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
43 // Portions of code courtesy of Clifford Click
44
45 // Optimization - Graph Style
46
47 #include "math.h"
48
49 //=============================================================================
50 //------------------------------Identity---------------------------------------
51 // If right input is a constant 0, return the left input.
52 Node* SubNode::Identity(PhaseGVN* phase) {
53 assert(in(1) != this, "Must already have called Value");
54 assert(in(2) != this, "Must already have called Value");
55
56 // Remove double negation
57 const Type *zero = add_id();
58 if( phase->type( in(1) )->higher_equal( zero ) &&
59 in(2)->Opcode() == Opcode() &&
60 phase->type( in(2)->in(1) )->higher_equal( zero ) ) {
61 return in(2)->in(2);
62 }
63
64 // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y
65 if (in(1)->Opcode() == Op_AddI || in(1)->Opcode() == Op_AddL) {
66 if (in(1)->in(2) == in(2)) {
67 return in(1)->in(1);
68 }
69 if (in(1)->in(1) == in(2)) {
70 return in(1)->in(2);
71 }
72
73 // Also catch: "(X + Opaque2(Y)) - Y". In this case, 'Y' is a loop-varying
74 // trip counter and X is likely to be loop-invariant (that's how O2 Nodes
75 // are originally used, although the optimizer sometimes jiggers things).
76 // This folding through an O2 removes a loop-exit use of a loop-varying
77 // value and generally lowers register pressure in and around the loop.
78 if (in(1)->in(2)->Opcode() == Op_Opaque2 && in(1)->in(2)->in(1) == in(2)) {
79 return in(1)->in(1);
80 }
81 }
82
83 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this;
84 }
85
86 //------------------------------Value------------------------------------------
87 // A subtract node differences it's two inputs.
88 const Type* SubNode::Value_common(PhaseTransform *phase) const {
89 const Node* in1 = in(1);
90 const Node* in2 = in(2);
91 // Either input is TOP ==> the result is TOP
92 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
93 if( t1 == Type::TOP ) return Type::TOP;
94 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
95 if( t2 == Type::TOP ) return Type::TOP;
96
97 // Not correct for SubFnode and AddFNode (must check for infinity)
98 // Equal? Subtract is zero
99 if (in1->eqv_uncast(in2)) return add_id();
100
101 // Either input is BOTTOM ==> the result is the local BOTTOM
102 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM )
103 return bottom_type();
104
105 return NULL;
106 }
107
108 const Type* SubNode::Value(PhaseGVN* phase) const {
109 const Type* t = Value_common(phase);
110 if (t != NULL) {
111 return t;
112 }
113 const Type* t1 = phase->type(in(1));
114 const Type* t2 = phase->type(in(2));
115 return sub(t1,t2); // Local flavor of type subtraction
116
117 }
118
119 SubNode* SubNode::make(Node* in1, Node* in2, BasicType bt) {
120 switch (bt) {
121 case T_INT:
122 return new SubINode(in1, in2);
123 case T_LONG:
124 return new SubLNode(in1, in2);
125 default:
126 fatal("Not implemented for %s", type2name(bt));
127 }
128 return NULL;
129 }
130
131 //=============================================================================
132 //------------------------------Helper function--------------------------------
133
134 static bool is_cloop_increment(Node* inc) {
135 precond(inc->Opcode() == Op_AddI || inc->Opcode() == Op_AddL);
136
137 if (!inc->in(1)->is_Phi()) {
138 return false;
139 }
140 const PhiNode* phi = inc->in(1)->as_Phi();
141
142 if (!phi->region()->is_CountedLoop()) {
143 return false;
144 }
145
146 return inc == phi->region()->as_CountedLoop()->incr();
147 }
148
149 // Given the expression '(x + C) - v', or
150 // 'v - (x + C)', we examine nodes '+' and 'v':
151 //
152 // 1. Do not convert if '+' is a counted-loop increment, because the '-' is
153 // loop invariant and converting extends the live-range of 'x' to overlap
154 // with the '+', forcing another register to be used in the loop.
155 //
156 // 2. Do not convert if 'v' is a counted-loop induction variable, because
157 // 'x' might be invariant.
158 //
159 static bool ok_to_convert(Node* inc, Node* var) {
160 return !(is_cloop_increment(inc) || var->is_cloop_ind_var());
161 }
162
163 //------------------------------Ideal------------------------------------------
164 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){
165 Node *in1 = in(1);
166 Node *in2 = in(2);
167 uint op1 = in1->Opcode();
168 uint op2 = in2->Opcode();
169
170 #ifdef ASSERT
171 // Check for dead loop
172 if ((in1 == this) || (in2 == this) ||
173 ((op1 == Op_AddI || op1 == Op_SubI) &&
174 ((in1->in(1) == this) || (in1->in(2) == this) ||
175 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
176 assert(false, "dead loop in SubINode::Ideal");
177 }
178 #endif
179
180 const Type *t2 = phase->type( in2 );
181 if( t2 == Type::TOP ) return NULL;
182 // Convert "x-c0" into "x+ -c0".
183 if( t2->base() == Type::Int ){ // Might be bottom or top...
184 const TypeInt *i = t2->is_int();
185 if( i->is_con() )
186 return new AddINode(in1, phase->intcon(-i->get_con()));
187 }
188
189 // Convert "(x+c0) - y" into (x-y) + c0"
190 // Do not collapse (x+c0)-y if "+" is a loop increment or
191 // if "y" is a loop induction variable.
192 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) {
193 const Type *tadd = phase->type( in1->in(2) );
194 if( tadd->singleton() && tadd != Type::TOP ) {
195 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 ));
196 return new AddINode( sub2, in1->in(2) );
197 }
198 }
199
200 // Convert "x - (y+c0)" into "(x-y) - c0" AND
201 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
202 // Need the same check as in above optimization but reversed.
203 if (op2 == Op_AddI
204 && ok_to_convert(in2, in1)
205 && in2->in(2)->Opcode() == Op_ConI) {
206 jint c0 = phase->type(in2->in(2))->isa_int()->get_con();
207 Node* in21 = in2->in(1);
208 if (in1->Opcode() == Op_ConI) {
209 // Match c1
210 jint c1 = phase->type(in1)->isa_int()->get_con();
211 Node* sub2 = phase->intcon(java_subtract(c1, c0));
212 return new SubINode(sub2, in21);
213 } else {
214 // Match x
215 Node* sub2 = phase->transform(new SubINode(in1, in21));
216 Node* neg_c0 = phase->intcon(-c0);
217 return new AddINode(sub2, neg_c0);
218 }
219 }
220
221 const Type *t1 = phase->type( in1 );
222 if( t1 == Type::TOP ) return NULL;
223
224 #ifdef ASSERT
225 // Check for dead loop
226 if ((op2 == Op_AddI || op2 == Op_SubI) &&
227 ((in2->in(1) == this) || (in2->in(2) == this) ||
228 (in2->in(1) == in2) || (in2->in(2) == in2))) {
229 assert(false, "dead loop in SubINode::Ideal");
230 }
231 #endif
232
233 // Convert "x - (x+y)" into "-y"
234 if (op2 == Op_AddI && in1 == in2->in(1)) {
235 return new SubINode(phase->intcon(0), in2->in(2));
236 }
237 // Convert "(x-y) - x" into "-y"
238 if (op1 == Op_SubI && in1->in(1) == in2) {
239 return new SubINode(phase->intcon(0), in1->in(2));
240 }
241 // Convert "x - (y+x)" into "-y"
242 if (op2 == Op_AddI && in1 == in2->in(2)) {
243 return new SubINode(phase->intcon(0), in2->in(1));
244 }
245
246 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity().
247 if (t1 == TypeInt::ZERO && op2 == Op_SubI && phase->type(in2->in(1)) != TypeInt::ZERO) {
248 return new SubINode(in2->in(2), in2->in(1));
249 }
250
251 // Convert "0 - (x+con)" into "-con-x"
252 jint con;
253 if( t1 == TypeInt::ZERO && op2 == Op_AddI &&
254 (con = in2->in(2)->find_int_con(0)) != 0 )
255 return new SubINode( phase->intcon(-con), in2->in(1) );
256
257 // Convert "(X+A) - (X+B)" into "A - B"
258 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) )
259 return new SubINode( in1->in(2), in2->in(2) );
260
261 // Convert "(A+X) - (B+X)" into "A - B"
262 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) )
263 return new SubINode( in1->in(1), in2->in(1) );
264
265 // Convert "(A+X) - (X+B)" into "A - B"
266 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) )
267 return new SubINode( in1->in(1), in2->in(2) );
268
269 // Convert "(X+A) - (B+X)" into "A - B"
270 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) )
271 return new SubINode( in1->in(2), in2->in(1) );
272
273 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally
274 // nicer to optimize than subtract.
275 if( op2 == Op_SubI && in2->outcnt() == 1) {
276 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) );
277 return new SubINode( add1, in2->in(1) );
278 }
279
280 // Associative
281 if (op1 == Op_MulI && op2 == Op_MulI) {
282 Node* sub_in1 = NULL;
283 Node* sub_in2 = NULL;
284 Node* mul_in = NULL;
285
286 if (in1->in(1) == in2->in(1)) {
287 // Convert "a*b-a*c into a*(b-c)
288 sub_in1 = in1->in(2);
289 sub_in2 = in2->in(2);
290 mul_in = in1->in(1);
291 } else if (in1->in(2) == in2->in(1)) {
292 // Convert a*b-b*c into b*(a-c)
293 sub_in1 = in1->in(1);
294 sub_in2 = in2->in(2);
295 mul_in = in1->in(2);
296 } else if (in1->in(2) == in2->in(2)) {
297 // Convert a*c-b*c into (a-b)*c
298 sub_in1 = in1->in(1);
299 sub_in2 = in2->in(1);
300 mul_in = in1->in(2);
301 } else if (in1->in(1) == in2->in(2)) {
302 // Convert a*b-c*a into a*(b-c)
303 sub_in1 = in1->in(2);
304 sub_in2 = in2->in(1);
305 mul_in = in1->in(1);
306 }
307
308 if (mul_in != NULL) {
309 Node* sub = phase->transform(new SubINode(sub_in1, sub_in2));
310 return new MulINode(mul_in, sub);
311 }
312 }
313
314 // Convert "0-(A>>31)" into "(A>>>31)"
315 if ( op2 == Op_RShiftI ) {
316 Node *in21 = in2->in(1);
317 Node *in22 = in2->in(2);
318 const TypeInt *zero = phase->type(in1)->isa_int();
319 const TypeInt *t21 = phase->type(in21)->isa_int();
320 const TypeInt *t22 = phase->type(in22)->isa_int();
321 if ( t21 && t22 && zero == TypeInt::ZERO && t22->is_con(31) ) {
322 return new URShiftINode(in21, in22);
323 }
324 }
325
326 return NULL;
327 }
328
329 //------------------------------sub--------------------------------------------
330 // A subtract node differences it's two inputs.
331 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const {
332 const TypeInt *r0 = t1->is_int(); // Handy access
333 const TypeInt *r1 = t2->is_int();
334 int32_t lo = java_subtract(r0->_lo, r1->_hi);
335 int32_t hi = java_subtract(r0->_hi, r1->_lo);
336
337 // We next check for 32-bit overflow.
338 // If that happens, we just assume all integers are possible.
339 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
340 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
341 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
342 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
343 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen));
344 else // Overflow; assume all integers
345 return TypeInt::INT;
346 }
347
348 //=============================================================================
349 //------------------------------Ideal------------------------------------------
350 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
351 Node *in1 = in(1);
352 Node *in2 = in(2);
353 uint op1 = in1->Opcode();
354 uint op2 = in2->Opcode();
355
356 #ifdef ASSERT
357 // Check for dead loop
358 if ((in1 == this) || (in2 == this) ||
359 ((op1 == Op_AddL || op1 == Op_SubL) &&
360 ((in1->in(1) == this) || (in1->in(2) == this) ||
361 (in1->in(1) == in1) || (in1->in(2) == in1)))) {
362 assert(false, "dead loop in SubLNode::Ideal");
363 }
364 #endif
365
366 if( phase->type( in2 ) == Type::TOP ) return NULL;
367 const TypeLong *i = phase->type( in2 )->isa_long();
368 // Convert "x-c0" into "x+ -c0".
369 if( i && // Might be bottom or top...
370 i->is_con() )
371 return new AddLNode(in1, phase->longcon(-i->get_con()));
372
373 // Convert "(x+c0) - y" into (x-y) + c0"
374 // Do not collapse (x+c0)-y if "+" is a loop increment or
375 // if "y" is a loop induction variable.
376 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) {
377 Node *in11 = in1->in(1);
378 const Type *tadd = phase->type( in1->in(2) );
379 if( tadd->singleton() && tadd != Type::TOP ) {
380 Node *sub2 = phase->transform( new SubLNode( in11, in2 ));
381 return new AddLNode( sub2, in1->in(2) );
382 }
383 }
384
385 // Convert "x - (y+c0)" into "(x-y) - c0" AND
386 // Convert "c1 - (y+c0)" into "(c1-c0) - y"
387 // Need the same check as in above optimization but reversed.
388 if (op2 == Op_AddL
389 && ok_to_convert(in2, in1)
390 && in2->in(2)->Opcode() == Op_ConL) {
391 jlong c0 = phase->type(in2->in(2))->isa_long()->get_con();
392 Node* in21 = in2->in(1);
393 if (in1->Opcode() == Op_ConL) {
394 // Match c1
395 jlong c1 = phase->type(in1)->isa_long()->get_con();
396 Node* sub2 = phase->longcon(java_subtract(c1, c0));
397 return new SubLNode(sub2, in21);
398 } else {
399 Node* sub2 = phase->transform(new SubLNode(in1, in21));
400 Node* neg_c0 = phase->longcon(-c0);
401 return new AddLNode(sub2, neg_c0);
402 }
403 }
404
405 const Type *t1 = phase->type( in1 );
406 if( t1 == Type::TOP ) return NULL;
407
408 #ifdef ASSERT
409 // Check for dead loop
410 if ((op2 == Op_AddL || op2 == Op_SubL) &&
411 ((in2->in(1) == this) || (in2->in(2) == this) ||
412 (in2->in(1) == in2) || (in2->in(2) == in2))) {
413 assert(false, "dead loop in SubLNode::Ideal");
414 }
415 #endif
416
417 // Convert "x - (x+y)" into "-y"
418 if (op2 == Op_AddL && in1 == in2->in(1)) {
419 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(2));
420 }
421 // Convert "(x-y) - x" into "-y"
422 if (op1 == Op_SubL && in1->in(1) == in2) {
423 return new SubLNode(phase->makecon(TypeLong::ZERO), in1->in(2));
424 }
425 // Convert "x - (y+x)" into "-y"
426 if (op2 == Op_AddL && in1 == in2->in(2)) {
427 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(1));
428 }
429
430 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity.
431 if (t1 == TypeLong::ZERO && op2 == Op_SubL && phase->type(in2->in(1)) != TypeLong::ZERO) {
432 return new SubLNode(in2->in(2), in2->in(1));
433 }
434
435 // Convert "(X+A) - (X+B)" into "A - B"
436 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) )
437 return new SubLNode( in1->in(2), in2->in(2) );
438
439 // Convert "(A+X) - (B+X)" into "A - B"
440 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) )
441 return new SubLNode( in1->in(1), in2->in(1) );
442
443 // Convert "(A+X) - (X+B)" into "A - B"
444 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(1) )
445 return new SubLNode( in1->in(1), in2->in(2) );
446
447 // Convert "(X+A) - (B+X)" into "A - B"
448 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(2) )
449 return new SubLNode( in1->in(2), in2->in(1) );
450
451 // Convert "A-(B-C)" into (A+C)-B"
452 if( op2 == Op_SubL && in2->outcnt() == 1) {
453 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) );
454 return new SubLNode( add1, in2->in(1) );
455 }
456
457 // Associative
458 if (op1 == Op_MulL && op2 == Op_MulL) {
459 Node* sub_in1 = NULL;
460 Node* sub_in2 = NULL;
461 Node* mul_in = NULL;
462
463 if (in1->in(1) == in2->in(1)) {
464 // Convert "a*b-a*c into a*(b+c)
465 sub_in1 = in1->in(2);
466 sub_in2 = in2->in(2);
467 mul_in = in1->in(1);
468 } else if (in1->in(2) == in2->in(1)) {
469 // Convert a*b-b*c into b*(a-c)
470 sub_in1 = in1->in(1);
471 sub_in2 = in2->in(2);
472 mul_in = in1->in(2);
473 } else if (in1->in(2) == in2->in(2)) {
474 // Convert a*c-b*c into (a-b)*c
475 sub_in1 = in1->in(1);
476 sub_in2 = in2->in(1);
477 mul_in = in1->in(2);
478 } else if (in1->in(1) == in2->in(2)) {
479 // Convert a*b-c*a into a*(b-c)
480 sub_in1 = in1->in(2);
481 sub_in2 = in2->in(1);
482 mul_in = in1->in(1);
483 }
484
485 if (mul_in != NULL) {
486 Node* sub = phase->transform(new SubLNode(sub_in1, sub_in2));
487 return new MulLNode(mul_in, sub);
488 }
489 }
490
491 // Convert "0L-(A>>63)" into "(A>>>63)"
492 if ( op2 == Op_RShiftL ) {
493 Node *in21 = in2->in(1);
494 Node *in22 = in2->in(2);
495 const TypeLong *zero = phase->type(in1)->isa_long();
496 const TypeLong *t21 = phase->type(in21)->isa_long();
497 const TypeInt *t22 = phase->type(in22)->isa_int();
498 if ( t21 && t22 && zero == TypeLong::ZERO && t22->is_con(63) ) {
499 return new URShiftLNode(in21, in22);
500 }
501 }
502
503 return NULL;
504 }
505
506 //------------------------------sub--------------------------------------------
507 // A subtract node differences it's two inputs.
508 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const {
509 const TypeLong *r0 = t1->is_long(); // Handy access
510 const TypeLong *r1 = t2->is_long();
511 jlong lo = java_subtract(r0->_lo, r1->_hi);
512 jlong hi = java_subtract(r0->_hi, r1->_lo);
513
514 // We next check for 32-bit overflow.
515 // If that happens, we just assume all integers are possible.
516 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
517 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
518 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
519 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
520 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen));
521 else // Overflow; assume all integers
522 return TypeLong::LONG;
523 }
524
525 //=============================================================================
526 //------------------------------Value------------------------------------------
527 // A subtract node differences its two inputs.
528 const Type* SubFPNode::Value(PhaseGVN* phase) const {
529 const Node* in1 = in(1);
530 const Node* in2 = in(2);
531 // Either input is TOP ==> the result is TOP
532 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
533 if( t1 == Type::TOP ) return Type::TOP;
534 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
535 if( t2 == Type::TOP ) return Type::TOP;
536
537 // if both operands are infinity of same sign, the result is NaN; do
538 // not replace with zero
539 if (t1->is_finite() && t2->is_finite() && in1 == in2) {
540 return add_id();
541 }
542
543 // Either input is BOTTOM ==> the result is the local BOTTOM
544 const Type *bot = bottom_type();
545 if( (t1 == bot) || (t2 == bot) ||
546 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
547 return bot;
548
549 return sub(t1,t2); // Local flavor of type subtraction
550 }
551
552
553 //=============================================================================
554 //------------------------------Ideal------------------------------------------
555 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
556 const Type *t2 = phase->type( in(2) );
557 // Convert "x-c0" into "x+ -c0".
558 if( t2->base() == Type::FloatCon ) { // Might be bottom or top...
559 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) );
560 }
561
562 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes
563 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0.
564 //if( phase->type(in(1)) == TypeF::ZERO )
565 //return new (phase->C, 2) NegFNode(in(2));
566
567 return NULL;
568 }
569
570 //------------------------------sub--------------------------------------------
571 // A subtract node differences its two inputs.
572 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const {
573 // no folding if one of operands is infinity or NaN, do not do constant folding
574 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) {
575 return TypeF::make( t1->getf() - t2->getf() );
576 }
577 else if( g_isnan(t1->getf()) ) {
578 return t1;
579 }
580 else if( g_isnan(t2->getf()) ) {
581 return t2;
582 }
583 else {
584 return Type::FLOAT;
585 }
586 }
587
588 //=============================================================================
589 //------------------------------Ideal------------------------------------------
590 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){
591 const Type *t2 = phase->type( in(2) );
592 // Convert "x-c0" into "x+ -c0".
593 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top...
594 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) );
595 }
596
597 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes
598 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0.
599 //if( phase->type(in(1)) == TypeD::ZERO )
600 //return new (phase->C, 2) NegDNode(in(2));
601
602 return NULL;
603 }
604
605 //------------------------------sub--------------------------------------------
606 // A subtract node differences its two inputs.
607 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const {
608 // no folding if one of operands is infinity or NaN, do not do constant folding
609 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) {
610 return TypeD::make( t1->getd() - t2->getd() );
611 }
612 else if( g_isnan(t1->getd()) ) {
613 return t1;
614 }
615 else if( g_isnan(t2->getd()) ) {
616 return t2;
617 }
618 else {
619 return Type::DOUBLE;
620 }
621 }
622
623 //=============================================================================
624 //------------------------------Idealize---------------------------------------
625 // Unlike SubNodes, compare must still flatten return value to the
626 // range -1, 0, 1.
627 // And optimizations like those for (X + Y) - X fail if overflow happens.
628 Node* CmpNode::Identity(PhaseGVN* phase) {
629 return this;
630 }
631
632 #ifndef PRODUCT
633 //----------------------------related------------------------------------------
634 // Related nodes of comparison nodes include all data inputs (until hitting a
635 // control boundary) as well as all outputs until and including control nodes
636 // as well as their projections. In compact mode, data inputs till depth 1 and
637 // all outputs till depth 1 are considered.
638 void CmpNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
639 if (compact) {
640 this->collect_nodes(in_rel, 1, false, true);
641 this->collect_nodes(out_rel, -1, false, false);
642 } else {
643 this->collect_nodes_in_all_data(in_rel, false);
644 this->collect_nodes_out_all_ctrl_boundary(out_rel);
645 // Now, find all control nodes in out_rel, and include their projections
646 // and projection targets (if any) in the result.
647 GrowableArray<Node*> proj(Compile::current()->unique());
648 for (GrowableArrayIterator<Node*> it = out_rel->begin(); it != out_rel->end(); ++it) {
649 Node* n = *it;
650 if (n->is_CFG() && !n->is_Proj()) {
651 // Assume projections and projection targets are found at levels 1 and 2.
652 n->collect_nodes(&proj, -2, false, false);
653 for (GrowableArrayIterator<Node*> p = proj.begin(); p != proj.end(); ++p) {
654 out_rel->append_if_missing(*p);
655 }
656 proj.clear();
657 }
658 }
659 }
660 }
661
662 #endif
663
664 CmpNode *CmpNode::make(Node *in1, Node *in2, BasicType bt, bool unsigned_comp) {
665 switch (bt) {
666 case T_INT:
667 if (unsigned_comp) {
668 return new CmpUNode(in1, in2);
669 }
670 return new CmpINode(in1, in2);
671 case T_LONG:
672 if (unsigned_comp) {
673 return new CmpULNode(in1, in2);
674 }
675 return new CmpLNode(in1, in2);
676 default:
677 fatal("Not implemented for %s", type2name(bt));
678 }
679 return NULL;
680 }
681
682 //=============================================================================
683 //------------------------------cmp--------------------------------------------
684 // Simplify a CmpI (compare 2 integers) node, based on local information.
685 // If both inputs are constants, compare them.
686 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const {
687 const TypeInt *r0 = t1->is_int(); // Handy access
688 const TypeInt *r1 = t2->is_int();
689
690 if( r0->_hi < r1->_lo ) // Range is always low?
691 return TypeInt::CC_LT;
692 else if( r0->_lo > r1->_hi ) // Range is always high?
693 return TypeInt::CC_GT;
694
695 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
696 assert(r0->get_con() == r1->get_con(), "must be equal");
697 return TypeInt::CC_EQ; // Equal results.
698 } else if( r0->_hi == r1->_lo ) // Range is never high?
699 return TypeInt::CC_LE;
700 else if( r0->_lo == r1->_hi ) // Range is never low?
701 return TypeInt::CC_GE;
702 return TypeInt::CC; // else use worst case results
703 }
704
705 // Simplify a CmpU (compare 2 integers) node, based on local information.
706 // If both inputs are constants, compare them.
707 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const {
708 assert(!t1->isa_ptr(), "obsolete usage of CmpU");
709
710 // comparing two unsigned ints
711 const TypeInt *r0 = t1->is_int(); // Handy access
712 const TypeInt *r1 = t2->is_int();
713
714 // Current installed version
715 // Compare ranges for non-overlap
716 juint lo0 = r0->_lo;
717 juint hi0 = r0->_hi;
718 juint lo1 = r1->_lo;
719 juint hi1 = r1->_hi;
720
721 // If either one has both negative and positive values,
722 // it therefore contains both 0 and -1, and since [0..-1] is the
723 // full unsigned range, the type must act as an unsigned bottom.
724 bool bot0 = ((jint)(lo0 ^ hi0) < 0);
725 bool bot1 = ((jint)(lo1 ^ hi1) < 0);
726
727 if (bot0 || bot1) {
728 // All unsigned values are LE -1 and GE 0.
729 if (lo0 == 0 && hi0 == 0) {
730 return TypeInt::CC_LE; // 0 <= bot
731 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) {
732 return TypeInt::CC_GE; // -1 >= bot
733 } else if (lo1 == 0 && hi1 == 0) {
734 return TypeInt::CC_GE; // bot >= 0
735 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) {
736 return TypeInt::CC_LE; // bot <= -1
737 }
738 } else {
739 // We can use ranges of the form [lo..hi] if signs are the same.
740 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
741 // results are reversed, '-' > '+' for unsigned compare
742 if (hi0 < lo1) {
743 return TypeInt::CC_LT; // smaller
744 } else if (lo0 > hi1) {
745 return TypeInt::CC_GT; // greater
746 } else if (hi0 == lo1 && lo0 == hi1) {
747 return TypeInt::CC_EQ; // Equal results
748 } else if (lo0 >= hi1) {
749 return TypeInt::CC_GE;
750 } else if (hi0 <= lo1) {
751 // Check for special case in Hashtable::get. (See below.)
752 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
753 return TypeInt::CC_LT;
754 return TypeInt::CC_LE;
755 }
756 }
757 // Check for special case in Hashtable::get - the hash index is
758 // mod'ed to the table size so the following range check is useless.
759 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have
760 // to be positive.
761 // (This is a gross hack, since the sub method never
762 // looks at the structure of the node in any other case.)
763 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
764 return TypeInt::CC_LT;
765 return TypeInt::CC; // else use worst case results
766 }
767
768 const Type* CmpUNode::Value(PhaseGVN* phase) const {
769 const Type* t = SubNode::Value_common(phase);
770 if (t != NULL) {
771 return t;
772 }
773 const Node* in1 = in(1);
774 const Node* in2 = in(2);
775 const Type* t1 = phase->type(in1);
776 const Type* t2 = phase->type(in2);
777 assert(t1->isa_int(), "CmpU has only Int type inputs");
778 if (t2 == TypeInt::INT) { // Compare to bottom?
779 return bottom_type();
780 }
781 uint in1_op = in1->Opcode();
782 if (in1_op == Op_AddI || in1_op == Op_SubI) {
783 // The problem rise when result of AddI(SubI) may overflow
784 // signed integer value. Let say the input type is
785 // [256, maxint] then +128 will create 2 ranges due to
786 // overflow: [minint, minint+127] and [384, maxint].
787 // But C2 type system keep only 1 type range and as result
788 // it use general [minint, maxint] for this case which we
789 // can't optimize.
790 //
791 // Make 2 separate type ranges based on types of AddI(SubI) inputs
792 // and compare results of their compare. If results are the same
793 // CmpU node can be optimized.
794 const Node* in11 = in1->in(1);
795 const Node* in12 = in1->in(2);
796 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11);
797 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12);
798 // Skip cases when input types are top or bottom.
799 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) &&
800 (t12 != Type::TOP) && (t12 != TypeInt::INT)) {
801 const TypeInt *r0 = t11->is_int();
802 const TypeInt *r1 = t12->is_int();
803 jlong lo_r0 = r0->_lo;
804 jlong hi_r0 = r0->_hi;
805 jlong lo_r1 = r1->_lo;
806 jlong hi_r1 = r1->_hi;
807 if (in1_op == Op_SubI) {
808 jlong tmp = hi_r1;
809 hi_r1 = -lo_r1;
810 lo_r1 = -tmp;
811 // Note, for substructing [minint,x] type range
812 // long arithmetic provides correct overflow answer.
813 // The confusion come from the fact that in 32-bit
814 // -minint == minint but in 64-bit -minint == maxint+1.
815 }
816 jlong lo_long = lo_r0 + lo_r1;
817 jlong hi_long = hi_r0 + hi_r1;
818 int lo_tr1 = min_jint;
819 int hi_tr1 = (int)hi_long;
820 int lo_tr2 = (int)lo_long;
821 int hi_tr2 = max_jint;
822 bool underflow = lo_long != (jlong)lo_tr2;
823 bool overflow = hi_long != (jlong)hi_tr1;
824 // Use sub(t1, t2) when there is no overflow (one type range)
825 // or when both overflow and underflow (too complex).
826 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) {
827 // Overflow only on one boundary, compare 2 separate type ranges.
828 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
829 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w);
830 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w);
831 const Type* cmp1 = sub(tr1, t2);
832 const Type* cmp2 = sub(tr2, t2);
833 if (cmp1 == cmp2) {
834 return cmp1; // Hit!
835 }
836 }
837 }
838 }
839
840 return sub(t1, t2); // Local flavor of type subtraction
841 }
842
843 bool CmpUNode::is_index_range_check() const {
844 // Check for the "(X ModI Y) CmpU Y" shape
845 return (in(1)->Opcode() == Op_ModI &&
846 in(1)->in(2)->eqv_uncast(in(2)));
847 }
848
849 //------------------------------Idealize---------------------------------------
850 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
851 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) {
852 switch (in(1)->Opcode()) {
853 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL
854 return new CmpLNode(in(1)->in(1),in(1)->in(2));
855 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF
856 return new CmpFNode(in(1)->in(1),in(1)->in(2));
857 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD
858 return new CmpDNode(in(1)->in(1),in(1)->in(2));
859 //case Op_SubI:
860 // If (x - y) cannot overflow, then ((x - y) <?> 0)
861 // can be turned into (x <?> y).
862 // This is handled (with more general cases) by Ideal_sub_algebra.
863 }
864 }
865 return NULL; // No change
866 }
867
868 //------------------------------Ideal------------------------------------------
869 Node* CmpLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
870 Node* a = NULL;
871 Node* b = NULL;
872 if (is_double_null_check(phase, a, b) && (phase->type(a)->is_zero_type() || phase->type(b)->is_zero_type())) {
873 // Degraded to a simple null check, use old acmp
874 return new CmpPNode(a, b);
875 }
876 const TypeLong *t2 = phase->type(in(2))->isa_long();
877 if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) {
878 const jlong con = t2->get_con();
879 if (con >= min_jint && con <= max_jint) {
880 return new CmpINode(in(1)->in(1), phase->intcon((jint)con));
881 }
882 }
883 return NULL;
884 }
885
886 // Match double null check emitted by Compile::optimize_acmp()
887 bool CmpLNode::is_double_null_check(PhaseGVN* phase, Node*& a, Node*& b) const {
888 if (in(1)->Opcode() == Op_OrL &&
889 in(1)->in(1)->Opcode() == Op_CastP2X &&
890 in(1)->in(2)->Opcode() == Op_CastP2X &&
891 in(2)->bottom_type()->is_zero_type()) {
892 assert(EnableValhalla, "unexpected double null check");
893 a = in(1)->in(1)->in(1);
894 b = in(1)->in(2)->in(1);
895 return true;
896 }
897 return false;
898 }
899
900 //------------------------------Value------------------------------------------
901 const Type* CmpLNode::Value(PhaseGVN* phase) const {
902 Node* a = NULL;
903 Node* b = NULL;
904 if (is_double_null_check(phase, a, b) && (!phase->type(a)->maybe_null() || !phase->type(b)->maybe_null())) {
905 // One operand is never NULL, emit constant false
906 return TypeInt::CC_GT;
907 }
908 return SubNode::Value(phase);
909 }
910
911 //=============================================================================
912 // Simplify a CmpL (compare 2 longs ) node, based on local information.
913 // If both inputs are constants, compare them.
914 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const {
915 const TypeLong *r0 = t1->is_long(); // Handy access
916 const TypeLong *r1 = t2->is_long();
917
918 if( r0->_hi < r1->_lo ) // Range is always low?
919 return TypeInt::CC_LT;
920 else if( r0->_lo > r1->_hi ) // Range is always high?
921 return TypeInt::CC_GT;
922
923 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
924 assert(r0->get_con() == r1->get_con(), "must be equal");
925 return TypeInt::CC_EQ; // Equal results.
926 } else if( r0->_hi == r1->_lo ) // Range is never high?
927 return TypeInt::CC_LE;
928 else if( r0->_lo == r1->_hi ) // Range is never low?
929 return TypeInt::CC_GE;
930 return TypeInt::CC; // else use worst case results
931 }
932
933
934 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information.
935 // If both inputs are constants, compare them.
936 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const {
937 assert(!t1->isa_ptr(), "obsolete usage of CmpUL");
938
939 // comparing two unsigned longs
940 const TypeLong* r0 = t1->is_long(); // Handy access
941 const TypeLong* r1 = t2->is_long();
942
943 // Current installed version
944 // Compare ranges for non-overlap
945 julong lo0 = r0->_lo;
946 julong hi0 = r0->_hi;
947 julong lo1 = r1->_lo;
948 julong hi1 = r1->_hi;
949
950 // If either one has both negative and positive values,
951 // it therefore contains both 0 and -1, and since [0..-1] is the
952 // full unsigned range, the type must act as an unsigned bottom.
953 bool bot0 = ((jlong)(lo0 ^ hi0) < 0);
954 bool bot1 = ((jlong)(lo1 ^ hi1) < 0);
955
956 if (bot0 || bot1) {
957 // All unsigned values are LE -1 and GE 0.
958 if (lo0 == 0 && hi0 == 0) {
959 return TypeInt::CC_LE; // 0 <= bot
960 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) {
961 return TypeInt::CC_GE; // -1 >= bot
962 } else if (lo1 == 0 && hi1 == 0) {
963 return TypeInt::CC_GE; // bot >= 0
964 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) {
965 return TypeInt::CC_LE; // bot <= -1
966 }
967 } else {
968 // We can use ranges of the form [lo..hi] if signs are the same.
969 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
970 // results are reversed, '-' > '+' for unsigned compare
971 if (hi0 < lo1) {
972 return TypeInt::CC_LT; // smaller
973 } else if (lo0 > hi1) {
974 return TypeInt::CC_GT; // greater
975 } else if (hi0 == lo1 && lo0 == hi1) {
976 return TypeInt::CC_EQ; // Equal results
977 } else if (lo0 >= hi1) {
978 return TypeInt::CC_GE;
979 } else if (hi0 <= lo1) {
980 return TypeInt::CC_LE;
981 }
982 }
983
984 return TypeInt::CC; // else use worst case results
985 }
986
987 //=============================================================================
988 //------------------------------sub--------------------------------------------
989 // Simplify an CmpP (compare 2 pointers) node, based on local information.
990 // If both inputs are constants, compare them.
991 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const {
992 const TypePtr *r0 = t1->is_ptr(); // Handy access
993 const TypePtr *r1 = t2->is_ptr();
994
995 // Undefined inputs makes for an undefined result
996 if( TypePtr::above_centerline(r0->_ptr) ||
997 TypePtr::above_centerline(r1->_ptr) )
998 return Type::TOP;
999
1000 if (r0 == r1 && r0->singleton()) {
1001 // Equal pointer constants (klasses, nulls, etc.)
1002 return TypeInt::CC_EQ;
1003 }
1004
1005 // See if it is 2 unrelated classes.
1006 const TypeOopPtr* oop_p0 = r0->isa_oopptr();
1007 const TypeOopPtr* oop_p1 = r1->isa_oopptr();
1008 bool both_oop_ptr = oop_p0 && oop_p1;
1009
1010 if (both_oop_ptr) {
1011 Node* in1 = in(1)->uncast();
1012 Node* in2 = in(2)->uncast();
1013 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1, NULL);
1014 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2, NULL);
1015 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, NULL)) {
1016 return TypeInt::CC_GT; // different pointers
1017 }
1018 }
1019
1020 const TypeKlassPtr* klass_p0 = r0->isa_klassptr();
1021 const TypeKlassPtr* klass_p1 = r1->isa_klassptr();
1022
1023 if (both_oop_ptr || (klass_p0 && klass_p1)) { // both or neither are klass pointers
1024 ciKlass* klass0 = NULL;
1025 bool xklass0 = false;
1026 ciKlass* klass1 = NULL;
1027 bool xklass1 = false;
1028
1029 if (oop_p0) {
1030 klass0 = oop_p0->klass();
1031 xklass0 = oop_p0->klass_is_exact();
1032 } else {
1033 assert(klass_p0, "must be non-null if oop_p0 is null");
1034 klass0 = klass_p0->klass();
1035 xklass0 = klass_p0->klass_is_exact();
1036 }
1037
1038 if (oop_p1) {
1039 klass1 = oop_p1->klass();
1040 xklass1 = oop_p1->klass_is_exact();
1041 } else {
1042 assert(klass_p1, "must be non-null if oop_p1 is null");
1043 klass1 = klass_p1->klass();
1044 xklass1 = klass_p1->klass_is_exact();
1045 }
1046
1047 if (klass0 && klass1 &&
1048 klass0->is_loaded() && !klass0->is_interface() && // do not trust interfaces
1049 klass1->is_loaded() && !klass1->is_interface() &&
1050 (!klass0->is_obj_array_klass() ||
1051 !klass0->as_obj_array_klass()->base_element_klass()->is_interface()) &&
1052 (!klass1->is_obj_array_klass() ||
1053 !klass1->as_obj_array_klass()->base_element_klass()->is_interface())) {
1054 bool unrelated_classes = false;
1055 // See if neither subclasses the other, or if the class on top
1056 // is precise. In either of these cases, the compare is known
1057 // to fail if at least one of the pointers is provably not null.
1058 if (klass0->equals(klass1)) { // if types are unequal but klasses are equal
1059 // Do nothing; we know nothing for imprecise types
1060 } else if (klass0->is_subtype_of(klass1)) {
1061 // If klass1's type is PRECISE, then classes are unrelated.
1062 unrelated_classes = xklass1;
1063 } else if (klass1->is_subtype_of(klass0)) {
1064 // If klass0's type is PRECISE, then classes are unrelated.
1065 unrelated_classes = xklass0;
1066 } else { // Neither subtypes the other
1067 unrelated_classes = true;
1068 }
1069 if (!unrelated_classes) {
1070 // Handle inline type arrays
1071 if ((r0->flatten_array() && (!r1->can_be_inline_type() || (klass1->is_inlinetype() && !klass1->flatten_array()))) ||
1072 (r1->flatten_array() && (!r0->can_be_inline_type() || (klass0->is_inlinetype() && !klass0->flatten_array())))) {
1073 // One type is flattened in arrays but the other type is not. Must be unrelated.
1074 unrelated_classes = true;
1075 } else if ((r0->is_not_flat() && klass1->is_flat_array_klass()) ||
1076 (r1->is_not_flat() && klass0->is_flat_array_klass())) {
1077 // One type is a non-flattened array and the other type is a flattened array. Must be unrelated.
1078 unrelated_classes = true;
1079 } else if ((r0->is_not_null_free() && klass1->is_array_klass() && klass1->as_array_klass()->is_elem_null_free()) ||
1080 (r1->is_not_null_free() && klass0->is_array_klass() && klass0->as_array_klass()->is_elem_null_free())) {
1081 // One type is a non-null-free array and the other type is a null-free array. Must be unrelated.
1082 unrelated_classes = true;
1083 }
1084 }
1085 if (unrelated_classes) {
1086 // The oops classes are known to be unrelated. If the joined PTRs of
1087 // two oops is not Null and not Bottom, then we are sure that one
1088 // of the two oops is non-null, and the comparison will always fail.
1089 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
1090 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
1091 return TypeInt::CC_GT;
1092 }
1093 }
1094 }
1095 }
1096
1097 // Known constants can be compared exactly
1098 // Null can be distinguished from any NotNull pointers
1099 // Unknown inputs makes an unknown result
1100 if( r0->singleton() ) {
1101 intptr_t bits0 = r0->get_con();
1102 if( r1->singleton() )
1103 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
1104 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1105 } else if( r1->singleton() ) {
1106 intptr_t bits1 = r1->get_con();
1107 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1108 } else
1109 return TypeInt::CC;
1110 }
1111
1112 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) {
1113 // Return the klass node for (indirect load from OopHandle)
1114 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
1115 // or NULL if not matching.
1116 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1117 n = bs->step_over_gc_barrier(n);
1118
1119 if (n->Opcode() != Op_LoadP) return NULL;
1120
1121 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1122 if (!tp || tp->klass() != phase->C->env()->Class_klass()) return NULL;
1123
1124 Node* adr = n->in(MemNode::Address);
1125 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier.
1126 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return NULL;
1127 adr = adr->in(MemNode::Address);
1128
1129 intptr_t off = 0;
1130 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off);
1131 if (k == NULL) return NULL;
1132 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr();
1133 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return NULL;
1134
1135 // We've found the klass node of a Java mirror load.
1136 return k;
1137 }
1138
1139 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) {
1140 // for ConP(Foo.class) return ConP(Foo.klass)
1141 // otherwise return NULL
1142 if (!n->is_Con()) return NULL;
1143
1144 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1145 if (!tp) return NULL;
1146
1147 ciType* mirror_type = tp->java_mirror_type();
1148 // TypeInstPtr::java_mirror_type() returns non-NULL for compile-
1149 // time Class constants only.
1150 if (!mirror_type) return NULL;
1151
1152 // x.getClass() == int.class can never be true (for all primitive types)
1153 // Return a ConP(NULL) node for this case.
1154 if (mirror_type->is_classless()) {
1155 return phase->makecon(TypePtr::NULL_PTR);
1156 }
1157
1158 // return the ConP(Foo.klass)
1159 assert(mirror_type->is_klass(), "mirror_type should represent a Klass*");
1160 return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass()));
1161 }
1162
1163 //------------------------------Ideal------------------------------------------
1164 // Normalize comparisons between Java mirror loads to compare the klass instead.
1165 //
1166 // Also check for the case of comparing an unknown klass loaded from the primary
1167 // super-type array vs a known klass with no subtypes. This amounts to
1168 // checking to see an unknown klass subtypes a known klass with no subtypes;
1169 // this only happens on an exact match. We can shorten this test by 1 load.
1170 Node* CmpPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1171 // TODO 8284443 in(1) could be cast?
1172 if (in(1)->is_InlineTypePtr() && phase->type(in(2))->is_zero_type()) {
1173 // Null checking a scalarized but nullable inline type. Check the IsInit
1174 // input instead of the oop input to avoid keeping buffer allocations alive.
1175 return new CmpINode(in(1)->as_InlineTypePtr()->get_is_init(), phase->intcon(0));
1176 }
1177
1178 // Normalize comparisons between Java mirrors into comparisons of the low-
1179 // level klass, where a dependent load could be shortened.
1180 //
1181 // The new pattern has a nice effect of matching the same pattern used in the
1182 // fast path of instanceof/checkcast/Class.isInstance(), which allows
1183 // redundant exact type check be optimized away by GVN.
1184 // For example, in
1185 // if (x.getClass() == Foo.class) {
1186 // Foo foo = (Foo) x;
1187 // // ... use a ...
1188 // }
1189 // a CmpPNode could be shared between if_acmpne and checkcast
1190 {
1191 Node* k1 = isa_java_mirror_load(phase, in(1));
1192 Node* k2 = isa_java_mirror_load(phase, in(2));
1193 Node* conk2 = isa_const_java_mirror(phase, in(2));
1194
1195 if (k1 && (k2 || conk2)) {
1196 Node* lhs = k1;
1197 Node* rhs = (k2 != NULL) ? k2 : conk2;
1198 set_req_X(1, lhs, phase);
1199 set_req_X(2, rhs, phase);
1200 return this;
1201 }
1202 }
1203
1204 // Constant pointer on right?
1205 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
1206 if (t2 == NULL || !t2->klass_is_exact())
1207 return NULL;
1208 // Get the constant klass we are comparing to.
1209 ciKlass* superklass = t2->klass();
1210
1211 // Now check for LoadKlass on left.
1212 Node* ldk1 = in(1);
1213 if (ldk1->is_DecodeNKlass()) {
1214 ldk1 = ldk1->in(1);
1215 if (ldk1->Opcode() != Op_LoadNKlass )
1216 return NULL;
1217 } else if (ldk1->Opcode() != Op_LoadKlass )
1218 return NULL;
1219 // Take apart the address of the LoadKlass:
1220 Node* adr1 = ldk1->in(MemNode::Address);
1221 intptr_t con2 = 0;
1222 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
1223 if (ldk2 == NULL)
1224 return NULL;
1225 if (con2 == oopDesc::klass_offset_in_bytes()) {
1226 // We are inspecting an object's concrete class.
1227 // Short-circuit the check if the query is abstract.
1228 if (superklass->is_interface() ||
1229 superklass->is_abstract()) {
1230 // Make it come out always false:
1231 this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
1232 return this;
1233 }
1234 }
1235
1236 // Check for a LoadKlass from primary supertype array.
1237 // Any nested loadklass from loadklass+con must be from the p.s. array.
1238 if (ldk2->is_DecodeNKlass()) {
1239 // Keep ldk2 as DecodeN since it could be used in CmpP below.
1240 if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
1241 return NULL;
1242 } else if (ldk2->Opcode() != Op_LoadKlass)
1243 return NULL;
1244
1245 // Verify that we understand the situation
1246 if (con2 != (intptr_t) superklass->super_check_offset())
1247 return NULL; // Might be element-klass loading from array klass
1248
1249 // Do not fold the subtype check to an array klass pointer comparison for [V? arrays.
1250 // [QMyValue is a subtype of [LMyValue but the klass for [QMyValue is not equal to
1251 // the klass for [LMyValue. Do not bypass the klass load from the primary supertype array.
1252 if (superklass->is_obj_array_klass() && !superklass->as_array_klass()->is_elem_null_free() &&
1253 superklass->as_array_klass()->element_klass()->is_inlinetype()) {
1254 return NULL;
1255 }
1256
1257 // If 'superklass' has no subklasses and is not an interface, then we are
1258 // assured that the only input which will pass the type check is
1259 // 'superklass' itself.
1260 //
1261 // We could be more liberal here, and allow the optimization on interfaces
1262 // which have a single implementor. This would require us to increase the
1263 // expressiveness of the add_dependency() mechanism.
1264 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now.
1265
1266 // Object arrays must have their base element have no subtypes
1267 while (superklass->is_obj_array_klass()) {
1268 ciType* elem = superklass->as_obj_array_klass()->element_type();
1269 superklass = elem->as_klass();
1270 }
1271 if (superklass->is_instance_klass()) {
1272 ciInstanceKlass* ik = superklass->as_instance_klass();
1273 if (ik->has_subklass() || ik->is_interface()) return NULL;
1274 // Add a dependency if there is a chance that a subclass will be added later.
1275 if (!ik->is_final()) {
1276 phase->C->dependencies()->assert_leaf_type(ik);
1277 }
1278 }
1279
1280 // Bypass the dependent load, and compare directly
1281 this->set_req(1,ldk2);
1282
1283 return this;
1284 }
1285
1286 //=============================================================================
1287 //------------------------------sub--------------------------------------------
1288 // Simplify an CmpN (compare 2 pointers) node, based on local information.
1289 // If both inputs are constants, compare them.
1290 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
1291 ShouldNotReachHere();
1292 return bottom_type();
1293 }
1294
1295 //------------------------------Ideal------------------------------------------
1296 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1297 return NULL;
1298 }
1299
1300 //=============================================================================
1301 //------------------------------Value------------------------------------------
1302 // Simplify an CmpF (compare 2 floats ) node, based on local information.
1303 // If both inputs are constants, compare them.
1304 const Type* CmpFNode::Value(PhaseGVN* phase) const {
1305 const Node* in1 = in(1);
1306 const Node* in2 = in(2);
1307 // Either input is TOP ==> the result is TOP
1308 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1309 if( t1 == Type::TOP ) return Type::TOP;
1310 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1311 if( t2 == Type::TOP ) return Type::TOP;
1312
1313 // Not constants? Don't know squat - even if they are the same
1314 // value! If they are NaN's they compare to LT instead of EQ.
1315 const TypeF *tf1 = t1->isa_float_constant();
1316 const TypeF *tf2 = t2->isa_float_constant();
1317 if( !tf1 || !tf2 ) return TypeInt::CC;
1318
1319 // This implements the Java bytecode fcmpl, so unordered returns -1.
1320 if( tf1->is_nan() || tf2->is_nan() )
1321 return TypeInt::CC_LT;
1322
1323 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
1324 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
1325 assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
1326 return TypeInt::CC_EQ;
1327 }
1328
1329
1330 //=============================================================================
1331 //------------------------------Value------------------------------------------
1332 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
1333 // If both inputs are constants, compare them.
1334 const Type* CmpDNode::Value(PhaseGVN* phase) const {
1335 const Node* in1 = in(1);
1336 const Node* in2 = in(2);
1337 // Either input is TOP ==> the result is TOP
1338 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1339 if( t1 == Type::TOP ) return Type::TOP;
1340 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1341 if( t2 == Type::TOP ) return Type::TOP;
1342
1343 // Not constants? Don't know squat - even if they are the same
1344 // value! If they are NaN's they compare to LT instead of EQ.
1345 const TypeD *td1 = t1->isa_double_constant();
1346 const TypeD *td2 = t2->isa_double_constant();
1347 if( !td1 || !td2 ) return TypeInt::CC;
1348
1349 // This implements the Java bytecode dcmpl, so unordered returns -1.
1350 if( td1->is_nan() || td2->is_nan() )
1351 return TypeInt::CC_LT;
1352
1353 if( td1->_d < td2->_d ) return TypeInt::CC_LT;
1354 if( td1->_d > td2->_d ) return TypeInt::CC_GT;
1355 assert( td1->_d == td2->_d, "do not understand FP behavior" );
1356 return TypeInt::CC_EQ;
1357 }
1358
1359 //------------------------------Ideal------------------------------------------
1360 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
1361 // Check if we can change this to a CmpF and remove a ConvD2F operation.
1362 // Change (CMPD (F2D (float)) (ConD value))
1363 // To (CMPF (float) (ConF value))
1364 // Valid when 'value' does not lose precision as a float.
1365 // Benefits: eliminates conversion, does not require 24-bit mode
1366
1367 // NaNs prevent commuting operands. This transform works regardless of the
1368 // order of ConD and ConvF2D inputs by preserving the original order.
1369 int idx_f2d = 1; // ConvF2D on left side?
1370 if( in(idx_f2d)->Opcode() != Op_ConvF2D )
1371 idx_f2d = 2; // No, swap to check for reversed args
1372 int idx_con = 3-idx_f2d; // Check for the constant on other input
1373
1374 if( ConvertCmpD2CmpF &&
1375 in(idx_f2d)->Opcode() == Op_ConvF2D &&
1376 in(idx_con)->Opcode() == Op_ConD ) {
1377 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
1378 double t2_value_as_double = t2->_d;
1379 float t2_value_as_float = (float)t2_value_as_double;
1380 if( t2_value_as_double == (double)t2_value_as_float ) {
1381 // Test value can be represented as a float
1382 // Eliminate the conversion to double and create new comparison
1383 Node *new_in1 = in(idx_f2d)->in(1);
1384 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
1385 if( idx_f2d != 1 ) { // Must flip args to match original order
1386 Node *tmp = new_in1;
1387 new_in1 = new_in2;
1388 new_in2 = tmp;
1389 }
1390 CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
1391 ? new CmpF3Node( new_in1, new_in2 )
1392 : new CmpFNode ( new_in1, new_in2 ) ;
1393 return new_cmp; // Changed to CmpFNode
1394 }
1395 // Testing value required the precision of a double
1396 }
1397 return NULL; // No change
1398 }
1399
1400 //=============================================================================
1401 //------------------------------Value------------------------------------------
1402 const Type* FlatArrayCheckNode::Value(PhaseGVN* phase) const {
1403 bool all_not_flat = true;
1404 for (uint i = ArrayOrKlass; i < req(); ++i) {
1405 const Type* t = phase->type(in(i));
1406 if (t == Type::TOP) {
1407 return Type::TOP;
1408 }
1409 if (t->is_ptr()->is_flat()) {
1410 // One of the input arrays is flat, check always passes
1411 return TypeInt::CC_EQ;
1412 } else if (!t->is_ptr()->is_not_flat()) {
1413 // One of the input arrays might be flat
1414 all_not_flat = false;
1415 }
1416 }
1417 if (all_not_flat) {
1418 // None of the input arrays can be flat, check always fails
1419 return TypeInt::CC_GT;
1420 }
1421 return TypeInt::CC;
1422 }
1423
1424 //------------------------------Ideal------------------------------------------
1425 Node* FlatArrayCheckNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1426 bool changed = false;
1427 // Remove inputs that are known to be non-flat
1428 for (uint i = ArrayOrKlass; i < req(); ++i) {
1429 const Type* t = phase->type(in(i));
1430 if (t->isa_ptr() && t->is_ptr()->is_not_flat()) {
1431 del_req(i--);
1432 changed = true;
1433 }
1434 }
1435 return changed ? this : NULL;
1436 }
1437
1438 //=============================================================================
1439 //------------------------------cc2logical-------------------------------------
1440 // Convert a condition code type to a logical type
1441 const Type *BoolTest::cc2logical( const Type *CC ) const {
1442 if( CC == Type::TOP ) return Type::TOP;
1443 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
1444 const TypeInt *ti = CC->is_int();
1445 if( ti->is_con() ) { // Only 1 kind of condition codes set?
1446 // Match low order 2 bits
1447 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
1448 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result
1449 return TypeInt::make(tmp); // Boolean result
1450 }
1451
1452 if( CC == TypeInt::CC_GE ) {
1453 if( _test == ge ) return TypeInt::ONE;
1454 if( _test == lt ) return TypeInt::ZERO;
1455 }
1456 if( CC == TypeInt::CC_LE ) {
1457 if( _test == le ) return TypeInt::ONE;
1458 if( _test == gt ) return TypeInt::ZERO;
1459 }
1460
1461 return TypeInt::BOOL;
1462 }
1463
1464 //------------------------------dump_spec-------------------------------------
1465 // Print special per-node info
1466 void BoolTest::dump_on(outputStream *st) const {
1467 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"};
1468 st->print("%s", msg[_test]);
1469 }
1470
1471 // Returns the logical AND of two tests (or 'never' if both tests can never be true).
1472 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'.
1473 BoolTest::mask BoolTest::merge(BoolTest other) const {
1474 const mask res[illegal+1][illegal+1] = {
1475 // eq, gt, of, lt, ne, le, nof, ge, never, illegal
1476 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq
1477 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt
1478 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of
1479 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt
1480 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne
1481 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le
1482 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof
1483 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge
1484 {never, never, never, never, never, never, never, never, never, illegal}, // never
1485 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal
1486 return res[_test][other._test];
1487 }
1488
1489 //=============================================================================
1490 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
1491 uint BoolNode::size_of() const { return sizeof(BoolNode); }
1492
1493 //------------------------------operator==-------------------------------------
1494 bool BoolNode::cmp( const Node &n ) const {
1495 const BoolNode *b = (const BoolNode *)&n; // Cast up
1496 return (_test._test == b->_test._test);
1497 }
1498
1499 //-------------------------------make_predicate--------------------------------
1500 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1501 if (test_value->is_Con()) return test_value;
1502 if (test_value->is_Bool()) return test_value;
1503 if (test_value->is_CMove() &&
1504 test_value->in(CMoveNode::Condition)->is_Bool()) {
1505 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool();
1506 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1507 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1508 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1509 return bol;
1510 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1511 return phase->transform( bol->negate(phase) );
1512 }
1513 // Else fall through. The CMove gets in the way of the test.
1514 // It should be the case that make_predicate(bol->as_int_value()) == bol.
1515 }
1516 Node* cmp = new CmpINode(test_value, phase->intcon(0));
1517 cmp = phase->transform(cmp);
1518 Node* bol = new BoolNode(cmp, BoolTest::ne);
1519 return phase->transform(bol);
1520 }
1521
1522 //--------------------------------as_int_value---------------------------------
1523 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1524 // Inverse to make_predicate. The CMove probably boils down to a Conv2B.
1525 Node* cmov = CMoveNode::make(NULL, this,
1526 phase->intcon(0), phase->intcon(1),
1527 TypeInt::BOOL);
1528 return phase->transform(cmov);
1529 }
1530
1531 //----------------------------------negate-------------------------------------
1532 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1533 return new BoolNode(in(1), _test.negate());
1534 }
1535
1536 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub
1537 // overflows and we can prove that C is not in the two resulting ranges.
1538 // This optimization is similar to the one performed by CmpUNode::Value().
1539 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op,
1540 int cmp1_op, const TypeInt* cmp2_type) {
1541 // Only optimize eq/ne integer comparison of add/sub
1542 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1543 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) {
1544 // Skip cases were inputs of add/sub are not integers or of bottom type
1545 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int();
1546 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int();
1547 if ((r0 != NULL) && (r0 != TypeInt::INT) &&
1548 (r1 != NULL) && (r1 != TypeInt::INT) &&
1549 (cmp2_type != TypeInt::INT)) {
1550 // Compute exact (long) type range of add/sub result
1551 jlong lo_long = r0->_lo;
1552 jlong hi_long = r0->_hi;
1553 if (cmp1_op == Op_AddI) {
1554 lo_long += r1->_lo;
1555 hi_long += r1->_hi;
1556 } else {
1557 lo_long -= r1->_hi;
1558 hi_long -= r1->_lo;
1559 }
1560 // Check for over-/underflow by casting to integer
1561 int lo_int = (int)lo_long;
1562 int hi_int = (int)hi_long;
1563 bool underflow = lo_long != (jlong)lo_int;
1564 bool overflow = hi_long != (jlong)hi_int;
1565 if ((underflow != overflow) && (hi_int < lo_int)) {
1566 // Overflow on one boundary, compute resulting type ranges:
1567 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT]
1568 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
1569 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w);
1570 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w);
1571 // Compare second input of cmp to both type ranges
1572 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type);
1573 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type);
1574 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) {
1575 // The result of the add/sub will never equal cmp2. Replace BoolNode
1576 // by false (0) if it tests for equality and by true (1) otherwise.
1577 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1);
1578 }
1579 }
1580 }
1581 }
1582 return NULL;
1583 }
1584
1585 static bool is_counted_loop_cmp(Node *cmp) {
1586 Node *n = cmp->in(1)->in(1);
1587 return n != NULL &&
1588 n->is_Phi() &&
1589 n->in(0) != NULL &&
1590 n->in(0)->is_CountedLoop() &&
1591 n->in(0)->as_CountedLoop()->phi() == n;
1592 }
1593
1594 //------------------------------Ideal------------------------------------------
1595 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1596 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1597 // This moves the constant to the right. Helps value-numbering.
1598 Node *cmp = in(1);
1599 if( !cmp->is_Sub() ) return NULL;
1600 int cop = cmp->Opcode();
1601 if( cop == Op_FastLock || cop == Op_FastUnlock || cmp->is_SubTypeCheck()) return NULL;
1602 Node *cmp1 = cmp->in(1);
1603 Node *cmp2 = cmp->in(2);
1604 if( !cmp1 ) return NULL;
1605
1606 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) {
1607 return NULL;
1608 }
1609
1610 const int cmp1_op = cmp1->Opcode();
1611 const int cmp2_op = cmp2->Opcode();
1612
1613 // Constant on left?
1614 Node *con = cmp1;
1615 // Move constants to the right of compare's to canonicalize.
1616 // Do not muck with Opaque1 nodes, as this indicates a loop
1617 // guard that cannot change shape.
1618 if( con->is_Con() && !cmp2->is_Con() && cmp2_op != Op_Opaque1 &&
1619 // Because of NaN's, CmpD and CmpF are not commutative
1620 cop != Op_CmpD && cop != Op_CmpF &&
1621 // Protect against swapping inputs to a compare when it is used by a
1622 // counted loop exit, which requires maintaining the loop-limit as in(2)
1623 !is_counted_loop_exit_test() ) {
1624 // Ok, commute the constant to the right of the cmp node.
1625 // Clone the Node, getting a new Node of the same class
1626 cmp = cmp->clone();
1627 // Swap inputs to the clone
1628 cmp->swap_edges(1, 2);
1629 cmp = phase->transform( cmp );
1630 return new BoolNode( cmp, _test.commute() );
1631 }
1632
1633 // Change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1634 if (cop == Op_CmpI &&
1635 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1636 cmp1_op == Op_AndI && cmp2_op == Op_ConI &&
1637 cmp1->in(2)->Opcode() == Op_ConI) {
1638 const TypeInt *t12 = phase->type(cmp2)->isa_int();
1639 const TypeInt *t112 = phase->type(cmp1->in(2))->isa_int();
1640 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1641 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1642 Node *ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1643 return new BoolNode(ncmp, _test.negate());
1644 }
1645 }
1646
1647 // Same for long type: change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1648 if (cop == Op_CmpL &&
1649 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1650 cmp1_op == Op_AndL && cmp2_op == Op_ConL &&
1651 cmp1->in(2)->Opcode() == Op_ConL) {
1652 const TypeLong *t12 = phase->type(cmp2)->isa_long();
1653 const TypeLong *t112 = phase->type(cmp1->in(2))->isa_long();
1654 if (t12 && t12->is_con() && t112 && t112->is_con() &&
1655 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1656 Node *ncmp = phase->transform(new CmpLNode(cmp1, phase->longcon(0)));
1657 return new BoolNode(ncmp, _test.negate());
1658 }
1659 }
1660
1661 // Change "cmp (add X min_jint) (add Y min_jint)" into "cmpu X Y"
1662 // and "cmp (add X min_jint) c" into "cmpu X (c + min_jint)"
1663 if (cop == Op_CmpI &&
1664 cmp1_op == Op_AddI &&
1665 phase->type(cmp1->in(2)) == TypeInt::MIN) {
1666 if (cmp2_op == Op_ConI) {
1667 Node* ncmp2 = phase->intcon(java_add(cmp2->get_int(), min_jint));
1668 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), ncmp2));
1669 return new BoolNode(ncmp, _test._test);
1670 } else if (cmp2_op == Op_AddI &&
1671 phase->type(cmp2->in(2)) == TypeInt::MIN) {
1672 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), cmp2->in(1)));
1673 return new BoolNode(ncmp, _test._test);
1674 }
1675 }
1676
1677 // Change "cmp (add X min_jlong) (add Y min_jlong)" into "cmpu X Y"
1678 // and "cmp (add X min_jlong) c" into "cmpu X (c + min_jlong)"
1679 if (cop == Op_CmpL &&
1680 cmp1_op == Op_AddL &&
1681 phase->type(cmp1->in(2)) == TypeLong::MIN) {
1682 if (cmp2_op == Op_ConL) {
1683 Node* ncmp2 = phase->longcon(java_add(cmp2->get_long(), min_jlong));
1684 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), ncmp2));
1685 return new BoolNode(ncmp, _test._test);
1686 } else if (cmp2_op == Op_AddL &&
1687 phase->type(cmp2->in(2)) == TypeLong::MIN) {
1688 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), cmp2->in(1)));
1689 return new BoolNode(ncmp, _test._test);
1690 }
1691 }
1692
1693 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1694 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the
1695 // test instead.
1696 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1697 if (cmp2_type == NULL) return NULL;
1698 Node* j_xor = cmp1;
1699 if( cmp2_type == TypeInt::ZERO &&
1700 cmp1_op == Op_XorI &&
1701 j_xor->in(1) != j_xor && // An xor of itself is dead
1702 phase->type( j_xor->in(1) ) == TypeInt::BOOL &&
1703 phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1704 (_test._test == BoolTest::eq ||
1705 _test._test == BoolTest::ne) ) {
1706 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2));
1707 return new BoolNode( ncmp, _test.negate() );
1708 }
1709
1710 // Change ((x & m) u<= m) or ((m & x) u<= m) to always true
1711 // Same with ((x & m) u< m+1) and ((m & x) u< m+1)
1712 if (cop == Op_CmpU &&
1713 cmp1_op == Op_AndI) {
1714 Node* bound = NULL;
1715 if (_test._test == BoolTest::le) {
1716 bound = cmp2;
1717 } else if (_test._test == BoolTest::lt &&
1718 cmp2->Opcode() == Op_AddI &&
1719 cmp2->in(2)->find_int_con(0) == 1) {
1720 bound = cmp2->in(1);
1721 }
1722 if (cmp1->in(2) == bound || cmp1->in(1) == bound) {
1723 return ConINode::make(1);
1724 }
1725 }
1726
1727 // Change ((x & (m - 1)) u< m) into (m > 0)
1728 // This is the off-by-one variant of the above
1729 if (cop == Op_CmpU &&
1730 _test._test == BoolTest::lt &&
1731 cmp1_op == Op_AndI) {
1732 Node* l = cmp1->in(1);
1733 Node* r = cmp1->in(2);
1734 for (int repeat = 0; repeat < 2; repeat++) {
1735 bool match = r->Opcode() == Op_AddI && r->in(2)->find_int_con(0) == -1 &&
1736 r->in(1) == cmp2;
1737 if (match) {
1738 // arraylength known to be non-negative, so a (arraylength != 0) is sufficient,
1739 // but to be compatible with the array range check pattern, use (arraylength u> 0)
1740 Node* ncmp = cmp2->Opcode() == Op_LoadRange
1741 ? phase->transform(new CmpUNode(cmp2, phase->intcon(0)))
1742 : phase->transform(new CmpINode(cmp2, phase->intcon(0)));
1743 return new BoolNode(ncmp, BoolTest::gt);
1744 } else {
1745 // commute and try again
1746 l = cmp1->in(2);
1747 r = cmp1->in(1);
1748 }
1749 }
1750 }
1751
1752 // Change x u< 1 or x u<= 0 to x == 0
1753 if (cop == Op_CmpU &&
1754 cmp1_op != Op_LoadRange &&
1755 ((_test._test == BoolTest::lt &&
1756 cmp2->find_int_con(-1) == 1) ||
1757 (_test._test == BoolTest::le &&
1758 cmp2->find_int_con(-1) == 0))) {
1759 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1760 return new BoolNode(ncmp, BoolTest::eq);
1761 }
1762
1763 // Change (arraylength <= 0) or (arraylength == 0)
1764 // into (arraylength u<= 0)
1765 // Also change (arraylength != 0) into (arraylength u> 0)
1766 // The latter version matches the code pattern generated for
1767 // array range checks, which will more likely be optimized later.
1768 if (cop == Op_CmpI &&
1769 cmp1_op == Op_LoadRange &&
1770 cmp2->find_int_con(-1) == 0) {
1771 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) {
1772 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1773 return new BoolNode(ncmp, BoolTest::le);
1774 } else if (_test._test == BoolTest::ne) {
1775 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1776 return new BoolNode(ncmp, BoolTest::gt);
1777 }
1778 }
1779
1780 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1781 // This is a standard idiom for branching on a boolean value.
1782 Node *c2b = cmp1;
1783 if( cmp2_type == TypeInt::ZERO &&
1784 cmp1_op == Op_Conv2B &&
1785 (_test._test == BoolTest::eq ||
1786 _test._test == BoolTest::ne) ) {
1787 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1788 ? (Node*)new CmpINode(c2b->in(1),cmp2)
1789 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1790 );
1791 return new BoolNode( ncmp, _test._test );
1792 }
1793
1794 // Comparing a SubI against a zero is equal to comparing the SubI
1795 // arguments directly. This only works for eq and ne comparisons
1796 // due to possible integer overflow.
1797 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1798 (cop == Op_CmpI) &&
1799 (cmp1_op == Op_SubI) &&
1800 ( cmp2_type == TypeInt::ZERO ) ) {
1801 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2)));
1802 return new BoolNode( ncmp, _test._test );
1803 }
1804
1805 // Same as above but with and AddI of a constant
1806 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1807 cop == Op_CmpI &&
1808 cmp1_op == Op_AddI &&
1809 cmp1->in(2) != NULL &&
1810 phase->type(cmp1->in(2))->isa_int() &&
1811 phase->type(cmp1->in(2))->is_int()->is_con() &&
1812 cmp2_type == TypeInt::ZERO &&
1813 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape
1814 ) {
1815 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int();
1816 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi)));
1817 return new BoolNode( ncmp, _test._test );
1818 }
1819
1820 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)"
1821 // since zero check of conditional negation of an integer is equal to
1822 // zero check of the integer directly.
1823 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1824 (cop == Op_CmpI) &&
1825 (cmp2_type == TypeInt::ZERO) &&
1826 (cmp1_op == Op_Phi)) {
1827 // There should be a diamond phi with true path at index 1 or 2
1828 PhiNode *phi = cmp1->as_Phi();
1829 int idx_true = phi->is_diamond_phi();
1830 if (idx_true != 0) {
1831 // True input is in(idx_true) while false input is in(3 - idx_true)
1832 Node *tin = phi->in(idx_true);
1833 Node *fin = phi->in(3 - idx_true);
1834 if ((tin->Opcode() == Op_SubI) &&
1835 (phase->type(tin->in(1)) == TypeInt::ZERO) &&
1836 (tin->in(2) == fin)) {
1837 // Found conditional negation at true path, create a new CmpINode without that
1838 Node *ncmp = phase->transform(new CmpINode(fin, cmp2));
1839 return new BoolNode(ncmp, _test._test);
1840 }
1841 if ((fin->Opcode() == Op_SubI) &&
1842 (phase->type(fin->in(1)) == TypeInt::ZERO) &&
1843 (fin->in(2) == tin)) {
1844 // Found conditional negation at false path, create a new CmpINode without that
1845 Node *ncmp = phase->transform(new CmpINode(tin, cmp2));
1846 return new BoolNode(ncmp, _test._test);
1847 }
1848 }
1849 }
1850
1851 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the
1852 // most general case because negating 0x80000000 does nothing. Needed for
1853 // the CmpF3/SubI/CmpI idiom.
1854 if( cop == Op_CmpI &&
1855 cmp1_op == Op_SubI &&
1856 cmp2_type == TypeInt::ZERO &&
1857 phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1858 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1859 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2));
1860 return new BoolNode( ncmp, _test.commute() );
1861 }
1862
1863 // Try to optimize signed integer comparison
1864 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type);
1865
1866 // The transformation below is not valid for either signed or unsigned
1867 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1868 // This transformation can be resurrected when we are able to
1869 // make inferences about the range of values being subtracted from
1870 // (or added to) relative to the wraparound point.
1871 //
1872 // // Remove +/-1's if possible.
1873 // // "X <= Y-1" becomes "X < Y"
1874 // // "X+1 <= Y" becomes "X < Y"
1875 // // "X < Y+1" becomes "X <= Y"
1876 // // "X-1 < Y" becomes "X <= Y"
1877 // // Do not this to compares off of the counted-loop-end. These guys are
1878 // // checking the trip counter and they want to use the post-incremented
1879 // // counter. If they use the PRE-incremented counter, then the counter has
1880 // // to be incremented in a private block on a loop backedge.
1881 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1882 // return NULL;
1883 // #ifndef PRODUCT
1884 // // Do not do this in a wash GVN pass during verification.
1885 // // Gets triggered by too many simple optimizations to be bothered with
1886 // // re-trying it again and again.
1887 // if( !phase->allow_progress() ) return NULL;
1888 // #endif
1889 // // Not valid for unsigned compare because of corner cases in involving zero.
1890 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1891 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1892 // // "0 <=u Y" is always true).
1893 // if( cmp->Opcode() == Op_CmpU ) return NULL;
1894 // int cmp2_op = cmp2->Opcode();
1895 // if( _test._test == BoolTest::le ) {
1896 // if( cmp1_op == Op_AddI &&
1897 // phase->type( cmp1->in(2) ) == TypeInt::ONE )
1898 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1899 // else if( cmp2_op == Op_AddI &&
1900 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1901 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1902 // } else if( _test._test == BoolTest::lt ) {
1903 // if( cmp1_op == Op_AddI &&
1904 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1905 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1906 // else if( cmp2_op == Op_AddI &&
1907 // phase->type( cmp2->in(2) ) == TypeInt::ONE )
1908 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1909 // }
1910 }
1911
1912 //------------------------------Value------------------------------------------
1913 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
1914 // based on local information. If the input is constant, do it.
1915 const Type* BoolNode::Value(PhaseGVN* phase) const {
1916 return _test.cc2logical( phase->type( in(1) ) );
1917 }
1918
1919 #ifndef PRODUCT
1920 //------------------------------dump_spec--------------------------------------
1921 // Dump special per-node info
1922 void BoolNode::dump_spec(outputStream *st) const {
1923 st->print("[");
1924 _test.dump_on(st);
1925 st->print("]");
1926 }
1927
1928 //-------------------------------related---------------------------------------
1929 // A BoolNode's related nodes are all of its data inputs, and all of its
1930 // outputs until control nodes are hit, which are included. In compact
1931 // representation, inputs till level 3 and immediate outputs are included.
1932 void BoolNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
1933 if (compact) {
1934 this->collect_nodes(in_rel, 3, false, true);
1935 this->collect_nodes(out_rel, -1, false, false);
1936 } else {
1937 this->collect_nodes_in_all_data(in_rel, false);
1938 this->collect_nodes_out_all_ctrl_boundary(out_rel);
1939 }
1940 }
1941 #endif
1942
1943 //----------------------is_counted_loop_exit_test------------------------------
1944 // Returns true if node is used by a counted loop node.
1945 bool BoolNode::is_counted_loop_exit_test() {
1946 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
1947 Node* use = fast_out(i);
1948 if (use->is_CountedLoopEnd()) {
1949 return true;
1950 }
1951 }
1952 return false;
1953 }
1954
1955 //=============================================================================
1956 //------------------------------Value------------------------------------------
1957 const Type* AbsNode::Value(PhaseGVN* phase) const {
1958 const Type* t1 = phase->type(in(1));
1959 if (t1 == Type::TOP) return Type::TOP;
1960
1961 switch (t1->base()) {
1962 case Type::Int: {
1963 const TypeInt* ti = t1->is_int();
1964 if (ti->is_con()) {
1965 return TypeInt::make(uabs(ti->get_con()));
1966 }
1967 break;
1968 }
1969 case Type::Long: {
1970 const TypeLong* tl = t1->is_long();
1971 if (tl->is_con()) {
1972 return TypeLong::make(uabs(tl->get_con()));
1973 }
1974 break;
1975 }
1976 case Type::FloatCon:
1977 return TypeF::make(abs(t1->getf()));
1978 case Type::DoubleCon:
1979 return TypeD::make(abs(t1->getd()));
1980 default:
1981 break;
1982 }
1983
1984 return bottom_type();
1985 }
1986
1987 //------------------------------Identity----------------------------------------
1988 Node* AbsNode::Identity(PhaseGVN* phase) {
1989 Node* in1 = in(1);
1990 // No need to do abs for non-negative values
1991 if (phase->type(in1)->higher_equal(TypeInt::POS) ||
1992 phase->type(in1)->higher_equal(TypeLong::POS)) {
1993 return in1;
1994 }
1995 // Convert "abs(abs(x))" into "abs(x)"
1996 if (in1->Opcode() == Opcode()) {
1997 return in1;
1998 }
1999 return this;
2000 }
2001
2002 //------------------------------Ideal------------------------------------------
2003 Node* AbsNode::Ideal(PhaseGVN* phase, bool can_reshape) {
2004 Node* in1 = in(1);
2005 // Convert "abs(0-x)" into "abs(x)"
2006 if (in1->is_Sub() && phase->type(in1->in(1))->is_zero_type()) {
2007 set_req_X(1, in1->in(2), phase);
2008 return this;
2009 }
2010 return NULL;
2011 }
2012
2013 //=============================================================================
2014 //------------------------------Value------------------------------------------
2015 // Compute sqrt
2016 const Type* SqrtDNode::Value(PhaseGVN* phase) const {
2017 const Type *t1 = phase->type( in(1) );
2018 if( t1 == Type::TOP ) return Type::TOP;
2019 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
2020 double d = t1->getd();
2021 if( d < 0.0 ) return Type::DOUBLE;
2022 return TypeD::make( sqrt( d ) );
2023 }
2024
2025 const Type* SqrtFNode::Value(PhaseGVN* phase) const {
2026 const Type *t1 = phase->type( in(1) );
2027 if( t1 == Type::TOP ) return Type::TOP;
2028 if( t1->base() != Type::FloatCon ) return Type::FLOAT;
2029 float f = t1->getf();
2030 if( f < 0.0f ) return Type::FLOAT;
2031 return TypeF::make( (float)sqrt( (double)f ) );
2032 }