1 /*
2 * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "ci/ciObjArrayKlass.hpp"
26 #include "compiler/compileLog.hpp"
27 #include "gc/shared/barrierSet.hpp"
28 #include "gc/shared/c2/barrierSetC2.hpp"
29 #include "memory/allocation.inline.hpp"
30 #include "opto/addnode.hpp"
31 #include "opto/callnode.hpp"
32 #include "opto/castnode.hpp"
33 #include "opto/cfgnode.hpp"
34 #include "opto/convertnode.hpp"
35 #include "opto/inlinetypenode.hpp"
36 #include "opto/loopnode.hpp"
37 #include "opto/matcher.hpp"
38 #include "opto/movenode.hpp"
39 #include "opto/mulnode.hpp"
40 #include "opto/opaquenode.hpp"
41 #include "opto/opcodes.hpp"
42 #include "opto/phaseX.hpp"
43 #include "opto/subnode.hpp"
44 #include "runtime/arguments.hpp"
45 #include "runtime/sharedRuntime.hpp"
46 #include "utilities/reverse_bits.hpp"
47
48 // Portions of code courtesy of Clifford Click
49
50 // Optimization - Graph Style
51
52 #include "math.h"
53
54 //=============================================================================
55 //------------------------------Identity---------------------------------------
56 // If right input is a constant 0, return the left input.
57 Node* SubNode::Identity(PhaseGVN* phase) {
58 assert(in(1) != this, "Must already have called Value");
59 assert(in(2) != this, "Must already have called Value");
60
61 const Type* zero = add_id();
62
63 // Remove double negation if it is not a floating point number since negation
64 // is not the same as subtraction for floating point numbers
65 // (cf. JLS § 15.15.4). `0-(0-(-0.0))` must be equal to positive 0.0 according to
66 // JLS § 15.8.2, but would result in -0.0 if this folding would be applied.
67 if (phase->type(in(1))->higher_equal(zero) &&
68 in(2)->Opcode() == Opcode() &&
69 phase->type(in(2)->in(1))->higher_equal(zero) &&
70 !phase->type(in(2)->in(2))->is_floatingpoint()) {
71 return in(2)->in(2);
72 }
73
74 // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y
75 if (in(1)->Opcode() == Op_AddI || in(1)->Opcode() == Op_AddL) {
76 if (in(1)->in(2) == in(2)) {
77 return in(1)->in(1);
78 }
79 if (in(1)->in(1) == in(2)) {
80 return in(1)->in(2);
81 }
82 }
83
84 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this;
85 }
86
87 //------------------------------Value------------------------------------------
88 // A subtract node differences it's two inputs.
89 const Type* SubNode::Value_common(PhaseValues* phase) const {
90 const Node* in1 = in(1);
91 const Node* in2 = in(2);
92 // Either input is TOP ==> the result is TOP
93 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
94 if( t1 == Type::TOP ) return Type::TOP;
95 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
96 if( t2 == Type::TOP ) return Type::TOP;
97
98 // Not correct for SubFnode and AddFNode (must check for infinity)
99 // Equal? Subtract is zero
100 if (in1->eqv_uncast(in2)) return add_id();
101
102 // Either input is BOTTOM ==> the result is the local BOTTOM
103 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM )
104 return bottom_type();
105
106 return nullptr;
107 }
108
109 const Type* SubNode::Value(PhaseGVN* phase) const {
110 const Type* t = Value_common(phase);
111 if (t != nullptr) {
112 return t;
113 }
114 const Type* t1 = phase->type(in(1));
115 const Type* t2 = phase->type(in(2));
116 return sub(t1,t2); // Local flavor of type subtraction
117
118 }
119
120 SubNode* SubNode::make(Node* in1, Node* in2, BasicType bt) {
121 switch (bt) {
122 case T_INT:
123 return new SubINode(in1, in2);
124 case T_LONG:
125 return new SubLNode(in1, in2);
126 default:
127 fatal("Not implemented for %s", type2name(bt));
128 }
129 return nullptr;
130 }
131
132 //=============================================================================
133 //------------------------------Helper function--------------------------------
134
135 static bool is_cloop_increment(Node* inc) {
136 precond(inc->Opcode() == Op_AddI || inc->Opcode() == Op_AddL);
137
138 if (!inc->in(1)->is_Phi()) {
139 return false;
140 }
141 const PhiNode* phi = inc->in(1)->as_Phi();
142
143 if (!phi->region()->is_CountedLoop()) {
144 return false;
145 }
146
147 return inc == phi->region()->as_CountedLoop()->incr();
148 }
149
150 // Given the expression '(x + C) - v', or
151 // 'v - (x + C)', we examine nodes '+' and 'v':
152 //
153 // 1. Do not convert if '+' is a counted-loop increment, because the '-' is
154 // loop invariant and converting extends the live-range of 'x' to overlap
155 // with the '+', forcing another register to be used in the loop.
156 //
157 // 2. Do not convert if 'v' is a counted-loop induction variable, because
158 // 'x' might be invariant.
159 //
160 static bool ok_to_convert(Node* inc, Node* var) {
161 return !(is_cloop_increment(inc) || var->is_cloop_ind_var());
162 }
163
164 static bool is_cloop_condition(BoolNode* bol) {
165 for (DUIterator_Fast imax, i = bol->fast_outs(imax); i < imax; i++) {
166 Node* out = bol->fast_out(i);
167 if (out->is_BaseCountedLoopEnd()) {
168 return true;
169 }
170 }
171 return false;
172 }
173
174 //------------------------------Ideal------------------------------------------
175 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){
176 Node *in1 = in(1);
177 Node *in2 = in(2);
178 uint op1 = in1->Opcode();
179 uint op2 = in2->Opcode();
180
181 #ifdef ASSERT
182 // Check for dead loop
183 if ((in1 == this) || (in2 == this) ||
184 ((op1 == Op_AddI || op1 == Op_SubI) &&
185 ((in1->in(1) == this) || (in1->in(2) == this) ||
186 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
187 assert(false, "dead loop in SubINode::Ideal");
188 }
189 #endif
190
191 const Type *t2 = phase->type( in2 );
192 if( t2 == Type::TOP ) return nullptr;
193 // Convert "x-c0" into "x+ -c0".
194 if( t2->base() == Type::Int ){ // Might be bottom or top...
195 const TypeInt *i = t2->is_int();
196 if( i->is_con() )
197 return new AddINode(in1, phase->intcon(java_negate(i->get_con())));
198 }
199
200 // Convert "(x+c0) - y" into (x-y) + c0"
201 // Do not collapse (x+c0)-y if "+" is a loop increment or
202 // if "y" is a loop induction variable.
203 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) {
204 const Type *tadd = phase->type( in1->in(2) );
205 if( tadd->singleton() && tadd != Type::TOP ) {
206 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 ));
207 return new AddINode( sub2, in1->in(2) );
208 }
209 }
210
211 // Convert "x - (y+c0)" into "(x-y) - c0" AND
212 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
213 // Need the same check as in above optimization but reversed.
214 if (op2 == Op_AddI
215 && ok_to_convert(in2, in1)
216 && in2->in(2)->Opcode() == Op_ConI) {
217 jint c0 = phase->type(in2->in(2))->isa_int()->get_con();
218 Node* in21 = in2->in(1);
219 if (in1->Opcode() == Op_ConI) {
220 // Match c1
221 jint c1 = phase->type(in1)->isa_int()->get_con();
222 Node* sub2 = phase->intcon(java_subtract(c1, c0));
223 return new SubINode(sub2, in21);
224 } else {
225 // Match x
226 Node* sub2 = phase->transform(new SubINode(in1, in21));
227 Node* neg_c0 = phase->intcon(java_negate(c0));
228 return new AddINode(sub2, neg_c0);
229 }
230 }
231
232 const Type *t1 = phase->type( in1 );
233 if( t1 == Type::TOP ) return nullptr;
234
235 #ifdef ASSERT
236 // Check for dead loop
237 if ((op2 == Op_AddI || op2 == Op_SubI) &&
238 ((in2->in(1) == this) || (in2->in(2) == this) ||
239 (in2->in(1) == in2) || (in2->in(2) == in2))) {
240 assert(false, "dead loop in SubINode::Ideal");
241 }
242 #endif
243
244 // Convert "x - (x+y)" into "-y"
245 if (op2 == Op_AddI && in1 == in2->in(1)) {
246 return new SubINode(phase->intcon(0), in2->in(2));
247 }
248 // Convert "(x-y) - x" into "-y"
249 if (op1 == Op_SubI && in1->in(1) == in2) {
250 return new SubINode(phase->intcon(0), in1->in(2));
251 }
252 // Convert "x - (y+x)" into "-y"
253 if (op2 == Op_AddI && in1 == in2->in(2)) {
254 return new SubINode(phase->intcon(0), in2->in(1));
255 }
256
257 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity().
258 if (t1 == TypeInt::ZERO && op2 == Op_SubI && phase->type(in2->in(1)) != TypeInt::ZERO) {
259 return new SubINode(in2->in(2), in2->in(1));
260 }
261
262 // Convert "0 - (x+con)" into "-con-x"
263 jint con;
264 if( t1 == TypeInt::ZERO && op2 == Op_AddI &&
265 (con = in2->in(2)->find_int_con(0)) != 0 )
266 return new SubINode( phase->intcon(-con), in2->in(1) );
267
268 // Convert "(X+A) - (X+B)" into "A - B"
269 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) )
270 return new SubINode( in1->in(2), in2->in(2) );
271
272 // Convert "(A+X) - (B+X)" into "A - B"
273 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) )
274 return new SubINode( in1->in(1), in2->in(1) );
275
276 // Convert "(A+X) - (X+B)" into "A - B"
277 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) )
278 return new SubINode( in1->in(1), in2->in(2) );
279
280 // Convert "(X+A) - (B+X)" into "A - B"
281 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) )
282 return new SubINode( in1->in(2), in2->in(1) );
283
284 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally
285 // nicer to optimize than subtract.
286 if( op2 == Op_SubI && in2->outcnt() == 1) {
287 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) );
288 return new SubINode( add1, in2->in(1) );
289 }
290
291 // Associative
292 if (op1 == Op_MulI && op2 == Op_MulI) {
293 Node* sub_in1 = nullptr;
294 Node* sub_in2 = nullptr;
295 Node* mul_in = nullptr;
296
297 if (in1->in(1) == in2->in(1)) {
298 // Convert "a*b-a*c into a*(b-c)
299 sub_in1 = in1->in(2);
300 sub_in2 = in2->in(2);
301 mul_in = in1->in(1);
302 } else if (in1->in(2) == in2->in(1)) {
303 // Convert a*b-b*c into b*(a-c)
304 sub_in1 = in1->in(1);
305 sub_in2 = in2->in(2);
306 mul_in = in1->in(2);
307 } else if (in1->in(2) == in2->in(2)) {
308 // Convert a*c-b*c into (a-b)*c
309 sub_in1 = in1->in(1);
310 sub_in2 = in2->in(1);
311 mul_in = in1->in(2);
312 } else if (in1->in(1) == in2->in(2)) {
313 // Convert a*b-c*a into a*(b-c)
314 sub_in1 = in1->in(2);
315 sub_in2 = in2->in(1);
316 mul_in = in1->in(1);
317 }
318
319 if (mul_in != nullptr) {
320 Node* sub = phase->transform(new SubINode(sub_in1, sub_in2));
321 return new MulINode(mul_in, sub);
322 }
323 }
324
325 // Convert "0-(A>>31)" into "(A>>>31)"
326 if ( op2 == Op_RShiftI ) {
327 Node *in21 = in2->in(1);
328 Node *in22 = in2->in(2);
329 const TypeInt *zero = phase->type(in1)->isa_int();
330 const TypeInt *t21 = phase->type(in21)->isa_int();
331 const TypeInt *t22 = phase->type(in22)->isa_int();
332 if ( t21 && t22 && zero == TypeInt::ZERO && t22->is_con(31) ) {
333 return new URShiftINode(in21, in22);
334 }
335 }
336
337 return nullptr;
338 }
339
340 //------------------------------sub--------------------------------------------
341 // A subtract node differences it's two inputs.
342 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const {
343 const TypeInt *r0 = t1->is_int(); // Handy access
344 const TypeInt *r1 = t2->is_int();
345 int32_t lo = java_subtract(r0->_lo, r1->_hi);
346 int32_t hi = java_subtract(r0->_hi, r1->_lo);
347
348 // We next check for 32-bit overflow.
349 // If that happens, we just assume all integers are possible.
350 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
351 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
352 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
353 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
354 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen));
355 else // Overflow; assume all integers
356 return TypeInt::INT;
357 }
358
359 //=============================================================================
360 //------------------------------Ideal------------------------------------------
361 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
362 Node *in1 = in(1);
363 Node *in2 = in(2);
364 uint op1 = in1->Opcode();
365 uint op2 = in2->Opcode();
366
367 #ifdef ASSERT
368 // Check for dead loop
369 if ((in1 == this) || (in2 == this) ||
370 ((op1 == Op_AddL || op1 == Op_SubL) &&
371 ((in1->in(1) == this) || (in1->in(2) == this) ||
372 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
373 assert(false, "dead loop in SubLNode::Ideal");
374 }
375 #endif
376
377 if( phase->type( in2 ) == Type::TOP ) return nullptr;
378 const TypeLong *i = phase->type( in2 )->isa_long();
379 // Convert "x-c0" into "x+ -c0".
380 if( i && // Might be bottom or top...
381 i->is_con() )
382 return new AddLNode(in1, phase->longcon(java_negate(i->get_con())));
383
384 // Convert "(x+c0) - y" into (x-y) + c0"
385 // Do not collapse (x+c0)-y if "+" is a loop increment or
386 // if "y" is a loop induction variable.
387 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) {
388 Node *in11 = in1->in(1);
389 const Type *tadd = phase->type( in1->in(2) );
390 if( tadd->singleton() && tadd != Type::TOP ) {
391 Node *sub2 = phase->transform( new SubLNode( in11, in2 ));
392 return new AddLNode( sub2, in1->in(2) );
393 }
394 }
395
396 // Convert "x - (y+c0)" into "(x-y) - c0" AND
397 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
398 // Need the same check as in above optimization but reversed.
399 if (op2 == Op_AddL
400 && ok_to_convert(in2, in1)
401 && in2->in(2)->Opcode() == Op_ConL) {
402 jlong c0 = phase->type(in2->in(2))->isa_long()->get_con();
403 Node* in21 = in2->in(1);
404 if (in1->Opcode() == Op_ConL) {
405 // Match c1
406 jlong c1 = phase->type(in1)->isa_long()->get_con();
407 Node* sub2 = phase->longcon(java_subtract(c1, c0));
408 return new SubLNode(sub2, in21);
409 } else {
410 Node* sub2 = phase->transform(new SubLNode(in1, in21));
411 Node* neg_c0 = phase->longcon(java_negate(c0));
412 return new AddLNode(sub2, neg_c0);
413 }
414 }
415
416 const Type *t1 = phase->type( in1 );
417 if( t1 == Type::TOP ) return nullptr;
418
419 #ifdef ASSERT
420 // Check for dead loop
421 if ((op2 == Op_AddL || op2 == Op_SubL) &&
422 ((in2->in(1) == this) || (in2->in(2) == this) ||
423 (in2->in(1) == in2) || (in2->in(2) == in2))) {
424 assert(false, "dead loop in SubLNode::Ideal");
425 }
426 #endif
427
428 // Convert "x - (x+y)" into "-y"
429 if (op2 == Op_AddL && in1 == in2->in(1)) {
430 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(2));
431 }
432 // Convert "(x-y) - x" into "-y"
433 if (op1 == Op_SubL && in1->in(1) == in2) {
434 return new SubLNode(phase->makecon(TypeLong::ZERO), in1->in(2));
435 }
436 // Convert "x - (y+x)" into "-y"
437 if (op2 == Op_AddL && in1 == in2->in(2)) {
438 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(1));
439 }
440
441 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity.
442 if (t1 == TypeLong::ZERO && op2 == Op_SubL && phase->type(in2->in(1)) != TypeLong::ZERO) {
443 return new SubLNode(in2->in(2), in2->in(1));
444 }
445
446 // Convert "(X+A) - (X+B)" into "A - B"
447 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) )
448 return new SubLNode( in1->in(2), in2->in(2) );
449
450 // Convert "(A+X) - (B+X)" into "A - B"
451 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) )
452 return new SubLNode( in1->in(1), in2->in(1) );
453
454 // Convert "(A+X) - (X+B)" into "A - B"
455 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(1) )
456 return new SubLNode( in1->in(1), in2->in(2) );
457
458 // Convert "(X+A) - (B+X)" into "A - B"
459 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(2) )
460 return new SubLNode( in1->in(2), in2->in(1) );
461
462 // Convert "A-(B-C)" into (A+C)-B"
463 if( op2 == Op_SubL && in2->outcnt() == 1) {
464 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) );
465 return new SubLNode( add1, in2->in(1) );
466 }
467
468 // Associative
469 if (op1 == Op_MulL && op2 == Op_MulL) {
470 Node* sub_in1 = nullptr;
471 Node* sub_in2 = nullptr;
472 Node* mul_in = nullptr;
473
474 if (in1->in(1) == in2->in(1)) {
475 // Convert "a*b-a*c into a*(b+c)
476 sub_in1 = in1->in(2);
477 sub_in2 = in2->in(2);
478 mul_in = in1->in(1);
479 } else if (in1->in(2) == in2->in(1)) {
480 // Convert a*b-b*c into b*(a-c)
481 sub_in1 = in1->in(1);
482 sub_in2 = in2->in(2);
483 mul_in = in1->in(2);
484 } else if (in1->in(2) == in2->in(2)) {
485 // Convert a*c-b*c into (a-b)*c
486 sub_in1 = in1->in(1);
487 sub_in2 = in2->in(1);
488 mul_in = in1->in(2);
489 } else if (in1->in(1) == in2->in(2)) {
490 // Convert a*b-c*a into a*(b-c)
491 sub_in1 = in1->in(2);
492 sub_in2 = in2->in(1);
493 mul_in = in1->in(1);
494 }
495
496 if (mul_in != nullptr) {
497 Node* sub = phase->transform(new SubLNode(sub_in1, sub_in2));
498 return new MulLNode(mul_in, sub);
499 }
500 }
501
502 // Convert "0L-(A>>63)" into "(A>>>63)"
503 if ( op2 == Op_RShiftL ) {
504 Node *in21 = in2->in(1);
505 Node *in22 = in2->in(2);
506 const TypeLong *zero = phase->type(in1)->isa_long();
507 const TypeLong *t21 = phase->type(in21)->isa_long();
508 const TypeInt *t22 = phase->type(in22)->isa_int();
509 if ( t21 && t22 && zero == TypeLong::ZERO && t22->is_con(63) ) {
510 return new URShiftLNode(in21, in22);
511 }
512 }
513
514 return nullptr;
515 }
516
517 //------------------------------sub--------------------------------------------
518 // A subtract node differences it's two inputs.
519 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const {
520 const TypeLong *r0 = t1->is_long(); // Handy access
521 const TypeLong *r1 = t2->is_long();
522 jlong lo = java_subtract(r0->_lo, r1->_hi);
523 jlong hi = java_subtract(r0->_hi, r1->_lo);
524
525 // We next check for 32-bit overflow.
526 // If that happens, we just assume all integers are possible.
527 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
528 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
529 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
530 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
531 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen));
532 else // Overflow; assume all integers
533 return TypeLong::LONG;
534 }
535
536 //=============================================================================
537 //------------------------------Value------------------------------------------
538 // A subtract node differences its two inputs.
539 const Type* SubFPNode::Value(PhaseGVN* phase) const {
540 const Node* in1 = in(1);
541 const Node* in2 = in(2);
542 // Either input is TOP ==> the result is TOP
543 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
544 if( t1 == Type::TOP ) return Type::TOP;
545 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
546 if( t2 == Type::TOP ) return Type::TOP;
547
548 // if both operands are infinity of same sign, the result is NaN; do
549 // not replace with zero
550 if (t1->is_finite() && t2->is_finite() && in1 == in2) {
551 return add_id();
552 }
553
554 // Either input is BOTTOM ==> the result is the local BOTTOM
555 const Type *bot = bottom_type();
556 if( (t1 == bot) || (t2 == bot) ||
557 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
558 return bot;
559
560 return sub(t1,t2); // Local flavor of type subtraction
561 }
562
563
564 //=============================================================================
565 //------------------------------sub--------------------------------------------
566 // A subtract node differences its two inputs.
567 const Type* SubHFNode::sub(const Type* t1, const Type* t2) const {
568 // Half precision floating point subtraction follows the rules of IEEE 754
569 // applicable to other floating point types.
570 if (t1->isa_half_float_constant() != nullptr &&
571 t2->isa_half_float_constant() != nullptr) {
572 return TypeH::make(t1->getf() - t2->getf());
573 } else {
574 return Type::HALF_FLOAT;
575 }
576 }
577
578 //------------------------------Ideal------------------------------------------
579 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
580 const Type *t2 = phase->type( in(2) );
581 // Convert "x-c0" into "x+ -c0".
582 if( t2->base() == Type::FloatCon ) { // Might be bottom or top...
583 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) );
584 }
585
586 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes
587 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0.
588 //if( phase->type(in(1)) == TypeF::ZERO )
589 //return new (phase->C, 2) NegFNode(in(2));
590
591 return nullptr;
592 }
593
594 //------------------------------sub--------------------------------------------
595 // A subtract node differences its two inputs.
596 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const {
597 // no folding if one of operands is infinity or NaN, do not do constant folding
598 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) {
599 return TypeF::make( t1->getf() - t2->getf() );
600 }
601 else if( g_isnan(t1->getf()) ) {
602 return t1;
603 }
604 else if( g_isnan(t2->getf()) ) {
605 return t2;
606 }
607 else {
608 return Type::FLOAT;
609 }
610 }
611
612 //=============================================================================
613 //------------------------------Ideal------------------------------------------
614 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){
615 const Type *t2 = phase->type( in(2) );
616 // Convert "x-c0" into "x+ -c0".
617 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top...
618 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) );
619 }
620
621 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes
622 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0.
623 //if( phase->type(in(1)) == TypeD::ZERO )
624 //return new (phase->C, 2) NegDNode(in(2));
625
626 return nullptr;
627 }
628
629 //------------------------------sub--------------------------------------------
630 // A subtract node differences its two inputs.
631 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const {
632 // no folding if one of operands is infinity or NaN, do not do constant folding
633 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) {
634 return TypeD::make( t1->getd() - t2->getd() );
635 }
636 else if( g_isnan(t1->getd()) ) {
637 return t1;
638 }
639 else if( g_isnan(t2->getd()) ) {
640 return t2;
641 }
642 else {
643 return Type::DOUBLE;
644 }
645 }
646
647 //=============================================================================
648 //------------------------------Idealize---------------------------------------
649 // Unlike SubNodes, compare must still flatten return value to the
650 // range -1, 0, 1.
651 // And optimizations like those for (X + Y) - X fail if overflow happens.
652 Node* CmpNode::Identity(PhaseGVN* phase) {
653 return this;
654 }
655
656 CmpNode *CmpNode::make(Node *in1, Node *in2, BasicType bt, bool unsigned_comp) {
657 switch (bt) {
658 case T_INT:
659 if (unsigned_comp) {
660 return new CmpUNode(in1, in2);
661 }
662 return new CmpINode(in1, in2);
663 case T_LONG:
664 if (unsigned_comp) {
665 return new CmpULNode(in1, in2);
666 }
667 return new CmpLNode(in1, in2);
668 case T_OBJECT:
669 case T_ARRAY:
670 case T_ADDRESS:
671 case T_METADATA:
672 return new CmpPNode(in1, in2);
673 case T_NARROWOOP:
674 case T_NARROWKLASS:
675 return new CmpNNode(in1, in2);
676 default:
677 fatal("Not implemented for %s", type2name(bt));
678 }
679 return nullptr;
680 }
681
682 //=============================================================================
683 //------------------------------cmp--------------------------------------------
684 // Simplify a CmpI (compare 2 integers) node, based on local information.
685 // If both inputs are constants, compare them.
686 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const {
687 const TypeInt *r0 = t1->is_int(); // Handy access
688 const TypeInt *r1 = t2->is_int();
689
690 if( r0->_hi < r1->_lo ) // Range is always low?
691 return TypeInt::CC_LT;
692 else if( r0->_lo > r1->_hi ) // Range is always high?
693 return TypeInt::CC_GT;
694
695 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
696 assert(r0->get_con() == r1->get_con(), "must be equal");
697 return TypeInt::CC_EQ; // Equal results.
698 } else if( r0->_hi == r1->_lo ) // Range is never high?
699 return TypeInt::CC_LE;
700 else if( r0->_lo == r1->_hi ) // Range is never low?
701 return TypeInt::CC_GE;
702
703 const Type* joined = r0->join(r1);
704 if (joined == Type::TOP) {
705 return TypeInt::CC_NE;
706 }
707 return TypeInt::CC; // else use worst case results
708 }
709
710 const Type* CmpINode::Value(PhaseGVN* phase) const {
711 Node* in1 = in(1);
712 Node* in2 = in(2);
713 // If this test is the zero trip guard for a main or post loop, check whether, with the opaque node removed, the test
714 // would constant fold so the loop is never entered. If so return the type of the test without the opaque node removed:
715 // make the loop unreachable.
716 // The reason for this is that the iv phi captures the bounds of the loop and if the loop becomes unreachable, it can
717 // become top. In that case, the loop must be removed.
718 // This is safe because:
719 // - as optimizations proceed, the range of iterations executed by the main loop narrows. If no iterations remain, then
720 // we're done with optimizations for that loop.
721 // - the post loop is initially not reachable but as long as there's a main loop, the zero trip guard for the post
722 // loop takes a phi that merges the pre and main loop's iv and can't constant fold the zero trip guard. Once, the main
723 // loop is removed, there's no need to preserve the zero trip guard for the post loop anymore.
724 if (in1 != nullptr && in2 != nullptr) {
725 uint input = 0;
726 Node* cmp = nullptr;
727 BoolTest::mask test;
728 if (in1->Opcode() == Op_OpaqueZeroTripGuard && phase->type(in1) != Type::TOP) {
729 cmp = new CmpINode(in1->in(1), in2);
730 test = ((OpaqueZeroTripGuardNode*)in1)->_loop_entered_mask;
731 }
732 if (in2->Opcode() == Op_OpaqueZeroTripGuard && phase->type(in2) != Type::TOP) {
733 assert(cmp == nullptr, "A cmp with 2 OpaqueZeroTripGuard inputs");
734 cmp = new CmpINode(in1, in2->in(1));
735 test = ((OpaqueZeroTripGuardNode*)in2)->_loop_entered_mask;
736 }
737 if (cmp != nullptr) {
738 const Type* cmp_t = cmp->Value(phase);
739 const Type* t = BoolTest(test).cc2logical(cmp_t);
740 cmp->destruct(phase);
741 if (t == TypeInt::ZERO) {
742 return cmp_t;
743 }
744 }
745 }
746
747 return SubNode::Value(phase);
748 }
749
750
751 // Simplify a CmpU (compare 2 integers) node, based on local information.
752 // If both inputs are constants, compare them.
753 const Type* CmpUNode::sub(const Type* t1, const Type* t2) const {
754 const TypeInt* r0 = t1->is_int();
755 const TypeInt* r1 = t2->is_int();
756
757 // Check for special case in Hashtable::get - the hash index is
758 // mod'ed to the table size so the following range check is useless.
759 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have
760 // to be positive.
761 // (This is a gross hack, since the sub method never
762 // looks at the structure of the node in any other case.)
763 if (r0->_lo >= 0 && r1->_lo >= 0 && is_index_range_check()) {
764 return TypeInt::CC_LT;
765 }
766
767 if (r0->_uhi < r1->_ulo) {
768 return TypeInt::CC_LT;
769 } else if (r0->_ulo > r1->_uhi) {
770 return TypeInt::CC_GT;
771 } else if (r0->is_con() && r1->is_con()) {
772 // Since r0->_ulo == r0->_uhi == r0->get_con(), we only reach here if the constants are equal
773 assert(r0->get_con() == r1->get_con(), "must reach a previous branch otherwise");
774 return TypeInt::CC_EQ;
775 } else if (r0->_uhi == r1->_ulo) {
776 return TypeInt::CC_LE;
777 } else if (r0->_ulo == r1->_uhi) {
778 return TypeInt::CC_GE;
779 }
780
781 const Type* joined = r0->join(r1);
782 if (joined == Type::TOP) {
783 return TypeInt::CC_NE;
784 }
785
786 return TypeInt::CC;
787 }
788
789 const Type* CmpUNode::Value(PhaseGVN* phase) const {
790 const Type* t = SubNode::Value_common(phase);
791 if (t != nullptr) {
792 return t;
793 }
794 const Node* in1 = in(1);
795 const Node* in2 = in(2);
796 const Type* t1 = phase->type(in1);
797 const Type* t2 = phase->type(in2);
798 assert(t1->isa_int(), "CmpU has only Int type inputs");
799 if (t2 == TypeInt::INT) { // Compare to bottom?
800 return bottom_type();
801 }
802
803 const Type* t_sub = sub(t1, t2); // compare based on immediate inputs
804
805 uint in1_op = in1->Opcode();
806 if (in1_op == Op_AddI || in1_op == Op_SubI) {
807 // The problem rise when result of AddI(SubI) may overflow
808 // signed integer value. Let say the input type is
809 // [256, maxint] then +128 will create 2 ranges due to
810 // overflow: [minint, minint+127] and [384, maxint].
811 // But C2 type system keep only 1 type range and as result
812 // it use general [minint, maxint] for this case which we
813 // can't optimize.
814 //
815 // Make 2 separate type ranges based on types of AddI(SubI) inputs
816 // and compare results of their compare. If results are the same
817 // CmpU node can be optimized.
818 const Node* in11 = in1->in(1);
819 const Node* in12 = in1->in(2);
820 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11);
821 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12);
822 // Skip cases when input types are top or bottom.
823 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) &&
824 (t12 != Type::TOP) && (t12 != TypeInt::INT)) {
825 const TypeInt *r0 = t11->is_int();
826 const TypeInt *r1 = t12->is_int();
827 jlong lo_r0 = r0->_lo;
828 jlong hi_r0 = r0->_hi;
829 jlong lo_r1 = r1->_lo;
830 jlong hi_r1 = r1->_hi;
831 if (in1_op == Op_SubI) {
832 jlong tmp = hi_r1;
833 hi_r1 = -lo_r1;
834 lo_r1 = -tmp;
835 // Note, for substructing [minint,x] type range
836 // long arithmetic provides correct overflow answer.
837 // The confusion come from the fact that in 32-bit
838 // -minint == minint but in 64-bit -minint == maxint+1.
839 }
840 jlong lo_long = lo_r0 + lo_r1;
841 jlong hi_long = hi_r0 + hi_r1;
842 int lo_tr1 = min_jint;
843 int hi_tr1 = (int)hi_long;
844 int lo_tr2 = (int)lo_long;
845 int hi_tr2 = max_jint;
846 bool underflow = lo_long != (jlong)lo_tr2;
847 bool overflow = hi_long != (jlong)hi_tr1;
848 // Use sub(t1, t2) when there is no overflow (one type range)
849 // or when both overflow and underflow (too complex).
850 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) {
851 // Overflow only on one boundary, compare 2 separate type ranges.
852 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
853 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w);
854 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w);
855 const TypeInt* cmp1 = sub(tr1, t2)->is_int();
856 const TypeInt* cmp2 = sub(tr2, t2)->is_int();
857 // Compute union, so that cmp handles all possible results from the two cases
858 const Type* t_cmp = cmp1->meet(cmp2);
859 // Pick narrowest type, based on overflow computation and on immediate inputs
860 return t_sub->filter(t_cmp);
861 }
862 }
863 }
864
865 return t_sub;
866 }
867
868 bool CmpUNode::is_index_range_check() const {
869 // Check for the "(X ModI Y) CmpU Y" shape
870 return (in(1)->Opcode() == Op_ModI &&
871 in(1)->in(2)->eqv_uncast(in(2)));
872 }
873
874 //------------------------------Idealize---------------------------------------
875 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
876 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) {
877 switch (in(1)->Opcode()) {
878 case Op_CmpU3: // Collapse a CmpU3/CmpI into a CmpU
879 return new CmpUNode(in(1)->in(1),in(1)->in(2));
880 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL
881 return new CmpLNode(in(1)->in(1),in(1)->in(2));
882 case Op_CmpUL3: // Collapse a CmpUL3/CmpI into a CmpUL
883 return new CmpULNode(in(1)->in(1),in(1)->in(2));
884 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF
885 return new CmpFNode(in(1)->in(1),in(1)->in(2));
886 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD
887 return new CmpDNode(in(1)->in(1),in(1)->in(2));
888 //case Op_SubI:
889 // If (x - y) cannot overflow, then ((x - y) <?> 0)
890 // can be turned into (x <?> y).
891 // This is handled (with more general cases) by Ideal_sub_algebra.
892 }
893 }
894 return nullptr; // No change
895 }
896
897 //------------------------------Ideal------------------------------------------
898 Node* CmpLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
899 // Optimize expressions like
900 // CmpL(OrL(CastP2X(..), CastP2X(..)), 0L)
901 // that are used by acmp to implement a "both operands are null" check.
902 // See also the corresponding code in CmpPNode::Ideal.
903 if (can_reshape && in(1)->Opcode() == Op_OrL &&
904 in(2)->bottom_type()->is_zero_type()) {
905 for (int i = 1; i <= 2; ++i) {
906 Node* orIn = in(1)->in(i);
907 if (orIn->Opcode() == Op_CastP2X) {
908 Node* castIn = orIn->in(1);
909 if (castIn->is_InlineType()) {
910 // Replace the CastP2X by the null marker
911 InlineTypeNode* vt = castIn->as_InlineType();
912 Node* nm = phase->transform(new ConvI2LNode(vt->get_null_marker()));
913 phase->is_IterGVN()->replace_input_of(in(1), i, nm);
914 return this;
915 } else if (!phase->type(castIn)->maybe_null()) {
916 // Never null. Replace the CastP2X by constant 1L.
917 phase->is_IterGVN()->replace_input_of(in(1), i, phase->longcon(1));
918 return this;
919 }
920 }
921 }
922 }
923 const TypeLong *t2 = phase->type(in(2))->isa_long();
924 if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) {
925 const jlong con = t2->get_con();
926 if (con >= min_jint && con <= max_jint) {
927 return new CmpINode(in(1)->in(1), phase->intcon((jint)con));
928 }
929 }
930 return nullptr;
931 }
932
933 //=============================================================================
934 // Simplify a CmpL (compare 2 longs ) node, based on local information.
935 // If both inputs are constants, compare them.
936 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const {
937 const TypeLong *r0 = t1->is_long(); // Handy access
938 const TypeLong *r1 = t2->is_long();
939
940 if( r0->_hi < r1->_lo ) // Range is always low?
941 return TypeInt::CC_LT;
942 else if( r0->_lo > r1->_hi ) // Range is always high?
943 return TypeInt::CC_GT;
944
945 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
946 assert(r0->get_con() == r1->get_con(), "must be equal");
947 return TypeInt::CC_EQ; // Equal results.
948 } else if( r0->_hi == r1->_lo ) // Range is never high?
949 return TypeInt::CC_LE;
950 else if( r0->_lo == r1->_hi ) // Range is never low?
951 return TypeInt::CC_GE;
952
953 const Type* joined = r0->join(r1);
954 if (joined == Type::TOP) {
955 return TypeInt::CC_NE;
956 }
957
958 return TypeInt::CC; // else use worst case results
959 }
960
961
962 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information.
963 // If both inputs are constants, compare them.
964 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const {
965 const TypeLong* r0 = t1->is_long();
966 const TypeLong* r1 = t2->is_long();
967
968 if (r0->_uhi < r1->_ulo) {
969 return TypeInt::CC_LT;
970 } else if (r0->_ulo > r1->_uhi) {
971 return TypeInt::CC_GT;
972 } else if (r0->is_con() && r1->is_con()) {
973 // Since r0->_ulo == r0->_uhi == r0->get_con(), we only reach here if the constants are equal
974 assert(r0->get_con() == r1->get_con(), "must reach a previous branch otherwise");
975 return TypeInt::CC_EQ;
976 } else if (r0->_uhi == r1->_ulo) {
977 return TypeInt::CC_LE;
978 } else if (r0->_ulo == r1->_uhi) {
979 return TypeInt::CC_GE;
980 }
981
982 const Type* joined = r0->join(r1);
983 if (joined == Type::TOP) {
984 return TypeInt::CC_NE;
985 }
986
987 return TypeInt::CC;
988 }
989
990 //=============================================================================
991 //------------------------------sub--------------------------------------------
992 // Simplify an CmpP (compare 2 pointers) node, based on local information.
993 // If both inputs are constants, compare them.
994 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const {
995 const TypePtr *r0 = t1->is_ptr(); // Handy access
996 const TypePtr *r1 = t2->is_ptr();
997
998 // Undefined inputs makes for an undefined result
999 if( TypePtr::above_centerline(r0->_ptr) ||
1000 TypePtr::above_centerline(r1->_ptr) )
1001 return Type::TOP;
1002
1003 if (r0 == r1 && r0->singleton()) {
1004 // Equal pointer constants (klasses, nulls, etc.)
1005 return TypeInt::CC_EQ;
1006 }
1007
1008 // See if it is 2 unrelated classes.
1009 const TypeOopPtr* p0 = r0->isa_oopptr();
1010 const TypeOopPtr* p1 = r1->isa_oopptr();
1011 const TypeKlassPtr* k0 = r0->isa_klassptr();
1012 const TypeKlassPtr* k1 = r1->isa_klassptr();
1013 if ((p0 && p1) || (k0 && k1)) {
1014 if (p0 && p1) {
1015 Node* in1 = in(1)->uncast();
1016 Node* in2 = in(2)->uncast();
1017 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1);
1018 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2);
1019 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, nullptr)) {
1020 return TypeInt::CC_GT; // different pointers
1021 }
1022 }
1023 bool xklass0 = p0 ? p0->klass_is_exact() : k0->klass_is_exact();
1024 bool xklass1 = p1 ? p1->klass_is_exact() : k1->klass_is_exact();
1025 bool unrelated_classes = false;
1026
1027 if ((p0 && p0->is_same_java_type_as(p1)) ||
1028 (k0 && k0->is_same_java_type_as(k1))) {
1029 } else if ((p0 && !p1->maybe_java_subtype_of(p0) && !p0->maybe_java_subtype_of(p1)) ||
1030 (k0 && !k1->maybe_java_subtype_of(k0) && !k0->maybe_java_subtype_of(k1))) {
1031 unrelated_classes = true;
1032 } else if ((p0 && !p1->maybe_java_subtype_of(p0)) ||
1033 (k0 && !k1->maybe_java_subtype_of(k0))) {
1034 unrelated_classes = xklass1;
1035 } else if ((p0 && !p0->maybe_java_subtype_of(p1)) ||
1036 (k0 && !k0->maybe_java_subtype_of(k1))) {
1037 unrelated_classes = xklass0;
1038 }
1039 if (!unrelated_classes) {
1040 // Handle inline type arrays
1041 if ((r0->is_flat_in_array() && r1->is_not_flat_in_array()) ||
1042 (r1->is_flat_in_array() && r0->is_not_flat_in_array())) {
1043 // One type is in flat arrays but the other type is not. Must be unrelated.
1044 unrelated_classes = true;
1045 } else if ((r0->is_not_flat() && r1->is_flat()) ||
1046 (r1->is_not_flat() && r0->is_flat())) {
1047 // One type is a non-flat array and the other type is a flat array. Must be unrelated.
1048 unrelated_classes = true;
1049 } else if ((r0->is_not_null_free() && r1->is_null_free()) ||
1050 (r1->is_not_null_free() && r0->is_null_free())) {
1051 // One type is a nullable array and the other type is a null-free array. Must be unrelated.
1052 unrelated_classes = true;
1053 }
1054 }
1055 if (unrelated_classes) {
1056 // The oops classes are known to be unrelated. If the joined PTRs of
1057 // two oops is not Null and not Bottom, then we are sure that one
1058 // of the two oops is non-null, and the comparison will always fail.
1059 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
1060 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
1061 return TypeInt::CC_GT;
1062 }
1063 }
1064 }
1065
1066 // Known constants can be compared exactly
1067 // Null can be distinguished from any NotNull pointers
1068 // Unknown inputs makes an unknown result
1069 if( r0->singleton() ) {
1070 intptr_t bits0 = r0->get_con();
1071 if( r1->singleton() )
1072 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
1073 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1074 } else if( r1->singleton() ) {
1075 intptr_t bits1 = r1->get_con();
1076 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1077 } else
1078 return TypeInt::CC;
1079 }
1080
1081 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n, bool& might_be_an_array) {
1082 // Return the klass node for (indirect load from OopHandle)
1083 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
1084 // or null if not matching.
1085 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1086 n = bs->step_over_gc_barrier(n);
1087
1088 if (n->Opcode() != Op_LoadP) return nullptr;
1089
1090 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1091 if (!tp || tp->instance_klass() != phase->C->env()->Class_klass()) return nullptr;
1092
1093 Node* adr = n->in(MemNode::Address);
1094 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier.
1095 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return nullptr;
1096 adr = adr->in(MemNode::Address);
1097
1098 intptr_t off = 0;
1099 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off);
1100 if (k == nullptr) return nullptr;
1101 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr();
1102 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return nullptr;
1103 might_be_an_array |= tkp->isa_aryklassptr() || tkp->is_instklassptr()->might_be_an_array();
1104
1105 // We've found the klass node of a Java mirror load.
1106 return k;
1107 }
1108
1109 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n, bool& might_be_an_array) {
1110 // for ConP(Foo.class) return ConP(Foo.klass)
1111 // otherwise return null
1112 if (!n->is_Con()) return nullptr;
1113
1114 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1115 if (!tp) return nullptr;
1116
1117 ciType* mirror_type = tp->java_mirror_type();
1118 // TypeInstPtr::java_mirror_type() returns non-null for compile-
1119 // time Class constants only.
1120 if (!mirror_type) return nullptr;
1121
1122 // x.getClass() == int.class can never be true (for all primitive types)
1123 // Return a ConP(null) node for this case.
1124 if (mirror_type->is_classless()) {
1125 return phase->makecon(TypePtr::NULL_PTR);
1126 }
1127
1128 // return the ConP(Foo.klass)
1129 ciKlass* mirror_klass = mirror_type->as_klass();
1130
1131 if (mirror_klass->is_array_klass() && !mirror_klass->is_type_array_klass()) {
1132 if (!mirror_klass->can_be_inline_array_klass()) {
1133 // Special case for non-value arrays: They only have one (default) refined class, use it
1134 ciArrayKlass* refined_mirror_klass = ciObjArrayKlass::make(mirror_klass->as_array_klass()->element_klass(), true);
1135 return phase->makecon(TypeAryKlassPtr::make(refined_mirror_klass, Type::trust_interfaces));
1136 }
1137 might_be_an_array |= true;
1138 }
1139
1140 return phase->makecon(TypeKlassPtr::make(mirror_klass, Type::trust_interfaces));
1141 }
1142
1143 //------------------------------Ideal------------------------------------------
1144 // Normalize comparisons between Java mirror loads to compare the klass instead.
1145 //
1146 // Also check for the case of comparing an unknown klass loaded from the primary
1147 // super-type array vs a known klass with no subtypes. This amounts to
1148 // checking to see an unknown klass subtypes a known klass with no subtypes;
1149 // this only happens on an exact match. We can shorten this test by 1 load.
1150 Node* CmpPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1151 // TODO 8284443 in(1) could be cast?
1152 if (in(1)->is_InlineType() && phase->type(in(2))->is_zero_type()) {
1153 // Null checking a scalarized but nullable inline type. Check the null marker
1154 // input instead of the oop input to avoid keeping buffer allocations alive.
1155 return new CmpINode(in(1)->as_InlineType()->get_null_marker(), phase->intcon(0));
1156 }
1157 if (in(1)->is_InlineType() || in(2)->is_InlineType()) {
1158 // In C2 IR, CmpP on value objects is a pointer comparison, not a value comparison.
1159 // For non-null operands it cannot reliably be true, since their buffer oops are not
1160 // guaranteed to be identical. Therefore, the comparison can only be true when both
1161 // operands are null. Convert expressions like this to a "both operands are null" check:
1162 // CmpL(OrL(CastP2X(..), CastP2X(..)), 0L)
1163 // CmpLNode::Ideal might optimize this further to avoid keeping buffer allocations alive.
1164 Node* input[2];
1165 for (int i = 1; i <= 2; ++i) {
1166 if (in(i)->is_InlineType()) {
1167 input[i-1] = phase->transform(new ConvI2LNode(in(i)->as_InlineType()->get_null_marker()));
1168 } else {
1169 input[i-1] = phase->transform(new CastP2XNode(nullptr, in(i)));
1170 }
1171 }
1172 Node* orL = phase->transform(new OrXNode(input[0], input[1]));
1173 return new CmpXNode(orL, phase->MakeConX(0));
1174 }
1175
1176 // Normalize comparisons between Java mirrors into comparisons of the low-
1177 // level klass, where a dependent load could be shortened.
1178 //
1179 // The new pattern has a nice effect of matching the same pattern used in the
1180 // fast path of instanceof/checkcast/Class.isInstance(), which allows
1181 // redundant exact type check be optimized away by GVN.
1182 // For example, in
1183 // if (x.getClass() == Foo.class) {
1184 // Foo foo = (Foo) x;
1185 // // ... use a ...
1186 // }
1187 // a CmpPNode could be shared between if_acmpne and checkcast
1188 {
1189 bool might_be_an_array1 = false;
1190 bool might_be_an_array2 = false;
1191 Node* k1 = isa_java_mirror_load(phase, in(1), might_be_an_array1);
1192 Node* k2 = isa_java_mirror_load(phase, in(2), might_be_an_array2);
1193 Node* conk2 = isa_const_java_mirror(phase, in(2), might_be_an_array2);
1194 if (might_be_an_array1 && might_be_an_array2) {
1195 // Don't optimize if both sides might be an array because arrays with
1196 // the same Java mirror can have different refined array klasses.
1197 k1 = k2 = nullptr;
1198 }
1199
1200 if (k1 && (k2 || conk2)) {
1201 Node* lhs = k1;
1202 Node* rhs = (k2 != nullptr) ? k2 : conk2;
1203 set_req_X(1, lhs, phase);
1204 set_req_X(2, rhs, phase);
1205 return this;
1206 }
1207 }
1208
1209 // Constant pointer on right?
1210 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
1211 if (t2 == nullptr || !t2->klass_is_exact())
1212 return nullptr;
1213 // Get the constant klass we are comparing to.
1214 ciKlass* superklass = t2->exact_klass();
1215
1216 // Now check for LoadKlass on left.
1217 Node* ldk1 = in(1);
1218 if (ldk1->is_DecodeNKlass()) {
1219 ldk1 = ldk1->in(1);
1220 if (ldk1->Opcode() != Op_LoadNKlass )
1221 return nullptr;
1222 } else if (ldk1->Opcode() != Op_LoadKlass )
1223 return nullptr;
1224 // Take apart the address of the LoadKlass:
1225 Node* adr1 = ldk1->in(MemNode::Address);
1226 intptr_t con2 = 0;
1227 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
1228 if (ldk2 == nullptr)
1229 return nullptr;
1230 if (con2 == oopDesc::klass_offset_in_bytes()) {
1231 // We are inspecting an object's concrete class.
1232 // Short-circuit the check if the query is abstract.
1233 if (superklass->is_interface() ||
1234 superklass->is_abstract()) {
1235 // Make it come out always false:
1236 this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
1237 return this;
1238 }
1239 }
1240
1241 // Check for a LoadKlass from primary supertype array.
1242 // Any nested loadklass from loadklass+con must be from the p.s. array.
1243 if (ldk2->is_DecodeNKlass()) {
1244 // Keep ldk2 as DecodeN since it could be used in CmpP below.
1245 if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
1246 return nullptr;
1247 } else if (ldk2->Opcode() != Op_LoadKlass)
1248 return nullptr;
1249
1250 // Verify that we understand the situation
1251 if (con2 != (intptr_t) superklass->super_check_offset())
1252 return nullptr; // Might be element-klass loading from array klass
1253
1254 // If 'superklass' has no subklasses and is not an interface, then we are
1255 // assured that the only input which will pass the type check is
1256 // 'superklass' itself.
1257 //
1258 // We could be more liberal here, and allow the optimization on interfaces
1259 // which have a single implementor. This would require us to increase the
1260 // expressiveness of the add_dependency() mechanism.
1261 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now.
1262
1263 // Object arrays must have their base element have no subtypes
1264 while (superklass->is_obj_array_klass()) {
1265 ciType* elem = superklass->as_obj_array_klass()->element_type();
1266 superklass = elem->as_klass();
1267 }
1268 if (superklass->is_instance_klass()) {
1269 ciInstanceKlass* ik = superklass->as_instance_klass();
1270 if (ik->has_subklass() || ik->is_interface()) return nullptr;
1271 // Add a dependency if there is a chance that a subclass will be added later.
1272 if (!ik->is_final()) {
1273 phase->C->dependencies()->assert_leaf_type(ik);
1274 }
1275 }
1276
1277 // Do not fold the subtype check to an array klass pointer comparison for
1278 // value class arrays because they can have multiple refined array klasses.
1279 superklass = t2->exact_klass();
1280 assert(!superklass->is_flat_array_klass(), "Unexpected flat array klass");
1281 if (superklass->is_obj_array_klass()) {
1282 if (superklass->as_array_klass()->element_klass()->is_inlinetype() && !superklass->as_array_klass()->is_refined()) {
1283 return nullptr;
1284 } else {
1285 // Special case for non-value arrays: They only have one (default) refined class, use it
1286 set_req_X(2, phase->makecon(t2->is_aryklassptr()->cast_to_refined_array_klass_ptr()), phase);
1287 }
1288 }
1289
1290 // Bypass the dependent load, and compare directly
1291 this->set_req_X(1, ldk2, phase);
1292
1293 return this;
1294 }
1295
1296 //=============================================================================
1297 //------------------------------sub--------------------------------------------
1298 // Simplify an CmpN (compare 2 pointers) node, based on local information.
1299 // If both inputs are constants, compare them.
1300 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
1301 ShouldNotReachHere();
1302 return bottom_type();
1303 }
1304
1305 //------------------------------Ideal------------------------------------------
1306 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1307 return nullptr;
1308 }
1309
1310 //=============================================================================
1311 //------------------------------Value------------------------------------------
1312 // Simplify an CmpF (compare 2 floats ) node, based on local information.
1313 // If both inputs are constants, compare them.
1314 const Type* CmpFNode::Value(PhaseGVN* phase) const {
1315 const Node* in1 = in(1);
1316 const Node* in2 = in(2);
1317 // Either input is TOP ==> the result is TOP
1318 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1319 if( t1 == Type::TOP ) return Type::TOP;
1320 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1321 if( t2 == Type::TOP ) return Type::TOP;
1322
1323 // Not constants? Don't know squat - even if they are the same
1324 // value! If they are NaN's they compare to LT instead of EQ.
1325 const TypeF *tf1 = t1->isa_float_constant();
1326 const TypeF *tf2 = t2->isa_float_constant();
1327 if( !tf1 || !tf2 ) return TypeInt::CC;
1328
1329 // This implements the Java bytecode fcmpl, so unordered returns -1.
1330 if( tf1->is_nan() || tf2->is_nan() )
1331 return TypeInt::CC_LT;
1332
1333 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
1334 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
1335 assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
1336 return TypeInt::CC_EQ;
1337 }
1338
1339
1340 //=============================================================================
1341 //------------------------------Value------------------------------------------
1342 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
1343 // If both inputs are constants, compare them.
1344 const Type* CmpDNode::Value(PhaseGVN* phase) const {
1345 const Node* in1 = in(1);
1346 const Node* in2 = in(2);
1347 // Either input is TOP ==> the result is TOP
1348 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1349 if( t1 == Type::TOP ) return Type::TOP;
1350 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1351 if( t2 == Type::TOP ) return Type::TOP;
1352
1353 // Not constants? Don't know squat - even if they are the same
1354 // value! If they are NaN's they compare to LT instead of EQ.
1355 const TypeD *td1 = t1->isa_double_constant();
1356 const TypeD *td2 = t2->isa_double_constant();
1357 if( !td1 || !td2 ) return TypeInt::CC;
1358
1359 // This implements the Java bytecode dcmpl, so unordered returns -1.
1360 if( td1->is_nan() || td2->is_nan() )
1361 return TypeInt::CC_LT;
1362
1363 if( td1->_d < td2->_d ) return TypeInt::CC_LT;
1364 if( td1->_d > td2->_d ) return TypeInt::CC_GT;
1365 assert( td1->_d == td2->_d, "do not understand FP behavior" );
1366 return TypeInt::CC_EQ;
1367 }
1368
1369 //------------------------------Ideal------------------------------------------
1370 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
1371 // Check if we can change this to a CmpF and remove a ConvD2F operation.
1372 // Change (CMPD (F2D (float)) (ConD value))
1373 // To (CMPF (float) (ConF value))
1374 // Valid when 'value' does not lose precision as a float.
1375 // Benefits: eliminates conversion, does not require 24-bit mode
1376
1377 // NaNs prevent commuting operands. This transform works regardless of the
1378 // order of ConD and ConvF2D inputs by preserving the original order.
1379 int idx_f2d = 1; // ConvF2D on left side?
1380 if( in(idx_f2d)->Opcode() != Op_ConvF2D )
1381 idx_f2d = 2; // No, swap to check for reversed args
1382 int idx_con = 3-idx_f2d; // Check for the constant on other input
1383
1384 if( ConvertCmpD2CmpF &&
1385 in(idx_f2d)->Opcode() == Op_ConvF2D &&
1386 in(idx_con)->Opcode() == Op_ConD ) {
1387 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
1388 double t2_value_as_double = t2->_d;
1389 float t2_value_as_float = (float)t2_value_as_double;
1390 if( t2_value_as_double == (double)t2_value_as_float ) {
1391 // Test value can be represented as a float
1392 // Eliminate the conversion to double and create new comparison
1393 Node *new_in1 = in(idx_f2d)->in(1);
1394 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
1395 if( idx_f2d != 1 ) { // Must flip args to match original order
1396 Node *tmp = new_in1;
1397 new_in1 = new_in2;
1398 new_in2 = tmp;
1399 }
1400 CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
1401 ? new CmpF3Node( new_in1, new_in2 )
1402 : new CmpFNode ( new_in1, new_in2 ) ;
1403 return new_cmp; // Changed to CmpFNode
1404 }
1405 // Testing value required the precision of a double
1406 }
1407 return nullptr; // No change
1408 }
1409
1410 //=============================================================================
1411 //------------------------------Value------------------------------------------
1412 const Type* FlatArrayCheckNode::Value(PhaseGVN* phase) const {
1413 bool all_not_flat = true;
1414 for (uint i = ArrayOrKlass; i < req(); ++i) {
1415 const Type* t = phase->type(in(i));
1416 if (t == Type::TOP) {
1417 return Type::TOP;
1418 }
1419 if (t->is_ptr()->is_flat()) {
1420 // One of the input arrays is flat, check always passes
1421 return TypeInt::CC_EQ;
1422 } else if (!t->is_ptr()->is_not_flat()) {
1423 // One of the input arrays might be flat
1424 all_not_flat = false;
1425 }
1426 }
1427 if (all_not_flat) {
1428 // None of the input arrays can be flat, check always fails
1429 return TypeInt::CC_GT;
1430 }
1431 return TypeInt::CC;
1432 }
1433
1434 //------------------------------Ideal------------------------------------------
1435 Node* FlatArrayCheckNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1436 bool changed = false;
1437 // Remove inputs that are known to be non-flat
1438 for (uint i = ArrayOrKlass; i < req(); ++i) {
1439 const Type* t = phase->type(in(i));
1440 if (t->isa_ptr() && t->is_ptr()->is_not_flat()) {
1441 del_req(i--);
1442 changed = true;
1443 }
1444 }
1445 return changed ? this : nullptr;
1446 }
1447
1448 //=============================================================================
1449 //------------------------------cc2logical-------------------------------------
1450 // Convert a condition code type to a logical type
1451 const Type *BoolTest::cc2logical( const Type *CC ) const {
1452 if( CC == Type::TOP ) return Type::TOP;
1453 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
1454 const TypeInt *ti = CC->is_int();
1455 if( ti->is_con() ) { // Only 1 kind of condition codes set?
1456 // Match low order 2 bits
1457 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
1458 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result
1459 return TypeInt::make(tmp); // Boolean result
1460 }
1461
1462 if( CC == TypeInt::CC_GE ) {
1463 if( _test == ge ) return TypeInt::ONE;
1464 if( _test == lt ) return TypeInt::ZERO;
1465 }
1466 if( CC == TypeInt::CC_LE ) {
1467 if( _test == le ) return TypeInt::ONE;
1468 if( _test == gt ) return TypeInt::ZERO;
1469 }
1470 if( CC == TypeInt::CC_NE ) {
1471 if( _test == ne ) return TypeInt::ONE;
1472 if( _test == eq ) return TypeInt::ZERO;
1473 }
1474
1475 return TypeInt::BOOL;
1476 }
1477
1478 BoolTest::mask BoolTest::unsigned_mask(BoolTest::mask btm) {
1479 switch(btm) {
1480 case eq:
1481 case ne:
1482 return btm;
1483 case lt:
1484 case le:
1485 case gt:
1486 case ge:
1487 return mask(btm | unsigned_compare);
1488 default:
1489 ShouldNotReachHere();
1490 }
1491 }
1492
1493 //------------------------------dump_spec-------------------------------------
1494 // Print special per-node info
1495 void BoolTest::dump_on(outputStream *st) const {
1496 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"};
1497 st->print("%s", msg[_test]);
1498 }
1499
1500 // Returns the logical AND of two tests (or 'never' if both tests can never be true).
1501 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'.
1502 BoolTest::mask BoolTest::merge(BoolTest other) const {
1503 const mask res[illegal+1][illegal+1] = {
1504 // eq, gt, of, lt, ne, le, nof, ge, never, illegal
1505 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq
1506 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt
1507 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of
1508 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt
1509 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne
1510 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le
1511 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof
1512 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge
1513 {never, never, never, never, never, never, never, never, never, illegal}, // never
1514 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal
1515 return res[_test][other._test];
1516 }
1517
1518 //=============================================================================
1519 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
1520 uint BoolNode::size_of() const { return sizeof(BoolNode); }
1521
1522 //------------------------------operator==-------------------------------------
1523 bool BoolNode::cmp( const Node &n ) const {
1524 const BoolNode *b = (const BoolNode *)&n; // Cast up
1525 return (_test._test == b->_test._test);
1526 }
1527
1528 //-------------------------------make_predicate--------------------------------
1529 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1530 if (test_value->is_Con()) return test_value;
1531 if (test_value->is_Bool()) return test_value;
1532 if (test_value->is_CMove() &&
1533 test_value->in(CMoveNode::Condition)->is_Bool()) {
1534 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool();
1535 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1536 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1537 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1538 return bol;
1539 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1540 return phase->transform( bol->negate(phase) );
1541 }
1542 // Else fall through. The CMove gets in the way of the test.
1543 // It should be the case that make_predicate(bol->as_int_value()) == bol.
1544 }
1545 Node* cmp = new CmpINode(test_value, phase->intcon(0));
1546 cmp = phase->transform(cmp);
1547 Node* bol = new BoolNode(cmp, BoolTest::ne);
1548 return phase->transform(bol);
1549 }
1550
1551 //--------------------------------as_int_value---------------------------------
1552 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1553 // Inverse to make_predicate. The CMove probably boils down to a Conv2B.
1554 Node* cmov = CMoveNode::make(this, phase->intcon(0), phase->intcon(1), TypeInt::BOOL);
1555 return phase->transform(cmov);
1556 }
1557
1558 //----------------------------------negate-------------------------------------
1559 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1560 return new BoolNode(in(1), _test.negate());
1561 }
1562
1563 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub
1564 // overflows and we can prove that C is not in the two resulting ranges.
1565 // This optimization is similar to the one performed by CmpUNode::Value().
1566 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op,
1567 int cmp1_op, const TypeInt* cmp2_type) {
1568 // Only optimize eq/ne integer comparison of add/sub
1569 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1570 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) {
1571 // Skip cases were inputs of add/sub are not integers or of bottom type
1572 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int();
1573 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int();
1574 if ((r0 != nullptr) && (r0 != TypeInt::INT) &&
1575 (r1 != nullptr) && (r1 != TypeInt::INT) &&
1576 (cmp2_type != TypeInt::INT)) {
1577 // Compute exact (long) type range of add/sub result
1578 jlong lo_long = r0->_lo;
1579 jlong hi_long = r0->_hi;
1580 if (cmp1_op == Op_AddI) {
1581 lo_long += r1->_lo;
1582 hi_long += r1->_hi;
1583 } else {
1584 lo_long -= r1->_hi;
1585 hi_long -= r1->_lo;
1586 }
1587 // Check for over-/underflow by casting to integer
1588 int lo_int = (int)lo_long;
1589 int hi_int = (int)hi_long;
1590 bool underflow = lo_long != (jlong)lo_int;
1591 bool overflow = hi_long != (jlong)hi_int;
1592 if ((underflow != overflow) && (hi_int < lo_int)) {
1593 // Overflow on one boundary, compute resulting type ranges:
1594 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT]
1595 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
1596 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w);
1597 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w);
1598 // Compare second input of cmp to both type ranges
1599 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type);
1600 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type);
1601 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) {
1602 // The result of the add/sub will never equal cmp2. Replace BoolNode
1603 // by false (0) if it tests for equality and by true (1) otherwise.
1604 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1);
1605 }
1606 }
1607 }
1608 }
1609 return nullptr;
1610 }
1611
1612 static bool is_counted_loop_cmp(Node *cmp) {
1613 Node *n = cmp->in(1)->in(1);
1614 return n != nullptr &&
1615 n->is_Phi() &&
1616 n->in(0) != nullptr &&
1617 n->in(0)->is_CountedLoop() &&
1618 n->in(0)->as_CountedLoop()->phi() == n;
1619 }
1620
1621 //------------------------------Ideal------------------------------------------
1622 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1623 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1624 // This moves the constant to the right. Helps value-numbering.
1625 Node *cmp = in(1);
1626 if( !cmp->is_Sub() ) return nullptr;
1627 int cop = cmp->Opcode();
1628 if( cop == Op_FastLock || cop == Op_FastUnlock ||
1629 cmp->is_SubTypeCheck() || cop == Op_VectorTest ) {
1630 return nullptr;
1631 }
1632 Node *cmp1 = cmp->in(1);
1633 Node *cmp2 = cmp->in(2);
1634 if( !cmp1 ) return nullptr;
1635
1636 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) {
1637 return nullptr;
1638 }
1639
1640 const int cmp1_op = cmp1->Opcode();
1641 const int cmp2_op = cmp2->Opcode();
1642
1643 // Constant on left?
1644 Node *con = cmp1;
1645 // Move constants to the right of compare's to canonicalize.
1646 // Do not muck with Opaque1 nodes, as this indicates a loop
1647 // guard that cannot change shape.
1648 if (con->is_Con() && !cmp2->is_Con() && cmp2_op != Op_OpaqueZeroTripGuard &&
1649 // Because of NaN's, CmpD and CmpF are not commutative
1650 cop != Op_CmpD && cop != Op_CmpF &&
1651 // Protect against swapping inputs to a compare when it is used by a
1652 // counted loop exit, which requires maintaining the loop-limit as in(2)
1653 !is_counted_loop_exit_test() ) {
1654 // Ok, commute the constant to the right of the cmp node.
1655 // Clone the Node, getting a new Node of the same class
1656 cmp = cmp->clone();
1657 // Swap inputs to the clone
1658 cmp->swap_edges(1, 2);
1659 cmp = phase->transform( cmp );
1660 return new BoolNode( cmp, _test.commute() );
1661 }
1662
1663 // Change "bool eq/ne (cmp (cmove (bool tst (cmp2)) 1 0) 0)" into "bool tst/~tst (cmp2)"
1664 if (cop == Op_CmpI &&
1665 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1666 cmp1_op == Op_CMoveI && cmp2->find_int_con(1) == 0) {
1667 // 0 should be on the true branch
1668 if (cmp1->in(CMoveNode::Condition)->is_Bool() &&
1669 cmp1->in(CMoveNode::IfTrue)->find_int_con(1) == 0 &&
1670 cmp1->in(CMoveNode::IfFalse)->find_int_con(0) != 0) {
1671 BoolNode* target = cmp1->in(CMoveNode::Condition)->as_Bool();
1672 return new BoolNode(target->in(1),
1673 (_test._test == BoolTest::eq) ? target->_test._test :
1674 target->_test.negate());
1675 }
1676 }
1677
1678 // Change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1679 if (cop == Op_CmpI &&
1680 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1681 cmp1_op == Op_AndI && cmp2_op == Op_ConI &&
1682 cmp1->in(2)->Opcode() == Op_ConI) {
1683 const TypeInt *t12 = phase->type(cmp2)->isa_int();
1684 const TypeInt *t112 = phase->type(cmp1->in(2))->isa_int();
1685 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1686 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1687 Node *ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1688 return new BoolNode(ncmp, _test.negate());
1689 }
1690 }
1691
1692 // Same for long type: change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1693 if (cop == Op_CmpL &&
1694 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1695 cmp1_op == Op_AndL && cmp2_op == Op_ConL &&
1696 cmp1->in(2)->Opcode() == Op_ConL) {
1697 const TypeLong *t12 = phase->type(cmp2)->isa_long();
1698 const TypeLong *t112 = phase->type(cmp1->in(2))->isa_long();
1699 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1700 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1701 Node *ncmp = phase->transform(new CmpLNode(cmp1, phase->longcon(0)));
1702 return new BoolNode(ncmp, _test.negate());
1703 }
1704 }
1705
1706 // Change "cmp (add X min_jint) (add Y min_jint)" into "cmpu X Y"
1707 // and "cmp (add X min_jint) c" into "cmpu X (c + min_jint)"
1708 if (cop == Op_CmpI &&
1709 cmp1_op == Op_AddI &&
1710 phase->type(cmp1->in(2)) == TypeInt::MIN &&
1711 !is_cloop_condition(this)) {
1712 if (cmp2_op == Op_ConI) {
1713 Node* ncmp2 = phase->intcon(java_add(cmp2->get_int(), min_jint));
1714 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), ncmp2));
1715 return new BoolNode(ncmp, _test._test);
1716 } else if (cmp2_op == Op_AddI &&
1717 phase->type(cmp2->in(2)) == TypeInt::MIN &&
1718 !is_cloop_condition(this)) {
1719 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), cmp2->in(1)));
1720 return new BoolNode(ncmp, _test._test);
1721 }
1722 }
1723
1724 // Change "cmp (add X min_jlong) (add Y min_jlong)" into "cmpu X Y"
1725 // and "cmp (add X min_jlong) c" into "cmpu X (c + min_jlong)"
1726 if (cop == Op_CmpL &&
1727 cmp1_op == Op_AddL &&
1728 phase->type(cmp1->in(2)) == TypeLong::MIN &&
1729 !is_cloop_condition(this)) {
1730 if (cmp2_op == Op_ConL) {
1731 Node* ncmp2 = phase->longcon(java_add(cmp2->get_long(), min_jlong));
1732 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), ncmp2));
1733 return new BoolNode(ncmp, _test._test);
1734 } else if (cmp2_op == Op_AddL &&
1735 phase->type(cmp2->in(2)) == TypeLong::MIN &&
1736 !is_cloop_condition(this)) {
1737 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), cmp2->in(1)));
1738 return new BoolNode(ncmp, _test._test);
1739 }
1740 }
1741
1742 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1743 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the
1744 // test instead.
1745 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1746 if (cmp2_type == nullptr) return nullptr;
1747 Node* j_xor = cmp1;
1748 if( cmp2_type == TypeInt::ZERO &&
1749 cmp1_op == Op_XorI &&
1750 j_xor->in(1) != j_xor && // An xor of itself is dead
1751 phase->type( j_xor->in(1) ) == TypeInt::BOOL &&
1752 phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1753 (_test._test == BoolTest::eq ||
1754 _test._test == BoolTest::ne) ) {
1755 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2));
1756 return new BoolNode( ncmp, _test.negate() );
1757 }
1758
1759 // Transform: "((x & (m - 1)) <u m)" or "(((m - 1) & x) <u m)" into "(m >u 0)"
1760 // This is case [CMPU_MASK] which is further described at the method comment of BoolNode::Value_cmpu_and_mask().
1761 if (cop == Op_CmpU && _test._test == BoolTest::lt && cmp1_op == Op_AndI) {
1762 Node* m = cmp2; // RHS: m
1763 for (int add_idx = 1; add_idx <= 2; add_idx++) { // LHS: "(m + (-1)) & x" or "x & (m + (-1))"?
1764 Node* maybe_m_minus_1 = cmp1->in(add_idx);
1765 if (maybe_m_minus_1->Opcode() == Op_AddI &&
1766 maybe_m_minus_1->in(2)->find_int_con(0) == -1 &&
1767 maybe_m_minus_1->in(1) == m) {
1768 Node* m_cmpu_0 = phase->transform(new CmpUNode(m, phase->intcon(0)));
1769 return new BoolNode(m_cmpu_0, BoolTest::gt);
1770 }
1771 }
1772 }
1773
1774 // Change x u< 1 or x u<= 0 to x == 0
1775 // and x u> 0 or u>= 1 to x != 0
1776 if (cop == Op_CmpU &&
1777 cmp1_op != Op_LoadRange &&
1778 (((_test._test == BoolTest::lt || _test._test == BoolTest::ge) &&
1779 cmp2->find_int_con(-1) == 1) ||
1780 ((_test._test == BoolTest::le || _test._test == BoolTest::gt) &&
1781 cmp2->find_int_con(-1) == 0))) {
1782 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1783 return new BoolNode(ncmp, _test.is_less() ? BoolTest::eq : BoolTest::ne);
1784 }
1785
1786 // Change (arraylength <= 0) or (arraylength == 0)
1787 // into (arraylength u<= 0)
1788 // Also change (arraylength != 0) into (arraylength u> 0)
1789 // The latter version matches the code pattern generated for
1790 // array range checks, which will more likely be optimized later.
1791 if (cop == Op_CmpI &&
1792 cmp1_op == Op_LoadRange &&
1793 cmp2->find_int_con(-1) == 0) {
1794 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) {
1795 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1796 return new BoolNode(ncmp, BoolTest::le);
1797 } else if (_test._test == BoolTest::ne) {
1798 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1799 return new BoolNode(ncmp, BoolTest::gt);
1800 }
1801 }
1802
1803 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1804 // This is a standard idiom for branching on a boolean value.
1805 Node *c2b = cmp1;
1806 if( cmp2_type == TypeInt::ZERO &&
1807 cmp1_op == Op_Conv2B &&
1808 (_test._test == BoolTest::eq ||
1809 _test._test == BoolTest::ne) ) {
1810 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1811 ? (Node*)new CmpINode(c2b->in(1),cmp2)
1812 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1813 );
1814 return new BoolNode( ncmp, _test._test );
1815 }
1816
1817 // Comparing a SubI against a zero is equal to comparing the SubI
1818 // arguments directly. This only works for eq and ne comparisons
1819 // due to possible integer overflow.
1820 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1821 (cop == Op_CmpI) &&
1822 (cmp1_op == Op_SubI) &&
1823 ( cmp2_type == TypeInt::ZERO ) ) {
1824 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2)));
1825 return new BoolNode( ncmp, _test._test );
1826 }
1827
1828 // Same as above but with and AddI of a constant
1829 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1830 cop == Op_CmpI &&
1831 cmp1_op == Op_AddI &&
1832 cmp1->in(2) != nullptr &&
1833 phase->type(cmp1->in(2))->isa_int() &&
1834 phase->type(cmp1->in(2))->is_int()->is_con() &&
1835 cmp2_type == TypeInt::ZERO &&
1836 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape
1837 ) {
1838 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int();
1839 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi)));
1840 return new BoolNode( ncmp, _test._test );
1841 }
1842
1843 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)"
1844 // since zero check of conditional negation of an integer is equal to
1845 // zero check of the integer directly.
1846 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1847 (cop == Op_CmpI) &&
1848 (cmp2_type == TypeInt::ZERO) &&
1849 (cmp1_op == Op_Phi)) {
1850 // There should be a diamond phi with true path at index 1 or 2
1851 PhiNode *phi = cmp1->as_Phi();
1852 int idx_true = phi->is_diamond_phi();
1853 if (idx_true != 0) {
1854 // True input is in(idx_true) while false input is in(3 - idx_true)
1855 Node *tin = phi->in(idx_true);
1856 Node *fin = phi->in(3 - idx_true);
1857 if ((tin->Opcode() == Op_SubI) &&
1858 (phase->type(tin->in(1)) == TypeInt::ZERO) &&
1859 (tin->in(2) == fin)) {
1860 // Found conditional negation at true path, create a new CmpINode without that
1861 Node *ncmp = phase->transform(new CmpINode(fin, cmp2));
1862 return new BoolNode(ncmp, _test._test);
1863 }
1864 if ((fin->Opcode() == Op_SubI) &&
1865 (phase->type(fin->in(1)) == TypeInt::ZERO) &&
1866 (fin->in(2) == tin)) {
1867 // Found conditional negation at false path, create a new CmpINode without that
1868 Node *ncmp = phase->transform(new CmpINode(tin, cmp2));
1869 return new BoolNode(ncmp, _test._test);
1870 }
1871 }
1872 }
1873
1874 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the
1875 // most general case because negating 0x80000000 does nothing. Needed for
1876 // the CmpF3/SubI/CmpI idiom.
1877 if( cop == Op_CmpI &&
1878 cmp1_op == Op_SubI &&
1879 cmp2_type == TypeInt::ZERO &&
1880 phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1881 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1882 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2));
1883 return new BoolNode( ncmp, _test.commute() );
1884 }
1885
1886 // Try to optimize signed integer comparison
1887 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type);
1888
1889 // The transformation below is not valid for either signed or unsigned
1890 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1891 // This transformation can be resurrected when we are able to
1892 // make inferences about the range of values being subtracted from
1893 // (or added to) relative to the wraparound point.
1894 //
1895 // // Remove +/-1's if possible.
1896 // // "X <= Y-1" becomes "X < Y"
1897 // // "X+1 <= Y" becomes "X < Y"
1898 // // "X < Y+1" becomes "X <= Y"
1899 // // "X-1 < Y" becomes "X <= Y"
1900 // // Do not this to compares off of the counted-loop-end. These guys are
1901 // // checking the trip counter and they want to use the post-incremented
1902 // // counter. If they use the PRE-incremented counter, then the counter has
1903 // // to be incremented in a private block on a loop backedge.
1904 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1905 // return nullptr;
1906 // #ifndef PRODUCT
1907 // // Do not do this in a wash GVN pass during verification.
1908 // // Gets triggered by too many simple optimizations to be bothered with
1909 // // re-trying it again and again.
1910 // if( !phase->allow_progress() ) return nullptr;
1911 // #endif
1912 // // Not valid for unsigned compare because of corner cases in involving zero.
1913 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1914 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1915 // // "0 <=u Y" is always true).
1916 // if( cmp->Opcode() == Op_CmpU ) return nullptr;
1917 // int cmp2_op = cmp2->Opcode();
1918 // if( _test._test == BoolTest::le ) {
1919 // if( cmp1_op == Op_AddI &&
1920 // phase->type( cmp1->in(2) ) == TypeInt::ONE )
1921 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1922 // else if( cmp2_op == Op_AddI &&
1923 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1924 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1925 // } else if( _test._test == BoolTest::lt ) {
1926 // if( cmp1_op == Op_AddI &&
1927 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1928 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1929 // else if( cmp2_op == Op_AddI &&
1930 // phase->type( cmp2->in(2) ) == TypeInt::ONE )
1931 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1932 // }
1933 }
1934
1935 // We use the following Lemmas/insights for the following two transformations (1) and (2):
1936 // x & y <=u y, for any x and y (Lemma 1, masking always results in a smaller unsigned number)
1937 // y <u y + 1 is always true if y != -1 (Lemma 2, (uint)(-1 + 1) == (uint)(UINT_MAX + 1) which overflows)
1938 // y <u 0 is always false for any y (Lemma 3, 0 == UINT_MIN and nothing can be smaller than that)
1939 //
1940 // (1a) Always: Change ((x & m) <=u m ) or ((m & x) <=u m ) to always true (true by Lemma 1)
1941 // (1b) If m != -1: Change ((x & m) <u m + 1) or ((m & x) <u m + 1) to always true:
1942 // x & m <=u m is always true // (Lemma 1)
1943 // x & m <=u m <u m + 1 is always true // (Lemma 2: m <u m + 1, if m != -1)
1944 //
1945 // A counter example for (1b), if we allowed m == -1:
1946 // (x & m) <u m + 1
1947 // (x & -1) <u 0
1948 // x <u 0
1949 // which is false for any x (Lemma 3)
1950 //
1951 // (2) Change ((x & (m - 1)) <u m) or (((m - 1) & x) <u m) to (m >u 0)
1952 // This is the off-by-one variant of the above.
1953 //
1954 // We now prove that this replacement is correct. This is the same as proving
1955 // "m >u 0" if and only if "x & (m - 1) <u m", i.e. "m >u 0 <=> x & (m - 1) <u m"
1956 //
1957 // We use (Lemma 1) and (Lemma 3) from above.
1958 //
1959 // Case "x & (m - 1) <u m => m >u 0":
1960 // We prove this by contradiction:
1961 // Assume m <=u 0 which is equivalent to m == 0:
1962 // and thus
1963 // x & (m - 1) <u m = 0 // m == 0
1964 // y <u 0 // y = x & (m - 1)
1965 // by Lemma 3, this is always false, i.e. a contradiction to our assumption.
1966 //
1967 // Case "m >u 0 => x & (m - 1) <u m":
1968 // x & (m - 1) <=u (m - 1) // (Lemma 1)
1969 // x & (m - 1) <=u (m - 1) <u m // Using assumption m >u 0, no underflow of "m - 1"
1970 //
1971 //
1972 // Note that the signed version of "m > 0":
1973 // m > 0 <=> x & (m - 1) <u m
1974 // does not hold:
1975 // Assume m == -1 and x == -1:
1976 // x & (m - 1) <u m
1977 // -1 & -2 <u -1
1978 // -2 <u -1
1979 // UINT_MAX - 1 <u UINT_MAX // Signed to unsigned numbers
1980 // which is true while
1981 // m > 0
1982 // is false which is a contradiction.
1983 //
1984 // (1a) and (1b) is covered by this method since we can directly return a true value as type while (2) is covered
1985 // in BoolNode::Ideal since we create a new non-constant node (see [CMPU_MASK]).
1986 const Type* BoolNode::Value_cmpu_and_mask(PhaseValues* phase) const {
1987 Node* cmp = in(1);
1988 if (cmp != nullptr && cmp->Opcode() == Op_CmpU) {
1989 Node* cmp1 = cmp->in(1);
1990 Node* cmp2 = cmp->in(2);
1991
1992 if (cmp1->Opcode() == Op_AndI) {
1993 Node* m = nullptr;
1994 if (_test._test == BoolTest::le) {
1995 // (1a) "((x & m) <=u m)", cmp2 = m
1996 m = cmp2;
1997 } else if (_test._test == BoolTest::lt && cmp2->Opcode() == Op_AddI && cmp2->in(2)->find_int_con(0) == 1) {
1998 // (1b) "(x & m) <u m + 1" and "(m & x) <u m + 1", cmp2 = m + 1
1999 Node* rhs_m = cmp2->in(1);
2000 const TypeInt* rhs_m_type = phase->type(rhs_m)->isa_int();
2001 if (rhs_m_type != nullptr && (rhs_m_type->_lo > -1 || rhs_m_type->_hi < -1)) {
2002 // Exclude any case where m == -1 is possible.
2003 m = rhs_m;
2004 }
2005 }
2006
2007 if (cmp1->in(2) == m || cmp1->in(1) == m) {
2008 return TypeInt::ONE;
2009 }
2010 }
2011 }
2012
2013 return nullptr;
2014 }
2015
2016 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
2017 // based on local information. If the input is constant, do it.
2018 const Type* BoolNode::Value(PhaseGVN* phase) const {
2019 const Type* input_type = phase->type(in(1));
2020 if (input_type == Type::TOP) {
2021 return Type::TOP;
2022 }
2023 const Type* t = Value_cmpu_and_mask(phase);
2024 if (t != nullptr) {
2025 return t;
2026 }
2027
2028 return _test.cc2logical(input_type);
2029 }
2030
2031 #ifndef PRODUCT
2032 //------------------------------dump_spec--------------------------------------
2033 // Dump special per-node info
2034 void BoolNode::dump_spec(outputStream *st) const {
2035 st->print("[");
2036 _test.dump_on(st);
2037 st->print("]");
2038 }
2039 #endif
2040
2041 //----------------------is_counted_loop_exit_test------------------------------
2042 // Returns true if node is used by a counted loop node.
2043 bool BoolNode::is_counted_loop_exit_test() {
2044 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
2045 Node* use = fast_out(i);
2046 if (use->is_CountedLoopEnd()) {
2047 return true;
2048 }
2049 }
2050 return false;
2051 }
2052
2053 //=============================================================================
2054 //------------------------------Value------------------------------------------
2055 const Type* AbsNode::Value(PhaseGVN* phase) const {
2056 const Type* t1 = phase->type(in(1));
2057 if (t1 == Type::TOP) return Type::TOP;
2058
2059 switch (t1->base()) {
2060 case Type::Int: {
2061 const TypeInt* ti = t1->is_int();
2062 if (ti->is_con()) {
2063 return TypeInt::make(g_uabs(ti->get_con()));
2064 }
2065 break;
2066 }
2067 case Type::Long: {
2068 const TypeLong* tl = t1->is_long();
2069 if (tl->is_con()) {
2070 return TypeLong::make(g_uabs(tl->get_con()));
2071 }
2072 break;
2073 }
2074 case Type::FloatCon:
2075 return TypeF::make(abs(t1->getf()));
2076 case Type::DoubleCon:
2077 return TypeD::make(abs(t1->getd()));
2078 default:
2079 break;
2080 }
2081
2082 return bottom_type();
2083 }
2084
2085 //------------------------------Identity----------------------------------------
2086 Node* AbsNode::Identity(PhaseGVN* phase) {
2087 Node* in1 = in(1);
2088 // No need to do abs for non-negative values
2089 if (phase->type(in1)->higher_equal(TypeInt::POS) ||
2090 phase->type(in1)->higher_equal(TypeLong::POS)) {
2091 return in1;
2092 }
2093 // Convert "abs(abs(x))" into "abs(x)"
2094 if (in1->Opcode() == Opcode()) {
2095 return in1;
2096 }
2097 return this;
2098 }
2099
2100 //------------------------------Ideal------------------------------------------
2101 Node* AbsNode::Ideal(PhaseGVN* phase, bool can_reshape) {
2102 Node* in1 = in(1);
2103 // Convert "abs(0-x)" into "abs(x)"
2104 if (in1->is_Sub() && phase->type(in1->in(1))->is_zero_type()) {
2105 set_req_X(1, in1->in(2), phase);
2106 return this;
2107 }
2108 return nullptr;
2109 }
2110
2111 //=============================================================================
2112 //------------------------------Value------------------------------------------
2113 // Compute sqrt
2114 const Type* SqrtDNode::Value(PhaseGVN* phase) const {
2115 const Type *t1 = phase->type( in(1) );
2116 if( t1 == Type::TOP ) return Type::TOP;
2117 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
2118 double d = t1->getd();
2119 if( d < 0.0 ) return Type::DOUBLE;
2120 return TypeD::make( sqrt( d ) );
2121 }
2122
2123 const Type* SqrtFNode::Value(PhaseGVN* phase) const {
2124 const Type *t1 = phase->type( in(1) );
2125 if( t1 == Type::TOP ) return Type::TOP;
2126 if( t1->base() != Type::FloatCon ) return Type::FLOAT;
2127 float f = t1->getf();
2128 if( f < 0.0f ) return Type::FLOAT;
2129 return TypeF::make( (float)sqrt( (double)f ) );
2130 }
2131
2132 const Type* SqrtHFNode::Value(PhaseGVN* phase) const {
2133 const Type* t1 = phase->type(in(1));
2134 if (t1 == Type::TOP) { return Type::TOP; }
2135 if (t1->base() != Type::HalfFloatCon) { return Type::HALF_FLOAT; }
2136 float f = t1->getf();
2137 if (f < 0.0f) return Type::HALF_FLOAT;
2138 return TypeH::make((float)sqrt((double)f));
2139 }
2140
2141 static const Type* reverse_bytes(int opcode, const Type* con) {
2142 switch (opcode) {
2143 // It is valid in bytecode to load any int and pass it to a method that expects a smaller type (i.e., short, char).
2144 // Let's cast the value to match the Java behavior.
2145 case Op_ReverseBytesS: return TypeInt::make(byteswap(static_cast<jshort>(con->is_int()->get_con())));
2146 case Op_ReverseBytesUS: return TypeInt::make(byteswap(static_cast<jchar>(con->is_int()->get_con())));
2147 case Op_ReverseBytesI: return TypeInt::make(byteswap(con->is_int()->get_con()));
2148 case Op_ReverseBytesL: return TypeLong::make(byteswap(con->is_long()->get_con()));
2149 default: ShouldNotReachHere();
2150 }
2151 }
2152
2153 const Type* ReverseBytesNode::Value(PhaseGVN* phase) const {
2154 const Type* type = phase->type(in(1));
2155 if (type == Type::TOP) {
2156 return Type::TOP;
2157 }
2158 if (type->singleton()) {
2159 return reverse_bytes(Opcode(), type);
2160 }
2161 return bottom_type();
2162 }
2163
2164 const Type* ReverseINode::Value(PhaseGVN* phase) const {
2165 const Type *t1 = phase->type( in(1) );
2166 if (t1 == Type::TOP) {
2167 return Type::TOP;
2168 }
2169 const TypeInt* t1int = t1->isa_int();
2170 if (t1int && t1int->is_con()) {
2171 jint res = reverse_bits(t1int->get_con());
2172 return TypeInt::make(res);
2173 }
2174 return bottom_type();
2175 }
2176
2177 const Type* ReverseLNode::Value(PhaseGVN* phase) const {
2178 const Type *t1 = phase->type( in(1) );
2179 if (t1 == Type::TOP) {
2180 return Type::TOP;
2181 }
2182 const TypeLong* t1long = t1->isa_long();
2183 if (t1long && t1long->is_con()) {
2184 jlong res = reverse_bits(t1long->get_con());
2185 return TypeLong::make(res);
2186 }
2187 return bottom_type();
2188 }
2189
2190 Node* ReverseINode::Identity(PhaseGVN* phase) {
2191 if (in(1)->Opcode() == Op_ReverseI) {
2192 return in(1)->in(1);
2193 }
2194 return this;
2195 }
2196
2197 Node* ReverseLNode::Identity(PhaseGVN* phase) {
2198 if (in(1)->Opcode() == Op_ReverseL) {
2199 return in(1)->in(1);
2200 }
2201 return this;
2202 }