1 /*
2 * Copyright (c) 1997, 2022, 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/inlinetypenode.hpp"
34 #include "opto/loopnode.hpp"
35 #include "opto/matcher.hpp"
36 #include "opto/movenode.hpp"
37 #include "opto/mulnode.hpp"
38 #include "opto/opcodes.hpp"
39 #include "opto/phaseX.hpp"
40 #include "opto/subnode.hpp"
41 #include "runtime/sharedRuntime.hpp"
42 #include "utilities/moveBits.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 // Also catch: "(X + Opaque2(Y)) - Y". In this case, 'Y' is a loop-varying
75 // trip counter and X is likely to be loop-invariant (that's how O2 Nodes
76 // are originally used, although the optimizer sometimes jiggers things).
77 // This folding through an O2 removes a loop-exit use of a loop-varying
78 // value and generally lowers register pressure in and around the loop.
79 if (in(1)->in(2)->Opcode() == Op_Opaque2 && in(1)->in(2)->in(1) == in(2)) {
80 return in(1)->in(1);
81 }
82 }
83
84 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this;
85 }
86
87 //------------------------------Value------------------------------------------
88 // A subtract node differences it's two inputs.
89 const Type* SubNode::Value_common(PhaseTransform *phase) const {
90 const Node* in1 = in(1);
91 const Node* in2 = in(2);
92 // Either input is TOP ==> the result is TOP
93 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
94 if( t1 == Type::TOP ) return Type::TOP;
95 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
96 if( t2 == Type::TOP ) return Type::TOP;
97
98 // Not correct for SubFnode and AddFNode (must check for infinity)
99 // Equal? Subtract is zero
100 if (in1->eqv_uncast(in2)) return add_id();
101
102 // Either input is BOTTOM ==> the result is the local BOTTOM
103 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM )
104 return bottom_type();
105
106 return NULL;
107 }
108
109 const Type* SubNode::Value(PhaseGVN* phase) const {
110 const Type* t = Value_common(phase);
111 if (t != NULL) {
112 return t;
113 }
114 const Type* t1 = phase->type(in(1));
115 const Type* t2 = phase->type(in(2));
116 return sub(t1,t2); // Local flavor of type subtraction
117
118 }
119
120 SubNode* SubNode::make(Node* in1, Node* in2, BasicType bt) {
121 switch (bt) {
122 case T_INT:
123 return new SubINode(in1, in2);
124 case T_LONG:
125 return new SubLNode(in1, in2);
126 default:
127 fatal("Not implemented for %s", type2name(bt));
128 }
129 return NULL;
130 }
131
132 //=============================================================================
133 //------------------------------Helper function--------------------------------
134
135 static bool is_cloop_increment(Node* inc) {
136 precond(inc->Opcode() == Op_AddI || inc->Opcode() == Op_AddL);
137
138 if (!inc->in(1)->is_Phi()) {
139 return false;
140 }
141 const PhiNode* phi = inc->in(1)->as_Phi();
142
143 if (!phi->region()->is_CountedLoop()) {
144 return false;
145 }
146
147 return inc == phi->region()->as_CountedLoop()->incr();
148 }
149
150 // Given the expression '(x + C) - v', or
151 // 'v - (x + C)', we examine nodes '+' and 'v':
152 //
153 // 1. Do not convert if '+' is a counted-loop increment, because the '-' is
154 // loop invariant and converting extends the live-range of 'x' to overlap
155 // with the '+', forcing another register to be used in the loop.
156 //
157 // 2. Do not convert if 'v' is a counted-loop induction variable, because
158 // 'x' might be invariant.
159 //
160 static bool ok_to_convert(Node* inc, Node* var) {
161 return !(is_cloop_increment(inc) || var->is_cloop_ind_var());
162 }
163
164 //------------------------------Ideal------------------------------------------
165 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){
166 Node *in1 = in(1);
167 Node *in2 = in(2);
168 uint op1 = in1->Opcode();
169 uint op2 = in2->Opcode();
170
171 #ifdef ASSERT
172 // Check for dead loop
173 if ((in1 == this) || (in2 == this) ||
174 ((op1 == Op_AddI || op1 == Op_SubI) &&
175 ((in1->in(1) == this) || (in1->in(2) == this) ||
176 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
177 assert(false, "dead loop in SubINode::Ideal");
178 }
179 #endif
180
181 const Type *t2 = phase->type( in2 );
182 if( t2 == Type::TOP ) return NULL;
183 // Convert "x-c0" into "x+ -c0".
184 if( t2->base() == Type::Int ){ // Might be bottom or top...
185 const TypeInt *i = t2->is_int();
186 if( i->is_con() )
187 return new AddINode(in1, phase->intcon(-i->get_con()));
188 }
189
190 // Convert "(x+c0) - y" into (x-y) + c0"
191 // Do not collapse (x+c0)-y if "+" is a loop increment or
192 // if "y" is a loop induction variable.
193 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) {
194 const Type *tadd = phase->type( in1->in(2) );
195 if( tadd->singleton() && tadd != Type::TOP ) {
196 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 ));
197 return new AddINode( sub2, in1->in(2) );
198 }
199 }
200
201 // Convert "x - (y+c0)" into "(x-y) - c0" AND
202 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
203 // Need the same check as in above optimization but reversed.
204 if (op2 == Op_AddI
205 && ok_to_convert(in2, in1)
206 && in2->in(2)->Opcode() == Op_ConI) {
207 jint c0 = phase->type(in2->in(2))->isa_int()->get_con();
208 Node* in21 = in2->in(1);
209 if (in1->Opcode() == Op_ConI) {
210 // Match c1
211 jint c1 = phase->type(in1)->isa_int()->get_con();
212 Node* sub2 = phase->intcon(java_subtract(c1, c0));
213 return new SubINode(sub2, in21);
214 } else {
215 // Match x
216 Node* sub2 = phase->transform(new SubINode(in1, in21));
217 Node* neg_c0 = phase->intcon(-c0);
218 return new AddINode(sub2, neg_c0);
219 }
220 }
221
222 const Type *t1 = phase->type( in1 );
223 if( t1 == Type::TOP ) return NULL;
224
225 #ifdef ASSERT
226 // Check for dead loop
227 if ((op2 == Op_AddI || op2 == Op_SubI) &&
228 ((in2->in(1) == this) || (in2->in(2) == this) ||
229 (in2->in(1) == in2) || (in2->in(2) == in2))) {
230 assert(false, "dead loop in SubINode::Ideal");
231 }
232 #endif
233
234 // Convert "x - (x+y)" into "-y"
235 if (op2 == Op_AddI && in1 == in2->in(1)) {
236 return new SubINode(phase->intcon(0), in2->in(2));
237 }
238 // Convert "(x-y) - x" into "-y"
239 if (op1 == Op_SubI && in1->in(1) == in2) {
240 return new SubINode(phase->intcon(0), in1->in(2));
241 }
242 // Convert "x - (y+x)" into "-y"
243 if (op2 == Op_AddI && in1 == in2->in(2)) {
244 return new SubINode(phase->intcon(0), in2->in(1));
245 }
246
247 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity().
248 if (t1 == TypeInt::ZERO && op2 == Op_SubI && phase->type(in2->in(1)) != TypeInt::ZERO) {
249 return new SubINode(in2->in(2), in2->in(1));
250 }
251
252 // Convert "0 - (x+con)" into "-con-x"
253 jint con;
254 if( t1 == TypeInt::ZERO && op2 == Op_AddI &&
255 (con = in2->in(2)->find_int_con(0)) != 0 )
256 return new SubINode( phase->intcon(-con), in2->in(1) );
257
258 // Convert "(X+A) - (X+B)" into "A - B"
259 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) )
260 return new SubINode( in1->in(2), in2->in(2) );
261
262 // Convert "(A+X) - (B+X)" into "A - B"
263 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) )
264 return new SubINode( in1->in(1), in2->in(1) );
265
266 // Convert "(A+X) - (X+B)" into "A - B"
267 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) )
268 return new SubINode( in1->in(1), in2->in(2) );
269
270 // Convert "(X+A) - (B+X)" into "A - B"
271 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) )
272 return new SubINode( in1->in(2), in2->in(1) );
273
274 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally
275 // nicer to optimize than subtract.
276 if( op2 == Op_SubI && in2->outcnt() == 1) {
277 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) );
278 return new SubINode( add1, in2->in(1) );
279 }
280
281 // Associative
282 if (op1 == Op_MulI && op2 == Op_MulI) {
283 Node* sub_in1 = NULL;
284 Node* sub_in2 = NULL;
285 Node* mul_in = NULL;
286
287 if (in1->in(1) == in2->in(1)) {
288 // Convert "a*b-a*c into a*(b-c)
289 sub_in1 = in1->in(2);
290 sub_in2 = in2->in(2);
291 mul_in = in1->in(1);
292 } else if (in1->in(2) == in2->in(1)) {
293 // Convert a*b-b*c into b*(a-c)
294 sub_in1 = in1->in(1);
295 sub_in2 = in2->in(2);
296 mul_in = in1->in(2);
297 } else if (in1->in(2) == in2->in(2)) {
298 // Convert a*c-b*c into (a-b)*c
299 sub_in1 = in1->in(1);
300 sub_in2 = in2->in(1);
301 mul_in = in1->in(2);
302 } else if (in1->in(1) == in2->in(2)) {
303 // Convert a*b-c*a into a*(b-c)
304 sub_in1 = in1->in(2);
305 sub_in2 = in2->in(1);
306 mul_in = in1->in(1);
307 }
308
309 if (mul_in != NULL) {
310 Node* sub = phase->transform(new SubINode(sub_in1, sub_in2));
311 return new MulINode(mul_in, sub);
312 }
313 }
314
315 // Convert "0-(A>>31)" into "(A>>>31)"
316 if ( op2 == Op_RShiftI ) {
317 Node *in21 = in2->in(1);
318 Node *in22 = in2->in(2);
319 const TypeInt *zero = phase->type(in1)->isa_int();
320 const TypeInt *t21 = phase->type(in21)->isa_int();
321 const TypeInt *t22 = phase->type(in22)->isa_int();
322 if ( t21 && t22 && zero == TypeInt::ZERO && t22->is_con(31) ) {
323 return new URShiftINode(in21, in22);
324 }
325 }
326
327 return NULL;
328 }
329
330 //------------------------------sub--------------------------------------------
331 // A subtract node differences it's two inputs.
332 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const {
333 const TypeInt *r0 = t1->is_int(); // Handy access
334 const TypeInt *r1 = t2->is_int();
335 int32_t lo = java_subtract(r0->_lo, r1->_hi);
336 int32_t hi = java_subtract(r0->_hi, r1->_lo);
337
338 // We next check for 32-bit overflow.
339 // If that happens, we just assume all integers are possible.
340 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
341 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
342 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
343 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
344 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen));
345 else // Overflow; assume all integers
346 return TypeInt::INT;
347 }
348
349 //=============================================================================
350 //------------------------------Ideal------------------------------------------
351 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
352 Node *in1 = in(1);
353 Node *in2 = in(2);
354 uint op1 = in1->Opcode();
355 uint op2 = in2->Opcode();
356
357 #ifdef ASSERT
358 // Check for dead loop
359 if ((in1 == this) || (in2 == this) ||
360 ((op1 == Op_AddL || op1 == Op_SubL) &&
361 ((in1->in(1) == this) || (in1->in(2) == this) ||
362 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
363 assert(false, "dead loop in SubLNode::Ideal");
364 }
365 #endif
366
367 if( phase->type( in2 ) == Type::TOP ) return NULL;
368 const TypeLong *i = phase->type( in2 )->isa_long();
369 // Convert "x-c0" into "x+ -c0".
370 if( i && // Might be bottom or top...
371 i->is_con() )
372 return new AddLNode(in1, phase->longcon(-i->get_con()));
373
374 // Convert "(x+c0) - y" into (x-y) + c0"
375 // Do not collapse (x+c0)-y if "+" is a loop increment or
376 // if "y" is a loop induction variable.
377 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) {
378 Node *in11 = in1->in(1);
379 const Type *tadd = phase->type( in1->in(2) );
380 if( tadd->singleton() && tadd != Type::TOP ) {
381 Node *sub2 = phase->transform( new SubLNode( in11, in2 ));
382 return new AddLNode( sub2, in1->in(2) );
383 }
384 }
385
386 // Convert "x - (y+c0)" into "(x-y) - c0" AND
387 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
388 // Need the same check as in above optimization but reversed.
389 if (op2 == Op_AddL
390 && ok_to_convert(in2, in1)
391 && in2->in(2)->Opcode() == Op_ConL) {
392 jlong c0 = phase->type(in2->in(2))->isa_long()->get_con();
393 Node* in21 = in2->in(1);
394 if (in1->Opcode() == Op_ConL) {
395 // Match c1
396 jlong c1 = phase->type(in1)->isa_long()->get_con();
397 Node* sub2 = phase->longcon(java_subtract(c1, c0));
398 return new SubLNode(sub2, in21);
399 } else {
400 Node* sub2 = phase->transform(new SubLNode(in1, in21));
401 Node* neg_c0 = phase->longcon(-c0);
402 return new AddLNode(sub2, neg_c0);
403 }
404 }
405
406 const Type *t1 = phase->type( in1 );
407 if( t1 == Type::TOP ) return NULL;
408
409 #ifdef ASSERT
410 // Check for dead loop
411 if ((op2 == Op_AddL || op2 == Op_SubL) &&
412 ((in2->in(1) == this) || (in2->in(2) == this) ||
413 (in2->in(1) == in2) || (in2->in(2) == in2))) {
414 assert(false, "dead loop in SubLNode::Ideal");
415 }
416 #endif
417
418 // Convert "x - (x+y)" into "-y"
419 if (op2 == Op_AddL && in1 == in2->in(1)) {
420 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(2));
421 }
422 // Convert "(x-y) - x" into "-y"
423 if (op1 == Op_SubL && in1->in(1) == in2) {
424 return new SubLNode(phase->makecon(TypeLong::ZERO), in1->in(2));
425 }
426 // Convert "x - (y+x)" into "-y"
427 if (op2 == Op_AddL && in1 == in2->in(2)) {
428 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(1));
429 }
430
431 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity.
432 if (t1 == TypeLong::ZERO && op2 == Op_SubL && phase->type(in2->in(1)) != TypeLong::ZERO) {
433 return new SubLNode(in2->in(2), in2->in(1));
434 }
435
436 // Convert "(X+A) - (X+B)" into "A - B"
437 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) )
438 return new SubLNode( in1->in(2), in2->in(2) );
439
440 // Convert "(A+X) - (B+X)" into "A - B"
441 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) )
442 return new SubLNode( in1->in(1), in2->in(1) );
443
444 // Convert "(A+X) - (X+B)" into "A - B"
445 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(1) )
446 return new SubLNode( in1->in(1), in2->in(2) );
447
448 // Convert "(X+A) - (B+X)" into "A - B"
449 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(2) )
450 return new SubLNode( in1->in(2), in2->in(1) );
451
452 // Convert "A-(B-C)" into (A+C)-B"
453 if( op2 == Op_SubL && in2->outcnt() == 1) {
454 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) );
455 return new SubLNode( add1, in2->in(1) );
456 }
457
458 // Associative
459 if (op1 == Op_MulL && op2 == Op_MulL) {
460 Node* sub_in1 = NULL;
461 Node* sub_in2 = NULL;
462 Node* mul_in = NULL;
463
464 if (in1->in(1) == in2->in(1)) {
465 // Convert "a*b-a*c into a*(b+c)
466 sub_in1 = in1->in(2);
467 sub_in2 = in2->in(2);
468 mul_in = in1->in(1);
469 } else if (in1->in(2) == in2->in(1)) {
470 // Convert a*b-b*c into b*(a-c)
471 sub_in1 = in1->in(1);
472 sub_in2 = in2->in(2);
473 mul_in = in1->in(2);
474 } else if (in1->in(2) == in2->in(2)) {
475 // Convert a*c-b*c into (a-b)*c
476 sub_in1 = in1->in(1);
477 sub_in2 = in2->in(1);
478 mul_in = in1->in(2);
479 } else if (in1->in(1) == in2->in(2)) {
480 // Convert a*b-c*a into a*(b-c)
481 sub_in1 = in1->in(2);
482 sub_in2 = in2->in(1);
483 mul_in = in1->in(1);
484 }
485
486 if (mul_in != NULL) {
487 Node* sub = phase->transform(new SubLNode(sub_in1, sub_in2));
488 return new MulLNode(mul_in, sub);
489 }
490 }
491
492 // Convert "0L-(A>>63)" into "(A>>>63)"
493 if ( op2 == Op_RShiftL ) {
494 Node *in21 = in2->in(1);
495 Node *in22 = in2->in(2);
496 const TypeLong *zero = phase->type(in1)->isa_long();
497 const TypeLong *t21 = phase->type(in21)->isa_long();
498 const TypeInt *t22 = phase->type(in22)->isa_int();
499 if ( t21 && t22 && zero == TypeLong::ZERO && t22->is_con(63) ) {
500 return new URShiftLNode(in21, in22);
501 }
502 }
503
504 return NULL;
505 }
506
507 //------------------------------sub--------------------------------------------
508 // A subtract node differences it's two inputs.
509 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const {
510 const TypeLong *r0 = t1->is_long(); // Handy access
511 const TypeLong *r1 = t2->is_long();
512 jlong lo = java_subtract(r0->_lo, r1->_hi);
513 jlong hi = java_subtract(r0->_hi, r1->_lo);
514
515 // We next check for 32-bit overflow.
516 // If that happens, we just assume all integers are possible.
517 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
518 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
519 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
520 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
521 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen));
522 else // Overflow; assume all integers
523 return TypeLong::LONG;
524 }
525
526 //=============================================================================
527 //------------------------------Value------------------------------------------
528 // A subtract node differences its two inputs.
529 const Type* SubFPNode::Value(PhaseGVN* phase) const {
530 const Node* in1 = in(1);
531 const Node* in2 = in(2);
532 // Either input is TOP ==> the result is TOP
533 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
534 if( t1 == Type::TOP ) return Type::TOP;
535 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
536 if( t2 == Type::TOP ) return Type::TOP;
537
538 // if both operands are infinity of same sign, the result is NaN; do
539 // not replace with zero
540 if (t1->is_finite() && t2->is_finite() && in1 == in2) {
541 return add_id();
542 }
543
544 // Either input is BOTTOM ==> the result is the local BOTTOM
545 const Type *bot = bottom_type();
546 if( (t1 == bot) || (t2 == bot) ||
547 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
548 return bot;
549
550 return sub(t1,t2); // Local flavor of type subtraction
551 }
552
553
554 //=============================================================================
555 //------------------------------Ideal------------------------------------------
556 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
557 const Type *t2 = phase->type( in(2) );
558 // Convert "x-c0" into "x+ -c0".
559 if( t2->base() == Type::FloatCon ) { // Might be bottom or top...
560 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) );
561 }
562
563 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes
564 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0.
565 //if( phase->type(in(1)) == TypeF::ZERO )
566 //return new (phase->C, 2) NegFNode(in(2));
567
568 return NULL;
569 }
570
571 //------------------------------sub--------------------------------------------
572 // A subtract node differences its two inputs.
573 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const {
574 // no folding if one of operands is infinity or NaN, do not do constant folding
575 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) {
576 return TypeF::make( t1->getf() - t2->getf() );
577 }
578 else if( g_isnan(t1->getf()) ) {
579 return t1;
580 }
581 else if( g_isnan(t2->getf()) ) {
582 return t2;
583 }
584 else {
585 return Type::FLOAT;
586 }
587 }
588
589 //=============================================================================
590 //------------------------------Ideal------------------------------------------
591 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){
592 const Type *t2 = phase->type( in(2) );
593 // Convert "x-c0" into "x+ -c0".
594 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top...
595 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) );
596 }
597
598 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes
599 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0.
600 //if( phase->type(in(1)) == TypeD::ZERO )
601 //return new (phase->C, 2) NegDNode(in(2));
602
603 return NULL;
604 }
605
606 //------------------------------sub--------------------------------------------
607 // A subtract node differences its two inputs.
608 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const {
609 // no folding if one of operands is infinity or NaN, do not do constant folding
610 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) {
611 return TypeD::make( t1->getd() - t2->getd() );
612 }
613 else if( g_isnan(t1->getd()) ) {
614 return t1;
615 }
616 else if( g_isnan(t2->getd()) ) {
617 return t2;
618 }
619 else {
620 return Type::DOUBLE;
621 }
622 }
623
624 //=============================================================================
625 //------------------------------Idealize---------------------------------------
626 // Unlike SubNodes, compare must still flatten return value to the
627 // range -1, 0, 1.
628 // And optimizations like those for (X + Y) - X fail if overflow happens.
629 Node* CmpNode::Identity(PhaseGVN* phase) {
630 return this;
631 }
632
633 CmpNode *CmpNode::make(Node *in1, Node *in2, BasicType bt, bool unsigned_comp) {
634 switch (bt) {
635 case T_INT:
636 if (unsigned_comp) {
637 return new CmpUNode(in1, in2);
638 }
639 return new CmpINode(in1, in2);
640 case T_LONG:
641 if (unsigned_comp) {
642 return new CmpULNode(in1, in2);
643 }
644 return new CmpLNode(in1, in2);
645 default:
646 fatal("Not implemented for %s", type2name(bt));
647 }
648 return NULL;
649 }
650
651 //=============================================================================
652 //------------------------------cmp--------------------------------------------
653 // Simplify a CmpI (compare 2 integers) node, based on local information.
654 // If both inputs are constants, compare them.
655 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const {
656 const TypeInt *r0 = t1->is_int(); // Handy access
657 const TypeInt *r1 = t2->is_int();
658
659 if( r0->_hi < r1->_lo ) // Range is always low?
660 return TypeInt::CC_LT;
661 else if( r0->_lo > r1->_hi ) // Range is always high?
662 return TypeInt::CC_GT;
663
664 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
665 assert(r0->get_con() == r1->get_con(), "must be equal");
666 return TypeInt::CC_EQ; // Equal results.
667 } else if( r0->_hi == r1->_lo ) // Range is never high?
668 return TypeInt::CC_LE;
669 else if( r0->_lo == r1->_hi ) // Range is never low?
670 return TypeInt::CC_GE;
671 return TypeInt::CC; // else use worst case results
672 }
673
674 // Simplify a CmpU (compare 2 integers) node, based on local information.
675 // If both inputs are constants, compare them.
676 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const {
677 assert(!t1->isa_ptr(), "obsolete usage of CmpU");
678
679 // comparing two unsigned ints
680 const TypeInt *r0 = t1->is_int(); // Handy access
681 const TypeInt *r1 = t2->is_int();
682
683 // Current installed version
684 // Compare ranges for non-overlap
685 juint lo0 = r0->_lo;
686 juint hi0 = r0->_hi;
687 juint lo1 = r1->_lo;
688 juint hi1 = r1->_hi;
689
690 // If either one has both negative and positive values,
691 // it therefore contains both 0 and -1, and since [0..-1] is the
692 // full unsigned range, the type must act as an unsigned bottom.
693 bool bot0 = ((jint)(lo0 ^ hi0) < 0);
694 bool bot1 = ((jint)(lo1 ^ hi1) < 0);
695
696 if (bot0 || bot1) {
697 // All unsigned values are LE -1 and GE 0.
698 if (lo0 == 0 && hi0 == 0) {
699 return TypeInt::CC_LE; // 0 <= bot
700 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) {
701 return TypeInt::CC_GE; // -1 >= bot
702 } else if (lo1 == 0 && hi1 == 0) {
703 return TypeInt::CC_GE; // bot >= 0
704 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) {
705 return TypeInt::CC_LE; // bot <= -1
706 }
707 } else {
708 // We can use ranges of the form [lo..hi] if signs are the same.
709 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
710 // results are reversed, '-' > '+' for unsigned compare
711 if (hi0 < lo1) {
712 return TypeInt::CC_LT; // smaller
713 } else if (lo0 > hi1) {
714 return TypeInt::CC_GT; // greater
715 } else if (hi0 == lo1 && lo0 == hi1) {
716 return TypeInt::CC_EQ; // Equal results
717 } else if (lo0 >= hi1) {
718 return TypeInt::CC_GE;
719 } else if (hi0 <= lo1) {
720 // Check for special case in Hashtable::get. (See below.)
721 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
722 return TypeInt::CC_LT;
723 return TypeInt::CC_LE;
724 }
725 }
726 // Check for special case in Hashtable::get - the hash index is
727 // mod'ed to the table size so the following range check is useless.
728 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have
729 // to be positive.
730 // (This is a gross hack, since the sub method never
731 // looks at the structure of the node in any other case.)
732 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
733 return TypeInt::CC_LT;
734 return TypeInt::CC; // else use worst case results
735 }
736
737 const Type* CmpUNode::Value(PhaseGVN* phase) const {
738 const Type* t = SubNode::Value_common(phase);
739 if (t != NULL) {
740 return t;
741 }
742 const Node* in1 = in(1);
743 const Node* in2 = in(2);
744 const Type* t1 = phase->type(in1);
745 const Type* t2 = phase->type(in2);
746 assert(t1->isa_int(), "CmpU has only Int type inputs");
747 if (t2 == TypeInt::INT) { // Compare to bottom?
748 return bottom_type();
749 }
750 uint in1_op = in1->Opcode();
751 if (in1_op == Op_AddI || in1_op == Op_SubI) {
752 // The problem rise when result of AddI(SubI) may overflow
753 // signed integer value. Let say the input type is
754 // [256, maxint] then +128 will create 2 ranges due to
755 // overflow: [minint, minint+127] and [384, maxint].
756 // But C2 type system keep only 1 type range and as result
757 // it use general [minint, maxint] for this case which we
758 // can't optimize.
759 //
760 // Make 2 separate type ranges based on types of AddI(SubI) inputs
761 // and compare results of their compare. If results are the same
762 // CmpU node can be optimized.
763 const Node* in11 = in1->in(1);
764 const Node* in12 = in1->in(2);
765 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11);
766 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12);
767 // Skip cases when input types are top or bottom.
768 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) &&
769 (t12 != Type::TOP) && (t12 != TypeInt::INT)) {
770 const TypeInt *r0 = t11->is_int();
771 const TypeInt *r1 = t12->is_int();
772 jlong lo_r0 = r0->_lo;
773 jlong hi_r0 = r0->_hi;
774 jlong lo_r1 = r1->_lo;
775 jlong hi_r1 = r1->_hi;
776 if (in1_op == Op_SubI) {
777 jlong tmp = hi_r1;
778 hi_r1 = -lo_r1;
779 lo_r1 = -tmp;
780 // Note, for substructing [minint,x] type range
781 // long arithmetic provides correct overflow answer.
782 // The confusion come from the fact that in 32-bit
783 // -minint == minint but in 64-bit -minint == maxint+1.
784 }
785 jlong lo_long = lo_r0 + lo_r1;
786 jlong hi_long = hi_r0 + hi_r1;
787 int lo_tr1 = min_jint;
788 int hi_tr1 = (int)hi_long;
789 int lo_tr2 = (int)lo_long;
790 int hi_tr2 = max_jint;
791 bool underflow = lo_long != (jlong)lo_tr2;
792 bool overflow = hi_long != (jlong)hi_tr1;
793 // Use sub(t1, t2) when there is no overflow (one type range)
794 // or when both overflow and underflow (too complex).
795 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) {
796 // Overflow only on one boundary, compare 2 separate type ranges.
797 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
798 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w);
799 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w);
800 const TypeInt* cmp1 = sub(tr1, t2)->is_int();
801 const TypeInt* cmp2 = sub(tr2, t2)->is_int();
802 // compute union, so that cmp handles all possible results from the two cases
803 return cmp1->meet(cmp2);
804 }
805 }
806 }
807
808 return sub(t1, t2); // Local flavor of type subtraction
809 }
810
811 bool CmpUNode::is_index_range_check() const {
812 // Check for the "(X ModI Y) CmpU Y" shape
813 return (in(1)->Opcode() == Op_ModI &&
814 in(1)->in(2)->eqv_uncast(in(2)));
815 }
816
817 //------------------------------Idealize---------------------------------------
818 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
819 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) {
820 switch (in(1)->Opcode()) {
821 case Op_CmpU3: // Collapse a CmpU3/CmpI into a CmpU
822 return new CmpUNode(in(1)->in(1),in(1)->in(2));
823 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL
824 return new CmpLNode(in(1)->in(1),in(1)->in(2));
825 case Op_CmpUL3: // Collapse a CmpUL3/CmpI into a CmpUL
826 return new CmpULNode(in(1)->in(1),in(1)->in(2));
827 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF
828 return new CmpFNode(in(1)->in(1),in(1)->in(2));
829 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD
830 return new CmpDNode(in(1)->in(1),in(1)->in(2));
831 //case Op_SubI:
832 // If (x - y) cannot overflow, then ((x - y) <?> 0)
833 // can be turned into (x <?> y).
834 // This is handled (with more general cases) by Ideal_sub_algebra.
835 }
836 }
837 return NULL; // No change
838 }
839
840 //------------------------------Ideal------------------------------------------
841 Node* CmpLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
842 Node* a = NULL;
843 Node* b = NULL;
844 if (is_double_null_check(phase, a, b) && (phase->type(a)->is_zero_type() || phase->type(b)->is_zero_type())) {
845 // Degraded to a simple null check, use old acmp
846 return new CmpPNode(a, b);
847 }
848 const TypeLong *t2 = phase->type(in(2))->isa_long();
849 if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) {
850 const jlong con = t2->get_con();
851 if (con >= min_jint && con <= max_jint) {
852 return new CmpINode(in(1)->in(1), phase->intcon((jint)con));
853 }
854 }
855 return NULL;
856 }
857
858 // Match double null check emitted by Compile::optimize_acmp()
859 bool CmpLNode::is_double_null_check(PhaseGVN* phase, Node*& a, Node*& b) const {
860 if (in(1)->Opcode() == Op_OrL &&
861 in(1)->in(1)->Opcode() == Op_CastP2X &&
862 in(1)->in(2)->Opcode() == Op_CastP2X &&
863 in(2)->bottom_type()->is_zero_type()) {
864 assert(EnableValhalla, "unexpected double null check");
865 a = in(1)->in(1)->in(1);
866 b = in(1)->in(2)->in(1);
867 return true;
868 }
869 return false;
870 }
871
872 //------------------------------Value------------------------------------------
873 const Type* CmpLNode::Value(PhaseGVN* phase) const {
874 Node* a = NULL;
875 Node* b = NULL;
876 if (is_double_null_check(phase, a, b) && (!phase->type(a)->maybe_null() || !phase->type(b)->maybe_null())) {
877 // One operand is never NULL, emit constant false
878 return TypeInt::CC_GT;
879 }
880 return SubNode::Value(phase);
881 }
882
883 //=============================================================================
884 // Simplify a CmpL (compare 2 longs ) node, based on local information.
885 // If both inputs are constants, compare them.
886 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const {
887 const TypeLong *r0 = t1->is_long(); // Handy access
888 const TypeLong *r1 = t2->is_long();
889
890 if( r0->_hi < r1->_lo ) // Range is always low?
891 return TypeInt::CC_LT;
892 else if( r0->_lo > r1->_hi ) // Range is always high?
893 return TypeInt::CC_GT;
894
895 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
896 assert(r0->get_con() == r1->get_con(), "must be equal");
897 return TypeInt::CC_EQ; // Equal results.
898 } else if( r0->_hi == r1->_lo ) // Range is never high?
899 return TypeInt::CC_LE;
900 else if( r0->_lo == r1->_hi ) // Range is never low?
901 return TypeInt::CC_GE;
902 return TypeInt::CC; // else use worst case results
903 }
904
905
906 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information.
907 // If both inputs are constants, compare them.
908 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const {
909 assert(!t1->isa_ptr(), "obsolete usage of CmpUL");
910
911 // comparing two unsigned longs
912 const TypeLong* r0 = t1->is_long(); // Handy access
913 const TypeLong* r1 = t2->is_long();
914
915 // Current installed version
916 // Compare ranges for non-overlap
917 julong lo0 = r0->_lo;
918 julong hi0 = r0->_hi;
919 julong lo1 = r1->_lo;
920 julong hi1 = r1->_hi;
921
922 // If either one has both negative and positive values,
923 // it therefore contains both 0 and -1, and since [0..-1] is the
924 // full unsigned range, the type must act as an unsigned bottom.
925 bool bot0 = ((jlong)(lo0 ^ hi0) < 0);
926 bool bot1 = ((jlong)(lo1 ^ hi1) < 0);
927
928 if (bot0 || bot1) {
929 // All unsigned values are LE -1 and GE 0.
930 if (lo0 == 0 && hi0 == 0) {
931 return TypeInt::CC_LE; // 0 <= bot
932 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) {
933 return TypeInt::CC_GE; // -1 >= bot
934 } else if (lo1 == 0 && hi1 == 0) {
935 return TypeInt::CC_GE; // bot >= 0
936 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) {
937 return TypeInt::CC_LE; // bot <= -1
938 }
939 } else {
940 // We can use ranges of the form [lo..hi] if signs are the same.
941 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
942 // results are reversed, '-' > '+' for unsigned compare
943 if (hi0 < lo1) {
944 return TypeInt::CC_LT; // smaller
945 } else if (lo0 > hi1) {
946 return TypeInt::CC_GT; // greater
947 } else if (hi0 == lo1 && lo0 == hi1) {
948 return TypeInt::CC_EQ; // Equal results
949 } else if (lo0 >= hi1) {
950 return TypeInt::CC_GE;
951 } else if (hi0 <= lo1) {
952 return TypeInt::CC_LE;
953 }
954 }
955
956 return TypeInt::CC; // else use worst case results
957 }
958
959 //=============================================================================
960 //------------------------------sub--------------------------------------------
961 // Simplify an CmpP (compare 2 pointers) node, based on local information.
962 // If both inputs are constants, compare them.
963 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const {
964 const TypePtr *r0 = t1->is_ptr(); // Handy access
965 const TypePtr *r1 = t2->is_ptr();
966
967 // Undefined inputs makes for an undefined result
968 if( TypePtr::above_centerline(r0->_ptr) ||
969 TypePtr::above_centerline(r1->_ptr) )
970 return Type::TOP;
971
972 if (r0 == r1 && r0->singleton()) {
973 // Equal pointer constants (klasses, nulls, etc.)
974 return TypeInt::CC_EQ;
975 }
976
977 // See if it is 2 unrelated classes.
978 const TypeOopPtr* p0 = r0->isa_oopptr();
979 const TypeOopPtr* p1 = r1->isa_oopptr();
980 const TypeKlassPtr* k0 = r0->isa_klassptr();
981 const TypeKlassPtr* k1 = r1->isa_klassptr();
982 if ((p0 && p1) || (k0 && k1)) {
983 if (p0 && p1) {
984 Node* in1 = in(1)->uncast();
985 Node* in2 = in(2)->uncast();
986 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1, NULL);
987 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2, NULL);
988 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, NULL)) {
989 return TypeInt::CC_GT; // different pointers
990 }
991 }
992 bool xklass0 = p0 ? p0->klass_is_exact() : k0->klass_is_exact();
993 bool xklass1 = p1 ? p1->klass_is_exact() : k1->klass_is_exact();
994 bool unrelated_classes = false;
995
996 if ((p0 && p0->is_same_java_type_as(p1)) ||
997 (k0 && k0->is_same_java_type_as(k1))) {
998 } else if ((p0 && !p1->maybe_java_subtype_of(p0) && !p0->maybe_java_subtype_of(p1)) ||
999 (k0 && !k1->maybe_java_subtype_of(k0) && !k0->maybe_java_subtype_of(k1))) {
1000 unrelated_classes = true;
1001 } else if ((p0 && !p1->maybe_java_subtype_of(p0)) ||
1002 (k0 && !k1->maybe_java_subtype_of(k0))) {
1003 unrelated_classes = xklass1;
1004 } else if ((p0 && !p0->maybe_java_subtype_of(p1)) ||
1005 (k0 && !k0->maybe_java_subtype_of(k1))) {
1006 unrelated_classes = xklass0;
1007 }
1008 if (!unrelated_classes) {
1009 // Handle inline type arrays
1010 if ((r0->flatten_array() && r1->not_flatten_array()) ||
1011 (r1->flatten_array() && r0->not_flatten_array())) {
1012 // One type is flattened in arrays but the other type is not. Must be unrelated.
1013 unrelated_classes = true;
1014 } else if ((r0->is_not_flat() && r1->is_flat()) ||
1015 (r1->is_not_flat() && r0->is_flat())) {
1016 // One type is a non-flattened array and the other type is a flattened array. Must be unrelated.
1017 unrelated_classes = true;
1018 } else if ((r0->is_not_null_free() && r1->is_null_free()) ||
1019 (r1->is_not_null_free() && r0->is_null_free())) {
1020 // One type is a nullable array and the other type is a null-free array. Must be unrelated.
1021 unrelated_classes = true;
1022 }
1023 }
1024 if (unrelated_classes) {
1025 // The oops classes are known to be unrelated. If the joined PTRs of
1026 // two oops is not Null and not Bottom, then we are sure that one
1027 // of the two oops is non-null, and the comparison will always fail.
1028 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
1029 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
1030 return TypeInt::CC_GT;
1031 }
1032 }
1033 }
1034
1035 // Known constants can be compared exactly
1036 // Null can be distinguished from any NotNull pointers
1037 // Unknown inputs makes an unknown result
1038 if( r0->singleton() ) {
1039 intptr_t bits0 = r0->get_con();
1040 if( r1->singleton() )
1041 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
1042 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1043 } else if( r1->singleton() ) {
1044 intptr_t bits1 = r1->get_con();
1045 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1046 } else
1047 return TypeInt::CC;
1048 }
1049
1050 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) {
1051 // Return the klass node for (indirect load from OopHandle)
1052 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
1053 // or NULL if not matching.
1054 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1055 n = bs->step_over_gc_barrier(n);
1056
1057 if (n->Opcode() != Op_LoadP) return NULL;
1058
1059 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1060 if (!tp || tp->instance_klass() != phase->C->env()->Class_klass()) return NULL;
1061
1062 Node* adr = n->in(MemNode::Address);
1063 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier.
1064 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return NULL;
1065 adr = adr->in(MemNode::Address);
1066
1067 intptr_t off = 0;
1068 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off);
1069 if (k == NULL) return NULL;
1070 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr();
1071 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return NULL;
1072
1073 // We've found the klass node of a Java mirror load.
1074 return k;
1075 }
1076
1077 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) {
1078 // for ConP(Foo.class) return ConP(Foo.klass)
1079 // otherwise return NULL
1080 if (!n->is_Con()) return NULL;
1081
1082 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1083 if (!tp) return NULL;
1084
1085 ciType* mirror_type = tp->java_mirror_type();
1086 // TypeInstPtr::java_mirror_type() returns non-NULL for compile-
1087 // time Class constants only.
1088 if (!mirror_type) return NULL;
1089
1090 // x.getClass() == int.class can never be true (for all primitive types)
1091 // Return a ConP(NULL) node for this case.
1092 if (mirror_type->is_classless()) {
1093 return phase->makecon(TypePtr::NULL_PTR);
1094 }
1095
1096 // return the ConP(Foo.klass)
1097 assert(mirror_type->is_klass(), "mirror_type should represent a Klass*");
1098 return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass()));
1099 }
1100
1101 //------------------------------Ideal------------------------------------------
1102 // Normalize comparisons between Java mirror loads to compare the klass instead.
1103 //
1104 // Also check for the case of comparing an unknown klass loaded from the primary
1105 // super-type array vs a known klass with no subtypes. This amounts to
1106 // checking to see an unknown klass subtypes a known klass with no subtypes;
1107 // this only happens on an exact match. We can shorten this test by 1 load.
1108 Node* CmpPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1109 // TODO 8284443 in(1) could be cast?
1110 if (in(1)->is_InlineType() && phase->type(in(2))->is_zero_type()) {
1111 // Null checking a scalarized but nullable inline type. Check the IsInit
1112 // input instead of the oop input to avoid keeping buffer allocations alive.
1113 return new CmpINode(in(1)->as_InlineType()->get_is_init(), phase->intcon(0));
1114 }
1115
1116 // Normalize comparisons between Java mirrors into comparisons of the low-
1117 // level klass, where a dependent load could be shortened.
1118 //
1119 // The new pattern has a nice effect of matching the same pattern used in the
1120 // fast path of instanceof/checkcast/Class.isInstance(), which allows
1121 // redundant exact type check be optimized away by GVN.
1122 // For example, in
1123 // if (x.getClass() == Foo.class) {
1124 // Foo foo = (Foo) x;
1125 // // ... use a ...
1126 // }
1127 // a CmpPNode could be shared between if_acmpne and checkcast
1128 {
1129 Node* k1 = isa_java_mirror_load(phase, in(1));
1130 Node* k2 = isa_java_mirror_load(phase, in(2));
1131 Node* conk2 = isa_const_java_mirror(phase, in(2));
1132
1133 if (k1 && (k2 || conk2)) {
1134 Node* lhs = k1;
1135 Node* rhs = (k2 != NULL) ? k2 : conk2;
1136 set_req_X(1, lhs, phase);
1137 set_req_X(2, rhs, phase);
1138 return this;
1139 }
1140 }
1141
1142 // Constant pointer on right?
1143 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
1144 if (t2 == NULL || !t2->klass_is_exact())
1145 return NULL;
1146 // Get the constant klass we are comparing to.
1147 ciKlass* superklass = t2->exact_klass();
1148
1149 // Now check for LoadKlass on left.
1150 Node* ldk1 = in(1);
1151 if (ldk1->is_DecodeNKlass()) {
1152 ldk1 = ldk1->in(1);
1153 if (ldk1->Opcode() != Op_LoadNKlass )
1154 return NULL;
1155 } else if (ldk1->Opcode() != Op_LoadKlass )
1156 return NULL;
1157 // Take apart the address of the LoadKlass:
1158 Node* adr1 = ldk1->in(MemNode::Address);
1159 intptr_t con2 = 0;
1160 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
1161 if (ldk2 == NULL)
1162 return NULL;
1163 if (con2 == oopDesc::klass_offset_in_bytes()) {
1164 // We are inspecting an object's concrete class.
1165 // Short-circuit the check if the query is abstract.
1166 if (superklass->is_interface() ||
1167 superklass->is_abstract()) {
1168 // Make it come out always false:
1169 this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
1170 return this;
1171 }
1172 }
1173
1174 // Check for a LoadKlass from primary supertype array.
1175 // Any nested loadklass from loadklass+con must be from the p.s. array.
1176 if (ldk2->is_DecodeNKlass()) {
1177 // Keep ldk2 as DecodeN since it could be used in CmpP below.
1178 if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
1179 return NULL;
1180 } else if (ldk2->Opcode() != Op_LoadKlass)
1181 return NULL;
1182
1183 // Verify that we understand the situation
1184 if (con2 != (intptr_t) superklass->super_check_offset())
1185 return NULL; // Might be element-klass loading from array klass
1186
1187 // Do not fold the subtype check to an array klass pointer comparison for [V? arrays.
1188 // [QMyValue is a subtype of [LMyValue but the klass for [QMyValue is not equal to
1189 // the klass for [LMyValue. Do not bypass the klass load from the primary supertype array.
1190 if (superklass->is_obj_array_klass() && !superklass->as_array_klass()->is_elem_null_free() &&
1191 superklass->as_array_klass()->element_klass()->is_inlinetype()) {
1192 return NULL;
1193 }
1194
1195 // If 'superklass' has no subklasses and is not an interface, then we are
1196 // assured that the only input which will pass the type check is
1197 // 'superklass' itself.
1198 //
1199 // We could be more liberal here, and allow the optimization on interfaces
1200 // which have a single implementor. This would require us to increase the
1201 // expressiveness of the add_dependency() mechanism.
1202 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now.
1203
1204 // Object arrays must have their base element have no subtypes
1205 while (superklass->is_obj_array_klass()) {
1206 ciType* elem = superklass->as_obj_array_klass()->element_type();
1207 superklass = elem->as_klass();
1208 }
1209 if (superklass->is_instance_klass()) {
1210 ciInstanceKlass* ik = superklass->as_instance_klass();
1211 if (ik->has_subklass() || ik->is_interface()) return NULL;
1212 // Add a dependency if there is a chance that a subclass will be added later.
1213 if (!ik->is_final()) {
1214 phase->C->dependencies()->assert_leaf_type(ik);
1215 }
1216 }
1217
1218 // Bypass the dependent load, and compare directly
1219 this->set_req(1,ldk2);
1220
1221 return this;
1222 }
1223
1224 //=============================================================================
1225 //------------------------------sub--------------------------------------------
1226 // Simplify an CmpN (compare 2 pointers) node, based on local information.
1227 // If both inputs are constants, compare them.
1228 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
1229 ShouldNotReachHere();
1230 return bottom_type();
1231 }
1232
1233 //------------------------------Ideal------------------------------------------
1234 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1235 return NULL;
1236 }
1237
1238 //=============================================================================
1239 //------------------------------Value------------------------------------------
1240 // Simplify an CmpF (compare 2 floats ) node, based on local information.
1241 // If both inputs are constants, compare them.
1242 const Type* CmpFNode::Value(PhaseGVN* phase) const {
1243 const Node* in1 = in(1);
1244 const Node* in2 = in(2);
1245 // Either input is TOP ==> the result is TOP
1246 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1247 if( t1 == Type::TOP ) return Type::TOP;
1248 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1249 if( t2 == Type::TOP ) return Type::TOP;
1250
1251 // Not constants? Don't know squat - even if they are the same
1252 // value! If they are NaN's they compare to LT instead of EQ.
1253 const TypeF *tf1 = t1->isa_float_constant();
1254 const TypeF *tf2 = t2->isa_float_constant();
1255 if( !tf1 || !tf2 ) return TypeInt::CC;
1256
1257 // This implements the Java bytecode fcmpl, so unordered returns -1.
1258 if( tf1->is_nan() || tf2->is_nan() )
1259 return TypeInt::CC_LT;
1260
1261 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
1262 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
1263 assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
1264 return TypeInt::CC_EQ;
1265 }
1266
1267
1268 //=============================================================================
1269 //------------------------------Value------------------------------------------
1270 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
1271 // If both inputs are constants, compare them.
1272 const Type* CmpDNode::Value(PhaseGVN* phase) const {
1273 const Node* in1 = in(1);
1274 const Node* in2 = in(2);
1275 // Either input is TOP ==> the result is TOP
1276 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1277 if( t1 == Type::TOP ) return Type::TOP;
1278 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1279 if( t2 == Type::TOP ) return Type::TOP;
1280
1281 // Not constants? Don't know squat - even if they are the same
1282 // value! If they are NaN's they compare to LT instead of EQ.
1283 const TypeD *td1 = t1->isa_double_constant();
1284 const TypeD *td2 = t2->isa_double_constant();
1285 if( !td1 || !td2 ) return TypeInt::CC;
1286
1287 // This implements the Java bytecode dcmpl, so unordered returns -1.
1288 if( td1->is_nan() || td2->is_nan() )
1289 return TypeInt::CC_LT;
1290
1291 if( td1->_d < td2->_d ) return TypeInt::CC_LT;
1292 if( td1->_d > td2->_d ) return TypeInt::CC_GT;
1293 assert( td1->_d == td2->_d, "do not understand FP behavior" );
1294 return TypeInt::CC_EQ;
1295 }
1296
1297 //------------------------------Ideal------------------------------------------
1298 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
1299 // Check if we can change this to a CmpF and remove a ConvD2F operation.
1300 // Change (CMPD (F2D (float)) (ConD value))
1301 // To (CMPF (float) (ConF value))
1302 // Valid when 'value' does not lose precision as a float.
1303 // Benefits: eliminates conversion, does not require 24-bit mode
1304
1305 // NaNs prevent commuting operands. This transform works regardless of the
1306 // order of ConD and ConvF2D inputs by preserving the original order.
1307 int idx_f2d = 1; // ConvF2D on left side?
1308 if( in(idx_f2d)->Opcode() != Op_ConvF2D )
1309 idx_f2d = 2; // No, swap to check for reversed args
1310 int idx_con = 3-idx_f2d; // Check for the constant on other input
1311
1312 if( ConvertCmpD2CmpF &&
1313 in(idx_f2d)->Opcode() == Op_ConvF2D &&
1314 in(idx_con)->Opcode() == Op_ConD ) {
1315 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
1316 double t2_value_as_double = t2->_d;
1317 float t2_value_as_float = (float)t2_value_as_double;
1318 if( t2_value_as_double == (double)t2_value_as_float ) {
1319 // Test value can be represented as a float
1320 // Eliminate the conversion to double and create new comparison
1321 Node *new_in1 = in(idx_f2d)->in(1);
1322 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
1323 if( idx_f2d != 1 ) { // Must flip args to match original order
1324 Node *tmp = new_in1;
1325 new_in1 = new_in2;
1326 new_in2 = tmp;
1327 }
1328 CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
1329 ? new CmpF3Node( new_in1, new_in2 )
1330 : new CmpFNode ( new_in1, new_in2 ) ;
1331 return new_cmp; // Changed to CmpFNode
1332 }
1333 // Testing value required the precision of a double
1334 }
1335 return NULL; // No change
1336 }
1337
1338 //=============================================================================
1339 //------------------------------Value------------------------------------------
1340 const Type* FlatArrayCheckNode::Value(PhaseGVN* phase) const {
1341 bool all_not_flat = true;
1342 for (uint i = ArrayOrKlass; i < req(); ++i) {
1343 const Type* t = phase->type(in(i));
1344 if (t == Type::TOP) {
1345 return Type::TOP;
1346 }
1347 if (t->is_ptr()->is_flat()) {
1348 // One of the input arrays is flat, check always passes
1349 return TypeInt::CC_EQ;
1350 } else if (!t->is_ptr()->is_not_flat()) {
1351 // One of the input arrays might be flat
1352 all_not_flat = false;
1353 }
1354 }
1355 if (all_not_flat) {
1356 // None of the input arrays can be flat, check always fails
1357 return TypeInt::CC_GT;
1358 }
1359 return TypeInt::CC;
1360 }
1361
1362 //------------------------------Ideal------------------------------------------
1363 Node* FlatArrayCheckNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1364 bool changed = false;
1365 // Remove inputs that are known to be non-flat
1366 for (uint i = ArrayOrKlass; i < req(); ++i) {
1367 const Type* t = phase->type(in(i));
1368 if (t->isa_ptr() && t->is_ptr()->is_not_flat()) {
1369 del_req(i--);
1370 changed = true;
1371 }
1372 }
1373 return changed ? this : NULL;
1374 }
1375
1376 //=============================================================================
1377 //------------------------------cc2logical-------------------------------------
1378 // Convert a condition code type to a logical type
1379 const Type *BoolTest::cc2logical( const Type *CC ) const {
1380 if( CC == Type::TOP ) return Type::TOP;
1381 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
1382 const TypeInt *ti = CC->is_int();
1383 if( ti->is_con() ) { // Only 1 kind of condition codes set?
1384 // Match low order 2 bits
1385 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
1386 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result
1387 return TypeInt::make(tmp); // Boolean result
1388 }
1389
1390 if( CC == TypeInt::CC_GE ) {
1391 if( _test == ge ) return TypeInt::ONE;
1392 if( _test == lt ) return TypeInt::ZERO;
1393 }
1394 if( CC == TypeInt::CC_LE ) {
1395 if( _test == le ) return TypeInt::ONE;
1396 if( _test == gt ) return TypeInt::ZERO;
1397 }
1398
1399 return TypeInt::BOOL;
1400 }
1401
1402 //------------------------------dump_spec-------------------------------------
1403 // Print special per-node info
1404 void BoolTest::dump_on(outputStream *st) const {
1405 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"};
1406 st->print("%s", msg[_test]);
1407 }
1408
1409 // Returns the logical AND of two tests (or 'never' if both tests can never be true).
1410 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'.
1411 BoolTest::mask BoolTest::merge(BoolTest other) const {
1412 const mask res[illegal+1][illegal+1] = {
1413 // eq, gt, of, lt, ne, le, nof, ge, never, illegal
1414 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq
1415 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt
1416 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of
1417 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt
1418 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne
1419 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le
1420 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof
1421 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge
1422 {never, never, never, never, never, never, never, never, never, illegal}, // never
1423 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal
1424 return res[_test][other._test];
1425 }
1426
1427 //=============================================================================
1428 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
1429 uint BoolNode::size_of() const { return sizeof(BoolNode); }
1430
1431 //------------------------------operator==-------------------------------------
1432 bool BoolNode::cmp( const Node &n ) const {
1433 const BoolNode *b = (const BoolNode *)&n; // Cast up
1434 return (_test._test == b->_test._test);
1435 }
1436
1437 //-------------------------------make_predicate--------------------------------
1438 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1439 if (test_value->is_Con()) return test_value;
1440 if (test_value->is_Bool()) return test_value;
1441 if (test_value->is_CMove() &&
1442 test_value->in(CMoveNode::Condition)->is_Bool()) {
1443 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool();
1444 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1445 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1446 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1447 return bol;
1448 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1449 return phase->transform( bol->negate(phase) );
1450 }
1451 // Else fall through. The CMove gets in the way of the test.
1452 // It should be the case that make_predicate(bol->as_int_value()) == bol.
1453 }
1454 Node* cmp = new CmpINode(test_value, phase->intcon(0));
1455 cmp = phase->transform(cmp);
1456 Node* bol = new BoolNode(cmp, BoolTest::ne);
1457 return phase->transform(bol);
1458 }
1459
1460 //--------------------------------as_int_value---------------------------------
1461 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1462 // Inverse to make_predicate. The CMove probably boils down to a Conv2B.
1463 Node* cmov = CMoveNode::make(NULL, this,
1464 phase->intcon(0), phase->intcon(1),
1465 TypeInt::BOOL);
1466 return phase->transform(cmov);
1467 }
1468
1469 //----------------------------------negate-------------------------------------
1470 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1471 return new BoolNode(in(1), _test.negate());
1472 }
1473
1474 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub
1475 // overflows and we can prove that C is not in the two resulting ranges.
1476 // This optimization is similar to the one performed by CmpUNode::Value().
1477 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op,
1478 int cmp1_op, const TypeInt* cmp2_type) {
1479 // Only optimize eq/ne integer comparison of add/sub
1480 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1481 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) {
1482 // Skip cases were inputs of add/sub are not integers or of bottom type
1483 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int();
1484 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int();
1485 if ((r0 != NULL) && (r0 != TypeInt::INT) &&
1486 (r1 != NULL) && (r1 != TypeInt::INT) &&
1487 (cmp2_type != TypeInt::INT)) {
1488 // Compute exact (long) type range of add/sub result
1489 jlong lo_long = r0->_lo;
1490 jlong hi_long = r0->_hi;
1491 if (cmp1_op == Op_AddI) {
1492 lo_long += r1->_lo;
1493 hi_long += r1->_hi;
1494 } else {
1495 lo_long -= r1->_hi;
1496 hi_long -= r1->_lo;
1497 }
1498 // Check for over-/underflow by casting to integer
1499 int lo_int = (int)lo_long;
1500 int hi_int = (int)hi_long;
1501 bool underflow = lo_long != (jlong)lo_int;
1502 bool overflow = hi_long != (jlong)hi_int;
1503 if ((underflow != overflow) && (hi_int < lo_int)) {
1504 // Overflow on one boundary, compute resulting type ranges:
1505 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT]
1506 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
1507 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w);
1508 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w);
1509 // Compare second input of cmp to both type ranges
1510 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type);
1511 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type);
1512 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) {
1513 // The result of the add/sub will never equal cmp2. Replace BoolNode
1514 // by false (0) if it tests for equality and by true (1) otherwise.
1515 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1);
1516 }
1517 }
1518 }
1519 }
1520 return NULL;
1521 }
1522
1523 static bool is_counted_loop_cmp(Node *cmp) {
1524 Node *n = cmp->in(1)->in(1);
1525 return n != NULL &&
1526 n->is_Phi() &&
1527 n->in(0) != NULL &&
1528 n->in(0)->is_CountedLoop() &&
1529 n->in(0)->as_CountedLoop()->phi() == n;
1530 }
1531
1532 //------------------------------Ideal------------------------------------------
1533 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1534 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1535 // This moves the constant to the right. Helps value-numbering.
1536 Node *cmp = in(1);
1537 if( !cmp->is_Sub() ) return NULL;
1538 int cop = cmp->Opcode();
1539 if( cop == Op_FastLock || cop == Op_FastUnlock || cmp->is_SubTypeCheck()) return NULL;
1540 Node *cmp1 = cmp->in(1);
1541 Node *cmp2 = cmp->in(2);
1542 if( !cmp1 ) return NULL;
1543
1544 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) {
1545 return NULL;
1546 }
1547
1548 const int cmp1_op = cmp1->Opcode();
1549 const int cmp2_op = cmp2->Opcode();
1550
1551 // Constant on left?
1552 Node *con = cmp1;
1553 // Move constants to the right of compare's to canonicalize.
1554 // Do not muck with Opaque1 nodes, as this indicates a loop
1555 // guard that cannot change shape.
1556 if( con->is_Con() && !cmp2->is_Con() && cmp2_op != Op_Opaque1 &&
1557 // Because of NaN's, CmpD and CmpF are not commutative
1558 cop != Op_CmpD && cop != Op_CmpF &&
1559 // Protect against swapping inputs to a compare when it is used by a
1560 // counted loop exit, which requires maintaining the loop-limit as in(2)
1561 !is_counted_loop_exit_test() ) {
1562 // Ok, commute the constant to the right of the cmp node.
1563 // Clone the Node, getting a new Node of the same class
1564 cmp = cmp->clone();
1565 // Swap inputs to the clone
1566 cmp->swap_edges(1, 2);
1567 cmp = phase->transform( cmp );
1568 return new BoolNode( cmp, _test.commute() );
1569 }
1570
1571 // Change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1572 if (cop == Op_CmpI &&
1573 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1574 cmp1_op == Op_AndI && cmp2_op == Op_ConI &&
1575 cmp1->in(2)->Opcode() == Op_ConI) {
1576 const TypeInt *t12 = phase->type(cmp2)->isa_int();
1577 const TypeInt *t112 = phase->type(cmp1->in(2))->isa_int();
1578 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1579 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1580 Node *ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1581 return new BoolNode(ncmp, _test.negate());
1582 }
1583 }
1584
1585 // Same for long type: change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1586 if (cop == Op_CmpL &&
1587 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1588 cmp1_op == Op_AndL && cmp2_op == Op_ConL &&
1589 cmp1->in(2)->Opcode() == Op_ConL) {
1590 const TypeLong *t12 = phase->type(cmp2)->isa_long();
1591 const TypeLong *t112 = phase->type(cmp1->in(2))->isa_long();
1592 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1593 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1594 Node *ncmp = phase->transform(new CmpLNode(cmp1, phase->longcon(0)));
1595 return new BoolNode(ncmp, _test.negate());
1596 }
1597 }
1598
1599 // Change "cmp (add X min_jint) (add Y min_jint)" into "cmpu X Y"
1600 // and "cmp (add X min_jint) c" into "cmpu X (c + min_jint)"
1601 if (cop == Op_CmpI &&
1602 cmp1_op == Op_AddI &&
1603 phase->type(cmp1->in(2)) == TypeInt::MIN) {
1604 if (cmp2_op == Op_ConI) {
1605 Node* ncmp2 = phase->intcon(java_add(cmp2->get_int(), min_jint));
1606 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), ncmp2));
1607 return new BoolNode(ncmp, _test._test);
1608 } else if (cmp2_op == Op_AddI &&
1609 phase->type(cmp2->in(2)) == TypeInt::MIN) {
1610 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), cmp2->in(1)));
1611 return new BoolNode(ncmp, _test._test);
1612 }
1613 }
1614
1615 // Change "cmp (add X min_jlong) (add Y min_jlong)" into "cmpu X Y"
1616 // and "cmp (add X min_jlong) c" into "cmpu X (c + min_jlong)"
1617 if (cop == Op_CmpL &&
1618 cmp1_op == Op_AddL &&
1619 phase->type(cmp1->in(2)) == TypeLong::MIN) {
1620 if (cmp2_op == Op_ConL) {
1621 Node* ncmp2 = phase->longcon(java_add(cmp2->get_long(), min_jlong));
1622 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), ncmp2));
1623 return new BoolNode(ncmp, _test._test);
1624 } else if (cmp2_op == Op_AddL &&
1625 phase->type(cmp2->in(2)) == TypeLong::MIN) {
1626 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), cmp2->in(1)));
1627 return new BoolNode(ncmp, _test._test);
1628 }
1629 }
1630
1631 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1632 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the
1633 // test instead.
1634 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1635 if (cmp2_type == NULL) return NULL;
1636 Node* j_xor = cmp1;
1637 if( cmp2_type == TypeInt::ZERO &&
1638 cmp1_op == Op_XorI &&
1639 j_xor->in(1) != j_xor && // An xor of itself is dead
1640 phase->type( j_xor->in(1) ) == TypeInt::BOOL &&
1641 phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1642 (_test._test == BoolTest::eq ||
1643 _test._test == BoolTest::ne) ) {
1644 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2));
1645 return new BoolNode( ncmp, _test.negate() );
1646 }
1647
1648 // Change ((x & m) u<= m) or ((m & x) u<= m) to always true
1649 // Same with ((x & m) u< m+1) and ((m & x) u< m+1)
1650 if (cop == Op_CmpU &&
1651 cmp1_op == Op_AndI) {
1652 Node* bound = NULL;
1653 if (_test._test == BoolTest::le) {
1654 bound = cmp2;
1655 } else if (_test._test == BoolTest::lt &&
1656 cmp2->Opcode() == Op_AddI &&
1657 cmp2->in(2)->find_int_con(0) == 1) {
1658 bound = cmp2->in(1);
1659 }
1660 if (cmp1->in(2) == bound || cmp1->in(1) == bound) {
1661 return ConINode::make(1);
1662 }
1663 }
1664
1665 // Change ((x & (m - 1)) u< m) into (m > 0)
1666 // This is the off-by-one variant of the above
1667 if (cop == Op_CmpU &&
1668 _test._test == BoolTest::lt &&
1669 cmp1_op == Op_AndI) {
1670 Node* l = cmp1->in(1);
1671 Node* r = cmp1->in(2);
1672 for (int repeat = 0; repeat < 2; repeat++) {
1673 bool match = r->Opcode() == Op_AddI && r->in(2)->find_int_con(0) == -1 &&
1674 r->in(1) == cmp2;
1675 if (match) {
1676 // arraylength known to be non-negative, so a (arraylength != 0) is sufficient,
1677 // but to be compatible with the array range check pattern, use (arraylength u> 0)
1678 Node* ncmp = cmp2->Opcode() == Op_LoadRange
1679 ? phase->transform(new CmpUNode(cmp2, phase->intcon(0)))
1680 : phase->transform(new CmpINode(cmp2, phase->intcon(0)));
1681 return new BoolNode(ncmp, BoolTest::gt);
1682 } else {
1683 // commute and try again
1684 l = cmp1->in(2);
1685 r = cmp1->in(1);
1686 }
1687 }
1688 }
1689
1690 // Change x u< 1 or x u<= 0 to x == 0
1691 // and x u> 0 or u>= 1 to x != 0
1692 if (cop == Op_CmpU &&
1693 cmp1_op != Op_LoadRange &&
1694 (((_test._test == BoolTest::lt || _test._test == BoolTest::ge) &&
1695 cmp2->find_int_con(-1) == 1) ||
1696 ((_test._test == BoolTest::le || _test._test == BoolTest::gt) &&
1697 cmp2->find_int_con(-1) == 0))) {
1698 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1699 return new BoolNode(ncmp, _test.is_less() ? BoolTest::eq : BoolTest::ne);
1700 }
1701
1702 // Change (arraylength <= 0) or (arraylength == 0)
1703 // into (arraylength u<= 0)
1704 // Also change (arraylength != 0) into (arraylength u> 0)
1705 // The latter version matches the code pattern generated for
1706 // array range checks, which will more likely be optimized later.
1707 if (cop == Op_CmpI &&
1708 cmp1_op == Op_LoadRange &&
1709 cmp2->find_int_con(-1) == 0) {
1710 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) {
1711 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1712 return new BoolNode(ncmp, BoolTest::le);
1713 } else if (_test._test == BoolTest::ne) {
1714 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1715 return new BoolNode(ncmp, BoolTest::gt);
1716 }
1717 }
1718
1719 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1720 // This is a standard idiom for branching on a boolean value.
1721 Node *c2b = cmp1;
1722 if( cmp2_type == TypeInt::ZERO &&
1723 cmp1_op == Op_Conv2B &&
1724 (_test._test == BoolTest::eq ||
1725 _test._test == BoolTest::ne) ) {
1726 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1727 ? (Node*)new CmpINode(c2b->in(1),cmp2)
1728 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1729 );
1730 return new BoolNode( ncmp, _test._test );
1731 }
1732
1733 // Comparing a SubI against a zero is equal to comparing the SubI
1734 // arguments directly. This only works for eq and ne comparisons
1735 // due to possible integer overflow.
1736 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1737 (cop == Op_CmpI) &&
1738 (cmp1_op == Op_SubI) &&
1739 ( cmp2_type == TypeInt::ZERO ) ) {
1740 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2)));
1741 return new BoolNode( ncmp, _test._test );
1742 }
1743
1744 // Same as above but with and AddI of a constant
1745 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1746 cop == Op_CmpI &&
1747 cmp1_op == Op_AddI &&
1748 cmp1->in(2) != NULL &&
1749 phase->type(cmp1->in(2))->isa_int() &&
1750 phase->type(cmp1->in(2))->is_int()->is_con() &&
1751 cmp2_type == TypeInt::ZERO &&
1752 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape
1753 ) {
1754 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int();
1755 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi)));
1756 return new BoolNode( ncmp, _test._test );
1757 }
1758
1759 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)"
1760 // since zero check of conditional negation of an integer is equal to
1761 // zero check of the integer directly.
1762 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1763 (cop == Op_CmpI) &&
1764 (cmp2_type == TypeInt::ZERO) &&
1765 (cmp1_op == Op_Phi)) {
1766 // There should be a diamond phi with true path at index 1 or 2
1767 PhiNode *phi = cmp1->as_Phi();
1768 int idx_true = phi->is_diamond_phi();
1769 if (idx_true != 0) {
1770 // True input is in(idx_true) while false input is in(3 - idx_true)
1771 Node *tin = phi->in(idx_true);
1772 Node *fin = phi->in(3 - idx_true);
1773 if ((tin->Opcode() == Op_SubI) &&
1774 (phase->type(tin->in(1)) == TypeInt::ZERO) &&
1775 (tin->in(2) == fin)) {
1776 // Found conditional negation at true path, create a new CmpINode without that
1777 Node *ncmp = phase->transform(new CmpINode(fin, cmp2));
1778 return new BoolNode(ncmp, _test._test);
1779 }
1780 if ((fin->Opcode() == Op_SubI) &&
1781 (phase->type(fin->in(1)) == TypeInt::ZERO) &&
1782 (fin->in(2) == tin)) {
1783 // Found conditional negation at false path, create a new CmpINode without that
1784 Node *ncmp = phase->transform(new CmpINode(tin, cmp2));
1785 return new BoolNode(ncmp, _test._test);
1786 }
1787 }
1788 }
1789
1790 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the
1791 // most general case because negating 0x80000000 does nothing. Needed for
1792 // the CmpF3/SubI/CmpI idiom.
1793 if( cop == Op_CmpI &&
1794 cmp1_op == Op_SubI &&
1795 cmp2_type == TypeInt::ZERO &&
1796 phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1797 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1798 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2));
1799 return new BoolNode( ncmp, _test.commute() );
1800 }
1801
1802 // Try to optimize signed integer comparison
1803 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type);
1804
1805 // The transformation below is not valid for either signed or unsigned
1806 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1807 // This transformation can be resurrected when we are able to
1808 // make inferences about the range of values being subtracted from
1809 // (or added to) relative to the wraparound point.
1810 //
1811 // // Remove +/-1's if possible.
1812 // // "X <= Y-1" becomes "X < Y"
1813 // // "X+1 <= Y" becomes "X < Y"
1814 // // "X < Y+1" becomes "X <= Y"
1815 // // "X-1 < Y" becomes "X <= Y"
1816 // // Do not this to compares off of the counted-loop-end. These guys are
1817 // // checking the trip counter and they want to use the post-incremented
1818 // // counter. If they use the PRE-incremented counter, then the counter has
1819 // // to be incremented in a private block on a loop backedge.
1820 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1821 // return NULL;
1822 // #ifndef PRODUCT
1823 // // Do not do this in a wash GVN pass during verification.
1824 // // Gets triggered by too many simple optimizations to be bothered with
1825 // // re-trying it again and again.
1826 // if( !phase->allow_progress() ) return NULL;
1827 // #endif
1828 // // Not valid for unsigned compare because of corner cases in involving zero.
1829 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1830 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1831 // // "0 <=u Y" is always true).
1832 // if( cmp->Opcode() == Op_CmpU ) return NULL;
1833 // int cmp2_op = cmp2->Opcode();
1834 // if( _test._test == BoolTest::le ) {
1835 // if( cmp1_op == Op_AddI &&
1836 // phase->type( cmp1->in(2) ) == TypeInt::ONE )
1837 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1838 // else if( cmp2_op == Op_AddI &&
1839 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1840 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1841 // } else if( _test._test == BoolTest::lt ) {
1842 // if( cmp1_op == Op_AddI &&
1843 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1844 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1845 // else if( cmp2_op == Op_AddI &&
1846 // phase->type( cmp2->in(2) ) == TypeInt::ONE )
1847 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1848 // }
1849 }
1850
1851 //------------------------------Value------------------------------------------
1852 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
1853 // based on local information. If the input is constant, do it.
1854 const Type* BoolNode::Value(PhaseGVN* phase) const {
1855 return _test.cc2logical( phase->type( in(1) ) );
1856 }
1857
1858 #ifndef PRODUCT
1859 //------------------------------dump_spec--------------------------------------
1860 // Dump special per-node info
1861 void BoolNode::dump_spec(outputStream *st) const {
1862 st->print("[");
1863 _test.dump_on(st);
1864 st->print("]");
1865 }
1866 #endif
1867
1868 //----------------------is_counted_loop_exit_test------------------------------
1869 // Returns true if node is used by a counted loop node.
1870 bool BoolNode::is_counted_loop_exit_test() {
1871 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
1872 Node* use = fast_out(i);
1873 if (use->is_CountedLoopEnd()) {
1874 return true;
1875 }
1876 }
1877 return false;
1878 }
1879
1880 //=============================================================================
1881 //------------------------------Value------------------------------------------
1882 const Type* AbsNode::Value(PhaseGVN* phase) const {
1883 const Type* t1 = phase->type(in(1));
1884 if (t1 == Type::TOP) return Type::TOP;
1885
1886 switch (t1->base()) {
1887 case Type::Int: {
1888 const TypeInt* ti = t1->is_int();
1889 if (ti->is_con()) {
1890 return TypeInt::make(uabs(ti->get_con()));
1891 }
1892 break;
1893 }
1894 case Type::Long: {
1895 const TypeLong* tl = t1->is_long();
1896 if (tl->is_con()) {
1897 return TypeLong::make(uabs(tl->get_con()));
1898 }
1899 break;
1900 }
1901 case Type::FloatCon:
1902 return TypeF::make(abs(t1->getf()));
1903 case Type::DoubleCon:
1904 return TypeD::make(abs(t1->getd()));
1905 default:
1906 break;
1907 }
1908
1909 return bottom_type();
1910 }
1911
1912 //------------------------------Identity----------------------------------------
1913 Node* AbsNode::Identity(PhaseGVN* phase) {
1914 Node* in1 = in(1);
1915 // No need to do abs for non-negative values
1916 if (phase->type(in1)->higher_equal(TypeInt::POS) ||
1917 phase->type(in1)->higher_equal(TypeLong::POS)) {
1918 return in1;
1919 }
1920 // Convert "abs(abs(x))" into "abs(x)"
1921 if (in1->Opcode() == Opcode()) {
1922 return in1;
1923 }
1924 return this;
1925 }
1926
1927 //------------------------------Ideal------------------------------------------
1928 Node* AbsNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1929 Node* in1 = in(1);
1930 // Convert "abs(0-x)" into "abs(x)"
1931 if (in1->is_Sub() && phase->type(in1->in(1))->is_zero_type()) {
1932 set_req_X(1, in1->in(2), phase);
1933 return this;
1934 }
1935 return NULL;
1936 }
1937
1938 //=============================================================================
1939 //------------------------------Value------------------------------------------
1940 // Compute sqrt
1941 const Type* SqrtDNode::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::DoubleCon ) return Type::DOUBLE;
1945 double d = t1->getd();
1946 if( d < 0.0 ) return Type::DOUBLE;
1947 return TypeD::make( sqrt( d ) );
1948 }
1949
1950 const Type* SqrtFNode::Value(PhaseGVN* phase) const {
1951 const Type *t1 = phase->type( in(1) );
1952 if( t1 == Type::TOP ) return Type::TOP;
1953 if( t1->base() != Type::FloatCon ) return Type::FLOAT;
1954 float f = t1->getf();
1955 if( f < 0.0f ) return Type::FLOAT;
1956 return TypeF::make( (float)sqrt( (double)f ) );
1957 }
1958
1959 const Type* ReverseINode::Value(PhaseGVN* phase) const {
1960 const Type *t1 = phase->type( in(1) );
1961 if (t1 == Type::TOP) {
1962 return Type::TOP;
1963 }
1964 const TypeInt* t1int = t1->isa_int();
1965 if (t1int && t1int->is_con()) {
1966 jint res = reverse_bits(t1int->get_con());
1967 return TypeInt::make(res);
1968 }
1969 return bottom_type();
1970 }
1971
1972 const Type* ReverseLNode::Value(PhaseGVN* phase) const {
1973 const Type *t1 = phase->type( in(1) );
1974 if (t1 == Type::TOP) {
1975 return Type::TOP;
1976 }
1977 const TypeLong* t1long = t1->isa_long();
1978 if (t1long && t1long->is_con()) {
1979 jlong res = reverse_bits(t1long->get_con());
1980 return TypeLong::make(res);
1981 }
1982 return bottom_type();
1983 }
1984
1985 Node* ReverseINode::Identity(PhaseGVN* phase) {
1986 if (in(1)->Opcode() == Op_ReverseI) {
1987 return in(1)->in(1);
1988 }
1989 return this;
1990 }
1991
1992 Node* ReverseLNode::Identity(PhaseGVN* phase) {
1993 if (in(1)->Opcode() == Op_ReverseL) {
1994 return in(1)->in(1);
1995 }
1996 return this;
1997 }