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