1 /*
2 * Copyright (c) 1997, 2018, 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.
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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.
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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/macros.hpp"
42 #if INCLUDE_SHENANDOAHGC
43 #include "gc/shenandoah/c2/shenandoahSupport.hpp"
44 #endif
45
46 // Portions of code courtesy of Clifford Click
47
48 // Optimization - Graph Style
49
50 #include "math.h"
51
52 //=============================================================================
53 //------------------------------Identity---------------------------------------
54 // If right input is a constant 0, return the left input.
55 Node* SubNode::Identity(PhaseGVN* phase) {
56 assert(in(1) != this, "Must already have called Value");
57 assert(in(2) != this, "Must already have called Value");
58
59 // Remove double negation
60 const Type *zero = add_id();
61 if( phase->type( in(1) )->higher_equal( zero ) &&
62 in(2)->Opcode() == Opcode() &&
63 phase->type( in(2)->in(1) )->higher_equal( zero ) ) {
64 return in(2)->in(2);
65 }
66
67 // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y
68 if( in(1)->Opcode() == Op_AddI ) {
69 if( phase->eqv(in(1)->in(2),in(2)) )
70 return in(1)->in(1);
71 if (phase->eqv(in(1)->in(1),in(2)))
72 return in(1)->in(2);
73
74 // Also catch: "(X + Opaque2(Y)) - Y". In this case, 'Y' is a loop-varying
75 // trip counter and X is likely to be loop-invariant (that's how O2 Nodes
76 // are originally used, although the optimizer sometimes jiggers things).
77 // This folding through an O2 removes a loop-exit use of a loop-varying
78 // value and generally lowers register pressure in and around the loop.
79 if( in(1)->in(2)->Opcode() == Op_Opaque2 &&
80 phase->eqv(in(1)->in(2)->in(1),in(2)) )
81 return in(1)->in(1);
82 }
83
84 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this;
85 }
86
87 //------------------------------Value------------------------------------------
88 // A subtract node differences it's two inputs.
89 const Type* SubNode::Value_common(PhaseTransform *phase) const {
90 const Node* in1 = in(1);
91 const Node* in2 = in(2);
92 // Either input is TOP ==> the result is TOP
93 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
94 if( t1 == Type::TOP ) return Type::TOP;
95 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
96 if( t2 == Type::TOP ) return Type::TOP;
97
98 // Not correct for SubFnode and AddFNode (must check for infinity)
99 // Equal? Subtract is zero
100 if (in1->eqv_uncast(in2)) return add_id();
101
102 // Either input is BOTTOM ==> the result is the local BOTTOM
103 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM )
104 return bottom_type();
105
106 return NULL;
107 }
108
109 const Type* SubNode::Value(PhaseGVN* phase) const {
110 const Type* t = Value_common(phase);
111 if (t != NULL) {
112 return t;
113 }
114 const Type* t1 = phase->type(in(1));
115 const Type* t2 = phase->type(in(2));
116 return sub(t1,t2); // Local flavor of type subtraction
117
118 }
119
120 //=============================================================================
121
122 //------------------------------Helper function--------------------------------
123 static bool ok_to_convert(Node* inc, Node* iv) {
124 // Do not collapse (x+c0)-y if "+" is a loop increment, because the
125 // "-" is loop invariant and collapsing extends the live-range of "x"
126 // to overlap with the "+", forcing another register to be used in
127 // the loop.
128 // This test will be clearer with '&&' (apply DeMorgan's rule)
129 // but I like the early cutouts that happen here.
130 const PhiNode *phi;
131 if( ( !inc->in(1)->is_Phi() ||
132 !(phi=inc->in(1)->as_Phi()) ||
133 phi->is_copy() ||
134 !phi->region()->is_CountedLoop() ||
135 inc != phi->region()->as_CountedLoop()->incr() )
136 &&
137 // Do not collapse (x+c0)-iv if "iv" is a loop induction variable,
138 // because "x" maybe invariant.
139 ( !iv->is_loop_iv() )
140 ) {
141 return true;
142 } else {
143 return false;
144 }
145 }
146 //------------------------------Ideal------------------------------------------
147 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){
148 Node *in1 = in(1);
149 Node *in2 = in(2);
150 uint op1 = in1->Opcode();
151 uint op2 = in2->Opcode();
152
153 #ifdef ASSERT
154 // Check for dead loop
155 if( phase->eqv( in1, this ) || phase->eqv( in2, this ) ||
156 ( ( op1 == Op_AddI || op1 == Op_SubI ) &&
157 ( phase->eqv( in1->in(1), this ) || phase->eqv( in1->in(2), this ) ||
158 phase->eqv( in1->in(1), in1 ) || phase->eqv( in1->in(2), in1 ) ) ) )
159 assert(false, "dead loop in SubINode::Ideal");
160 #endif
161
162 const Type *t2 = phase->type( in2 );
163 if( t2 == Type::TOP ) return NULL;
164 // Convert "x-c0" into "x+ -c0".
165 if( t2->base() == Type::Int ){ // Might be bottom or top...
166 const TypeInt *i = t2->is_int();
167 if( i->is_con() )
168 return new AddINode(in1, phase->intcon(-i->get_con()));
169 }
170
171 // Convert "(x+c0) - y" into (x-y) + c0"
172 // Do not collapse (x+c0)-y if "+" is a loop increment or
173 // if "y" is a loop induction variable.
174 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) {
175 const Type *tadd = phase->type( in1->in(2) );
176 if( tadd->singleton() && tadd != Type::TOP ) {
177 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 ));
178 return new AddINode( sub2, in1->in(2) );
179 }
180 }
181
182
183 // Convert "x - (y+c0)" into "(x-y) - c0"
184 // Need the same check as in above optimization but reversed.
185 if (op2 == Op_AddI && ok_to_convert(in2, in1)) {
186 Node* in21 = in2->in(1);
187 Node* in22 = in2->in(2);
188 const TypeInt* tcon = phase->type(in22)->isa_int();
189 if (tcon != NULL && tcon->is_con()) {
190 Node* sub2 = phase->transform( new SubINode(in1, in21) );
191 Node* neg_c0 = phase->intcon(- tcon->get_con());
192 return new AddINode(sub2, neg_c0);
193 }
194 }
195
196 const Type *t1 = phase->type( in1 );
197 if( t1 == Type::TOP ) return NULL;
198
199 #ifdef ASSERT
200 // Check for dead loop
201 if( ( op2 == Op_AddI || op2 == Op_SubI ) &&
202 ( phase->eqv( in2->in(1), this ) || phase->eqv( in2->in(2), this ) ||
203 phase->eqv( in2->in(1), in2 ) || phase->eqv( in2->in(2), in2 ) ) )
204 assert(false, "dead loop in SubINode::Ideal");
205 #endif
206
207 // Convert "x - (x+y)" into "-y"
208 if( op2 == Op_AddI &&
209 phase->eqv( in1, in2->in(1) ) )
210 return new SubINode( phase->intcon(0),in2->in(2));
211 // Convert "(x-y) - x" into "-y"
212 if( op1 == Op_SubI &&
213 phase->eqv( in1->in(1), in2 ) )
214 return new SubINode( phase->intcon(0),in1->in(2));
215 // Convert "x - (y+x)" into "-y"
216 if( op2 == Op_AddI &&
217 phase->eqv( in1, in2->in(2) ) )
218 return new SubINode( phase->intcon(0),in2->in(1));
219
220 // Convert "0 - (x-y)" into "y-x"
221 if( t1 == TypeInt::ZERO && op2 == Op_SubI )
222 return new SubINode( in2->in(2), in2->in(1) );
223
224 // Convert "0 - (x+con)" into "-con-x"
225 jint con;
226 if( t1 == TypeInt::ZERO && op2 == Op_AddI &&
227 (con = in2->in(2)->find_int_con(0)) != 0 )
228 return new SubINode( phase->intcon(-con), in2->in(1) );
229
230 // Convert "(X+A) - (X+B)" into "A - B"
231 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) )
232 return new SubINode( in1->in(2), in2->in(2) );
233
234 // Convert "(A+X) - (B+X)" into "A - B"
235 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) )
236 return new SubINode( in1->in(1), in2->in(1) );
237
238 // Convert "(A+X) - (X+B)" into "A - B"
239 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) )
240 return new SubINode( in1->in(1), in2->in(2) );
241
242 // Convert "(X+A) - (B+X)" into "A - B"
243 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) )
244 return new SubINode( in1->in(2), in2->in(1) );
245
246 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally
247 // nicer to optimize than subtract.
248 if( op2 == Op_SubI && in2->outcnt() == 1) {
249 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) );
250 return new SubINode( add1, in2->in(1) );
251 }
252
253 return NULL;
254 }
255
256 //------------------------------sub--------------------------------------------
257 // A subtract node differences it's two inputs.
258 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const {
259 const TypeInt *r0 = t1->is_int(); // Handy access
260 const TypeInt *r1 = t2->is_int();
261 int32_t lo = java_subtract(r0->_lo, r1->_hi);
262 int32_t hi = java_subtract(r0->_hi, r1->_lo);
263
264 // We next check for 32-bit overflow.
265 // If that happens, we just assume all integers are possible.
266 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
267 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
268 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
269 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
270 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen));
271 else // Overflow; assume all integers
272 return TypeInt::INT;
273 }
274
275 //=============================================================================
276 //------------------------------Ideal------------------------------------------
277 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
278 Node *in1 = in(1);
279 Node *in2 = in(2);
280 uint op1 = in1->Opcode();
281 uint op2 = in2->Opcode();
282
283 #ifdef ASSERT
284 // Check for dead loop
285 if( phase->eqv( in1, this ) || phase->eqv( in2, this ) ||
286 ( ( op1 == Op_AddL || op1 == Op_SubL ) &&
287 ( phase->eqv( in1->in(1), this ) || phase->eqv( in1->in(2), this ) ||
288 phase->eqv( in1->in(1), in1 ) || phase->eqv( in1->in(2), in1 ) ) ) )
289 assert(false, "dead loop in SubLNode::Ideal");
290 #endif
291
292 if( phase->type( in2 ) == Type::TOP ) return NULL;
293 const TypeLong *i = phase->type( in2 )->isa_long();
294 // Convert "x-c0" into "x+ -c0".
295 if( i && // Might be bottom or top...
296 i->is_con() )
297 return new AddLNode(in1, phase->longcon(-i->get_con()));
298
299 // Convert "(x+c0) - y" into (x-y) + c0"
300 // Do not collapse (x+c0)-y if "+" is a loop increment or
301 // if "y" is a loop induction variable.
302 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) {
303 Node *in11 = in1->in(1);
304 const Type *tadd = phase->type( in1->in(2) );
305 if( tadd->singleton() && tadd != Type::TOP ) {
306 Node *sub2 = phase->transform( new SubLNode( in11, in2 ));
307 return new AddLNode( sub2, in1->in(2) );
308 }
309 }
310
311 // Convert "x - (y+c0)" into "(x-y) - c0"
312 // Need the same check as in above optimization but reversed.
313 if (op2 == Op_AddL && ok_to_convert(in2, in1)) {
314 Node* in21 = in2->in(1);
315 Node* in22 = in2->in(2);
316 const TypeLong* tcon = phase->type(in22)->isa_long();
317 if (tcon != NULL && tcon->is_con()) {
318 Node* sub2 = phase->transform( new SubLNode(in1, in21) );
319 Node* neg_c0 = phase->longcon(- tcon->get_con());
320 return new AddLNode(sub2, neg_c0);
321 }
322 }
323
324 const Type *t1 = phase->type( in1 );
325 if( t1 == Type::TOP ) return NULL;
326
327 #ifdef ASSERT
328 // Check for dead loop
329 if( ( op2 == Op_AddL || op2 == Op_SubL ) &&
330 ( phase->eqv( in2->in(1), this ) || phase->eqv( in2->in(2), this ) ||
331 phase->eqv( in2->in(1), in2 ) || phase->eqv( in2->in(2), in2 ) ) )
332 assert(false, "dead loop in SubLNode::Ideal");
333 #endif
334
335 // Convert "x - (x+y)" into "-y"
336 if( op2 == Op_AddL &&
337 phase->eqv( in1, in2->in(1) ) )
338 return new SubLNode( phase->makecon(TypeLong::ZERO), in2->in(2));
339 // Convert "x - (y+x)" into "-y"
340 if( op2 == Op_AddL &&
341 phase->eqv( in1, in2->in(2) ) )
342 return new SubLNode( phase->makecon(TypeLong::ZERO),in2->in(1));
343
344 // Convert "0 - (x-y)" into "y-x"
345 if( phase->type( in1 ) == TypeLong::ZERO && op2 == Op_SubL )
346 return new SubLNode( in2->in(2), in2->in(1) );
347
348 // Convert "(X+A) - (X+B)" into "A - B"
349 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) )
350 return new SubLNode( in1->in(2), in2->in(2) );
351
352 // Convert "(A+X) - (B+X)" into "A - B"
353 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) )
354 return new SubLNode( in1->in(1), in2->in(1) );
355
356 // Convert "A-(B-C)" into (A+C)-B"
357 if( op2 == Op_SubL && in2->outcnt() == 1) {
358 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) );
359 return new SubLNode( add1, in2->in(1) );
360 }
361
362 return NULL;
363 }
364
365 //------------------------------sub--------------------------------------------
366 // A subtract node differences it's two inputs.
367 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const {
368 const TypeLong *r0 = t1->is_long(); // Handy access
369 const TypeLong *r1 = t2->is_long();
370 jlong lo = java_subtract(r0->_lo, r1->_hi);
371 jlong hi = java_subtract(r0->_hi, r1->_lo);
372
373 // We next check for 32-bit overflow.
374 // If that happens, we just assume all integers are possible.
375 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
376 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
377 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
378 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
379 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen));
380 else // Overflow; assume all integers
381 return TypeLong::LONG;
382 }
383
384 //=============================================================================
385 //------------------------------Value------------------------------------------
386 // A subtract node differences its two inputs.
387 const Type* SubFPNode::Value(PhaseGVN* phase) const {
388 const Node* in1 = in(1);
389 const Node* in2 = in(2);
390 // Either input is TOP ==> the result is TOP
391 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
392 if( t1 == Type::TOP ) return Type::TOP;
393 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
394 if( t2 == Type::TOP ) return Type::TOP;
395
396 // if both operands are infinity of same sign, the result is NaN; do
397 // not replace with zero
398 if( (t1->is_finite() && t2->is_finite()) ) {
399 if( phase->eqv(in1, in2) ) return add_id();
400 }
401
402 // Either input is BOTTOM ==> the result is the local BOTTOM
403 const Type *bot = bottom_type();
404 if( (t1 == bot) || (t2 == bot) ||
405 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
406 return bot;
407
408 return sub(t1,t2); // Local flavor of type subtraction
409 }
410
411
412 //=============================================================================
413 //------------------------------Ideal------------------------------------------
414 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
415 const Type *t2 = phase->type( in(2) );
416 // Convert "x-c0" into "x+ -c0".
417 if( t2->base() == Type::FloatCon ) { // Might be bottom or top...
418 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) );
419 }
420
421 // Not associative because of boundary conditions (infinity)
422 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
423 // Convert "x - (x+y)" into "-y"
424 if( in(2)->is_Add() &&
425 phase->eqv(in(1),in(2)->in(1) ) )
426 return new SubFNode( phase->makecon(TypeF::ZERO),in(2)->in(2));
427 }
428
429 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes
430 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0.
431 //if( phase->type(in(1)) == TypeF::ZERO )
432 //return new (phase->C, 2) NegFNode(in(2));
433
434 return NULL;
435 }
436
437 //------------------------------sub--------------------------------------------
438 // A subtract node differences its two inputs.
439 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const {
440 // no folding if one of operands is infinity or NaN, do not do constant folding
441 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) {
442 return TypeF::make( t1->getf() - t2->getf() );
443 }
444 else if( g_isnan(t1->getf()) ) {
445 return t1;
446 }
447 else if( g_isnan(t2->getf()) ) {
448 return t2;
449 }
450 else {
451 return Type::FLOAT;
452 }
453 }
454
455 //=============================================================================
456 //------------------------------Ideal------------------------------------------
457 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){
458 const Type *t2 = phase->type( in(2) );
459 // Convert "x-c0" into "x+ -c0".
460 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top...
461 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) );
462 }
463
464 // Not associative because of boundary conditions (infinity)
465 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
466 // Convert "x - (x+y)" into "-y"
467 if( in(2)->is_Add() &&
468 phase->eqv(in(1),in(2)->in(1) ) )
469 return new SubDNode( phase->makecon(TypeD::ZERO),in(2)->in(2));
470 }
471
472 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes
473 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0.
474 //if( phase->type(in(1)) == TypeD::ZERO )
475 //return new (phase->C, 2) NegDNode(in(2));
476
477 return NULL;
478 }
479
480 //------------------------------sub--------------------------------------------
481 // A subtract node differences its two inputs.
482 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const {
483 // no folding if one of operands is infinity or NaN, do not do constant folding
484 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) {
485 return TypeD::make( t1->getd() - t2->getd() );
486 }
487 else if( g_isnan(t1->getd()) ) {
488 return t1;
489 }
490 else if( g_isnan(t2->getd()) ) {
491 return t2;
492 }
493 else {
494 return Type::DOUBLE;
495 }
496 }
497
498 //=============================================================================
499 //------------------------------Idealize---------------------------------------
500 // Unlike SubNodes, compare must still flatten return value to the
501 // range -1, 0, 1.
502 // And optimizations like those for (X + Y) - X fail if overflow happens.
503 Node* CmpNode::Identity(PhaseGVN* phase) {
504 return this;
505 }
506
507 #ifndef PRODUCT
508 //----------------------------related------------------------------------------
509 // Related nodes of comparison nodes include all data inputs (until hitting a
510 // control boundary) as well as all outputs until and including control nodes
511 // as well as their projections. In compact mode, data inputs till depth 1 and
512 // all outputs till depth 1 are considered.
513 void CmpNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
514 if (compact) {
515 this->collect_nodes(in_rel, 1, false, true);
516 this->collect_nodes(out_rel, -1, false, false);
517 } else {
518 this->collect_nodes_in_all_data(in_rel, false);
519 this->collect_nodes_out_all_ctrl_boundary(out_rel);
520 // Now, find all control nodes in out_rel, and include their projections
521 // and projection targets (if any) in the result.
522 GrowableArray<Node*> proj(Compile::current()->unique());
523 for (GrowableArrayIterator<Node*> it = out_rel->begin(); it != out_rel->end(); ++it) {
524 Node* n = *it;
525 if (n->is_CFG() && !n->is_Proj()) {
526 // Assume projections and projection targets are found at levels 1 and 2.
527 n->collect_nodes(&proj, -2, false, false);
528 for (GrowableArrayIterator<Node*> p = proj.begin(); p != proj.end(); ++p) {
529 out_rel->append_if_missing(*p);
530 }
531 proj.clear();
532 }
533 }
534 }
535 }
536 #endif
537
538 //=============================================================================
539 //------------------------------cmp--------------------------------------------
540 // Simplify a CmpI (compare 2 integers) node, based on local information.
541 // If both inputs are constants, compare them.
542 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const {
543 const TypeInt *r0 = t1->is_int(); // Handy access
544 const TypeInt *r1 = t2->is_int();
545
546 if( r0->_hi < r1->_lo ) // Range is always low?
547 return TypeInt::CC_LT;
548 else if( r0->_lo > r1->_hi ) // Range is always high?
549 return TypeInt::CC_GT;
550
551 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
552 assert(r0->get_con() == r1->get_con(), "must be equal");
553 return TypeInt::CC_EQ; // Equal results.
554 } else if( r0->_hi == r1->_lo ) // Range is never high?
555 return TypeInt::CC_LE;
556 else if( r0->_lo == r1->_hi ) // Range is never low?
557 return TypeInt::CC_GE;
558 return TypeInt::CC; // else use worst case results
559 }
560
561 // Simplify a CmpU (compare 2 integers) node, based on local information.
562 // If both inputs are constants, compare them.
563 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const {
564 assert(!t1->isa_ptr(), "obsolete usage of CmpU");
565
566 // comparing two unsigned ints
567 const TypeInt *r0 = t1->is_int(); // Handy access
568 const TypeInt *r1 = t2->is_int();
569
570 // Current installed version
571 // Compare ranges for non-overlap
572 juint lo0 = r0->_lo;
573 juint hi0 = r0->_hi;
574 juint lo1 = r1->_lo;
575 juint hi1 = r1->_hi;
576
577 // If either one has both negative and positive values,
578 // it therefore contains both 0 and -1, and since [0..-1] is the
579 // full unsigned range, the type must act as an unsigned bottom.
580 bool bot0 = ((jint)(lo0 ^ hi0) < 0);
581 bool bot1 = ((jint)(lo1 ^ hi1) < 0);
582
583 if (bot0 || bot1) {
584 // All unsigned values are LE -1 and GE 0.
585 if (lo0 == 0 && hi0 == 0) {
586 return TypeInt::CC_LE; // 0 <= bot
587 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) {
588 return TypeInt::CC_GE; // -1 >= bot
589 } else if (lo1 == 0 && hi1 == 0) {
590 return TypeInt::CC_GE; // bot >= 0
591 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) {
592 return TypeInt::CC_LE; // bot <= -1
593 }
594 } else {
595 // We can use ranges of the form [lo..hi] if signs are the same.
596 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
597 // results are reversed, '-' > '+' for unsigned compare
598 if (hi0 < lo1) {
599 return TypeInt::CC_LT; // smaller
600 } else if (lo0 > hi1) {
601 return TypeInt::CC_GT; // greater
602 } else if (hi0 == lo1 && lo0 == hi1) {
603 return TypeInt::CC_EQ; // Equal results
604 } else if (lo0 >= hi1) {
605 return TypeInt::CC_GE;
606 } else if (hi0 <= lo1) {
607 // Check for special case in Hashtable::get. (See below.)
608 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
609 return TypeInt::CC_LT;
610 return TypeInt::CC_LE;
611 }
612 }
613 // Check for special case in Hashtable::get - the hash index is
614 // mod'ed to the table size so the following range check is useless.
615 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have
616 // to be positive.
617 // (This is a gross hack, since the sub method never
618 // looks at the structure of the node in any other case.)
619 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
620 return TypeInt::CC_LT;
621 return TypeInt::CC; // else use worst case results
622 }
623
624 const Type* CmpUNode::Value(PhaseGVN* phase) const {
625 const Type* t = SubNode::Value_common(phase);
626 if (t != NULL) {
627 return t;
628 }
629 const Node* in1 = in(1);
630 const Node* in2 = in(2);
631 const Type* t1 = phase->type(in1);
632 const Type* t2 = phase->type(in2);
633 assert(t1->isa_int(), "CmpU has only Int type inputs");
634 if (t2 == TypeInt::INT) { // Compare to bottom?
635 return bottom_type();
636 }
637 uint in1_op = in1->Opcode();
638 if (in1_op == Op_AddI || in1_op == Op_SubI) {
639 // The problem rise when result of AddI(SubI) may overflow
640 // signed integer value. Let say the input type is
641 // [256, maxint] then +128 will create 2 ranges due to
642 // overflow: [minint, minint+127] and [384, maxint].
643 // But C2 type system keep only 1 type range and as result
644 // it use general [minint, maxint] for this case which we
645 // can't optimize.
646 //
647 // Make 2 separate type ranges based on types of AddI(SubI) inputs
648 // and compare results of their compare. If results are the same
649 // CmpU node can be optimized.
650 const Node* in11 = in1->in(1);
651 const Node* in12 = in1->in(2);
652 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11);
653 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12);
654 // Skip cases when input types are top or bottom.
655 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) &&
656 (t12 != Type::TOP) && (t12 != TypeInt::INT)) {
657 const TypeInt *r0 = t11->is_int();
658 const TypeInt *r1 = t12->is_int();
659 jlong lo_r0 = r0->_lo;
660 jlong hi_r0 = r0->_hi;
661 jlong lo_r1 = r1->_lo;
662 jlong hi_r1 = r1->_hi;
663 if (in1_op == Op_SubI) {
664 jlong tmp = hi_r1;
665 hi_r1 = -lo_r1;
666 lo_r1 = -tmp;
667 // Note, for substructing [minint,x] type range
668 // long arithmetic provides correct overflow answer.
669 // The confusion come from the fact that in 32-bit
670 // -minint == minint but in 64-bit -minint == maxint+1.
671 }
672 jlong lo_long = lo_r0 + lo_r1;
673 jlong hi_long = hi_r0 + hi_r1;
674 int lo_tr1 = min_jint;
675 int hi_tr1 = (int)hi_long;
676 int lo_tr2 = (int)lo_long;
677 int hi_tr2 = max_jint;
678 bool underflow = lo_long != (jlong)lo_tr2;
679 bool overflow = hi_long != (jlong)hi_tr1;
680 // Use sub(t1, t2) when there is no overflow (one type range)
681 // or when both overflow and underflow (too complex).
682 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) {
683 // Overflow only on one boundary, compare 2 separate type ranges.
684 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
685 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w);
686 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w);
687 const Type* cmp1 = sub(tr1, t2);
688 const Type* cmp2 = sub(tr2, t2);
689 if (cmp1 == cmp2) {
690 return cmp1; // Hit!
691 }
692 }
693 }
694 }
695
696 return sub(t1, t2); // Local flavor of type subtraction
697 }
698
699 bool CmpUNode::is_index_range_check() const {
700 // Check for the "(X ModI Y) CmpU Y" shape
701 return (in(1)->Opcode() == Op_ModI &&
702 in(1)->in(2)->eqv_uncast(in(2)));
703 }
704
705 //------------------------------Idealize---------------------------------------
706 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
707 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) {
708 switch (in(1)->Opcode()) {
709 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL
710 return new CmpLNode(in(1)->in(1),in(1)->in(2));
711 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF
712 return new CmpFNode(in(1)->in(1),in(1)->in(2));
713 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD
714 return new CmpDNode(in(1)->in(1),in(1)->in(2));
715 //case Op_SubI:
716 // If (x - y) cannot overflow, then ((x - y) <?> 0)
717 // can be turned into (x <?> y).
718 // This is handled (with more general cases) by Ideal_sub_algebra.
719 }
720 }
721 return NULL; // No change
722 }
723
724
725 //=============================================================================
726 // Simplify a CmpL (compare 2 longs ) node, based on local information.
727 // If both inputs are constants, compare them.
728 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const {
729 const TypeLong *r0 = t1->is_long(); // Handy access
730 const TypeLong *r1 = t2->is_long();
731
732 if( r0->_hi < r1->_lo ) // Range is always low?
733 return TypeInt::CC_LT;
734 else if( r0->_lo > r1->_hi ) // Range is always high?
735 return TypeInt::CC_GT;
736
737 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
738 assert(r0->get_con() == r1->get_con(), "must be equal");
739 return TypeInt::CC_EQ; // Equal results.
740 } else if( r0->_hi == r1->_lo ) // Range is never high?
741 return TypeInt::CC_LE;
742 else if( r0->_lo == r1->_hi ) // Range is never low?
743 return TypeInt::CC_GE;
744 return TypeInt::CC; // else use worst case results
745 }
746
747
748 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information.
749 // If both inputs are constants, compare them.
750 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const {
751 assert(!t1->isa_ptr(), "obsolete usage of CmpUL");
752
753 // comparing two unsigned longs
754 const TypeLong* r0 = t1->is_long(); // Handy access
755 const TypeLong* r1 = t2->is_long();
756
757 // Current installed version
758 // Compare ranges for non-overlap
759 julong lo0 = r0->_lo;
760 julong hi0 = r0->_hi;
761 julong lo1 = r1->_lo;
762 julong hi1 = r1->_hi;
763
764 // If either one has both negative and positive values,
765 // it therefore contains both 0 and -1, and since [0..-1] is the
766 // full unsigned range, the type must act as an unsigned bottom.
767 bool bot0 = ((jlong)(lo0 ^ hi0) < 0);
768 bool bot1 = ((jlong)(lo1 ^ hi1) < 0);
769
770 if (bot0 || bot1) {
771 // All unsigned values are LE -1 and GE 0.
772 if (lo0 == 0 && hi0 == 0) {
773 return TypeInt::CC_LE; // 0 <= bot
774 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) {
775 return TypeInt::CC_GE; // -1 >= bot
776 } else if (lo1 == 0 && hi1 == 0) {
777 return TypeInt::CC_GE; // bot >= 0
778 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) {
779 return TypeInt::CC_LE; // bot <= -1
780 }
781 } else {
782 // We can use ranges of the form [lo..hi] if signs are the same.
783 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
784 // results are reversed, '-' > '+' for unsigned compare
785 if (hi0 < lo1) {
786 return TypeInt::CC_LT; // smaller
787 } else if (lo0 > hi1) {
788 return TypeInt::CC_GT; // greater
789 } else if (hi0 == lo1 && lo0 == hi1) {
790 return TypeInt::CC_EQ; // Equal results
791 } else if (lo0 >= hi1) {
792 return TypeInt::CC_GE;
793 } else if (hi0 <= lo1) {
794 return TypeInt::CC_LE;
795 }
796 }
797
798 return TypeInt::CC; // else use worst case results
799 }
800
801 //=============================================================================
802 //------------------------------sub--------------------------------------------
803 // Simplify an CmpP (compare 2 pointers) node, based on local information.
804 // If both inputs are constants, compare them.
805 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const {
806 const TypePtr *r0 = t1->is_ptr(); // Handy access
807 const TypePtr *r1 = t2->is_ptr();
808
809 // Undefined inputs makes for an undefined result
810 if( TypePtr::above_centerline(r0->_ptr) ||
811 TypePtr::above_centerline(r1->_ptr) )
812 return Type::TOP;
813
814 if (r0 == r1 && r0->singleton()) {
815 // Equal pointer constants (klasses, nulls, etc.)
816 return TypeInt::CC_EQ;
817 }
818
819 // See if it is 2 unrelated classes.
820 const TypeOopPtr* p0 = r0->isa_oopptr();
821 const TypeOopPtr* p1 = r1->isa_oopptr();
822 if (p0 && p1) {
823 Node* in1 = in(1)->uncast();
824 Node* in2 = in(2)->uncast();
825 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1, NULL);
826 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2, NULL);
827 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, NULL)) {
828 return TypeInt::CC_GT; // different pointers
829 }
830 ciKlass* klass0 = p0->klass();
831 bool xklass0 = p0->klass_is_exact();
832 ciKlass* klass1 = p1->klass();
833 bool xklass1 = p1->klass_is_exact();
834 int kps = (p0->isa_klassptr()?1:0) + (p1->isa_klassptr()?1:0);
835 if (klass0 && klass1 &&
836 kps != 1 && // both or neither are klass pointers
837 klass0->is_loaded() && !klass0->is_interface() && // do not trust interfaces
838 klass1->is_loaded() && !klass1->is_interface() &&
839 (!klass0->is_obj_array_klass() ||
840 !klass0->as_obj_array_klass()->base_element_klass()->is_interface()) &&
841 (!klass1->is_obj_array_klass() ||
842 !klass1->as_obj_array_klass()->base_element_klass()->is_interface())) {
843 bool unrelated_classes = false;
844 // See if neither subclasses the other, or if the class on top
845 // is precise. In either of these cases, the compare is known
846 // to fail if at least one of the pointers is provably not null.
847 if (klass0->equals(klass1)) { // if types are unequal but klasses are equal
848 // Do nothing; we know nothing for imprecise types
849 } else if (klass0->is_subtype_of(klass1)) {
850 // If klass1's type is PRECISE, then classes are unrelated.
851 unrelated_classes = xklass1;
852 } else if (klass1->is_subtype_of(klass0)) {
853 // If klass0's type is PRECISE, then classes are unrelated.
854 unrelated_classes = xklass0;
855 } else { // Neither subtypes the other
856 unrelated_classes = true;
857 }
858 if (unrelated_classes) {
859 // The oops classes are known to be unrelated. If the joined PTRs of
860 // two oops is not Null and not Bottom, then we are sure that one
861 // of the two oops is non-null, and the comparison will always fail.
862 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
863 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
864 return TypeInt::CC_GT;
865 }
866 }
867 }
868 }
869
870 // Known constants can be compared exactly
871 // Null can be distinguished from any NotNull pointers
872 // Unknown inputs makes an unknown result
873 if( r0->singleton() ) {
874 intptr_t bits0 = r0->get_con();
875 if( r1->singleton() )
876 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
877 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
878 } else if( r1->singleton() ) {
879 intptr_t bits1 = r1->get_con();
880 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
881 } else
882 return TypeInt::CC;
883 }
884
885 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) {
886 // Return the klass node for (indirect load from OopHandle)
887 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
888 // or NULL if not matching.
889 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
890 n = bs->step_over_gc_barrier(n);
891
892 if (n->Opcode() != Op_LoadP) return NULL;
893
894 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
895 if (!tp || tp->klass() != phase->C->env()->Class_klass()) return NULL;
896
897 Node* adr = n->in(MemNode::Address);
898 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier.
899 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return NULL;
900 adr = adr->in(MemNode::Address);
901
902 intptr_t off = 0;
903 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off);
904 if (k == NULL) return NULL;
905 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr();
906 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return NULL;
907
908 // We've found the klass node of a Java mirror load.
909 return k;
910 }
911
912 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) {
913 // for ConP(Foo.class) return ConP(Foo.klass)
914 // otherwise return NULL
915 if (!n->is_Con()) return NULL;
916
917 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
918 if (!tp) return NULL;
919
920 ciType* mirror_type = tp->java_mirror_type();
921 // TypeInstPtr::java_mirror_type() returns non-NULL for compile-
922 // time Class constants only.
923 if (!mirror_type) return NULL;
924
925 // x.getClass() == int.class can never be true (for all primitive types)
926 // Return a ConP(NULL) node for this case.
927 if (mirror_type->is_classless()) {
928 return phase->makecon(TypePtr::NULL_PTR);
929 }
930
931 // return the ConP(Foo.klass)
932 assert(mirror_type->is_klass(), "mirror_type should represent a Klass*");
933 return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass()));
934 }
935
936 //------------------------------Ideal------------------------------------------
937 // Normalize comparisons between Java mirror loads to compare the klass instead.
938 //
939 // Also check for the case of comparing an unknown klass loaded from the primary
940 // super-type array vs a known klass with no subtypes. This amounts to
941 // checking to see an unknown klass subtypes a known klass with no subtypes;
942 // this only happens on an exact match. We can shorten this test by 1 load.
943 Node *CmpPNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
944 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
945 #if INCLUDE_SHENANDOAHGC
946 if (UseShenandoahGC) {
947 Node* in1 = in(1);
948 Node* in2 = in(2);
949 if (in1->bottom_type() == TypePtr::NULL_PTR) {
950 in2 = bs->step_over_gc_barrier(in2);
951 }
952 if (in2->bottom_type() == TypePtr::NULL_PTR) {
953 in1 = bs->step_over_gc_barrier(in1);
954 }
955 PhaseIterGVN* igvn = phase->is_IterGVN();
956 if (in1 != in(1)) {
957 if (igvn != NULL) {
958 set_req_X(1, in1, igvn);
959 } else {
960 set_req(1, in1);
961 }
962 assert(in2 == in(2), "only one change");
963 return this;
964 }
965 if (in2 != in(2)) {
966 if (igvn != NULL) {
967 set_req_X(2, in2, igvn);
968 } else {
969 set_req(2, in2);
970 }
971 return this;
972 }
973 }
974 #endif
975
976 // Normalize comparisons between Java mirrors into comparisons of the low-
977 // level klass, where a dependent load could be shortened.
978 //
979 // The new pattern has a nice effect of matching the same pattern used in the
980 // fast path of instanceof/checkcast/Class.isInstance(), which allows
981 // redundant exact type check be optimized away by GVN.
982 // For example, in
983 // if (x.getClass() == Foo.class) {
984 // Foo foo = (Foo) x;
985 // // ... use a ...
986 // }
987 // a CmpPNode could be shared between if_acmpne and checkcast
988 {
989 Node* k1 = isa_java_mirror_load(phase, in(1));
990 Node* k2 = isa_java_mirror_load(phase, in(2));
991 Node* conk2 = isa_const_java_mirror(phase, in(2));
992
993 if (k1 && (k2 || conk2)) {
994 Node* lhs = k1;
995 Node* rhs = (k2 != NULL) ? k2 : conk2;
996 PhaseIterGVN* igvn = phase->is_IterGVN();
997 if (igvn != NULL) {
998 set_req_X(1, lhs, igvn);
999 set_req_X(2, rhs, igvn);
1000 } else {
1001 set_req(1, lhs);
1002 set_req(2, rhs);
1003 }
1004 return this;
1005 }
1006 }
1007
1008 // Constant pointer on right?
1009 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
1010 if (t2 == NULL || !t2->klass_is_exact())
1011 return NULL;
1012 // Get the constant klass we are comparing to.
1013 ciKlass* superklass = t2->klass();
1014
1015 // Now check for LoadKlass on left.
1016 Node* ldk1 = in(1);
1017 if (ldk1->is_DecodeNKlass()) {
1018 ldk1 = ldk1->in(1);
1019 if (ldk1->Opcode() != Op_LoadNKlass )
1020 return NULL;
1021 } else if (ldk1->Opcode() != Op_LoadKlass )
1022 return NULL;
1023 // Take apart the address of the LoadKlass:
1024 Node* adr1 = ldk1->in(MemNode::Address);
1025 intptr_t con2 = 0;
1026 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
1027 if (ldk2 == NULL)
1028 return NULL;
1029 if (con2 == oopDesc::klass_offset_in_bytes()) {
1030 // We are inspecting an object's concrete class.
1031 // Short-circuit the check if the query is abstract.
1032 if (superklass->is_interface() ||
1033 superklass->is_abstract()) {
1034 // Make it come out always false:
1035 this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
1036 return this;
1037 }
1038 }
1039
1040 // Check for a LoadKlass from primary supertype array.
1041 // Any nested loadklass from loadklass+con must be from the p.s. array.
1042 if (ldk2->is_DecodeNKlass()) {
1043 // Keep ldk2 as DecodeN since it could be used in CmpP below.
1044 if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
1045 return NULL;
1046 } else if (ldk2->Opcode() != Op_LoadKlass)
1047 return NULL;
1048
1049 // Verify that we understand the situation
1050 if (con2 != (intptr_t) superklass->super_check_offset())
1051 return NULL; // Might be element-klass loading from array klass
1052
1053 // If 'superklass' has no subklasses and is not an interface, then we are
1054 // assured that the only input which will pass the type check is
1055 // 'superklass' itself.
1056 //
1057 // We could be more liberal here, and allow the optimization on interfaces
1058 // which have a single implementor. This would require us to increase the
1059 // expressiveness of the add_dependency() mechanism.
1060 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now.
1061
1062 // Object arrays must have their base element have no subtypes
1063 while (superklass->is_obj_array_klass()) {
1064 ciType* elem = superklass->as_obj_array_klass()->element_type();
1065 superklass = elem->as_klass();
1066 }
1067 if (superklass->is_instance_klass()) {
1068 ciInstanceKlass* ik = superklass->as_instance_klass();
1069 if (ik->has_subklass() || ik->is_interface()) return NULL;
1070 // Add a dependency if there is a chance that a subclass will be added later.
1071 if (!ik->is_final()) {
1072 phase->C->dependencies()->assert_leaf_type(ik);
1073 }
1074 }
1075
1076 // Bypass the dependent load, and compare directly
1077 this->set_req(1,ldk2);
1078
1079 return this;
1080 }
1081
1082 //=============================================================================
1083 //------------------------------sub--------------------------------------------
1084 // Simplify an CmpN (compare 2 pointers) node, based on local information.
1085 // If both inputs are constants, compare them.
1086 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
1087 const TypePtr *r0 = t1->make_ptr(); // Handy access
1088 const TypePtr *r1 = t2->make_ptr();
1089
1090 // Undefined inputs makes for an undefined result
1091 if ((r0 == NULL) || (r1 == NULL) ||
1092 TypePtr::above_centerline(r0->_ptr) ||
1093 TypePtr::above_centerline(r1->_ptr)) {
1094 return Type::TOP;
1095 }
1096 if (r0 == r1 && r0->singleton()) {
1097 // Equal pointer constants (klasses, nulls, etc.)
1098 return TypeInt::CC_EQ;
1099 }
1100
1101 // See if it is 2 unrelated classes.
1102 const TypeOopPtr* p0 = r0->isa_oopptr();
1103 const TypeOopPtr* p1 = r1->isa_oopptr();
1104 if (p0 && p1) {
1105 ciKlass* klass0 = p0->klass();
1106 bool xklass0 = p0->klass_is_exact();
1107 ciKlass* klass1 = p1->klass();
1108 bool xklass1 = p1->klass_is_exact();
1109 int kps = (p0->isa_klassptr()?1:0) + (p1->isa_klassptr()?1:0);
1110 if (klass0 && klass1 &&
1111 kps != 1 && // both or neither are klass pointers
1112 !klass0->is_interface() && // do not trust interfaces
1113 !klass1->is_interface()) {
1114 bool unrelated_classes = false;
1115 // See if neither subclasses the other, or if the class on top
1116 // is precise. In either of these cases, the compare is known
1117 // to fail if at least one of the pointers is provably not null.
1118 if (klass0->equals(klass1)) { // if types are unequal but klasses are equal
1119 // Do nothing; we know nothing for imprecise types
1120 } else if (klass0->is_subtype_of(klass1)) {
1121 // If klass1's type is PRECISE, then classes are unrelated.
1122 unrelated_classes = xklass1;
1123 } else if (klass1->is_subtype_of(klass0)) {
1124 // If klass0's type is PRECISE, then classes are unrelated.
1125 unrelated_classes = xklass0;
1126 } else { // Neither subtypes the other
1127 unrelated_classes = true;
1128 }
1129 if (unrelated_classes) {
1130 // The oops classes are known to be unrelated. If the joined PTRs of
1131 // two oops is not Null and not Bottom, then we are sure that one
1132 // of the two oops is non-null, and the comparison will always fail.
1133 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
1134 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
1135 return TypeInt::CC_GT;
1136 }
1137 }
1138 }
1139 }
1140
1141 // Known constants can be compared exactly
1142 // Null can be distinguished from any NotNull pointers
1143 // Unknown inputs makes an unknown result
1144 if( r0->singleton() ) {
1145 intptr_t bits0 = r0->get_con();
1146 if( r1->singleton() )
1147 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
1148 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1149 } else if( r1->singleton() ) {
1150 intptr_t bits1 = r1->get_con();
1151 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1152 } else
1153 return TypeInt::CC;
1154 }
1155
1156 //------------------------------Ideal------------------------------------------
1157 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1158 return NULL;
1159 }
1160
1161 //=============================================================================
1162 //------------------------------Value------------------------------------------
1163 // Simplify an CmpF (compare 2 floats ) node, based on local information.
1164 // If both inputs are constants, compare them.
1165 const Type* CmpFNode::Value(PhaseGVN* phase) const {
1166 const Node* in1 = in(1);
1167 const Node* in2 = in(2);
1168 // Either input is TOP ==> the result is TOP
1169 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1170 if( t1 == Type::TOP ) return Type::TOP;
1171 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1172 if( t2 == Type::TOP ) return Type::TOP;
1173
1174 // Not constants? Don't know squat - even if they are the same
1175 // value! If they are NaN's they compare to LT instead of EQ.
1176 const TypeF *tf1 = t1->isa_float_constant();
1177 const TypeF *tf2 = t2->isa_float_constant();
1178 if( !tf1 || !tf2 ) return TypeInt::CC;
1179
1180 // This implements the Java bytecode fcmpl, so unordered returns -1.
1181 if( tf1->is_nan() || tf2->is_nan() )
1182 return TypeInt::CC_LT;
1183
1184 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
1185 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
1186 assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
1187 return TypeInt::CC_EQ;
1188 }
1189
1190
1191 //=============================================================================
1192 //------------------------------Value------------------------------------------
1193 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
1194 // If both inputs are constants, compare them.
1195 const Type* CmpDNode::Value(PhaseGVN* phase) const {
1196 const Node* in1 = in(1);
1197 const Node* in2 = in(2);
1198 // Either input is TOP ==> the result is TOP
1199 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1200 if( t1 == Type::TOP ) return Type::TOP;
1201 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1202 if( t2 == Type::TOP ) return Type::TOP;
1203
1204 // Not constants? Don't know squat - even if they are the same
1205 // value! If they are NaN's they compare to LT instead of EQ.
1206 const TypeD *td1 = t1->isa_double_constant();
1207 const TypeD *td2 = t2->isa_double_constant();
1208 if( !td1 || !td2 ) return TypeInt::CC;
1209
1210 // This implements the Java bytecode dcmpl, so unordered returns -1.
1211 if( td1->is_nan() || td2->is_nan() )
1212 return TypeInt::CC_LT;
1213
1214 if( td1->_d < td2->_d ) return TypeInt::CC_LT;
1215 if( td1->_d > td2->_d ) return TypeInt::CC_GT;
1216 assert( td1->_d == td2->_d, "do not understand FP behavior" );
1217 return TypeInt::CC_EQ;
1218 }
1219
1220 //------------------------------Ideal------------------------------------------
1221 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
1222 // Check if we can change this to a CmpF and remove a ConvD2F operation.
1223 // Change (CMPD (F2D (float)) (ConD value))
1224 // To (CMPF (float) (ConF value))
1225 // Valid when 'value' does not lose precision as a float.
1226 // Benefits: eliminates conversion, does not require 24-bit mode
1227
1228 // NaNs prevent commuting operands. This transform works regardless of the
1229 // order of ConD and ConvF2D inputs by preserving the original order.
1230 int idx_f2d = 1; // ConvF2D on left side?
1231 if( in(idx_f2d)->Opcode() != Op_ConvF2D )
1232 idx_f2d = 2; // No, swap to check for reversed args
1233 int idx_con = 3-idx_f2d; // Check for the constant on other input
1234
1235 if( ConvertCmpD2CmpF &&
1236 in(idx_f2d)->Opcode() == Op_ConvF2D &&
1237 in(idx_con)->Opcode() == Op_ConD ) {
1238 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
1239 double t2_value_as_double = t2->_d;
1240 float t2_value_as_float = (float)t2_value_as_double;
1241 if( t2_value_as_double == (double)t2_value_as_float ) {
1242 // Test value can be represented as a float
1243 // Eliminate the conversion to double and create new comparison
1244 Node *new_in1 = in(idx_f2d)->in(1);
1245 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
1246 if( idx_f2d != 1 ) { // Must flip args to match original order
1247 Node *tmp = new_in1;
1248 new_in1 = new_in2;
1249 new_in2 = tmp;
1250 }
1251 CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
1252 ? new CmpF3Node( new_in1, new_in2 )
1253 : new CmpFNode ( new_in1, new_in2 ) ;
1254 return new_cmp; // Changed to CmpFNode
1255 }
1256 // Testing value required the precision of a double
1257 }
1258 return NULL; // No change
1259 }
1260
1261
1262 //=============================================================================
1263 //------------------------------cc2logical-------------------------------------
1264 // Convert a condition code type to a logical type
1265 const Type *BoolTest::cc2logical( const Type *CC ) const {
1266 if( CC == Type::TOP ) return Type::TOP;
1267 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
1268 const TypeInt *ti = CC->is_int();
1269 if( ti->is_con() ) { // Only 1 kind of condition codes set?
1270 // Match low order 2 bits
1271 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
1272 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result
1273 return TypeInt::make(tmp); // Boolean result
1274 }
1275
1276 if( CC == TypeInt::CC_GE ) {
1277 if( _test == ge ) return TypeInt::ONE;
1278 if( _test == lt ) return TypeInt::ZERO;
1279 }
1280 if( CC == TypeInt::CC_LE ) {
1281 if( _test == le ) return TypeInt::ONE;
1282 if( _test == gt ) return TypeInt::ZERO;
1283 }
1284
1285 return TypeInt::BOOL;
1286 }
1287
1288 //------------------------------dump_spec-------------------------------------
1289 // Print special per-node info
1290 void BoolTest::dump_on(outputStream *st) const {
1291 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"};
1292 st->print("%s", msg[_test]);
1293 }
1294
1295 // Returns the logical AND of two tests (or 'never' if both tests can never be true).
1296 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'.
1297 BoolTest::mask BoolTest::merge(BoolTest other) const {
1298 const mask res[illegal+1][illegal+1] = {
1299 // eq, gt, of, lt, ne, le, nof, ge, never, illegal
1300 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq
1301 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt
1302 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of
1303 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt
1304 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne
1305 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le
1306 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof
1307 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge
1308 {never, never, never, never, never, never, never, never, never, illegal}, // never
1309 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal
1310 return res[_test][other._test];
1311 }
1312
1313 //=============================================================================
1314 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
1315 uint BoolNode::size_of() const { return sizeof(BoolNode); }
1316
1317 //------------------------------operator==-------------------------------------
1318 uint BoolNode::cmp( const Node &n ) const {
1319 const BoolNode *b = (const BoolNode *)&n; // Cast up
1320 return (_test._test == b->_test._test);
1321 }
1322
1323 //-------------------------------make_predicate--------------------------------
1324 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1325 if (test_value->is_Con()) return test_value;
1326 if (test_value->is_Bool()) return test_value;
1327 if (test_value->is_CMove() &&
1328 test_value->in(CMoveNode::Condition)->is_Bool()) {
1329 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool();
1330 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1331 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1332 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1333 return bol;
1334 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1335 return phase->transform( bol->negate(phase) );
1336 }
1337 // Else fall through. The CMove gets in the way of the test.
1338 // It should be the case that make_predicate(bol->as_int_value()) == bol.
1339 }
1340 Node* cmp = new CmpINode(test_value, phase->intcon(0));
1341 cmp = phase->transform(cmp);
1342 Node* bol = new BoolNode(cmp, BoolTest::ne);
1343 return phase->transform(bol);
1344 }
1345
1346 //--------------------------------as_int_value---------------------------------
1347 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1348 // Inverse to make_predicate. The CMove probably boils down to a Conv2B.
1349 Node* cmov = CMoveNode::make(NULL, this,
1350 phase->intcon(0), phase->intcon(1),
1351 TypeInt::BOOL);
1352 return phase->transform(cmov);
1353 }
1354
1355 //----------------------------------negate-------------------------------------
1356 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1357 return new BoolNode(in(1), _test.negate());
1358 }
1359
1360 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub
1361 // overflows and we can prove that C is not in the two resulting ranges.
1362 // This optimization is similar to the one performed by CmpUNode::Value().
1363 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op,
1364 int cmp1_op, const TypeInt* cmp2_type) {
1365 // Only optimize eq/ne integer comparison of add/sub
1366 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1367 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) {
1368 // Skip cases were inputs of add/sub are not integers or of bottom type
1369 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int();
1370 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int();
1371 if ((r0 != NULL) && (r0 != TypeInt::INT) &&
1372 (r1 != NULL) && (r1 != TypeInt::INT) &&
1373 (cmp2_type != TypeInt::INT)) {
1374 // Compute exact (long) type range of add/sub result
1375 jlong lo_long = r0->_lo;
1376 jlong hi_long = r0->_hi;
1377 if (cmp1_op == Op_AddI) {
1378 lo_long += r1->_lo;
1379 hi_long += r1->_hi;
1380 } else {
1381 lo_long -= r1->_hi;
1382 hi_long -= r1->_lo;
1383 }
1384 // Check for over-/underflow by casting to integer
1385 int lo_int = (int)lo_long;
1386 int hi_int = (int)hi_long;
1387 bool underflow = lo_long != (jlong)lo_int;
1388 bool overflow = hi_long != (jlong)hi_int;
1389 if ((underflow != overflow) && (hi_int < lo_int)) {
1390 // Overflow on one boundary, compute resulting type ranges:
1391 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT]
1392 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
1393 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w);
1394 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w);
1395 // Compare second input of cmp to both type ranges
1396 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type);
1397 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type);
1398 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) {
1399 // The result of the add/sub will never equal cmp2. Replace BoolNode
1400 // by false (0) if it tests for equality and by true (1) otherwise.
1401 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1);
1402 }
1403 }
1404 }
1405 }
1406 return NULL;
1407 }
1408
1409 static bool is_counted_loop_cmp(Node *cmp) {
1410 Node *n = cmp->in(1)->in(1);
1411 return n != NULL &&
1412 n->is_Phi() &&
1413 n->in(0) != NULL &&
1414 n->in(0)->is_CountedLoop() &&
1415 n->in(0)->as_CountedLoop()->phi() == n;
1416 }
1417
1418 //------------------------------Ideal------------------------------------------
1419 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1420 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1421 // This moves the constant to the right. Helps value-numbering.
1422 Node *cmp = in(1);
1423 if( !cmp->is_Sub() ) return NULL;
1424 int cop = cmp->Opcode();
1425 if( cop == Op_FastLock || cop == Op_FastUnlock) return NULL;
1426 Node *cmp1 = cmp->in(1);
1427 Node *cmp2 = cmp->in(2);
1428 if( !cmp1 ) return NULL;
1429
1430 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) {
1431 return NULL;
1432 }
1433
1434 // Constant on left?
1435 Node *con = cmp1;
1436 uint op2 = cmp2->Opcode();
1437 // Move constants to the right of compare's to canonicalize.
1438 // Do not muck with Opaque1 nodes, as this indicates a loop
1439 // guard that cannot change shape.
1440 if( con->is_Con() && !cmp2->is_Con() && op2 != Op_Opaque1 &&
1441 // Because of NaN's, CmpD and CmpF are not commutative
1442 cop != Op_CmpD && cop != Op_CmpF &&
1443 // Protect against swapping inputs to a compare when it is used by a
1444 // counted loop exit, which requires maintaining the loop-limit as in(2)
1445 !is_counted_loop_exit_test() ) {
1446 // Ok, commute the constant to the right of the cmp node.
1447 // Clone the Node, getting a new Node of the same class
1448 cmp = cmp->clone();
1449 // Swap inputs to the clone
1450 cmp->swap_edges(1, 2);
1451 cmp = phase->transform( cmp );
1452 return new BoolNode( cmp, _test.commute() );
1453 }
1454
1455 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1456 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the
1457 // test instead.
1458 int cmp1_op = cmp1->Opcode();
1459 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1460 if (cmp2_type == NULL) return NULL;
1461 Node* j_xor = cmp1;
1462 if( cmp2_type == TypeInt::ZERO &&
1463 cmp1_op == Op_XorI &&
1464 j_xor->in(1) != j_xor && // An xor of itself is dead
1465 phase->type( j_xor->in(1) ) == TypeInt::BOOL &&
1466 phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1467 (_test._test == BoolTest::eq ||
1468 _test._test == BoolTest::ne) ) {
1469 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2));
1470 return new BoolNode( ncmp, _test.negate() );
1471 }
1472
1473 // Change ((x & m) u<= m) or ((m & x) u<= m) to always true
1474 // Same with ((x & m) u< m+1) and ((m & x) u< m+1)
1475 if (cop == Op_CmpU &&
1476 cmp1_op == Op_AndI) {
1477 Node* bound = NULL;
1478 if (_test._test == BoolTest::le) {
1479 bound = cmp2;
1480 } else if (_test._test == BoolTest::lt &&
1481 cmp2->Opcode() == Op_AddI &&
1482 cmp2->in(2)->find_int_con(0) == 1) {
1483 bound = cmp2->in(1);
1484 }
1485 if (cmp1->in(2) == bound || cmp1->in(1) == bound) {
1486 return ConINode::make(1);
1487 }
1488 }
1489
1490 // Change ((x & (m - 1)) u< m) into (m > 0)
1491 // This is the off-by-one variant of the above
1492 if (cop == Op_CmpU &&
1493 _test._test == BoolTest::lt &&
1494 cmp1_op == Op_AndI) {
1495 Node* l = cmp1->in(1);
1496 Node* r = cmp1->in(2);
1497 for (int repeat = 0; repeat < 2; repeat++) {
1498 bool match = r->Opcode() == Op_AddI && r->in(2)->find_int_con(0) == -1 &&
1499 r->in(1) == cmp2;
1500 if (match) {
1501 // arraylength known to be non-negative, so a (arraylength != 0) is sufficient,
1502 // but to be compatible with the array range check pattern, use (arraylength u> 0)
1503 Node* ncmp = cmp2->Opcode() == Op_LoadRange
1504 ? phase->transform(new CmpUNode(cmp2, phase->intcon(0)))
1505 : phase->transform(new CmpINode(cmp2, phase->intcon(0)));
1506 return new BoolNode(ncmp, BoolTest::gt);
1507 } else {
1508 // commute and try again
1509 l = cmp1->in(2);
1510 r = cmp1->in(1);
1511 }
1512 }
1513 }
1514
1515 // Change x u< 1 or x u<= 0 to x == 0
1516 if (cop == Op_CmpU &&
1517 cmp1_op != Op_LoadRange &&
1518 ((_test._test == BoolTest::lt &&
1519 cmp2->find_int_con(-1) == 1) ||
1520 (_test._test == BoolTest::le &&
1521 cmp2->find_int_con(-1) == 0))) {
1522 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1523 return new BoolNode(ncmp, BoolTest::eq);
1524 }
1525
1526 // Change (arraylength <= 0) or (arraylength == 0)
1527 // into (arraylength u<= 0)
1528 // Also change (arraylength != 0) into (arraylength u> 0)
1529 // The latter version matches the code pattern generated for
1530 // array range checks, which will more likely be optimized later.
1531 if (cop == Op_CmpI &&
1532 cmp1_op == Op_LoadRange &&
1533 cmp2->find_int_con(-1) == 0) {
1534 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) {
1535 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1536 return new BoolNode(ncmp, BoolTest::le);
1537 } else if (_test._test == BoolTest::ne) {
1538 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1539 return new BoolNode(ncmp, BoolTest::gt);
1540 }
1541 }
1542
1543 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1544 // This is a standard idiom for branching on a boolean value.
1545 Node *c2b = cmp1;
1546 if( cmp2_type == TypeInt::ZERO &&
1547 cmp1_op == Op_Conv2B &&
1548 (_test._test == BoolTest::eq ||
1549 _test._test == BoolTest::ne) ) {
1550 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1551 ? (Node*)new CmpINode(c2b->in(1),cmp2)
1552 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1553 );
1554 return new BoolNode( ncmp, _test._test );
1555 }
1556
1557 // Comparing a SubI against a zero is equal to comparing the SubI
1558 // arguments directly. This only works for eq and ne comparisons
1559 // due to possible integer overflow.
1560 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1561 (cop == Op_CmpI) &&
1562 (cmp1_op == Op_SubI) &&
1563 ( cmp2_type == TypeInt::ZERO ) ) {
1564 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2)));
1565 return new BoolNode( ncmp, _test._test );
1566 }
1567
1568 // Same as above but with and AddI of a constant
1569 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1570 cop == Op_CmpI &&
1571 cmp1_op == Op_AddI &&
1572 cmp1->in(2) != NULL &&
1573 phase->type(cmp1->in(2))->isa_int() &&
1574 phase->type(cmp1->in(2))->is_int()->is_con() &&
1575 cmp2_type == TypeInt::ZERO &&
1576 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape
1577 ) {
1578 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int();
1579 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi)));
1580 return new BoolNode( ncmp, _test._test );
1581 }
1582
1583 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)"
1584 // since zero check of conditional negation of an integer is equal to
1585 // zero check of the integer directly.
1586 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1587 (cop == Op_CmpI) &&
1588 (cmp2_type == TypeInt::ZERO) &&
1589 (cmp1_op == Op_Phi)) {
1590 // There should be a diamond phi with true path at index 1 or 2
1591 PhiNode *phi = cmp1->as_Phi();
1592 int idx_true = phi->is_diamond_phi();
1593 if (idx_true != 0) {
1594 // True input is in(idx_true) while false input is in(3 - idx_true)
1595 Node *tin = phi->in(idx_true);
1596 Node *fin = phi->in(3 - idx_true);
1597 if ((tin->Opcode() == Op_SubI) &&
1598 (phase->type(tin->in(1)) == TypeInt::ZERO) &&
1599 (tin->in(2) == fin)) {
1600 // Found conditional negation at true path, create a new CmpINode without that
1601 Node *ncmp = phase->transform(new CmpINode(fin, cmp2));
1602 return new BoolNode(ncmp, _test._test);
1603 }
1604 if ((fin->Opcode() == Op_SubI) &&
1605 (phase->type(fin->in(1)) == TypeInt::ZERO) &&
1606 (fin->in(2) == tin)) {
1607 // Found conditional negation at false path, create a new CmpINode without that
1608 Node *ncmp = phase->transform(new CmpINode(tin, cmp2));
1609 return new BoolNode(ncmp, _test._test);
1610 }
1611 }
1612 }
1613
1614 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the
1615 // most general case because negating 0x80000000 does nothing. Needed for
1616 // the CmpF3/SubI/CmpI idiom.
1617 if( cop == Op_CmpI &&
1618 cmp1_op == Op_SubI &&
1619 cmp2_type == TypeInt::ZERO &&
1620 phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1621 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1622 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2));
1623 return new BoolNode( ncmp, _test.commute() );
1624 }
1625
1626 // Try to optimize signed integer comparison
1627 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type);
1628
1629 // The transformation below is not valid for either signed or unsigned
1630 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1631 // This transformation can be resurrected when we are able to
1632 // make inferences about the range of values being subtracted from
1633 // (or added to) relative to the wraparound point.
1634 //
1635 // // Remove +/-1's if possible.
1636 // // "X <= Y-1" becomes "X < Y"
1637 // // "X+1 <= Y" becomes "X < Y"
1638 // // "X < Y+1" becomes "X <= Y"
1639 // // "X-1 < Y" becomes "X <= Y"
1640 // // Do not this to compares off of the counted-loop-end. These guys are
1641 // // checking the trip counter and they want to use the post-incremented
1642 // // counter. If they use the PRE-incremented counter, then the counter has
1643 // // to be incremented in a private block on a loop backedge.
1644 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1645 // return NULL;
1646 // #ifndef PRODUCT
1647 // // Do not do this in a wash GVN pass during verification.
1648 // // Gets triggered by too many simple optimizations to be bothered with
1649 // // re-trying it again and again.
1650 // if( !phase->allow_progress() ) return NULL;
1651 // #endif
1652 // // Not valid for unsigned compare because of corner cases in involving zero.
1653 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1654 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1655 // // "0 <=u Y" is always true).
1656 // if( cmp->Opcode() == Op_CmpU ) return NULL;
1657 // int cmp2_op = cmp2->Opcode();
1658 // if( _test._test == BoolTest::le ) {
1659 // if( cmp1_op == Op_AddI &&
1660 // phase->type( cmp1->in(2) ) == TypeInt::ONE )
1661 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1662 // else if( cmp2_op == Op_AddI &&
1663 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1664 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1665 // } else if( _test._test == BoolTest::lt ) {
1666 // if( cmp1_op == Op_AddI &&
1667 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1668 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1669 // else if( cmp2_op == Op_AddI &&
1670 // phase->type( cmp2->in(2) ) == TypeInt::ONE )
1671 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1672 // }
1673 }
1674
1675 //------------------------------Value------------------------------------------
1676 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
1677 // based on local information. If the input is constant, do it.
1678 const Type* BoolNode::Value(PhaseGVN* phase) const {
1679 return _test.cc2logical( phase->type( in(1) ) );
1680 }
1681
1682 #ifndef PRODUCT
1683 //------------------------------dump_spec--------------------------------------
1684 // Dump special per-node info
1685 void BoolNode::dump_spec(outputStream *st) const {
1686 st->print("[");
1687 _test.dump_on(st);
1688 st->print("]");
1689 }
1690
1691 //-------------------------------related---------------------------------------
1692 // A BoolNode's related nodes are all of its data inputs, and all of its
1693 // outputs until control nodes are hit, which are included. In compact
1694 // representation, inputs till level 3 and immediate outputs are included.
1695 void BoolNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
1696 if (compact) {
1697 this->collect_nodes(in_rel, 3, false, true);
1698 this->collect_nodes(out_rel, -1, false, false);
1699 } else {
1700 this->collect_nodes_in_all_data(in_rel, false);
1701 this->collect_nodes_out_all_ctrl_boundary(out_rel);
1702 }
1703 }
1704 #endif
1705
1706 //----------------------is_counted_loop_exit_test------------------------------
1707 // Returns true if node is used by a counted loop node.
1708 bool BoolNode::is_counted_loop_exit_test() {
1709 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
1710 Node* use = fast_out(i);
1711 if (use->is_CountedLoopEnd()) {
1712 return true;
1713 }
1714 }
1715 return false;
1716 }
1717
1718 //=============================================================================
1719 //------------------------------Value------------------------------------------
1720 // Compute sqrt
1721 const Type* SqrtDNode::Value(PhaseGVN* phase) const {
1722 const Type *t1 = phase->type( in(1) );
1723 if( t1 == Type::TOP ) return Type::TOP;
1724 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1725 double d = t1->getd();
1726 if( d < 0.0 ) return Type::DOUBLE;
1727 return TypeD::make( sqrt( d ) );
1728 }
1729
1730 const Type* SqrtFNode::Value(PhaseGVN* phase) const {
1731 const Type *t1 = phase->type( in(1) );
1732 if( t1 == Type::TOP ) return Type::TOP;
1733 if( t1->base() != Type::FloatCon ) return Type::FLOAT;
1734 float f = t1->getf();
1735 if( f < 0.0f ) return Type::FLOAT;
1736 return TypeF::make( (float)sqrt( (double)f ) );
1737 }