1 /*
2 * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.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/cfgnode.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 // Remove double negation
58 const Type *zero = add_id();
59 if( phase->type( in(1) )->higher_equal( zero ) &&
60 in(2)->Opcode() == Opcode() &&
61 phase->type( in(2)->in(1) )->higher_equal( zero ) ) {
62 return in(2)->in(2);
63 }
64
65 // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y
66 if (in(1)->Opcode() == Op_AddI || in(1)->Opcode() == Op_AddL) {
67 if (in(1)->in(2) == in(2)) {
68 return in(1)->in(1);
69 }
70 if (in(1)->in(1) == in(2)) {
71 return in(1)->in(2);
72 }
73 }
74
75 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this;
76 }
77
78 //------------------------------Value------------------------------------------
79 // A subtract node differences it's two inputs.
80 const Type* SubNode::Value_common(PhaseValues* phase) const {
81 const Node* in1 = in(1);
82 const Node* in2 = in(2);
83 // Either input is TOP ==> the result is TOP
84 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
85 if( t1 == Type::TOP ) return Type::TOP;
86 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
87 if( t2 == Type::TOP ) return Type::TOP;
88
89 // Not correct for SubFnode and AddFNode (must check for infinity)
90 // Equal? Subtract is zero
91 if (in1->eqv_uncast(in2)) return add_id();
92
93 // Either input is BOTTOM ==> the result is the local BOTTOM
94 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM )
95 return bottom_type();
96
97 return nullptr;
98 }
99
100 const Type* SubNode::Value(PhaseGVN* phase) const {
101 const Type* t = Value_common(phase);
102 if (t != nullptr) {
103 return t;
104 }
105 const Type* t1 = phase->type(in(1));
106 const Type* t2 = phase->type(in(2));
107 return sub(t1,t2); // Local flavor of type subtraction
108
109 }
110
111 SubNode* SubNode::make(Node* in1, Node* in2, BasicType bt) {
112 switch (bt) {
113 case T_INT:
114 return new SubINode(in1, in2);
115 case T_LONG:
116 return new SubLNode(in1, in2);
117 default:
118 fatal("Not implemented for %s", type2name(bt));
119 }
120 return nullptr;
121 }
122
123 //=============================================================================
124 //------------------------------Helper function--------------------------------
125
126 static bool is_cloop_increment(Node* inc) {
127 precond(inc->Opcode() == Op_AddI || inc->Opcode() == Op_AddL);
128
129 if (!inc->in(1)->is_Phi()) {
130 return false;
131 }
132 const PhiNode* phi = inc->in(1)->as_Phi();
133
134 if (!phi->region()->is_CountedLoop()) {
135 return false;
136 }
137
138 return inc == phi->region()->as_CountedLoop()->incr();
139 }
140
141 // Given the expression '(x + C) - v', or
142 // 'v - (x + C)', we examine nodes '+' and 'v':
143 //
144 // 1. Do not convert if '+' is a counted-loop increment, because the '-' is
145 // loop invariant and converting extends the live-range of 'x' to overlap
146 // with the '+', forcing another register to be used in the loop.
147 //
148 // 2. Do not convert if 'v' is a counted-loop induction variable, because
149 // 'x' might be invariant.
150 //
151 static bool ok_to_convert(Node* inc, Node* var) {
152 return !(is_cloop_increment(inc) || var->is_cloop_ind_var());
153 }
154
155 static bool is_cloop_condition(BoolNode* bol) {
156 for (DUIterator_Fast imax, i = bol->fast_outs(imax); i < imax; i++) {
157 Node* out = bol->fast_out(i);
158 if (out->is_BaseCountedLoopEnd()) {
159 return true;
160 }
161 }
162 return false;
163 }
164
165 //------------------------------Ideal------------------------------------------
166 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){
167 Node *in1 = in(1);
168 Node *in2 = in(2);
169 uint op1 = in1->Opcode();
170 uint op2 = in2->Opcode();
171
172 #ifdef ASSERT
173 // Check for dead loop
174 if ((in1 == this) || (in2 == this) ||
175 ((op1 == Op_AddI || op1 == Op_SubI) &&
176 ((in1->in(1) == this) || (in1->in(2) == this) ||
177 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
178 assert(false, "dead loop in SubINode::Ideal");
179 }
180 #endif
181
182 const Type *t2 = phase->type( in2 );
183 if( t2 == Type::TOP ) return nullptr;
184 // Convert "x-c0" into "x+ -c0".
185 if( t2->base() == Type::Int ){ // Might be bottom or top...
186 const TypeInt *i = t2->is_int();
187 if( i->is_con() )
188 return new AddINode(in1, phase->intcon(java_negate(i->get_con())));
189 }
190
191 // Convert "(x+c0) - y" into (x-y) + c0"
192 // Do not collapse (x+c0)-y if "+" is a loop increment or
193 // if "y" is a loop induction variable.
194 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) {
195 const Type *tadd = phase->type( in1->in(2) );
196 if( tadd->singleton() && tadd != Type::TOP ) {
197 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 ));
198 return new AddINode( sub2, in1->in(2) );
199 }
200 }
201
202 // Convert "x - (y+c0)" into "(x-y) - c0" AND
203 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
204 // Need the same check as in above optimization but reversed.
205 if (op2 == Op_AddI
206 && ok_to_convert(in2, in1)
207 && in2->in(2)->Opcode() == Op_ConI) {
208 jint c0 = phase->type(in2->in(2))->isa_int()->get_con();
209 Node* in21 = in2->in(1);
210 if (in1->Opcode() == Op_ConI) {
211 // Match c1
212 jint c1 = phase->type(in1)->isa_int()->get_con();
213 Node* sub2 = phase->intcon(java_subtract(c1, c0));
214 return new SubINode(sub2, in21);
215 } else {
216 // Match x
217 Node* sub2 = phase->transform(new SubINode(in1, in21));
218 Node* neg_c0 = phase->intcon(java_negate(c0));
219 return new AddINode(sub2, neg_c0);
220 }
221 }
222
223 const Type *t1 = phase->type( in1 );
224 if( t1 == Type::TOP ) return nullptr;
225
226 #ifdef ASSERT
227 // Check for dead loop
228 if ((op2 == Op_AddI || op2 == Op_SubI) &&
229 ((in2->in(1) == this) || (in2->in(2) == this) ||
230 (in2->in(1) == in2) || (in2->in(2) == in2))) {
231 assert(false, "dead loop in SubINode::Ideal");
232 }
233 #endif
234
235 // Convert "x - (x+y)" into "-y"
236 if (op2 == Op_AddI && in1 == in2->in(1)) {
237 return new SubINode(phase->intcon(0), in2->in(2));
238 }
239 // Convert "(x-y) - x" into "-y"
240 if (op1 == Op_SubI && in1->in(1) == in2) {
241 return new SubINode(phase->intcon(0), in1->in(2));
242 }
243 // Convert "x - (y+x)" into "-y"
244 if (op2 == Op_AddI && in1 == in2->in(2)) {
245 return new SubINode(phase->intcon(0), in2->in(1));
246 }
247
248 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity().
249 if (t1 == TypeInt::ZERO && op2 == Op_SubI && phase->type(in2->in(1)) != TypeInt::ZERO) {
250 return new SubINode(in2->in(2), in2->in(1));
251 }
252
253 // Convert "0 - (x+con)" into "-con-x"
254 jint con;
255 if( t1 == TypeInt::ZERO && op2 == Op_AddI &&
256 (con = in2->in(2)->find_int_con(0)) != 0 )
257 return new SubINode( phase->intcon(-con), in2->in(1) );
258
259 // Convert "(X+A) - (X+B)" into "A - B"
260 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) )
261 return new SubINode( in1->in(2), in2->in(2) );
262
263 // Convert "(A+X) - (B+X)" into "A - B"
264 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) )
265 return new SubINode( in1->in(1), in2->in(1) );
266
267 // Convert "(A+X) - (X+B)" into "A - B"
268 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) )
269 return new SubINode( in1->in(1), in2->in(2) );
270
271 // Convert "(X+A) - (B+X)" into "A - B"
272 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) )
273 return new SubINode( in1->in(2), in2->in(1) );
274
275 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally
276 // nicer to optimize than subtract.
277 if( op2 == Op_SubI && in2->outcnt() == 1) {
278 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) );
279 return new SubINode( add1, in2->in(1) );
280 }
281
282 // Associative
283 if (op1 == Op_MulI && op2 == Op_MulI) {
284 Node* sub_in1 = nullptr;
285 Node* sub_in2 = nullptr;
286 Node* mul_in = nullptr;
287
288 if (in1->in(1) == in2->in(1)) {
289 // Convert "a*b-a*c into a*(b-c)
290 sub_in1 = in1->in(2);
291 sub_in2 = in2->in(2);
292 mul_in = in1->in(1);
293 } else if (in1->in(2) == in2->in(1)) {
294 // Convert a*b-b*c into b*(a-c)
295 sub_in1 = in1->in(1);
296 sub_in2 = in2->in(2);
297 mul_in = in1->in(2);
298 } else if (in1->in(2) == in2->in(2)) {
299 // Convert a*c-b*c into (a-b)*c
300 sub_in1 = in1->in(1);
301 sub_in2 = in2->in(1);
302 mul_in = in1->in(2);
303 } else if (in1->in(1) == in2->in(2)) {
304 // Convert a*b-c*a into a*(b-c)
305 sub_in1 = in1->in(2);
306 sub_in2 = in2->in(1);
307 mul_in = in1->in(1);
308 }
309
310 if (mul_in != nullptr) {
311 Node* sub = phase->transform(new SubINode(sub_in1, sub_in2));
312 return new MulINode(mul_in, sub);
313 }
314 }
315
316 // Convert "0-(A>>31)" into "(A>>>31)"
317 if ( op2 == Op_RShiftI ) {
318 Node *in21 = in2->in(1);
319 Node *in22 = in2->in(2);
320 const TypeInt *zero = phase->type(in1)->isa_int();
321 const TypeInt *t21 = phase->type(in21)->isa_int();
322 const TypeInt *t22 = phase->type(in22)->isa_int();
323 if ( t21 && t22 && zero == TypeInt::ZERO && t22->is_con(31) ) {
324 return new URShiftINode(in21, in22);
325 }
326 }
327
328 return nullptr;
329 }
330
331 //------------------------------sub--------------------------------------------
332 // A subtract node differences it's two inputs.
333 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const {
334 const TypeInt *r0 = t1->is_int(); // Handy access
335 const TypeInt *r1 = t2->is_int();
336 int32_t lo = java_subtract(r0->_lo, r1->_hi);
337 int32_t hi = java_subtract(r0->_hi, r1->_lo);
338
339 // We next check for 32-bit overflow.
340 // If that happens, we just assume all integers are possible.
341 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
342 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
343 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
344 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
345 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen));
346 else // Overflow; assume all integers
347 return TypeInt::INT;
348 }
349
350 //=============================================================================
351 //------------------------------Ideal------------------------------------------
352 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
353 Node *in1 = in(1);
354 Node *in2 = in(2);
355 uint op1 = in1->Opcode();
356 uint op2 = in2->Opcode();
357
358 #ifdef ASSERT
359 // Check for dead loop
360 if ((in1 == this) || (in2 == this) ||
361 ((op1 == Op_AddL || op1 == Op_SubL) &&
362 ((in1->in(1) == this) || (in1->in(2) == this) ||
363 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
364 assert(false, "dead loop in SubLNode::Ideal");
365 }
366 #endif
367
368 if( phase->type( in2 ) == Type::TOP ) return nullptr;
369 const TypeLong *i = phase->type( in2 )->isa_long();
370 // Convert "x-c0" into "x+ -c0".
371 if( i && // Might be bottom or top...
372 i->is_con() )
373 return new AddLNode(in1, phase->longcon(java_negate(i->get_con())));
374
375 // Convert "(x+c0) - y" into (x-y) + c0"
376 // Do not collapse (x+c0)-y if "+" is a loop increment or
377 // if "y" is a loop induction variable.
378 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) {
379 Node *in11 = in1->in(1);
380 const Type *tadd = phase->type( in1->in(2) );
381 if( tadd->singleton() && tadd != Type::TOP ) {
382 Node *sub2 = phase->transform( new SubLNode( in11, in2 ));
383 return new AddLNode( sub2, in1->in(2) );
384 }
385 }
386
387 // Convert "x - (y+c0)" into "(x-y) - c0" AND
388 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
389 // Need the same check as in above optimization but reversed.
390 if (op2 == Op_AddL
391 && ok_to_convert(in2, in1)
392 && in2->in(2)->Opcode() == Op_ConL) {
393 jlong c0 = phase->type(in2->in(2))->isa_long()->get_con();
394 Node* in21 = in2->in(1);
395 if (in1->Opcode() == Op_ConL) {
396 // Match c1
397 jlong c1 = phase->type(in1)->isa_long()->get_con();
398 Node* sub2 = phase->longcon(java_subtract(c1, c0));
399 return new SubLNode(sub2, in21);
400 } else {
401 Node* sub2 = phase->transform(new SubLNode(in1, in21));
402 Node* neg_c0 = phase->longcon(-c0);
403 return new AddLNode(sub2, neg_c0);
404 }
405 }
406
407 const Type *t1 = phase->type( in1 );
408 if( t1 == Type::TOP ) return nullptr;
409
410 #ifdef ASSERT
411 // Check for dead loop
412 if ((op2 == Op_AddL || op2 == Op_SubL) &&
413 ((in2->in(1) == this) || (in2->in(2) == this) ||
414 (in2->in(1) == in2) || (in2->in(2) == in2))) {
415 assert(false, "dead loop in SubLNode::Ideal");
416 }
417 #endif
418
419 // Convert "x - (x+y)" into "-y"
420 if (op2 == Op_AddL && in1 == in2->in(1)) {
421 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(2));
422 }
423 // Convert "(x-y) - x" into "-y"
424 if (op1 == Op_SubL && in1->in(1) == in2) {
425 return new SubLNode(phase->makecon(TypeLong::ZERO), in1->in(2));
426 }
427 // Convert "x - (y+x)" into "-y"
428 if (op2 == Op_AddL && in1 == in2->in(2)) {
429 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(1));
430 }
431
432 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity.
433 if (t1 == TypeLong::ZERO && op2 == Op_SubL && phase->type(in2->in(1)) != TypeLong::ZERO) {
434 return new SubLNode(in2->in(2), in2->in(1));
435 }
436
437 // Convert "(X+A) - (X+B)" into "A - B"
438 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) )
439 return new SubLNode( in1->in(2), in2->in(2) );
440
441 // Convert "(A+X) - (B+X)" into "A - B"
442 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) )
443 return new SubLNode( in1->in(1), in2->in(1) );
444
445 // Convert "(A+X) - (X+B)" into "A - B"
446 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(1) )
447 return new SubLNode( in1->in(1), in2->in(2) );
448
449 // Convert "(X+A) - (B+X)" into "A - B"
450 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(2) )
451 return new SubLNode( in1->in(2), in2->in(1) );
452
453 // Convert "A-(B-C)" into (A+C)-B"
454 if( op2 == Op_SubL && in2->outcnt() == 1) {
455 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) );
456 return new SubLNode( add1, in2->in(1) );
457 }
458
459 // Associative
460 if (op1 == Op_MulL && op2 == Op_MulL) {
461 Node* sub_in1 = nullptr;
462 Node* sub_in2 = nullptr;
463 Node* mul_in = nullptr;
464
465 if (in1->in(1) == in2->in(1)) {
466 // Convert "a*b-a*c into a*(b+c)
467 sub_in1 = in1->in(2);
468 sub_in2 = in2->in(2);
469 mul_in = in1->in(1);
470 } else if (in1->in(2) == in2->in(1)) {
471 // Convert a*b-b*c into b*(a-c)
472 sub_in1 = in1->in(1);
473 sub_in2 = in2->in(2);
474 mul_in = in1->in(2);
475 } else if (in1->in(2) == in2->in(2)) {
476 // Convert a*c-b*c into (a-b)*c
477 sub_in1 = in1->in(1);
478 sub_in2 = in2->in(1);
479 mul_in = in1->in(2);
480 } else if (in1->in(1) == in2->in(2)) {
481 // Convert a*b-c*a into a*(b-c)
482 sub_in1 = in1->in(2);
483 sub_in2 = in2->in(1);
484 mul_in = in1->in(1);
485 }
486
487 if (mul_in != nullptr) {
488 Node* sub = phase->transform(new SubLNode(sub_in1, sub_in2));
489 return new MulLNode(mul_in, sub);
490 }
491 }
492
493 // Convert "0L-(A>>63)" into "(A>>>63)"
494 if ( op2 == Op_RShiftL ) {
495 Node *in21 = in2->in(1);
496 Node *in22 = in2->in(2);
497 const TypeLong *zero = phase->type(in1)->isa_long();
498 const TypeLong *t21 = phase->type(in21)->isa_long();
499 const TypeInt *t22 = phase->type(in22)->isa_int();
500 if ( t21 && t22 && zero == TypeLong::ZERO && t22->is_con(63) ) {
501 return new URShiftLNode(in21, in22);
502 }
503 }
504
505 return nullptr;
506 }
507
508 //------------------------------sub--------------------------------------------
509 // A subtract node differences it's two inputs.
510 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const {
511 const TypeLong *r0 = t1->is_long(); // Handy access
512 const TypeLong *r1 = t2->is_long();
513 jlong lo = java_subtract(r0->_lo, r1->_hi);
514 jlong hi = java_subtract(r0->_hi, r1->_lo);
515
516 // We next check for 32-bit overflow.
517 // If that happens, we just assume all integers are possible.
518 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
519 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
520 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
521 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
522 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen));
523 else // Overflow; assume all integers
524 return TypeLong::LONG;
525 }
526
527 //=============================================================================
528 //------------------------------Value------------------------------------------
529 // A subtract node differences its two inputs.
530 const Type* SubFPNode::Value(PhaseGVN* phase) const {
531 const Node* in1 = in(1);
532 const Node* in2 = in(2);
533 // Either input is TOP ==> the result is TOP
534 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
535 if( t1 == Type::TOP ) return Type::TOP;
536 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
537 if( t2 == Type::TOP ) return Type::TOP;
538
539 // if both operands are infinity of same sign, the result is NaN; do
540 // not replace with zero
541 if (t1->is_finite() && t2->is_finite() && in1 == in2) {
542 return add_id();
543 }
544
545 // Either input is BOTTOM ==> the result is the local BOTTOM
546 const Type *bot = bottom_type();
547 if( (t1 == bot) || (t2 == bot) ||
548 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
549 return bot;
550
551 return sub(t1,t2); // Local flavor of type subtraction
552 }
553
554
555 //=============================================================================
556 //------------------------------Ideal------------------------------------------
557 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
558 const Type *t2 = phase->type( in(2) );
559 // Convert "x-c0" into "x+ -c0".
560 if( t2->base() == Type::FloatCon ) { // Might be bottom or top...
561 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) );
562 }
563
564 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes
565 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0.
566 //if( phase->type(in(1)) == TypeF::ZERO )
567 //return new (phase->C, 2) NegFNode(in(2));
568
569 return nullptr;
570 }
571
572 //------------------------------sub--------------------------------------------
573 // A subtract node differences its two inputs.
574 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const {
575 // no folding if one of operands is infinity or NaN, do not do constant folding
576 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) {
577 return TypeF::make( t1->getf() - t2->getf() );
578 }
579 else if( g_isnan(t1->getf()) ) {
580 return t1;
581 }
582 else if( g_isnan(t2->getf()) ) {
583 return t2;
584 }
585 else {
586 return Type::FLOAT;
587 }
588 }
589
590 //=============================================================================
591 //------------------------------Ideal------------------------------------------
592 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){
593 const Type *t2 = phase->type( in(2) );
594 // Convert "x-c0" into "x+ -c0".
595 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top...
596 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) );
597 }
598
599 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes
600 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0.
601 //if( phase->type(in(1)) == TypeD::ZERO )
602 //return new (phase->C, 2) NegDNode(in(2));
603
604 return nullptr;
605 }
606
607 //------------------------------sub--------------------------------------------
608 // A subtract node differences its two inputs.
609 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const {
610 // no folding if one of operands is infinity or NaN, do not do constant folding
611 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) {
612 return TypeD::make( t1->getd() - t2->getd() );
613 }
614 else if( g_isnan(t1->getd()) ) {
615 return t1;
616 }
617 else if( g_isnan(t2->getd()) ) {
618 return t2;
619 }
620 else {
621 return Type::DOUBLE;
622 }
623 }
624
625 //=============================================================================
626 //------------------------------Idealize---------------------------------------
627 // Unlike SubNodes, compare must still flatten return value to the
628 // range -1, 0, 1.
629 // And optimizations like those for (X + Y) - X fail if overflow happens.
630 Node* CmpNode::Identity(PhaseGVN* phase) {
631 return this;
632 }
633
634 CmpNode *CmpNode::make(Node *in1, Node *in2, BasicType bt, bool unsigned_comp) {
635 switch (bt) {
636 case T_INT:
637 if (unsigned_comp) {
638 return new CmpUNode(in1, in2);
639 }
640 return new CmpINode(in1, in2);
641 case T_LONG:
642 if (unsigned_comp) {
643 return new CmpULNode(in1, in2);
644 }
645 return new CmpLNode(in1, in2);
646 case T_OBJECT:
647 case T_ARRAY:
648 case T_ADDRESS:
649 case T_METADATA:
650 return new CmpPNode(in1, in2);
651 case T_NARROWOOP:
652 case T_NARROWKLASS:
653 return new CmpNNode(in1, in2);
654 default:
655 fatal("Not implemented for %s", type2name(bt));
656 }
657 return nullptr;
658 }
659
660 //=============================================================================
661 //------------------------------cmp--------------------------------------------
662 // Simplify a CmpI (compare 2 integers) node, based on local information.
663 // If both inputs are constants, compare them.
664 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const {
665 const TypeInt *r0 = t1->is_int(); // Handy access
666 const TypeInt *r1 = t2->is_int();
667
668 if( r0->_hi < r1->_lo ) // Range is always low?
669 return TypeInt::CC_LT;
670 else if( r0->_lo > r1->_hi ) // Range is always high?
671 return TypeInt::CC_GT;
672
673 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
674 assert(r0->get_con() == r1->get_con(), "must be equal");
675 return TypeInt::CC_EQ; // Equal results.
676 } else if( r0->_hi == r1->_lo ) // Range is never high?
677 return TypeInt::CC_LE;
678 else if( r0->_lo == r1->_hi ) // Range is never low?
679 return TypeInt::CC_GE;
680 return TypeInt::CC; // else use worst case results
681 }
682
683 const Type* CmpINode::Value(PhaseGVN* phase) const {
684 Node* in1 = in(1);
685 Node* in2 = in(2);
686 // If this test is the zero trip guard for a main or post loop, check whether, with the opaque node removed, the test
687 // would constant fold so the loop is never entered. If so return the type of the test without the opaque node removed:
688 // make the loop unreachable.
689 // The reason for this is that the iv phi captures the bounds of the loop and if the loop becomes unreachable, it can
690 // become top. In that case, the loop must be removed.
691 // This is safe because:
692 // - as optimizations proceed, the range of iterations executed by the main loop narrows. If no iterations remain, then
693 // we're done with optimizations for that loop.
694 // - the post loop is initially not reachable but as long as there's a main loop, the zero trip guard for the post
695 // 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
696 // loop is removed, there's no need to preserve the zero trip guard for the post loop anymore.
697 if (in1 != nullptr && in2 != nullptr) {
698 uint input = 0;
699 Node* cmp = nullptr;
700 BoolTest::mask test;
701 if (in1->Opcode() == Op_OpaqueZeroTripGuard && phase->type(in1) != Type::TOP) {
702 cmp = new CmpINode(in1->in(1), in2);
703 test = ((OpaqueZeroTripGuardNode*)in1)->_loop_entered_mask;
704 }
705 if (in2->Opcode() == Op_OpaqueZeroTripGuard && phase->type(in2) != Type::TOP) {
706 assert(cmp == nullptr, "A cmp with 2 OpaqueZeroTripGuard inputs");
707 cmp = new CmpINode(in1, in2->in(1));
708 test = ((OpaqueZeroTripGuardNode*)in2)->_loop_entered_mask;
709 }
710 if (cmp != nullptr) {
711 const Type* cmp_t = cmp->Value(phase);
712 const Type* t = BoolTest(test).cc2logical(cmp_t);
713 cmp->destruct(phase);
714 if (t == TypeInt::ZERO) {
715 return cmp_t;
716 }
717 }
718 }
719
720 return SubNode::Value(phase);
721 }
722
723
724 // Simplify a CmpU (compare 2 integers) node, based on local information.
725 // If both inputs are constants, compare them.
726 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const {
727 assert(!t1->isa_ptr(), "obsolete usage of CmpU");
728
729 // comparing two unsigned ints
730 const TypeInt *r0 = t1->is_int(); // Handy access
731 const TypeInt *r1 = t2->is_int();
732
733 // Current installed version
734 // Compare ranges for non-overlap
735 juint lo0 = r0->_lo;
736 juint hi0 = r0->_hi;
737 juint lo1 = r1->_lo;
738 juint hi1 = r1->_hi;
739
740 // If either one has both negative and positive values,
741 // it therefore contains both 0 and -1, and since [0..-1] is the
742 // full unsigned range, the type must act as an unsigned bottom.
743 bool bot0 = ((jint)(lo0 ^ hi0) < 0);
744 bool bot1 = ((jint)(lo1 ^ hi1) < 0);
745
746 if (bot0 || bot1) {
747 // All unsigned values are LE -1 and GE 0.
748 if (lo0 == 0 && hi0 == 0) {
749 return TypeInt::CC_LE; // 0 <= bot
750 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) {
751 return TypeInt::CC_GE; // -1 >= bot
752 } else if (lo1 == 0 && hi1 == 0) {
753 return TypeInt::CC_GE; // bot >= 0
754 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) {
755 return TypeInt::CC_LE; // bot <= -1
756 }
757 } else {
758 // We can use ranges of the form [lo..hi] if signs are the same.
759 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
760 // results are reversed, '-' > '+' for unsigned compare
761 if (hi0 < lo1) {
762 return TypeInt::CC_LT; // smaller
763 } else if (lo0 > hi1) {
764 return TypeInt::CC_GT; // greater
765 } else if (hi0 == lo1 && lo0 == hi1) {
766 return TypeInt::CC_EQ; // Equal results
767 } else if (lo0 >= hi1) {
768 return TypeInt::CC_GE;
769 } else if (hi0 <= lo1) {
770 // Check for special case in Hashtable::get. (See below.)
771 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
772 return TypeInt::CC_LT;
773 return TypeInt::CC_LE;
774 }
775 }
776 // Check for special case in Hashtable::get - the hash index is
777 // mod'ed to the table size so the following range check is useless.
778 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have
779 // to be positive.
780 // (This is a gross hack, since the sub method never
781 // looks at the structure of the node in any other case.)
782 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
783 return TypeInt::CC_LT;
784 return TypeInt::CC; // else use worst case results
785 }
786
787 const Type* CmpUNode::Value(PhaseGVN* phase) const {
788 const Type* t = SubNode::Value_common(phase);
789 if (t != nullptr) {
790 return t;
791 }
792 const Node* in1 = in(1);
793 const Node* in2 = in(2);
794 const Type* t1 = phase->type(in1);
795 const Type* t2 = phase->type(in2);
796 assert(t1->isa_int(), "CmpU has only Int type inputs");
797 if (t2 == TypeInt::INT) { // Compare to bottom?
798 return bottom_type();
799 }
800
801 const Type* t_sub = sub(t1, t2); // compare based on immediate inputs
802
803 uint in1_op = in1->Opcode();
804 if (in1_op == Op_AddI || in1_op == Op_SubI) {
805 // The problem rise when result of AddI(SubI) may overflow
806 // signed integer value. Let say the input type is
807 // [256, maxint] then +128 will create 2 ranges due to
808 // overflow: [minint, minint+127] and [384, maxint].
809 // But C2 type system keep only 1 type range and as result
810 // it use general [minint, maxint] for this case which we
811 // can't optimize.
812 //
813 // Make 2 separate type ranges based on types of AddI(SubI) inputs
814 // and compare results of their compare. If results are the same
815 // CmpU node can be optimized.
816 const Node* in11 = in1->in(1);
817 const Node* in12 = in1->in(2);
818 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11);
819 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12);
820 // Skip cases when input types are top or bottom.
821 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) &&
822 (t12 != Type::TOP) && (t12 != TypeInt::INT)) {
823 const TypeInt *r0 = t11->is_int();
824 const TypeInt *r1 = t12->is_int();
825 jlong lo_r0 = r0->_lo;
826 jlong hi_r0 = r0->_hi;
827 jlong lo_r1 = r1->_lo;
828 jlong hi_r1 = r1->_hi;
829 if (in1_op == Op_SubI) {
830 jlong tmp = hi_r1;
831 hi_r1 = -lo_r1;
832 lo_r1 = -tmp;
833 // Note, for substructing [minint,x] type range
834 // long arithmetic provides correct overflow answer.
835 // The confusion come from the fact that in 32-bit
836 // -minint == minint but in 64-bit -minint == maxint+1.
837 }
838 jlong lo_long = lo_r0 + lo_r1;
839 jlong hi_long = hi_r0 + hi_r1;
840 int lo_tr1 = min_jint;
841 int hi_tr1 = (int)hi_long;
842 int lo_tr2 = (int)lo_long;
843 int hi_tr2 = max_jint;
844 bool underflow = lo_long != (jlong)lo_tr2;
845 bool overflow = hi_long != (jlong)hi_tr1;
846 // Use sub(t1, t2) when there is no overflow (one type range)
847 // or when both overflow and underflow (too complex).
848 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) {
849 // Overflow only on one boundary, compare 2 separate type ranges.
850 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
851 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w);
852 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w);
853 const TypeInt* cmp1 = sub(tr1, t2)->is_int();
854 const TypeInt* cmp2 = sub(tr2, t2)->is_int();
855 // Compute union, so that cmp handles all possible results from the two cases
856 const Type* t_cmp = cmp1->meet(cmp2);
857 // Pick narrowest type, based on overflow computation and on immediate inputs
858 return t_sub->filter(t_cmp);
859 }
860 }
861 }
862
863 return t_sub;
864 }
865
866 bool CmpUNode::is_index_range_check() const {
867 // Check for the "(X ModI Y) CmpU Y" shape
868 return (in(1)->Opcode() == Op_ModI &&
869 in(1)->in(2)->eqv_uncast(in(2)));
870 }
871
872 //------------------------------Idealize---------------------------------------
873 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
874 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) {
875 switch (in(1)->Opcode()) {
876 case Op_CmpU3: // Collapse a CmpU3/CmpI into a CmpU
877 return new CmpUNode(in(1)->in(1),in(1)->in(2));
878 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL
879 return new CmpLNode(in(1)->in(1),in(1)->in(2));
880 case Op_CmpUL3: // Collapse a CmpUL3/CmpI into a CmpUL
881 return new CmpULNode(in(1)->in(1),in(1)->in(2));
882 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF
883 return new CmpFNode(in(1)->in(1),in(1)->in(2));
884 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD
885 return new CmpDNode(in(1)->in(1),in(1)->in(2));
886 //case Op_SubI:
887 // If (x - y) cannot overflow, then ((x - y) <?> 0)
888 // can be turned into (x <?> y).
889 // This is handled (with more general cases) by Ideal_sub_algebra.
890 }
891 }
892 return nullptr; // No change
893 }
894
895 Node *CmpLNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
896 const TypeLong *t2 = phase->type(in(2))->isa_long();
897 if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) {
898 const jlong con = t2->get_con();
899 if (con >= min_jint && con <= max_jint) {
900 return new CmpINode(in(1)->in(1), phase->intcon((jint)con));
901 }
902 }
903 return nullptr;
904 }
905
906 //=============================================================================
907 // Simplify a CmpL (compare 2 longs ) node, based on local information.
908 // If both inputs are constants, compare them.
909 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const {
910 const TypeLong *r0 = t1->is_long(); // Handy access
911 const TypeLong *r1 = t2->is_long();
912
913 if( r0->_hi < r1->_lo ) // Range is always low?
914 return TypeInt::CC_LT;
915 else if( r0->_lo > r1->_hi ) // Range is always high?
916 return TypeInt::CC_GT;
917
918 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
919 assert(r0->get_con() == r1->get_con(), "must be equal");
920 return TypeInt::CC_EQ; // Equal results.
921 } else if( r0->_hi == r1->_lo ) // Range is never high?
922 return TypeInt::CC_LE;
923 else if( r0->_lo == r1->_hi ) // Range is never low?
924 return TypeInt::CC_GE;
925 return TypeInt::CC; // else use worst case results
926 }
927
928
929 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information.
930 // If both inputs are constants, compare them.
931 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const {
932 assert(!t1->isa_ptr(), "obsolete usage of CmpUL");
933
934 // comparing two unsigned longs
935 const TypeLong* r0 = t1->is_long(); // Handy access
936 const TypeLong* r1 = t2->is_long();
937
938 // Current installed version
939 // Compare ranges for non-overlap
940 julong lo0 = r0->_lo;
941 julong hi0 = r0->_hi;
942 julong lo1 = r1->_lo;
943 julong hi1 = r1->_hi;
944
945 // If either one has both negative and positive values,
946 // it therefore contains both 0 and -1, and since [0..-1] is the
947 // full unsigned range, the type must act as an unsigned bottom.
948 bool bot0 = ((jlong)(lo0 ^ hi0) < 0);
949 bool bot1 = ((jlong)(lo1 ^ hi1) < 0);
950
951 if (bot0 || bot1) {
952 // All unsigned values are LE -1 and GE 0.
953 if (lo0 == 0 && hi0 == 0) {
954 return TypeInt::CC_LE; // 0 <= bot
955 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) {
956 return TypeInt::CC_GE; // -1 >= bot
957 } else if (lo1 == 0 && hi1 == 0) {
958 return TypeInt::CC_GE; // bot >= 0
959 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) {
960 return TypeInt::CC_LE; // bot <= -1
961 }
962 } else {
963 // We can use ranges of the form [lo..hi] if signs are the same.
964 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
965 // results are reversed, '-' > '+' for unsigned compare
966 if (hi0 < lo1) {
967 return TypeInt::CC_LT; // smaller
968 } else if (lo0 > hi1) {
969 return TypeInt::CC_GT; // greater
970 } else if (hi0 == lo1 && lo0 == hi1) {
971 return TypeInt::CC_EQ; // Equal results
972 } else if (lo0 >= hi1) {
973 return TypeInt::CC_GE;
974 } else if (hi0 <= lo1) {
975 return TypeInt::CC_LE;
976 }
977 }
978
979 return TypeInt::CC; // else use worst case results
980 }
981
982 //=============================================================================
983 //------------------------------sub--------------------------------------------
984 // Simplify an CmpP (compare 2 pointers) node, based on local information.
985 // If both inputs are constants, compare them.
986 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const {
987 const TypePtr *r0 = t1->is_ptr(); // Handy access
988 const TypePtr *r1 = t2->is_ptr();
989
990 // Undefined inputs makes for an undefined result
991 if( TypePtr::above_centerline(r0->_ptr) ||
992 TypePtr::above_centerline(r1->_ptr) )
993 return Type::TOP;
994
995 if (r0 == r1 && r0->singleton()) {
996 // Equal pointer constants (klasses, nulls, etc.)
997 return TypeInt::CC_EQ;
998 }
999
1000 // See if it is 2 unrelated classes.
1001 const TypeOopPtr* p0 = r0->isa_oopptr();
1002 const TypeOopPtr* p1 = r1->isa_oopptr();
1003 const TypeKlassPtr* k0 = r0->isa_klassptr();
1004 const TypeKlassPtr* k1 = r1->isa_klassptr();
1005 if ((p0 && p1) || (k0 && k1)) {
1006 if (p0 && p1) {
1007 Node* in1 = in(1)->uncast();
1008 Node* in2 = in(2)->uncast();
1009 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1);
1010 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2);
1011 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, nullptr)) {
1012 return TypeInt::CC_GT; // different pointers
1013 }
1014 }
1015 bool xklass0 = p0 ? p0->klass_is_exact() : k0->klass_is_exact();
1016 bool xklass1 = p1 ? p1->klass_is_exact() : k1->klass_is_exact();
1017 bool unrelated_classes = false;
1018
1019 if ((p0 && p0->is_same_java_type_as(p1)) ||
1020 (k0 && k0->is_same_java_type_as(k1))) {
1021 } else if ((p0 && !p1->maybe_java_subtype_of(p0) && !p0->maybe_java_subtype_of(p1)) ||
1022 (k0 && !k1->maybe_java_subtype_of(k0) && !k0->maybe_java_subtype_of(k1))) {
1023 unrelated_classes = true;
1024 } else if ((p0 && !p1->maybe_java_subtype_of(p0)) ||
1025 (k0 && !k1->maybe_java_subtype_of(k0))) {
1026 unrelated_classes = xklass1;
1027 } else if ((p0 && !p0->maybe_java_subtype_of(p1)) ||
1028 (k0 && !k0->maybe_java_subtype_of(k1))) {
1029 unrelated_classes = xklass0;
1030 }
1031
1032 if (unrelated_classes) {
1033 // The oops classes are known to be unrelated. If the joined PTRs of
1034 // two oops is not Null and not Bottom, then we are sure that one
1035 // of the two oops is non-null, and the comparison will always fail.
1036 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
1037 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
1038 return TypeInt::CC_GT;
1039 }
1040 }
1041 }
1042
1043 // Known constants can be compared exactly
1044 // Null can be distinguished from any NotNull pointers
1045 // Unknown inputs makes an unknown result
1046 if( r0->singleton() ) {
1047 intptr_t bits0 = r0->get_con();
1048 if( r1->singleton() )
1049 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
1050 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1051 } else if( r1->singleton() ) {
1052 intptr_t bits1 = r1->get_con();
1053 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1054 } else
1055 return TypeInt::CC;
1056 }
1057
1058 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) {
1059 // Return the klass node for (indirect load from OopHandle)
1060 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
1061 // or null if not matching.
1062 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1063 n = bs->step_over_gc_barrier(n);
1064
1065 if (n->Opcode() != Op_LoadP) return nullptr;
1066
1067 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1068 if (!tp || tp->instance_klass() != phase->C->env()->Class_klass()) return nullptr;
1069
1070 Node* adr = n->in(MemNode::Address);
1071 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier.
1072 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return nullptr;
1073 adr = adr->in(MemNode::Address);
1074
1075 intptr_t off = 0;
1076 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off);
1077 if (k == nullptr) return nullptr;
1078 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr();
1079 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return nullptr;
1080
1081 // We've found the klass node of a Java mirror load.
1082 return k;
1083 }
1084
1085 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) {
1086 // for ConP(Foo.class) return ConP(Foo.klass)
1087 // otherwise return null
1088 if (!n->is_Con()) return nullptr;
1089
1090 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1091 if (!tp) return nullptr;
1092
1093 ciType* mirror_type = tp->java_mirror_type();
1094 // TypeInstPtr::java_mirror_type() returns non-null for compile-
1095 // time Class constants only.
1096 if (!mirror_type) return nullptr;
1097
1098 // x.getClass() == int.class can never be true (for all primitive types)
1099 // Return a ConP(null) node for this case.
1100 if (mirror_type->is_classless()) {
1101 return phase->makecon(TypePtr::NULL_PTR);
1102 }
1103
1104 // return the ConP(Foo.klass)
1105 assert(mirror_type->is_klass(), "mirror_type should represent a Klass*");
1106 return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass(), Type::trust_interfaces));
1107 }
1108
1109 //------------------------------Ideal------------------------------------------
1110 // Normalize comparisons between Java mirror loads to compare the klass instead.
1111 //
1112 // Also check for the case of comparing an unknown klass loaded from the primary
1113 // super-type array vs a known klass with no subtypes. This amounts to
1114 // checking to see an unknown klass subtypes a known klass with no subtypes;
1115 // this only happens on an exact match. We can shorten this test by 1 load.
1116 Node *CmpPNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1117 // Normalize comparisons between Java mirrors into comparisons of the low-
1118 // level klass, where a dependent load could be shortened.
1119 //
1120 // The new pattern has a nice effect of matching the same pattern used in the
1121 // fast path of instanceof/checkcast/Class.isInstance(), which allows
1122 // redundant exact type check be optimized away by GVN.
1123 // For example, in
1124 // if (x.getClass() == Foo.class) {
1125 // Foo foo = (Foo) x;
1126 // // ... use a ...
1127 // }
1128 // a CmpPNode could be shared between if_acmpne and checkcast
1129 {
1130 Node* k1 = isa_java_mirror_load(phase, in(1));
1131 Node* k2 = isa_java_mirror_load(phase, in(2));
1132 Node* conk2 = isa_const_java_mirror(phase, in(2));
1133
1134 if (k1 && (k2 || conk2)) {
1135 Node* lhs = k1;
1136 Node* rhs = (k2 != nullptr) ? k2 : conk2;
1137 set_req_X(1, lhs, phase);
1138 set_req_X(2, rhs, phase);
1139 return this;
1140 }
1141 }
1142
1143 // Constant pointer on right?
1144 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
1145 if (t2 == nullptr || !t2->klass_is_exact())
1146 return nullptr;
1147 // Get the constant klass we are comparing to.
1148 ciKlass* superklass = t2->exact_klass();
1149
1150 // Now check for LoadKlass on left.
1151 Node* ldk1 = in(1);
1152 if (ldk1->is_DecodeNKlass()) {
1153 ldk1 = ldk1->in(1);
1154 if (ldk1->Opcode() != Op_LoadNKlass )
1155 return nullptr;
1156 } else if (ldk1->Opcode() != Op_LoadKlass )
1157 return nullptr;
1158 // Take apart the address of the LoadKlass:
1159 Node* adr1 = ldk1->in(MemNode::Address);
1160 intptr_t con2 = 0;
1161 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
1162 if (ldk2 == nullptr)
1163 return nullptr;
1164 if (con2 == oopDesc::klass_offset_in_bytes()) {
1165 // We are inspecting an object's concrete class.
1166 // Short-circuit the check if the query is abstract.
1167 if (superklass->is_interface() ||
1168 superklass->is_abstract()) {
1169 // Make it come out always false:
1170 this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
1171 return this;
1172 }
1173 }
1174
1175 // Check for a LoadKlass from primary supertype array.
1176 // Any nested loadklass from loadklass+con must be from the p.s. array.
1177 if (ldk2->is_DecodeNKlass()) {
1178 // Keep ldk2 as DecodeN since it could be used in CmpP below.
1179 if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
1180 return nullptr;
1181 } else if (ldk2->Opcode() != Op_LoadKlass)
1182 return nullptr;
1183
1184 // Verify that we understand the situation
1185 if (con2 != (intptr_t) superklass->super_check_offset())
1186 return nullptr; // Might be element-klass loading from array klass
1187
1188 // If 'superklass' has no subklasses and is not an interface, then we are
1189 // assured that the only input which will pass the type check is
1190 // 'superklass' itself.
1191 //
1192 // We could be more liberal here, and allow the optimization on interfaces
1193 // which have a single implementor. This would require us to increase the
1194 // expressiveness of the add_dependency() mechanism.
1195 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now.
1196
1197 // Object arrays must have their base element have no subtypes
1198 while (superklass->is_obj_array_klass()) {
1199 ciType* elem = superklass->as_obj_array_klass()->element_type();
1200 superklass = elem->as_klass();
1201 }
1202 if (superklass->is_instance_klass()) {
1203 ciInstanceKlass* ik = superklass->as_instance_klass();
1204 if (ik->has_subklass() || ik->is_interface()) return nullptr;
1205 // Add a dependency if there is a chance that a subclass will be added later.
1206 if (!ik->is_final()) {
1207 phase->C->dependencies()->assert_leaf_type(ik);
1208 }
1209 }
1210
1211 // Bypass the dependent load, and compare directly
1212 this->set_req_X(1, ldk2, phase);
1213
1214 return this;
1215 }
1216
1217 //=============================================================================
1218 //------------------------------sub--------------------------------------------
1219 // Simplify an CmpN (compare 2 pointers) node, based on local information.
1220 // If both inputs are constants, compare them.
1221 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
1222 ShouldNotReachHere();
1223 return bottom_type();
1224 }
1225
1226 //------------------------------Ideal------------------------------------------
1227 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1228 return nullptr;
1229 }
1230
1231 //=============================================================================
1232 //------------------------------Value------------------------------------------
1233 // Simplify an CmpF (compare 2 floats ) node, based on local information.
1234 // If both inputs are constants, compare them.
1235 const Type* CmpFNode::Value(PhaseGVN* phase) const {
1236 const Node* in1 = in(1);
1237 const Node* in2 = in(2);
1238 // Either input is TOP ==> the result is TOP
1239 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1240 if( t1 == Type::TOP ) return Type::TOP;
1241 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1242 if( t2 == Type::TOP ) return Type::TOP;
1243
1244 // Not constants? Don't know squat - even if they are the same
1245 // value! If they are NaN's they compare to LT instead of EQ.
1246 const TypeF *tf1 = t1->isa_float_constant();
1247 const TypeF *tf2 = t2->isa_float_constant();
1248 if( !tf1 || !tf2 ) return TypeInt::CC;
1249
1250 // This implements the Java bytecode fcmpl, so unordered returns -1.
1251 if( tf1->is_nan() || tf2->is_nan() )
1252 return TypeInt::CC_LT;
1253
1254 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
1255 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
1256 assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
1257 return TypeInt::CC_EQ;
1258 }
1259
1260
1261 //=============================================================================
1262 //------------------------------Value------------------------------------------
1263 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
1264 // If both inputs are constants, compare them.
1265 const Type* CmpDNode::Value(PhaseGVN* phase) const {
1266 const Node* in1 = in(1);
1267 const Node* in2 = in(2);
1268 // Either input is TOP ==> the result is TOP
1269 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1270 if( t1 == Type::TOP ) return Type::TOP;
1271 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1272 if( t2 == Type::TOP ) return Type::TOP;
1273
1274 // Not constants? Don't know squat - even if they are the same
1275 // value! If they are NaN's they compare to LT instead of EQ.
1276 const TypeD *td1 = t1->isa_double_constant();
1277 const TypeD *td2 = t2->isa_double_constant();
1278 if( !td1 || !td2 ) return TypeInt::CC;
1279
1280 // This implements the Java bytecode dcmpl, so unordered returns -1.
1281 if( td1->is_nan() || td2->is_nan() )
1282 return TypeInt::CC_LT;
1283
1284 if( td1->_d < td2->_d ) return TypeInt::CC_LT;
1285 if( td1->_d > td2->_d ) return TypeInt::CC_GT;
1286 assert( td1->_d == td2->_d, "do not understand FP behavior" );
1287 return TypeInt::CC_EQ;
1288 }
1289
1290 //------------------------------Ideal------------------------------------------
1291 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
1292 // Check if we can change this to a CmpF and remove a ConvD2F operation.
1293 // Change (CMPD (F2D (float)) (ConD value))
1294 // To (CMPF (float) (ConF value))
1295 // Valid when 'value' does not lose precision as a float.
1296 // Benefits: eliminates conversion, does not require 24-bit mode
1297
1298 // NaNs prevent commuting operands. This transform works regardless of the
1299 // order of ConD and ConvF2D inputs by preserving the original order.
1300 int idx_f2d = 1; // ConvF2D on left side?
1301 if( in(idx_f2d)->Opcode() != Op_ConvF2D )
1302 idx_f2d = 2; // No, swap to check for reversed args
1303 int idx_con = 3-idx_f2d; // Check for the constant on other input
1304
1305 if( ConvertCmpD2CmpF &&
1306 in(idx_f2d)->Opcode() == Op_ConvF2D &&
1307 in(idx_con)->Opcode() == Op_ConD ) {
1308 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
1309 double t2_value_as_double = t2->_d;
1310 float t2_value_as_float = (float)t2_value_as_double;
1311 if( t2_value_as_double == (double)t2_value_as_float ) {
1312 // Test value can be represented as a float
1313 // Eliminate the conversion to double and create new comparison
1314 Node *new_in1 = in(idx_f2d)->in(1);
1315 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
1316 if( idx_f2d != 1 ) { // Must flip args to match original order
1317 Node *tmp = new_in1;
1318 new_in1 = new_in2;
1319 new_in2 = tmp;
1320 }
1321 CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
1322 ? new CmpF3Node( new_in1, new_in2 )
1323 : new CmpFNode ( new_in1, new_in2 ) ;
1324 return new_cmp; // Changed to CmpFNode
1325 }
1326 // Testing value required the precision of a double
1327 }
1328 return nullptr; // No change
1329 }
1330
1331
1332 //=============================================================================
1333 //------------------------------cc2logical-------------------------------------
1334 // Convert a condition code type to a logical type
1335 const Type *BoolTest::cc2logical( const Type *CC ) const {
1336 if( CC == Type::TOP ) return Type::TOP;
1337 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
1338 const TypeInt *ti = CC->is_int();
1339 if( ti->is_con() ) { // Only 1 kind of condition codes set?
1340 // Match low order 2 bits
1341 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
1342 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result
1343 return TypeInt::make(tmp); // Boolean result
1344 }
1345
1346 if( CC == TypeInt::CC_GE ) {
1347 if( _test == ge ) return TypeInt::ONE;
1348 if( _test == lt ) return TypeInt::ZERO;
1349 }
1350 if( CC == TypeInt::CC_LE ) {
1351 if( _test == le ) return TypeInt::ONE;
1352 if( _test == gt ) return TypeInt::ZERO;
1353 }
1354
1355 return TypeInt::BOOL;
1356 }
1357
1358 //------------------------------dump_spec-------------------------------------
1359 // Print special per-node info
1360 void BoolTest::dump_on(outputStream *st) const {
1361 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"};
1362 st->print("%s", msg[_test]);
1363 }
1364
1365 // Returns the logical AND of two tests (or 'never' if both tests can never be true).
1366 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'.
1367 BoolTest::mask BoolTest::merge(BoolTest other) const {
1368 const mask res[illegal+1][illegal+1] = {
1369 // eq, gt, of, lt, ne, le, nof, ge, never, illegal
1370 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq
1371 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt
1372 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of
1373 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt
1374 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne
1375 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le
1376 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof
1377 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge
1378 {never, never, never, never, never, never, never, never, never, illegal}, // never
1379 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal
1380 return res[_test][other._test];
1381 }
1382
1383 //=============================================================================
1384 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
1385 uint BoolNode::size_of() const { return sizeof(BoolNode); }
1386
1387 //------------------------------operator==-------------------------------------
1388 bool BoolNode::cmp( const Node &n ) const {
1389 const BoolNode *b = (const BoolNode *)&n; // Cast up
1390 return (_test._test == b->_test._test);
1391 }
1392
1393 //-------------------------------make_predicate--------------------------------
1394 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1395 if (test_value->is_Con()) return test_value;
1396 if (test_value->is_Bool()) return test_value;
1397 if (test_value->is_CMove() &&
1398 test_value->in(CMoveNode::Condition)->is_Bool()) {
1399 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool();
1400 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1401 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1402 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1403 return bol;
1404 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1405 return phase->transform( bol->negate(phase) );
1406 }
1407 // Else fall through. The CMove gets in the way of the test.
1408 // It should be the case that make_predicate(bol->as_int_value()) == bol.
1409 }
1410 Node* cmp = new CmpINode(test_value, phase->intcon(0));
1411 cmp = phase->transform(cmp);
1412 Node* bol = new BoolNode(cmp, BoolTest::ne);
1413 return phase->transform(bol);
1414 }
1415
1416 //--------------------------------as_int_value---------------------------------
1417 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1418 // Inverse to make_predicate. The CMove probably boils down to a Conv2B.
1419 Node* cmov = CMoveNode::make(nullptr, this,
1420 phase->intcon(0), phase->intcon(1),
1421 TypeInt::BOOL);
1422 return phase->transform(cmov);
1423 }
1424
1425 //----------------------------------negate-------------------------------------
1426 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1427 return new BoolNode(in(1), _test.negate());
1428 }
1429
1430 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub
1431 // overflows and we can prove that C is not in the two resulting ranges.
1432 // This optimization is similar to the one performed by CmpUNode::Value().
1433 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op,
1434 int cmp1_op, const TypeInt* cmp2_type) {
1435 // Only optimize eq/ne integer comparison of add/sub
1436 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1437 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) {
1438 // Skip cases were inputs of add/sub are not integers or of bottom type
1439 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int();
1440 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int();
1441 if ((r0 != nullptr) && (r0 != TypeInt::INT) &&
1442 (r1 != nullptr) && (r1 != TypeInt::INT) &&
1443 (cmp2_type != TypeInt::INT)) {
1444 // Compute exact (long) type range of add/sub result
1445 jlong lo_long = r0->_lo;
1446 jlong hi_long = r0->_hi;
1447 if (cmp1_op == Op_AddI) {
1448 lo_long += r1->_lo;
1449 hi_long += r1->_hi;
1450 } else {
1451 lo_long -= r1->_hi;
1452 hi_long -= r1->_lo;
1453 }
1454 // Check for over-/underflow by casting to integer
1455 int lo_int = (int)lo_long;
1456 int hi_int = (int)hi_long;
1457 bool underflow = lo_long != (jlong)lo_int;
1458 bool overflow = hi_long != (jlong)hi_int;
1459 if ((underflow != overflow) && (hi_int < lo_int)) {
1460 // Overflow on one boundary, compute resulting type ranges:
1461 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT]
1462 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
1463 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w);
1464 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w);
1465 // Compare second input of cmp to both type ranges
1466 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type);
1467 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type);
1468 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) {
1469 // The result of the add/sub will never equal cmp2. Replace BoolNode
1470 // by false (0) if it tests for equality and by true (1) otherwise.
1471 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1);
1472 }
1473 }
1474 }
1475 }
1476 return nullptr;
1477 }
1478
1479 static bool is_counted_loop_cmp(Node *cmp) {
1480 Node *n = cmp->in(1)->in(1);
1481 return n != nullptr &&
1482 n->is_Phi() &&
1483 n->in(0) != nullptr &&
1484 n->in(0)->is_CountedLoop() &&
1485 n->in(0)->as_CountedLoop()->phi() == n;
1486 }
1487
1488 //------------------------------Ideal------------------------------------------
1489 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1490 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1491 // This moves the constant to the right. Helps value-numbering.
1492 Node *cmp = in(1);
1493 if( !cmp->is_Sub() ) return nullptr;
1494 int cop = cmp->Opcode();
1495 if( cop == Op_FastLock || cop == Op_FastUnlock ||
1496 cmp->is_SubTypeCheck() || cop == Op_VectorTest ) {
1497 return nullptr;
1498 }
1499 Node *cmp1 = cmp->in(1);
1500 Node *cmp2 = cmp->in(2);
1501 if( !cmp1 ) return nullptr;
1502
1503 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) {
1504 return nullptr;
1505 }
1506
1507 const int cmp1_op = cmp1->Opcode();
1508 const int cmp2_op = cmp2->Opcode();
1509
1510 // Constant on left?
1511 Node *con = cmp1;
1512 // Move constants to the right of compare's to canonicalize.
1513 // Do not muck with Opaque1 nodes, as this indicates a loop
1514 // guard that cannot change shape.
1515 if (con->is_Con() && !cmp2->is_Con() && cmp2_op != Op_OpaqueZeroTripGuard &&
1516 // Because of NaN's, CmpD and CmpF are not commutative
1517 cop != Op_CmpD && cop != Op_CmpF &&
1518 // Protect against swapping inputs to a compare when it is used by a
1519 // counted loop exit, which requires maintaining the loop-limit as in(2)
1520 !is_counted_loop_exit_test() ) {
1521 // Ok, commute the constant to the right of the cmp node.
1522 // Clone the Node, getting a new Node of the same class
1523 cmp = cmp->clone();
1524 // Swap inputs to the clone
1525 cmp->swap_edges(1, 2);
1526 cmp = phase->transform( cmp );
1527 return new BoolNode( cmp, _test.commute() );
1528 }
1529
1530 // Change "bool eq/ne (cmp (cmove (bool tst (cmp2)) 1 0) 0)" into "bool tst/~tst (cmp2)"
1531 if (cop == Op_CmpI &&
1532 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1533 cmp1_op == Op_CMoveI && cmp2->find_int_con(1) == 0) {
1534 // 0 should be on the true branch
1535 if (cmp1->in(CMoveNode::Condition)->is_Bool() &&
1536 cmp1->in(CMoveNode::IfTrue)->find_int_con(1) == 0 &&
1537 cmp1->in(CMoveNode::IfFalse)->find_int_con(0) != 0) {
1538 BoolNode* target = cmp1->in(CMoveNode::Condition)->as_Bool();
1539 return new BoolNode(target->in(1),
1540 (_test._test == BoolTest::eq) ? target->_test._test :
1541 target->_test.negate());
1542 }
1543 }
1544
1545 // Change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1546 if (cop == Op_CmpI &&
1547 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1548 cmp1_op == Op_AndI && cmp2_op == Op_ConI &&
1549 cmp1->in(2)->Opcode() == Op_ConI) {
1550 const TypeInt *t12 = phase->type(cmp2)->isa_int();
1551 const TypeInt *t112 = phase->type(cmp1->in(2))->isa_int();
1552 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1553 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1554 Node *ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1555 return new BoolNode(ncmp, _test.negate());
1556 }
1557 }
1558
1559 // Same for long type: change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1560 if (cop == Op_CmpL &&
1561 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1562 cmp1_op == Op_AndL && cmp2_op == Op_ConL &&
1563 cmp1->in(2)->Opcode() == Op_ConL) {
1564 const TypeLong *t12 = phase->type(cmp2)->isa_long();
1565 const TypeLong *t112 = phase->type(cmp1->in(2))->isa_long();
1566 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1567 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1568 Node *ncmp = phase->transform(new CmpLNode(cmp1, phase->longcon(0)));
1569 return new BoolNode(ncmp, _test.negate());
1570 }
1571 }
1572
1573 // Change "cmp (add X min_jint) (add Y min_jint)" into "cmpu X Y"
1574 // and "cmp (add X min_jint) c" into "cmpu X (c + min_jint)"
1575 if (cop == Op_CmpI &&
1576 cmp1_op == Op_AddI &&
1577 phase->type(cmp1->in(2)) == TypeInt::MIN &&
1578 !is_cloop_condition(this)) {
1579 if (cmp2_op == Op_ConI) {
1580 Node* ncmp2 = phase->intcon(java_add(cmp2->get_int(), min_jint));
1581 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), ncmp2));
1582 return new BoolNode(ncmp, _test._test);
1583 } else if (cmp2_op == Op_AddI &&
1584 phase->type(cmp2->in(2)) == TypeInt::MIN &&
1585 !is_cloop_condition(this)) {
1586 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), cmp2->in(1)));
1587 return new BoolNode(ncmp, _test._test);
1588 }
1589 }
1590
1591 // Change "cmp (add X min_jlong) (add Y min_jlong)" into "cmpu X Y"
1592 // and "cmp (add X min_jlong) c" into "cmpu X (c + min_jlong)"
1593 if (cop == Op_CmpL &&
1594 cmp1_op == Op_AddL &&
1595 phase->type(cmp1->in(2)) == TypeLong::MIN &&
1596 !is_cloop_condition(this)) {
1597 if (cmp2_op == Op_ConL) {
1598 Node* ncmp2 = phase->longcon(java_add(cmp2->get_long(), min_jlong));
1599 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), ncmp2));
1600 return new BoolNode(ncmp, _test._test);
1601 } else if (cmp2_op == Op_AddL &&
1602 phase->type(cmp2->in(2)) == TypeLong::MIN &&
1603 !is_cloop_condition(this)) {
1604 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), cmp2->in(1)));
1605 return new BoolNode(ncmp, _test._test);
1606 }
1607 }
1608
1609 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1610 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the
1611 // test instead.
1612 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1613 if (cmp2_type == nullptr) return nullptr;
1614 Node* j_xor = cmp1;
1615 if( cmp2_type == TypeInt::ZERO &&
1616 cmp1_op == Op_XorI &&
1617 j_xor->in(1) != j_xor && // An xor of itself is dead
1618 phase->type( j_xor->in(1) ) == TypeInt::BOOL &&
1619 phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1620 (_test._test == BoolTest::eq ||
1621 _test._test == BoolTest::ne) ) {
1622 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2));
1623 return new BoolNode( ncmp, _test.negate() );
1624 }
1625
1626 // Change ((x & (m - 1)) u< m) into (m > 0)
1627 // This is the off-by-one variant of ((x & m) u<= m)
1628 if (cop == Op_CmpU &&
1629 _test._test == BoolTest::lt &&
1630 cmp1_op == Op_AndI) {
1631 Node* l = cmp1->in(1);
1632 Node* r = cmp1->in(2);
1633 for (int repeat = 0; repeat < 2; repeat++) {
1634 bool match = r->Opcode() == Op_AddI && r->in(2)->find_int_con(0) == -1 &&
1635 r->in(1) == cmp2;
1636 if (match) {
1637 // arraylength known to be non-negative, so a (arraylength != 0) is sufficient,
1638 // but to be compatible with the array range check pattern, use (arraylength u> 0)
1639 Node* ncmp = cmp2->Opcode() == Op_LoadRange
1640 ? phase->transform(new CmpUNode(cmp2, phase->intcon(0)))
1641 : phase->transform(new CmpINode(cmp2, phase->intcon(0)));
1642 return new BoolNode(ncmp, BoolTest::gt);
1643 } else {
1644 // commute and try again
1645 l = cmp1->in(2);
1646 r = cmp1->in(1);
1647 }
1648 }
1649 }
1650
1651 // Change x u< 1 or x u<= 0 to x == 0
1652 // and x u> 0 or u>= 1 to x != 0
1653 if (cop == Op_CmpU &&
1654 cmp1_op != Op_LoadRange &&
1655 (((_test._test == BoolTest::lt || _test._test == BoolTest::ge) &&
1656 cmp2->find_int_con(-1) == 1) ||
1657 ((_test._test == BoolTest::le || _test._test == BoolTest::gt) &&
1658 cmp2->find_int_con(-1) == 0))) {
1659 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1660 return new BoolNode(ncmp, _test.is_less() ? BoolTest::eq : BoolTest::ne);
1661 }
1662
1663 // Change (arraylength <= 0) or (arraylength == 0)
1664 // into (arraylength u<= 0)
1665 // Also change (arraylength != 0) into (arraylength u> 0)
1666 // The latter version matches the code pattern generated for
1667 // array range checks, which will more likely be optimized later.
1668 if (cop == Op_CmpI &&
1669 cmp1_op == Op_LoadRange &&
1670 cmp2->find_int_con(-1) == 0) {
1671 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) {
1672 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1673 return new BoolNode(ncmp, BoolTest::le);
1674 } else if (_test._test == BoolTest::ne) {
1675 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1676 return new BoolNode(ncmp, BoolTest::gt);
1677 }
1678 }
1679
1680 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1681 // This is a standard idiom for branching on a boolean value.
1682 Node *c2b = cmp1;
1683 if( cmp2_type == TypeInt::ZERO &&
1684 cmp1_op == Op_Conv2B &&
1685 (_test._test == BoolTest::eq ||
1686 _test._test == BoolTest::ne) ) {
1687 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1688 ? (Node*)new CmpINode(c2b->in(1),cmp2)
1689 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1690 );
1691 return new BoolNode( ncmp, _test._test );
1692 }
1693
1694 // Comparing a SubI against a zero is equal to comparing the SubI
1695 // arguments directly. This only works for eq and ne comparisons
1696 // due to possible integer overflow.
1697 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1698 (cop == Op_CmpI) &&
1699 (cmp1_op == Op_SubI) &&
1700 ( cmp2_type == TypeInt::ZERO ) ) {
1701 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2)));
1702 return new BoolNode( ncmp, _test._test );
1703 }
1704
1705 // Same as above but with and AddI of a constant
1706 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1707 cop == Op_CmpI &&
1708 cmp1_op == Op_AddI &&
1709 cmp1->in(2) != nullptr &&
1710 phase->type(cmp1->in(2))->isa_int() &&
1711 phase->type(cmp1->in(2))->is_int()->is_con() &&
1712 cmp2_type == TypeInt::ZERO &&
1713 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape
1714 ) {
1715 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int();
1716 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi)));
1717 return new BoolNode( ncmp, _test._test );
1718 }
1719
1720 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)"
1721 // since zero check of conditional negation of an integer is equal to
1722 // zero check of the integer directly.
1723 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1724 (cop == Op_CmpI) &&
1725 (cmp2_type == TypeInt::ZERO) &&
1726 (cmp1_op == Op_Phi)) {
1727 // There should be a diamond phi with true path at index 1 or 2
1728 PhiNode *phi = cmp1->as_Phi();
1729 int idx_true = phi->is_diamond_phi();
1730 if (idx_true != 0) {
1731 // True input is in(idx_true) while false input is in(3 - idx_true)
1732 Node *tin = phi->in(idx_true);
1733 Node *fin = phi->in(3 - idx_true);
1734 if ((tin->Opcode() == Op_SubI) &&
1735 (phase->type(tin->in(1)) == TypeInt::ZERO) &&
1736 (tin->in(2) == fin)) {
1737 // Found conditional negation at true path, create a new CmpINode without that
1738 Node *ncmp = phase->transform(new CmpINode(fin, cmp2));
1739 return new BoolNode(ncmp, _test._test);
1740 }
1741 if ((fin->Opcode() == Op_SubI) &&
1742 (phase->type(fin->in(1)) == TypeInt::ZERO) &&
1743 (fin->in(2) == tin)) {
1744 // Found conditional negation at false path, create a new CmpINode without that
1745 Node *ncmp = phase->transform(new CmpINode(tin, cmp2));
1746 return new BoolNode(ncmp, _test._test);
1747 }
1748 }
1749 }
1750
1751 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the
1752 // most general case because negating 0x80000000 does nothing. Needed for
1753 // the CmpF3/SubI/CmpI idiom.
1754 if( cop == Op_CmpI &&
1755 cmp1_op == Op_SubI &&
1756 cmp2_type == TypeInt::ZERO &&
1757 phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1758 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1759 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2));
1760 return new BoolNode( ncmp, _test.commute() );
1761 }
1762
1763 // Try to optimize signed integer comparison
1764 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type);
1765
1766 // The transformation below is not valid for either signed or unsigned
1767 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1768 // This transformation can be resurrected when we are able to
1769 // make inferences about the range of values being subtracted from
1770 // (or added to) relative to the wraparound point.
1771 //
1772 // // Remove +/-1's if possible.
1773 // // "X <= Y-1" becomes "X < Y"
1774 // // "X+1 <= Y" becomes "X < Y"
1775 // // "X < Y+1" becomes "X <= Y"
1776 // // "X-1 < Y" becomes "X <= Y"
1777 // // Do not this to compares off of the counted-loop-end. These guys are
1778 // // checking the trip counter and they want to use the post-incremented
1779 // // counter. If they use the PRE-incremented counter, then the counter has
1780 // // to be incremented in a private block on a loop backedge.
1781 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1782 // return nullptr;
1783 // #ifndef PRODUCT
1784 // // Do not do this in a wash GVN pass during verification.
1785 // // Gets triggered by too many simple optimizations to be bothered with
1786 // // re-trying it again and again.
1787 // if( !phase->allow_progress() ) return nullptr;
1788 // #endif
1789 // // Not valid for unsigned compare because of corner cases in involving zero.
1790 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1791 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1792 // // "0 <=u Y" is always true).
1793 // if( cmp->Opcode() == Op_CmpU ) return nullptr;
1794 // int cmp2_op = cmp2->Opcode();
1795 // if( _test._test == BoolTest::le ) {
1796 // if( cmp1_op == Op_AddI &&
1797 // phase->type( cmp1->in(2) ) == TypeInt::ONE )
1798 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1799 // else if( cmp2_op == Op_AddI &&
1800 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1801 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1802 // } else if( _test._test == BoolTest::lt ) {
1803 // if( cmp1_op == Op_AddI &&
1804 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1805 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1806 // else if( cmp2_op == Op_AddI &&
1807 // phase->type( cmp2->in(2) ) == TypeInt::ONE )
1808 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1809 // }
1810 }
1811
1812 //------------------------------Value------------------------------------------
1813 // Change ((x & m) u<= m) or ((m & x) u<= m) to always true
1814 // Same with ((x & m) u< m+1) and ((m & x) u< m+1)
1815 const Type* BoolNode::Value_cmpu_and_mask(PhaseValues* phase) const {
1816 Node* cmp = in(1);
1817 if (cmp != nullptr && cmp->Opcode() == Op_CmpU) {
1818 Node* cmp1 = cmp->in(1);
1819 Node* cmp2 = cmp->in(2);
1820
1821 if (cmp1->Opcode() == Op_AndI) {
1822 Node* bound = nullptr;
1823 if (_test._test == BoolTest::le) {
1824 bound = cmp2;
1825 } else if (_test._test == BoolTest::lt && cmp2->Opcode() == Op_AddI && cmp2->in(2)->find_int_con(0) == 1) {
1826 bound = cmp2->in(1);
1827 }
1828
1829 if (cmp1->in(2) == bound || cmp1->in(1) == bound) {
1830 return TypeInt::ONE;
1831 }
1832 }
1833 }
1834
1835 return nullptr;
1836 }
1837
1838 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
1839 // based on local information. If the input is constant, do it.
1840 const Type* BoolNode::Value(PhaseGVN* phase) const {
1841 const Type* t = Value_cmpu_and_mask(phase);
1842 if (t != nullptr) {
1843 return t;
1844 }
1845
1846 return _test.cc2logical( phase->type( in(1) ) );
1847 }
1848
1849 #ifndef PRODUCT
1850 //------------------------------dump_spec--------------------------------------
1851 // Dump special per-node info
1852 void BoolNode::dump_spec(outputStream *st) const {
1853 st->print("[");
1854 _test.dump_on(st);
1855 st->print("]");
1856 }
1857 #endif
1858
1859 //----------------------is_counted_loop_exit_test------------------------------
1860 // Returns true if node is used by a counted loop node.
1861 bool BoolNode::is_counted_loop_exit_test() {
1862 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
1863 Node* use = fast_out(i);
1864 if (use->is_CountedLoopEnd()) {
1865 return true;
1866 }
1867 }
1868 return false;
1869 }
1870
1871 //=============================================================================
1872 //------------------------------Value------------------------------------------
1873 const Type* AbsNode::Value(PhaseGVN* phase) const {
1874 const Type* t1 = phase->type(in(1));
1875 if (t1 == Type::TOP) return Type::TOP;
1876
1877 switch (t1->base()) {
1878 case Type::Int: {
1879 const TypeInt* ti = t1->is_int();
1880 if (ti->is_con()) {
1881 return TypeInt::make(uabs(ti->get_con()));
1882 }
1883 break;
1884 }
1885 case Type::Long: {
1886 const TypeLong* tl = t1->is_long();
1887 if (tl->is_con()) {
1888 return TypeLong::make(uabs(tl->get_con()));
1889 }
1890 break;
1891 }
1892 case Type::FloatCon:
1893 return TypeF::make(abs(t1->getf()));
1894 case Type::DoubleCon:
1895 return TypeD::make(abs(t1->getd()));
1896 default:
1897 break;
1898 }
1899
1900 return bottom_type();
1901 }
1902
1903 //------------------------------Identity----------------------------------------
1904 Node* AbsNode::Identity(PhaseGVN* phase) {
1905 Node* in1 = in(1);
1906 // No need to do abs for non-negative values
1907 if (phase->type(in1)->higher_equal(TypeInt::POS) ||
1908 phase->type(in1)->higher_equal(TypeLong::POS)) {
1909 return in1;
1910 }
1911 // Convert "abs(abs(x))" into "abs(x)"
1912 if (in1->Opcode() == Opcode()) {
1913 return in1;
1914 }
1915 return this;
1916 }
1917
1918 //------------------------------Ideal------------------------------------------
1919 Node* AbsNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1920 Node* in1 = in(1);
1921 // Convert "abs(0-x)" into "abs(x)"
1922 if (in1->is_Sub() && phase->type(in1->in(1))->is_zero_type()) {
1923 set_req_X(1, in1->in(2), phase);
1924 return this;
1925 }
1926 return nullptr;
1927 }
1928
1929 //=============================================================================
1930 //------------------------------Value------------------------------------------
1931 // Compute sqrt
1932 const Type* SqrtDNode::Value(PhaseGVN* phase) const {
1933 const Type *t1 = phase->type( in(1) );
1934 if( t1 == Type::TOP ) return Type::TOP;
1935 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1936 double d = t1->getd();
1937 if( d < 0.0 ) return Type::DOUBLE;
1938 return TypeD::make( sqrt( d ) );
1939 }
1940
1941 const Type* SqrtFNode::Value(PhaseGVN* phase) const {
1942 const Type *t1 = phase->type( in(1) );
1943 if( t1 == Type::TOP ) return Type::TOP;
1944 if( t1->base() != Type::FloatCon ) return Type::FLOAT;
1945 float f = t1->getf();
1946 if( f < 0.0f ) return Type::FLOAT;
1947 return TypeF::make( (float)sqrt( (double)f ) );
1948 }
1949
1950 const Type* ReverseINode::Value(PhaseGVN* phase) const {
1951 const Type *t1 = phase->type( in(1) );
1952 if (t1 == Type::TOP) {
1953 return Type::TOP;
1954 }
1955 const TypeInt* t1int = t1->isa_int();
1956 if (t1int && t1int->is_con()) {
1957 jint res = reverse_bits(t1int->get_con());
1958 return TypeInt::make(res);
1959 }
1960 return bottom_type();
1961 }
1962
1963 const Type* ReverseLNode::Value(PhaseGVN* phase) const {
1964 const Type *t1 = phase->type( in(1) );
1965 if (t1 == Type::TOP) {
1966 return Type::TOP;
1967 }
1968 const TypeLong* t1long = t1->isa_long();
1969 if (t1long && t1long->is_con()) {
1970 jlong res = reverse_bits(t1long->get_con());
1971 return TypeLong::make(res);
1972 }
1973 return bottom_type();
1974 }
1975
1976 Node* ReverseINode::Identity(PhaseGVN* phase) {
1977 if (in(1)->Opcode() == Op_ReverseI) {
1978 return in(1)->in(1);
1979 }
1980 return this;
1981 }
1982
1983 Node* ReverseLNode::Identity(PhaseGVN* phase) {
1984 if (in(1)->Opcode() == Op_ReverseL) {
1985 return in(1)->in(1);
1986 }
1987 return this;
1988 }