff = delay_transform(new IfNode(ctrl(), bol, prob, cnt))->as_If();
92 Node* then = IfTrue(iff);
93 Node* elsen = IfFalse(iff);
94 Node* else_cvstate = copy_cvstate();
95 else_cvstate->set_req(TypeFunc::Control, elsen);
96 _pending_cvstates->push(else_cvstate);
97 DEBUG_ONLY(if (push_new_state) _state->push(IfThenS));
98 set_ctrl(then);
99 }
100
101 //-------------------------------else_-------------------------------------
102 // Pop the else cvstate off the stack, and push the (current) then cvstate.
103 // The else cvstate becomes the current cvstate.
104 void IdealKit::else_() {
105 assert(state() == IfThenS, "bad state for new Else");
106 Node* else_cvstate = _pending_cvstates->pop();
107 DEBUG_ONLY(_state->pop());
108 // save current (then) cvstate for later use at endif
109 _pending_cvstates->push(_cvstate);
110 DEBUG_ONLY(_state->push(ElseS));
111 _cvstate = else_cvstate;
112 }
113
114 //-------------------------------end_if-------------------------------------
115 // Merge the "then" and "else" cvstates.
116 //
117 // The if_then() pushed a copy of the current state for later use
118 // as the initial state for a future "else" clause. The
119 // current state then became the initial state for the
120 // then clause. If an "else" clause was encountered, it will
121 // pop the top state and use it for it's initial state.
122 // It will also push the current state (the state at the end of
123 // the "then" clause) for latter use at the end_if.
124 //
125 // At the endif, the states are:
126 // 1) else exists a) current state is end of "else" clause
127 // b) top stack state is end of "then" clause
128 //
129 // 2) no else: a) current state is end of "then" clause
130 // b) top stack state is from the "if_then" which
131 // would have been the initial state of the else.
132 //
133 // Merging the states is accomplished by:
134 // 1) make a label for the merge
135 // 2) terminate the current state with a goto to the label
136 // 3) pop the top state from the stack and make it the
137 // current state
138 // 4) bind the label at the current state. Binding a label
139 // terminates the current state with a goto to the
140 // label and makes the label's state the current state.
141 //
142 void IdealKit::end_if() {
143 assert(state() & (IfThenS|ElseS), "bad state for new Endif");
144 Node* lab = make_label(1);
145
146 // Node* join_state = _pending_cvstates->pop();
147 /* merging, join */
148 goto_(lab);
149 _cvstate = _pending_cvstates->pop();
150
151 bind(lab);
152 DEBUG_ONLY(_state->pop());
153 }
154
155 //-------------------------------loop-------------------------------------
156 // Create the loop head portion (*) of:
157 // * iv = init
158 // * top: (region node)
159 // * if (iv relop limit) {
160 // loop body
161 // i = i + 1
162 // goto top
163 // * } else // exits loop
164 //
165 // Pushes the loop top cvstate first, then the else (loop exit) cvstate
166 // onto the stack.
167 void IdealKit::loop(GraphKit* gkit, int nargs, IdealVariable& iv, Node* init, BoolTest::mask relop, Node* limit, float prob, float cnt) {
168 assert((state() & (BlockS|LoopS|IfThenS|ElseS)), "bad state for new loop");
169 if (UseLoopPredicate) {
170 // Sync IdealKit and graphKit.
171 gkit->sync_kit(*this);
172 // Add Parse Predicates.
173 gkit->add_parse_predicates(nargs);
174 // Update IdealKit memory.
175 sync_kit(gkit);
176 }
177 set(iv, init);
178 Node* head = make_label(1);
179 bind(head);
180 _pending_cvstates->push(head); // push for use at end_loop
181 _cvstate = copy_cvstate();
182 if_then(value(iv), relop, limit, prob, cnt, false /* no new state */);
183 DEBUG_ONLY(_state->push(LoopS));
184 assert(ctrl()->is_IfTrue(), "true branch stays in loop");
185 assert(_pending_cvstates->top()->in(TypeFunc::Control)->is_IfFalse(), "false branch exits loop");
186 }
187
188 //-------------------------------end_loop-------------------------------------
189 // Creates the goto top label.
190 // Expects the else (loop exit) cvstate to be on top of the
191 // stack, and the loop top cvstate to be 2nd.
192 void IdealKit::end_loop() {
193 assert((state() == LoopS), "bad state for new end_loop");
194 Node* exit = _pending_cvstates->pop();
195 Node* head = _pending_cvstates->pop();
196 goto_(head);
197 clear(head);
198 DEBUG_ONLY(_state->pop());
199 _cvstate = exit;
200 }
201
202 //-------------------------------make_label-------------------------------------
203 // Creates a label. The number of goto's
204 // must be specified (which should be 1 less than
205 // the number of precedessors.)
206 Node* IdealKit::make_label(int goto_ct) {
207 assert(_cvstate != nullptr, "must declare variables before labels");
208 Node* lab = new_cvstate();
209 int sz = 1 + goto_ct + 1 /* fall thru */;
210 Node* reg = delay_transform(new RegionNode(sz));
211 lab->init_req(TypeFunc::Control, reg);
212 return lab;
213 }
214
215 //-------------------------------bind-------------------------------------
216 // Bind a label at the current cvstate by simulating
217 // a goto to the label.
218 void IdealKit::bind(Node* lab) {
219 goto_(lab, true /* bind */);
220 _cvstate = lab;
221 }
222
223 //-------------------------------goto_-------------------------------------
224 // Make the current cvstate a predecessor of the label,
225 // creating phi's to merge values. If bind is true and
226 // this is not the last control edge, then ensure that
227 // all live values have phis created. Used to create phis
228 // at loop-top regions.
229 void IdealKit::goto_(Node* lab, bool bind) {
230 Node* reg = lab->in(TypeFunc::Control);
231 // find next empty slot in region
232 uint slot = 1;
233 while (slot < reg->req() && reg->in(slot) != nullptr) slot++;
234 assert(slot < reg->req(), "too many gotos");
235 // If this is last predecessor, then don't force phi creation
236 if (slot == reg->req() - 1) bind = false;
237 reg->init_req(slot, ctrl());
238 assert(first_var + _var_ct == _cvstate->req(), "bad _cvstate size");
239 for (uint i = first_var; i < _cvstate->req(); i++) {
240
241 // l is the value of var reaching the label. Could be a single value
242 // reaching the label, or a phi that merges multiples values reaching
243 // the label. The latter is true if the label's input: in(..) is
244 // a phi whose control input is the region node for the label.
245
246 Node* l = lab->in(i);
247 // Get the current value of the var
248 Node* m = _cvstate->in(i);
249 // If the var went unused no need for a phi
250 if (m == nullptr) {
251 continue;
252 } else if (l == nullptr || m == l) {
253 // Only one unique value "m" is known to reach this label so a phi
254 // is not yet necessary unless:
255 // the label is being bound and all predecessors have not been seen,
256 // in which case "bind" will be true.
257 if (bind) {
258 m = promote_to_phi(m, reg);
259 }
260 // Record the phi/value used for this var in the label's cvstate
261 lab->set_req(i, m);
262 } else {
263 // More than one value for the variable reaches this label so
264 // a create a phi if one does not already exist.
265 if (!was_promoted_to_phi(l, reg)) {
266 l = promote_to_phi(l, reg);
267 lab->set_req(i, l);
268 }
269 // Record in the phi, the var's value from the current state
270 l->set_req(slot, m);
271 }
272 }
273 do_memory_merge(_cvstate, lab);
274 stop();
275 }
276
277 //-----------------------------promote_to_phi-----------------------------------
278 Node* IdealKit::promote_to_phi(Node* n, Node* reg) {
279 assert(!was_promoted_to_phi(n, reg), "n already promoted to phi on this region");
280 // Get a conservative type for the phi
281 const BasicType bt = n->bottom_type()->basic_type();
282 const Type* ct = Type::get_const_basic_type(bt);
283 return delay_transform(PhiNode::make(reg, n, ct));
284 }
285
286 //-----------------------------declarations_done-------------------------------
287 void IdealKit::declarations_done() {
288 _cvstate = new_cvstate(); // initialize current cvstate
289 set_ctrl(_initial_ctrl); // initialize control in current cvstate
290 set_all_memory(_initial_memory);// initialize memory in current cvstate
291 set_i_o(_initial_i_o); // initialize i_o in current cvstate
292 DEBUG_ONLY(_state->push(BlockS));
293 }
294
295 //-----------------------------transform-----------------------------------
296 Node* IdealKit::transform(Node* n) {
297 if (_delay_all_transforms) {
298 return delay_transform(n);
299 } else {
300 n = gvn().transform(n);
301 gvn().record_for_igvn(n);
302 return n;
303 }
304 }
305
306 //-----------------------------delay_transform-----------------------------------
307 Node* IdealKit::delay_transform(Node* n) {
308 // Delay transform until IterativeGVN
309 gvn().set_type(n, n->bottom_type());
310 gvn().record_for_igvn(n);
311 return n;
312 }
313
314 //-----------------------------new_cvstate-----------------------------------
315 Node* IdealKit::new_cvstate() {
316 uint sz = _var_ct + first_var;
317 return new Node(sz);
318 }
319
320 //-----------------------------copy_cvstate-----------------------------------
321 Node* IdealKit::copy_cvstate() {
322 Node* ns = new_cvstate();
323 for (uint i = 0; i < ns->req(); i++) ns->init_req(i, _cvstate->in(i));
324 // We must clone memory since it will be updated as we do stores.
325 ns->set_req(TypeFunc::Memory, MergeMemNode::make(ns->in(TypeFunc::Memory)));
326 return ns;
327 }
328
329 //-----------------------------clear-----------------------------------
330 void IdealKit::clear(Node* m) {
331 for (uint i = 0; i < m->req(); i++) m->set_req(i, nullptr);
332 }
333
334 //-----------------------------IdealVariable----------------------------
335 IdealVariable::IdealVariable(IdealKit &k) {
336 k.declare(this);
337 }
338
339 Node* IdealKit::memory(uint alias_idx) {
340 MergeMemNode* mem = merged_memory();
341 Node* p = mem->memory_at(alias_idx);
342 _gvn.set_type(p, Type::MEMORY); // must be mapped
343 return p;
344 }
345
346 void IdealKit::set_memory(Node* mem, uint alias_idx) {
347 merged_memory()->set_memory_at(alias_idx, mem);
348 }
349
350 //----------------------------- make_load ----------------------------
351 Node* IdealKit::load(Node* ctl,
352 Node* adr,
353 const Type* t,
354 BasicType bt,
355 int adr_idx,
356 bool require_atomic_access,
357 MemNode::MemOrd mo,
358 LoadNode::ControlDependency control_dependency) {
359
360 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
361 const TypePtr* adr_type = nullptr; // debug-mode-only argument
362 debug_only(adr_type = C->get_adr_type(adr_idx));
363 Node* mem = memory(adr_idx);
364 Node* ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, require_atomic_access);
365 return transform(ld);
366 }
367
368 Node* IdealKit::store(Node* ctl, Node* adr, Node *val, BasicType bt,
369 int adr_idx,
370 MemNode::MemOrd mo, bool require_atomic_access,
371 bool mismatched) {
372 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory");
373 const TypePtr* adr_type = nullptr;
374 debug_only(adr_type = C->get_adr_type(adr_idx));
375 Node *mem = memory(adr_idx);
376 Node* st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo, require_atomic_access);
377 if (mismatched) {
378 st->as_Store()->set_mismatched_access();
379 }
380 st = transform(st);
381 set_memory(st, adr_idx);
382
383 return st;
384 }
385
386 //---------------------------- do_memory_merge --------------------------------
387 // The memory from one merging cvstate needs to be merged with the memory for another
388 // join cvstate. If the join cvstate doesn't have a merged memory yet then we
389 // can just copy the state from the merging cvstate
390
391 // Merge one slow path into the rest of memory.
392 void IdealKit::do_memory_merge(Node* merging, Node* join) {
393
394 // Get the region for the join state
395 Node* join_region = join->in(TypeFunc::Control);
396 assert(join_region != nullptr, "join region must exist");
397 if (join->in(TypeFunc::I_O) == nullptr ) {
398 join->set_req(TypeFunc::I_O, merging->in(TypeFunc::I_O));
399 }
400 if (join->in(TypeFunc::Memory) == nullptr ) {
401 join->set_req(TypeFunc::Memory, merging->in(TypeFunc::Memory));
402 return;
403 }
404
405 // The control flow for merging must have already been attached to the join region
406 // we need its index for the phis.
407 uint slot;
408 for (slot = 1; slot < join_region->req() ; slot ++ ) {
409 if (join_region->in(slot) == merging->in(TypeFunc::Control)) break;
410 }
411 assert(slot != join_region->req(), "edge must already exist");
412
413 MergeMemNode* join_m = join->in(TypeFunc::Memory)->as_MergeMem();
414 MergeMemNode* merging_m = merging->in(TypeFunc::Memory)->as_MergeMem();
415
416 // join_m should be an ancestor mergemem of merging
417 // Slow path memory comes from the current map (which is from a slow call)
418 // Fast path/null path memory comes from the call's input
419
420 // Merge the other fast-memory inputs with the new slow-default memory.
421 // for (MergeMemStream mms(merged_memory(), fast_mem->as_MergeMem()); mms.next_non_empty2(); ) {
422 for (MergeMemStream mms(join_m, merging_m); mms.next_non_empty2(); ) {
423 Node* join_slice = mms.force_memory();
424 Node* merging_slice = mms.memory2();
425 if (join_slice != merging_slice) {
426 PhiNode* phi;
427 // bool new_phi = false;
428 // Is the phi for this slice one that we created for this join region or simply
429 // one we copied? If it is ours then add
430 if (join_slice->is_Phi() && join_slice->as_Phi()->region() == join_region) {
431 phi = join_slice->as_Phi();
432 } else {
433 // create the phi with join_slice filling supplying memory for all of the
434 // control edges to the join region
435 phi = PhiNode::make(join_region, join_slice, Type::MEMORY, mms.adr_type(C));
436 phi = (PhiNode*) delay_transform(phi);
437 // gvn().set_type(phi, Type::MEMORY);
438 // new_phi = true;
439 }
440 // Now update the phi with the slice for the merging slice
441 phi->set_req(slot, merging_slice/* slow_path, slow_slice */);
442 // this updates join_m with the phi
443 mms.set_memory(phi);
444 }
445 }
446
447 Node* join_io = join->in(TypeFunc::I_O);
448 Node* merging_io = merging->in(TypeFunc::I_O);
449 if (join_io != merging_io) {
450 PhiNode* phi;
451 if (join_io->is_Phi() && join_io->as_Phi()->region() == join_region) {
452 phi = join_io->as_Phi();
453 } else {
454 phi = PhiNode::make(join_region, join_io, Type::ABIO);
455 phi = (PhiNode*) delay_transform(phi);
456 join->set_req(TypeFunc::I_O, phi);
457 }
458 phi->set_req(slot, merging_io);
459 }
460 }
461
462
463 //----------------------------- make_call ----------------------------
464 // Trivial runtime call
465 Node* IdealKit::make_leaf_call(const TypeFunc *slow_call_type,
466 address slow_call,
467 const char *leaf_name,
468 Node* parm0,
469 Node* parm1,
470 Node* parm2,
471 Node* parm3) {
472
473 // We only handle taking in RawMem and modifying RawMem
474 const TypePtr* adr_type = TypeRawPtr::BOTTOM;
475 uint adr_idx = C->get_alias_index(adr_type);
476
477 // Slow-path leaf call
478 CallNode *call = (CallNode*)new CallLeafNode( slow_call_type, slow_call, leaf_name, adr_type);
479
480 // Set fixed predefined input arguments
481 call->init_req( TypeFunc::Control, ctrl() );
482 call->init_req( TypeFunc::I_O , top() ) ; // does no i/o
483 // Narrow memory as only memory input
484 call->init_req( TypeFunc::Memory , memory(adr_idx));
485 call->init_req( TypeFunc::FramePtr, top() /* frameptr() */ );
486 call->init_req( TypeFunc::ReturnAdr, top() );
487
488 if (parm0 != nullptr) call->init_req(TypeFunc::Parms+0, parm0);
489 if (parm1 != nullptr) call->init_req(TypeFunc::Parms+1, parm1);
490 if (parm2 != nullptr) call->init_req(TypeFunc::Parms+2, parm2);
491 if (parm3 != nullptr) call->init_req(TypeFunc::Parms+3, parm3);
492
493 // Node *c = _gvn.transform(call);
494 call = (CallNode *) _gvn.transform(call);
495 Node *c = call; // dbx gets confused with call call->dump()
496
497 // Slow leaf call has no side-effects, sets few values
498
499 set_ctrl(transform( new ProjNode(call,TypeFunc::Control) ));
500
501 // Make memory for the call
502 Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
503
504 // Set the RawPtr memory state only.
505 set_memory(mem, adr_idx);
506
507 assert(C->alias_type(call->adr_type()) == C->alias_type(adr_type),
508 "call node must be constructed correctly");
509 Node* res = nullptr;
510 if (slow_call_type->range_sig()->cnt() > TypeFunc::Parms) {
511 assert(slow_call_type->range_sig()->cnt() == TypeFunc::Parms+1, "only one return value");
512 res = transform(new ProjNode(call, TypeFunc::Parms));
513 }
514 return res;
515 }
516
517 void IdealKit::make_leaf_call_no_fp(const TypeFunc *slow_call_type,
518 address slow_call,
519 const char *leaf_name,
520 const TypePtr* adr_type,
521 Node* parm0,
522 Node* parm1,
523 Node* parm2,
524 Node* parm3) {
525
526 // We only handle taking in RawMem and modifying RawMem
527 uint adr_idx = C->get_alias_index(adr_type);
528
529 // Slow-path leaf call
530 CallNode *call = (CallNode*)new CallLeafNoFPNode( slow_call_type, slow_call, leaf_name, adr_type);
531
532 // Set fixed predefined input arguments
533 call->init_req( TypeFunc::Control, ctrl() );
534 call->init_req( TypeFunc::I_O , top() ) ; // does no i/o
535 // Narrow memory as only memory input
536 call->init_req( TypeFunc::Memory , memory(adr_idx));
537 call->init_req( TypeFunc::FramePtr, top() /* frameptr() */ );
538 call->init_req( TypeFunc::ReturnAdr, top() );
539
540 if (parm0 != nullptr) call->init_req(TypeFunc::Parms+0, parm0);
541 if (parm1 != nullptr) call->init_req(TypeFunc::Parms+1, parm1);
542 if (parm2 != nullptr) call->init_req(TypeFunc::Parms+2, parm2);
543 if (parm3 != nullptr) call->init_req(TypeFunc::Parms+3, parm3);
544
545 // Node *c = _gvn.transform(call);
546 call = (CallNode *) _gvn.transform(call);
547 Node *c = call; // dbx gets confused with call call->dump()
548
549 // Slow leaf call has no side-effects, sets few values
550
551 set_ctrl(transform( new ProjNode(call,TypeFunc::Control) ));
552
553 // Make memory for the call
554 Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
555
556 // Set the RawPtr memory state only.
557 set_memory(mem, adr_idx);
558
559 assert(C->alias_type(call->adr_type()) == C->alias_type(adr_type),
560 "call node must be constructed correctly");
561 }