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