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.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
24
25 #include "compiler/compileLog.hpp"
26 #include "gc/shared/barrierSet.hpp"
27 #include "gc/shared/c2/barrierSetC2.hpp"
28 #include "memory/allocation.inline.hpp"
29 #include "opto/addnode.hpp"
30 #include "opto/callnode.hpp"
31 #include "opto/cfgnode.hpp"
32 #include "opto/inlinetypenode.hpp"
33 #include "opto/loopnode.hpp"
34 #include "opto/matcher.hpp"
35 #include "opto/movenode.hpp"
36 #include "opto/mulnode.hpp"
37 #include "opto/opaquenode.hpp"
38 #include "opto/opcodes.hpp"
39 #include "opto/phaseX.hpp"
40 #include "opto/subnode.hpp"
41 #include "runtime/sharedRuntime.hpp"
42 #include "utilities/reverse_bits.hpp"
43
44 // Portions of code courtesy of Clifford Click
45
46 // Optimization - Graph Style
47
48 #include "math.h"
49
50 //=============================================================================
51 //------------------------------Identity---------------------------------------
52 // If right input is a constant 0, return the left input.
53 Node* SubNode::Identity(PhaseGVN* phase) {
54 assert(in(1) != this, "Must already have called Value");
55 assert(in(2) != this, "Must already have called Value");
56
57 const Type* zero = add_id();
58
59 // Remove double negation if it is not a floating point number since negation
60 // is not the same as subtraction for floating point numbers
61 // (cf. JLS § 15.15.4). `0-(0-(-0.0))` must be equal to positive 0.0 according to
62 // JLS § 15.8.2, but would result in -0.0 if this folding would be applied.
63 if (phase->type(in(1))->higher_equal(zero) &&
64 in(2)->Opcode() == Opcode() &&
65 phase->type(in(2)->in(1))->higher_equal(zero) &&
66 !phase->type(in(2)->in(2))->is_floatingpoint()) {
67 return in(2)->in(2);
68 }
69
70 // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y
71 if (in(1)->Opcode() == Op_AddI || in(1)->Opcode() == Op_AddL) {
72 if (in(1)->in(2) == in(2)) {
73 return in(1)->in(1);
74 }
75 if (in(1)->in(1) == in(2)) {
76 return in(1)->in(2);
77 }
78 }
79
80 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this;
81 }
82
83 //------------------------------Value------------------------------------------
84 // A subtract node differences it's two inputs.
85 const Type* SubNode::Value_common(PhaseValues* phase) const {
86 const Node* in1 = in(1);
87 const Node* in2 = in(2);
88 // Either input is TOP ==> the result is TOP
89 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
90 if( t1 == Type::TOP ) return Type::TOP;
91 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
92 if( t2 == Type::TOP ) return Type::TOP;
93
94 // Not correct for SubFnode and AddFNode (must check for infinity)
95 // Equal? Subtract is zero
96 if (in1->eqv_uncast(in2)) return add_id();
97
98 // Either input is BOTTOM ==> the result is the local BOTTOM
99 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM )
100 return bottom_type();
101
102 return nullptr;
103 }
104
105 const Type* SubNode::Value(PhaseGVN* phase) const {
106 const Type* t = Value_common(phase);
107 if (t != nullptr) {
108 return t;
109 }
110 const Type* t1 = phase->type(in(1));
111 const Type* t2 = phase->type(in(2));
112 return sub(t1,t2); // Local flavor of type subtraction
113
114 }
115
116 SubNode* SubNode::make(Node* in1, Node* in2, BasicType bt) {
117 switch (bt) {
118 case T_INT:
119 return new SubINode(in1, in2);
120 case T_LONG:
121 return new SubLNode(in1, in2);
122 default:
123 fatal("Not implemented for %s", type2name(bt));
124 }
125 return nullptr;
126 }
127
128 //=============================================================================
129 //------------------------------Helper function--------------------------------
130
131 static bool is_cloop_increment(Node* inc) {
132 precond(inc->Opcode() == Op_AddI || inc->Opcode() == Op_AddL);
133
134 if (!inc->in(1)->is_Phi()) {
135 return false;
136 }
137 const PhiNode* phi = inc->in(1)->as_Phi();
138
139 if (!phi->region()->is_CountedLoop()) {
140 return false;
141 }
142
143 return inc == phi->region()->as_CountedLoop()->incr();
144 }
145
146 // Given the expression '(x + C) - v', or
147 // 'v - (x + C)', we examine nodes '+' and 'v':
148 //
149 // 1. Do not convert if '+' is a counted-loop increment, because the '-' is
150 // loop invariant and converting extends the live-range of 'x' to overlap
151 // with the '+', forcing another register to be used in the loop.
152 //
153 // 2. Do not convert if 'v' is a counted-loop induction variable, because
154 // 'x' might be invariant.
155 //
156 static bool ok_to_convert(Node* inc, Node* var) {
157 return !(is_cloop_increment(inc) || var->is_cloop_ind_var());
158 }
159
160 static bool is_cloop_condition(BoolNode* bol) {
161 for (DUIterator_Fast imax, i = bol->fast_outs(imax); i < imax; i++) {
162 Node* out = bol->fast_out(i);
163 if (out->is_BaseCountedLoopEnd()) {
164 return true;
165 }
166 }
167 return false;
168 }
169
170 //------------------------------Ideal------------------------------------------
171 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){
172 Node *in1 = in(1);
173 Node *in2 = in(2);
174 uint op1 = in1->Opcode();
175 uint op2 = in2->Opcode();
176
177 #ifdef ASSERT
178 // Check for dead loop
179 if ((in1 == this) || (in2 == this) ||
180 ((op1 == Op_AddI || op1 == Op_SubI) &&
181 ((in1->in(1) == this) || (in1->in(2) == this) ||
182 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
183 assert(false, "dead loop in SubINode::Ideal");
184 }
185 #endif
186
187 const Type *t2 = phase->type( in2 );
188 if( t2 == Type::TOP ) return nullptr;
189 // Convert "x-c0" into "x+ -c0".
190 if( t2->base() == Type::Int ){ // Might be bottom or top...
191 const TypeInt *i = t2->is_int();
192 if( i->is_con() )
193 return new AddINode(in1, phase->intcon(java_negate(i->get_con())));
194 }
195
196 // Convert "(x+c0) - y" into (x-y) + c0"
197 // Do not collapse (x+c0)-y if "+" is a loop increment or
198 // if "y" is a loop induction variable.
199 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) {
200 const Type *tadd = phase->type( in1->in(2) );
201 if( tadd->singleton() && tadd != Type::TOP ) {
202 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 ));
203 return new AddINode( sub2, in1->in(2) );
204 }
205 }
206
207 // Convert "x - (y+c0)" into "(x-y) - c0" AND
208 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
209 // Need the same check as in above optimization but reversed.
210 if (op2 == Op_AddI
211 && ok_to_convert(in2, in1)
212 && in2->in(2)->Opcode() == Op_ConI) {
213 jint c0 = phase->type(in2->in(2))->isa_int()->get_con();
214 Node* in21 = in2->in(1);
215 if (in1->Opcode() == Op_ConI) {
216 // Match c1
217 jint c1 = phase->type(in1)->isa_int()->get_con();
218 Node* sub2 = phase->intcon(java_subtract(c1, c0));
219 return new SubINode(sub2, in21);
220 } else {
221 // Match x
222 Node* sub2 = phase->transform(new SubINode(in1, in21));
223 Node* neg_c0 = phase->intcon(java_negate(c0));
224 return new AddINode(sub2, neg_c0);
225 }
226 }
227
228 const Type *t1 = phase->type( in1 );
229 if( t1 == Type::TOP ) return nullptr;
230
231 #ifdef ASSERT
232 // Check for dead loop
233 if ((op2 == Op_AddI || op2 == Op_SubI) &&
234 ((in2->in(1) == this) || (in2->in(2) == this) ||
235 (in2->in(1) == in2) || (in2->in(2) == in2))) {
236 assert(false, "dead loop in SubINode::Ideal");
237 }
238 #endif
239
240 // Convert "x - (x+y)" into "-y"
241 if (op2 == Op_AddI && in1 == in2->in(1)) {
242 return new SubINode(phase->intcon(0), in2->in(2));
243 }
244 // Convert "(x-y) - x" into "-y"
245 if (op1 == Op_SubI && in1->in(1) == in2) {
246 return new SubINode(phase->intcon(0), in1->in(2));
247 }
248 // Convert "x - (y+x)" into "-y"
249 if (op2 == Op_AddI && in1 == in2->in(2)) {
250 return new SubINode(phase->intcon(0), in2->in(1));
251 }
252
253 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity().
254 if (t1 == TypeInt::ZERO && op2 == Op_SubI && phase->type(in2->in(1)) != TypeInt::ZERO) {
255 return new SubINode(in2->in(2), in2->in(1));
256 }
257
258 // Convert "0 - (x+con)" into "-con-x"
259 jint con;
260 if( t1 == TypeInt::ZERO && op2 == Op_AddI &&
261 (con = in2->in(2)->find_int_con(0)) != 0 )
262 return new SubINode( phase->intcon(-con), in2->in(1) );
263
264 // Convert "(X+A) - (X+B)" into "A - B"
265 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) )
266 return new SubINode( in1->in(2), in2->in(2) );
267
268 // Convert "(A+X) - (B+X)" into "A - B"
269 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) )
270 return new SubINode( in1->in(1), in2->in(1) );
271
272 // Convert "(A+X) - (X+B)" into "A - B"
273 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) )
274 return new SubINode( in1->in(1), in2->in(2) );
275
276 // Convert "(X+A) - (B+X)" into "A - B"
277 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) )
278 return new SubINode( in1->in(2), in2->in(1) );
279
280 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally
281 // nicer to optimize than subtract.
282 if( op2 == Op_SubI && in2->outcnt() == 1) {
283 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) );
284 return new SubINode( add1, in2->in(1) );
285 }
286
287 // Associative
288 if (op1 == Op_MulI && op2 == Op_MulI) {
289 Node* sub_in1 = nullptr;
290 Node* sub_in2 = nullptr;
291 Node* mul_in = nullptr;
292
293 if (in1->in(1) == in2->in(1)) {
294 // Convert "a*b-a*c into a*(b-c)
295 sub_in1 = in1->in(2);
296 sub_in2 = in2->in(2);
297 mul_in = in1->in(1);
298 } else if (in1->in(2) == in2->in(1)) {
299 // Convert a*b-b*c into b*(a-c)
300 sub_in1 = in1->in(1);
301 sub_in2 = in2->in(2);
302 mul_in = in1->in(2);
303 } else if (in1->in(2) == in2->in(2)) {
304 // Convert a*c-b*c into (a-b)*c
305 sub_in1 = in1->in(1);
306 sub_in2 = in2->in(1);
307 mul_in = in1->in(2);
308 } else if (in1->in(1) == in2->in(2)) {
309 // Convert a*b-c*a into a*(b-c)
310 sub_in1 = in1->in(2);
311 sub_in2 = in2->in(1);
312 mul_in = in1->in(1);
313 }
314
315 if (mul_in != nullptr) {
316 Node* sub = phase->transform(new SubINode(sub_in1, sub_in2));
317 return new MulINode(mul_in, sub);
318 }
319 }
320
321 // Convert "0-(A>>31)" into "(A>>>31)"
322 if ( op2 == Op_RShiftI ) {
323 Node *in21 = in2->in(1);
324 Node *in22 = in2->in(2);
325 const TypeInt *zero = phase->type(in1)->isa_int();
326 const TypeInt *t21 = phase->type(in21)->isa_int();
327 const TypeInt *t22 = phase->type(in22)->isa_int();
328 if ( t21 && t22 && zero == TypeInt::ZERO && t22->is_con(31) ) {
329 return new URShiftINode(in21, in22);
330 }
331 }
332
333 return nullptr;
334 }
335
336 //------------------------------sub--------------------------------------------
337 // A subtract node differences it's two inputs.
338 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const {
339 const TypeInt *r0 = t1->is_int(); // Handy access
340 const TypeInt *r1 = t2->is_int();
341 int32_t lo = java_subtract(r0->_lo, r1->_hi);
342 int32_t hi = java_subtract(r0->_hi, r1->_lo);
343
344 // We next check for 32-bit overflow.
345 // If that happens, we just assume all integers are possible.
346 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
347 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
348 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
349 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
350 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen));
351 else // Overflow; assume all integers
352 return TypeInt::INT;
353 }
354
355 //=============================================================================
356 //------------------------------Ideal------------------------------------------
357 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
358 Node *in1 = in(1);
359 Node *in2 = in(2);
360 uint op1 = in1->Opcode();
361 uint op2 = in2->Opcode();
362
363 #ifdef ASSERT
364 // Check for dead loop
365 if ((in1 == this) || (in2 == this) ||
366 ((op1 == Op_AddL || op1 == Op_SubL) &&
367 ((in1->in(1) == this) || (in1->in(2) == this) ||
368 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
369 assert(false, "dead loop in SubLNode::Ideal");
370 }
371 #endif
372
373 if( phase->type( in2 ) == Type::TOP ) return nullptr;
374 const TypeLong *i = phase->type( in2 )->isa_long();
375 // Convert "x-c0" into "x+ -c0".
376 if( i && // Might be bottom or top...
377 i->is_con() )
378 return new AddLNode(in1, phase->longcon(java_negate(i->get_con())));
379
380 // Convert "(x+c0) - y" into (x-y) + c0"
381 // Do not collapse (x+c0)-y if "+" is a loop increment or
382 // if "y" is a loop induction variable.
383 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) {
384 Node *in11 = in1->in(1);
385 const Type *tadd = phase->type( in1->in(2) );
386 if( tadd->singleton() && tadd != Type::TOP ) {
387 Node *sub2 = phase->transform( new SubLNode( in11, in2 ));
388 return new AddLNode( sub2, in1->in(2) );
389 }
390 }
391
392 // Convert "x - (y+c0)" into "(x-y) - c0" AND
393 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
394 // Need the same check as in above optimization but reversed.
395 if (op2 == Op_AddL
396 && ok_to_convert(in2, in1)
397 && in2->in(2)->Opcode() == Op_ConL) {
398 jlong c0 = phase->type(in2->in(2))->isa_long()->get_con();
399 Node* in21 = in2->in(1);
400 if (in1->Opcode() == Op_ConL) {
401 // Match c1
402 jlong c1 = phase->type(in1)->isa_long()->get_con();
403 Node* sub2 = phase->longcon(java_subtract(c1, c0));
404 return new SubLNode(sub2, in21);
405 } else {
406 Node* sub2 = phase->transform(new SubLNode(in1, in21));
407 Node* neg_c0 = phase->longcon(java_negate(c0));
408 return new AddLNode(sub2, neg_c0);
409 }
410 }
411
412 const Type *t1 = phase->type( in1 );
413 if( t1 == Type::TOP ) return nullptr;
414
415 #ifdef ASSERT
416 // Check for dead loop
417 if ((op2 == Op_AddL || op2 == Op_SubL) &&
418 ((in2->in(1) == this) || (in2->in(2) == this) ||
419 (in2->in(1) == in2) || (in2->in(2) == in2))) {
420 assert(false, "dead loop in SubLNode::Ideal");
421 }
422 #endif
423
424 // Convert "x - (x+y)" into "-y"
425 if (op2 == Op_AddL && in1 == in2->in(1)) {
426 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(2));
427 }
428 // Convert "(x-y) - x" into "-y"
429 if (op1 == Op_SubL && in1->in(1) == in2) {
430 return new SubLNode(phase->makecon(TypeLong::ZERO), in1->in(2));
431 }
432 // Convert "x - (y+x)" into "-y"
433 if (op2 == Op_AddL && in1 == in2->in(2)) {
434 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(1));
435 }
436
437 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity.
438 if (t1 == TypeLong::ZERO && op2 == Op_SubL && phase->type(in2->in(1)) != TypeLong::ZERO) {
439 return new SubLNode(in2->in(2), in2->in(1));
440 }
441
442 // Convert "(X+A) - (X+B)" into "A - B"
443 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) )
444 return new SubLNode( in1->in(2), in2->in(2) );
445
446 // Convert "(A+X) - (B+X)" into "A - B"
447 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) )
448 return new SubLNode( in1->in(1), in2->in(1) );
449
450 // Convert "(A+X) - (X+B)" into "A - B"
451 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(1) )
452 return new SubLNode( in1->in(1), in2->in(2) );
453
454 // Convert "(X+A) - (B+X)" into "A - B"
455 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(2) )
456 return new SubLNode( in1->in(2), in2->in(1) );
457
458 // Convert "A-(B-C)" into (A+C)-B"
459 if( op2 == Op_SubL && in2->outcnt() == 1) {
460 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) );
461 return new SubLNode( add1, in2->in(1) );
462 }
463
464 // Associative
465 if (op1 == Op_MulL && op2 == Op_MulL) {
466 Node* sub_in1 = nullptr;
467 Node* sub_in2 = nullptr;
468 Node* mul_in = nullptr;
469
470 if (in1->in(1) == in2->in(1)) {
471 // Convert "a*b-a*c into a*(b+c)
472 sub_in1 = in1->in(2);
473 sub_in2 = in2->in(2);
474 mul_in = in1->in(1);
475 } else if (in1->in(2) == in2->in(1)) {
476 // Convert a*b-b*c into b*(a-c)
477 sub_in1 = in1->in(1);
478 sub_in2 = in2->in(2);
479 mul_in = in1->in(2);
480 } else if (in1->in(2) == in2->in(2)) {
481 // Convert a*c-b*c into (a-b)*c
482 sub_in1 = in1->in(1);
483 sub_in2 = in2->in(1);
484 mul_in = in1->in(2);
485 } else if (in1->in(1) == in2->in(2)) {
486 // Convert a*b-c*a into a*(b-c)
487 sub_in1 = in1->in(2);
488 sub_in2 = in2->in(1);
489 mul_in = in1->in(1);
490 }
491
492 if (mul_in != nullptr) {
493 Node* sub = phase->transform(new SubLNode(sub_in1, sub_in2));
494 return new MulLNode(mul_in, sub);
495 }
496 }
497
498 // Convert "0L-(A>>63)" into "(A>>>63)"
499 if ( op2 == Op_RShiftL ) {
500 Node *in21 = in2->in(1);
501 Node *in22 = in2->in(2);
502 const TypeLong *zero = phase->type(in1)->isa_long();
503 const TypeLong *t21 = phase->type(in21)->isa_long();
504 const TypeInt *t22 = phase->type(in22)->isa_int();
505 if ( t21 && t22 && zero == TypeLong::ZERO && t22->is_con(63) ) {
506 return new URShiftLNode(in21, in22);
507 }
508 }
509
510 return nullptr;
511 }
512
513 //------------------------------sub--------------------------------------------
514 // A subtract node differences it's two inputs.
515 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const {
516 const TypeLong *r0 = t1->is_long(); // Handy access
517 const TypeLong *r1 = t2->is_long();
518 jlong lo = java_subtract(r0->_lo, r1->_hi);
519 jlong hi = java_subtract(r0->_hi, r1->_lo);
520
521 // We next check for 32-bit overflow.
522 // If that happens, we just assume all integers are possible.
523 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
524 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
525 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
526 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
527 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen));
528 else // Overflow; assume all integers
529 return TypeLong::LONG;
530 }
531
532 //=============================================================================
533 //------------------------------Value------------------------------------------
534 // A subtract node differences its two inputs.
535 const Type* SubFPNode::Value(PhaseGVN* phase) const {
536 const Node* in1 = in(1);
537 const Node* in2 = in(2);
538 // Either input is TOP ==> the result is TOP
539 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
540 if( t1 == Type::TOP ) return Type::TOP;
541 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
542 if( t2 == Type::TOP ) return Type::TOP;
543
544 // if both operands are infinity of same sign, the result is NaN; do
545 // not replace with zero
546 if (t1->is_finite() && t2->is_finite() && in1 == in2) {
547 return add_id();
548 }
549
550 // Either input is BOTTOM ==> the result is the local BOTTOM
551 const Type *bot = bottom_type();
552 if( (t1 == bot) || (t2 == bot) ||
553 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
554 return bot;
555
556 return sub(t1,t2); // Local flavor of type subtraction
557 }
558
559
560 //=============================================================================
561 //------------------------------sub--------------------------------------------
562 // A subtract node differences its two inputs.
563 const Type* SubHFNode::sub(const Type* t1, const Type* t2) const {
564 // Half precision floating point subtraction follows the rules of IEEE 754
565 // applicable to other floating point types.
566 if (t1->isa_half_float_constant() != nullptr &&
567 t2->isa_half_float_constant() != nullptr) {
568 return TypeH::make(t1->getf() - t2->getf());
569 } else {
570 return Type::HALF_FLOAT;
571 }
572 }
573
574 //------------------------------Ideal------------------------------------------
575 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
576 const Type *t2 = phase->type( in(2) );
577 // Convert "x-c0" into "x+ -c0".
578 if( t2->base() == Type::FloatCon ) { // Might be bottom or top...
579 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) );
580 }
581
582 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes
583 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0.
584 //if( phase->type(in(1)) == TypeF::ZERO )
585 //return new (phase->C, 2) NegFNode(in(2));
586
587 return nullptr;
588 }
589
590 //------------------------------sub--------------------------------------------
591 // A subtract node differences its two inputs.
592 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const {
593 // no folding if one of operands is infinity or NaN, do not do constant folding
594 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) {
595 return TypeF::make( t1->getf() - t2->getf() );
596 }
597 else if( g_isnan(t1->getf()) ) {
598 return t1;
599 }
600 else if( g_isnan(t2->getf()) ) {
601 return t2;
602 }
603 else {
604 return Type::FLOAT;
605 }
606 }
607
608 //=============================================================================
609 //------------------------------Ideal------------------------------------------
610 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){
611 const Type *t2 = phase->type( in(2) );
612 // Convert "x-c0" into "x+ -c0".
613 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top...
614 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) );
615 }
616
617 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes
618 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0.
619 //if( phase->type(in(1)) == TypeD::ZERO )
620 //return new (phase->C, 2) NegDNode(in(2));
621
622 return nullptr;
623 }
624
625 //------------------------------sub--------------------------------------------
626 // A subtract node differences its two inputs.
627 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const {
628 // no folding if one of operands is infinity or NaN, do not do constant folding
629 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) {
630 return TypeD::make( t1->getd() - t2->getd() );
631 }
632 else if( g_isnan(t1->getd()) ) {
633 return t1;
634 }
635 else if( g_isnan(t2->getd()) ) {
636 return t2;
637 }
638 else {
639 return Type::DOUBLE;
640 }
641 }
642
643 //=============================================================================
644 //------------------------------Idealize---------------------------------------
645 // Unlike SubNodes, compare must still flatten return value to the
646 // range -1, 0, 1.
647 // And optimizations like those for (X + Y) - X fail if overflow happens.
648 Node* CmpNode::Identity(PhaseGVN* phase) {
649 return this;
650 }
651
652 CmpNode *CmpNode::make(Node *in1, Node *in2, BasicType bt, bool unsigned_comp) {
653 switch (bt) {
654 case T_INT:
655 if (unsigned_comp) {
656 return new CmpUNode(in1, in2);
657 }
658 return new CmpINode(in1, in2);
659 case T_LONG:
660 if (unsigned_comp) {
661 return new CmpULNode(in1, in2);
662 }
663 return new CmpLNode(in1, in2);
664 case T_OBJECT:
665 case T_ARRAY:
666 case T_ADDRESS:
667 case T_METADATA:
668 return new CmpPNode(in1, in2);
669 case T_NARROWOOP:
670 case T_NARROWKLASS:
671 return new CmpNNode(in1, in2);
672 default:
673 fatal("Not implemented for %s", type2name(bt));
674 }
675 return nullptr;
676 }
677
678 //=============================================================================
679 //------------------------------cmp--------------------------------------------
680 // Simplify a CmpI (compare 2 integers) node, based on local information.
681 // If both inputs are constants, compare them.
682 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const {
683 const TypeInt *r0 = t1->is_int(); // Handy access
684 const TypeInt *r1 = t2->is_int();
685
686 if( r0->_hi < r1->_lo ) // Range is always low?
687 return TypeInt::CC_LT;
688 else if( r0->_lo > r1->_hi ) // Range is always high?
689 return TypeInt::CC_GT;
690
691 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
692 assert(r0->get_con() == r1->get_con(), "must be equal");
693 return TypeInt::CC_EQ; // Equal results.
694 } else if( r0->_hi == r1->_lo ) // Range is never high?
695 return TypeInt::CC_LE;
696 else if( r0->_lo == r1->_hi ) // Range is never low?
697 return TypeInt::CC_GE;
698 return TypeInt::CC; // else use worst case results
699 }
700
701 const Type* CmpINode::Value(PhaseGVN* phase) const {
702 Node* in1 = in(1);
703 Node* in2 = in(2);
704 // If this test is the zero trip guard for a main or post loop, check whether, with the opaque node removed, the test
705 // would constant fold so the loop is never entered. If so return the type of the test without the opaque node removed:
706 // make the loop unreachable.
707 // The reason for this is that the iv phi captures the bounds of the loop and if the loop becomes unreachable, it can
708 // become top. In that case, the loop must be removed.
709 // This is safe because:
710 // - as optimizations proceed, the range of iterations executed by the main loop narrows. If no iterations remain, then
711 // we're done with optimizations for that loop.
712 // - the post loop is initially not reachable but as long as there's a main loop, the zero trip guard for the post
713 // 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
714 // loop is removed, there's no need to preserve the zero trip guard for the post loop anymore.
715 if (in1 != nullptr && in2 != nullptr) {
716 uint input = 0;
717 Node* cmp = nullptr;
718 BoolTest::mask test;
719 if (in1->Opcode() == Op_OpaqueZeroTripGuard && phase->type(in1) != Type::TOP) {
720 cmp = new CmpINode(in1->in(1), in2);
721 test = ((OpaqueZeroTripGuardNode*)in1)->_loop_entered_mask;
722 }
723 if (in2->Opcode() == Op_OpaqueZeroTripGuard && phase->type(in2) != Type::TOP) {
724 assert(cmp == nullptr, "A cmp with 2 OpaqueZeroTripGuard inputs");
725 cmp = new CmpINode(in1, in2->in(1));
726 test = ((OpaqueZeroTripGuardNode*)in2)->_loop_entered_mask;
727 }
728 if (cmp != nullptr) {
729 const Type* cmp_t = cmp->Value(phase);
730 const Type* t = BoolTest(test).cc2logical(cmp_t);
731 cmp->destruct(phase);
732 if (t == TypeInt::ZERO) {
733 return cmp_t;
734 }
735 }
736 }
737
738 return SubNode::Value(phase);
739 }
740
741
742 // Simplify a CmpU (compare 2 integers) node, based on local information.
743 // If both inputs are constants, compare them.
744 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const {
745 assert(!t1->isa_ptr(), "obsolete usage of CmpU");
746
747 // comparing two unsigned ints
748 const TypeInt *r0 = t1->is_int(); // Handy access
749 const TypeInt *r1 = t2->is_int();
750
751 // Current installed version
752 // Compare ranges for non-overlap
753 juint lo0 = r0->_lo;
754 juint hi0 = r0->_hi;
755 juint lo1 = r1->_lo;
756 juint hi1 = r1->_hi;
757
758 // If either one has both negative and positive values,
759 // it therefore contains both 0 and -1, and since [0..-1] is the
760 // full unsigned range, the type must act as an unsigned bottom.
761 bool bot0 = ((jint)(lo0 ^ hi0) < 0);
762 bool bot1 = ((jint)(lo1 ^ hi1) < 0);
763
764 if (bot0 || bot1) {
765 // All unsigned values are LE -1 and GE 0.
766 if (lo0 == 0 && hi0 == 0) {
767 return TypeInt::CC_LE; // 0 <= bot
768 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) {
769 return TypeInt::CC_GE; // -1 >= bot
770 } else if (lo1 == 0 && hi1 == 0) {
771 return TypeInt::CC_GE; // bot >= 0
772 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) {
773 return TypeInt::CC_LE; // bot <= -1
774 }
775 } else {
776 // We can use ranges of the form [lo..hi] if signs are the same.
777 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
778 // results are reversed, '-' > '+' for unsigned compare
779 if (hi0 < lo1) {
780 return TypeInt::CC_LT; // smaller
781 } else if (lo0 > hi1) {
782 return TypeInt::CC_GT; // greater
783 } else if (hi0 == lo1 && lo0 == hi1) {
784 return TypeInt::CC_EQ; // Equal results
785 } else if (lo0 >= hi1) {
786 return TypeInt::CC_GE;
787 } else if (hi0 <= lo1) {
788 // Check for special case in Hashtable::get. (See below.)
789 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
790 return TypeInt::CC_LT;
791 return TypeInt::CC_LE;
792 }
793 }
794 // Check for special case in Hashtable::get - the hash index is
795 // mod'ed to the table size so the following range check is useless.
796 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have
797 // to be positive.
798 // (This is a gross hack, since the sub method never
799 // looks at the structure of the node in any other case.)
800 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
801 return TypeInt::CC_LT;
802 return TypeInt::CC; // else use worst case results
803 }
804
805 const Type* CmpUNode::Value(PhaseGVN* phase) const {
806 const Type* t = SubNode::Value_common(phase);
807 if (t != nullptr) {
808 return t;
809 }
810 const Node* in1 = in(1);
811 const Node* in2 = in(2);
812 const Type* t1 = phase->type(in1);
813 const Type* t2 = phase->type(in2);
814 assert(t1->isa_int(), "CmpU has only Int type inputs");
815 if (t2 == TypeInt::INT) { // Compare to bottom?
816 return bottom_type();
817 }
818
819 const Type* t_sub = sub(t1, t2); // compare based on immediate inputs
820
821 uint in1_op = in1->Opcode();
822 if (in1_op == Op_AddI || in1_op == Op_SubI) {
823 // The problem rise when result of AddI(SubI) may overflow
824 // signed integer value. Let say the input type is
825 // [256, maxint] then +128 will create 2 ranges due to
826 // overflow: [minint, minint+127] and [384, maxint].
827 // But C2 type system keep only 1 type range and as result
828 // it use general [minint, maxint] for this case which we
829 // can't optimize.
830 //
831 // Make 2 separate type ranges based on types of AddI(SubI) inputs
832 // and compare results of their compare. If results are the same
833 // CmpU node can be optimized.
834 const Node* in11 = in1->in(1);
835 const Node* in12 = in1->in(2);
836 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11);
837 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12);
838 // Skip cases when input types are top or bottom.
839 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) &&
840 (t12 != Type::TOP) && (t12 != TypeInt::INT)) {
841 const TypeInt *r0 = t11->is_int();
842 const TypeInt *r1 = t12->is_int();
843 jlong lo_r0 = r0->_lo;
844 jlong hi_r0 = r0->_hi;
845 jlong lo_r1 = r1->_lo;
846 jlong hi_r1 = r1->_hi;
847 if (in1_op == Op_SubI) {
848 jlong tmp = hi_r1;
849 hi_r1 = -lo_r1;
850 lo_r1 = -tmp;
851 // Note, for substructing [minint,x] type range
852 // long arithmetic provides correct overflow answer.
853 // The confusion come from the fact that in 32-bit
854 // -minint == minint but in 64-bit -minint == maxint+1.
855 }
856 jlong lo_long = lo_r0 + lo_r1;
857 jlong hi_long = hi_r0 + hi_r1;
858 int lo_tr1 = min_jint;
859 int hi_tr1 = (int)hi_long;
860 int lo_tr2 = (int)lo_long;
861 int hi_tr2 = max_jint;
862 bool underflow = lo_long != (jlong)lo_tr2;
863 bool overflow = hi_long != (jlong)hi_tr1;
864 // Use sub(t1, t2) when there is no overflow (one type range)
865 // or when both overflow and underflow (too complex).
866 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) {
867 // Overflow only on one boundary, compare 2 separate type ranges.
868 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
869 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w);
870 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w);
871 const TypeInt* cmp1 = sub(tr1, t2)->is_int();
872 const TypeInt* cmp2 = sub(tr2, t2)->is_int();
873 // Compute union, so that cmp handles all possible results from the two cases
874 const Type* t_cmp = cmp1->meet(cmp2);
875 // Pick narrowest type, based on overflow computation and on immediate inputs
876 return t_sub->filter(t_cmp);
877 }
878 }
879 }
880
881 return t_sub;
882 }
883
884 bool CmpUNode::is_index_range_check() const {
885 // Check for the "(X ModI Y) CmpU Y" shape
886 return (in(1)->Opcode() == Op_ModI &&
887 in(1)->in(2)->eqv_uncast(in(2)));
888 }
889
890 //------------------------------Idealize---------------------------------------
891 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
892 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) {
893 switch (in(1)->Opcode()) {
894 case Op_CmpU3: // Collapse a CmpU3/CmpI into a CmpU
895 return new CmpUNode(in(1)->in(1),in(1)->in(2));
896 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL
897 return new CmpLNode(in(1)->in(1),in(1)->in(2));
898 case Op_CmpUL3: // Collapse a CmpUL3/CmpI into a CmpUL
899 return new CmpULNode(in(1)->in(1),in(1)->in(2));
900 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF
901 return new CmpFNode(in(1)->in(1),in(1)->in(2));
902 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD
903 return new CmpDNode(in(1)->in(1),in(1)->in(2));
904 //case Op_SubI:
905 // If (x - y) cannot overflow, then ((x - y) <?> 0)
906 // can be turned into (x <?> y).
907 // This is handled (with more general cases) by Ideal_sub_algebra.
908 }
909 }
910 return nullptr; // No change
911 }
912
913 //------------------------------Ideal------------------------------------------
914 Node* CmpLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
915 Node* a = nullptr;
916 Node* b = nullptr;
917 if (is_double_null_check(phase, a, b) && (phase->type(a)->is_zero_type() || phase->type(b)->is_zero_type())) {
918 // Degraded to a simple null check, use old acmp
919 return new CmpPNode(a, b);
920 }
921 const TypeLong *t2 = phase->type(in(2))->isa_long();
922 if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) {
923 const jlong con = t2->get_con();
924 if (con >= min_jint && con <= max_jint) {
925 return new CmpINode(in(1)->in(1), phase->intcon((jint)con));
926 }
927 }
928 return nullptr;
929 }
930
931 // Match double null check emitted by Compile::optimize_acmp()
932 bool CmpLNode::is_double_null_check(PhaseGVN* phase, Node*& a, Node*& b) const {
933 if (in(1)->Opcode() == Op_OrL &&
934 in(1)->in(1)->Opcode() == Op_CastP2X &&
935 in(1)->in(2)->Opcode() == Op_CastP2X &&
936 in(2)->bottom_type()->is_zero_type()) {
937 assert(EnableValhalla, "unexpected double null check");
938 a = in(1)->in(1)->in(1);
939 b = in(1)->in(2)->in(1);
940 return true;
941 }
942 return false;
943 }
944
945 //------------------------------Value------------------------------------------
946 const Type* CmpLNode::Value(PhaseGVN* phase) const {
947 Node* a = nullptr;
948 Node* b = nullptr;
949 if (is_double_null_check(phase, a, b) && (!phase->type(a)->maybe_null() || !phase->type(b)->maybe_null())) {
950 // One operand is never nullptr, emit constant false
951 return TypeInt::CC_GT;
952 }
953 return SubNode::Value(phase);
954 }
955
956 //=============================================================================
957 // Simplify a CmpL (compare 2 longs ) node, based on local information.
958 // If both inputs are constants, compare them.
959 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const {
960 const TypeLong *r0 = t1->is_long(); // Handy access
961 const TypeLong *r1 = t2->is_long();
962
963 if( r0->_hi < r1->_lo ) // Range is always low?
964 return TypeInt::CC_LT;
965 else if( r0->_lo > r1->_hi ) // Range is always high?
966 return TypeInt::CC_GT;
967
968 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
969 assert(r0->get_con() == r1->get_con(), "must be equal");
970 return TypeInt::CC_EQ; // Equal results.
971 } else if( r0->_hi == r1->_lo ) // Range is never high?
972 return TypeInt::CC_LE;
973 else if( r0->_lo == r1->_hi ) // Range is never low?
974 return TypeInt::CC_GE;
975 return TypeInt::CC; // else use worst case results
976 }
977
978
979 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information.
980 // If both inputs are constants, compare them.
981 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const {
982 assert(!t1->isa_ptr(), "obsolete usage of CmpUL");
983
984 // comparing two unsigned longs
985 const TypeLong* r0 = t1->is_long(); // Handy access
986 const TypeLong* r1 = t2->is_long();
987
988 // Current installed version
989 // Compare ranges for non-overlap
990 julong lo0 = r0->_lo;
991 julong hi0 = r0->_hi;
992 julong lo1 = r1->_lo;
993 julong hi1 = r1->_hi;
994
995 // If either one has both negative and positive values,
996 // it therefore contains both 0 and -1, and since [0..-1] is the
997 // full unsigned range, the type must act as an unsigned bottom.
998 bool bot0 = ((jlong)(lo0 ^ hi0) < 0);
999 bool bot1 = ((jlong)(lo1 ^ hi1) < 0);
1000
1001 if (bot0 || bot1) {
1002 // All unsigned values are LE -1 and GE 0.
1003 if (lo0 == 0 && hi0 == 0) {
1004 return TypeInt::CC_LE; // 0 <= bot
1005 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) {
1006 return TypeInt::CC_GE; // -1 >= bot
1007 } else if (lo1 == 0 && hi1 == 0) {
1008 return TypeInt::CC_GE; // bot >= 0
1009 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) {
1010 return TypeInt::CC_LE; // bot <= -1
1011 }
1012 } else {
1013 // We can use ranges of the form [lo..hi] if signs are the same.
1014 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
1015 // results are reversed, '-' > '+' for unsigned compare
1016 if (hi0 < lo1) {
1017 return TypeInt::CC_LT; // smaller
1018 } else if (lo0 > hi1) {
1019 return TypeInt::CC_GT; // greater
1020 } else if (hi0 == lo1 && lo0 == hi1) {
1021 return TypeInt::CC_EQ; // Equal results
1022 } else if (lo0 >= hi1) {
1023 return TypeInt::CC_GE;
1024 } else if (hi0 <= lo1) {
1025 return TypeInt::CC_LE;
1026 }
1027 }
1028
1029 return TypeInt::CC; // else use worst case results
1030 }
1031
1032 //=============================================================================
1033 //------------------------------sub--------------------------------------------
1034 // Simplify an CmpP (compare 2 pointers) node, based on local information.
1035 // If both inputs are constants, compare them.
1036 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const {
1037 const TypePtr *r0 = t1->is_ptr(); // Handy access
1038 const TypePtr *r1 = t2->is_ptr();
1039
1040 // Undefined inputs makes for an undefined result
1041 if( TypePtr::above_centerline(r0->_ptr) ||
1042 TypePtr::above_centerline(r1->_ptr) )
1043 return Type::TOP;
1044
1045 if (r0 == r1 && r0->singleton()) {
1046 // Equal pointer constants (klasses, nulls, etc.)
1047 return TypeInt::CC_EQ;
1048 }
1049
1050 // See if it is 2 unrelated classes.
1051 const TypeOopPtr* p0 = r0->isa_oopptr();
1052 const TypeOopPtr* p1 = r1->isa_oopptr();
1053 const TypeKlassPtr* k0 = r0->isa_klassptr();
1054 const TypeKlassPtr* k1 = r1->isa_klassptr();
1055 if ((p0 && p1) || (k0 && k1)) {
1056 if (p0 && p1) {
1057 Node* in1 = in(1)->uncast();
1058 Node* in2 = in(2)->uncast();
1059 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1);
1060 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2);
1061 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, nullptr)) {
1062 return TypeInt::CC_GT; // different pointers
1063 }
1064 }
1065 bool xklass0 = p0 ? p0->klass_is_exact() : k0->klass_is_exact();
1066 bool xklass1 = p1 ? p1->klass_is_exact() : k1->klass_is_exact();
1067 bool unrelated_classes = false;
1068
1069 if ((p0 && p0->is_same_java_type_as(p1)) ||
1070 (k0 && k0->is_same_java_type_as(k1))) {
1071 } else if ((p0 && !p1->maybe_java_subtype_of(p0) && !p0->maybe_java_subtype_of(p1)) ||
1072 (k0 && !k1->maybe_java_subtype_of(k0) && !k0->maybe_java_subtype_of(k1))) {
1073 unrelated_classes = true;
1074 } else if ((p0 && !p1->maybe_java_subtype_of(p0)) ||
1075 (k0 && !k1->maybe_java_subtype_of(k0))) {
1076 unrelated_classes = xklass1;
1077 } else if ((p0 && !p0->maybe_java_subtype_of(p1)) ||
1078 (k0 && !k0->maybe_java_subtype_of(k1))) {
1079 unrelated_classes = xklass0;
1080 }
1081 if (!unrelated_classes) {
1082 // Handle inline type arrays
1083 if ((r0->flat_in_array() && r1->not_flat_in_array()) ||
1084 (r1->flat_in_array() && r0->not_flat_in_array())) {
1085 // One type is in flat arrays but the other type is not. Must be unrelated.
1086 unrelated_classes = true;
1087 } else if ((r0->is_not_flat() && r1->is_flat()) ||
1088 (r1->is_not_flat() && r0->is_flat())) {
1089 // One type is a non-flat array and the other type is a flat array. Must be unrelated.
1090 unrelated_classes = true;
1091 } else if ((r0->is_not_null_free() && r1->is_null_free()) ||
1092 (r1->is_not_null_free() && r0->is_null_free())) {
1093 // One type is a nullable array and the other type is a null-free array. Must be unrelated.
1094 unrelated_classes = true;
1095 }
1096 }
1097 if (unrelated_classes) {
1098 // The oops classes are known to be unrelated. If the joined PTRs of
1099 // two oops is not Null and not Bottom, then we are sure that one
1100 // of the two oops is non-null, and the comparison will always fail.
1101 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
1102 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
1103 return TypeInt::CC_GT;
1104 }
1105 }
1106 }
1107
1108 // Known constants can be compared exactly
1109 // Null can be distinguished from any NotNull pointers
1110 // Unknown inputs makes an unknown result
1111 if( r0->singleton() ) {
1112 intptr_t bits0 = r0->get_con();
1113 if( r1->singleton() )
1114 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
1115 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1116 } else if( r1->singleton() ) {
1117 intptr_t bits1 = r1->get_con();
1118 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1119 } else
1120 return TypeInt::CC;
1121 }
1122
1123 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) {
1124 // Return the klass node for (indirect load from OopHandle)
1125 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
1126 // or null if not matching.
1127 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1128 n = bs->step_over_gc_barrier(n);
1129
1130 if (n->Opcode() != Op_LoadP) return nullptr;
1131
1132 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1133 if (!tp || tp->instance_klass() != phase->C->env()->Class_klass()) return nullptr;
1134
1135 Node* adr = n->in(MemNode::Address);
1136 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier.
1137 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return nullptr;
1138 adr = adr->in(MemNode::Address);
1139
1140 intptr_t off = 0;
1141 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off);
1142 if (k == nullptr) return nullptr;
1143 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr();
1144 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return nullptr;
1145
1146 // We've found the klass node of a Java mirror load.
1147 return k;
1148 }
1149
1150 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) {
1151 // for ConP(Foo.class) return ConP(Foo.klass)
1152 // otherwise return null
1153 if (!n->is_Con()) return nullptr;
1154
1155 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1156 if (!tp) return nullptr;
1157
1158 ciType* mirror_type = tp->java_mirror_type();
1159 // TypeInstPtr::java_mirror_type() returns non-null for compile-
1160 // time Class constants only.
1161 if (!mirror_type) return nullptr;
1162
1163 // x.getClass() == int.class can never be true (for all primitive types)
1164 // Return a ConP(null) node for this case.
1165 if (mirror_type->is_classless()) {
1166 return phase->makecon(TypePtr::NULL_PTR);
1167 }
1168
1169 // return the ConP(Foo.klass)
1170 assert(mirror_type->is_klass(), "mirror_type should represent a Klass*");
1171 return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass(), Type::trust_interfaces));
1172 }
1173
1174 //------------------------------Ideal------------------------------------------
1175 // Normalize comparisons between Java mirror loads to compare the klass instead.
1176 //
1177 // Also check for the case of comparing an unknown klass loaded from the primary
1178 // super-type array vs a known klass with no subtypes. This amounts to
1179 // checking to see an unknown klass subtypes a known klass with no subtypes;
1180 // this only happens on an exact match. We can shorten this test by 1 load.
1181 Node* CmpPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1182 // TODO 8284443 in(1) could be cast?
1183 if (in(1)->is_InlineType() && phase->type(in(2))->is_zero_type()) {
1184 // Null checking a scalarized but nullable inline type. Check the null marker
1185 // input instead of the oop input to avoid keeping buffer allocations alive.
1186 return new CmpINode(in(1)->as_InlineType()->get_null_marker(), phase->intcon(0));
1187 }
1188
1189 // Normalize comparisons between Java mirrors into comparisons of the low-
1190 // level klass, where a dependent load could be shortened.
1191 //
1192 // The new pattern has a nice effect of matching the same pattern used in the
1193 // fast path of instanceof/checkcast/Class.isInstance(), which allows
1194 // redundant exact type check be optimized away by GVN.
1195 // For example, in
1196 // if (x.getClass() == Foo.class) {
1197 // Foo foo = (Foo) x;
1198 // // ... use a ...
1199 // }
1200 // a CmpPNode could be shared between if_acmpne and checkcast
1201 {
1202 Node* k1 = isa_java_mirror_load(phase, in(1));
1203 Node* k2 = isa_java_mirror_load(phase, in(2));
1204 Node* conk2 = isa_const_java_mirror(phase, in(2));
1205
1206 // TODO 8366668 add a test for this. Improve this condition
1207 bool doIt = (conk2 && !phase->type(conk2)->isa_aryklassptr());
1208 if (k1 && (k2 || conk2) && doIt) {
1209 Node* lhs = k1;
1210 Node* rhs = (k2 != nullptr) ? k2 : conk2;
1211 set_req_X(1, lhs, phase);
1212 set_req_X(2, rhs, phase);
1213 return this;
1214 }
1215 }
1216
1217 // Constant pointer on right?
1218 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
1219 if (t2 == nullptr || !t2->klass_is_exact())
1220 return nullptr;
1221 // Get the constant klass we are comparing to.
1222 ciKlass* superklass = t2->exact_klass();
1223
1224 // Now check for LoadKlass on left.
1225 Node* ldk1 = in(1);
1226 if (ldk1->is_DecodeNKlass()) {
1227 ldk1 = ldk1->in(1);
1228 if (ldk1->Opcode() != Op_LoadNKlass )
1229 return nullptr;
1230 } else if (ldk1->Opcode() != Op_LoadKlass )
1231 return nullptr;
1232 // Take apart the address of the LoadKlass:
1233 Node* adr1 = ldk1->in(MemNode::Address);
1234 intptr_t con2 = 0;
1235 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
1236 if (ldk2 == nullptr)
1237 return nullptr;
1238 if (con2 == oopDesc::klass_offset_in_bytes()) {
1239 // We are inspecting an object's concrete class.
1240 // Short-circuit the check if the query is abstract.
1241 if (superklass->is_interface() ||
1242 superklass->is_abstract()) {
1243 // Make it come out always false:
1244 this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
1245 return this;
1246 }
1247 }
1248
1249 // Check for a LoadKlass from primary supertype array.
1250 // Any nested loadklass from loadklass+con must be from the p.s. array.
1251 if (ldk2->is_DecodeNKlass()) {
1252 // Keep ldk2 as DecodeN since it could be used in CmpP below.
1253 if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
1254 return nullptr;
1255 } else if (ldk2->Opcode() != Op_LoadKlass)
1256 return nullptr;
1257
1258 // Verify that we understand the situation
1259 if (con2 != (intptr_t) superklass->super_check_offset())
1260 return nullptr; // Might be element-klass loading from array klass
1261
1262 // Do not fold the subtype check to an array klass pointer comparison for null-able inline type arrays
1263 // because null-free [LMyValue <: null-able [LMyValue but the klasses are different. Perform a full test.
1264 if (superklass->is_obj_array_klass() && !superklass->as_array_klass()->is_elem_null_free() &&
1265 superklass->as_array_klass()->element_klass()->is_inlinetype()) {
1266 return nullptr;
1267 }
1268
1269 // If 'superklass' has no subklasses and is not an interface, then we are
1270 // assured that the only input which will pass the type check is
1271 // 'superklass' itself.
1272 //
1273 // We could be more liberal here, and allow the optimization on interfaces
1274 // which have a single implementor. This would require us to increase the
1275 // expressiveness of the add_dependency() mechanism.
1276 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now.
1277
1278 // Object arrays must have their base element have no subtypes
1279 while (superklass->is_obj_array_klass()) {
1280 ciType* elem = superklass->as_obj_array_klass()->element_type();
1281 superklass = elem->as_klass();
1282 }
1283 if (superklass->is_instance_klass()) {
1284 ciInstanceKlass* ik = superklass->as_instance_klass();
1285 if (ik->has_subklass() || ik->is_interface()) return nullptr;
1286 // Add a dependency if there is a chance that a subclass will be added later.
1287 if (!ik->is_final()) {
1288 phase->C->dependencies()->assert_leaf_type(ik);
1289 }
1290 }
1291
1292 // Bypass the dependent load, and compare directly
1293 this->set_req_X(1, ldk2, phase);
1294
1295 return this;
1296 }
1297
1298 //=============================================================================
1299 //------------------------------sub--------------------------------------------
1300 // Simplify an CmpN (compare 2 pointers) node, based on local information.
1301 // If both inputs are constants, compare them.
1302 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
1303 ShouldNotReachHere();
1304 return bottom_type();
1305 }
1306
1307 //------------------------------Ideal------------------------------------------
1308 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1309 return nullptr;
1310 }
1311
1312 //=============================================================================
1313 //------------------------------Value------------------------------------------
1314 // Simplify an CmpF (compare 2 floats ) node, based on local information.
1315 // If both inputs are constants, compare them.
1316 const Type* CmpFNode::Value(PhaseGVN* phase) const {
1317 const Node* in1 = in(1);
1318 const Node* in2 = in(2);
1319 // Either input is TOP ==> the result is TOP
1320 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1321 if( t1 == Type::TOP ) return Type::TOP;
1322 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1323 if( t2 == Type::TOP ) return Type::TOP;
1324
1325 // Not constants? Don't know squat - even if they are the same
1326 // value! If they are NaN's they compare to LT instead of EQ.
1327 const TypeF *tf1 = t1->isa_float_constant();
1328 const TypeF *tf2 = t2->isa_float_constant();
1329 if( !tf1 || !tf2 ) return TypeInt::CC;
1330
1331 // This implements the Java bytecode fcmpl, so unordered returns -1.
1332 if( tf1->is_nan() || tf2->is_nan() )
1333 return TypeInt::CC_LT;
1334
1335 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
1336 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
1337 assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
1338 return TypeInt::CC_EQ;
1339 }
1340
1341
1342 //=============================================================================
1343 //------------------------------Value------------------------------------------
1344 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
1345 // If both inputs are constants, compare them.
1346 const Type* CmpDNode::Value(PhaseGVN* phase) const {
1347 const Node* in1 = in(1);
1348 const Node* in2 = in(2);
1349 // Either input is TOP ==> the result is TOP
1350 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1351 if( t1 == Type::TOP ) return Type::TOP;
1352 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1353 if( t2 == Type::TOP ) return Type::TOP;
1354
1355 // Not constants? Don't know squat - even if they are the same
1356 // value! If they are NaN's they compare to LT instead of EQ.
1357 const TypeD *td1 = t1->isa_double_constant();
1358 const TypeD *td2 = t2->isa_double_constant();
1359 if( !td1 || !td2 ) return TypeInt::CC;
1360
1361 // This implements the Java bytecode dcmpl, so unordered returns -1.
1362 if( td1->is_nan() || td2->is_nan() )
1363 return TypeInt::CC_LT;
1364
1365 if( td1->_d < td2->_d ) return TypeInt::CC_LT;
1366 if( td1->_d > td2->_d ) return TypeInt::CC_GT;
1367 assert( td1->_d == td2->_d, "do not understand FP behavior" );
1368 return TypeInt::CC_EQ;
1369 }
1370
1371 //------------------------------Ideal------------------------------------------
1372 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
1373 // Check if we can change this to a CmpF and remove a ConvD2F operation.
1374 // Change (CMPD (F2D (float)) (ConD value))
1375 // To (CMPF (float) (ConF value))
1376 // Valid when 'value' does not lose precision as a float.
1377 // Benefits: eliminates conversion, does not require 24-bit mode
1378
1379 // NaNs prevent commuting operands. This transform works regardless of the
1380 // order of ConD and ConvF2D inputs by preserving the original order.
1381 int idx_f2d = 1; // ConvF2D on left side?
1382 if( in(idx_f2d)->Opcode() != Op_ConvF2D )
1383 idx_f2d = 2; // No, swap to check for reversed args
1384 int idx_con = 3-idx_f2d; // Check for the constant on other input
1385
1386 if( ConvertCmpD2CmpF &&
1387 in(idx_f2d)->Opcode() == Op_ConvF2D &&
1388 in(idx_con)->Opcode() == Op_ConD ) {
1389 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
1390 double t2_value_as_double = t2->_d;
1391 float t2_value_as_float = (float)t2_value_as_double;
1392 if( t2_value_as_double == (double)t2_value_as_float ) {
1393 // Test value can be represented as a float
1394 // Eliminate the conversion to double and create new comparison
1395 Node *new_in1 = in(idx_f2d)->in(1);
1396 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
1397 if( idx_f2d != 1 ) { // Must flip args to match original order
1398 Node *tmp = new_in1;
1399 new_in1 = new_in2;
1400 new_in2 = tmp;
1401 }
1402 CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
1403 ? new CmpF3Node( new_in1, new_in2 )
1404 : new CmpFNode ( new_in1, new_in2 ) ;
1405 return new_cmp; // Changed to CmpFNode
1406 }
1407 // Testing value required the precision of a double
1408 }
1409 return nullptr; // No change
1410 }
1411
1412 //=============================================================================
1413 //------------------------------Value------------------------------------------
1414 const Type* FlatArrayCheckNode::Value(PhaseGVN* phase) const {
1415 bool all_not_flat = true;
1416 for (uint i = ArrayOrKlass; i < req(); ++i) {
1417 const Type* t = phase->type(in(i));
1418 if (t == Type::TOP) {
1419 return Type::TOP;
1420 }
1421 if (t->is_ptr()->is_flat()) {
1422 // One of the input arrays is flat, check always passes
1423 return TypeInt::CC_EQ;
1424 } else if (!t->is_ptr()->is_not_flat()) {
1425 // One of the input arrays might be flat
1426 all_not_flat = false;
1427 }
1428 }
1429 if (all_not_flat) {
1430 // None of the input arrays can be flat, check always fails
1431 return TypeInt::CC_GT;
1432 }
1433 return TypeInt::CC;
1434 }
1435
1436 //------------------------------Ideal------------------------------------------
1437 Node* FlatArrayCheckNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1438 bool changed = false;
1439 // Remove inputs that are known to be non-flat
1440 for (uint i = ArrayOrKlass; i < req(); ++i) {
1441 const Type* t = phase->type(in(i));
1442 if (t->isa_ptr() && t->is_ptr()->is_not_flat()) {
1443 del_req(i--);
1444 changed = true;
1445 }
1446 }
1447 return changed ? this : nullptr;
1448 }
1449
1450 //=============================================================================
1451 //------------------------------cc2logical-------------------------------------
1452 // Convert a condition code type to a logical type
1453 const Type *BoolTest::cc2logical( const Type *CC ) const {
1454 if( CC == Type::TOP ) return Type::TOP;
1455 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
1456 const TypeInt *ti = CC->is_int();
1457 if( ti->is_con() ) { // Only 1 kind of condition codes set?
1458 // Match low order 2 bits
1459 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
1460 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result
1461 return TypeInt::make(tmp); // Boolean result
1462 }
1463
1464 if( CC == TypeInt::CC_GE ) {
1465 if( _test == ge ) return TypeInt::ONE;
1466 if( _test == lt ) return TypeInt::ZERO;
1467 }
1468 if( CC == TypeInt::CC_LE ) {
1469 if( _test == le ) return TypeInt::ONE;
1470 if( _test == gt ) return TypeInt::ZERO;
1471 }
1472
1473 return TypeInt::BOOL;
1474 }
1475
1476 //------------------------------dump_spec-------------------------------------
1477 // Print special per-node info
1478 void BoolTest::dump_on(outputStream *st) const {
1479 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"};
1480 st->print("%s", msg[_test]);
1481 }
1482
1483 // Returns the logical AND of two tests (or 'never' if both tests can never be true).
1484 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'.
1485 BoolTest::mask BoolTest::merge(BoolTest other) const {
1486 const mask res[illegal+1][illegal+1] = {
1487 // eq, gt, of, lt, ne, le, nof, ge, never, illegal
1488 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq
1489 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt
1490 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of
1491 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt
1492 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne
1493 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le
1494 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof
1495 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge
1496 {never, never, never, never, never, never, never, never, never, illegal}, // never
1497 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal
1498 return res[_test][other._test];
1499 }
1500
1501 //=============================================================================
1502 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
1503 uint BoolNode::size_of() const { return sizeof(BoolNode); }
1504
1505 //------------------------------operator==-------------------------------------
1506 bool BoolNode::cmp( const Node &n ) const {
1507 const BoolNode *b = (const BoolNode *)&n; // Cast up
1508 return (_test._test == b->_test._test);
1509 }
1510
1511 //-------------------------------make_predicate--------------------------------
1512 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1513 if (test_value->is_Con()) return test_value;
1514 if (test_value->is_Bool()) return test_value;
1515 if (test_value->is_CMove() &&
1516 test_value->in(CMoveNode::Condition)->is_Bool()) {
1517 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool();
1518 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1519 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1520 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1521 return bol;
1522 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1523 return phase->transform( bol->negate(phase) );
1524 }
1525 // Else fall through. The CMove gets in the way of the test.
1526 // It should be the case that make_predicate(bol->as_int_value()) == bol.
1527 }
1528 Node* cmp = new CmpINode(test_value, phase->intcon(0));
1529 cmp = phase->transform(cmp);
1530 Node* bol = new BoolNode(cmp, BoolTest::ne);
1531 return phase->transform(bol);
1532 }
1533
1534 //--------------------------------as_int_value---------------------------------
1535 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1536 // Inverse to make_predicate. The CMove probably boils down to a Conv2B.
1537 Node* cmov = CMoveNode::make(this, phase->intcon(0), phase->intcon(1), TypeInt::BOOL);
1538 return phase->transform(cmov);
1539 }
1540
1541 //----------------------------------negate-------------------------------------
1542 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1543 return new BoolNode(in(1), _test.negate());
1544 }
1545
1546 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub
1547 // overflows and we can prove that C is not in the two resulting ranges.
1548 // This optimization is similar to the one performed by CmpUNode::Value().
1549 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op,
1550 int cmp1_op, const TypeInt* cmp2_type) {
1551 // Only optimize eq/ne integer comparison of add/sub
1552 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1553 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) {
1554 // Skip cases were inputs of add/sub are not integers or of bottom type
1555 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int();
1556 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int();
1557 if ((r0 != nullptr) && (r0 != TypeInt::INT) &&
1558 (r1 != nullptr) && (r1 != TypeInt::INT) &&
1559 (cmp2_type != TypeInt::INT)) {
1560 // Compute exact (long) type range of add/sub result
1561 jlong lo_long = r0->_lo;
1562 jlong hi_long = r0->_hi;
1563 if (cmp1_op == Op_AddI) {
1564 lo_long += r1->_lo;
1565 hi_long += r1->_hi;
1566 } else {
1567 lo_long -= r1->_hi;
1568 hi_long -= r1->_lo;
1569 }
1570 // Check for over-/underflow by casting to integer
1571 int lo_int = (int)lo_long;
1572 int hi_int = (int)hi_long;
1573 bool underflow = lo_long != (jlong)lo_int;
1574 bool overflow = hi_long != (jlong)hi_int;
1575 if ((underflow != overflow) && (hi_int < lo_int)) {
1576 // Overflow on one boundary, compute resulting type ranges:
1577 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT]
1578 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
1579 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w);
1580 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w);
1581 // Compare second input of cmp to both type ranges
1582 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type);
1583 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type);
1584 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) {
1585 // The result of the add/sub will never equal cmp2. Replace BoolNode
1586 // by false (0) if it tests for equality and by true (1) otherwise.
1587 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1);
1588 }
1589 }
1590 }
1591 }
1592 return nullptr;
1593 }
1594
1595 static bool is_counted_loop_cmp(Node *cmp) {
1596 Node *n = cmp->in(1)->in(1);
1597 return n != nullptr &&
1598 n->is_Phi() &&
1599 n->in(0) != nullptr &&
1600 n->in(0)->is_CountedLoop() &&
1601 n->in(0)->as_CountedLoop()->phi() == n;
1602 }
1603
1604 //------------------------------Ideal------------------------------------------
1605 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1606 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1607 // This moves the constant to the right. Helps value-numbering.
1608 Node *cmp = in(1);
1609 if( !cmp->is_Sub() ) return nullptr;
1610 int cop = cmp->Opcode();
1611 if( cop == Op_FastLock || cop == Op_FastUnlock ||
1612 cmp->is_SubTypeCheck() || cop == Op_VectorTest ) {
1613 return nullptr;
1614 }
1615 Node *cmp1 = cmp->in(1);
1616 Node *cmp2 = cmp->in(2);
1617 if( !cmp1 ) return nullptr;
1618
1619 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) {
1620 return nullptr;
1621 }
1622
1623 const int cmp1_op = cmp1->Opcode();
1624 const int cmp2_op = cmp2->Opcode();
1625
1626 // Constant on left?
1627 Node *con = cmp1;
1628 // Move constants to the right of compare's to canonicalize.
1629 // Do not muck with Opaque1 nodes, as this indicates a loop
1630 // guard that cannot change shape.
1631 if (con->is_Con() && !cmp2->is_Con() && cmp2_op != Op_OpaqueZeroTripGuard &&
1632 // Because of NaN's, CmpD and CmpF are not commutative
1633 cop != Op_CmpD && cop != Op_CmpF &&
1634 // Protect against swapping inputs to a compare when it is used by a
1635 // counted loop exit, which requires maintaining the loop-limit as in(2)
1636 !is_counted_loop_exit_test() ) {
1637 // Ok, commute the constant to the right of the cmp node.
1638 // Clone the Node, getting a new Node of the same class
1639 cmp = cmp->clone();
1640 // Swap inputs to the clone
1641 cmp->swap_edges(1, 2);
1642 cmp = phase->transform( cmp );
1643 return new BoolNode( cmp, _test.commute() );
1644 }
1645
1646 // Change "bool eq/ne (cmp (cmove (bool tst (cmp2)) 1 0) 0)" into "bool tst/~tst (cmp2)"
1647 if (cop == Op_CmpI &&
1648 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1649 cmp1_op == Op_CMoveI && cmp2->find_int_con(1) == 0) {
1650 // 0 should be on the true branch
1651 if (cmp1->in(CMoveNode::Condition)->is_Bool() &&
1652 cmp1->in(CMoveNode::IfTrue)->find_int_con(1) == 0 &&
1653 cmp1->in(CMoveNode::IfFalse)->find_int_con(0) != 0) {
1654 BoolNode* target = cmp1->in(CMoveNode::Condition)->as_Bool();
1655 return new BoolNode(target->in(1),
1656 (_test._test == BoolTest::eq) ? target->_test._test :
1657 target->_test.negate());
1658 }
1659 }
1660
1661 // Change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1662 if (cop == Op_CmpI &&
1663 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1664 cmp1_op == Op_AndI && cmp2_op == Op_ConI &&
1665 cmp1->in(2)->Opcode() == Op_ConI) {
1666 const TypeInt *t12 = phase->type(cmp2)->isa_int();
1667 const TypeInt *t112 = phase->type(cmp1->in(2))->isa_int();
1668 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1669 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1670 Node *ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1671 return new BoolNode(ncmp, _test.negate());
1672 }
1673 }
1674
1675 // Same for long type: change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1676 if (cop == Op_CmpL &&
1677 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1678 cmp1_op == Op_AndL && cmp2_op == Op_ConL &&
1679 cmp1->in(2)->Opcode() == Op_ConL) {
1680 const TypeLong *t12 = phase->type(cmp2)->isa_long();
1681 const TypeLong *t112 = phase->type(cmp1->in(2))->isa_long();
1682 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1683 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1684 Node *ncmp = phase->transform(new CmpLNode(cmp1, phase->longcon(0)));
1685 return new BoolNode(ncmp, _test.negate());
1686 }
1687 }
1688
1689 // Change "cmp (add X min_jint) (add Y min_jint)" into "cmpu X Y"
1690 // and "cmp (add X min_jint) c" into "cmpu X (c + min_jint)"
1691 if (cop == Op_CmpI &&
1692 cmp1_op == Op_AddI &&
1693 phase->type(cmp1->in(2)) == TypeInt::MIN &&
1694 !is_cloop_condition(this)) {
1695 if (cmp2_op == Op_ConI) {
1696 Node* ncmp2 = phase->intcon(java_add(cmp2->get_int(), min_jint));
1697 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), ncmp2));
1698 return new BoolNode(ncmp, _test._test);
1699 } else if (cmp2_op == Op_AddI &&
1700 phase->type(cmp2->in(2)) == TypeInt::MIN &&
1701 !is_cloop_condition(this)) {
1702 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), cmp2->in(1)));
1703 return new BoolNode(ncmp, _test._test);
1704 }
1705 }
1706
1707 // Change "cmp (add X min_jlong) (add Y min_jlong)" into "cmpu X Y"
1708 // and "cmp (add X min_jlong) c" into "cmpu X (c + min_jlong)"
1709 if (cop == Op_CmpL &&
1710 cmp1_op == Op_AddL &&
1711 phase->type(cmp1->in(2)) == TypeLong::MIN &&
1712 !is_cloop_condition(this)) {
1713 if (cmp2_op == Op_ConL) {
1714 Node* ncmp2 = phase->longcon(java_add(cmp2->get_long(), min_jlong));
1715 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), ncmp2));
1716 return new BoolNode(ncmp, _test._test);
1717 } else if (cmp2_op == Op_AddL &&
1718 phase->type(cmp2->in(2)) == TypeLong::MIN &&
1719 !is_cloop_condition(this)) {
1720 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), cmp2->in(1)));
1721 return new BoolNode(ncmp, _test._test);
1722 }
1723 }
1724
1725 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1726 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the
1727 // test instead.
1728 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1729 if (cmp2_type == nullptr) return nullptr;
1730 Node* j_xor = cmp1;
1731 if( cmp2_type == TypeInt::ZERO &&
1732 cmp1_op == Op_XorI &&
1733 j_xor->in(1) != j_xor && // An xor of itself is dead
1734 phase->type( j_xor->in(1) ) == TypeInt::BOOL &&
1735 phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1736 (_test._test == BoolTest::eq ||
1737 _test._test == BoolTest::ne) ) {
1738 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2));
1739 return new BoolNode( ncmp, _test.negate() );
1740 }
1741
1742 // Transform: "((x & (m - 1)) <u m)" or "(((m - 1) & x) <u m)" into "(m >u 0)"
1743 // This is case [CMPU_MASK] which is further described at the method comment of BoolNode::Value_cmpu_and_mask().
1744 if (cop == Op_CmpU && _test._test == BoolTest::lt && cmp1_op == Op_AndI) {
1745 Node* m = cmp2; // RHS: m
1746 for (int add_idx = 1; add_idx <= 2; add_idx++) { // LHS: "(m + (-1)) & x" or "x & (m + (-1))"?
1747 Node* maybe_m_minus_1 = cmp1->in(add_idx);
1748 if (maybe_m_minus_1->Opcode() == Op_AddI &&
1749 maybe_m_minus_1->in(2)->find_int_con(0) == -1 &&
1750 maybe_m_minus_1->in(1) == m) {
1751 Node* m_cmpu_0 = phase->transform(new CmpUNode(m, phase->intcon(0)));
1752 return new BoolNode(m_cmpu_0, BoolTest::gt);
1753 }
1754 }
1755 }
1756
1757 // Change x u< 1 or x u<= 0 to x == 0
1758 // and x u> 0 or u>= 1 to x != 0
1759 if (cop == Op_CmpU &&
1760 cmp1_op != Op_LoadRange &&
1761 (((_test._test == BoolTest::lt || _test._test == BoolTest::ge) &&
1762 cmp2->find_int_con(-1) == 1) ||
1763 ((_test._test == BoolTest::le || _test._test == BoolTest::gt) &&
1764 cmp2->find_int_con(-1) == 0))) {
1765 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1766 return new BoolNode(ncmp, _test.is_less() ? BoolTest::eq : BoolTest::ne);
1767 }
1768
1769 // Change (arraylength <= 0) or (arraylength == 0)
1770 // into (arraylength u<= 0)
1771 // Also change (arraylength != 0) into (arraylength u> 0)
1772 // The latter version matches the code pattern generated for
1773 // array range checks, which will more likely be optimized later.
1774 if (cop == Op_CmpI &&
1775 cmp1_op == Op_LoadRange &&
1776 cmp2->find_int_con(-1) == 0) {
1777 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) {
1778 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1779 return new BoolNode(ncmp, BoolTest::le);
1780 } else if (_test._test == BoolTest::ne) {
1781 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1782 return new BoolNode(ncmp, BoolTest::gt);
1783 }
1784 }
1785
1786 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1787 // This is a standard idiom for branching on a boolean value.
1788 Node *c2b = cmp1;
1789 if( cmp2_type == TypeInt::ZERO &&
1790 cmp1_op == Op_Conv2B &&
1791 (_test._test == BoolTest::eq ||
1792 _test._test == BoolTest::ne) ) {
1793 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1794 ? (Node*)new CmpINode(c2b->in(1),cmp2)
1795 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1796 );
1797 return new BoolNode( ncmp, _test._test );
1798 }
1799
1800 // Comparing a SubI against a zero is equal to comparing the SubI
1801 // arguments directly. This only works for eq and ne comparisons
1802 // due to possible integer overflow.
1803 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1804 (cop == Op_CmpI) &&
1805 (cmp1_op == Op_SubI) &&
1806 ( cmp2_type == TypeInt::ZERO ) ) {
1807 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2)));
1808 return new BoolNode( ncmp, _test._test );
1809 }
1810
1811 // Same as above but with and AddI of a constant
1812 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1813 cop == Op_CmpI &&
1814 cmp1_op == Op_AddI &&
1815 cmp1->in(2) != nullptr &&
1816 phase->type(cmp1->in(2))->isa_int() &&
1817 phase->type(cmp1->in(2))->is_int()->is_con() &&
1818 cmp2_type == TypeInt::ZERO &&
1819 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape
1820 ) {
1821 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int();
1822 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi)));
1823 return new BoolNode( ncmp, _test._test );
1824 }
1825
1826 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)"
1827 // since zero check of conditional negation of an integer is equal to
1828 // zero check of the integer directly.
1829 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1830 (cop == Op_CmpI) &&
1831 (cmp2_type == TypeInt::ZERO) &&
1832 (cmp1_op == Op_Phi)) {
1833 // There should be a diamond phi with true path at index 1 or 2
1834 PhiNode *phi = cmp1->as_Phi();
1835 int idx_true = phi->is_diamond_phi();
1836 if (idx_true != 0) {
1837 // True input is in(idx_true) while false input is in(3 - idx_true)
1838 Node *tin = phi->in(idx_true);
1839 Node *fin = phi->in(3 - idx_true);
1840 if ((tin->Opcode() == Op_SubI) &&
1841 (phase->type(tin->in(1)) == TypeInt::ZERO) &&
1842 (tin->in(2) == fin)) {
1843 // Found conditional negation at true path, create a new CmpINode without that
1844 Node *ncmp = phase->transform(new CmpINode(fin, cmp2));
1845 return new BoolNode(ncmp, _test._test);
1846 }
1847 if ((fin->Opcode() == Op_SubI) &&
1848 (phase->type(fin->in(1)) == TypeInt::ZERO) &&
1849 (fin->in(2) == tin)) {
1850 // Found conditional negation at false path, create a new CmpINode without that
1851 Node *ncmp = phase->transform(new CmpINode(tin, cmp2));
1852 return new BoolNode(ncmp, _test._test);
1853 }
1854 }
1855 }
1856
1857 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the
1858 // most general case because negating 0x80000000 does nothing. Needed for
1859 // the CmpF3/SubI/CmpI idiom.
1860 if( cop == Op_CmpI &&
1861 cmp1_op == Op_SubI &&
1862 cmp2_type == TypeInt::ZERO &&
1863 phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1864 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1865 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2));
1866 return new BoolNode( ncmp, _test.commute() );
1867 }
1868
1869 // Try to optimize signed integer comparison
1870 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type);
1871
1872 // The transformation below is not valid for either signed or unsigned
1873 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1874 // This transformation can be resurrected when we are able to
1875 // make inferences about the range of values being subtracted from
1876 // (or added to) relative to the wraparound point.
1877 //
1878 // // Remove +/-1's if possible.
1879 // // "X <= Y-1" becomes "X < Y"
1880 // // "X+1 <= Y" becomes "X < Y"
1881 // // "X < Y+1" becomes "X <= Y"
1882 // // "X-1 < Y" becomes "X <= Y"
1883 // // Do not this to compares off of the counted-loop-end. These guys are
1884 // // checking the trip counter and they want to use the post-incremented
1885 // // counter. If they use the PRE-incremented counter, then the counter has
1886 // // to be incremented in a private block on a loop backedge.
1887 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1888 // return nullptr;
1889 // #ifndef PRODUCT
1890 // // Do not do this in a wash GVN pass during verification.
1891 // // Gets triggered by too many simple optimizations to be bothered with
1892 // // re-trying it again and again.
1893 // if( !phase->allow_progress() ) return nullptr;
1894 // #endif
1895 // // Not valid for unsigned compare because of corner cases in involving zero.
1896 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1897 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1898 // // "0 <=u Y" is always true).
1899 // if( cmp->Opcode() == Op_CmpU ) return nullptr;
1900 // int cmp2_op = cmp2->Opcode();
1901 // if( _test._test == BoolTest::le ) {
1902 // if( cmp1_op == Op_AddI &&
1903 // phase->type( cmp1->in(2) ) == TypeInt::ONE )
1904 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1905 // else if( cmp2_op == Op_AddI &&
1906 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1907 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1908 // } else if( _test._test == BoolTest::lt ) {
1909 // if( cmp1_op == Op_AddI &&
1910 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1911 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1912 // else if( cmp2_op == Op_AddI &&
1913 // phase->type( cmp2->in(2) ) == TypeInt::ONE )
1914 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1915 // }
1916 }
1917
1918 // We use the following Lemmas/insights for the following two transformations (1) and (2):
1919 // x & y <=u y, for any x and y (Lemma 1, masking always results in a smaller unsigned number)
1920 // y <u y + 1 is always true if y != -1 (Lemma 2, (uint)(-1 + 1) == (uint)(UINT_MAX + 1) which overflows)
1921 // y <u 0 is always false for any y (Lemma 3, 0 == UINT_MIN and nothing can be smaller than that)
1922 //
1923 // (1a) Always: Change ((x & m) <=u m ) or ((m & x) <=u m ) to always true (true by Lemma 1)
1924 // (1b) If m != -1: Change ((x & m) <u m + 1) or ((m & x) <u m + 1) to always true:
1925 // x & m <=u m is always true // (Lemma 1)
1926 // x & m <=u m <u m + 1 is always true // (Lemma 2: m <u m + 1, if m != -1)
1927 //
1928 // A counter example for (1b), if we allowed m == -1:
1929 // (x & m) <u m + 1
1930 // (x & -1) <u 0
1931 // x <u 0
1932 // which is false for any x (Lemma 3)
1933 //
1934 // (2) Change ((x & (m - 1)) <u m) or (((m - 1) & x) <u m) to (m >u 0)
1935 // This is the off-by-one variant of the above.
1936 //
1937 // We now prove that this replacement is correct. This is the same as proving
1938 // "m >u 0" if and only if "x & (m - 1) <u m", i.e. "m >u 0 <=> x & (m - 1) <u m"
1939 //
1940 // We use (Lemma 1) and (Lemma 3) from above.
1941 //
1942 // Case "x & (m - 1) <u m => m >u 0":
1943 // We prove this by contradiction:
1944 // Assume m <=u 0 which is equivalent to m == 0:
1945 // and thus
1946 // x & (m - 1) <u m = 0 // m == 0
1947 // y <u 0 // y = x & (m - 1)
1948 // by Lemma 3, this is always false, i.e. a contradiction to our assumption.
1949 //
1950 // Case "m >u 0 => x & (m - 1) <u m":
1951 // x & (m - 1) <=u (m - 1) // (Lemma 1)
1952 // x & (m - 1) <=u (m - 1) <u m // Using assumption m >u 0, no underflow of "m - 1"
1953 //
1954 //
1955 // Note that the signed version of "m > 0":
1956 // m > 0 <=> x & (m - 1) <u m
1957 // does not hold:
1958 // Assume m == -1 and x == -1:
1959 // x & (m - 1) <u m
1960 // -1 & -2 <u -1
1961 // -2 <u -1
1962 // UINT_MAX - 1 <u UINT_MAX // Signed to unsigned numbers
1963 // which is true while
1964 // m > 0
1965 // is false which is a contradiction.
1966 //
1967 // (1a) and (1b) is covered by this method since we can directly return a true value as type while (2) is covered
1968 // in BoolNode::Ideal since we create a new non-constant node (see [CMPU_MASK]).
1969 const Type* BoolNode::Value_cmpu_and_mask(PhaseValues* phase) const {
1970 Node* cmp = in(1);
1971 if (cmp != nullptr && cmp->Opcode() == Op_CmpU) {
1972 Node* cmp1 = cmp->in(1);
1973 Node* cmp2 = cmp->in(2);
1974
1975 if (cmp1->Opcode() == Op_AndI) {
1976 Node* m = nullptr;
1977 if (_test._test == BoolTest::le) {
1978 // (1a) "((x & m) <=u m)", cmp2 = m
1979 m = cmp2;
1980 } else if (_test._test == BoolTest::lt && cmp2->Opcode() == Op_AddI && cmp2->in(2)->find_int_con(0) == 1) {
1981 // (1b) "(x & m) <u m + 1" and "(m & x) <u m + 1", cmp2 = m + 1
1982 Node* rhs_m = cmp2->in(1);
1983 const TypeInt* rhs_m_type = phase->type(rhs_m)->isa_int();
1984 if (rhs_m_type->_lo > -1 || rhs_m_type->_hi < -1) {
1985 // Exclude any case where m == -1 is possible.
1986 m = rhs_m;
1987 }
1988 }
1989
1990 if (cmp1->in(2) == m || cmp1->in(1) == m) {
1991 return TypeInt::ONE;
1992 }
1993 }
1994 }
1995
1996 return nullptr;
1997 }
1998
1999 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
2000 // based on local information. If the input is constant, do it.
2001 const Type* BoolNode::Value(PhaseGVN* phase) const {
2002 const Type* t = Value_cmpu_and_mask(phase);
2003 if (t != nullptr) {
2004 return t;
2005 }
2006
2007 return _test.cc2logical( phase->type( in(1) ) );
2008 }
2009
2010 #ifndef PRODUCT
2011 //------------------------------dump_spec--------------------------------------
2012 // Dump special per-node info
2013 void BoolNode::dump_spec(outputStream *st) const {
2014 st->print("[");
2015 _test.dump_on(st);
2016 st->print("]");
2017 }
2018 #endif
2019
2020 //----------------------is_counted_loop_exit_test------------------------------
2021 // Returns true if node is used by a counted loop node.
2022 bool BoolNode::is_counted_loop_exit_test() {
2023 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
2024 Node* use = fast_out(i);
2025 if (use->is_CountedLoopEnd()) {
2026 return true;
2027 }
2028 }
2029 return false;
2030 }
2031
2032 //=============================================================================
2033 //------------------------------Value------------------------------------------
2034 const Type* AbsNode::Value(PhaseGVN* phase) const {
2035 const Type* t1 = phase->type(in(1));
2036 if (t1 == Type::TOP) return Type::TOP;
2037
2038 switch (t1->base()) {
2039 case Type::Int: {
2040 const TypeInt* ti = t1->is_int();
2041 if (ti->is_con()) {
2042 return TypeInt::make(g_uabs(ti->get_con()));
2043 }
2044 break;
2045 }
2046 case Type::Long: {
2047 const TypeLong* tl = t1->is_long();
2048 if (tl->is_con()) {
2049 return TypeLong::make(g_uabs(tl->get_con()));
2050 }
2051 break;
2052 }
2053 case Type::FloatCon:
2054 return TypeF::make(abs(t1->getf()));
2055 case Type::DoubleCon:
2056 return TypeD::make(abs(t1->getd()));
2057 default:
2058 break;
2059 }
2060
2061 return bottom_type();
2062 }
2063
2064 //------------------------------Identity----------------------------------------
2065 Node* AbsNode::Identity(PhaseGVN* phase) {
2066 Node* in1 = in(1);
2067 // No need to do abs for non-negative values
2068 if (phase->type(in1)->higher_equal(TypeInt::POS) ||
2069 phase->type(in1)->higher_equal(TypeLong::POS)) {
2070 return in1;
2071 }
2072 // Convert "abs(abs(x))" into "abs(x)"
2073 if (in1->Opcode() == Opcode()) {
2074 return in1;
2075 }
2076 return this;
2077 }
2078
2079 //------------------------------Ideal------------------------------------------
2080 Node* AbsNode::Ideal(PhaseGVN* phase, bool can_reshape) {
2081 Node* in1 = in(1);
2082 // Convert "abs(0-x)" into "abs(x)"
2083 if (in1->is_Sub() && phase->type(in1->in(1))->is_zero_type()) {
2084 set_req_X(1, in1->in(2), phase);
2085 return this;
2086 }
2087 return nullptr;
2088 }
2089
2090 //=============================================================================
2091 //------------------------------Value------------------------------------------
2092 // Compute sqrt
2093 const Type* SqrtDNode::Value(PhaseGVN* phase) const {
2094 const Type *t1 = phase->type( in(1) );
2095 if( t1 == Type::TOP ) return Type::TOP;
2096 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
2097 double d = t1->getd();
2098 if( d < 0.0 ) return Type::DOUBLE;
2099 return TypeD::make( sqrt( d ) );
2100 }
2101
2102 const Type* SqrtFNode::Value(PhaseGVN* phase) const {
2103 const Type *t1 = phase->type( in(1) );
2104 if( t1 == Type::TOP ) return Type::TOP;
2105 if( t1->base() != Type::FloatCon ) return Type::FLOAT;
2106 float f = t1->getf();
2107 if( f < 0.0f ) return Type::FLOAT;
2108 return TypeF::make( (float)sqrt( (double)f ) );
2109 }
2110
2111 const Type* SqrtHFNode::Value(PhaseGVN* phase) const {
2112 const Type* t1 = phase->type(in(1));
2113 if (t1 == Type::TOP) { return Type::TOP; }
2114 if (t1->base() != Type::HalfFloatCon) { return Type::HALF_FLOAT; }
2115 float f = t1->getf();
2116 if (f < 0.0f) return Type::HALF_FLOAT;
2117 return TypeH::make((float)sqrt((double)f));
2118 }
2119
2120 static const Type* reverse_bytes(int opcode, const Type* con) {
2121 switch (opcode) {
2122 case Op_ReverseBytesS: return TypeInt::make(byteswap(checked_cast<jshort>(con->is_int()->get_con())));
2123 case Op_ReverseBytesUS: return TypeInt::make(byteswap(checked_cast<jchar>(con->is_int()->get_con())));
2124 case Op_ReverseBytesI: return TypeInt::make(byteswap(checked_cast<jint>(con->is_int()->get_con())));
2125 case Op_ReverseBytesL: return TypeLong::make(byteswap(checked_cast<jlong>(con->is_long()->get_con())));
2126 default: ShouldNotReachHere();
2127 }
2128 }
2129
2130 const Type* ReverseBytesNode::Value(PhaseGVN* phase) const {
2131 const Type* type = phase->type(in(1));
2132 if (type == Type::TOP) {
2133 return Type::TOP;
2134 }
2135 if (type->singleton()) {
2136 return reverse_bytes(Opcode(), type);
2137 }
2138 return bottom_type();
2139 }
2140
2141 const Type* ReverseINode::Value(PhaseGVN* phase) const {
2142 const Type *t1 = phase->type( in(1) );
2143 if (t1 == Type::TOP) {
2144 return Type::TOP;
2145 }
2146 const TypeInt* t1int = t1->isa_int();
2147 if (t1int && t1int->is_con()) {
2148 jint res = reverse_bits(t1int->get_con());
2149 return TypeInt::make(res);
2150 }
2151 return bottom_type();
2152 }
2153
2154 const Type* ReverseLNode::Value(PhaseGVN* phase) const {
2155 const Type *t1 = phase->type( in(1) );
2156 if (t1 == Type::TOP) {
2157 return Type::TOP;
2158 }
2159 const TypeLong* t1long = t1->isa_long();
2160 if (t1long && t1long->is_con()) {
2161 jlong res = reverse_bits(t1long->get_con());
2162 return TypeLong::make(res);
2163 }
2164 return bottom_type();
2165 }
2166
2167 Node* InvolutionNode::Identity(PhaseGVN* phase) {
2168 // Op ( Op x ) => x
2169 if (in(1)->Opcode() == Opcode()) {
2170 return in(1)->in(1);
2171 }
2172 return this;
2173 }