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