1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
24
25 #include "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 assert(!t1->isa_ptr(), "obsolete usage of CmpU");
755
756 // comparing two unsigned ints
757 const TypeInt *r0 = t1->is_int(); // Handy access
758 const TypeInt *r1 = t2->is_int();
759
760 // Current installed version
761 // Compare ranges for non-overlap
762 juint lo0 = r0->_lo;
763 juint hi0 = r0->_hi;
764 juint lo1 = r1->_lo;
765 juint hi1 = r1->_hi;
766
767 // If either one has both negative and positive values,
768 // it therefore contains both 0 and -1, and since [0..-1] is the
769 // full unsigned range, the type must act as an unsigned bottom.
770 bool bot0 = ((jint)(lo0 ^ hi0) < 0);
771 bool bot1 = ((jint)(lo1 ^ hi1) < 0);
772
773 if (bot0 || bot1) {
774 // All unsigned values are LE -1 and GE 0.
775 if (lo0 == 0 && hi0 == 0) {
776 return TypeInt::CC_LE; // 0 <= bot
777 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) {
778 return TypeInt::CC_GE; // -1 >= bot
779 } else if (lo1 == 0 && hi1 == 0) {
780 return TypeInt::CC_GE; // bot >= 0
781 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) {
782 return TypeInt::CC_LE; // bot <= -1
783 }
784 } else {
785 // We can use ranges of the form [lo..hi] if signs are the same.
786 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
787 // results are reversed, '-' > '+' for unsigned compare
788 if (hi0 < lo1) {
789 return TypeInt::CC_LT; // smaller
790 } else if (lo0 > hi1) {
791 return TypeInt::CC_GT; // greater
792 } else if (hi0 == lo1 && lo0 == hi1) {
793 return TypeInt::CC_EQ; // Equal results
794 } else if (lo0 >= hi1) {
795 return TypeInt::CC_GE;
796 } else if (hi0 <= lo1) {
797 // Check for special case in Hashtable::get. (See below.)
798 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
799 return TypeInt::CC_LT;
800 return TypeInt::CC_LE;
801 }
802 }
803 // Check for special case in Hashtable::get - the hash index is
804 // mod'ed to the table size so the following range check is useless.
805 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have
806 // to be positive.
807 // (This is a gross hack, since the sub method never
808 // looks at the structure of the node in any other case.)
809 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
810 return TypeInt::CC_LT;
811
812 const Type* joined = r0->join(r1);
813 if (joined == Type::TOP) {
814 return TypeInt::CC_NE;
815 }
816
817 return TypeInt::CC; // else use worst case results
818 }
819
820 const Type* CmpUNode::Value(PhaseGVN* phase) const {
821 const Type* t = SubNode::Value_common(phase);
822 if (t != nullptr) {
823 return t;
824 }
825 const Node* in1 = in(1);
826 const Node* in2 = in(2);
827 const Type* t1 = phase->type(in1);
828 const Type* t2 = phase->type(in2);
829 assert(t1->isa_int(), "CmpU has only Int type inputs");
830 if (t2 == TypeInt::INT) { // Compare to bottom?
831 return bottom_type();
832 }
833
834 const Type* t_sub = sub(t1, t2); // compare based on immediate inputs
835
836 uint in1_op = in1->Opcode();
837 if (in1_op == Op_AddI || in1_op == Op_SubI) {
838 // The problem rise when result of AddI(SubI) may overflow
839 // signed integer value. Let say the input type is
840 // [256, maxint] then +128 will create 2 ranges due to
841 // overflow: [minint, minint+127] and [384, maxint].
842 // But C2 type system keep only 1 type range and as result
843 // it use general [minint, maxint] for this case which we
844 // can't optimize.
845 //
846 // Make 2 separate type ranges based on types of AddI(SubI) inputs
847 // and compare results of their compare. If results are the same
848 // CmpU node can be optimized.
849 const Node* in11 = in1->in(1);
850 const Node* in12 = in1->in(2);
851 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11);
852 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12);
853 // Skip cases when input types are top or bottom.
854 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) &&
855 (t12 != Type::TOP) && (t12 != TypeInt::INT)) {
856 const TypeInt *r0 = t11->is_int();
857 const TypeInt *r1 = t12->is_int();
858 jlong lo_r0 = r0->_lo;
859 jlong hi_r0 = r0->_hi;
860 jlong lo_r1 = r1->_lo;
861 jlong hi_r1 = r1->_hi;
862 if (in1_op == Op_SubI) {
863 jlong tmp = hi_r1;
864 hi_r1 = -lo_r1;
865 lo_r1 = -tmp;
866 // Note, for substructing [minint,x] type range
867 // long arithmetic provides correct overflow answer.
868 // The confusion come from the fact that in 32-bit
869 // -minint == minint but in 64-bit -minint == maxint+1.
870 }
871 jlong lo_long = lo_r0 + lo_r1;
872 jlong hi_long = hi_r0 + hi_r1;
873 int lo_tr1 = min_jint;
874 int hi_tr1 = (int)hi_long;
875 int lo_tr2 = (int)lo_long;
876 int hi_tr2 = max_jint;
877 bool underflow = lo_long != (jlong)lo_tr2;
878 bool overflow = hi_long != (jlong)hi_tr1;
879 // Use sub(t1, t2) when there is no overflow (one type range)
880 // or when both overflow and underflow (too complex).
881 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) {
882 // Overflow only on one boundary, compare 2 separate type ranges.
883 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
884 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w);
885 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w);
886 const TypeInt* cmp1 = sub(tr1, t2)->is_int();
887 const TypeInt* cmp2 = sub(tr2, t2)->is_int();
888 // Compute union, so that cmp handles all possible results from the two cases
889 const Type* t_cmp = cmp1->meet(cmp2);
890 // Pick narrowest type, based on overflow computation and on immediate inputs
891 return t_sub->filter(t_cmp);
892 }
893 }
894 }
895
896 return t_sub;
897 }
898
899 bool CmpUNode::is_index_range_check() const {
900 // Check for the "(X ModI Y) CmpU Y" shape
901 return (in(1)->Opcode() == Op_ModI &&
902 in(1)->in(2)->eqv_uncast(in(2)));
903 }
904
905 //------------------------------Idealize---------------------------------------
906 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
907 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) {
908 switch (in(1)->Opcode()) {
909 case Op_CmpU3: // Collapse a CmpU3/CmpI into a CmpU
910 return new CmpUNode(in(1)->in(1),in(1)->in(2));
911 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL
912 return new CmpLNode(in(1)->in(1),in(1)->in(2));
913 case Op_CmpUL3: // Collapse a CmpUL3/CmpI into a CmpUL
914 return new CmpULNode(in(1)->in(1),in(1)->in(2));
915 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF
916 return new CmpFNode(in(1)->in(1),in(1)->in(2));
917 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD
918 return new CmpDNode(in(1)->in(1),in(1)->in(2));
919 //case Op_SubI:
920 // If (x - y) cannot overflow, then ((x - y) <?> 0)
921 // can be turned into (x <?> y).
922 // This is handled (with more general cases) by Ideal_sub_algebra.
923 }
924 }
925 return nullptr; // No change
926 }
927
928 //------------------------------Ideal------------------------------------------
929 Node* CmpLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
930 // Optimize expressions like
931 // CmpL(OrL(CastP2X(..), CastP2X(..)), 0L)
932 // that are used by acmp to implement a "both operands are null" check.
933 // See also the corresponding code in CmpPNode::Ideal.
934 if (can_reshape && in(1)->Opcode() == Op_OrL &&
935 in(2)->bottom_type()->is_zero_type()) {
936 for (int i = 1; i <= 2; ++i) {
937 Node* orIn = in(1)->in(i);
938 if (orIn->Opcode() == Op_CastP2X) {
939 Node* castIn = orIn->in(1);
940 if (castIn->is_InlineType()) {
941 // Replace the CastP2X by the null marker
942 InlineTypeNode* vt = castIn->as_InlineType();
943 Node* nm = phase->transform(new ConvI2LNode(vt->get_null_marker()));
944 phase->is_IterGVN()->replace_input_of(in(1), i, nm);
945 return this;
946 } else if (!phase->type(castIn)->maybe_null()) {
947 // Never null. Replace the CastP2X by constant 1L.
948 phase->is_IterGVN()->replace_input_of(in(1), i, phase->longcon(1));
949 return this;
950 }
951 }
952 }
953 }
954 const TypeLong *t2 = phase->type(in(2))->isa_long();
955 if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) {
956 const jlong con = t2->get_con();
957 if (con >= min_jint && con <= max_jint) {
958 return new CmpINode(in(1)->in(1), phase->intcon((jint)con));
959 }
960 }
961 return nullptr;
962 }
963
964 //=============================================================================
965 // Simplify a CmpL (compare 2 longs ) node, based on local information.
966 // If both inputs are constants, compare them.
967 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const {
968 const TypeLong *r0 = t1->is_long(); // Handy access
969 const TypeLong *r1 = t2->is_long();
970
971 if( r0->_hi < r1->_lo ) // Range is always low?
972 return TypeInt::CC_LT;
973 else if( r0->_lo > r1->_hi ) // Range is always high?
974 return TypeInt::CC_GT;
975
976 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
977 assert(r0->get_con() == r1->get_con(), "must be equal");
978 return TypeInt::CC_EQ; // Equal results.
979 } else if( r0->_hi == r1->_lo ) // Range is never high?
980 return TypeInt::CC_LE;
981 else if( r0->_lo == r1->_hi ) // Range is never low?
982 return TypeInt::CC_GE;
983
984 const Type* joined = r0->join(r1);
985 if (joined == Type::TOP) {
986 return TypeInt::CC_NE;
987 }
988
989 return TypeInt::CC; // else use worst case results
990 }
991
992
993 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information.
994 // If both inputs are constants, compare them.
995 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const {
996 assert(!t1->isa_ptr(), "obsolete usage of CmpUL");
997
998 // comparing two unsigned longs
999 const TypeLong* r0 = t1->is_long(); // Handy access
1000 const TypeLong* r1 = t2->is_long();
1001
1002 // Current installed version
1003 // Compare ranges for non-overlap
1004 julong lo0 = r0->_lo;
1005 julong hi0 = r0->_hi;
1006 julong lo1 = r1->_lo;
1007 julong hi1 = r1->_hi;
1008
1009 // If either one has both negative and positive values,
1010 // it therefore contains both 0 and -1, and since [0..-1] is the
1011 // full unsigned range, the type must act as an unsigned bottom.
1012 bool bot0 = ((jlong)(lo0 ^ hi0) < 0);
1013 bool bot1 = ((jlong)(lo1 ^ hi1) < 0);
1014
1015 if (bot0 || bot1) {
1016 // All unsigned values are LE -1 and GE 0.
1017 if (lo0 == 0 && hi0 == 0) {
1018 return TypeInt::CC_LE; // 0 <= bot
1019 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) {
1020 return TypeInt::CC_GE; // -1 >= bot
1021 } else if (lo1 == 0 && hi1 == 0) {
1022 return TypeInt::CC_GE; // bot >= 0
1023 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) {
1024 return TypeInt::CC_LE; // bot <= -1
1025 }
1026 } else {
1027 // We can use ranges of the form [lo..hi] if signs are the same.
1028 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
1029 // results are reversed, '-' > '+' for unsigned compare
1030 if (hi0 < lo1) {
1031 return TypeInt::CC_LT; // smaller
1032 } else if (lo0 > hi1) {
1033 return TypeInt::CC_GT; // greater
1034 } else if (hi0 == lo1 && lo0 == hi1) {
1035 return TypeInt::CC_EQ; // Equal results
1036 } else if (lo0 >= hi1) {
1037 return TypeInt::CC_GE;
1038 } else if (hi0 <= lo1) {
1039 return TypeInt::CC_LE;
1040 }
1041 }
1042
1043 const Type* joined = r0->join(r1);
1044 if (joined == Type::TOP) {
1045 return TypeInt::CC_NE;
1046 }
1047
1048 return TypeInt::CC; // else use worst case results
1049 }
1050
1051 //=============================================================================
1052 //------------------------------sub--------------------------------------------
1053 // Simplify an CmpP (compare 2 pointers) node, based on local information.
1054 // If both inputs are constants, compare them.
1055 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const {
1056 const TypePtr *r0 = t1->is_ptr(); // Handy access
1057 const TypePtr *r1 = t2->is_ptr();
1058
1059 // Undefined inputs makes for an undefined result
1060 if( TypePtr::above_centerline(r0->_ptr) ||
1061 TypePtr::above_centerline(r1->_ptr) )
1062 return Type::TOP;
1063
1064 if (r0 == r1 && r0->singleton()) {
1065 // Equal pointer constants (klasses, nulls, etc.)
1066 return TypeInt::CC_EQ;
1067 }
1068
1069 // See if it is 2 unrelated classes.
1070 const TypeOopPtr* p0 = r0->isa_oopptr();
1071 const TypeOopPtr* p1 = r1->isa_oopptr();
1072 const TypeKlassPtr* k0 = r0->isa_klassptr();
1073 const TypeKlassPtr* k1 = r1->isa_klassptr();
1074 if ((p0 && p1) || (k0 && k1)) {
1075 if (p0 && p1) {
1076 Node* in1 = in(1)->uncast();
1077 Node* in2 = in(2)->uncast();
1078 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1);
1079 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2);
1080 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, nullptr)) {
1081 return TypeInt::CC_GT; // different pointers
1082 }
1083 }
1084 bool xklass0 = p0 ? p0->klass_is_exact() : k0->klass_is_exact();
1085 bool xklass1 = p1 ? p1->klass_is_exact() : k1->klass_is_exact();
1086 bool unrelated_classes = false;
1087
1088 if ((p0 && p0->is_same_java_type_as(p1)) ||
1089 (k0 && k0->is_same_java_type_as(k1))) {
1090 } else if ((p0 && !p1->maybe_java_subtype_of(p0) && !p0->maybe_java_subtype_of(p1)) ||
1091 (k0 && !k1->maybe_java_subtype_of(k0) && !k0->maybe_java_subtype_of(k1))) {
1092 unrelated_classes = true;
1093 } else if ((p0 && !p1->maybe_java_subtype_of(p0)) ||
1094 (k0 && !k1->maybe_java_subtype_of(k0))) {
1095 unrelated_classes = xklass1;
1096 } else if ((p0 && !p0->maybe_java_subtype_of(p1)) ||
1097 (k0 && !k0->maybe_java_subtype_of(k1))) {
1098 unrelated_classes = xklass0;
1099 }
1100 if (!unrelated_classes) {
1101 // Handle inline type arrays
1102 if ((r0->is_flat_in_array() && r1->is_not_flat_in_array()) ||
1103 (r1->is_flat_in_array() && r0->is_not_flat_in_array())) {
1104 // One type is in flat arrays but the other type is not. Must be unrelated.
1105 unrelated_classes = true;
1106 } else if ((r0->is_not_flat() && r1->is_flat()) ||
1107 (r1->is_not_flat() && r0->is_flat())) {
1108 // One type is a non-flat array and the other type is a flat array. Must be unrelated.
1109 unrelated_classes = true;
1110 } else if ((r0->is_not_null_free() && r1->is_null_free()) ||
1111 (r1->is_not_null_free() && r0->is_null_free())) {
1112 // One type is a nullable array and the other type is a null-free array. Must be unrelated.
1113 unrelated_classes = true;
1114 }
1115 }
1116 if (unrelated_classes) {
1117 // The oops classes are known to be unrelated. If the joined PTRs of
1118 // two oops is not Null and not Bottom, then we are sure that one
1119 // of the two oops is non-null, and the comparison will always fail.
1120 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
1121 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
1122 return TypeInt::CC_GT;
1123 }
1124 }
1125 }
1126
1127 // Known constants can be compared exactly
1128 // Null can be distinguished from any NotNull pointers
1129 // Unknown inputs makes an unknown result
1130 if( r0->singleton() ) {
1131 intptr_t bits0 = r0->get_con();
1132 if( r1->singleton() )
1133 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
1134 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1135 } else if( r1->singleton() ) {
1136 intptr_t bits1 = r1->get_con();
1137 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1138 } else
1139 return TypeInt::CC;
1140 }
1141
1142 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n, bool& might_be_an_array) {
1143 // Return the klass node for (indirect load from OopHandle)
1144 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
1145 // or null if not matching.
1146 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1147 n = bs->step_over_gc_barrier(n);
1148
1149 if (n->Opcode() != Op_LoadP) return nullptr;
1150
1151 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1152 if (!tp || tp->instance_klass() != phase->C->env()->Class_klass()) return nullptr;
1153
1154 Node* adr = n->in(MemNode::Address);
1155 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier.
1156 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return nullptr;
1157 adr = adr->in(MemNode::Address);
1158
1159 intptr_t off = 0;
1160 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off);
1161 if (k == nullptr) return nullptr;
1162 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr();
1163 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return nullptr;
1164 might_be_an_array |= tkp->isa_aryklassptr() || tkp->is_instklassptr()->might_be_an_array();
1165
1166 // We've found the klass node of a Java mirror load.
1167 return k;
1168 }
1169
1170 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n, bool& might_be_an_array) {
1171 // for ConP(Foo.class) return ConP(Foo.klass)
1172 // otherwise return null
1173 if (!n->is_Con()) return nullptr;
1174
1175 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1176 if (!tp) return nullptr;
1177
1178 ciType* mirror_type = tp->java_mirror_type();
1179 // TypeInstPtr::java_mirror_type() returns non-null for compile-
1180 // time Class constants only.
1181 if (!mirror_type) return nullptr;
1182
1183 // x.getClass() == int.class can never be true (for all primitive types)
1184 // Return a ConP(null) node for this case.
1185 if (mirror_type->is_classless()) {
1186 return phase->makecon(TypePtr::NULL_PTR);
1187 }
1188
1189 // return the ConP(Foo.klass)
1190 ciKlass* mirror_klass = mirror_type->as_klass();
1191
1192 if (mirror_klass->is_array_klass() && !mirror_klass->is_type_array_klass()) {
1193 if (!mirror_klass->can_be_inline_array_klass()) {
1194 // Special case for non-value arrays: They only have one (default) refined class, use it
1195 ciArrayKlass* refined_mirror_klass = ciObjArrayKlass::make(mirror_klass->as_array_klass()->element_klass(), true);
1196 return phase->makecon(TypeAryKlassPtr::make(refined_mirror_klass, Type::trust_interfaces));
1197 }
1198 might_be_an_array |= true;
1199 }
1200
1201 return phase->makecon(TypeKlassPtr::make(mirror_klass, Type::trust_interfaces));
1202 }
1203
1204 //------------------------------Ideal------------------------------------------
1205 // Normalize comparisons between Java mirror loads to compare the klass instead.
1206 //
1207 // Also check for the case of comparing an unknown klass loaded from the primary
1208 // super-type array vs a known klass with no subtypes. This amounts to
1209 // checking to see an unknown klass subtypes a known klass with no subtypes;
1210 // this only happens on an exact match. We can shorten this test by 1 load.
1211 Node* CmpPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1212 // TODO 8284443 in(1) could be cast?
1213 if (in(1)->is_InlineType() && phase->type(in(2))->is_zero_type()) {
1214 // Null checking a scalarized but nullable inline type. Check the null marker
1215 // input instead of the oop input to avoid keeping buffer allocations alive.
1216 return new CmpINode(in(1)->as_InlineType()->get_null_marker(), phase->intcon(0));
1217 }
1218 if (in(1)->is_InlineType() || in(2)->is_InlineType()) {
1219 // In C2 IR, CmpP on value objects is a pointer comparison, not a value comparison.
1220 // For non-null operands it cannot reliably be true, since their buffer oops are not
1221 // guaranteed to be identical. Therefore, the comparison can only be true when both
1222 // operands are null. Convert expressions like this to a "both operands are null" check:
1223 // CmpL(OrL(CastP2X(..), CastP2X(..)), 0L)
1224 // CmpLNode::Ideal might optimize this further to avoid keeping buffer allocations alive.
1225 Node* input[2];
1226 for (int i = 1; i <= 2; ++i) {
1227 if (in(i)->is_InlineType()) {
1228 input[i-1] = phase->transform(new ConvI2LNode(in(i)->as_InlineType()->get_null_marker()));
1229 } else {
1230 input[i-1] = phase->transform(new CastP2XNode(nullptr, in(i)));
1231 }
1232 }
1233 Node* orL = phase->transform(new OrXNode(input[0], input[1]));
1234 return new CmpXNode(orL, phase->MakeConX(0));
1235 }
1236
1237 // Normalize comparisons between Java mirrors into comparisons of the low-
1238 // level klass, where a dependent load could be shortened.
1239 //
1240 // The new pattern has a nice effect of matching the same pattern used in the
1241 // fast path of instanceof/checkcast/Class.isInstance(), which allows
1242 // redundant exact type check be optimized away by GVN.
1243 // For example, in
1244 // if (x.getClass() == Foo.class) {
1245 // Foo foo = (Foo) x;
1246 // // ... use a ...
1247 // }
1248 // a CmpPNode could be shared between if_acmpne and checkcast
1249 {
1250 bool might_be_an_array1 = false;
1251 bool might_be_an_array2 = false;
1252 Node* k1 = isa_java_mirror_load(phase, in(1), might_be_an_array1);
1253 Node* k2 = isa_java_mirror_load(phase, in(2), might_be_an_array2);
1254 Node* conk2 = isa_const_java_mirror(phase, in(2), might_be_an_array2);
1255 if (might_be_an_array1 && might_be_an_array2) {
1256 // Don't optimize if both sides might be an array because arrays with
1257 // the same Java mirror can have different refined array klasses.
1258 k1 = k2 = nullptr;
1259 }
1260
1261 if (k1 && (k2 || conk2)) {
1262 Node* lhs = k1;
1263 Node* rhs = (k2 != nullptr) ? k2 : conk2;
1264 set_req_X(1, lhs, phase);
1265 set_req_X(2, rhs, phase);
1266 return this;
1267 }
1268 }
1269
1270 // Constant pointer on right?
1271 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
1272 if (t2 == nullptr || !t2->klass_is_exact())
1273 return nullptr;
1274 // Get the constant klass we are comparing to.
1275 ciKlass* superklass = t2->exact_klass();
1276
1277 // Now check for LoadKlass on left.
1278 Node* ldk1 = in(1);
1279 if (ldk1->is_DecodeNKlass()) {
1280 ldk1 = ldk1->in(1);
1281 if (ldk1->Opcode() != Op_LoadNKlass )
1282 return nullptr;
1283 } else if (ldk1->Opcode() != Op_LoadKlass )
1284 return nullptr;
1285 // Take apart the address of the LoadKlass:
1286 Node* adr1 = ldk1->in(MemNode::Address);
1287 intptr_t con2 = 0;
1288 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
1289 if (ldk2 == nullptr)
1290 return nullptr;
1291 if (con2 == oopDesc::klass_offset_in_bytes()) {
1292 // We are inspecting an object's concrete class.
1293 // Short-circuit the check if the query is abstract.
1294 if (superklass->is_interface() ||
1295 superklass->is_abstract()) {
1296 // Make it come out always false:
1297 this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
1298 return this;
1299 }
1300 }
1301
1302 // Check for a LoadKlass from primary supertype array.
1303 // Any nested loadklass from loadklass+con must be from the p.s. array.
1304 if (ldk2->is_DecodeNKlass()) {
1305 // Keep ldk2 as DecodeN since it could be used in CmpP below.
1306 if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
1307 return nullptr;
1308 } else if (ldk2->Opcode() != Op_LoadKlass)
1309 return nullptr;
1310
1311 // Verify that we understand the situation
1312 if (con2 != (intptr_t) superklass->super_check_offset())
1313 return nullptr; // Might be element-klass loading from array klass
1314
1315 // If 'superklass' has no subklasses and is not an interface, then we are
1316 // assured that the only input which will pass the type check is
1317 // 'superklass' itself.
1318 //
1319 // We could be more liberal here, and allow the optimization on interfaces
1320 // which have a single implementor. This would require us to increase the
1321 // expressiveness of the add_dependency() mechanism.
1322 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now.
1323
1324 // Object arrays must have their base element have no subtypes
1325 while (superklass->is_obj_array_klass()) {
1326 ciType* elem = superklass->as_obj_array_klass()->element_type();
1327 superklass = elem->as_klass();
1328 }
1329 if (superklass->is_instance_klass()) {
1330 ciInstanceKlass* ik = superklass->as_instance_klass();
1331 if (ik->has_subklass() || ik->is_interface()) return nullptr;
1332 // Add a dependency if there is a chance that a subclass will be added later.
1333 if (!ik->is_final()) {
1334 phase->C->dependencies()->assert_leaf_type(ik);
1335 }
1336 }
1337
1338 // Do not fold the subtype check to an array klass pointer comparison for
1339 // value class arrays because they can have multiple refined array klasses.
1340 superklass = t2->exact_klass();
1341 assert(!superklass->is_flat_array_klass(), "Unexpected flat array klass");
1342 if (superklass->is_obj_array_klass()) {
1343 if (superklass->as_array_klass()->element_klass()->is_inlinetype() && !superklass->as_array_klass()->is_refined()) {
1344 return nullptr;
1345 } else {
1346 // Special case for non-value arrays: They only have one (default) refined class, use it
1347 set_req_X(2, phase->makecon(t2->is_aryklassptr()->cast_to_refined_array_klass_ptr()), phase);
1348 }
1349 }
1350
1351 // Bypass the dependent load, and compare directly
1352 this->set_req_X(1, ldk2, phase);
1353
1354 return this;
1355 }
1356
1357 //=============================================================================
1358 //------------------------------sub--------------------------------------------
1359 // Simplify an CmpN (compare 2 pointers) node, based on local information.
1360 // If both inputs are constants, compare them.
1361 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
1362 ShouldNotReachHere();
1363 return bottom_type();
1364 }
1365
1366 //------------------------------Ideal------------------------------------------
1367 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1368 return nullptr;
1369 }
1370
1371 //=============================================================================
1372 //------------------------------Value------------------------------------------
1373 // Simplify an CmpF (compare 2 floats ) node, based on local information.
1374 // If both inputs are constants, compare them.
1375 const Type* CmpFNode::Value(PhaseGVN* phase) const {
1376 const Node* in1 = in(1);
1377 const Node* in2 = in(2);
1378 // Either input is TOP ==> the result is TOP
1379 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1380 if( t1 == Type::TOP ) return Type::TOP;
1381 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1382 if( t2 == Type::TOP ) return Type::TOP;
1383
1384 // Not constants? Don't know squat - even if they are the same
1385 // value! If they are NaN's they compare to LT instead of EQ.
1386 const TypeF *tf1 = t1->isa_float_constant();
1387 const TypeF *tf2 = t2->isa_float_constant();
1388 if( !tf1 || !tf2 ) return TypeInt::CC;
1389
1390 // This implements the Java bytecode fcmpl, so unordered returns -1.
1391 if( tf1->is_nan() || tf2->is_nan() )
1392 return TypeInt::CC_LT;
1393
1394 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
1395 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
1396 assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
1397 return TypeInt::CC_EQ;
1398 }
1399
1400
1401 //=============================================================================
1402 //------------------------------Value------------------------------------------
1403 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
1404 // If both inputs are constants, compare them.
1405 const Type* CmpDNode::Value(PhaseGVN* phase) const {
1406 const Node* in1 = in(1);
1407 const Node* in2 = in(2);
1408 // Either input is TOP ==> the result is TOP
1409 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1410 if( t1 == Type::TOP ) return Type::TOP;
1411 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1412 if( t2 == Type::TOP ) return Type::TOP;
1413
1414 // Not constants? Don't know squat - even if they are the same
1415 // value! If they are NaN's they compare to LT instead of EQ.
1416 const TypeD *td1 = t1->isa_double_constant();
1417 const TypeD *td2 = t2->isa_double_constant();
1418 if( !td1 || !td2 ) return TypeInt::CC;
1419
1420 // This implements the Java bytecode dcmpl, so unordered returns -1.
1421 if( td1->is_nan() || td2->is_nan() )
1422 return TypeInt::CC_LT;
1423
1424 if( td1->_d < td2->_d ) return TypeInt::CC_LT;
1425 if( td1->_d > td2->_d ) return TypeInt::CC_GT;
1426 assert( td1->_d == td2->_d, "do not understand FP behavior" );
1427 return TypeInt::CC_EQ;
1428 }
1429
1430 //------------------------------Ideal------------------------------------------
1431 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
1432 // Check if we can change this to a CmpF and remove a ConvD2F operation.
1433 // Change (CMPD (F2D (float)) (ConD value))
1434 // To (CMPF (float) (ConF value))
1435 // Valid when 'value' does not lose precision as a float.
1436 // Benefits: eliminates conversion, does not require 24-bit mode
1437
1438 // NaNs prevent commuting operands. This transform works regardless of the
1439 // order of ConD and ConvF2D inputs by preserving the original order.
1440 int idx_f2d = 1; // ConvF2D on left side?
1441 if( in(idx_f2d)->Opcode() != Op_ConvF2D )
1442 idx_f2d = 2; // No, swap to check for reversed args
1443 int idx_con = 3-idx_f2d; // Check for the constant on other input
1444
1445 if( ConvertCmpD2CmpF &&
1446 in(idx_f2d)->Opcode() == Op_ConvF2D &&
1447 in(idx_con)->Opcode() == Op_ConD ) {
1448 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
1449 double t2_value_as_double = t2->_d;
1450 float t2_value_as_float = (float)t2_value_as_double;
1451 if( t2_value_as_double == (double)t2_value_as_float ) {
1452 // Test value can be represented as a float
1453 // Eliminate the conversion to double and create new comparison
1454 Node *new_in1 = in(idx_f2d)->in(1);
1455 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
1456 if( idx_f2d != 1 ) { // Must flip args to match original order
1457 Node *tmp = new_in1;
1458 new_in1 = new_in2;
1459 new_in2 = tmp;
1460 }
1461 CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
1462 ? new CmpF3Node( new_in1, new_in2 )
1463 : new CmpFNode ( new_in1, new_in2 ) ;
1464 return new_cmp; // Changed to CmpFNode
1465 }
1466 // Testing value required the precision of a double
1467 }
1468 return nullptr; // No change
1469 }
1470
1471 //=============================================================================
1472 //------------------------------Value------------------------------------------
1473 const Type* FlatArrayCheckNode::Value(PhaseGVN* phase) const {
1474 bool all_not_flat = true;
1475 for (uint i = ArrayOrKlass; i < req(); ++i) {
1476 const Type* t = phase->type(in(i));
1477 if (t == Type::TOP) {
1478 return Type::TOP;
1479 }
1480 if (t->is_ptr()->is_flat()) {
1481 // One of the input arrays is flat, check always passes
1482 return TypeInt::CC_EQ;
1483 } else if (!t->is_ptr()->is_not_flat()) {
1484 // One of the input arrays might be flat
1485 all_not_flat = false;
1486 }
1487 }
1488 if (all_not_flat) {
1489 // None of the input arrays can be flat, check always fails
1490 return TypeInt::CC_GT;
1491 }
1492 return TypeInt::CC;
1493 }
1494
1495 //------------------------------Ideal------------------------------------------
1496 Node* FlatArrayCheckNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1497 bool changed = false;
1498 // Remove inputs that are known to be non-flat
1499 for (uint i = ArrayOrKlass; i < req(); ++i) {
1500 const Type* t = phase->type(in(i));
1501 if (t->isa_ptr() && t->is_ptr()->is_not_flat()) {
1502 del_req(i--);
1503 changed = true;
1504 }
1505 }
1506 return changed ? this : nullptr;
1507 }
1508
1509 //=============================================================================
1510 //------------------------------cc2logical-------------------------------------
1511 // Convert a condition code type to a logical type
1512 const Type *BoolTest::cc2logical( const Type *CC ) const {
1513 if( CC == Type::TOP ) return Type::TOP;
1514 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
1515 const TypeInt *ti = CC->is_int();
1516 if( ti->is_con() ) { // Only 1 kind of condition codes set?
1517 // Match low order 2 bits
1518 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
1519 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result
1520 return TypeInt::make(tmp); // Boolean result
1521 }
1522
1523 if( CC == TypeInt::CC_GE ) {
1524 if( _test == ge ) return TypeInt::ONE;
1525 if( _test == lt ) return TypeInt::ZERO;
1526 }
1527 if( CC == TypeInt::CC_LE ) {
1528 if( _test == le ) return TypeInt::ONE;
1529 if( _test == gt ) return TypeInt::ZERO;
1530 }
1531 if( CC == TypeInt::CC_NE ) {
1532 if( _test == ne ) return TypeInt::ONE;
1533 if( _test == eq ) return TypeInt::ZERO;
1534 }
1535
1536 return TypeInt::BOOL;
1537 }
1538
1539 BoolTest::mask BoolTest::unsigned_mask(BoolTest::mask btm) {
1540 switch(btm) {
1541 case eq:
1542 case ne:
1543 return btm;
1544 case lt:
1545 case le:
1546 case gt:
1547 case ge:
1548 return mask(btm | unsigned_compare);
1549 default:
1550 ShouldNotReachHere();
1551 }
1552 }
1553
1554 //------------------------------dump_spec-------------------------------------
1555 // Print special per-node info
1556 void BoolTest::dump_on(outputStream *st) const {
1557 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"};
1558 st->print("%s", msg[_test]);
1559 }
1560
1561 // Returns the logical AND of two tests (or 'never' if both tests can never be true).
1562 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'.
1563 BoolTest::mask BoolTest::merge(BoolTest other) const {
1564 const mask res[illegal+1][illegal+1] = {
1565 // eq, gt, of, lt, ne, le, nof, ge, never, illegal
1566 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq
1567 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt
1568 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of
1569 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt
1570 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne
1571 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le
1572 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof
1573 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge
1574 {never, never, never, never, never, never, never, never, never, illegal}, // never
1575 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal
1576 return res[_test][other._test];
1577 }
1578
1579 //=============================================================================
1580 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
1581 uint BoolNode::size_of() const { return sizeof(BoolNode); }
1582
1583 //------------------------------operator==-------------------------------------
1584 bool BoolNode::cmp( const Node &n ) const {
1585 const BoolNode *b = (const BoolNode *)&n; // Cast up
1586 return (_test._test == b->_test._test);
1587 }
1588
1589 //-------------------------------make_predicate--------------------------------
1590 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1591 if (test_value->is_Con()) return test_value;
1592 if (test_value->is_Bool()) return test_value;
1593 if (test_value->is_CMove() &&
1594 test_value->in(CMoveNode::Condition)->is_Bool()) {
1595 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool();
1596 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1597 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1598 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1599 return bol;
1600 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1601 return phase->transform( bol->negate(phase) );
1602 }
1603 // Else fall through. The CMove gets in the way of the test.
1604 // It should be the case that make_predicate(bol->as_int_value()) == bol.
1605 }
1606 Node* cmp = new CmpINode(test_value, phase->intcon(0));
1607 cmp = phase->transform(cmp);
1608 Node* bol = new BoolNode(cmp, BoolTest::ne);
1609 return phase->transform(bol);
1610 }
1611
1612 //--------------------------------as_int_value---------------------------------
1613 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1614 // Inverse to make_predicate. The CMove probably boils down to a Conv2B.
1615 Node* cmov = CMoveNode::make(this, phase->intcon(0), phase->intcon(1), TypeInt::BOOL);
1616 return phase->transform(cmov);
1617 }
1618
1619 //----------------------------------negate-------------------------------------
1620 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1621 return new BoolNode(in(1), _test.negate());
1622 }
1623
1624 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub
1625 // overflows and we can prove that C is not in the two resulting ranges.
1626 // This optimization is similar to the one performed by CmpUNode::Value().
1627 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op,
1628 int cmp1_op, const TypeInt* cmp2_type) {
1629 // Only optimize eq/ne integer comparison of add/sub
1630 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1631 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) {
1632 // Skip cases were inputs of add/sub are not integers or of bottom type
1633 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int();
1634 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int();
1635 if ((r0 != nullptr) && (r0 != TypeInt::INT) &&
1636 (r1 != nullptr) && (r1 != TypeInt::INT) &&
1637 (cmp2_type != TypeInt::INT)) {
1638 // Compute exact (long) type range of add/sub result
1639 jlong lo_long = r0->_lo;
1640 jlong hi_long = r0->_hi;
1641 if (cmp1_op == Op_AddI) {
1642 lo_long += r1->_lo;
1643 hi_long += r1->_hi;
1644 } else {
1645 lo_long -= r1->_hi;
1646 hi_long -= r1->_lo;
1647 }
1648 // Check for over-/underflow by casting to integer
1649 int lo_int = (int)lo_long;
1650 int hi_int = (int)hi_long;
1651 bool underflow = lo_long != (jlong)lo_int;
1652 bool overflow = hi_long != (jlong)hi_int;
1653 if ((underflow != overflow) && (hi_int < lo_int)) {
1654 // Overflow on one boundary, compute resulting type ranges:
1655 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT]
1656 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
1657 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w);
1658 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w);
1659 // Compare second input of cmp to both type ranges
1660 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type);
1661 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type);
1662 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) {
1663 // The result of the add/sub will never equal cmp2. Replace BoolNode
1664 // by false (0) if it tests for equality and by true (1) otherwise.
1665 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1);
1666 }
1667 }
1668 }
1669 }
1670 return nullptr;
1671 }
1672
1673 static bool is_counted_loop_cmp(Node *cmp) {
1674 Node *n = cmp->in(1)->in(1);
1675 return n != nullptr &&
1676 n->is_Phi() &&
1677 n->in(0) != nullptr &&
1678 n->in(0)->is_CountedLoop() &&
1679 n->in(0)->as_CountedLoop()->phi() == n;
1680 }
1681
1682 //------------------------------Ideal------------------------------------------
1683 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1684 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1685 // This moves the constant to the right. Helps value-numbering.
1686 Node *cmp = in(1);
1687 if( !cmp->is_Sub() ) return nullptr;
1688 int cop = cmp->Opcode();
1689 if( cop == Op_FastLock || cop == Op_FastUnlock ||
1690 cmp->is_SubTypeCheck() || cop == Op_VectorTest ) {
1691 return nullptr;
1692 }
1693 Node *cmp1 = cmp->in(1);
1694 Node *cmp2 = cmp->in(2);
1695 if( !cmp1 ) return nullptr;
1696
1697 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) {
1698 return nullptr;
1699 }
1700
1701 const int cmp1_op = cmp1->Opcode();
1702 const int cmp2_op = cmp2->Opcode();
1703
1704 // Constant on left?
1705 Node *con = cmp1;
1706 // Move constants to the right of compare's to canonicalize.
1707 // Do not muck with Opaque1 nodes, as this indicates a loop
1708 // guard that cannot change shape.
1709 if (con->is_Con() && !cmp2->is_Con() && cmp2_op != Op_OpaqueZeroTripGuard &&
1710 // Because of NaN's, CmpD and CmpF are not commutative
1711 cop != Op_CmpD && cop != Op_CmpF &&
1712 // Protect against swapping inputs to a compare when it is used by a
1713 // counted loop exit, which requires maintaining the loop-limit as in(2)
1714 !is_counted_loop_exit_test() ) {
1715 // Ok, commute the constant to the right of the cmp node.
1716 // Clone the Node, getting a new Node of the same class
1717 cmp = cmp->clone();
1718 // Swap inputs to the clone
1719 cmp->swap_edges(1, 2);
1720 cmp = phase->transform( cmp );
1721 return new BoolNode( cmp, _test.commute() );
1722 }
1723
1724 // Change "bool eq/ne (cmp (cmove (bool tst (cmp2)) 1 0) 0)" into "bool tst/~tst (cmp2)"
1725 if (cop == Op_CmpI &&
1726 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1727 cmp1_op == Op_CMoveI && cmp2->find_int_con(1) == 0) {
1728 // 0 should be on the true branch
1729 if (cmp1->in(CMoveNode::Condition)->is_Bool() &&
1730 cmp1->in(CMoveNode::IfTrue)->find_int_con(1) == 0 &&
1731 cmp1->in(CMoveNode::IfFalse)->find_int_con(0) != 0) {
1732 BoolNode* target = cmp1->in(CMoveNode::Condition)->as_Bool();
1733 return new BoolNode(target->in(1),
1734 (_test._test == BoolTest::eq) ? target->_test._test :
1735 target->_test.negate());
1736 }
1737 }
1738
1739 // Change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1740 if (cop == Op_CmpI &&
1741 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1742 cmp1_op == Op_AndI && cmp2_op == Op_ConI &&
1743 cmp1->in(2)->Opcode() == Op_ConI) {
1744 const TypeInt *t12 = phase->type(cmp2)->isa_int();
1745 const TypeInt *t112 = phase->type(cmp1->in(2))->isa_int();
1746 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1747 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1748 Node *ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1749 return new BoolNode(ncmp, _test.negate());
1750 }
1751 }
1752
1753 // Same for long type: change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1754 if (cop == Op_CmpL &&
1755 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1756 cmp1_op == Op_AndL && cmp2_op == Op_ConL &&
1757 cmp1->in(2)->Opcode() == Op_ConL) {
1758 const TypeLong *t12 = phase->type(cmp2)->isa_long();
1759 const TypeLong *t112 = phase->type(cmp1->in(2))->isa_long();
1760 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1761 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1762 Node *ncmp = phase->transform(new CmpLNode(cmp1, phase->longcon(0)));
1763 return new BoolNode(ncmp, _test.negate());
1764 }
1765 }
1766
1767 // Change "cmp (add X min_jint) (add Y min_jint)" into "cmpu X Y"
1768 // and "cmp (add X min_jint) c" into "cmpu X (c + min_jint)"
1769 if (cop == Op_CmpI &&
1770 cmp1_op == Op_AddI &&
1771 phase->type(cmp1->in(2)) == TypeInt::MIN &&
1772 !is_cloop_condition(this)) {
1773 if (cmp2_op == Op_ConI) {
1774 Node* ncmp2 = phase->intcon(java_add(cmp2->get_int(), min_jint));
1775 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), ncmp2));
1776 return new BoolNode(ncmp, _test._test);
1777 } else if (cmp2_op == Op_AddI &&
1778 phase->type(cmp2->in(2)) == TypeInt::MIN &&
1779 !is_cloop_condition(this)) {
1780 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), cmp2->in(1)));
1781 return new BoolNode(ncmp, _test._test);
1782 }
1783 }
1784
1785 // Change "cmp (add X min_jlong) (add Y min_jlong)" into "cmpu X Y"
1786 // and "cmp (add X min_jlong) c" into "cmpu X (c + min_jlong)"
1787 if (cop == Op_CmpL &&
1788 cmp1_op == Op_AddL &&
1789 phase->type(cmp1->in(2)) == TypeLong::MIN &&
1790 !is_cloop_condition(this)) {
1791 if (cmp2_op == Op_ConL) {
1792 Node* ncmp2 = phase->longcon(java_add(cmp2->get_long(), min_jlong));
1793 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), ncmp2));
1794 return new BoolNode(ncmp, _test._test);
1795 } else if (cmp2_op == Op_AddL &&
1796 phase->type(cmp2->in(2)) == TypeLong::MIN &&
1797 !is_cloop_condition(this)) {
1798 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), cmp2->in(1)));
1799 return new BoolNode(ncmp, _test._test);
1800 }
1801 }
1802
1803 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1804 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the
1805 // test instead.
1806 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1807 if (cmp2_type == nullptr) return nullptr;
1808 Node* j_xor = cmp1;
1809 if( cmp2_type == TypeInt::ZERO &&
1810 cmp1_op == Op_XorI &&
1811 j_xor->in(1) != j_xor && // An xor of itself is dead
1812 phase->type( j_xor->in(1) ) == TypeInt::BOOL &&
1813 phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1814 (_test._test == BoolTest::eq ||
1815 _test._test == BoolTest::ne) ) {
1816 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2));
1817 return new BoolNode( ncmp, _test.negate() );
1818 }
1819
1820 // Transform: "((x & (m - 1)) <u m)" or "(((m - 1) & x) <u m)" into "(m >u 0)"
1821 // This is case [CMPU_MASK] which is further described at the method comment of BoolNode::Value_cmpu_and_mask().
1822 if (cop == Op_CmpU && _test._test == BoolTest::lt && cmp1_op == Op_AndI) {
1823 Node* m = cmp2; // RHS: m
1824 for (int add_idx = 1; add_idx <= 2; add_idx++) { // LHS: "(m + (-1)) & x" or "x & (m + (-1))"?
1825 Node* maybe_m_minus_1 = cmp1->in(add_idx);
1826 if (maybe_m_minus_1->Opcode() == Op_AddI &&
1827 maybe_m_minus_1->in(2)->find_int_con(0) == -1 &&
1828 maybe_m_minus_1->in(1) == m) {
1829 Node* m_cmpu_0 = phase->transform(new CmpUNode(m, phase->intcon(0)));
1830 return new BoolNode(m_cmpu_0, BoolTest::gt);
1831 }
1832 }
1833 }
1834
1835 // Change x u< 1 or x u<= 0 to x == 0
1836 // and x u> 0 or u>= 1 to x != 0
1837 if (cop == Op_CmpU &&
1838 cmp1_op != Op_LoadRange &&
1839 (((_test._test == BoolTest::lt || _test._test == BoolTest::ge) &&
1840 cmp2->find_int_con(-1) == 1) ||
1841 ((_test._test == BoolTest::le || _test._test == BoolTest::gt) &&
1842 cmp2->find_int_con(-1) == 0))) {
1843 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1844 return new BoolNode(ncmp, _test.is_less() ? BoolTest::eq : BoolTest::ne);
1845 }
1846
1847 // Change (arraylength <= 0) or (arraylength == 0)
1848 // into (arraylength u<= 0)
1849 // Also change (arraylength != 0) into (arraylength u> 0)
1850 // The latter version matches the code pattern generated for
1851 // array range checks, which will more likely be optimized later.
1852 if (cop == Op_CmpI &&
1853 cmp1_op == Op_LoadRange &&
1854 cmp2->find_int_con(-1) == 0) {
1855 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) {
1856 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1857 return new BoolNode(ncmp, BoolTest::le);
1858 } else if (_test._test == BoolTest::ne) {
1859 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1860 return new BoolNode(ncmp, BoolTest::gt);
1861 }
1862 }
1863
1864 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1865 // This is a standard idiom for branching on a boolean value.
1866 Node *c2b = cmp1;
1867 if( cmp2_type == TypeInt::ZERO &&
1868 cmp1_op == Op_Conv2B &&
1869 (_test._test == BoolTest::eq ||
1870 _test._test == BoolTest::ne) ) {
1871 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1872 ? (Node*)new CmpINode(c2b->in(1),cmp2)
1873 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1874 );
1875 return new BoolNode( ncmp, _test._test );
1876 }
1877
1878 // Comparing a SubI against a zero is equal to comparing the SubI
1879 // arguments directly. This only works for eq and ne comparisons
1880 // due to possible integer overflow.
1881 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1882 (cop == Op_CmpI) &&
1883 (cmp1_op == Op_SubI) &&
1884 ( cmp2_type == TypeInt::ZERO ) ) {
1885 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2)));
1886 return new BoolNode( ncmp, _test._test );
1887 }
1888
1889 // Same as above but with and AddI of a constant
1890 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1891 cop == Op_CmpI &&
1892 cmp1_op == Op_AddI &&
1893 cmp1->in(2) != nullptr &&
1894 phase->type(cmp1->in(2))->isa_int() &&
1895 phase->type(cmp1->in(2))->is_int()->is_con() &&
1896 cmp2_type == TypeInt::ZERO &&
1897 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape
1898 ) {
1899 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int();
1900 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi)));
1901 return new BoolNode( ncmp, _test._test );
1902 }
1903
1904 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)"
1905 // since zero check of conditional negation of an integer is equal to
1906 // zero check of the integer directly.
1907 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1908 (cop == Op_CmpI) &&
1909 (cmp2_type == TypeInt::ZERO) &&
1910 (cmp1_op == Op_Phi)) {
1911 // There should be a diamond phi with true path at index 1 or 2
1912 PhiNode *phi = cmp1->as_Phi();
1913 int idx_true = phi->is_diamond_phi();
1914 if (idx_true != 0) {
1915 // True input is in(idx_true) while false input is in(3 - idx_true)
1916 Node *tin = phi->in(idx_true);
1917 Node *fin = phi->in(3 - idx_true);
1918 if ((tin->Opcode() == Op_SubI) &&
1919 (phase->type(tin->in(1)) == TypeInt::ZERO) &&
1920 (tin->in(2) == fin)) {
1921 // Found conditional negation at true path, create a new CmpINode without that
1922 Node *ncmp = phase->transform(new CmpINode(fin, cmp2));
1923 return new BoolNode(ncmp, _test._test);
1924 }
1925 if ((fin->Opcode() == Op_SubI) &&
1926 (phase->type(fin->in(1)) == TypeInt::ZERO) &&
1927 (fin->in(2) == tin)) {
1928 // Found conditional negation at false path, create a new CmpINode without that
1929 Node *ncmp = phase->transform(new CmpINode(tin, cmp2));
1930 return new BoolNode(ncmp, _test._test);
1931 }
1932 }
1933 }
1934
1935 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the
1936 // most general case because negating 0x80000000 does nothing. Needed for
1937 // the CmpF3/SubI/CmpI idiom.
1938 if( cop == Op_CmpI &&
1939 cmp1_op == Op_SubI &&
1940 cmp2_type == TypeInt::ZERO &&
1941 phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1942 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1943 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2));
1944 return new BoolNode( ncmp, _test.commute() );
1945 }
1946
1947 // Try to optimize signed integer comparison
1948 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type);
1949
1950 // The transformation below is not valid for either signed or unsigned
1951 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1952 // This transformation can be resurrected when we are able to
1953 // make inferences about the range of values being subtracted from
1954 // (or added to) relative to the wraparound point.
1955 //
1956 // // Remove +/-1's if possible.
1957 // // "X <= Y-1" becomes "X < Y"
1958 // // "X+1 <= Y" becomes "X < Y"
1959 // // "X < Y+1" becomes "X <= Y"
1960 // // "X-1 < Y" becomes "X <= Y"
1961 // // Do not this to compares off of the counted-loop-end. These guys are
1962 // // checking the trip counter and they want to use the post-incremented
1963 // // counter. If they use the PRE-incremented counter, then the counter has
1964 // // to be incremented in a private block on a loop backedge.
1965 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1966 // return nullptr;
1967 // #ifndef PRODUCT
1968 // // Do not do this in a wash GVN pass during verification.
1969 // // Gets triggered by too many simple optimizations to be bothered with
1970 // // re-trying it again and again.
1971 // if( !phase->allow_progress() ) return nullptr;
1972 // #endif
1973 // // Not valid for unsigned compare because of corner cases in involving zero.
1974 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1975 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1976 // // "0 <=u Y" is always true).
1977 // if( cmp->Opcode() == Op_CmpU ) return nullptr;
1978 // int cmp2_op = cmp2->Opcode();
1979 // if( _test._test == BoolTest::le ) {
1980 // if( cmp1_op == Op_AddI &&
1981 // phase->type( cmp1->in(2) ) == TypeInt::ONE )
1982 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1983 // else if( cmp2_op == Op_AddI &&
1984 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1985 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1986 // } else if( _test._test == BoolTest::lt ) {
1987 // if( cmp1_op == Op_AddI &&
1988 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1989 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1990 // else if( cmp2_op == Op_AddI &&
1991 // phase->type( cmp2->in(2) ) == TypeInt::ONE )
1992 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1993 // }
1994 }
1995
1996 // We use the following Lemmas/insights for the following two transformations (1) and (2):
1997 // x & y <=u y, for any x and y (Lemma 1, masking always results in a smaller unsigned number)
1998 // y <u y + 1 is always true if y != -1 (Lemma 2, (uint)(-1 + 1) == (uint)(UINT_MAX + 1) which overflows)
1999 // y <u 0 is always false for any y (Lemma 3, 0 == UINT_MIN and nothing can be smaller than that)
2000 //
2001 // (1a) Always: Change ((x & m) <=u m ) or ((m & x) <=u m ) to always true (true by Lemma 1)
2002 // (1b) If m != -1: Change ((x & m) <u m + 1) or ((m & x) <u m + 1) to always true:
2003 // x & m <=u m is always true // (Lemma 1)
2004 // x & m <=u m <u m + 1 is always true // (Lemma 2: m <u m + 1, if m != -1)
2005 //
2006 // A counter example for (1b), if we allowed m == -1:
2007 // (x & m) <u m + 1
2008 // (x & -1) <u 0
2009 // x <u 0
2010 // which is false for any x (Lemma 3)
2011 //
2012 // (2) Change ((x & (m - 1)) <u m) or (((m - 1) & x) <u m) to (m >u 0)
2013 // This is the off-by-one variant of the above.
2014 //
2015 // We now prove that this replacement is correct. This is the same as proving
2016 // "m >u 0" if and only if "x & (m - 1) <u m", i.e. "m >u 0 <=> x & (m - 1) <u m"
2017 //
2018 // We use (Lemma 1) and (Lemma 3) from above.
2019 //
2020 // Case "x & (m - 1) <u m => m >u 0":
2021 // We prove this by contradiction:
2022 // Assume m <=u 0 which is equivalent to m == 0:
2023 // and thus
2024 // x & (m - 1) <u m = 0 // m == 0
2025 // y <u 0 // y = x & (m - 1)
2026 // by Lemma 3, this is always false, i.e. a contradiction to our assumption.
2027 //
2028 // Case "m >u 0 => x & (m - 1) <u m":
2029 // x & (m - 1) <=u (m - 1) // (Lemma 1)
2030 // x & (m - 1) <=u (m - 1) <u m // Using assumption m >u 0, no underflow of "m - 1"
2031 //
2032 //
2033 // Note that the signed version of "m > 0":
2034 // m > 0 <=> x & (m - 1) <u m
2035 // does not hold:
2036 // Assume m == -1 and x == -1:
2037 // x & (m - 1) <u m
2038 // -1 & -2 <u -1
2039 // -2 <u -1
2040 // UINT_MAX - 1 <u UINT_MAX // Signed to unsigned numbers
2041 // which is true while
2042 // m > 0
2043 // is false which is a contradiction.
2044 //
2045 // (1a) and (1b) is covered by this method since we can directly return a true value as type while (2) is covered
2046 // in BoolNode::Ideal since we create a new non-constant node (see [CMPU_MASK]).
2047 const Type* BoolNode::Value_cmpu_and_mask(PhaseValues* phase) const {
2048 Node* cmp = in(1);
2049 if (cmp != nullptr && cmp->Opcode() == Op_CmpU) {
2050 Node* cmp1 = cmp->in(1);
2051 Node* cmp2 = cmp->in(2);
2052
2053 if (cmp1->Opcode() == Op_AndI) {
2054 Node* m = nullptr;
2055 if (_test._test == BoolTest::le) {
2056 // (1a) "((x & m) <=u m)", cmp2 = m
2057 m = cmp2;
2058 } else if (_test._test == BoolTest::lt && cmp2->Opcode() == Op_AddI && cmp2->in(2)->find_int_con(0) == 1) {
2059 // (1b) "(x & m) <u m + 1" and "(m & x) <u m + 1", cmp2 = m + 1
2060 Node* rhs_m = cmp2->in(1);
2061 const TypeInt* rhs_m_type = phase->type(rhs_m)->isa_int();
2062 if (rhs_m_type != nullptr && (rhs_m_type->_lo > -1 || rhs_m_type->_hi < -1)) {
2063 // Exclude any case where m == -1 is possible.
2064 m = rhs_m;
2065 }
2066 }
2067
2068 if (cmp1->in(2) == m || cmp1->in(1) == m) {
2069 return TypeInt::ONE;
2070 }
2071 }
2072 }
2073
2074 return nullptr;
2075 }
2076
2077 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
2078 // based on local information. If the input is constant, do it.
2079 const Type* BoolNode::Value(PhaseGVN* phase) const {
2080 const Type* input_type = phase->type(in(1));
2081 if (input_type == Type::TOP) {
2082 return Type::TOP;
2083 }
2084 const Type* t = Value_cmpu_and_mask(phase);
2085 if (t != nullptr) {
2086 return t;
2087 }
2088
2089 return _test.cc2logical(input_type);
2090 }
2091
2092 #ifndef PRODUCT
2093 //------------------------------dump_spec--------------------------------------
2094 // Dump special per-node info
2095 void BoolNode::dump_spec(outputStream *st) const {
2096 st->print("[");
2097 _test.dump_on(st);
2098 st->print("]");
2099 }
2100 #endif
2101
2102 //----------------------is_counted_loop_exit_test------------------------------
2103 // Returns true if node is used by a counted loop node.
2104 bool BoolNode::is_counted_loop_exit_test() {
2105 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
2106 Node* use = fast_out(i);
2107 if (use->is_CountedLoopEnd()) {
2108 return true;
2109 }
2110 }
2111 return false;
2112 }
2113
2114 //=============================================================================
2115 //------------------------------Value------------------------------------------
2116 const Type* AbsNode::Value(PhaseGVN* phase) const {
2117 const Type* t1 = phase->type(in(1));
2118 if (t1 == Type::TOP) return Type::TOP;
2119
2120 switch (t1->base()) {
2121 case Type::Int: {
2122 const TypeInt* ti = t1->is_int();
2123 if (ti->is_con()) {
2124 return TypeInt::make(g_uabs(ti->get_con()));
2125 }
2126 break;
2127 }
2128 case Type::Long: {
2129 const TypeLong* tl = t1->is_long();
2130 if (tl->is_con()) {
2131 return TypeLong::make(g_uabs(tl->get_con()));
2132 }
2133 break;
2134 }
2135 case Type::FloatCon:
2136 return TypeF::make(abs(t1->getf()));
2137 case Type::DoubleCon:
2138 return TypeD::make(abs(t1->getd()));
2139 default:
2140 break;
2141 }
2142
2143 return bottom_type();
2144 }
2145
2146 //------------------------------Identity----------------------------------------
2147 Node* AbsNode::Identity(PhaseGVN* phase) {
2148 Node* in1 = in(1);
2149 // No need to do abs for non-negative values
2150 if (phase->type(in1)->higher_equal(TypeInt::POS) ||
2151 phase->type(in1)->higher_equal(TypeLong::POS)) {
2152 return in1;
2153 }
2154 // Convert "abs(abs(x))" into "abs(x)"
2155 if (in1->Opcode() == Opcode()) {
2156 return in1;
2157 }
2158 return this;
2159 }
2160
2161 //------------------------------Ideal------------------------------------------
2162 Node* AbsNode::Ideal(PhaseGVN* phase, bool can_reshape) {
2163 Node* in1 = in(1);
2164 // Convert "abs(0-x)" into "abs(x)"
2165 if (in1->is_Sub() && phase->type(in1->in(1))->is_zero_type()) {
2166 set_req_X(1, in1->in(2), phase);
2167 return this;
2168 }
2169 return nullptr;
2170 }
2171
2172 //=============================================================================
2173 //------------------------------Value------------------------------------------
2174 // Compute sqrt
2175 const Type* SqrtDNode::Value(PhaseGVN* phase) const {
2176 const Type *t1 = phase->type( in(1) );
2177 if( t1 == Type::TOP ) return Type::TOP;
2178 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
2179 double d = t1->getd();
2180 if( d < 0.0 ) return Type::DOUBLE;
2181 return TypeD::make( sqrt( d ) );
2182 }
2183
2184 const Type* SqrtFNode::Value(PhaseGVN* phase) const {
2185 const Type *t1 = phase->type( in(1) );
2186 if( t1 == Type::TOP ) return Type::TOP;
2187 if( t1->base() != Type::FloatCon ) return Type::FLOAT;
2188 float f = t1->getf();
2189 if( f < 0.0f ) return Type::FLOAT;
2190 return TypeF::make( (float)sqrt( (double)f ) );
2191 }
2192
2193 const Type* SqrtHFNode::Value(PhaseGVN* phase) const {
2194 const Type* t1 = phase->type(in(1));
2195 if (t1 == Type::TOP) { return Type::TOP; }
2196 if (t1->base() != Type::HalfFloatCon) { return Type::HALF_FLOAT; }
2197 float f = t1->getf();
2198 if (f < 0.0f) return Type::HALF_FLOAT;
2199 return TypeH::make((float)sqrt((double)f));
2200 }
2201
2202 static const Type* reverse_bytes(int opcode, const Type* con) {
2203 switch (opcode) {
2204 // It is valid in bytecode to load any int and pass it to a method that expects a smaller type (i.e., short, char).
2205 // Let's cast the value to match the Java behavior.
2206 case Op_ReverseBytesS: return TypeInt::make(byteswap(static_cast<jshort>(con->is_int()->get_con())));
2207 case Op_ReverseBytesUS: return TypeInt::make(byteswap(static_cast<jchar>(con->is_int()->get_con())));
2208 case Op_ReverseBytesI: return TypeInt::make(byteswap(con->is_int()->get_con()));
2209 case Op_ReverseBytesL: return TypeLong::make(byteswap(con->is_long()->get_con()));
2210 default: ShouldNotReachHere();
2211 }
2212 }
2213
2214 const Type* ReverseBytesNode::Value(PhaseGVN* phase) const {
2215 const Type* type = phase->type(in(1));
2216 if (type == Type::TOP) {
2217 return Type::TOP;
2218 }
2219 if (type->singleton()) {
2220 return reverse_bytes(Opcode(), type);
2221 }
2222 return bottom_type();
2223 }
2224
2225 const Type* ReverseINode::Value(PhaseGVN* phase) const {
2226 const Type *t1 = phase->type( in(1) );
2227 if (t1 == Type::TOP) {
2228 return Type::TOP;
2229 }
2230 const TypeInt* t1int = t1->isa_int();
2231 if (t1int && t1int->is_con()) {
2232 jint res = reverse_bits(t1int->get_con());
2233 return TypeInt::make(res);
2234 }
2235 return bottom_type();
2236 }
2237
2238 const Type* ReverseLNode::Value(PhaseGVN* phase) const {
2239 const Type *t1 = phase->type( in(1) );
2240 if (t1 == Type::TOP) {
2241 return Type::TOP;
2242 }
2243 const TypeLong* t1long = t1->isa_long();
2244 if (t1long && t1long->is_con()) {
2245 jlong res = reverse_bits(t1long->get_con());
2246 return TypeLong::make(res);
2247 }
2248 return bottom_type();
2249 }
2250
2251 Node* ReverseINode::Identity(PhaseGVN* phase) {
2252 if (in(1)->Opcode() == Op_ReverseI) {
2253 return in(1)->in(1);
2254 }
2255 return this;
2256 }
2257
2258 Node* ReverseLNode::Identity(PhaseGVN* phase) {
2259 if (in(1)->Opcode() == Op_ReverseL) {
2260 return in(1)->in(1);
2261 }
2262 return this;
2263 }