1 /*
2 * Copyright (c) 1997, 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.
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23 */
24
25 #include "precompiled.hpp"
26 #include "memory/allocation.inline.hpp"
27 #include "opto/addnode.hpp"
28 #include "opto/castnode.hpp"
29 #include "opto/cfgnode.hpp"
30 #include "opto/connode.hpp"
31 #include "opto/machnode.hpp"
32 #include "opto/movenode.hpp"
33 #include "opto/mulnode.hpp"
34 #include "opto/phaseX.hpp"
35 #include "opto/subnode.hpp"
36
37 // Portions of code courtesy of Clifford Click
38
39 // Classic Add functionality. This covers all the usual 'add' behaviors for
40 // an algebraic ring. Add-integer, add-float, add-double, and binary-or are
41 // all inherited from this class. The various identity values are supplied
42 // by virtual functions.
43
44
45 //=============================================================================
46 //------------------------------hash-------------------------------------------
47 // Hash function over AddNodes. Needs to be commutative; i.e., I swap
48 // (commute) inputs to AddNodes willy-nilly so the hash function must return
49 // the same value in the presence of edge swapping.
50 uint AddNode::hash() const {
51 return (uintptr_t)in(1) + (uintptr_t)in(2) + Opcode();
52 }
53
54 //------------------------------Identity---------------------------------------
55 // If either input is a constant 0, return the other input.
56 Node* AddNode::Identity(PhaseGVN* phase) {
57 const Type *zero = add_id(); // The additive identity
58 if( phase->type( in(1) )->higher_equal( zero ) ) return in(2);
59 if( phase->type( in(2) )->higher_equal( zero ) ) return in(1);
60 return this;
61 }
62
63 //------------------------------commute----------------------------------------
64 // Commute operands to move loads and constants to the right.
65 static bool commute(PhaseGVN* phase, Node* add) {
66 Node *in1 = add->in(1);
67 Node *in2 = add->in(2);
68
69 // convert "max(a,b) + min(a,b)" into "a+b".
70 if ((in1->Opcode() == add->as_Add()->max_opcode() && in2->Opcode() == add->as_Add()->min_opcode())
71 || (in1->Opcode() == add->as_Add()->min_opcode() && in2->Opcode() == add->as_Add()->max_opcode())) {
72 Node *in11 = in1->in(1);
73 Node *in12 = in1->in(2);
74
75 Node *in21 = in2->in(1);
76 Node *in22 = in2->in(2);
77
78 if ((in11 == in21 && in12 == in22) ||
79 (in11 == in22 && in12 == in21)) {
80 add->set_req_X(1, in11, phase);
81 add->set_req_X(2, in12, phase);
82 return true;
83 }
84 }
85
86 bool con_left = phase->type(in1)->singleton();
87 bool con_right = phase->type(in2)->singleton();
88
89 // Convert "1+x" into "x+1".
90 // Right is a constant; leave it
91 if( con_right ) return false;
92 // Left is a constant; move it right.
93 if( con_left ) {
94 add->swap_edges(1, 2);
95 return true;
96 }
97
98 // Convert "Load+x" into "x+Load".
99 // Now check for loads
100 if (in2->is_Load()) {
101 if (!in1->is_Load()) {
102 // already x+Load to return
103 return false;
104 }
105 // both are loads, so fall through to sort inputs by idx
106 } else if( in1->is_Load() ) {
107 // Left is a Load and Right is not; move it right.
108 add->swap_edges(1, 2);
109 return true;
110 }
111
112 PhiNode *phi;
113 // Check for tight loop increments: Loop-phi of Add of loop-phi
114 if (in1->is_Phi() && (phi = in1->as_Phi()) && phi->region()->is_Loop() && phi->in(2) == add)
115 return false;
116 if (in2->is_Phi() && (phi = in2->as_Phi()) && phi->region()->is_Loop() && phi->in(2) == add) {
117 add->swap_edges(1, 2);
118 return true;
119 }
120
121 // Otherwise, sort inputs (commutativity) to help value numbering.
122 if( in1->_idx > in2->_idx ) {
123 add->swap_edges(1, 2);
124 return true;
125 }
126 return false;
127 }
128
129 //------------------------------Idealize---------------------------------------
130 // If we get here, we assume we are associative!
131 Node *AddNode::Ideal(PhaseGVN *phase, bool can_reshape) {
132 const Type *t1 = phase->type(in(1));
133 const Type *t2 = phase->type(in(2));
134 bool con_left = t1->singleton();
135 bool con_right = t2->singleton();
136
137 // Check for commutative operation desired
138 if (commute(phase, this)) return this;
139
140 AddNode *progress = nullptr; // Progress flag
141
142 // Convert "(x+1)+2" into "x+(1+2)". If the right input is a
143 // constant, and the left input is an add of a constant, flatten the
144 // expression tree.
145 Node *add1 = in(1);
146 Node *add2 = in(2);
147 int add1_op = add1->Opcode();
148 int this_op = Opcode();
149 if (con_right && t2 != Type::TOP && // Right input is a constant?
150 add1_op == this_op) { // Left input is an Add?
151
152 // Type of left _in right input
153 const Type *t12 = phase->type(add1->in(2));
154 if (t12->singleton() && t12 != Type::TOP) { // Left input is an add of a constant?
155 // Check for rare case of closed data cycle which can happen inside
156 // unreachable loops. In these cases the computation is undefined.
157 #ifdef ASSERT
158 Node *add11 = add1->in(1);
159 int add11_op = add11->Opcode();
160 if ((add1 == add1->in(1))
161 || (add11_op == this_op && add11->in(1) == add1)) {
162 assert(false, "dead loop in AddNode::Ideal");
163 }
164 #endif
165 // The Add of the flattened expression
166 Node *x1 = add1->in(1);
167 Node *x2 = phase->makecon(add1->as_Add()->add_ring(t2, t12));
168 set_req_X(2, x2, phase);
169 set_req_X(1, x1, phase);
170 progress = this; // Made progress
171 add1 = in(1);
172 add1_op = add1->Opcode();
173 }
174 }
175
176 // Convert "(x+1)+y" into "(x+y)+1". Push constants down the expression tree.
177 if (add1_op == this_op && !con_right) {
178 Node *a12 = add1->in(2);
179 const Type *t12 = phase->type( a12 );
180 if (t12->singleton() && t12 != Type::TOP && (add1 != add1->in(1)) &&
181 !(add1->in(1)->is_Phi() && (add1->in(1)->as_Phi()->is_tripcount(T_INT) || add1->in(1)->as_Phi()->is_tripcount(T_LONG)))) {
182 assert(add1->in(1) != this, "dead loop in AddNode::Ideal");
183 add2 = add1->clone();
184 add2->set_req(2, in(2));
185 add2 = phase->transform(add2);
186 set_req_X(1, add2, phase);
187 set_req_X(2, a12, phase);
188 progress = this;
189 add2 = a12;
190 }
191 }
192
193 // Convert "x+(y+1)" into "(x+y)+1". Push constants down the expression tree.
194 int add2_op = add2->Opcode();
195 if (add2_op == this_op && !con_left) {
196 Node *a22 = add2->in(2);
197 const Type *t22 = phase->type( a22 );
198 if (t22->singleton() && t22 != Type::TOP && (add2 != add2->in(1)) &&
199 !(add2->in(1)->is_Phi() && (add2->in(1)->as_Phi()->is_tripcount(T_INT) || add2->in(1)->as_Phi()->is_tripcount(T_LONG)))) {
200 assert(add2->in(1) != this, "dead loop in AddNode::Ideal");
201 Node *addx = add2->clone();
202 addx->set_req(1, in(1));
203 addx->set_req(2, add2->in(1));
204 addx = phase->transform(addx);
205 set_req_X(1, addx, phase);
206 set_req_X(2, a22, phase);
207 progress = this;
208 }
209 }
210
211 return progress;
212 }
213
214 //------------------------------Value-----------------------------------------
215 // An add node sums it's two _in. If one input is an RSD, we must mixin
216 // the other input's symbols.
217 const Type* AddNode::Value(PhaseGVN* phase) const {
218 // Either input is TOP ==> the result is TOP
219 const Type* t1 = phase->type(in(1));
220 const Type* t2 = phase->type(in(2));
221 if (t1 == Type::TOP || t2 == Type::TOP) {
222 return Type::TOP;
223 }
224
225 // Check for an addition involving the additive identity
226 const Type* tadd = add_of_identity(t1, t2);
227 if (tadd != nullptr) {
228 return tadd;
229 }
230
231 return add_ring(t1, t2); // Local flavor of type addition
232 }
233
234 //------------------------------add_identity-----------------------------------
235 // Check for addition of the identity
236 const Type *AddNode::add_of_identity( const Type *t1, const Type *t2 ) const {
237 const Type *zero = add_id(); // The additive identity
238 if( t1->higher_equal( zero ) ) return t2;
239 if( t2->higher_equal( zero ) ) return t1;
240
241 return nullptr;
242 }
243
244 AddNode* AddNode::make(Node* in1, Node* in2, BasicType bt) {
245 switch (bt) {
246 case T_INT:
247 return new AddINode(in1, in2);
248 case T_LONG:
249 return new AddLNode(in1, in2);
250 default:
251 fatal("Not implemented for %s", type2name(bt));
252 }
253 return nullptr;
254 }
255
256 bool AddNode::is_not(PhaseGVN* phase, Node* n, BasicType bt) {
257 return n->Opcode() == Op_Xor(bt) && phase->type(n->in(2)) == TypeInteger::minus_1(bt);
258 }
259
260 AddNode* AddNode::make_not(PhaseGVN* phase, Node* n, BasicType bt) {
261 switch (bt) {
262 case T_INT:
263 return new XorINode(n, phase->intcon(-1));
264 case T_LONG:
265 return new XorLNode(n, phase->longcon(-1L));
266 default:
267 fatal("Not implemented for %s", type2name(bt));
268 }
269 return nullptr;
270 }
271
272 //=============================================================================
273 //------------------------------Idealize---------------------------------------
274 Node* AddNode::IdealIL(PhaseGVN* phase, bool can_reshape, BasicType bt) {
275 Node* in1 = in(1);
276 Node* in2 = in(2);
277 int op1 = in1->Opcode();
278 int op2 = in2->Opcode();
279 // Fold (con1-x)+con2 into (con1+con2)-x
280 if (op1 == Op_Add(bt) && op2 == Op_Sub(bt)) {
281 // Swap edges to try optimizations below
282 in1 = in2;
283 in2 = in(1);
284 op1 = op2;
285 op2 = in2->Opcode();
286 }
287 if (op1 == Op_Sub(bt)) {
288 const Type* t_sub1 = phase->type(in1->in(1));
289 const Type* t_2 = phase->type(in2 );
290 if (t_sub1->singleton() && t_2->singleton() && t_sub1 != Type::TOP && t_2 != Type::TOP) {
291 return SubNode::make(phase->makecon(add_ring(t_sub1, t_2)), in1->in(2), bt);
292 }
293 // Convert "(a-b)+(c-d)" into "(a+c)-(b+d)"
294 if (op2 == Op_Sub(bt)) {
295 // Check for dead cycle: d = (a-b)+(c-d)
296 assert( in1->in(2) != this && in2->in(2) != this,
297 "dead loop in AddINode::Ideal" );
298 Node* sub = SubNode::make(nullptr, nullptr, bt);
299 Node* sub_in1;
300 PhaseIterGVN* igvn = phase->is_IterGVN();
301 // During IGVN, if both inputs of the new AddNode are a tree of SubNodes, this same transformation will be applied
302 // to every node of the tree. Calling transform() causes the transformation to be applied recursively, once per
303 // tree node whether some subtrees are identical or not. Pushing to the IGVN worklist instead, causes the transform
304 // to be applied once per unique subtrees (because all uses of a subtree are updated with the result of the
305 // transformation). In case of a large tree, this can make a difference in compilation time.
306 if (igvn != nullptr) {
307 sub_in1 = igvn->register_new_node_with_optimizer(AddNode::make(in1->in(1), in2->in(1), bt));
308 } else {
309 sub_in1 = phase->transform(AddNode::make(in1->in(1), in2->in(1), bt));
310 }
311 Node* sub_in2;
312 if (igvn != nullptr) {
313 sub_in2 = igvn->register_new_node_with_optimizer(AddNode::make(in1->in(2), in2->in(2), bt));
314 } else {
315 sub_in2 = phase->transform(AddNode::make(in1->in(2), in2->in(2), bt));
316 }
317 sub->init_req(1, sub_in1);
318 sub->init_req(2, sub_in2);
319 return sub;
320 }
321 // Convert "(a-b)+(b+c)" into "(a+c)"
322 if (op2 == Op_Add(bt) && in1->in(2) == in2->in(1)) {
323 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddINode::Ideal/AddLNode::Ideal");
324 return AddNode::make(in1->in(1), in2->in(2), bt);
325 }
326 // Convert "(a-b)+(c+b)" into "(a+c)"
327 if (op2 == Op_Add(bt) && in1->in(2) == in2->in(2)) {
328 assert(in1->in(1) != this && in2->in(1) != this,"dead loop in AddINode::Ideal/AddLNode::Ideal");
329 return AddNode::make(in1->in(1), in2->in(1), bt);
330 }
331 }
332
333 // Convert (con - y) + x into "(x - y) + con"
334 if (op1 == Op_Sub(bt) && in1->in(1)->Opcode() == Op_ConIL(bt)
335 && in1 != in1->in(2) && !(in1->in(2)->is_Phi() && in1->in(2)->as_Phi()->is_tripcount(bt))) {
336 return AddNode::make(phase->transform(SubNode::make(in2, in1->in(2), bt)), in1->in(1), bt);
337 }
338
339 // Convert x + (con - y) into "(x - y) + con"
340 if (op2 == Op_Sub(bt) && in2->in(1)->Opcode() == Op_ConIL(bt)
341 && in2 != in2->in(2) && !(in2->in(2)->is_Phi() && in2->in(2)->as_Phi()->is_tripcount(bt))) {
342 return AddNode::make(phase->transform(SubNode::make(in1, in2->in(2), bt)), in2->in(1), bt);
343 }
344
345 // Associative
346 if (op1 == Op_Mul(bt) && op2 == Op_Mul(bt)) {
347 Node* add_in1 = nullptr;
348 Node* add_in2 = nullptr;
349 Node* mul_in = nullptr;
350
351 if (in1->in(1) == in2->in(1)) {
352 // Convert "a*b+a*c into a*(b+c)
353 add_in1 = in1->in(2);
354 add_in2 = in2->in(2);
355 mul_in = in1->in(1);
356 } else if (in1->in(2) == in2->in(1)) {
357 // Convert a*b+b*c into b*(a+c)
358 add_in1 = in1->in(1);
359 add_in2 = in2->in(2);
360 mul_in = in1->in(2);
361 } else if (in1->in(2) == in2->in(2)) {
362 // Convert a*c+b*c into (a+b)*c
363 add_in1 = in1->in(1);
364 add_in2 = in2->in(1);
365 mul_in = in1->in(2);
366 } else if (in1->in(1) == in2->in(2)) {
367 // Convert a*b+c*a into a*(b+c)
368 add_in1 = in1->in(2);
369 add_in2 = in2->in(1);
370 mul_in = in1->in(1);
371 }
372
373 if (mul_in != nullptr) {
374 Node* add = phase->transform(AddNode::make(add_in1, add_in2, bt));
375 return MulNode::make(mul_in, add, bt);
376 }
377 }
378
379 // Convert (x >>> rshift) + (x << lshift) into RotateRight(x, rshift)
380 if (Matcher::match_rule_supported(Op_RotateRight) &&
381 ((op1 == Op_URShift(bt) && op2 == Op_LShift(bt)) || (op1 == Op_LShift(bt) && op2 == Op_URShift(bt))) &&
382 in1->in(1) != nullptr && in1->in(1) == in2->in(1)) {
383 Node* rshift = op1 == Op_URShift(bt) ? in1->in(2) : in2->in(2);
384 Node* lshift = op1 == Op_URShift(bt) ? in2->in(2) : in1->in(2);
385 if (rshift != nullptr && lshift != nullptr) {
386 const TypeInt* rshift_t = phase->type(rshift)->isa_int();
387 const TypeInt* lshift_t = phase->type(lshift)->isa_int();
388 int bits = bt == T_INT ? 32 : 64;
389 int mask = bt == T_INT ? 0x1F : 0x3F;
390 if (lshift_t != nullptr && lshift_t->is_con() &&
391 rshift_t != nullptr && rshift_t->is_con() &&
392 ((lshift_t->get_con() & mask) == (bits - (rshift_t->get_con() & mask)))) {
393 return new RotateRightNode(in1->in(1), phase->intcon(rshift_t->get_con() & mask), TypeInteger::bottom(bt));
394 }
395 }
396 }
397
398 return AddNode::Ideal(phase, can_reshape);
399 }
400
401
402 Node* AddINode::Ideal(PhaseGVN* phase, bool can_reshape) {
403 Node* in1 = in(1);
404 Node* in2 = in(2);
405 int op1 = in1->Opcode();
406 int op2 = in2->Opcode();
407
408 // Convert (x>>>z)+y into (x+(y<<z))>>>z for small constant z and y.
409 // Helps with array allocation math constant folding
410 // See 4790063:
411 // Unrestricted transformation is unsafe for some runtime values of 'x'
412 // ( x == 0, z == 1, y == -1 ) fails
413 // ( x == -5, z == 1, y == 1 ) fails
414 // Transform works for small z and small negative y when the addition
415 // (x + (y << z)) does not cross zero.
416 // Implement support for negative y and (x >= -(y << z))
417 // Have not observed cases where type information exists to support
418 // positive y and (x <= -(y << z))
419 if (op1 == Op_URShiftI && op2 == Op_ConI &&
420 in1->in(2)->Opcode() == Op_ConI) {
421 jint z = phase->type(in1->in(2))->is_int()->get_con() & 0x1f; // only least significant 5 bits matter
422 jint y = phase->type(in2)->is_int()->get_con();
423
424 if (z < 5 && -5 < y && y < 0) {
425 const Type* t_in11 = phase->type(in1->in(1));
426 if( t_in11 != Type::TOP && (t_in11->is_int()->_lo >= -(y << z))) {
427 Node* a = phase->transform(new AddINode( in1->in(1), phase->intcon(y<<z)));
428 return new URShiftINode(a, in1->in(2));
429 }
430 }
431 }
432
433 return AddNode::IdealIL(phase, can_reshape, T_INT);
434 }
435
436
437 //------------------------------Identity---------------------------------------
438 // Fold (x-y)+y OR y+(x-y) into x
439 Node* AddINode::Identity(PhaseGVN* phase) {
440 if (in(1)->Opcode() == Op_SubI && in(1)->in(2) == in(2)) {
441 return in(1)->in(1);
442 } else if (in(2)->Opcode() == Op_SubI && in(2)->in(2) == in(1)) {
443 return in(2)->in(1);
444 }
445 return AddNode::Identity(phase);
446 }
447
448
449 //------------------------------add_ring---------------------------------------
450 // Supplied function returns the sum of the inputs. Guaranteed never
451 // to be passed a TOP or BOTTOM type, these are filtered out by
452 // pre-check.
453 const Type *AddINode::add_ring( const Type *t0, const Type *t1 ) const {
454 const TypeInt *r0 = t0->is_int(); // Handy access
455 const TypeInt *r1 = t1->is_int();
456 int lo = java_add(r0->_lo, r1->_lo);
457 int hi = java_add(r0->_hi, r1->_hi);
458 if( !(r0->is_con() && r1->is_con()) ) {
459 // Not both constants, compute approximate result
460 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
461 lo = min_jint; hi = max_jint; // Underflow on the low side
462 }
463 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
464 lo = min_jint; hi = max_jint; // Overflow on the high side
465 }
466 if( lo > hi ) { // Handle overflow
467 lo = min_jint; hi = max_jint;
468 }
469 } else {
470 // both constants, compute precise result using 'lo' and 'hi'
471 // Semantics define overflow and underflow for integer addition
472 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
473 }
474 return TypeInt::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
475 }
476
477
478 //=============================================================================
479 //------------------------------Idealize---------------------------------------
480 Node* AddLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
481 return AddNode::IdealIL(phase, can_reshape, T_LONG);
482 }
483
484
485 //------------------------------Identity---------------------------------------
486 // Fold (x-y)+y OR y+(x-y) into x
487 Node* AddLNode::Identity(PhaseGVN* phase) {
488 if (in(1)->Opcode() == Op_SubL && in(1)->in(2) == in(2)) {
489 return in(1)->in(1);
490 } else if (in(2)->Opcode() == Op_SubL && in(2)->in(2) == in(1)) {
491 return in(2)->in(1);
492 }
493 return AddNode::Identity(phase);
494 }
495
496
497 //------------------------------add_ring---------------------------------------
498 // Supplied function returns the sum of the inputs. Guaranteed never
499 // to be passed a TOP or BOTTOM type, these are filtered out by
500 // pre-check.
501 const Type *AddLNode::add_ring( const Type *t0, const Type *t1 ) const {
502 const TypeLong *r0 = t0->is_long(); // Handy access
503 const TypeLong *r1 = t1->is_long();
504 jlong lo = java_add(r0->_lo, r1->_lo);
505 jlong hi = java_add(r0->_hi, r1->_hi);
506 if( !(r0->is_con() && r1->is_con()) ) {
507 // Not both constants, compute approximate result
508 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
509 lo =min_jlong; hi = max_jlong; // Underflow on the low side
510 }
511 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
512 lo = min_jlong; hi = max_jlong; // Overflow on the high side
513 }
514 if( lo > hi ) { // Handle overflow
515 lo = min_jlong; hi = max_jlong;
516 }
517 } else {
518 // both constants, compute precise result using 'lo' and 'hi'
519 // Semantics define overflow and underflow for integer addition
520 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
521 }
522 return TypeLong::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
523 }
524
525
526 //=============================================================================
527 //------------------------------add_of_identity--------------------------------
528 // Check for addition of the identity
529 const Type *AddFNode::add_of_identity( const Type *t1, const Type *t2 ) const {
530 // x ADD 0 should return x unless 'x' is a -zero
531 //
532 // const Type *zero = add_id(); // The additive identity
533 // jfloat f1 = t1->getf();
534 // jfloat f2 = t2->getf();
535 //
536 // if( t1->higher_equal( zero ) ) return t2;
537 // if( t2->higher_equal( zero ) ) return t1;
538
539 return nullptr;
540 }
541
542 //------------------------------add_ring---------------------------------------
543 // Supplied function returns the sum of the inputs.
544 // This also type-checks the inputs for sanity. Guaranteed never to
545 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
546 const Type *AddFNode::add_ring( const Type *t0, const Type *t1 ) const {
547 if (!t0->isa_float_constant() || !t1->isa_float_constant()) {
548 return bottom_type();
549 }
550 return TypeF::make( t0->getf() + t1->getf() );
551 }
552
553 //------------------------------Ideal------------------------------------------
554 Node *AddFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
555 // Floating point additions are not associative because of boundary conditions (infinity)
556 return commute(phase, this) ? this : nullptr;
557 }
558
559
560 //=============================================================================
561 //------------------------------add_of_identity--------------------------------
562 // Check for addition of the identity
563 const Type *AddDNode::add_of_identity( const Type *t1, const Type *t2 ) const {
564 // x ADD 0 should return x unless 'x' is a -zero
565 //
566 // const Type *zero = add_id(); // The additive identity
567 // jfloat f1 = t1->getf();
568 // jfloat f2 = t2->getf();
569 //
570 // if( t1->higher_equal( zero ) ) return t2;
571 // if( t2->higher_equal( zero ) ) return t1;
572
573 return nullptr;
574 }
575 //------------------------------add_ring---------------------------------------
576 // Supplied function returns the sum of the inputs.
577 // This also type-checks the inputs for sanity. Guaranteed never to
578 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
579 const Type *AddDNode::add_ring( const Type *t0, const Type *t1 ) const {
580 if (!t0->isa_double_constant() || !t1->isa_double_constant()) {
581 return bottom_type();
582 }
583 return TypeD::make( t0->getd() + t1->getd() );
584 }
585
586 //------------------------------Ideal------------------------------------------
587 Node *AddDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
588 // Floating point additions are not associative because of boundary conditions (infinity)
589 return commute(phase, this) ? this : nullptr;
590 }
591
592
593 //=============================================================================
594 //------------------------------Identity---------------------------------------
595 // If one input is a constant 0, return the other input.
596 Node* AddPNode::Identity(PhaseGVN* phase) {
597 return ( phase->type( in(Offset) )->higher_equal( TypeX_ZERO ) ) ? in(Address) : this;
598 }
599
600 //------------------------------Idealize---------------------------------------
601 Node *AddPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
602 // Bail out if dead inputs
603 if( phase->type( in(Address) ) == Type::TOP ) return nullptr;
604
605 // If the left input is an add of a constant, flatten the expression tree.
606 const Node *n = in(Address);
607 if (n->is_AddP() && n->in(Base) == in(Base)) {
608 const AddPNode *addp = n->as_AddP(); // Left input is an AddP
609 assert( !addp->in(Address)->is_AddP() ||
610 addp->in(Address)->as_AddP() != addp,
611 "dead loop in AddPNode::Ideal" );
612 // Type of left input's right input
613 const Type *t = phase->type( addp->in(Offset) );
614 if( t == Type::TOP ) return nullptr;
615 const TypeX *t12 = t->is_intptr_t();
616 if( t12->is_con() ) { // Left input is an add of a constant?
617 // If the right input is a constant, combine constants
618 const Type *temp_t2 = phase->type( in(Offset) );
619 if( temp_t2 == Type::TOP ) return nullptr;
620 const TypeX *t2 = temp_t2->is_intptr_t();
621 Node* address;
622 Node* offset;
623 if( t2->is_con() ) {
624 // The Add of the flattened expression
625 address = addp->in(Address);
626 offset = phase->MakeConX(t2->get_con() + t12->get_con());
627 } else {
628 // Else move the constant to the right. ((A+con)+B) into ((A+B)+con)
629 address = phase->transform(new AddPNode(in(Base),addp->in(Address),in(Offset)));
630 offset = addp->in(Offset);
631 }
632 set_req_X(Address, address, phase);
633 set_req_X(Offset, offset, phase);
634 return this;
635 }
636 }
637
638 // Raw pointers?
639 if( in(Base)->bottom_type() == Type::TOP ) {
640 // If this is a null+long form (from unsafe accesses), switch to a rawptr.
641 if (phase->type(in(Address)) == TypePtr::NULL_PTR) {
642 Node* offset = in(Offset);
643 return new CastX2PNode(offset);
644 }
645 }
646
647 // If the right is an add of a constant, push the offset down.
648 // Convert: (ptr + (offset+con)) into (ptr+offset)+con.
649 // The idea is to merge array_base+scaled_index groups together,
650 // and only have different constant offsets from the same base.
651 const Node *add = in(Offset);
652 if( add->Opcode() == Op_AddX && add->in(1) != add ) {
653 const Type *t22 = phase->type( add->in(2) );
654 if( t22->singleton() && (t22 != Type::TOP) ) { // Right input is an add of a constant?
655 set_req(Address, phase->transform(new AddPNode(in(Base),in(Address),add->in(1))));
656 set_req_X(Offset, add->in(2), phase); // puts add on igvn worklist if needed
657 return this; // Made progress
658 }
659 }
660
661 return nullptr; // No progress
662 }
663
664 //------------------------------bottom_type------------------------------------
665 // Bottom-type is the pointer-type with unknown offset.
666 const Type *AddPNode::bottom_type() const {
667 if (in(Address) == nullptr) return TypePtr::BOTTOM;
668 const TypePtr *tp = in(Address)->bottom_type()->isa_ptr();
669 if( !tp ) return Type::TOP; // TOP input means TOP output
670 assert( in(Offset)->Opcode() != Op_ConP, "" );
671 const Type *t = in(Offset)->bottom_type();
672 if( t == Type::TOP )
673 return tp->add_offset(Type::OffsetTop);
674 const TypeX *tx = t->is_intptr_t();
675 intptr_t txoffset = Type::OffsetBot;
676 if (tx->is_con()) { // Left input is an add of a constant?
677 txoffset = tx->get_con();
678 }
679 if (tp->isa_aryptr()) {
680 // In the case of a flat inline type array, each field has its
681 // own slice so we need to extract the field being accessed from
682 // the address computation
683 return tp->is_aryptr()->add_field_offset_and_offset(txoffset);
684 }
685 return tp->add_offset(txoffset);
686 }
687
688 //------------------------------Value------------------------------------------
689 const Type* AddPNode::Value(PhaseGVN* phase) const {
690 // Either input is TOP ==> the result is TOP
691 const Type *t1 = phase->type( in(Address) );
692 const Type *t2 = phase->type( in(Offset) );
693 if( t1 == Type::TOP ) return Type::TOP;
694 if( t2 == Type::TOP ) return Type::TOP;
695
696 // Left input is a pointer
697 const TypePtr *p1 = t1->isa_ptr();
698 // Right input is an int
699 const TypeX *p2 = t2->is_intptr_t();
700 // Add 'em
701 intptr_t p2offset = Type::OffsetBot;
702 if (p2->is_con()) { // Left input is an add of a constant?
703 p2offset = p2->get_con();
704 }
705 if (p1->isa_aryptr()) {
706 // In the case of a flat inline type array, each field has its
707 // own slice so we need to extract the field being accessed from
708 // the address computation
709 return p1->is_aryptr()->add_field_offset_and_offset(p2offset);
710 }
711 return p1->add_offset(p2offset);
712 }
713
714 //------------------------Ideal_base_and_offset--------------------------------
715 // Split an oop pointer into a base and offset.
716 // (The offset might be Type::OffsetBot in the case of an array.)
717 // Return the base, or null if failure.
718 Node* AddPNode::Ideal_base_and_offset(Node* ptr, PhaseValues* phase,
719 // second return value:
720 intptr_t& offset) {
721 if (ptr->is_AddP()) {
722 Node* base = ptr->in(AddPNode::Base);
723 Node* addr = ptr->in(AddPNode::Address);
724 Node* offs = ptr->in(AddPNode::Offset);
725 if (base == addr || base->is_top()) {
726 offset = phase->find_intptr_t_con(offs, Type::OffsetBot);
727 if (offset != Type::OffsetBot) {
728 return addr;
729 }
730 }
731 }
732 offset = Type::OffsetBot;
733 return nullptr;
734 }
735
736 //------------------------------unpack_offsets----------------------------------
737 // Collect the AddP offset values into the elements array, giving up
738 // if there are more than length.
739 int AddPNode::unpack_offsets(Node* elements[], int length) const {
740 int count = 0;
741 Node const* addr = this;
742 Node* base = addr->in(AddPNode::Base);
743 while (addr->is_AddP()) {
744 if (addr->in(AddPNode::Base) != base) {
745 // give up
746 return -1;
747 }
748 elements[count++] = addr->in(AddPNode::Offset);
749 if (count == length) {
750 // give up
751 return -1;
752 }
753 addr = addr->in(AddPNode::Address);
754 }
755 if (addr != base) {
756 return -1;
757 }
758 return count;
759 }
760
761 //------------------------------match_edge-------------------------------------
762 // Do we Match on this edge index or not? Do not match base pointer edge
763 uint AddPNode::match_edge(uint idx) const {
764 return idx > Base;
765 }
766
767 //=============================================================================
768 //------------------------------Identity---------------------------------------
769 Node* OrINode::Identity(PhaseGVN* phase) {
770 // x | x => x
771 if (in(1) == in(2)) {
772 return in(1);
773 }
774
775 return AddNode::Identity(phase);
776 }
777
778 // Find shift value for Integer or Long OR.
779 static Node* rotate_shift(PhaseGVN* phase, Node* lshift, Node* rshift, int mask) {
780 // val << norm_con_shift | val >> ({32|64} - norm_con_shift) => rotate_left val, norm_con_shift
781 const TypeInt* lshift_t = phase->type(lshift)->isa_int();
782 const TypeInt* rshift_t = phase->type(rshift)->isa_int();
783 if (lshift_t != nullptr && lshift_t->is_con() &&
784 rshift_t != nullptr && rshift_t->is_con() &&
785 ((lshift_t->get_con() & mask) == ((mask + 1) - (rshift_t->get_con() & mask)))) {
786 return phase->intcon(lshift_t->get_con() & mask);
787 }
788 // val << var_shift | val >> ({0|32|64} - var_shift) => rotate_left val, var_shift
789 if (rshift->Opcode() == Op_SubI && rshift->in(2) == lshift && rshift->in(1)->is_Con()){
790 const TypeInt* shift_t = phase->type(rshift->in(1))->isa_int();
791 if (shift_t != nullptr && shift_t->is_con() &&
792 (shift_t->get_con() == 0 || shift_t->get_con() == (mask + 1))) {
793 return lshift;
794 }
795 }
796 return nullptr;
797 }
798
799 Node* OrINode::Ideal(PhaseGVN* phase, bool can_reshape) {
800 int lopcode = in(1)->Opcode();
801 int ropcode = in(2)->Opcode();
802 if (Matcher::match_rule_supported(Op_RotateLeft) &&
803 lopcode == Op_LShiftI && ropcode == Op_URShiftI && in(1)->in(1) == in(2)->in(1)) {
804 Node* lshift = in(1)->in(2);
805 Node* rshift = in(2)->in(2);
806 Node* shift = rotate_shift(phase, lshift, rshift, 0x1F);
807 if (shift != nullptr) {
808 return new RotateLeftNode(in(1)->in(1), shift, TypeInt::INT);
809 }
810 return nullptr;
811 }
812 if (Matcher::match_rule_supported(Op_RotateRight) &&
813 lopcode == Op_URShiftI && ropcode == Op_LShiftI && in(1)->in(1) == in(2)->in(1)) {
814 Node* rshift = in(1)->in(2);
815 Node* lshift = in(2)->in(2);
816 Node* shift = rotate_shift(phase, rshift, lshift, 0x1F);
817 if (shift != nullptr) {
818 return new RotateRightNode(in(1)->in(1), shift, TypeInt::INT);
819 }
820 }
821
822 // Convert "~a | ~b" into "~(a & b)"
823 if (AddNode::is_not(phase, in(1), T_INT) && AddNode::is_not(phase, in(2), T_INT)) {
824 Node* and_a_b = new AndINode(in(1)->in(1), in(2)->in(1));
825 Node* tn = phase->transform(and_a_b);
826 return AddNode::make_not(phase, tn, T_INT);
827 }
828 return nullptr;
829 }
830
831 //------------------------------add_ring---------------------------------------
832 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
833 // the logical operations the ring's ADD is really a logical OR function.
834 // This also type-checks the inputs for sanity. Guaranteed never to
835 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
836 const Type *OrINode::add_ring( const Type *t0, const Type *t1 ) const {
837 const TypeInt *r0 = t0->is_int(); // Handy access
838 const TypeInt *r1 = t1->is_int();
839
840 // If both args are bool, can figure out better types
841 if ( r0 == TypeInt::BOOL ) {
842 if ( r1 == TypeInt::ONE) {
843 return TypeInt::ONE;
844 } else if ( r1 == TypeInt::BOOL ) {
845 return TypeInt::BOOL;
846 }
847 } else if ( r0 == TypeInt::ONE ) {
848 if ( r1 == TypeInt::BOOL ) {
849 return TypeInt::ONE;
850 }
851 }
852
853 // If either input is not a constant, just return all integers.
854 if( !r0->is_con() || !r1->is_con() )
855 return TypeInt::INT; // Any integer, but still no symbols.
856
857 // Otherwise just OR them bits.
858 return TypeInt::make( r0->get_con() | r1->get_con() );
859 }
860
861 //=============================================================================
862 //------------------------------Identity---------------------------------------
863 Node* OrLNode::Identity(PhaseGVN* phase) {
864 // x | x => x
865 if (in(1) == in(2)) {
866 return in(1);
867 }
868
869 return AddNode::Identity(phase);
870 }
871
872 Node* OrLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
873 int lopcode = in(1)->Opcode();
874 int ropcode = in(2)->Opcode();
875 if (Matcher::match_rule_supported(Op_RotateLeft) &&
876 lopcode == Op_LShiftL && ropcode == Op_URShiftL && in(1)->in(1) == in(2)->in(1)) {
877 Node* lshift = in(1)->in(2);
878 Node* rshift = in(2)->in(2);
879 Node* shift = rotate_shift(phase, lshift, rshift, 0x3F);
880 if (shift != nullptr) {
881 return new RotateLeftNode(in(1)->in(1), shift, TypeLong::LONG);
882 }
883 return nullptr;
884 }
885 if (Matcher::match_rule_supported(Op_RotateRight) &&
886 lopcode == Op_URShiftL && ropcode == Op_LShiftL && in(1)->in(1) == in(2)->in(1)) {
887 Node* rshift = in(1)->in(2);
888 Node* lshift = in(2)->in(2);
889 Node* shift = rotate_shift(phase, rshift, lshift, 0x3F);
890 if (shift != nullptr) {
891 return new RotateRightNode(in(1)->in(1), shift, TypeLong::LONG);
892 }
893 }
894
895 // Convert "~a | ~b" into "~(a & b)"
896 if (AddNode::is_not(phase, in(1), T_LONG) && AddNode::is_not(phase, in(2), T_LONG)) {
897 Node* and_a_b = new AndLNode(in(1)->in(1), in(2)->in(1));
898 Node* tn = phase->transform(and_a_b);
899 return AddNode::make_not(phase, tn, T_LONG);
900 }
901
902 return nullptr;
903 }
904
905 //------------------------------add_ring---------------------------------------
906 const Type *OrLNode::add_ring( const Type *t0, const Type *t1 ) const {
907 const TypeLong *r0 = t0->is_long(); // Handy access
908 const TypeLong *r1 = t1->is_long();
909
910 // If either input is not a constant, just return all integers.
911 if( !r0->is_con() || !r1->is_con() )
912 return TypeLong::LONG; // Any integer, but still no symbols.
913
914 // Otherwise just OR them bits.
915 return TypeLong::make( r0->get_con() | r1->get_con() );
916 }
917
918 //---------------------------Helper -------------------------------------------
919 /* Decide if the given node is used only in arithmetic expressions(add or sub).
920 */
921 static bool is_used_in_only_arithmetic(Node* n, BasicType bt) {
922 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
923 Node* u = n->fast_out(i);
924 if (u->Opcode() != Op_Add(bt) && u->Opcode() != Op_Sub(bt)) {
925 return false;
926 }
927 }
928 return true;
929 }
930
931 //=============================================================================
932 //------------------------------Idealize---------------------------------------
933 Node* XorINode::Ideal(PhaseGVN* phase, bool can_reshape) {
934 Node* in1 = in(1);
935 Node* in2 = in(2);
936
937 // Convert ~x into -1-x when ~x is used in an arithmetic expression
938 // or x itself is an expression.
939 if (phase->type(in2) == TypeInt::MINUS_1) { // follows LHS^(-1), i.e., ~LHS
940 if (phase->is_IterGVN()) {
941 if (is_used_in_only_arithmetic(this, T_INT)
942 // LHS is arithmetic
943 || (in1->Opcode() == Op_AddI || in1->Opcode() == Op_SubI)) {
944 return new SubINode(in2, in1);
945 }
946 } else {
947 // graph could be incomplete in GVN so we postpone to IGVN
948 phase->record_for_igvn(this);
949 }
950 }
951
952 // Propagate xor through constant cmoves. This pattern can occur after expansion of Conv2B nodes.
953 const TypeInt* in2_type = phase->type(in2)->isa_int();
954 if (in1->Opcode() == Op_CMoveI && in2_type != nullptr && in2_type->is_con()) {
955 int in2_val = in2_type->get_con();
956
957 // Get types of both sides of the CMove
958 const TypeInt* left = phase->type(in1->in(CMoveNode::IfFalse))->isa_int();
959 const TypeInt* right = phase->type(in1->in(CMoveNode::IfTrue))->isa_int();
960
961 // Ensure that both sides are int constants
962 if (left != nullptr && right != nullptr && left->is_con() && right->is_con()) {
963 Node* cond = in1->in(CMoveNode::Condition);
964
965 // Check that the comparison is a bool and that the cmp node type is correct
966 if (cond->is_Bool()) {
967 int cmp_op = cond->in(1)->Opcode();
968
969 if (cmp_op == Op_CmpI || cmp_op == Op_CmpP) {
970 int l_val = left->get_con();
971 int r_val = right->get_con();
972
973 return new CMoveINode(cond, phase->intcon(l_val ^ in2_val), phase->intcon(r_val ^ in2_val), TypeInt::INT);
974 }
975 }
976 }
977 }
978
979 return AddNode::Ideal(phase, can_reshape);
980 }
981
982 const Type* XorINode::Value(PhaseGVN* phase) const {
983 Node* in1 = in(1);
984 Node* in2 = in(2);
985 const Type* t1 = phase->type(in1);
986 const Type* t2 = phase->type(in2);
987 if (t1 == Type::TOP || t2 == Type::TOP) {
988 return Type::TOP;
989 }
990 // x ^ x ==> 0
991 if (in1->eqv_uncast(in2)) {
992 return add_id();
993 }
994 // result of xor can only have bits sets where any of the
995 // inputs have bits set. lo can always become 0.
996 const TypeInt* t1i = t1->is_int();
997 const TypeInt* t2i = t2->is_int();
998 if ((t1i->_lo >= 0) &&
999 (t1i->_hi > 0) &&
1000 (t2i->_lo >= 0) &&
1001 (t2i->_hi > 0)) {
1002 // hi - set all bits below the highest bit. Using round_down to avoid overflow.
1003 const TypeInt* t1x = TypeInt::make(0, round_down_power_of_2(t1i->_hi) + (round_down_power_of_2(t1i->_hi) - 1), t1i->_widen);
1004 const TypeInt* t2x = TypeInt::make(0, round_down_power_of_2(t2i->_hi) + (round_down_power_of_2(t2i->_hi) - 1), t2i->_widen);
1005 return t1x->meet(t2x);
1006 }
1007 return AddNode::Value(phase);
1008 }
1009
1010
1011 //------------------------------add_ring---------------------------------------
1012 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
1013 // the logical operations the ring's ADD is really a logical OR function.
1014 // This also type-checks the inputs for sanity. Guaranteed never to
1015 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
1016 const Type *XorINode::add_ring( const Type *t0, const Type *t1 ) const {
1017 const TypeInt *r0 = t0->is_int(); // Handy access
1018 const TypeInt *r1 = t1->is_int();
1019
1020 // Complementing a boolean?
1021 if( r0 == TypeInt::BOOL && ( r1 == TypeInt::ONE
1022 || r1 == TypeInt::BOOL))
1023 return TypeInt::BOOL;
1024
1025 if( !r0->is_con() || !r1->is_con() ) // Not constants
1026 return TypeInt::INT; // Any integer, but still no symbols.
1027
1028 // Otherwise just XOR them bits.
1029 return TypeInt::make( r0->get_con() ^ r1->get_con() );
1030 }
1031
1032 //=============================================================================
1033 //------------------------------add_ring---------------------------------------
1034 const Type *XorLNode::add_ring( const Type *t0, const Type *t1 ) const {
1035 const TypeLong *r0 = t0->is_long(); // Handy access
1036 const TypeLong *r1 = t1->is_long();
1037
1038 // If either input is not a constant, just return all integers.
1039 if( !r0->is_con() || !r1->is_con() )
1040 return TypeLong::LONG; // Any integer, but still no symbols.
1041
1042 // Otherwise just OR them bits.
1043 return TypeLong::make( r0->get_con() ^ r1->get_con() );
1044 }
1045
1046 Node* XorLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1047 Node* in1 = in(1);
1048 Node* in2 = in(2);
1049
1050 // Convert ~x into -1-x when ~x is used in an arithmetic expression
1051 // or x itself is an arithmetic expression.
1052 if (phase->type(in2) == TypeLong::MINUS_1) { // follows LHS^(-1), i.e., ~LHS
1053 if (phase->is_IterGVN()) {
1054 if (is_used_in_only_arithmetic(this, T_LONG)
1055 // LHS is arithmetic
1056 || (in1->Opcode() == Op_AddL || in1->Opcode() == Op_SubL)) {
1057 return new SubLNode(in2, in1);
1058 }
1059 } else {
1060 // graph could be incomplete in GVN so we postpone to IGVN
1061 phase->record_for_igvn(this);
1062 }
1063 }
1064 return AddNode::Ideal(phase, can_reshape);
1065 }
1066
1067 const Type* XorLNode::Value(PhaseGVN* phase) const {
1068 Node* in1 = in(1);
1069 Node* in2 = in(2);
1070 const Type* t1 = phase->type(in1);
1071 const Type* t2 = phase->type(in2);
1072 if (t1 == Type::TOP || t2 == Type::TOP) {
1073 return Type::TOP;
1074 }
1075 // x ^ x ==> 0
1076 if (in1->eqv_uncast(in2)) {
1077 return add_id();
1078 }
1079 // result of xor can only have bits sets where any of the
1080 // inputs have bits set. lo can always become 0.
1081 const TypeLong* t1l = t1->is_long();
1082 const TypeLong* t2l = t2->is_long();
1083 if ((t1l->_lo >= 0) &&
1084 (t1l->_hi > 0) &&
1085 (t2l->_lo >= 0) &&
1086 (t2l->_hi > 0)) {
1087 // hi - set all bits below the highest bit. Using round_down to avoid overflow.
1088 const TypeLong* t1x = TypeLong::make(0, round_down_power_of_2(t1l->_hi) + (round_down_power_of_2(t1l->_hi) - 1), t1l->_widen);
1089 const TypeLong* t2x = TypeLong::make(0, round_down_power_of_2(t2l->_hi) + (round_down_power_of_2(t2l->_hi) - 1), t2l->_widen);
1090 return t1x->meet(t2x);
1091 }
1092 return AddNode::Value(phase);
1093 }
1094
1095 Node* MaxNode::build_min_max_int(Node* a, Node* b, bool is_max) {
1096 if (is_max) {
1097 return new MaxINode(a, b);
1098 } else {
1099 return new MinINode(a, b);
1100 }
1101 }
1102
1103 Node* MaxNode::build_min_max_long(PhaseGVN* phase, Node* a, Node* b, bool is_max) {
1104 if (is_max) {
1105 return new MaxLNode(phase->C, a, b);
1106 } else {
1107 return new MinLNode(phase->C, a, b);
1108 }
1109 }
1110
1111 Node* MaxNode::build_min_max(Node* a, Node* b, bool is_max, bool is_unsigned, const Type* t, PhaseGVN& gvn) {
1112 bool is_int = gvn.type(a)->isa_int();
1113 assert(is_int || gvn.type(a)->isa_long(), "int or long inputs");
1114 assert(is_int == (gvn.type(b)->isa_int() != nullptr), "inconsistent inputs");
1115 BasicType bt = is_int ? T_INT: T_LONG;
1116 Node* hook = nullptr;
1117 if (gvn.is_IterGVN()) {
1118 // Make sure a and b are not destroyed
1119 hook = new Node(2);
1120 hook->init_req(0, a);
1121 hook->init_req(1, b);
1122 }
1123 Node* res = nullptr;
1124 if (is_int && !is_unsigned) {
1125 res = gvn.transform(build_min_max_int(a, b, is_max));
1126 assert(gvn.type(res)->is_int()->_lo >= t->is_int()->_lo && gvn.type(res)->is_int()->_hi <= t->is_int()->_hi, "type doesn't match");
1127 } else {
1128 Node* cmp = nullptr;
1129 if (is_max) {
1130 cmp = gvn.transform(CmpNode::make(a, b, bt, is_unsigned));
1131 } else {
1132 cmp = gvn.transform(CmpNode::make(b, a, bt, is_unsigned));
1133 }
1134 Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::lt));
1135 res = gvn.transform(CMoveNode::make(nullptr, bol, a, b, t));
1136 }
1137 if (hook != nullptr) {
1138 hook->destruct(&gvn);
1139 }
1140 return res;
1141 }
1142
1143 Node* MaxNode::build_min_max_diff_with_zero(Node* a, Node* b, bool is_max, const Type* t, PhaseGVN& gvn) {
1144 bool is_int = gvn.type(a)->isa_int();
1145 assert(is_int || gvn.type(a)->isa_long(), "int or long inputs");
1146 assert(is_int == (gvn.type(b)->isa_int() != nullptr), "inconsistent inputs");
1147 BasicType bt = is_int ? T_INT: T_LONG;
1148 Node* zero = gvn.integercon(0, bt);
1149 Node* hook = nullptr;
1150 if (gvn.is_IterGVN()) {
1151 // Make sure a and b are not destroyed
1152 hook = new Node(2);
1153 hook->init_req(0, a);
1154 hook->init_req(1, b);
1155 }
1156 Node* cmp = nullptr;
1157 if (is_max) {
1158 cmp = gvn.transform(CmpNode::make(a, b, bt, false));
1159 } else {
1160 cmp = gvn.transform(CmpNode::make(b, a, bt, false));
1161 }
1162 Node* sub = gvn.transform(SubNode::make(a, b, bt));
1163 Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::lt));
1164 Node* res = gvn.transform(CMoveNode::make(nullptr, bol, sub, zero, t));
1165 if (hook != nullptr) {
1166 hook->destruct(&gvn);
1167 }
1168 return res;
1169 }
1170
1171 // Check if addition of an integer with type 't' and a constant 'c' can overflow.
1172 static bool can_overflow(const TypeInt* t, jint c) {
1173 jint t_lo = t->_lo;
1174 jint t_hi = t->_hi;
1175 return ((c < 0 && (java_add(t_lo, c) > t_lo)) ||
1176 (c > 0 && (java_add(t_hi, c) < t_hi)));
1177 }
1178
1179 // Let <x, x_off> = x_operands and <y, y_off> = y_operands.
1180 // If x == y and neither add(x, x_off) nor add(y, y_off) overflow, return
1181 // add(x, op(x_off, y_off)). Otherwise, return nullptr.
1182 Node* MaxNode::extract_add(PhaseGVN* phase, ConstAddOperands x_operands, ConstAddOperands y_operands) {
1183 Node* x = x_operands.first;
1184 Node* y = y_operands.first;
1185 int opcode = Opcode();
1186 assert(opcode == Op_MaxI || opcode == Op_MinI, "Unexpected opcode");
1187 const TypeInt* tx = phase->type(x)->isa_int();
1188 jint x_off = x_operands.second;
1189 jint y_off = y_operands.second;
1190 if (x == y && tx != nullptr &&
1191 !can_overflow(tx, x_off) &&
1192 !can_overflow(tx, y_off)) {
1193 jint c = opcode == Op_MinI ? MIN2(x_off, y_off) : MAX2(x_off, y_off);
1194 return new AddINode(x, phase->intcon(c));
1195 }
1196 return nullptr;
1197 }
1198
1199 // Try to cast n as an integer addition with a constant. Return:
1200 // <x, C>, if n == add(x, C), where 'C' is a non-TOP constant;
1201 // <nullptr, 0>, if n == add(x, C), where 'C' is a TOP constant; or
1202 // <n, 0>, otherwise.
1203 static ConstAddOperands as_add_with_constant(Node* n) {
1204 if (n->Opcode() != Op_AddI) {
1205 return ConstAddOperands(n, 0);
1206 }
1207 Node* x = n->in(1);
1208 Node* c = n->in(2);
1209 if (!c->is_Con()) {
1210 return ConstAddOperands(n, 0);
1211 }
1212 const Type* c_type = c->bottom_type();
1213 if (c_type == Type::TOP) {
1214 return ConstAddOperands(nullptr, 0);
1215 }
1216 return ConstAddOperands(x, c_type->is_int()->get_con());
1217 }
1218
1219 Node* MaxNode::IdealI(PhaseGVN* phase, bool can_reshape) {
1220 int opcode = Opcode();
1221 assert(opcode == Op_MinI || opcode == Op_MaxI, "Unexpected opcode");
1222 // Try to transform the following pattern, in any of its four possible
1223 // permutations induced by op's commutativity:
1224 // op(op(add(inner, inner_off), inner_other), add(outer, outer_off))
1225 // into
1226 // op(add(inner, op(inner_off, outer_off)), inner_other),
1227 // where:
1228 // op is either MinI or MaxI, and
1229 // inner == outer, and
1230 // the additions cannot overflow.
1231 for (uint inner_op_index = 1; inner_op_index <= 2; inner_op_index++) {
1232 if (in(inner_op_index)->Opcode() != opcode) {
1233 continue;
1234 }
1235 Node* outer_add = in(inner_op_index == 1 ? 2 : 1);
1236 ConstAddOperands outer_add_operands = as_add_with_constant(outer_add);
1237 if (outer_add_operands.first == nullptr) {
1238 return nullptr; // outer_add has a TOP input, no need to continue.
1239 }
1240 // One operand is a MinI/MaxI and the other is an integer addition with
1241 // constant. Test the operands of the inner MinI/MaxI.
1242 for (uint inner_add_index = 1; inner_add_index <= 2; inner_add_index++) {
1243 Node* inner_op = in(inner_op_index);
1244 Node* inner_add = inner_op->in(inner_add_index);
1245 ConstAddOperands inner_add_operands = as_add_with_constant(inner_add);
1246 if (inner_add_operands.first == nullptr) {
1247 return nullptr; // inner_add has a TOP input, no need to continue.
1248 }
1249 // Try to extract the inner add.
1250 Node* add_extracted = extract_add(phase, inner_add_operands, outer_add_operands);
1251 if (add_extracted == nullptr) {
1252 continue;
1253 }
1254 Node* add_transformed = phase->transform(add_extracted);
1255 Node* inner_other = inner_op->in(inner_add_index == 1 ? 2 : 1);
1256 return build_min_max_int(add_transformed, inner_other, opcode == Op_MaxI);
1257 }
1258 }
1259 // Try to transform
1260 // op(add(x, x_off), add(y, y_off))
1261 // into
1262 // add(x, op(x_off, y_off)),
1263 // where:
1264 // op is either MinI or MaxI, and
1265 // inner == outer, and
1266 // the additions cannot overflow.
1267 ConstAddOperands xC = as_add_with_constant(in(1));
1268 ConstAddOperands yC = as_add_with_constant(in(2));
1269 if (xC.first == nullptr || yC.first == nullptr) return nullptr;
1270 return extract_add(phase, xC, yC);
1271 }
1272
1273 // Ideal transformations for MaxINode
1274 Node* MaxINode::Ideal(PhaseGVN* phase, bool can_reshape) {
1275 return IdealI(phase, can_reshape);
1276 }
1277
1278 //=============================================================================
1279 //------------------------------add_ring---------------------------------------
1280 // Supplied function returns the sum of the inputs.
1281 const Type *MaxINode::add_ring( const Type *t0, const Type *t1 ) const {
1282 const TypeInt *r0 = t0->is_int(); // Handy access
1283 const TypeInt *r1 = t1->is_int();
1284
1285 // Otherwise just MAX them bits.
1286 return TypeInt::make( MAX2(r0->_lo,r1->_lo), MAX2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
1287 }
1288
1289 //=============================================================================
1290 //------------------------------Idealize---------------------------------------
1291 // MINs show up in range-check loop limit calculations. Look for
1292 // "MIN2(x+c0,MIN2(y,x+c1))". Pick the smaller constant: "MIN2(x+c0,y)"
1293 Node* MinINode::Ideal(PhaseGVN* phase, bool can_reshape) {
1294 return IdealI(phase, can_reshape);
1295 }
1296
1297 //------------------------------add_ring---------------------------------------
1298 // Supplied function returns the sum of the inputs.
1299 const Type *MinINode::add_ring( const Type *t0, const Type *t1 ) const {
1300 const TypeInt *r0 = t0->is_int(); // Handy access
1301 const TypeInt *r1 = t1->is_int();
1302
1303 // Otherwise just MIN them bits.
1304 return TypeInt::make( MIN2(r0->_lo,r1->_lo), MIN2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
1305 }
1306
1307 // Collapse the "addition with overflow-protection" pattern, and the symmetrical
1308 // "subtraction with underflow-protection" pattern. These are created during the
1309 // unrolling, when we have to adjust the limit by subtracting the stride, but want
1310 // to protect against underflow: MaxL(SubL(limit, stride), min_jint).
1311 // If we have more than one of those in a sequence:
1312 //
1313 // x con2
1314 // | |
1315 // AddL clamp2
1316 // | |
1317 // Max/MinL con1
1318 // | |
1319 // AddL clamp1
1320 // | |
1321 // Max/MinL (n)
1322 //
1323 // We want to collapse it to:
1324 //
1325 // x con1 con2
1326 // | | |
1327 // | AddLNode (new_con)
1328 // | |
1329 // AddLNode clamp1
1330 // | |
1331 // Max/MinL (n)
1332 //
1333 // Note: we assume that SubL was already replaced by an AddL, and that the stride
1334 // has its sign flipped: SubL(limit, stride) -> AddL(limit, -stride).
1335 static Node* fold_subI_no_underflow_pattern(Node* n, PhaseGVN* phase) {
1336 assert(n->Opcode() == Op_MaxL || n->Opcode() == Op_MinL, "sanity");
1337 // Check that the two clamps have the correct values.
1338 jlong clamp = (n->Opcode() == Op_MaxL) ? min_jint : max_jint;
1339 auto is_clamp = [&](Node* c) {
1340 const TypeLong* t = phase->type(c)->isa_long();
1341 return t != nullptr && t->is_con() &&
1342 t->get_con() == clamp;
1343 };
1344 // Check that the constants are negative if MaxL, and positive if MinL.
1345 auto is_sub_con = [&](Node* c) {
1346 const TypeLong* t = phase->type(c)->isa_long();
1347 return t != nullptr && t->is_con() &&
1348 t->get_con() < max_jint && t->get_con() > min_jint &&
1349 (t->get_con() < 0) == (n->Opcode() == Op_MaxL);
1350 };
1351 // Verify the graph level by level:
1352 Node* add1 = n->in(1);
1353 Node* clamp1 = n->in(2);
1354 if (add1->Opcode() == Op_AddL && is_clamp(clamp1)) {
1355 Node* max2 = add1->in(1);
1356 Node* con1 = add1->in(2);
1357 if (max2->Opcode() == n->Opcode() && is_sub_con(con1)) {
1358 Node* add2 = max2->in(1);
1359 Node* clamp2 = max2->in(2);
1360 if (add2->Opcode() == Op_AddL && is_clamp(clamp2)) {
1361 Node* x = add2->in(1);
1362 Node* con2 = add2->in(2);
1363 if (is_sub_con(con2)) {
1364 Node* new_con = phase->transform(new AddLNode(con1, con2));
1365 Node* new_sub = phase->transform(new AddLNode(x, new_con));
1366 n->set_req_X(1, new_sub, phase);
1367 return n;
1368 }
1369 }
1370 }
1371 }
1372 return nullptr;
1373 }
1374
1375 const Type* MaxLNode::add_ring(const Type* t0, const Type* t1) const {
1376 const TypeLong* r0 = t0->is_long();
1377 const TypeLong* r1 = t1->is_long();
1378
1379 return TypeLong::make(MAX2(r0->_lo, r1->_lo), MAX2(r0->_hi, r1->_hi), MAX2(r0->_widen, r1->_widen));
1380 }
1381
1382 Node* MaxLNode::Identity(PhaseGVN* phase) {
1383 const TypeLong* t1 = phase->type(in(1))->is_long();
1384 const TypeLong* t2 = phase->type(in(2))->is_long();
1385
1386 // Can we determine maximum statically?
1387 if (t1->_lo >= t2->_hi) {
1388 return in(1);
1389 } else if (t2->_lo >= t1->_hi) {
1390 return in(2);
1391 }
1392
1393 return MaxNode::Identity(phase);
1394 }
1395
1396 Node* MaxLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1397 Node* n = AddNode::Ideal(phase, can_reshape);
1398 if (n != nullptr) {
1399 return n;
1400 }
1401 if (can_reshape) {
1402 return fold_subI_no_underflow_pattern(this, phase);
1403 }
1404 return nullptr;
1405 }
1406
1407 const Type* MinLNode::add_ring(const Type* t0, const Type* t1) const {
1408 const TypeLong* r0 = t0->is_long();
1409 const TypeLong* r1 = t1->is_long();
1410
1411 return TypeLong::make(MIN2(r0->_lo, r1->_lo), MIN2(r0->_hi, r1->_hi), MIN2(r0->_widen, r1->_widen));
1412 }
1413
1414 Node* MinLNode::Identity(PhaseGVN* phase) {
1415 const TypeLong* t1 = phase->type(in(1))->is_long();
1416 const TypeLong* t2 = phase->type(in(2))->is_long();
1417
1418 // Can we determine minimum statically?
1419 if (t1->_lo >= t2->_hi) {
1420 return in(2);
1421 } else if (t2->_lo >= t1->_hi) {
1422 return in(1);
1423 }
1424
1425 return MaxNode::Identity(phase);
1426 }
1427
1428 Node* MinLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1429 Node* n = AddNode::Ideal(phase, can_reshape);
1430 if (n != nullptr) {
1431 return n;
1432 }
1433 if (can_reshape) {
1434 return fold_subI_no_underflow_pattern(this, phase);
1435 }
1436 return nullptr;
1437 }
1438
1439 Node* MaxNode::Identity(PhaseGVN* phase) {
1440 if (in(1) == in(2)) {
1441 return in(1);
1442 }
1443
1444 return AddNode::Identity(phase);
1445 }
1446
1447 //------------------------------add_ring---------------------------------------
1448 const Type* MinFNode::add_ring(const Type* t0, const Type* t1 ) const {
1449 const TypeF* r0 = t0->isa_float_constant();
1450 const TypeF* r1 = t1->isa_float_constant();
1451 if (r0 == nullptr || r1 == nullptr) {
1452 return bottom_type();
1453 }
1454
1455 if (r0->is_nan()) {
1456 return r0;
1457 }
1458 if (r1->is_nan()) {
1459 return r1;
1460 }
1461
1462 float f0 = r0->getf();
1463 float f1 = r1->getf();
1464 if (f0 != 0.0f || f1 != 0.0f) {
1465 return f0 < f1 ? r0 : r1;
1466 }
1467
1468 // handle min of 0.0, -0.0 case.
1469 return (jint_cast(f0) < jint_cast(f1)) ? r0 : r1;
1470 }
1471
1472 //------------------------------add_ring---------------------------------------
1473 const Type* MinDNode::add_ring(const Type* t0, const Type* t1) const {
1474 const TypeD* r0 = t0->isa_double_constant();
1475 const TypeD* r1 = t1->isa_double_constant();
1476 if (r0 == nullptr || r1 == nullptr) {
1477 return bottom_type();
1478 }
1479
1480 if (r0->is_nan()) {
1481 return r0;
1482 }
1483 if (r1->is_nan()) {
1484 return r1;
1485 }
1486
1487 double d0 = r0->getd();
1488 double d1 = r1->getd();
1489 if (d0 != 0.0 || d1 != 0.0) {
1490 return d0 < d1 ? r0 : r1;
1491 }
1492
1493 // handle min of 0.0, -0.0 case.
1494 return (jlong_cast(d0) < jlong_cast(d1)) ? r0 : r1;
1495 }
1496
1497 //------------------------------add_ring---------------------------------------
1498 const Type* MaxFNode::add_ring(const Type* t0, const Type* t1) const {
1499 const TypeF* r0 = t0->isa_float_constant();
1500 const TypeF* r1 = t1->isa_float_constant();
1501 if (r0 == nullptr || r1 == nullptr) {
1502 return bottom_type();
1503 }
1504
1505 if (r0->is_nan()) {
1506 return r0;
1507 }
1508 if (r1->is_nan()) {
1509 return r1;
1510 }
1511
1512 float f0 = r0->getf();
1513 float f1 = r1->getf();
1514 if (f0 != 0.0f || f1 != 0.0f) {
1515 return f0 > f1 ? r0 : r1;
1516 }
1517
1518 // handle max of 0.0,-0.0 case.
1519 return (jint_cast(f0) > jint_cast(f1)) ? r0 : r1;
1520 }
1521
1522 //------------------------------add_ring---------------------------------------
1523 const Type* MaxDNode::add_ring(const Type* t0, const Type* t1) const {
1524 const TypeD* r0 = t0->isa_double_constant();
1525 const TypeD* r1 = t1->isa_double_constant();
1526 if (r0 == nullptr || r1 == nullptr) {
1527 return bottom_type();
1528 }
1529
1530 if (r0->is_nan()) {
1531 return r0;
1532 }
1533 if (r1->is_nan()) {
1534 return r1;
1535 }
1536
1537 double d0 = r0->getd();
1538 double d1 = r1->getd();
1539 if (d0 != 0.0 || d1 != 0.0) {
1540 return d0 > d1 ? r0 : r1;
1541 }
1542
1543 // handle max of 0.0, -0.0 case.
1544 return (jlong_cast(d0) > jlong_cast(d1)) ? r0 : r1;
1545 }