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