1 /*
2 * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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(PhaseTransform *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 //------------------------------Ideal------------------------------------------
156 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){
157 Node *in1 = in(1);
158 Node *in2 = in(2);
159 uint op1 = in1->Opcode();
160 uint op2 = in2->Opcode();
161
162 #ifdef ASSERT
163 // Check for dead loop
164 if ((in1 == this) || (in2 == this) ||
165 ((op1 == Op_AddI || op1 == Op_SubI) &&
166 ((in1->in(1) == this) || (in1->in(2) == this) ||
167 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
168 assert(false, "dead loop in SubINode::Ideal");
169 }
170 #endif
171
172 const Type *t2 = phase->type( in2 );
173 if( t2 == Type::TOP ) return nullptr;
174 // Convert "x-c0" into "x+ -c0".
175 if( t2->base() == Type::Int ){ // Might be bottom or top...
176 const TypeInt *i = t2->is_int();
177 if( i->is_con() )
178 return new AddINode(in1, phase->intcon(java_negate(i->get_con())));
179 }
180
181 // Convert "(x+c0) - y" into (x-y) + c0"
182 // Do not collapse (x+c0)-y if "+" is a loop increment or
183 // if "y" is a loop induction variable.
184 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) {
185 const Type *tadd = phase->type( in1->in(2) );
186 if( tadd->singleton() && tadd != Type::TOP ) {
187 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 ));
188 return new AddINode( sub2, in1->in(2) );
189 }
190 }
191
192 // Convert "x - (y+c0)" into "(x-y) - c0" AND
193 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
194 // Need the same check as in above optimization but reversed.
195 if (op2 == Op_AddI
196 && ok_to_convert(in2, in1)
197 && in2->in(2)->Opcode() == Op_ConI) {
198 jint c0 = phase->type(in2->in(2))->isa_int()->get_con();
199 Node* in21 = in2->in(1);
200 if (in1->Opcode() == Op_ConI) {
201 // Match c1
202 jint c1 = phase->type(in1)->isa_int()->get_con();
203 Node* sub2 = phase->intcon(java_subtract(c1, c0));
204 return new SubINode(sub2, in21);
205 } else {
206 // Match x
207 Node* sub2 = phase->transform(new SubINode(in1, in21));
208 Node* neg_c0 = phase->intcon(java_negate(c0));
209 return new AddINode(sub2, neg_c0);
210 }
211 }
212
213 const Type *t1 = phase->type( in1 );
214 if( t1 == Type::TOP ) return nullptr;
215
216 #ifdef ASSERT
217 // Check for dead loop
218 if ((op2 == Op_AddI || op2 == Op_SubI) &&
219 ((in2->in(1) == this) || (in2->in(2) == this) ||
220 (in2->in(1) == in2) || (in2->in(2) == in2))) {
221 assert(false, "dead loop in SubINode::Ideal");
222 }
223 #endif
224
225 // Convert "x - (x+y)" into "-y"
226 if (op2 == Op_AddI && in1 == in2->in(1)) {
227 return new SubINode(phase->intcon(0), in2->in(2));
228 }
229 // Convert "(x-y) - x" into "-y"
230 if (op1 == Op_SubI && in1->in(1) == in2) {
231 return new SubINode(phase->intcon(0), in1->in(2));
232 }
233 // Convert "x - (y+x)" into "-y"
234 if (op2 == Op_AddI && in1 == in2->in(2)) {
235 return new SubINode(phase->intcon(0), in2->in(1));
236 }
237
238 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity().
239 if (t1 == TypeInt::ZERO && op2 == Op_SubI && phase->type(in2->in(1)) != TypeInt::ZERO) {
240 return new SubINode(in2->in(2), in2->in(1));
241 }
242
243 // Convert "0 - (x+con)" into "-con-x"
244 jint con;
245 if( t1 == TypeInt::ZERO && op2 == Op_AddI &&
246 (con = in2->in(2)->find_int_con(0)) != 0 )
247 return new SubINode( phase->intcon(-con), in2->in(1) );
248
249 // Convert "(X+A) - (X+B)" into "A - B"
250 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) )
251 return new SubINode( in1->in(2), in2->in(2) );
252
253 // Convert "(A+X) - (B+X)" into "A - B"
254 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) )
255 return new SubINode( in1->in(1), in2->in(1) );
256
257 // Convert "(A+X) - (X+B)" into "A - B"
258 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) )
259 return new SubINode( in1->in(1), in2->in(2) );
260
261 // Convert "(X+A) - (B+X)" into "A - B"
262 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) )
263 return new SubINode( in1->in(2), in2->in(1) );
264
265 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally
266 // nicer to optimize than subtract.
267 if( op2 == Op_SubI && in2->outcnt() == 1) {
268 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) );
269 return new SubINode( add1, in2->in(1) );
270 }
271
272 // Associative
273 if (op1 == Op_MulI && op2 == Op_MulI) {
274 Node* sub_in1 = nullptr;
275 Node* sub_in2 = nullptr;
276 Node* mul_in = nullptr;
277
278 if (in1->in(1) == in2->in(1)) {
279 // Convert "a*b-a*c into a*(b-c)
280 sub_in1 = in1->in(2);
281 sub_in2 = in2->in(2);
282 mul_in = in1->in(1);
283 } else if (in1->in(2) == in2->in(1)) {
284 // Convert a*b-b*c into b*(a-c)
285 sub_in1 = in1->in(1);
286 sub_in2 = in2->in(2);
287 mul_in = in1->in(2);
288 } else if (in1->in(2) == in2->in(2)) {
289 // Convert a*c-b*c into (a-b)*c
290 sub_in1 = in1->in(1);
291 sub_in2 = in2->in(1);
292 mul_in = in1->in(2);
293 } else if (in1->in(1) == in2->in(2)) {
294 // Convert a*b-c*a into a*(b-c)
295 sub_in1 = in1->in(2);
296 sub_in2 = in2->in(1);
297 mul_in = in1->in(1);
298 }
299
300 if (mul_in != nullptr) {
301 Node* sub = phase->transform(new SubINode(sub_in1, sub_in2));
302 return new MulINode(mul_in, sub);
303 }
304 }
305
306 // Convert "0-(A>>31)" into "(A>>>31)"
307 if ( op2 == Op_RShiftI ) {
308 Node *in21 = in2->in(1);
309 Node *in22 = in2->in(2);
310 const TypeInt *zero = phase->type(in1)->isa_int();
311 const TypeInt *t21 = phase->type(in21)->isa_int();
312 const TypeInt *t22 = phase->type(in22)->isa_int();
313 if ( t21 && t22 && zero == TypeInt::ZERO && t22->is_con(31) ) {
314 return new URShiftINode(in21, in22);
315 }
316 }
317
318 return nullptr;
319 }
320
321 //------------------------------sub--------------------------------------------
322 // A subtract node differences it's two inputs.
323 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const {
324 const TypeInt *r0 = t1->is_int(); // Handy access
325 const TypeInt *r1 = t2->is_int();
326 int32_t lo = java_subtract(r0->_lo, r1->_hi);
327 int32_t hi = java_subtract(r0->_hi, r1->_lo);
328
329 // We next check for 32-bit overflow.
330 // If that happens, we just assume all integers are possible.
331 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
332 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
333 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
334 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
335 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen));
336 else // Overflow; assume all integers
337 return TypeInt::INT;
338 }
339
340 //=============================================================================
341 //------------------------------Ideal------------------------------------------
342 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
343 Node *in1 = in(1);
344 Node *in2 = in(2);
345 uint op1 = in1->Opcode();
346 uint op2 = in2->Opcode();
347
348 #ifdef ASSERT
349 // Check for dead loop
350 if ((in1 == this) || (in2 == this) ||
351 ((op1 == Op_AddL || op1 == Op_SubL) &&
352 ((in1->in(1) == this) || (in1->in(2) == this) ||
353 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
354 assert(false, "dead loop in SubLNode::Ideal");
355 }
356 #endif
357
358 if( phase->type( in2 ) == Type::TOP ) return nullptr;
359 const TypeLong *i = phase->type( in2 )->isa_long();
360 // Convert "x-c0" into "x+ -c0".
361 if( i && // Might be bottom or top...
362 i->is_con() )
363 return new AddLNode(in1, phase->longcon(-i->get_con()));
364
365 // Convert "(x+c0) - y" into (x-y) + c0"
366 // Do not collapse (x+c0)-y if "+" is a loop increment or
367 // if "y" is a loop induction variable.
368 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) {
369 Node *in11 = in1->in(1);
370 const Type *tadd = phase->type( in1->in(2) );
371 if( tadd->singleton() && tadd != Type::TOP ) {
372 Node *sub2 = phase->transform( new SubLNode( in11, in2 ));
373 return new AddLNode( sub2, in1->in(2) );
374 }
375 }
376
377 // Convert "x - (y+c0)" into "(x-y) - c0" AND
378 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
379 // Need the same check as in above optimization but reversed.
380 if (op2 == Op_AddL
381 && ok_to_convert(in2, in1)
382 && in2->in(2)->Opcode() == Op_ConL) {
383 jlong c0 = phase->type(in2->in(2))->isa_long()->get_con();
384 Node* in21 = in2->in(1);
385 if (in1->Opcode() == Op_ConL) {
386 // Match c1
387 jlong c1 = phase->type(in1)->isa_long()->get_con();
388 Node* sub2 = phase->longcon(java_subtract(c1, c0));
389 return new SubLNode(sub2, in21);
390 } else {
391 Node* sub2 = phase->transform(new SubLNode(in1, in21));
392 Node* neg_c0 = phase->longcon(-c0);
393 return new AddLNode(sub2, neg_c0);
394 }
395 }
396
397 const Type *t1 = phase->type( in1 );
398 if( t1 == Type::TOP ) return nullptr;
399
400 #ifdef ASSERT
401 // Check for dead loop
402 if ((op2 == Op_AddL || op2 == Op_SubL) &&
403 ((in2->in(1) == this) || (in2->in(2) == this) ||
404 (in2->in(1) == in2) || (in2->in(2) == in2))) {
405 assert(false, "dead loop in SubLNode::Ideal");
406 }
407 #endif
408
409 // Convert "x - (x+y)" into "-y"
410 if (op2 == Op_AddL && in1 == in2->in(1)) {
411 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(2));
412 }
413 // Convert "(x-y) - x" into "-y"
414 if (op1 == Op_SubL && in1->in(1) == in2) {
415 return new SubLNode(phase->makecon(TypeLong::ZERO), in1->in(2));
416 }
417 // Convert "x - (y+x)" into "-y"
418 if (op2 == Op_AddL && in1 == in2->in(2)) {
419 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(1));
420 }
421
422 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity.
423 if (t1 == TypeLong::ZERO && op2 == Op_SubL && phase->type(in2->in(1)) != TypeLong::ZERO) {
424 return new SubLNode(in2->in(2), in2->in(1));
425 }
426
427 // Convert "(X+A) - (X+B)" into "A - B"
428 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) )
429 return new SubLNode( in1->in(2), in2->in(2) );
430
431 // Convert "(A+X) - (B+X)" into "A - B"
432 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) )
433 return new SubLNode( in1->in(1), in2->in(1) );
434
435 // Convert "(A+X) - (X+B)" into "A - B"
436 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(1) )
437 return new SubLNode( in1->in(1), in2->in(2) );
438
439 // Convert "(X+A) - (B+X)" into "A - B"
440 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(2) )
441 return new SubLNode( in1->in(2), in2->in(1) );
442
443 // Convert "A-(B-C)" into (A+C)-B"
444 if( op2 == Op_SubL && in2->outcnt() == 1) {
445 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) );
446 return new SubLNode( add1, in2->in(1) );
447 }
448
449 // Associative
450 if (op1 == Op_MulL && op2 == Op_MulL) {
451 Node* sub_in1 = nullptr;
452 Node* sub_in2 = nullptr;
453 Node* mul_in = nullptr;
454
455 if (in1->in(1) == in2->in(1)) {
456 // Convert "a*b-a*c into a*(b+c)
457 sub_in1 = in1->in(2);
458 sub_in2 = in2->in(2);
459 mul_in = in1->in(1);
460 } else if (in1->in(2) == in2->in(1)) {
461 // Convert a*b-b*c into b*(a-c)
462 sub_in1 = in1->in(1);
463 sub_in2 = in2->in(2);
464 mul_in = in1->in(2);
465 } else if (in1->in(2) == in2->in(2)) {
466 // Convert a*c-b*c into (a-b)*c
467 sub_in1 = in1->in(1);
468 sub_in2 = in2->in(1);
469 mul_in = in1->in(2);
470 } else if (in1->in(1) == in2->in(2)) {
471 // Convert a*b-c*a into a*(b-c)
472 sub_in1 = in1->in(2);
473 sub_in2 = in2->in(1);
474 mul_in = in1->in(1);
475 }
476
477 if (mul_in != nullptr) {
478 Node* sub = phase->transform(new SubLNode(sub_in1, sub_in2));
479 return new MulLNode(mul_in, sub);
480 }
481 }
482
483 // Convert "0L-(A>>63)" into "(A>>>63)"
484 if ( op2 == Op_RShiftL ) {
485 Node *in21 = in2->in(1);
486 Node *in22 = in2->in(2);
487 const TypeLong *zero = phase->type(in1)->isa_long();
488 const TypeLong *t21 = phase->type(in21)->isa_long();
489 const TypeInt *t22 = phase->type(in22)->isa_int();
490 if ( t21 && t22 && zero == TypeLong::ZERO && t22->is_con(63) ) {
491 return new URShiftLNode(in21, in22);
492 }
493 }
494
495 return nullptr;
496 }
497
498 //------------------------------sub--------------------------------------------
499 // A subtract node differences it's two inputs.
500 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const {
501 const TypeLong *r0 = t1->is_long(); // Handy access
502 const TypeLong *r1 = t2->is_long();
503 jlong lo = java_subtract(r0->_lo, r1->_hi);
504 jlong hi = java_subtract(r0->_hi, r1->_lo);
505
506 // We next check for 32-bit overflow.
507 // If that happens, we just assume all integers are possible.
508 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
509 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
510 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
511 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
512 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen));
513 else // Overflow; assume all integers
514 return TypeLong::LONG;
515 }
516
517 //=============================================================================
518 //------------------------------Value------------------------------------------
519 // A subtract node differences its two inputs.
520 const Type* SubFPNode::Value(PhaseGVN* phase) const {
521 const Node* in1 = in(1);
522 const Node* in2 = in(2);
523 // Either input is TOP ==> the result is TOP
524 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
525 if( t1 == Type::TOP ) return Type::TOP;
526 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
527 if( t2 == Type::TOP ) return Type::TOP;
528
529 // if both operands are infinity of same sign, the result is NaN; do
530 // not replace with zero
531 if (t1->is_finite() && t2->is_finite() && in1 == in2) {
532 return add_id();
533 }
534
535 // Either input is BOTTOM ==> the result is the local BOTTOM
536 const Type *bot = bottom_type();
537 if( (t1 == bot) || (t2 == bot) ||
538 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
539 return bot;
540
541 return sub(t1,t2); // Local flavor of type subtraction
542 }
543
544
545 //=============================================================================
546 //------------------------------Ideal------------------------------------------
547 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
548 const Type *t2 = phase->type( in(2) );
549 // Convert "x-c0" into "x+ -c0".
550 if( t2->base() == Type::FloatCon ) { // Might be bottom or top...
551 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) );
552 }
553
554 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes
555 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0.
556 //if( phase->type(in(1)) == TypeF::ZERO )
557 //return new (phase->C, 2) NegFNode(in(2));
558
559 return nullptr;
560 }
561
562 //------------------------------sub--------------------------------------------
563 // A subtract node differences its two inputs.
564 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const {
565 // no folding if one of operands is infinity or NaN, do not do constant folding
566 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) {
567 return TypeF::make( t1->getf() - t2->getf() );
568 }
569 else if( g_isnan(t1->getf()) ) {
570 return t1;
571 }
572 else if( g_isnan(t2->getf()) ) {
573 return t2;
574 }
575 else {
576 return Type::FLOAT;
577 }
578 }
579
580 //=============================================================================
581 //------------------------------Ideal------------------------------------------
582 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){
583 const Type *t2 = phase->type( in(2) );
584 // Convert "x-c0" into "x+ -c0".
585 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top...
586 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) );
587 }
588
589 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes
590 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0.
591 //if( phase->type(in(1)) == TypeD::ZERO )
592 //return new (phase->C, 2) NegDNode(in(2));
593
594 return nullptr;
595 }
596
597 //------------------------------sub--------------------------------------------
598 // A subtract node differences its two inputs.
599 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const {
600 // no folding if one of operands is infinity or NaN, do not do constant folding
601 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) {
602 return TypeD::make( t1->getd() - t2->getd() );
603 }
604 else if( g_isnan(t1->getd()) ) {
605 return t1;
606 }
607 else if( g_isnan(t2->getd()) ) {
608 return t2;
609 }
610 else {
611 return Type::DOUBLE;
612 }
613 }
614
615 //=============================================================================
616 //------------------------------Idealize---------------------------------------
617 // Unlike SubNodes, compare must still flatten return value to the
618 // range -1, 0, 1.
619 // And optimizations like those for (X + Y) - X fail if overflow happens.
620 Node* CmpNode::Identity(PhaseGVN* phase) {
621 return this;
622 }
623
624 CmpNode *CmpNode::make(Node *in1, Node *in2, BasicType bt, bool unsigned_comp) {
625 switch (bt) {
626 case T_INT:
627 if (unsigned_comp) {
628 return new CmpUNode(in1, in2);
629 }
630 return new CmpINode(in1, in2);
631 case T_LONG:
632 if (unsigned_comp) {
633 return new CmpULNode(in1, in2);
634 }
635 return new CmpLNode(in1, in2);
636 default:
637 fatal("Not implemented for %s", type2name(bt));
638 }
639 return nullptr;
640 }
641
642 //=============================================================================
643 //------------------------------cmp--------------------------------------------
644 // Simplify a CmpI (compare 2 integers) node, based on local information.
645 // If both inputs are constants, compare them.
646 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const {
647 const TypeInt *r0 = t1->is_int(); // Handy access
648 const TypeInt *r1 = t2->is_int();
649
650 if( r0->_hi < r1->_lo ) // Range is always low?
651 return TypeInt::CC_LT;
652 else if( r0->_lo > r1->_hi ) // Range is always high?
653 return TypeInt::CC_GT;
654
655 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
656 assert(r0->get_con() == r1->get_con(), "must be equal");
657 return TypeInt::CC_EQ; // Equal results.
658 } else if( r0->_hi == r1->_lo ) // Range is never high?
659 return TypeInt::CC_LE;
660 else if( r0->_lo == r1->_hi ) // Range is never low?
661 return TypeInt::CC_GE;
662 return TypeInt::CC; // else use worst case results
663 }
664
665 const Type* CmpINode::Value(PhaseGVN* phase) const {
666 Node* in1 = in(1);
667 Node* in2 = in(2);
668 // If this test is the zero trip guard for a main or post loop, check whether, with the opaque node removed, the test
669 // would constant fold so the loop is never entered. If so return the type of the test without the opaque node removed:
670 // make the loop unreachable.
671 // The reason for this is that the iv phi captures the bounds of the loop and if the loop becomes unreachable, it can
672 // become top. In that case, the loop must be removed.
673 // This is safe because:
674 // - as optimizations proceed, the range of iterations executed by the main loop narrows. If no iterations remain, then
675 // we're done with optimizations for that loop.
676 // - the post loop is initially not reachable but as long as there's a main loop, the zero trip guard for the post
677 // 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
678 // loop is removed, there's no need to preserve the zero trip guard for the post loop anymore.
679 if (in1 != nullptr && in2 != nullptr) {
680 uint input = 0;
681 Node* cmp = nullptr;
682 BoolTest::mask test;
683 if (in1->Opcode() == Op_OpaqueZeroTripGuard && phase->type(in1) != Type::TOP) {
684 cmp = new CmpINode(in1->in(1), in2);
685 test = ((OpaqueZeroTripGuardNode*)in1)->_loop_entered_mask;
686 }
687 if (in2->Opcode() == Op_OpaqueZeroTripGuard && phase->type(in2) != Type::TOP) {
688 assert(cmp == nullptr, "A cmp with 2 OpaqueZeroTripGuard inputs");
689 cmp = new CmpINode(in1, in2->in(1));
690 test = ((OpaqueZeroTripGuardNode*)in2)->_loop_entered_mask;
691 }
692 if (cmp != nullptr) {
693 const Type* cmp_t = cmp->Value(phase);
694 const Type* t = BoolTest(test).cc2logical(cmp_t);
695 cmp->destruct(phase);
696 if (t == TypeInt::ZERO) {
697 return cmp_t;
698 }
699 }
700 }
701
702 return SubNode::Value(phase);
703 }
704
705
706 // Simplify a CmpU (compare 2 integers) node, based on local information.
707 // If both inputs are constants, compare them.
708 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const {
709 assert(!t1->isa_ptr(), "obsolete usage of CmpU");
710
711 // comparing two unsigned ints
712 const TypeInt *r0 = t1->is_int(); // Handy access
713 const TypeInt *r1 = t2->is_int();
714
715 // Current installed version
716 // Compare ranges for non-overlap
717 juint lo0 = r0->_lo;
718 juint hi0 = r0->_hi;
719 juint lo1 = r1->_lo;
720 juint hi1 = r1->_hi;
721
722 // If either one has both negative and positive values,
723 // it therefore contains both 0 and -1, and since [0..-1] is the
724 // full unsigned range, the type must act as an unsigned bottom.
725 bool bot0 = ((jint)(lo0 ^ hi0) < 0);
726 bool bot1 = ((jint)(lo1 ^ hi1) < 0);
727
728 if (bot0 || bot1) {
729 // All unsigned values are LE -1 and GE 0.
730 if (lo0 == 0 && hi0 == 0) {
731 return TypeInt::CC_LE; // 0 <= bot
732 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) {
733 return TypeInt::CC_GE; // -1 >= bot
734 } else if (lo1 == 0 && hi1 == 0) {
735 return TypeInt::CC_GE; // bot >= 0
736 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) {
737 return TypeInt::CC_LE; // bot <= -1
738 }
739 } else {
740 // We can use ranges of the form [lo..hi] if signs are the same.
741 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
742 // results are reversed, '-' > '+' for unsigned compare
743 if (hi0 < lo1) {
744 return TypeInt::CC_LT; // smaller
745 } else if (lo0 > hi1) {
746 return TypeInt::CC_GT; // greater
747 } else if (hi0 == lo1 && lo0 == hi1) {
748 return TypeInt::CC_EQ; // Equal results
749 } else if (lo0 >= hi1) {
750 return TypeInt::CC_GE;
751 } else if (hi0 <= lo1) {
752 // Check for special case in Hashtable::get. (See below.)
753 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
754 return TypeInt::CC_LT;
755 return TypeInt::CC_LE;
756 }
757 }
758 // Check for special case in Hashtable::get - the hash index is
759 // mod'ed to the table size so the following range check is useless.
760 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have
761 // to be positive.
762 // (This is a gross hack, since the sub method never
763 // looks at the structure of the node in any other case.)
764 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
765 return TypeInt::CC_LT;
766 return TypeInt::CC; // else use worst case results
767 }
768
769 const Type* CmpUNode::Value(PhaseGVN* phase) const {
770 const Type* t = SubNode::Value_common(phase);
771 if (t != nullptr) {
772 return t;
773 }
774 const Node* in1 = in(1);
775 const Node* in2 = in(2);
776 const Type* t1 = phase->type(in1);
777 const Type* t2 = phase->type(in2);
778 assert(t1->isa_int(), "CmpU has only Int type inputs");
779 if (t2 == TypeInt::INT) { // Compare to bottom?
780 return bottom_type();
781 }
782
783 const Type* t_sub = sub(t1, t2); // compare based on immediate inputs
784
785 uint in1_op = in1->Opcode();
786 if (in1_op == Op_AddI || in1_op == Op_SubI) {
787 // The problem rise when result of AddI(SubI) may overflow
788 // signed integer value. Let say the input type is
789 // [256, maxint] then +128 will create 2 ranges due to
790 // overflow: [minint, minint+127] and [384, maxint].
791 // But C2 type system keep only 1 type range and as result
792 // it use general [minint, maxint] for this case which we
793 // can't optimize.
794 //
795 // Make 2 separate type ranges based on types of AddI(SubI) inputs
796 // and compare results of their compare. If results are the same
797 // CmpU node can be optimized.
798 const Node* in11 = in1->in(1);
799 const Node* in12 = in1->in(2);
800 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11);
801 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12);
802 // Skip cases when input types are top or bottom.
803 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) &&
804 (t12 != Type::TOP) && (t12 != TypeInt::INT)) {
805 const TypeInt *r0 = t11->is_int();
806 const TypeInt *r1 = t12->is_int();
807 jlong lo_r0 = r0->_lo;
808 jlong hi_r0 = r0->_hi;
809 jlong lo_r1 = r1->_lo;
810 jlong hi_r1 = r1->_hi;
811 if (in1_op == Op_SubI) {
812 jlong tmp = hi_r1;
813 hi_r1 = -lo_r1;
814 lo_r1 = -tmp;
815 // Note, for substructing [minint,x] type range
816 // long arithmetic provides correct overflow answer.
817 // The confusion come from the fact that in 32-bit
818 // -minint == minint but in 64-bit -minint == maxint+1.
819 }
820 jlong lo_long = lo_r0 + lo_r1;
821 jlong hi_long = hi_r0 + hi_r1;
822 int lo_tr1 = min_jint;
823 int hi_tr1 = (int)hi_long;
824 int lo_tr2 = (int)lo_long;
825 int hi_tr2 = max_jint;
826 bool underflow = lo_long != (jlong)lo_tr2;
827 bool overflow = hi_long != (jlong)hi_tr1;
828 // Use sub(t1, t2) when there is no overflow (one type range)
829 // or when both overflow and underflow (too complex).
830 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) {
831 // Overflow only on one boundary, compare 2 separate type ranges.
832 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
833 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w);
834 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w);
835 const TypeInt* cmp1 = sub(tr1, t2)->is_int();
836 const TypeInt* cmp2 = sub(tr2, t2)->is_int();
837 // Compute union, so that cmp handles all possible results from the two cases
838 const Type* t_cmp = cmp1->meet(cmp2);
839 // Pick narrowest type, based on overflow computation and on immediate inputs
840 return t_sub->filter(t_cmp);
841 }
842 }
843 }
844
845 return t_sub;
846 }
847
848 bool CmpUNode::is_index_range_check() const {
849 // Check for the "(X ModI Y) CmpU Y" shape
850 return (in(1)->Opcode() == Op_ModI &&
851 in(1)->in(2)->eqv_uncast(in(2)));
852 }
853
854 //------------------------------Idealize---------------------------------------
855 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
856 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) {
857 switch (in(1)->Opcode()) {
858 case Op_CmpU3: // Collapse a CmpU3/CmpI into a CmpU
859 return new CmpUNode(in(1)->in(1),in(1)->in(2));
860 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL
861 return new CmpLNode(in(1)->in(1),in(1)->in(2));
862 case Op_CmpUL3: // Collapse a CmpUL3/CmpI into a CmpUL
863 return new CmpULNode(in(1)->in(1),in(1)->in(2));
864 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF
865 return new CmpFNode(in(1)->in(1),in(1)->in(2));
866 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD
867 return new CmpDNode(in(1)->in(1),in(1)->in(2));
868 //case Op_SubI:
869 // If (x - y) cannot overflow, then ((x - y) <?> 0)
870 // can be turned into (x <?> y).
871 // This is handled (with more general cases) by Ideal_sub_algebra.
872 }
873 }
874 return nullptr; // No change
875 }
876
877 Node *CmpLNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
878 const TypeLong *t2 = phase->type(in(2))->isa_long();
879 if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) {
880 const jlong con = t2->get_con();
881 if (con >= min_jint && con <= max_jint) {
882 return new CmpINode(in(1)->in(1), phase->intcon((jint)con));
883 }
884 }
885 return nullptr;
886 }
887
888 //=============================================================================
889 // Simplify a CmpL (compare 2 longs ) node, based on local information.
890 // If both inputs are constants, compare them.
891 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const {
892 const TypeLong *r0 = t1->is_long(); // Handy access
893 const TypeLong *r1 = t2->is_long();
894
895 if( r0->_hi < r1->_lo ) // Range is always low?
896 return TypeInt::CC_LT;
897 else if( r0->_lo > r1->_hi ) // Range is always high?
898 return TypeInt::CC_GT;
899
900 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
901 assert(r0->get_con() == r1->get_con(), "must be equal");
902 return TypeInt::CC_EQ; // Equal results.
903 } else if( r0->_hi == r1->_lo ) // Range is never high?
904 return TypeInt::CC_LE;
905 else if( r0->_lo == r1->_hi ) // Range is never low?
906 return TypeInt::CC_GE;
907 return TypeInt::CC; // else use worst case results
908 }
909
910
911 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information.
912 // If both inputs are constants, compare them.
913 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const {
914 assert(!t1->isa_ptr(), "obsolete usage of CmpUL");
915
916 // comparing two unsigned longs
917 const TypeLong* r0 = t1->is_long(); // Handy access
918 const TypeLong* r1 = t2->is_long();
919
920 // Current installed version
921 // Compare ranges for non-overlap
922 julong lo0 = r0->_lo;
923 julong hi0 = r0->_hi;
924 julong lo1 = r1->_lo;
925 julong hi1 = r1->_hi;
926
927 // If either one has both negative and positive values,
928 // it therefore contains both 0 and -1, and since [0..-1] is the
929 // full unsigned range, the type must act as an unsigned bottom.
930 bool bot0 = ((jlong)(lo0 ^ hi0) < 0);
931 bool bot1 = ((jlong)(lo1 ^ hi1) < 0);
932
933 if (bot0 || bot1) {
934 // All unsigned values are LE -1 and GE 0.
935 if (lo0 == 0 && hi0 == 0) {
936 return TypeInt::CC_LE; // 0 <= bot
937 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) {
938 return TypeInt::CC_GE; // -1 >= bot
939 } else if (lo1 == 0 && hi1 == 0) {
940 return TypeInt::CC_GE; // bot >= 0
941 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) {
942 return TypeInt::CC_LE; // bot <= -1
943 }
944 } else {
945 // We can use ranges of the form [lo..hi] if signs are the same.
946 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
947 // results are reversed, '-' > '+' for unsigned compare
948 if (hi0 < lo1) {
949 return TypeInt::CC_LT; // smaller
950 } else if (lo0 > hi1) {
951 return TypeInt::CC_GT; // greater
952 } else if (hi0 == lo1 && lo0 == hi1) {
953 return TypeInt::CC_EQ; // Equal results
954 } else if (lo0 >= hi1) {
955 return TypeInt::CC_GE;
956 } else if (hi0 <= lo1) {
957 return TypeInt::CC_LE;
958 }
959 }
960
961 return TypeInt::CC; // else use worst case results
962 }
963
964 //=============================================================================
965 //------------------------------sub--------------------------------------------
966 // Simplify an CmpP (compare 2 pointers) node, based on local information.
967 // If both inputs are constants, compare them.
968 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const {
969 const TypePtr *r0 = t1->is_ptr(); // Handy access
970 const TypePtr *r1 = t2->is_ptr();
971
972 // Undefined inputs makes for an undefined result
973 if( TypePtr::above_centerline(r0->_ptr) ||
974 TypePtr::above_centerline(r1->_ptr) )
975 return Type::TOP;
976
977 if (r0 == r1 && r0->singleton()) {
978 // Equal pointer constants (klasses, nulls, etc.)
979 return TypeInt::CC_EQ;
980 }
981
982 // See if it is 2 unrelated classes.
983 const TypeOopPtr* p0 = r0->isa_oopptr();
984 const TypeOopPtr* p1 = r1->isa_oopptr();
985 const TypeKlassPtr* k0 = r0->isa_klassptr();
986 const TypeKlassPtr* k1 = r1->isa_klassptr();
987 if ((p0 && p1) || (k0 && k1)) {
988 if (p0 && p1) {
989 Node* in1 = in(1)->uncast();
990 Node* in2 = in(2)->uncast();
991 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1, nullptr);
992 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2, nullptr);
993 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, nullptr)) {
994 return TypeInt::CC_GT; // different pointers
995 }
996 }
997 bool xklass0 = p0 ? p0->klass_is_exact() : k0->klass_is_exact();
998 bool xklass1 = p1 ? p1->klass_is_exact() : k1->klass_is_exact();
999 bool unrelated_classes = false;
1000
1001 if ((p0 && p0->is_same_java_type_as(p1)) ||
1002 (k0 && k0->is_same_java_type_as(k1))) {
1003 } else if ((p0 && !p1->maybe_java_subtype_of(p0) && !p0->maybe_java_subtype_of(p1)) ||
1004 (k0 && !k1->maybe_java_subtype_of(k0) && !k0->maybe_java_subtype_of(k1))) {
1005 unrelated_classes = true;
1006 } else if ((p0 && !p1->maybe_java_subtype_of(p0)) ||
1007 (k0 && !k1->maybe_java_subtype_of(k0))) {
1008 unrelated_classes = xklass1;
1009 } else if ((p0 && !p0->maybe_java_subtype_of(p1)) ||
1010 (k0 && !k0->maybe_java_subtype_of(k1))) {
1011 unrelated_classes = xklass0;
1012 }
1013
1014 if (unrelated_classes) {
1015 // The oops classes are known to be unrelated. If the joined PTRs of
1016 // two oops is not Null and not Bottom, then we are sure that one
1017 // of the two oops is non-null, and the comparison will always fail.
1018 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
1019 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
1020 return TypeInt::CC_GT;
1021 }
1022 }
1023 }
1024
1025 // Known constants can be compared exactly
1026 // Null can be distinguished from any NotNull pointers
1027 // Unknown inputs makes an unknown result
1028 if( r0->singleton() ) {
1029 intptr_t bits0 = r0->get_con();
1030 if( r1->singleton() )
1031 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
1032 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1033 } else if( r1->singleton() ) {
1034 intptr_t bits1 = r1->get_con();
1035 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1036 } else
1037 return TypeInt::CC;
1038 }
1039
1040 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) {
1041 // Return the klass node for (indirect load from OopHandle)
1042 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
1043 // or null if not matching.
1044 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1045 n = bs->step_over_gc_barrier(n);
1046
1047 if (n->Opcode() != Op_LoadP) return nullptr;
1048
1049 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1050 if (!tp || tp->instance_klass() != phase->C->env()->Class_klass()) return nullptr;
1051
1052 Node* adr = n->in(MemNode::Address);
1053 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier.
1054 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return nullptr;
1055 adr = adr->in(MemNode::Address);
1056
1057 intptr_t off = 0;
1058 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off);
1059 if (k == nullptr) return nullptr;
1060 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr();
1061 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return nullptr;
1062
1063 // We've found the klass node of a Java mirror load.
1064 return k;
1065 }
1066
1067 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) {
1068 // for ConP(Foo.class) return ConP(Foo.klass)
1069 // otherwise return null
1070 if (!n->is_Con()) return nullptr;
1071
1072 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1073 if (!tp) return nullptr;
1074
1075 ciType* mirror_type = tp->java_mirror_type();
1076 // TypeInstPtr::java_mirror_type() returns non-null for compile-
1077 // time Class constants only.
1078 if (!mirror_type) return nullptr;
1079
1080 // x.getClass() == int.class can never be true (for all primitive types)
1081 // Return a ConP(null) node for this case.
1082 if (mirror_type->is_classless()) {
1083 return phase->makecon(TypePtr::NULL_PTR);
1084 }
1085
1086 // return the ConP(Foo.klass)
1087 assert(mirror_type->is_klass(), "mirror_type should represent a Klass*");
1088 return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass(), Type::trust_interfaces));
1089 }
1090
1091 //------------------------------Ideal------------------------------------------
1092 // Normalize comparisons between Java mirror loads to compare the klass instead.
1093 //
1094 // Also check for the case of comparing an unknown klass loaded from the primary
1095 // super-type array vs a known klass with no subtypes. This amounts to
1096 // checking to see an unknown klass subtypes a known klass with no subtypes;
1097 // this only happens on an exact match. We can shorten this test by 1 load.
1098 Node *CmpPNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1099 // Normalize comparisons between Java mirrors into comparisons of the low-
1100 // level klass, where a dependent load could be shortened.
1101 //
1102 // The new pattern has a nice effect of matching the same pattern used in the
1103 // fast path of instanceof/checkcast/Class.isInstance(), which allows
1104 // redundant exact type check be optimized away by GVN.
1105 // For example, in
1106 // if (x.getClass() == Foo.class) {
1107 // Foo foo = (Foo) x;
1108 // // ... use a ...
1109 // }
1110 // a CmpPNode could be shared between if_acmpne and checkcast
1111 {
1112 Node* k1 = isa_java_mirror_load(phase, in(1));
1113 Node* k2 = isa_java_mirror_load(phase, in(2));
1114 Node* conk2 = isa_const_java_mirror(phase, in(2));
1115
1116 if (k1 && (k2 || conk2)) {
1117 Node* lhs = k1;
1118 Node* rhs = (k2 != nullptr) ? k2 : conk2;
1119 set_req_X(1, lhs, phase);
1120 set_req_X(2, rhs, phase);
1121 return this;
1122 }
1123 }
1124
1125 // Constant pointer on right?
1126 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
1127 if (t2 == nullptr || !t2->klass_is_exact())
1128 return nullptr;
1129 // Get the constant klass we are comparing to.
1130 ciKlass* superklass = t2->exact_klass();
1131
1132 // Now check for LoadKlass on left.
1133 Node* ldk1 = in(1);
1134 if (ldk1->is_DecodeNKlass()) {
1135 ldk1 = ldk1->in(1);
1136 if (ldk1->Opcode() != Op_LoadNKlass )
1137 return nullptr;
1138 } else if (ldk1->Opcode() != Op_LoadKlass )
1139 return nullptr;
1140 // Take apart the address of the LoadKlass:
1141 Node* adr1 = ldk1->in(MemNode::Address);
1142 intptr_t con2 = 0;
1143 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
1144 if (ldk2 == nullptr)
1145 return nullptr;
1146 if (con2 == oopDesc::klass_offset_in_bytes()) {
1147 // We are inspecting an object's concrete class.
1148 // Short-circuit the check if the query is abstract.
1149 if (superklass->is_interface() ||
1150 superklass->is_abstract()) {
1151 // Make it come out always false:
1152 this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
1153 return this;
1154 }
1155 }
1156
1157 // Check for a LoadKlass from primary supertype array.
1158 // Any nested loadklass from loadklass+con must be from the p.s. array.
1159 if (ldk2->is_DecodeNKlass()) {
1160 // Keep ldk2 as DecodeN since it could be used in CmpP below.
1161 if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
1162 return nullptr;
1163 } else if (ldk2->Opcode() != Op_LoadKlass)
1164 return nullptr;
1165
1166 // Verify that we understand the situation
1167 if (con2 != (intptr_t) superklass->super_check_offset())
1168 return nullptr; // Might be element-klass loading from array klass
1169
1170 // If 'superklass' has no subklasses and is not an interface, then we are
1171 // assured that the only input which will pass the type check is
1172 // 'superklass' itself.
1173 //
1174 // We could be more liberal here, and allow the optimization on interfaces
1175 // which have a single implementor. This would require us to increase the
1176 // expressiveness of the add_dependency() mechanism.
1177 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now.
1178
1179 // Object arrays must have their base element have no subtypes
1180 while (superklass->is_obj_array_klass()) {
1181 ciType* elem = superklass->as_obj_array_klass()->element_type();
1182 superklass = elem->as_klass();
1183 }
1184 if (superklass->is_instance_klass()) {
1185 ciInstanceKlass* ik = superklass->as_instance_klass();
1186 if (ik->has_subklass() || ik->is_interface()) return nullptr;
1187 // Add a dependency if there is a chance that a subclass will be added later.
1188 if (!ik->is_final()) {
1189 phase->C->dependencies()->assert_leaf_type(ik);
1190 }
1191 }
1192
1193 // Bypass the dependent load, and compare directly
1194 this->set_req_X(1, ldk2, phase);
1195
1196 return this;
1197 }
1198
1199 //=============================================================================
1200 //------------------------------sub--------------------------------------------
1201 // Simplify an CmpN (compare 2 pointers) node, based on local information.
1202 // If both inputs are constants, compare them.
1203 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
1204 ShouldNotReachHere();
1205 return bottom_type();
1206 }
1207
1208 //------------------------------Ideal------------------------------------------
1209 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1210 return nullptr;
1211 }
1212
1213 //=============================================================================
1214 //------------------------------Value------------------------------------------
1215 // Simplify an CmpF (compare 2 floats ) node, based on local information.
1216 // If both inputs are constants, compare them.
1217 const Type* CmpFNode::Value(PhaseGVN* phase) const {
1218 const Node* in1 = in(1);
1219 const Node* in2 = in(2);
1220 // Either input is TOP ==> the result is TOP
1221 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1222 if( t1 == Type::TOP ) return Type::TOP;
1223 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1224 if( t2 == Type::TOP ) return Type::TOP;
1225
1226 // Not constants? Don't know squat - even if they are the same
1227 // value! If they are NaN's they compare to LT instead of EQ.
1228 const TypeF *tf1 = t1->isa_float_constant();
1229 const TypeF *tf2 = t2->isa_float_constant();
1230 if( !tf1 || !tf2 ) return TypeInt::CC;
1231
1232 // This implements the Java bytecode fcmpl, so unordered returns -1.
1233 if( tf1->is_nan() || tf2->is_nan() )
1234 return TypeInt::CC_LT;
1235
1236 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
1237 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
1238 assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
1239 return TypeInt::CC_EQ;
1240 }
1241
1242
1243 //=============================================================================
1244 //------------------------------Value------------------------------------------
1245 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
1246 // If both inputs are constants, compare them.
1247 const Type* CmpDNode::Value(PhaseGVN* phase) const {
1248 const Node* in1 = in(1);
1249 const Node* in2 = in(2);
1250 // Either input is TOP ==> the result is TOP
1251 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1252 if( t1 == Type::TOP ) return Type::TOP;
1253 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1254 if( t2 == Type::TOP ) return Type::TOP;
1255
1256 // Not constants? Don't know squat - even if they are the same
1257 // value! If they are NaN's they compare to LT instead of EQ.
1258 const TypeD *td1 = t1->isa_double_constant();
1259 const TypeD *td2 = t2->isa_double_constant();
1260 if( !td1 || !td2 ) return TypeInt::CC;
1261
1262 // This implements the Java bytecode dcmpl, so unordered returns -1.
1263 if( td1->is_nan() || td2->is_nan() )
1264 return TypeInt::CC_LT;
1265
1266 if( td1->_d < td2->_d ) return TypeInt::CC_LT;
1267 if( td1->_d > td2->_d ) return TypeInt::CC_GT;
1268 assert( td1->_d == td2->_d, "do not understand FP behavior" );
1269 return TypeInt::CC_EQ;
1270 }
1271
1272 //------------------------------Ideal------------------------------------------
1273 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
1274 // Check if we can change this to a CmpF and remove a ConvD2F operation.
1275 // Change (CMPD (F2D (float)) (ConD value))
1276 // To (CMPF (float) (ConF value))
1277 // Valid when 'value' does not lose precision as a float.
1278 // Benefits: eliminates conversion, does not require 24-bit mode
1279
1280 // NaNs prevent commuting operands. This transform works regardless of the
1281 // order of ConD and ConvF2D inputs by preserving the original order.
1282 int idx_f2d = 1; // ConvF2D on left side?
1283 if( in(idx_f2d)->Opcode() != Op_ConvF2D )
1284 idx_f2d = 2; // No, swap to check for reversed args
1285 int idx_con = 3-idx_f2d; // Check for the constant on other input
1286
1287 if( ConvertCmpD2CmpF &&
1288 in(idx_f2d)->Opcode() == Op_ConvF2D &&
1289 in(idx_con)->Opcode() == Op_ConD ) {
1290 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
1291 double t2_value_as_double = t2->_d;
1292 float t2_value_as_float = (float)t2_value_as_double;
1293 if( t2_value_as_double == (double)t2_value_as_float ) {
1294 // Test value can be represented as a float
1295 // Eliminate the conversion to double and create new comparison
1296 Node *new_in1 = in(idx_f2d)->in(1);
1297 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
1298 if( idx_f2d != 1 ) { // Must flip args to match original order
1299 Node *tmp = new_in1;
1300 new_in1 = new_in2;
1301 new_in2 = tmp;
1302 }
1303 CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
1304 ? new CmpF3Node( new_in1, new_in2 )
1305 : new CmpFNode ( new_in1, new_in2 ) ;
1306 return new_cmp; // Changed to CmpFNode
1307 }
1308 // Testing value required the precision of a double
1309 }
1310 return nullptr; // No change
1311 }
1312
1313
1314 //=============================================================================
1315 //------------------------------cc2logical-------------------------------------
1316 // Convert a condition code type to a logical type
1317 const Type *BoolTest::cc2logical( const Type *CC ) const {
1318 if( CC == Type::TOP ) return Type::TOP;
1319 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
1320 const TypeInt *ti = CC->is_int();
1321 if( ti->is_con() ) { // Only 1 kind of condition codes set?
1322 // Match low order 2 bits
1323 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
1324 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result
1325 return TypeInt::make(tmp); // Boolean result
1326 }
1327
1328 if( CC == TypeInt::CC_GE ) {
1329 if( _test == ge ) return TypeInt::ONE;
1330 if( _test == lt ) return TypeInt::ZERO;
1331 }
1332 if( CC == TypeInt::CC_LE ) {
1333 if( _test == le ) return TypeInt::ONE;
1334 if( _test == gt ) return TypeInt::ZERO;
1335 }
1336
1337 return TypeInt::BOOL;
1338 }
1339
1340 //------------------------------dump_spec-------------------------------------
1341 // Print special per-node info
1342 void BoolTest::dump_on(outputStream *st) const {
1343 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"};
1344 st->print("%s", msg[_test]);
1345 }
1346
1347 // Returns the logical AND of two tests (or 'never' if both tests can never be true).
1348 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'.
1349 BoolTest::mask BoolTest::merge(BoolTest other) const {
1350 const mask res[illegal+1][illegal+1] = {
1351 // eq, gt, of, lt, ne, le, nof, ge, never, illegal
1352 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq
1353 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt
1354 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of
1355 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt
1356 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne
1357 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le
1358 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof
1359 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge
1360 {never, never, never, never, never, never, never, never, never, illegal}, // never
1361 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal
1362 return res[_test][other._test];
1363 }
1364
1365 //=============================================================================
1366 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
1367 uint BoolNode::size_of() const { return sizeof(BoolNode); }
1368
1369 //------------------------------operator==-------------------------------------
1370 bool BoolNode::cmp( const Node &n ) const {
1371 const BoolNode *b = (const BoolNode *)&n; // Cast up
1372 return (_test._test == b->_test._test);
1373 }
1374
1375 //-------------------------------make_predicate--------------------------------
1376 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1377 if (test_value->is_Con()) return test_value;
1378 if (test_value->is_Bool()) return test_value;
1379 if (test_value->is_CMove() &&
1380 test_value->in(CMoveNode::Condition)->is_Bool()) {
1381 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool();
1382 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1383 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1384 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1385 return bol;
1386 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1387 return phase->transform( bol->negate(phase) );
1388 }
1389 // Else fall through. The CMove gets in the way of the test.
1390 // It should be the case that make_predicate(bol->as_int_value()) == bol.
1391 }
1392 Node* cmp = new CmpINode(test_value, phase->intcon(0));
1393 cmp = phase->transform(cmp);
1394 Node* bol = new BoolNode(cmp, BoolTest::ne);
1395 return phase->transform(bol);
1396 }
1397
1398 //--------------------------------as_int_value---------------------------------
1399 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1400 // Inverse to make_predicate. The CMove probably boils down to a Conv2B.
1401 Node* cmov = CMoveNode::make(nullptr, this,
1402 phase->intcon(0), phase->intcon(1),
1403 TypeInt::BOOL);
1404 return phase->transform(cmov);
1405 }
1406
1407 //----------------------------------negate-------------------------------------
1408 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1409 return new BoolNode(in(1), _test.negate());
1410 }
1411
1412 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub
1413 // overflows and we can prove that C is not in the two resulting ranges.
1414 // This optimization is similar to the one performed by CmpUNode::Value().
1415 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op,
1416 int cmp1_op, const TypeInt* cmp2_type) {
1417 // Only optimize eq/ne integer comparison of add/sub
1418 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1419 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) {
1420 // Skip cases were inputs of add/sub are not integers or of bottom type
1421 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int();
1422 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int();
1423 if ((r0 != nullptr) && (r0 != TypeInt::INT) &&
1424 (r1 != nullptr) && (r1 != TypeInt::INT) &&
1425 (cmp2_type != TypeInt::INT)) {
1426 // Compute exact (long) type range of add/sub result
1427 jlong lo_long = r0->_lo;
1428 jlong hi_long = r0->_hi;
1429 if (cmp1_op == Op_AddI) {
1430 lo_long += r1->_lo;
1431 hi_long += r1->_hi;
1432 } else {
1433 lo_long -= r1->_hi;
1434 hi_long -= r1->_lo;
1435 }
1436 // Check for over-/underflow by casting to integer
1437 int lo_int = (int)lo_long;
1438 int hi_int = (int)hi_long;
1439 bool underflow = lo_long != (jlong)lo_int;
1440 bool overflow = hi_long != (jlong)hi_int;
1441 if ((underflow != overflow) && (hi_int < lo_int)) {
1442 // Overflow on one boundary, compute resulting type ranges:
1443 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT]
1444 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
1445 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w);
1446 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w);
1447 // Compare second input of cmp to both type ranges
1448 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type);
1449 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type);
1450 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) {
1451 // The result of the add/sub will never equal cmp2. Replace BoolNode
1452 // by false (0) if it tests for equality and by true (1) otherwise.
1453 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1);
1454 }
1455 }
1456 }
1457 }
1458 return nullptr;
1459 }
1460
1461 static bool is_counted_loop_cmp(Node *cmp) {
1462 Node *n = cmp->in(1)->in(1);
1463 return n != nullptr &&
1464 n->is_Phi() &&
1465 n->in(0) != nullptr &&
1466 n->in(0)->is_CountedLoop() &&
1467 n->in(0)->as_CountedLoop()->phi() == n;
1468 }
1469
1470 //------------------------------Ideal------------------------------------------
1471 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1472 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1473 // This moves the constant to the right. Helps value-numbering.
1474 Node *cmp = in(1);
1475 if( !cmp->is_Sub() ) return nullptr;
1476 int cop = cmp->Opcode();
1477 if( cop == Op_FastLock || cop == Op_FastUnlock ||
1478 cmp->is_SubTypeCheck() || cop == Op_VectorTest ) {
1479 return nullptr;
1480 }
1481 Node *cmp1 = cmp->in(1);
1482 Node *cmp2 = cmp->in(2);
1483 if( !cmp1 ) return nullptr;
1484
1485 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) {
1486 return nullptr;
1487 }
1488
1489 const int cmp1_op = cmp1->Opcode();
1490 const int cmp2_op = cmp2->Opcode();
1491
1492 // Constant on left?
1493 Node *con = cmp1;
1494 // Move constants to the right of compare's to canonicalize.
1495 // Do not muck with Opaque1 nodes, as this indicates a loop
1496 // guard that cannot change shape.
1497 if (con->is_Con() && !cmp2->is_Con() && cmp2_op != Op_OpaqueZeroTripGuard &&
1498 // Because of NaN's, CmpD and CmpF are not commutative
1499 cop != Op_CmpD && cop != Op_CmpF &&
1500 // Protect against swapping inputs to a compare when it is used by a
1501 // counted loop exit, which requires maintaining the loop-limit as in(2)
1502 !is_counted_loop_exit_test() ) {
1503 // Ok, commute the constant to the right of the cmp node.
1504 // Clone the Node, getting a new Node of the same class
1505 cmp = cmp->clone();
1506 // Swap inputs to the clone
1507 cmp->swap_edges(1, 2);
1508 cmp = phase->transform( cmp );
1509 return new BoolNode( cmp, _test.commute() );
1510 }
1511
1512 // Change "bool eq/ne (cmp (cmove (bool tst (cmp2)) 1 0) 0)" into "bool tst/~tst (cmp2)"
1513 if (cop == Op_CmpI &&
1514 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1515 cmp1_op == Op_CMoveI && cmp2->find_int_con(1) == 0) {
1516 // 0 should be on the true branch
1517 if (cmp1->in(CMoveNode::Condition)->is_Bool() &&
1518 cmp1->in(CMoveNode::IfTrue)->find_int_con(1) == 0 &&
1519 cmp1->in(CMoveNode::IfFalse)->find_int_con(0) != 0) {
1520 BoolNode* target = cmp1->in(CMoveNode::Condition)->as_Bool();
1521 return new BoolNode(target->in(1),
1522 (_test._test == BoolTest::eq) ? target->_test._test :
1523 target->_test.negate());
1524 }
1525 }
1526
1527 // Change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1528 if (cop == Op_CmpI &&
1529 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1530 cmp1_op == Op_AndI && cmp2_op == Op_ConI &&
1531 cmp1->in(2)->Opcode() == Op_ConI) {
1532 const TypeInt *t12 = phase->type(cmp2)->isa_int();
1533 const TypeInt *t112 = phase->type(cmp1->in(2))->isa_int();
1534 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1535 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1536 Node *ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1537 return new BoolNode(ncmp, _test.negate());
1538 }
1539 }
1540
1541 // Same for long type: change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1542 if (cop == Op_CmpL &&
1543 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1544 cmp1_op == Op_AndL && cmp2_op == Op_ConL &&
1545 cmp1->in(2)->Opcode() == Op_ConL) {
1546 const TypeLong *t12 = phase->type(cmp2)->isa_long();
1547 const TypeLong *t112 = phase->type(cmp1->in(2))->isa_long();
1548 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1549 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1550 Node *ncmp = phase->transform(new CmpLNode(cmp1, phase->longcon(0)));
1551 return new BoolNode(ncmp, _test.negate());
1552 }
1553 }
1554
1555 // Change "cmp (add X min_jint) (add Y min_jint)" into "cmpu X Y"
1556 // and "cmp (add X min_jint) c" into "cmpu X (c + min_jint)"
1557 if (cop == Op_CmpI &&
1558 cmp1_op == Op_AddI &&
1559 phase->type(cmp1->in(2)) == TypeInt::MIN) {
1560 if (cmp2_op == Op_ConI) {
1561 Node* ncmp2 = phase->intcon(java_add(cmp2->get_int(), min_jint));
1562 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), ncmp2));
1563 return new BoolNode(ncmp, _test._test);
1564 } else if (cmp2_op == Op_AddI &&
1565 phase->type(cmp2->in(2)) == TypeInt::MIN) {
1566 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), cmp2->in(1)));
1567 return new BoolNode(ncmp, _test._test);
1568 }
1569 }
1570
1571 // Change "cmp (add X min_jlong) (add Y min_jlong)" into "cmpu X Y"
1572 // and "cmp (add X min_jlong) c" into "cmpu X (c + min_jlong)"
1573 if (cop == Op_CmpL &&
1574 cmp1_op == Op_AddL &&
1575 phase->type(cmp1->in(2)) == TypeLong::MIN) {
1576 if (cmp2_op == Op_ConL) {
1577 Node* ncmp2 = phase->longcon(java_add(cmp2->get_long(), min_jlong));
1578 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), ncmp2));
1579 return new BoolNode(ncmp, _test._test);
1580 } else if (cmp2_op == Op_AddL &&
1581 phase->type(cmp2->in(2)) == TypeLong::MIN) {
1582 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), cmp2->in(1)));
1583 return new BoolNode(ncmp, _test._test);
1584 }
1585 }
1586
1587 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1588 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the
1589 // test instead.
1590 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1591 if (cmp2_type == nullptr) return nullptr;
1592 Node* j_xor = cmp1;
1593 if( cmp2_type == TypeInt::ZERO &&
1594 cmp1_op == Op_XorI &&
1595 j_xor->in(1) != j_xor && // An xor of itself is dead
1596 phase->type( j_xor->in(1) ) == TypeInt::BOOL &&
1597 phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1598 (_test._test == BoolTest::eq ||
1599 _test._test == BoolTest::ne) ) {
1600 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2));
1601 return new BoolNode( ncmp, _test.negate() );
1602 }
1603
1604 // Change ((x & m) u<= m) or ((m & x) u<= m) to always true
1605 // Same with ((x & m) u< m+1) and ((m & x) u< m+1)
1606 if (cop == Op_CmpU &&
1607 cmp1_op == Op_AndI) {
1608 Node* bound = nullptr;
1609 if (_test._test == BoolTest::le) {
1610 bound = cmp2;
1611 } else if (_test._test == BoolTest::lt &&
1612 cmp2->Opcode() == Op_AddI &&
1613 cmp2->in(2)->find_int_con(0) == 1) {
1614 bound = cmp2->in(1);
1615 }
1616 if (cmp1->in(2) == bound || cmp1->in(1) == bound) {
1617 return ConINode::make(1);
1618 }
1619 }
1620
1621 // Change ((x & (m - 1)) u< m) into (m > 0)
1622 // This is the off-by-one variant of the above
1623 if (cop == Op_CmpU &&
1624 _test._test == BoolTest::lt &&
1625 cmp1_op == Op_AndI) {
1626 Node* l = cmp1->in(1);
1627 Node* r = cmp1->in(2);
1628 for (int repeat = 0; repeat < 2; repeat++) {
1629 bool match = r->Opcode() == Op_AddI && r->in(2)->find_int_con(0) == -1 &&
1630 r->in(1) == cmp2;
1631 if (match) {
1632 // arraylength known to be non-negative, so a (arraylength != 0) is sufficient,
1633 // but to be compatible with the array range check pattern, use (arraylength u> 0)
1634 Node* ncmp = cmp2->Opcode() == Op_LoadRange
1635 ? phase->transform(new CmpUNode(cmp2, phase->intcon(0)))
1636 : phase->transform(new CmpINode(cmp2, phase->intcon(0)));
1637 return new BoolNode(ncmp, BoolTest::gt);
1638 } else {
1639 // commute and try again
1640 l = cmp1->in(2);
1641 r = cmp1->in(1);
1642 }
1643 }
1644 }
1645
1646 // Change x u< 1 or x u<= 0 to x == 0
1647 // and x u> 0 or u>= 1 to x != 0
1648 if (cop == Op_CmpU &&
1649 cmp1_op != Op_LoadRange &&
1650 (((_test._test == BoolTest::lt || _test._test == BoolTest::ge) &&
1651 cmp2->find_int_con(-1) == 1) ||
1652 ((_test._test == BoolTest::le || _test._test == BoolTest::gt) &&
1653 cmp2->find_int_con(-1) == 0))) {
1654 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1655 return new BoolNode(ncmp, _test.is_less() ? BoolTest::eq : BoolTest::ne);
1656 }
1657
1658 // Change (arraylength <= 0) or (arraylength == 0)
1659 // into (arraylength u<= 0)
1660 // Also change (arraylength != 0) into (arraylength u> 0)
1661 // The latter version matches the code pattern generated for
1662 // array range checks, which will more likely be optimized later.
1663 if (cop == Op_CmpI &&
1664 cmp1_op == Op_LoadRange &&
1665 cmp2->find_int_con(-1) == 0) {
1666 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) {
1667 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1668 return new BoolNode(ncmp, BoolTest::le);
1669 } else if (_test._test == BoolTest::ne) {
1670 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1671 return new BoolNode(ncmp, BoolTest::gt);
1672 }
1673 }
1674
1675 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1676 // This is a standard idiom for branching on a boolean value.
1677 Node *c2b = cmp1;
1678 if( cmp2_type == TypeInt::ZERO &&
1679 cmp1_op == Op_Conv2B &&
1680 (_test._test == BoolTest::eq ||
1681 _test._test == BoolTest::ne) ) {
1682 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1683 ? (Node*)new CmpINode(c2b->in(1),cmp2)
1684 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1685 );
1686 return new BoolNode( ncmp, _test._test );
1687 }
1688
1689 // Comparing a SubI against a zero is equal to comparing the SubI
1690 // arguments directly. This only works for eq and ne comparisons
1691 // due to possible integer overflow.
1692 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1693 (cop == Op_CmpI) &&
1694 (cmp1_op == Op_SubI) &&
1695 ( cmp2_type == TypeInt::ZERO ) ) {
1696 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2)));
1697 return new BoolNode( ncmp, _test._test );
1698 }
1699
1700 // Same as above but with and AddI of a constant
1701 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1702 cop == Op_CmpI &&
1703 cmp1_op == Op_AddI &&
1704 cmp1->in(2) != nullptr &&
1705 phase->type(cmp1->in(2))->isa_int() &&
1706 phase->type(cmp1->in(2))->is_int()->is_con() &&
1707 cmp2_type == TypeInt::ZERO &&
1708 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape
1709 ) {
1710 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int();
1711 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi)));
1712 return new BoolNode( ncmp, _test._test );
1713 }
1714
1715 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)"
1716 // since zero check of conditional negation of an integer is equal to
1717 // zero check of the integer directly.
1718 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1719 (cop == Op_CmpI) &&
1720 (cmp2_type == TypeInt::ZERO) &&
1721 (cmp1_op == Op_Phi)) {
1722 // There should be a diamond phi with true path at index 1 or 2
1723 PhiNode *phi = cmp1->as_Phi();
1724 int idx_true = phi->is_diamond_phi();
1725 if (idx_true != 0) {
1726 // True input is in(idx_true) while false input is in(3 - idx_true)
1727 Node *tin = phi->in(idx_true);
1728 Node *fin = phi->in(3 - idx_true);
1729 if ((tin->Opcode() == Op_SubI) &&
1730 (phase->type(tin->in(1)) == TypeInt::ZERO) &&
1731 (tin->in(2) == fin)) {
1732 // Found conditional negation at true path, create a new CmpINode without that
1733 Node *ncmp = phase->transform(new CmpINode(fin, cmp2));
1734 return new BoolNode(ncmp, _test._test);
1735 }
1736 if ((fin->Opcode() == Op_SubI) &&
1737 (phase->type(fin->in(1)) == TypeInt::ZERO) &&
1738 (fin->in(2) == tin)) {
1739 // Found conditional negation at false path, create a new CmpINode without that
1740 Node *ncmp = phase->transform(new CmpINode(tin, cmp2));
1741 return new BoolNode(ncmp, _test._test);
1742 }
1743 }
1744 }
1745
1746 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the
1747 // most general case because negating 0x80000000 does nothing. Needed for
1748 // the CmpF3/SubI/CmpI idiom.
1749 if( cop == Op_CmpI &&
1750 cmp1_op == Op_SubI &&
1751 cmp2_type == TypeInt::ZERO &&
1752 phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1753 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1754 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2));
1755 return new BoolNode( ncmp, _test.commute() );
1756 }
1757
1758 // Try to optimize signed integer comparison
1759 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type);
1760
1761 // The transformation below is not valid for either signed or unsigned
1762 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1763 // This transformation can be resurrected when we are able to
1764 // make inferences about the range of values being subtracted from
1765 // (or added to) relative to the wraparound point.
1766 //
1767 // // Remove +/-1's if possible.
1768 // // "X <= Y-1" becomes "X < Y"
1769 // // "X+1 <= Y" becomes "X < Y"
1770 // // "X < Y+1" becomes "X <= Y"
1771 // // "X-1 < Y" becomes "X <= Y"
1772 // // Do not this to compares off of the counted-loop-end. These guys are
1773 // // checking the trip counter and they want to use the post-incremented
1774 // // counter. If they use the PRE-incremented counter, then the counter has
1775 // // to be incremented in a private block on a loop backedge.
1776 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1777 // return nullptr;
1778 // #ifndef PRODUCT
1779 // // Do not do this in a wash GVN pass during verification.
1780 // // Gets triggered by too many simple optimizations to be bothered with
1781 // // re-trying it again and again.
1782 // if( !phase->allow_progress() ) return nullptr;
1783 // #endif
1784 // // Not valid for unsigned compare because of corner cases in involving zero.
1785 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1786 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1787 // // "0 <=u Y" is always true).
1788 // if( cmp->Opcode() == Op_CmpU ) return nullptr;
1789 // int cmp2_op = cmp2->Opcode();
1790 // if( _test._test == BoolTest::le ) {
1791 // if( cmp1_op == Op_AddI &&
1792 // phase->type( cmp1->in(2) ) == TypeInt::ONE )
1793 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1794 // else if( cmp2_op == Op_AddI &&
1795 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1796 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1797 // } else if( _test._test == BoolTest::lt ) {
1798 // if( cmp1_op == Op_AddI &&
1799 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1800 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1801 // else if( cmp2_op == Op_AddI &&
1802 // phase->type( cmp2->in(2) ) == TypeInt::ONE )
1803 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1804 // }
1805 }
1806
1807 //------------------------------Value------------------------------------------
1808 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
1809 // based on local information. If the input is constant, do it.
1810 const Type* BoolNode::Value(PhaseGVN* phase) const {
1811 return _test.cc2logical( phase->type( in(1) ) );
1812 }
1813
1814 #ifndef PRODUCT
1815 //------------------------------dump_spec--------------------------------------
1816 // Dump special per-node info
1817 void BoolNode::dump_spec(outputStream *st) const {
1818 st->print("[");
1819 _test.dump_on(st);
1820 st->print("]");
1821 }
1822 #endif
1823
1824 //----------------------is_counted_loop_exit_test------------------------------
1825 // Returns true if node is used by a counted loop node.
1826 bool BoolNode::is_counted_loop_exit_test() {
1827 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
1828 Node* use = fast_out(i);
1829 if (use->is_CountedLoopEnd()) {
1830 return true;
1831 }
1832 }
1833 return false;
1834 }
1835
1836 //=============================================================================
1837 //------------------------------Value------------------------------------------
1838 const Type* AbsNode::Value(PhaseGVN* phase) const {
1839 const Type* t1 = phase->type(in(1));
1840 if (t1 == Type::TOP) return Type::TOP;
1841
1842 switch (t1->base()) {
1843 case Type::Int: {
1844 const TypeInt* ti = t1->is_int();
1845 if (ti->is_con()) {
1846 return TypeInt::make(uabs(ti->get_con()));
1847 }
1848 break;
1849 }
1850 case Type::Long: {
1851 const TypeLong* tl = t1->is_long();
1852 if (tl->is_con()) {
1853 return TypeLong::make(uabs(tl->get_con()));
1854 }
1855 break;
1856 }
1857 case Type::FloatCon:
1858 return TypeF::make(abs(t1->getf()));
1859 case Type::DoubleCon:
1860 return TypeD::make(abs(t1->getd()));
1861 default:
1862 break;
1863 }
1864
1865 return bottom_type();
1866 }
1867
1868 //------------------------------Identity----------------------------------------
1869 Node* AbsNode::Identity(PhaseGVN* phase) {
1870 Node* in1 = in(1);
1871 // No need to do abs for non-negative values
1872 if (phase->type(in1)->higher_equal(TypeInt::POS) ||
1873 phase->type(in1)->higher_equal(TypeLong::POS)) {
1874 return in1;
1875 }
1876 // Convert "abs(abs(x))" into "abs(x)"
1877 if (in1->Opcode() == Opcode()) {
1878 return in1;
1879 }
1880 return this;
1881 }
1882
1883 //------------------------------Ideal------------------------------------------
1884 Node* AbsNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1885 Node* in1 = in(1);
1886 // Convert "abs(0-x)" into "abs(x)"
1887 if (in1->is_Sub() && phase->type(in1->in(1))->is_zero_type()) {
1888 set_req_X(1, in1->in(2), phase);
1889 return this;
1890 }
1891 return nullptr;
1892 }
1893
1894 //=============================================================================
1895 //------------------------------Value------------------------------------------
1896 // Compute sqrt
1897 const Type* SqrtDNode::Value(PhaseGVN* phase) const {
1898 const Type *t1 = phase->type( in(1) );
1899 if( t1 == Type::TOP ) return Type::TOP;
1900 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1901 double d = t1->getd();
1902 if( d < 0.0 ) return Type::DOUBLE;
1903 return TypeD::make( sqrt( d ) );
1904 }
1905
1906 const Type* SqrtFNode::Value(PhaseGVN* phase) const {
1907 const Type *t1 = phase->type( in(1) );
1908 if( t1 == Type::TOP ) return Type::TOP;
1909 if( t1->base() != Type::FloatCon ) return Type::FLOAT;
1910 float f = t1->getf();
1911 if( f < 0.0f ) return Type::FLOAT;
1912 return TypeF::make( (float)sqrt( (double)f ) );
1913 }
1914
1915 const Type* ReverseINode::Value(PhaseGVN* phase) const {
1916 const Type *t1 = phase->type( in(1) );
1917 if (t1 == Type::TOP) {
1918 return Type::TOP;
1919 }
1920 const TypeInt* t1int = t1->isa_int();
1921 if (t1int && t1int->is_con()) {
1922 jint res = reverse_bits(t1int->get_con());
1923 return TypeInt::make(res);
1924 }
1925 return bottom_type();
1926 }
1927
1928 const Type* ReverseLNode::Value(PhaseGVN* phase) const {
1929 const Type *t1 = phase->type( in(1) );
1930 if (t1 == Type::TOP) {
1931 return Type::TOP;
1932 }
1933 const TypeLong* t1long = t1->isa_long();
1934 if (t1long && t1long->is_con()) {
1935 jlong res = reverse_bits(t1long->get_con());
1936 return TypeLong::make(res);
1937 }
1938 return bottom_type();
1939 }
1940
1941 Node* ReverseINode::Identity(PhaseGVN* phase) {
1942 if (in(1)->Opcode() == Op_ReverseI) {
1943 return in(1)->in(1);
1944 }
1945 return this;
1946 }
1947
1948 Node* ReverseLNode::Identity(PhaseGVN* phase) {
1949 if (in(1)->Opcode() == Op_ReverseL) {
1950 return in(1)->in(1);
1951 }
1952 return this;
1953 }