1 /*
2 * Copyright (c) 1997, 2023, 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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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
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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 //=============================================================================
257 //------------------------------Idealize---------------------------------------
258 Node* AddNode::IdealIL(PhaseGVN* phase, bool can_reshape, BasicType bt) {
259 Node* in1 = in(1);
260 Node* in2 = in(2);
261 int op1 = in1->Opcode();
262 int op2 = in2->Opcode();
263 // Fold (con1-x)+con2 into (con1+con2)-x
264 if (op1 == Op_Add(bt) && op2 == Op_Sub(bt)) {
265 // Swap edges to try optimizations below
266 in1 = in2;
267 in2 = in(1);
268 op1 = op2;
269 op2 = in2->Opcode();
270 }
271 if (op1 == Op_Sub(bt)) {
272 const Type* t_sub1 = phase->type(in1->in(1));
273 const Type* t_2 = phase->type(in2 );
274 if (t_sub1->singleton() && t_2->singleton() && t_sub1 != Type::TOP && t_2 != Type::TOP) {
275 return SubNode::make(phase->makecon(add_ring(t_sub1, t_2)), in1->in(2), bt);
276 }
277 // Convert "(a-b)+(c-d)" into "(a+c)-(b+d)"
278 if (op2 == Op_Sub(bt)) {
279 // Check for dead cycle: d = (a-b)+(c-d)
280 assert( in1->in(2) != this && in2->in(2) != this,
281 "dead loop in AddINode::Ideal" );
282 Node* sub = SubNode::make(nullptr, nullptr, bt);
283 sub->init_req(1, phase->transform(AddNode::make(in1->in(1), in2->in(1), bt)));
284 sub->init_req(2, phase->transform(AddNode::make(in1->in(2), in2->in(2), bt)));
285 return sub;
286 }
287 // Convert "(a-b)+(b+c)" into "(a+c)"
288 if (op2 == Op_Add(bt) && in1->in(2) == in2->in(1)) {
289 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddINode::Ideal/AddLNode::Ideal");
290 return AddNode::make(in1->in(1), in2->in(2), bt);
291 }
292 // Convert "(a-b)+(c+b)" into "(a+c)"
293 if (op2 == Op_Add(bt) && in1->in(2) == in2->in(2)) {
294 assert(in1->in(1) != this && in2->in(1) != this,"dead loop in AddINode::Ideal/AddLNode::Ideal");
295 return AddNode::make(in1->in(1), in2->in(1), bt);
296 }
297 }
298
299 // Convert (con - y) + x into "(x - y) + con"
300 if (op1 == Op_Sub(bt) && in1->in(1)->Opcode() == Op_ConIL(bt)
301 && in1 != in1->in(2) && !(in1->in(2)->is_Phi() && in1->in(2)->as_Phi()->is_tripcount(bt))) {
302 return AddNode::make(phase->transform(SubNode::make(in2, in1->in(2), bt)), in1->in(1), bt);
303 }
304
305 // Convert x + (con - y) into "(x - y) + con"
306 if (op2 == Op_Sub(bt) && in2->in(1)->Opcode() == Op_ConIL(bt)
307 && in2 != in2->in(2) && !(in2->in(2)->is_Phi() && in2->in(2)->as_Phi()->is_tripcount(bt))) {
308 return AddNode::make(phase->transform(SubNode::make(in1, in2->in(2), bt)), in2->in(1), bt);
309 }
310
311 // Associative
312 if (op1 == Op_Mul(bt) && op2 == Op_Mul(bt)) {
313 Node* add_in1 = nullptr;
314 Node* add_in2 = nullptr;
315 Node* mul_in = nullptr;
316
317 if (in1->in(1) == in2->in(1)) {
318 // Convert "a*b+a*c into a*(b+c)
319 add_in1 = in1->in(2);
320 add_in2 = in2->in(2);
321 mul_in = in1->in(1);
322 } else if (in1->in(2) == in2->in(1)) {
323 // Convert a*b+b*c into b*(a+c)
324 add_in1 = in1->in(1);
325 add_in2 = in2->in(2);
326 mul_in = in1->in(2);
327 } else if (in1->in(2) == in2->in(2)) {
328 // Convert a*c+b*c into (a+b)*c
329 add_in1 = in1->in(1);
330 add_in2 = in2->in(1);
331 mul_in = in1->in(2);
332 } else if (in1->in(1) == in2->in(2)) {
333 // Convert a*b+c*a into a*(b+c)
334 add_in1 = in1->in(2);
335 add_in2 = in2->in(1);
336 mul_in = in1->in(1);
337 }
338
339 if (mul_in != nullptr) {
340 Node* add = phase->transform(AddNode::make(add_in1, add_in2, bt));
341 return MulNode::make(mul_in, add, bt);
342 }
343 }
344
345 // Convert (x >>> rshift) + (x << lshift) into RotateRight(x, rshift)
346 if (Matcher::match_rule_supported(Op_RotateRight) &&
347 ((op1 == Op_URShift(bt) && op2 == Op_LShift(bt)) || (op1 == Op_LShift(bt) && op2 == Op_URShift(bt))) &&
348 in1->in(1) != nullptr && in1->in(1) == in2->in(1)) {
349 Node* rshift = op1 == Op_URShift(bt) ? in1->in(2) : in2->in(2);
350 Node* lshift = op1 == Op_URShift(bt) ? in2->in(2) : in1->in(2);
351 if (rshift != nullptr && lshift != nullptr) {
352 const TypeInt* rshift_t = phase->type(rshift)->isa_int();
353 const TypeInt* lshift_t = phase->type(lshift)->isa_int();
354 int bits = bt == T_INT ? 32 : 64;
355 int mask = bt == T_INT ? 0x1F : 0x3F;
356 if (lshift_t != nullptr && lshift_t->is_con() &&
357 rshift_t != nullptr && rshift_t->is_con() &&
358 ((lshift_t->get_con() & mask) == (bits - (rshift_t->get_con() & mask)))) {
359 return new RotateRightNode(in1->in(1), phase->intcon(rshift_t->get_con() & mask), TypeInteger::bottom(bt));
360 }
361 }
362 }
363
364 return AddNode::Ideal(phase, can_reshape);
365 }
366
367
368 Node* AddINode::Ideal(PhaseGVN* phase, bool can_reshape) {
369 Node* in1 = in(1);
370 Node* in2 = in(2);
371 int op1 = in1->Opcode();
372 int op2 = in2->Opcode();
373
374 // Convert (x>>>z)+y into (x+(y<<z))>>>z for small constant z and y.
375 // Helps with array allocation math constant folding
376 // See 4790063:
377 // Unrestricted transformation is unsafe for some runtime values of 'x'
378 // ( x == 0, z == 1, y == -1 ) fails
379 // ( x == -5, z == 1, y == 1 ) fails
380 // Transform works for small z and small negative y when the addition
381 // (x + (y << z)) does not cross zero.
382 // Implement support for negative y and (x >= -(y << z))
383 // Have not observed cases where type information exists to support
384 // positive y and (x <= -(y << z))
385 if (op1 == Op_URShiftI && op2 == Op_ConI &&
386 in1->in(2)->Opcode() == Op_ConI) {
387 jint z = phase->type(in1->in(2))->is_int()->get_con() & 0x1f; // only least significant 5 bits matter
388 jint y = phase->type(in2)->is_int()->get_con();
389
390 if (z < 5 && -5 < y && y < 0) {
391 const Type* t_in11 = phase->type(in1->in(1));
392 if( t_in11 != Type::TOP && (t_in11->is_int()->_lo >= -(y << z))) {
393 Node* a = phase->transform(new AddINode( in1->in(1), phase->intcon(y<<z)));
394 return new URShiftINode(a, in1->in(2));
395 }
396 }
397 }
398
399 return AddNode::IdealIL(phase, can_reshape, T_INT);
400 }
401
402
403 //------------------------------Identity---------------------------------------
404 // Fold (x-y)+y OR y+(x-y) into x
405 Node* AddINode::Identity(PhaseGVN* phase) {
406 if (in(1)->Opcode() == Op_SubI && in(1)->in(2) == in(2)) {
407 return in(1)->in(1);
408 } else if (in(2)->Opcode() == Op_SubI && in(2)->in(2) == in(1)) {
409 return in(2)->in(1);
410 }
411 return AddNode::Identity(phase);
412 }
413
414
415 //------------------------------add_ring---------------------------------------
416 // Supplied function returns the sum of the inputs. Guaranteed never
417 // to be passed a TOP or BOTTOM type, these are filtered out by
418 // pre-check.
419 const Type *AddINode::add_ring( const Type *t0, const Type *t1 ) const {
420 const TypeInt *r0 = t0->is_int(); // Handy access
421 const TypeInt *r1 = t1->is_int();
422 int lo = java_add(r0->_lo, r1->_lo);
423 int hi = java_add(r0->_hi, r1->_hi);
424 if( !(r0->is_con() && r1->is_con()) ) {
425 // Not both constants, compute approximate result
426 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
427 lo = min_jint; hi = max_jint; // Underflow on the low side
428 }
429 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
430 lo = min_jint; hi = max_jint; // Overflow on the high side
431 }
432 if( lo > hi ) { // Handle overflow
433 lo = min_jint; hi = max_jint;
434 }
435 } else {
436 // both constants, compute precise result using 'lo' and 'hi'
437 // Semantics define overflow and underflow for integer addition
438 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
439 }
440 return TypeInt::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
441 }
442
443
444 //=============================================================================
445 //------------------------------Idealize---------------------------------------
446 Node* AddLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
447 return AddNode::IdealIL(phase, can_reshape, T_LONG);
448 }
449
450
451 //------------------------------Identity---------------------------------------
452 // Fold (x-y)+y OR y+(x-y) into x
453 Node* AddLNode::Identity(PhaseGVN* phase) {
454 if (in(1)->Opcode() == Op_SubL && in(1)->in(2) == in(2)) {
455 return in(1)->in(1);
456 } else if (in(2)->Opcode() == Op_SubL && in(2)->in(2) == in(1)) {
457 return in(2)->in(1);
458 }
459 return AddNode::Identity(phase);
460 }
461
462
463 //------------------------------add_ring---------------------------------------
464 // Supplied function returns the sum of the inputs. Guaranteed never
465 // to be passed a TOP or BOTTOM type, these are filtered out by
466 // pre-check.
467 const Type *AddLNode::add_ring( const Type *t0, const Type *t1 ) const {
468 const TypeLong *r0 = t0->is_long(); // Handy access
469 const TypeLong *r1 = t1->is_long();
470 jlong lo = java_add(r0->_lo, r1->_lo);
471 jlong hi = java_add(r0->_hi, r1->_hi);
472 if( !(r0->is_con() && r1->is_con()) ) {
473 // Not both constants, compute approximate result
474 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
475 lo =min_jlong; hi = max_jlong; // Underflow on the low side
476 }
477 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
478 lo = min_jlong; hi = max_jlong; // Overflow on the high side
479 }
480 if( lo > hi ) { // Handle overflow
481 lo = min_jlong; hi = max_jlong;
482 }
483 } else {
484 // both constants, compute precise result using 'lo' and 'hi'
485 // Semantics define overflow and underflow for integer addition
486 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
487 }
488 return TypeLong::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
489 }
490
491
492 //=============================================================================
493 //------------------------------add_of_identity--------------------------------
494 // Check for addition of the identity
495 const Type *AddFNode::add_of_identity( const Type *t1, const Type *t2 ) const {
496 // x ADD 0 should return x unless 'x' is a -zero
497 //
498 // const Type *zero = add_id(); // The additive identity
499 // jfloat f1 = t1->getf();
500 // jfloat f2 = t2->getf();
501 //
502 // if( t1->higher_equal( zero ) ) return t2;
503 // if( t2->higher_equal( zero ) ) return t1;
504
505 return nullptr;
506 }
507
508 //------------------------------add_ring---------------------------------------
509 // Supplied function returns the sum of the inputs.
510 // This also type-checks the inputs for sanity. Guaranteed never to
511 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
512 const Type *AddFNode::add_ring( const Type *t0, const Type *t1 ) const {
513 if (!t0->isa_float_constant() || !t1->isa_float_constant()) {
514 return bottom_type();
515 }
516 return TypeF::make( t0->getf() + t1->getf() );
517 }
518
519 //------------------------------Ideal------------------------------------------
520 Node *AddFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
521 // Floating point additions are not associative because of boundary conditions (infinity)
522 return commute(phase, this) ? this : nullptr;
523 }
524
525
526 //=============================================================================
527 //------------------------------add_of_identity--------------------------------
528 // Check for addition of the identity
529 const Type *AddDNode::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 //------------------------------add_ring---------------------------------------
542 // Supplied function returns the sum of the inputs.
543 // This also type-checks the inputs for sanity. Guaranteed never to
544 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
545 const Type *AddDNode::add_ring( const Type *t0, const Type *t1 ) const {
546 if (!t0->isa_double_constant() || !t1->isa_double_constant()) {
547 return bottom_type();
548 }
549 return TypeD::make( t0->getd() + t1->getd() );
550 }
551
552 //------------------------------Ideal------------------------------------------
553 Node *AddDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
554 // Floating point additions are not associative because of boundary conditions (infinity)
555 return commute(phase, this) ? this : nullptr;
556 }
557
558
559 //=============================================================================
560 //------------------------------Identity---------------------------------------
561 // If one input is a constant 0, return the other input.
562 Node* AddPNode::Identity(PhaseGVN* phase) {
563 return ( phase->type( in(Offset) )->higher_equal( TypeX_ZERO ) ) ? in(Address) : this;
564 }
565
566 //------------------------------Idealize---------------------------------------
567 Node *AddPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
568 // Bail out if dead inputs
569 if( phase->type( in(Address) ) == Type::TOP ) return nullptr;
570
571 // If the left input is an add of a constant, flatten the expression tree.
572 const Node *n = in(Address);
573 if (n->is_AddP() && n->in(Base) == in(Base)) {
574 const AddPNode *addp = n->as_AddP(); // Left input is an AddP
575 assert( !addp->in(Address)->is_AddP() ||
576 addp->in(Address)->as_AddP() != addp,
577 "dead loop in AddPNode::Ideal" );
578 // Type of left input's right input
579 const Type *t = phase->type( addp->in(Offset) );
580 if( t == Type::TOP ) return nullptr;
581 const TypeX *t12 = t->is_intptr_t();
582 if( t12->is_con() ) { // Left input is an add of a constant?
583 // If the right input is a constant, combine constants
584 const Type *temp_t2 = phase->type( in(Offset) );
585 if( temp_t2 == Type::TOP ) return nullptr;
586 const TypeX *t2 = temp_t2->is_intptr_t();
587 Node* address;
588 Node* offset;
589 if( t2->is_con() ) {
590 // The Add of the flattened expression
591 address = addp->in(Address);
592 offset = phase->MakeConX(t2->get_con() + t12->get_con());
593 } else {
594 // Else move the constant to the right. ((A+con)+B) into ((A+B)+con)
595 address = phase->transform(new AddPNode(in(Base),addp->in(Address),in(Offset)));
596 offset = addp->in(Offset);
597 }
598 set_req_X(Address, address, phase);
599 set_req_X(Offset, offset, phase);
600 return this;
601 }
602 }
603
604 // Raw pointers?
605 if( in(Base)->bottom_type() == Type::TOP ) {
606 // If this is a null+long form (from unsafe accesses), switch to a rawptr.
607 if (phase->type(in(Address)) == TypePtr::NULL_PTR) {
608 Node* offset = in(Offset);
609 return new CastX2PNode(offset);
610 }
611 }
612
613 // If the right is an add of a constant, push the offset down.
614 // Convert: (ptr + (offset+con)) into (ptr+offset)+con.
615 // The idea is to merge array_base+scaled_index groups together,
616 // and only have different constant offsets from the same base.
617 const Node *add = in(Offset);
618 if( add->Opcode() == Op_AddX && add->in(1) != add ) {
619 const Type *t22 = phase->type( add->in(2) );
620 if( t22->singleton() && (t22 != Type::TOP) ) { // Right input is an add of a constant?
621 set_req(Address, phase->transform(new AddPNode(in(Base),in(Address),add->in(1))));
622 set_req_X(Offset, add->in(2), phase); // puts add on igvn worklist if needed
623 return this; // Made progress
624 }
625 }
626
627 return nullptr; // No progress
628 }
629
630 //------------------------------bottom_type------------------------------------
631 // Bottom-type is the pointer-type with unknown offset.
632 const Type *AddPNode::bottom_type() const {
633 if (in(Address) == nullptr) return TypePtr::BOTTOM;
634 const TypePtr *tp = in(Address)->bottom_type()->isa_ptr();
635 if( !tp ) return Type::TOP; // TOP input means TOP output
636 assert( in(Offset)->Opcode() != Op_ConP, "" );
637 const Type *t = in(Offset)->bottom_type();
638 if( t == Type::TOP )
639 return tp->add_offset(Type::OffsetTop);
640 const TypeX *tx = t->is_intptr_t();
641 intptr_t txoffset = Type::OffsetBot;
642 if (tx->is_con()) { // Left input is an add of a constant?
643 txoffset = tx->get_con();
644 }
645 if (tp->isa_aryptr()) {
646 // In the case of a flat inline type array, each field has its
647 // own slice so we need to extract the field being accessed from
648 // the address computation
649 return tp->is_aryptr()->add_field_offset_and_offset(txoffset);
650 }
651 return tp->add_offset(txoffset);
652 }
653
654 //------------------------------Value------------------------------------------
655 const Type* AddPNode::Value(PhaseGVN* phase) const {
656 // Either input is TOP ==> the result is TOP
657 const Type *t1 = phase->type( in(Address) );
658 const Type *t2 = phase->type( in(Offset) );
659 if( t1 == Type::TOP ) return Type::TOP;
660 if( t2 == Type::TOP ) return Type::TOP;
661
662 // Left input is a pointer
663 const TypePtr *p1 = t1->isa_ptr();
664 // Right input is an int
665 const TypeX *p2 = t2->is_intptr_t();
666 // Add 'em
667 intptr_t p2offset = Type::OffsetBot;
668 if (p2->is_con()) { // Left input is an add of a constant?
669 p2offset = p2->get_con();
670 }
671 if (p1->isa_aryptr()) {
672 // In the case of a flat inline type array, each field has its
673 // own slice so we need to extract the field being accessed from
674 // the address computation
675 return p1->is_aryptr()->add_field_offset_and_offset(p2offset);
676 }
677 return p1->add_offset(p2offset);
678 }
679
680 //------------------------Ideal_base_and_offset--------------------------------
681 // Split an oop pointer into a base and offset.
682 // (The offset might be Type::OffsetBot in the case of an array.)
683 // Return the base, or null if failure.
684 Node* AddPNode::Ideal_base_and_offset(Node* ptr, PhaseValues* phase,
685 // second return value:
686 intptr_t& offset) {
687 if (ptr->is_AddP()) {
688 Node* base = ptr->in(AddPNode::Base);
689 Node* addr = ptr->in(AddPNode::Address);
690 Node* offs = ptr->in(AddPNode::Offset);
691 if (base == addr || base->is_top()) {
692 offset = phase->find_intptr_t_con(offs, Type::OffsetBot);
693 if (offset != Type::OffsetBot) {
694 return addr;
695 }
696 }
697 }
698 offset = Type::OffsetBot;
699 return nullptr;
700 }
701
702 //------------------------------unpack_offsets----------------------------------
703 // Collect the AddP offset values into the elements array, giving up
704 // if there are more than length.
705 int AddPNode::unpack_offsets(Node* elements[], int length) {
706 int count = 0;
707 Node* addr = this;
708 Node* base = addr->in(AddPNode::Base);
709 while (addr->is_AddP()) {
710 if (addr->in(AddPNode::Base) != base) {
711 // give up
712 return -1;
713 }
714 elements[count++] = addr->in(AddPNode::Offset);
715 if (count == length) {
716 // give up
717 return -1;
718 }
719 addr = addr->in(AddPNode::Address);
720 }
721 if (addr != base) {
722 return -1;
723 }
724 return count;
725 }
726
727 //------------------------------match_edge-------------------------------------
728 // Do we Match on this edge index or not? Do not match base pointer edge
729 uint AddPNode::match_edge(uint idx) const {
730 return idx > Base;
731 }
732
733 //=============================================================================
734 //------------------------------Identity---------------------------------------
735 Node* OrINode::Identity(PhaseGVN* phase) {
736 // x | x => x
737 if (in(1) == in(2)) {
738 return in(1);
739 }
740
741 return AddNode::Identity(phase);
742 }
743
744 // Find shift value for Integer or Long OR.
745 Node* rotate_shift(PhaseGVN* phase, Node* lshift, Node* rshift, int mask) {
746 // val << norm_con_shift | val >> ({32|64} - norm_con_shift) => rotate_left val, norm_con_shift
747 const TypeInt* lshift_t = phase->type(lshift)->isa_int();
748 const TypeInt* rshift_t = phase->type(rshift)->isa_int();
749 if (lshift_t != nullptr && lshift_t->is_con() &&
750 rshift_t != nullptr && rshift_t->is_con() &&
751 ((lshift_t->get_con() & mask) == ((mask + 1) - (rshift_t->get_con() & mask)))) {
752 return phase->intcon(lshift_t->get_con() & mask);
753 }
754 // val << var_shift | val >> ({0|32|64} - var_shift) => rotate_left val, var_shift
755 if (rshift->Opcode() == Op_SubI && rshift->in(2) == lshift && rshift->in(1)->is_Con()){
756 const TypeInt* shift_t = phase->type(rshift->in(1))->isa_int();
757 if (shift_t != nullptr && shift_t->is_con() &&
758 (shift_t->get_con() == 0 || shift_t->get_con() == (mask + 1))) {
759 return lshift;
760 }
761 }
762 return nullptr;
763 }
764
765 Node* OrINode::Ideal(PhaseGVN* phase, bool can_reshape) {
766 int lopcode = in(1)->Opcode();
767 int ropcode = in(2)->Opcode();
768 if (Matcher::match_rule_supported(Op_RotateLeft) &&
769 lopcode == Op_LShiftI && ropcode == Op_URShiftI && in(1)->in(1) == in(2)->in(1)) {
770 Node* lshift = in(1)->in(2);
771 Node* rshift = in(2)->in(2);
772 Node* shift = rotate_shift(phase, lshift, rshift, 0x1F);
773 if (shift != nullptr) {
774 return new RotateLeftNode(in(1)->in(1), shift, TypeInt::INT);
775 }
776 return nullptr;
777 }
778 if (Matcher::match_rule_supported(Op_RotateRight) &&
779 lopcode == Op_URShiftI && ropcode == Op_LShiftI && in(1)->in(1) == in(2)->in(1)) {
780 Node* rshift = in(1)->in(2);
781 Node* lshift = in(2)->in(2);
782 Node* shift = rotate_shift(phase, rshift, lshift, 0x1F);
783 if (shift != nullptr) {
784 return new RotateRightNode(in(1)->in(1), shift, TypeInt::INT);
785 }
786 }
787 return nullptr;
788 }
789
790 //------------------------------add_ring---------------------------------------
791 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
792 // the logical operations the ring's ADD is really a logical OR function.
793 // This also type-checks the inputs for sanity. Guaranteed never to
794 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
795 const Type *OrINode::add_ring( const Type *t0, const Type *t1 ) const {
796 const TypeInt *r0 = t0->is_int(); // Handy access
797 const TypeInt *r1 = t1->is_int();
798
799 // If both args are bool, can figure out better types
800 if ( r0 == TypeInt::BOOL ) {
801 if ( r1 == TypeInt::ONE) {
802 return TypeInt::ONE;
803 } else if ( r1 == TypeInt::BOOL ) {
804 return TypeInt::BOOL;
805 }
806 } else if ( r0 == TypeInt::ONE ) {
807 if ( r1 == TypeInt::BOOL ) {
808 return TypeInt::ONE;
809 }
810 }
811
812 // If either input is not a constant, just return all integers.
813 if( !r0->is_con() || !r1->is_con() )
814 return TypeInt::INT; // Any integer, but still no symbols.
815
816 // Otherwise just OR them bits.
817 return TypeInt::make( r0->get_con() | r1->get_con() );
818 }
819
820 //=============================================================================
821 //------------------------------Identity---------------------------------------
822 Node* OrLNode::Identity(PhaseGVN* phase) {
823 // x | x => x
824 if (in(1) == in(2)) {
825 return in(1);
826 }
827
828 return AddNode::Identity(phase);
829 }
830
831 Node* OrLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
832 int lopcode = in(1)->Opcode();
833 int ropcode = in(2)->Opcode();
834 if (Matcher::match_rule_supported(Op_RotateLeft) &&
835 lopcode == Op_LShiftL && ropcode == Op_URShiftL && in(1)->in(1) == in(2)->in(1)) {
836 Node* lshift = in(1)->in(2);
837 Node* rshift = in(2)->in(2);
838 Node* shift = rotate_shift(phase, lshift, rshift, 0x3F);
839 if (shift != nullptr) {
840 return new RotateLeftNode(in(1)->in(1), shift, TypeLong::LONG);
841 }
842 return nullptr;
843 }
844 if (Matcher::match_rule_supported(Op_RotateRight) &&
845 lopcode == Op_URShiftL && ropcode == Op_LShiftL && in(1)->in(1) == in(2)->in(1)) {
846 Node* rshift = in(1)->in(2);
847 Node* lshift = in(2)->in(2);
848 Node* shift = rotate_shift(phase, rshift, lshift, 0x3F);
849 if (shift != nullptr) {
850 return new RotateRightNode(in(1)->in(1), shift, TypeLong::LONG);
851 }
852 }
853 return nullptr;
854 }
855
856 //------------------------------add_ring---------------------------------------
857 const Type *OrLNode::add_ring( const Type *t0, const Type *t1 ) const {
858 const TypeLong *r0 = t0->is_long(); // Handy access
859 const TypeLong *r1 = t1->is_long();
860
861 // If either input is not a constant, just return all integers.
862 if( !r0->is_con() || !r1->is_con() )
863 return TypeLong::LONG; // Any integer, but still no symbols.
864
865 // Otherwise just OR them bits.
866 return TypeLong::make( r0->get_con() | r1->get_con() );
867 }
868
869 //---------------------------Helper -------------------------------------------
870 /* Decide if the given node is used only in arithmetic expressions(add or sub).
871 */
872 static bool is_used_in_only_arithmetic(Node* n, BasicType bt) {
873 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
874 Node* u = n->fast_out(i);
875 if (u->Opcode() != Op_Add(bt) && u->Opcode() != Op_Sub(bt)) {
876 return false;
877 }
878 }
879 return true;
880 }
881
882 //=============================================================================
883 //------------------------------Idealize---------------------------------------
884 Node* XorINode::Ideal(PhaseGVN* phase, bool can_reshape) {
885 Node* in1 = in(1);
886 Node* in2 = in(2);
887
888 // Convert ~x into -1-x when ~x is used in an arithmetic expression
889 // or x itself is an expression.
890 if (phase->type(in2) == TypeInt::MINUS_1) { // follows LHS^(-1), i.e., ~LHS
891 if (phase->is_IterGVN()) {
892 if (is_used_in_only_arithmetic(this, T_INT)
893 // LHS is arithmetic
894 || (in1->Opcode() == Op_AddI || in1->Opcode() == Op_SubI)) {
895 return new SubINode(in2, in1);
896 }
897 } else {
898 // graph could be incomplete in GVN so we postpone to IGVN
899 phase->record_for_igvn(this);
900 }
901 }
902
903 // Propagate xor through constant cmoves. This pattern can occur after expansion of Conv2B nodes.
904 const TypeInt* in2_type = phase->type(in2)->isa_int();
905 if (in1->Opcode() == Op_CMoveI && in2_type != nullptr && in2_type->is_con()) {
906 int in2_val = in2_type->get_con();
907
908 // Get types of both sides of the CMove
909 const TypeInt* left = phase->type(in1->in(CMoveNode::IfFalse))->isa_int();
910 const TypeInt* right = phase->type(in1->in(CMoveNode::IfTrue))->isa_int();
911
912 // Ensure that both sides are int constants
913 if (left != nullptr && right != nullptr && left->is_con() && right->is_con()) {
914 Node* cond = in1->in(CMoveNode::Condition);
915
916 // Check that the comparison is a bool and that the cmp node type is correct
917 if (cond->is_Bool()) {
918 int cmp_op = cond->in(1)->Opcode();
919
920 if (cmp_op == Op_CmpI || cmp_op == Op_CmpP) {
921 int l_val = left->get_con();
922 int r_val = right->get_con();
923
924 return new CMoveINode(cond, phase->intcon(l_val ^ in2_val), phase->intcon(r_val ^ in2_val), TypeInt::INT);
925 }
926 }
927 }
928 }
929
930 return AddNode::Ideal(phase, can_reshape);
931 }
932
933 const Type* XorINode::Value(PhaseGVN* phase) const {
934 Node* in1 = in(1);
935 Node* in2 = in(2);
936 const Type* t1 = phase->type(in1);
937 const Type* t2 = phase->type(in2);
938 if (t1 == Type::TOP || t2 == Type::TOP) {
939 return Type::TOP;
940 }
941 // x ^ x ==> 0
942 if (in1->eqv_uncast(in2)) {
943 return add_id();
944 }
945 // result of xor can only have bits sets where any of the
946 // inputs have bits set. lo can always become 0.
947 const TypeInt* t1i = t1->is_int();
948 const TypeInt* t2i = t2->is_int();
949 if ((t1i->_lo >= 0) &&
950 (t1i->_hi > 0) &&
951 (t2i->_lo >= 0) &&
952 (t2i->_hi > 0)) {
953 // hi - set all bits below the highest bit. Using round_down to avoid overflow.
954 const TypeInt* t1x = TypeInt::make(0, round_down_power_of_2(t1i->_hi) + (round_down_power_of_2(t1i->_hi) - 1), t1i->_widen);
955 const TypeInt* t2x = TypeInt::make(0, round_down_power_of_2(t2i->_hi) + (round_down_power_of_2(t2i->_hi) - 1), t2i->_widen);
956 return t1x->meet(t2x);
957 }
958 return AddNode::Value(phase);
959 }
960
961
962 //------------------------------add_ring---------------------------------------
963 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
964 // the logical operations the ring's ADD is really a logical OR function.
965 // This also type-checks the inputs for sanity. Guaranteed never to
966 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
967 const Type *XorINode::add_ring( const Type *t0, const Type *t1 ) const {
968 const TypeInt *r0 = t0->is_int(); // Handy access
969 const TypeInt *r1 = t1->is_int();
970
971 // Complementing a boolean?
972 if( r0 == TypeInt::BOOL && ( r1 == TypeInt::ONE
973 || r1 == TypeInt::BOOL))
974 return TypeInt::BOOL;
975
976 if( !r0->is_con() || !r1->is_con() ) // Not constants
977 return TypeInt::INT; // Any integer, but still no symbols.
978
979 // Otherwise just XOR them bits.
980 return TypeInt::make( r0->get_con() ^ r1->get_con() );
981 }
982
983 //=============================================================================
984 //------------------------------add_ring---------------------------------------
985 const Type *XorLNode::add_ring( const Type *t0, const Type *t1 ) const {
986 const TypeLong *r0 = t0->is_long(); // Handy access
987 const TypeLong *r1 = t1->is_long();
988
989 // If either input is not a constant, just return all integers.
990 if( !r0->is_con() || !r1->is_con() )
991 return TypeLong::LONG; // Any integer, but still no symbols.
992
993 // Otherwise just OR them bits.
994 return TypeLong::make( r0->get_con() ^ r1->get_con() );
995 }
996
997 Node* XorLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
998 Node* in1 = in(1);
999 Node* in2 = in(2);
1000
1001 // Convert ~x into -1-x when ~x is used in an arithmetic expression
1002 // or x itself is an arithmetic expression.
1003 if (phase->type(in2) == TypeLong::MINUS_1) { // follows LHS^(-1), i.e., ~LHS
1004 if (phase->is_IterGVN()) {
1005 if (is_used_in_only_arithmetic(this, T_LONG)
1006 // LHS is arithmetic
1007 || (in1->Opcode() == Op_AddL || in1->Opcode() == Op_SubL)) {
1008 return new SubLNode(in2, in1);
1009 }
1010 } else {
1011 // graph could be incomplete in GVN so we postpone to IGVN
1012 phase->record_for_igvn(this);
1013 }
1014 }
1015 return AddNode::Ideal(phase, can_reshape);
1016 }
1017
1018 const Type* XorLNode::Value(PhaseGVN* phase) const {
1019 Node* in1 = in(1);
1020 Node* in2 = in(2);
1021 const Type* t1 = phase->type(in1);
1022 const Type* t2 = phase->type(in2);
1023 if (t1 == Type::TOP || t2 == Type::TOP) {
1024 return Type::TOP;
1025 }
1026 // x ^ x ==> 0
1027 if (in1->eqv_uncast(in2)) {
1028 return add_id();
1029 }
1030 // result of xor can only have bits sets where any of the
1031 // inputs have bits set. lo can always become 0.
1032 const TypeLong* t1l = t1->is_long();
1033 const TypeLong* t2l = t2->is_long();
1034 if ((t1l->_lo >= 0) &&
1035 (t1l->_hi > 0) &&
1036 (t2l->_lo >= 0) &&
1037 (t2l->_hi > 0)) {
1038 // hi - set all bits below the highest bit. Using round_down to avoid overflow.
1039 const TypeLong* t1x = TypeLong::make(0, round_down_power_of_2(t1l->_hi) + (round_down_power_of_2(t1l->_hi) - 1), t1l->_widen);
1040 const TypeLong* t2x = TypeLong::make(0, round_down_power_of_2(t2l->_hi) + (round_down_power_of_2(t2l->_hi) - 1), t2l->_widen);
1041 return t1x->meet(t2x);
1042 }
1043 return AddNode::Value(phase);
1044 }
1045
1046 Node* build_min_max_int(Node* a, Node* b, bool is_max) {
1047 if (is_max) {
1048 return new MaxINode(a, b);
1049 } else {
1050 return new MinINode(a, b);
1051 }
1052 }
1053
1054 Node* MaxNode::build_min_max(Node* a, Node* b, bool is_max, bool is_unsigned, const Type* t, PhaseGVN& gvn) {
1055 bool is_int = gvn.type(a)->isa_int();
1056 assert(is_int || gvn.type(a)->isa_long(), "int or long inputs");
1057 assert(is_int == (gvn.type(b)->isa_int() != nullptr), "inconsistent inputs");
1058 BasicType bt = is_int ? T_INT: T_LONG;
1059 Node* hook = nullptr;
1060 if (gvn.is_IterGVN()) {
1061 // Make sure a and b are not destroyed
1062 hook = new Node(2);
1063 hook->init_req(0, a);
1064 hook->init_req(1, b);
1065 }
1066 Node* res = nullptr;
1067 if (is_int && !is_unsigned) {
1068 res = gvn.transform(build_min_max_int(a, b, is_max));
1069 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");
1070 } else {
1071 Node* cmp = nullptr;
1072 if (is_max) {
1073 cmp = gvn.transform(CmpNode::make(a, b, bt, is_unsigned));
1074 } else {
1075 cmp = gvn.transform(CmpNode::make(b, a, bt, is_unsigned));
1076 }
1077 Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::lt));
1078 res = gvn.transform(CMoveNode::make(nullptr, bol, a, b, t));
1079 }
1080 if (hook != nullptr) {
1081 hook->destruct(&gvn);
1082 }
1083 return res;
1084 }
1085
1086 Node* MaxNode::build_min_max_diff_with_zero(Node* a, Node* b, bool is_max, const Type* t, PhaseGVN& gvn) {
1087 bool is_int = gvn.type(a)->isa_int();
1088 assert(is_int || gvn.type(a)->isa_long(), "int or long inputs");
1089 assert(is_int == (gvn.type(b)->isa_int() != nullptr), "inconsistent inputs");
1090 BasicType bt = is_int ? T_INT: T_LONG;
1091 Node* zero = gvn.integercon(0, bt);
1092 Node* hook = nullptr;
1093 if (gvn.is_IterGVN()) {
1094 // Make sure a and b are not destroyed
1095 hook = new Node(2);
1096 hook->init_req(0, a);
1097 hook->init_req(1, b);
1098 }
1099 Node* cmp = nullptr;
1100 if (is_max) {
1101 cmp = gvn.transform(CmpNode::make(a, b, bt, false));
1102 } else {
1103 cmp = gvn.transform(CmpNode::make(b, a, bt, false));
1104 }
1105 Node* sub = gvn.transform(SubNode::make(a, b, bt));
1106 Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::lt));
1107 Node* res = gvn.transform(CMoveNode::make(nullptr, bol, sub, zero, t));
1108 if (hook != nullptr) {
1109 hook->destruct(&gvn);
1110 }
1111 return res;
1112 }
1113
1114 // Check if addition of an integer with type 't' and a constant 'c' can overflow.
1115 static bool can_overflow(const TypeInt* t, jint c) {
1116 jint t_lo = t->_lo;
1117 jint t_hi = t->_hi;
1118 return ((c < 0 && (java_add(t_lo, c) > t_lo)) ||
1119 (c > 0 && (java_add(t_hi, c) < t_hi)));
1120 }
1121
1122 // Let <x, x_off> = x_operands and <y, y_off> = y_operands.
1123 // If x == y and neither add(x, x_off) nor add(y, y_off) overflow, return
1124 // add(x, op(x_off, y_off)). Otherwise, return nullptr.
1125 Node* MaxNode::extract_add(PhaseGVN* phase, ConstAddOperands x_operands, ConstAddOperands y_operands) {
1126 Node* x = x_operands.first;
1127 Node* y = y_operands.first;
1128 int opcode = Opcode();
1129 assert(opcode == Op_MaxI || opcode == Op_MinI, "Unexpected opcode");
1130 const TypeInt* tx = phase->type(x)->isa_int();
1131 jint x_off = x_operands.second;
1132 jint y_off = y_operands.second;
1133 if (x == y && tx != nullptr &&
1134 !can_overflow(tx, x_off) &&
1135 !can_overflow(tx, y_off)) {
1136 jint c = opcode == Op_MinI ? MIN2(x_off, y_off) : MAX2(x_off, y_off);
1137 return new AddINode(x, phase->intcon(c));
1138 }
1139 return nullptr;
1140 }
1141
1142 // Try to cast n as an integer addition with a constant. Return:
1143 // <x, C>, if n == add(x, C), where 'C' is a non-TOP constant;
1144 // <nullptr, 0>, if n == add(x, C), where 'C' is a TOP constant; or
1145 // <n, 0>, otherwise.
1146 static ConstAddOperands as_add_with_constant(Node* n) {
1147 if (n->Opcode() != Op_AddI) {
1148 return ConstAddOperands(n, 0);
1149 }
1150 Node* x = n->in(1);
1151 Node* c = n->in(2);
1152 if (!c->is_Con()) {
1153 return ConstAddOperands(n, 0);
1154 }
1155 const Type* c_type = c->bottom_type();
1156 if (c_type == Type::TOP) {
1157 return ConstAddOperands(nullptr, 0);
1158 }
1159 return ConstAddOperands(x, c_type->is_int()->get_con());
1160 }
1161
1162 Node* MaxNode::IdealI(PhaseGVN* phase, bool can_reshape) {
1163 int opcode = Opcode();
1164 assert(opcode == Op_MinI || opcode == Op_MaxI, "Unexpected opcode");
1165 // Try to transform the following pattern, in any of its four possible
1166 // permutations induced by op's commutativity:
1167 // op(op(add(inner, inner_off), inner_other), add(outer, outer_off))
1168 // into
1169 // op(add(inner, op(inner_off, outer_off)), inner_other),
1170 // where:
1171 // op is either MinI or MaxI, and
1172 // inner == outer, and
1173 // the additions cannot overflow.
1174 for (uint inner_op_index = 1; inner_op_index <= 2; inner_op_index++) {
1175 if (in(inner_op_index)->Opcode() != opcode) {
1176 continue;
1177 }
1178 Node* outer_add = in(inner_op_index == 1 ? 2 : 1);
1179 ConstAddOperands outer_add_operands = as_add_with_constant(outer_add);
1180 if (outer_add_operands.first == nullptr) {
1181 return nullptr; // outer_add has a TOP input, no need to continue.
1182 }
1183 // One operand is a MinI/MaxI and the other is an integer addition with
1184 // constant. Test the operands of the inner MinI/MaxI.
1185 for (uint inner_add_index = 1; inner_add_index <= 2; inner_add_index++) {
1186 Node* inner_op = in(inner_op_index);
1187 Node* inner_add = inner_op->in(inner_add_index);
1188 ConstAddOperands inner_add_operands = as_add_with_constant(inner_add);
1189 if (inner_add_operands.first == nullptr) {
1190 return nullptr; // inner_add has a TOP input, no need to continue.
1191 }
1192 // Try to extract the inner add.
1193 Node* add_extracted = extract_add(phase, inner_add_operands, outer_add_operands);
1194 if (add_extracted == nullptr) {
1195 continue;
1196 }
1197 Node* add_transformed = phase->transform(add_extracted);
1198 Node* inner_other = inner_op->in(inner_add_index == 1 ? 2 : 1);
1199 return build_min_max_int(add_transformed, inner_other, opcode == Op_MaxI);
1200 }
1201 }
1202 // Try to transform
1203 // op(add(x, x_off), add(y, y_off))
1204 // into
1205 // add(x, op(x_off, y_off)),
1206 // where:
1207 // op is either MinI or MaxI, and
1208 // inner == outer, and
1209 // the additions cannot overflow.
1210 ConstAddOperands xC = as_add_with_constant(in(1));
1211 ConstAddOperands yC = as_add_with_constant(in(2));
1212 if (xC.first == nullptr || yC.first == nullptr) return nullptr;
1213 return extract_add(phase, xC, yC);
1214 }
1215
1216 // Ideal transformations for MaxINode
1217 Node* MaxINode::Ideal(PhaseGVN* phase, bool can_reshape) {
1218 return IdealI(phase, can_reshape);
1219 }
1220
1221 //=============================================================================
1222 //------------------------------add_ring---------------------------------------
1223 // Supplied function returns the sum of the inputs.
1224 const Type *MaxINode::add_ring( const Type *t0, const Type *t1 ) const {
1225 const TypeInt *r0 = t0->is_int(); // Handy access
1226 const TypeInt *r1 = t1->is_int();
1227
1228 // Otherwise just MAX them bits.
1229 return TypeInt::make( MAX2(r0->_lo,r1->_lo), MAX2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
1230 }
1231
1232 //=============================================================================
1233 //------------------------------Idealize---------------------------------------
1234 // MINs show up in range-check loop limit calculations. Look for
1235 // "MIN2(x+c0,MIN2(y,x+c1))". Pick the smaller constant: "MIN2(x+c0,y)"
1236 Node* MinINode::Ideal(PhaseGVN* phase, bool can_reshape) {
1237 return IdealI(phase, can_reshape);
1238 }
1239
1240 //------------------------------add_ring---------------------------------------
1241 // Supplied function returns the sum of the inputs.
1242 const Type *MinINode::add_ring( const Type *t0, const Type *t1 ) const {
1243 const TypeInt *r0 = t0->is_int(); // Handy access
1244 const TypeInt *r1 = t1->is_int();
1245
1246 // Otherwise just MIN them bits.
1247 return TypeInt::make( MIN2(r0->_lo,r1->_lo), MIN2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
1248 }
1249
1250 // Collapse the "addition with overflow-protection" pattern, and the symmetrical
1251 // "subtraction with underflow-protection" pattern. These are created during the
1252 // unrolling, when we have to adjust the limit by subtracting the stride, but want
1253 // to protect against underflow: MaxL(SubL(limit, stride), min_jint).
1254 // If we have more than one of those in a sequence:
1255 //
1256 // x con2
1257 // | |
1258 // AddL clamp2
1259 // | |
1260 // Max/MinL con1
1261 // | |
1262 // AddL clamp1
1263 // | |
1264 // Max/MinL (n)
1265 //
1266 // We want to collapse it to:
1267 //
1268 // x con1 con2
1269 // | | |
1270 // | AddLNode (new_con)
1271 // | |
1272 // AddLNode clamp1
1273 // | |
1274 // Max/MinL (n)
1275 //
1276 // Note: we assume that SubL was already replaced by an AddL, and that the stride
1277 // has its sign flipped: SubL(limit, stride) -> AddL(limit, -stride).
1278 Node* fold_subI_no_underflow_pattern(Node* n, PhaseGVN* phase) {
1279 assert(n->Opcode() == Op_MaxL || n->Opcode() == Op_MinL, "sanity");
1280 // Check that the two clamps have the correct values.
1281 jlong clamp = (n->Opcode() == Op_MaxL) ? min_jint : max_jint;
1282 auto is_clamp = [&](Node* c) {
1283 const TypeLong* t = phase->type(c)->isa_long();
1284 return t != nullptr && t->is_con() &&
1285 t->get_con() == clamp;
1286 };
1287 // Check that the constants are negative if MaxL, and positive if MinL.
1288 auto is_sub_con = [&](Node* c) {
1289 const TypeLong* t = phase->type(c)->isa_long();
1290 return t != nullptr && t->is_con() &&
1291 t->get_con() < max_jint && t->get_con() > min_jint &&
1292 (t->get_con() < 0) == (n->Opcode() == Op_MaxL);
1293 };
1294 // Verify the graph level by level:
1295 Node* add1 = n->in(1);
1296 Node* clamp1 = n->in(2);
1297 if (add1->Opcode() == Op_AddL && is_clamp(clamp1)) {
1298 Node* max2 = add1->in(1);
1299 Node* con1 = add1->in(2);
1300 if (max2->Opcode() == n->Opcode() && is_sub_con(con1)) {
1301 Node* add2 = max2->in(1);
1302 Node* clamp2 = max2->in(2);
1303 if (add2->Opcode() == Op_AddL && is_clamp(clamp2)) {
1304 Node* x = add2->in(1);
1305 Node* con2 = add2->in(2);
1306 if (is_sub_con(con2)) {
1307 Node* new_con = phase->transform(new AddLNode(con1, con2));
1308 Node* new_sub = phase->transform(new AddLNode(x, new_con));
1309 n->set_req_X(1, new_sub, phase);
1310 return n;
1311 }
1312 }
1313 }
1314 }
1315 return nullptr;
1316 }
1317
1318 const Type* MaxLNode::add_ring(const Type* t0, const Type* t1) const {
1319 const TypeLong* r0 = t0->is_long();
1320 const TypeLong* r1 = t1->is_long();
1321
1322 return TypeLong::make(MAX2(r0->_lo, r1->_lo), MAX2(r0->_hi, r1->_hi), MAX2(r0->_widen, r1->_widen));
1323 }
1324
1325 Node* MaxLNode::Identity(PhaseGVN* phase) {
1326 const TypeLong* t1 = phase->type(in(1))->is_long();
1327 const TypeLong* t2 = phase->type(in(2))->is_long();
1328
1329 // Can we determine maximum statically?
1330 if (t1->_lo >= t2->_hi) {
1331 return in(1);
1332 } else if (t2->_lo >= t1->_hi) {
1333 return in(2);
1334 }
1335
1336 return MaxNode::Identity(phase);
1337 }
1338
1339 Node* MaxLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1340 Node* n = AddNode::Ideal(phase, can_reshape);
1341 if (n != nullptr) {
1342 return n;
1343 }
1344 if (can_reshape) {
1345 return fold_subI_no_underflow_pattern(this, phase);
1346 }
1347 return nullptr;
1348 }
1349
1350 const Type* MinLNode::add_ring(const Type* t0, const Type* t1) const {
1351 const TypeLong* r0 = t0->is_long();
1352 const TypeLong* r1 = t1->is_long();
1353
1354 return TypeLong::make(MIN2(r0->_lo, r1->_lo), MIN2(r0->_hi, r1->_hi), MIN2(r0->_widen, r1->_widen));
1355 }
1356
1357 Node* MinLNode::Identity(PhaseGVN* phase) {
1358 const TypeLong* t1 = phase->type(in(1))->is_long();
1359 const TypeLong* t2 = phase->type(in(2))->is_long();
1360
1361 // Can we determine minimum statically?
1362 if (t1->_lo >= t2->_hi) {
1363 return in(2);
1364 } else if (t2->_lo >= t1->_hi) {
1365 return in(1);
1366 }
1367
1368 return MaxNode::Identity(phase);
1369 }
1370
1371 Node* MinLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1372 Node* n = AddNode::Ideal(phase, can_reshape);
1373 if (n != nullptr) {
1374 return n;
1375 }
1376 if (can_reshape) {
1377 return fold_subI_no_underflow_pattern(this, phase);
1378 }
1379 return nullptr;
1380 }
1381
1382 //------------------------------add_ring---------------------------------------
1383 const Type* MinFNode::add_ring(const Type* t0, const Type* t1 ) const {
1384 const TypeF* r0 = t0->isa_float_constant();
1385 const TypeF* r1 = t1->isa_float_constant();
1386 if (r0 == nullptr || r1 == nullptr) {
1387 return bottom_type();
1388 }
1389
1390 if (r0->is_nan()) {
1391 return r0;
1392 }
1393 if (r1->is_nan()) {
1394 return r1;
1395 }
1396
1397 float f0 = r0->getf();
1398 float f1 = r1->getf();
1399 if (f0 != 0.0f || f1 != 0.0f) {
1400 return f0 < f1 ? r0 : r1;
1401 }
1402
1403 // handle min of 0.0, -0.0 case.
1404 return (jint_cast(f0) < jint_cast(f1)) ? r0 : r1;
1405 }
1406
1407 //------------------------------add_ring---------------------------------------
1408 const Type* MinDNode::add_ring(const Type* t0, const Type* t1) const {
1409 const TypeD* r0 = t0->isa_double_constant();
1410 const TypeD* r1 = t1->isa_double_constant();
1411 if (r0 == nullptr || r1 == nullptr) {
1412 return bottom_type();
1413 }
1414
1415 if (r0->is_nan()) {
1416 return r0;
1417 }
1418 if (r1->is_nan()) {
1419 return r1;
1420 }
1421
1422 double d0 = r0->getd();
1423 double d1 = r1->getd();
1424 if (d0 != 0.0 || d1 != 0.0) {
1425 return d0 < d1 ? r0 : r1;
1426 }
1427
1428 // handle min of 0.0, -0.0 case.
1429 return (jlong_cast(d0) < jlong_cast(d1)) ? r0 : r1;
1430 }
1431
1432 //------------------------------add_ring---------------------------------------
1433 const Type* MaxFNode::add_ring(const Type* t0, const Type* t1) const {
1434 const TypeF* r0 = t0->isa_float_constant();
1435 const TypeF* r1 = t1->isa_float_constant();
1436 if (r0 == nullptr || r1 == nullptr) {
1437 return bottom_type();
1438 }
1439
1440 if (r0->is_nan()) {
1441 return r0;
1442 }
1443 if (r1->is_nan()) {
1444 return r1;
1445 }
1446
1447 float f0 = r0->getf();
1448 float f1 = r1->getf();
1449 if (f0 != 0.0f || f1 != 0.0f) {
1450 return f0 > f1 ? r0 : r1;
1451 }
1452
1453 // handle max of 0.0,-0.0 case.
1454 return (jint_cast(f0) > jint_cast(f1)) ? r0 : r1;
1455 }
1456
1457 //------------------------------add_ring---------------------------------------
1458 const Type* MaxDNode::add_ring(const Type* t0, const Type* t1) const {
1459 const TypeD* r0 = t0->isa_double_constant();
1460 const TypeD* r1 = t1->isa_double_constant();
1461 if (r0 == nullptr || r1 == nullptr) {
1462 return bottom_type();
1463 }
1464
1465 if (r0->is_nan()) {
1466 return r0;
1467 }
1468 if (r1->is_nan()) {
1469 return r1;
1470 }
1471
1472 double d0 = r0->getd();
1473 double d1 = r1->getd();
1474 if (d0 != 0.0 || d1 != 0.0) {
1475 return d0 > d1 ? r0 : r1;
1476 }
1477
1478 // handle max of 0.0, -0.0 case.
1479 return (jlong_cast(d0) > jlong_cast(d1)) ? r0 : r1;
1480 }