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.
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.
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23 */
24
25 #include "precompiled.hpp"
26 #include "compiler/compileLog.hpp"
27 #include "memory/allocation.inline.hpp"
28 #include "opto/addnode.hpp"
29 #include "opto/callnode.hpp"
30 #include "opto/cfgnode.hpp"
31 #include "opto/loopnode.hpp"
32 #include "opto/matcher.hpp"
33 #include "opto/movenode.hpp"
34 #include "opto/mulnode.hpp"
35 #include "opto/opcodes.hpp"
36 #include "opto/phaseX.hpp"
37 #include "opto/subnode.hpp"
38 #include "runtime/sharedRuntime.hpp"
39 #include "utilities/macros.hpp"
40 #if INCLUDE_SHENANDOAHGC
41 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
42 #endif
43
44 // Portions of code courtesy of Clifford Click
45
46 // Optimization - Graph Style
47
48 #include "math.h"
49
50 //=============================================================================
51 //------------------------------Identity---------------------------------------
52 // If right input is a constant 0, return the left input.
53 Node* SubNode::Identity(PhaseGVN* phase) {
54 assert(in(1) != this, "Must already have called Value");
55 assert(in(2) != this, "Must already have called Value");
56
57 // Remove double negation
58 const Type *zero = add_id();
59 if( phase->type( in(1) )->higher_equal( zero ) &&
60 in(2)->Opcode() == Opcode() &&
61 phase->type( in(2)->in(1) )->higher_equal( zero ) ) {
62 return in(2)->in(2);
63 }
64
65 // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y
66 if( in(1)->Opcode() == Op_AddI ) {
67 if( phase->eqv(in(1)->in(2),in(2)) )
68 return in(1)->in(1);
69 if (phase->eqv(in(1)->in(1),in(2)))
70 return in(1)->in(2);
71
72 // Also catch: "(X + Opaque2(Y)) - Y". In this case, 'Y' is a loop-varying
73 // trip counter and X is likely to be loop-invariant (that's how O2 Nodes
74 // are originally used, although the optimizer sometimes jiggers things).
75 // This folding through an O2 removes a loop-exit use of a loop-varying
76 // value and generally lowers register pressure in and around the loop.
77 if( in(1)->in(2)->Opcode() == Op_Opaque2 &&
78 phase->eqv(in(1)->in(2)->in(1),in(2)) )
79 return in(1)->in(1);
80 }
81
82 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this;
83 }
84
85 //------------------------------Value------------------------------------------
86 // A subtract node differences it's two inputs.
87 const Type* SubNode::Value_common(PhaseTransform *phase) const {
88 const Node* in1 = in(1);
89 const Node* in2 = in(2);
90 // Either input is TOP ==> the result is TOP
91 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
92 if( t1 == Type::TOP ) return Type::TOP;
93 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
94 if( t2 == Type::TOP ) return Type::TOP;
95
96 // Not correct for SubFnode and AddFNode (must check for infinity)
97 // Equal? Subtract is zero
98 if (in1->eqv_uncast(in2)) return add_id();
99
100 // Either input is BOTTOM ==> the result is the local BOTTOM
101 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM )
102 return bottom_type();
103
104 return NULL;
105 }
106
107 const Type* SubNode::Value(PhaseGVN* phase) const {
108 const Type* t = Value_common(phase);
109 if (t != NULL) {
110 return t;
111 }
112 Node* in1 = in(1);
113 Node* in2 = in(2);
114 #if INCLUDE_SHENANDOAHGC
115 if (Opcode() == Op_CmpP) {
116 Node* n = ShenandoahBarrierNode::skip_through_barrier(in1);
117 if (!n->is_top()) {
118 in1 = n;
119 }
120 n = ShenandoahBarrierNode::skip_through_barrier(in2);
121 if (!n->is_top()) {
122 in2 = n;
123 }
124 }
125 #endif
126 const Type* t1 = phase->type(in1);
127 const Type* t2 = phase->type(in2);
128 return sub(t1,t2); // Local flavor of type subtraction
129
130 }
131
132 //=============================================================================
133
134 //------------------------------Helper function--------------------------------
135 static bool ok_to_convert(Node* inc, Node* iv) {
136 // Do not collapse (x+c0)-y if "+" is a loop increment, because the
137 // "-" is loop invariant and collapsing extends the live-range of "x"
138 // to overlap with the "+", forcing another register to be used in
139 // the loop.
140 // This test will be clearer with '&&' (apply DeMorgan's rule)
141 // but I like the early cutouts that happen here.
142 const PhiNode *phi;
143 if( ( !inc->in(1)->is_Phi() ||
144 !(phi=inc->in(1)->as_Phi()) ||
145 phi->is_copy() ||
146 !phi->region()->is_CountedLoop() ||
147 inc != phi->region()->as_CountedLoop()->incr() )
148 &&
149 // Do not collapse (x+c0)-iv if "iv" is a loop induction variable,
150 // because "x" maybe invariant.
151 ( !iv->is_loop_iv() )
152 ) {
153 return true;
154 } else {
155 return false;
156 }
157 }
158 //------------------------------Ideal------------------------------------------
159 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){
160 Node *in1 = in(1);
161 Node *in2 = in(2);
162 uint op1 = in1->Opcode();
163 uint op2 = in2->Opcode();
164
165 #ifdef ASSERT
166 // Check for dead loop
167 if( phase->eqv( in1, this ) || phase->eqv( in2, this ) ||
168 ( ( op1 == Op_AddI || op1 == Op_SubI ) &&
169 ( phase->eqv( in1->in(1), this ) || phase->eqv( in1->in(2), this ) ||
170 phase->eqv( in1->in(1), in1 ) || phase->eqv( in1->in(2), in1 ) ) ) )
171 assert(false, "dead loop in SubINode::Ideal");
172 #endif
173
174 const Type *t2 = phase->type( in2 );
175 if( t2 == Type::TOP ) return NULL;
176 // Convert "x-c0" into "x+ -c0".
177 if( t2->base() == Type::Int ){ // Might be bottom or top...
178 const TypeInt *i = t2->is_int();
179 if( i->is_con() )
180 return new AddINode(in1, phase->intcon(-i->get_con()));
181 }
182
183 // Convert "(x+c0) - y" into (x-y) + c0"
184 // Do not collapse (x+c0)-y if "+" is a loop increment or
185 // if "y" is a loop induction variable.
186 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) {
187 const Type *tadd = phase->type( in1->in(2) );
188 if( tadd->singleton() && tadd != Type::TOP ) {
189 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 ));
190 return new AddINode( sub2, in1->in(2) );
191 }
192 }
193
194
195 // Convert "x - (y+c0)" into "(x-y) - c0"
196 // Need the same check as in above optimization but reversed.
197 if (op2 == Op_AddI && ok_to_convert(in2, in1)) {
198 Node* in21 = in2->in(1);
199 Node* in22 = in2->in(2);
200 const TypeInt* tcon = phase->type(in22)->isa_int();
201 if (tcon != NULL && tcon->is_con()) {
202 Node* sub2 = phase->transform( new SubINode(in1, in21) );
203 Node* neg_c0 = phase->intcon(- tcon->get_con());
204 return new AddINode(sub2, neg_c0);
205 }
206 }
207
208 const Type *t1 = phase->type( in1 );
209 if( t1 == Type::TOP ) return NULL;
210
211 #ifdef ASSERT
212 // Check for dead loop
213 if( ( op2 == Op_AddI || op2 == Op_SubI ) &&
214 ( phase->eqv( in2->in(1), this ) || phase->eqv( in2->in(2), this ) ||
215 phase->eqv( in2->in(1), in2 ) || phase->eqv( in2->in(2), in2 ) ) )
216 assert(false, "dead loop in SubINode::Ideal");
217 #endif
218
219 // Convert "x - (x+y)" into "-y"
220 if( op2 == Op_AddI &&
221 phase->eqv( in1, in2->in(1) ) )
222 return new SubINode( phase->intcon(0),in2->in(2));
223 // Convert "(x-y) - x" into "-y"
224 if( op1 == Op_SubI &&
225 phase->eqv( in1->in(1), in2 ) )
226 return new SubINode( phase->intcon(0),in1->in(2));
227 // Convert "x - (y+x)" into "-y"
228 if( op2 == Op_AddI &&
229 phase->eqv( in1, in2->in(2) ) )
230 return new SubINode( phase->intcon(0),in2->in(1));
231
232 // Convert "0 - (x-y)" into "y-x"
233 if( t1 == TypeInt::ZERO && op2 == Op_SubI )
234 return new SubINode( in2->in(2), in2->in(1) );
235
236 // Convert "0 - (x+con)" into "-con-x"
237 jint con;
238 if( t1 == TypeInt::ZERO && op2 == Op_AddI &&
239 (con = in2->in(2)->find_int_con(0)) != 0 )
240 return new SubINode( phase->intcon(-con), in2->in(1) );
241
242 // Convert "(X+A) - (X+B)" into "A - B"
243 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) )
244 return new SubINode( in1->in(2), in2->in(2) );
245
246 // Convert "(A+X) - (B+X)" into "A - B"
247 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) )
248 return new SubINode( in1->in(1), in2->in(1) );
249
250 // Convert "(A+X) - (X+B)" into "A - B"
251 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) )
252 return new SubINode( in1->in(1), in2->in(2) );
253
254 // Convert "(X+A) - (B+X)" into "A - B"
255 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) )
256 return new SubINode( in1->in(2), in2->in(1) );
257
258 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally
259 // nicer to optimize than subtract.
260 if( op2 == Op_SubI && in2->outcnt() == 1) {
261 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) );
262 return new SubINode( add1, in2->in(1) );
263 }
264
265 return NULL;
266 }
267
268 //------------------------------sub--------------------------------------------
269 // A subtract node differences it's two inputs.
270 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const {
271 const TypeInt *r0 = t1->is_int(); // Handy access
272 const TypeInt *r1 = t2->is_int();
273 int32_t lo = java_subtract(r0->_lo, r1->_hi);
274 int32_t hi = java_subtract(r0->_hi, r1->_lo);
275
276 // We next check for 32-bit overflow.
277 // If that happens, we just assume all integers are possible.
278 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
279 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
280 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
281 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
282 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen));
283 else // Overflow; assume all integers
284 return TypeInt::INT;
285 }
286
287 //=============================================================================
288 //------------------------------Ideal------------------------------------------
289 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
290 Node *in1 = in(1);
291 Node *in2 = in(2);
292 uint op1 = in1->Opcode();
293 uint op2 = in2->Opcode();
294
295 #ifdef ASSERT
296 // Check for dead loop
297 if( phase->eqv( in1, this ) || phase->eqv( in2, this ) ||
298 ( ( op1 == Op_AddL || op1 == Op_SubL ) &&
299 ( phase->eqv( in1->in(1), this ) || phase->eqv( in1->in(2), this ) ||
300 phase->eqv( in1->in(1), in1 ) || phase->eqv( in1->in(2), in1 ) ) ) )
301 assert(false, "dead loop in SubLNode::Ideal");
302 #endif
303
304 if( phase->type( in2 ) == Type::TOP ) return NULL;
305 const TypeLong *i = phase->type( in2 )->isa_long();
306 // Convert "x-c0" into "x+ -c0".
307 if( i && // Might be bottom or top...
308 i->is_con() )
309 return new AddLNode(in1, phase->longcon(-i->get_con()));
310
311 // Convert "(x+c0) - y" into (x-y) + c0"
312 // Do not collapse (x+c0)-y if "+" is a loop increment or
313 // if "y" is a loop induction variable.
314 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) {
315 Node *in11 = in1->in(1);
316 const Type *tadd = phase->type( in1->in(2) );
317 if( tadd->singleton() && tadd != Type::TOP ) {
318 Node *sub2 = phase->transform( new SubLNode( in11, in2 ));
319 return new AddLNode( sub2, in1->in(2) );
320 }
321 }
322
323 // Convert "x - (y+c0)" into "(x-y) - c0"
324 // Need the same check as in above optimization but reversed.
325 if (op2 == Op_AddL && ok_to_convert(in2, in1)) {
326 Node* in21 = in2->in(1);
327 Node* in22 = in2->in(2);
328 const TypeLong* tcon = phase->type(in22)->isa_long();
329 if (tcon != NULL && tcon->is_con()) {
330 Node* sub2 = phase->transform( new SubLNode(in1, in21) );
331 Node* neg_c0 = phase->longcon(- tcon->get_con());
332 return new AddLNode(sub2, neg_c0);
333 }
334 }
335
336 const Type *t1 = phase->type( in1 );
337 if( t1 == Type::TOP ) return NULL;
338
339 #ifdef ASSERT
340 // Check for dead loop
341 if( ( op2 == Op_AddL || op2 == Op_SubL ) &&
342 ( phase->eqv( in2->in(1), this ) || phase->eqv( in2->in(2), this ) ||
343 phase->eqv( in2->in(1), in2 ) || phase->eqv( in2->in(2), in2 ) ) )
344 assert(false, "dead loop in SubLNode::Ideal");
345 #endif
346
347 // Convert "x - (x+y)" into "-y"
348 if( op2 == Op_AddL &&
349 phase->eqv( in1, in2->in(1) ) )
350 return new SubLNode( phase->makecon(TypeLong::ZERO), in2->in(2));
351 // Convert "x - (y+x)" into "-y"
352 if( op2 == Op_AddL &&
353 phase->eqv( in1, in2->in(2) ) )
354 return new SubLNode( phase->makecon(TypeLong::ZERO),in2->in(1));
355
356 // Convert "0 - (x-y)" into "y-x"
357 if( phase->type( in1 ) == TypeLong::ZERO && op2 == Op_SubL )
358 return new SubLNode( in2->in(2), in2->in(1) );
359
360 // Convert "(X+A) - (X+B)" into "A - B"
361 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) )
362 return new SubLNode( in1->in(2), in2->in(2) );
363
364 // Convert "(A+X) - (B+X)" into "A - B"
365 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) )
366 return new SubLNode( in1->in(1), in2->in(1) );
367
368 // Convert "A-(B-C)" into (A+C)-B"
369 if( op2 == Op_SubL && in2->outcnt() == 1) {
370 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) );
371 return new SubLNode( add1, in2->in(1) );
372 }
373
374 return NULL;
375 }
376
377 //------------------------------sub--------------------------------------------
378 // A subtract node differences it's two inputs.
379 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const {
380 const TypeLong *r0 = t1->is_long(); // Handy access
381 const TypeLong *r1 = t2->is_long();
382 jlong lo = java_subtract(r0->_lo, r1->_hi);
383 jlong hi = java_subtract(r0->_hi, r1->_lo);
384
385 // We next check for 32-bit overflow.
386 // If that happens, we just assume all integers are possible.
387 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
388 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
389 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
390 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
391 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen));
392 else // Overflow; assume all integers
393 return TypeLong::LONG;
394 }
395
396 //=============================================================================
397 //------------------------------Value------------------------------------------
398 // A subtract node differences its two inputs.
399 const Type* SubFPNode::Value(PhaseGVN* phase) const {
400 const Node* in1 = in(1);
401 const Node* in2 = in(2);
402 // Either input is TOP ==> the result is TOP
403 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
404 if( t1 == Type::TOP ) return Type::TOP;
405 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
406 if( t2 == Type::TOP ) return Type::TOP;
407
408 // if both operands are infinity of same sign, the result is NaN; do
409 // not replace with zero
410 if( (t1->is_finite() && t2->is_finite()) ) {
411 if( phase->eqv(in1, in2) ) return add_id();
412 }
413
414 // Either input is BOTTOM ==> the result is the local BOTTOM
415 const Type *bot = bottom_type();
416 if( (t1 == bot) || (t2 == bot) ||
417 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
418 return bot;
419
420 return sub(t1,t2); // Local flavor of type subtraction
421 }
422
423
424 //=============================================================================
425 //------------------------------Ideal------------------------------------------
426 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
427 const Type *t2 = phase->type( in(2) );
428 // Convert "x-c0" into "x+ -c0".
429 if( t2->base() == Type::FloatCon ) { // Might be bottom or top...
430 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) );
431 }
432
433 // Not associative because of boundary conditions (infinity)
434 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
435 // Convert "x - (x+y)" into "-y"
436 if( in(2)->is_Add() &&
437 phase->eqv(in(1),in(2)->in(1) ) )
438 return new SubFNode( phase->makecon(TypeF::ZERO),in(2)->in(2));
439 }
440
441 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes
442 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0.
443 //if( phase->type(in(1)) == TypeF::ZERO )
444 //return new (phase->C, 2) NegFNode(in(2));
445
446 return NULL;
447 }
448
449 //------------------------------sub--------------------------------------------
450 // A subtract node differences its two inputs.
451 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const {
452 // no folding if one of operands is infinity or NaN, do not do constant folding
453 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) {
454 return TypeF::make( t1->getf() - t2->getf() );
455 }
456 else if( g_isnan(t1->getf()) ) {
457 return t1;
458 }
459 else if( g_isnan(t2->getf()) ) {
460 return t2;
461 }
462 else {
463 return Type::FLOAT;
464 }
465 }
466
467 //=============================================================================
468 //------------------------------Ideal------------------------------------------
469 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){
470 const Type *t2 = phase->type( in(2) );
471 // Convert "x-c0" into "x+ -c0".
472 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top...
473 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) );
474 }
475
476 // Not associative because of boundary conditions (infinity)
477 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
478 // Convert "x - (x+y)" into "-y"
479 if( in(2)->is_Add() &&
480 phase->eqv(in(1),in(2)->in(1) ) )
481 return new SubDNode( phase->makecon(TypeD::ZERO),in(2)->in(2));
482 }
483
484 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes
485 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0.
486 //if( phase->type(in(1)) == TypeD::ZERO )
487 //return new (phase->C, 2) NegDNode(in(2));
488
489 return NULL;
490 }
491
492 //------------------------------sub--------------------------------------------
493 // A subtract node differences its two inputs.
494 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const {
495 // no folding if one of operands is infinity or NaN, do not do constant folding
496 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) {
497 return TypeD::make( t1->getd() - t2->getd() );
498 }
499 else if( g_isnan(t1->getd()) ) {
500 return t1;
501 }
502 else if( g_isnan(t2->getd()) ) {
503 return t2;
504 }
505 else {
506 return Type::DOUBLE;
507 }
508 }
509
510 //=============================================================================
511 //------------------------------Idealize---------------------------------------
512 // Unlike SubNodes, compare must still flatten return value to the
513 // range -1, 0, 1.
514 // And optimizations like those for (X + Y) - X fail if overflow happens.
515 Node* CmpNode::Identity(PhaseGVN* phase) {
516 return this;
517 }
518
519 #ifndef PRODUCT
520 //----------------------------related------------------------------------------
521 // Related nodes of comparison nodes include all data inputs (until hitting a
522 // control boundary) as well as all outputs until and including control nodes
523 // as well as their projections. In compact mode, data inputs till depth 1 and
524 // all outputs till depth 1 are considered.
525 void CmpNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
526 if (compact) {
527 this->collect_nodes(in_rel, 1, false, true);
528 this->collect_nodes(out_rel, -1, false, false);
529 } else {
530 this->collect_nodes_in_all_data(in_rel, false);
531 this->collect_nodes_out_all_ctrl_boundary(out_rel);
532 // Now, find all control nodes in out_rel, and include their projections
533 // and projection targets (if any) in the result.
534 GrowableArray<Node*> proj(Compile::current()->unique());
535 for (GrowableArrayIterator<Node*> it = out_rel->begin(); it != out_rel->end(); ++it) {
536 Node* n = *it;
537 if (n->is_CFG() && !n->is_Proj()) {
538 // Assume projections and projection targets are found at levels 1 and 2.
539 n->collect_nodes(&proj, -2, false, false);
540 for (GrowableArrayIterator<Node*> p = proj.begin(); p != proj.end(); ++p) {
541 out_rel->append_if_missing(*p);
542 }
543 proj.clear();
544 }
545 }
546 }
547 }
548 #endif
549
550 //=============================================================================
551 //------------------------------cmp--------------------------------------------
552 // Simplify a CmpI (compare 2 integers) node, based on local information.
553 // If both inputs are constants, compare them.
554 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const {
555 const TypeInt *r0 = t1->is_int(); // Handy access
556 const TypeInt *r1 = t2->is_int();
557
558 if( r0->_hi < r1->_lo ) // Range is always low?
559 return TypeInt::CC_LT;
560 else if( r0->_lo > r1->_hi ) // Range is always high?
561 return TypeInt::CC_GT;
562
563 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
564 assert(r0->get_con() == r1->get_con(), "must be equal");
565 return TypeInt::CC_EQ; // Equal results.
566 } else if( r0->_hi == r1->_lo ) // Range is never high?
567 return TypeInt::CC_LE;
568 else if( r0->_lo == r1->_hi ) // Range is never low?
569 return TypeInt::CC_GE;
570 return TypeInt::CC; // else use worst case results
571 }
572
573 // Simplify a CmpU (compare 2 integers) node, based on local information.
574 // If both inputs are constants, compare them.
575 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const {
576 assert(!t1->isa_ptr(), "obsolete usage of CmpU");
577
578 // comparing two unsigned ints
579 const TypeInt *r0 = t1->is_int(); // Handy access
580 const TypeInt *r1 = t2->is_int();
581
582 // Current installed version
583 // Compare ranges for non-overlap
584 juint lo0 = r0->_lo;
585 juint hi0 = r0->_hi;
586 juint lo1 = r1->_lo;
587 juint hi1 = r1->_hi;
588
589 // If either one has both negative and positive values,
590 // it therefore contains both 0 and -1, and since [0..-1] is the
591 // full unsigned range, the type must act as an unsigned bottom.
592 bool bot0 = ((jint)(lo0 ^ hi0) < 0);
593 bool bot1 = ((jint)(lo1 ^ hi1) < 0);
594
595 if (bot0 || bot1) {
596 // All unsigned values are LE -1 and GE 0.
597 if (lo0 == 0 && hi0 == 0) {
598 return TypeInt::CC_LE; // 0 <= bot
599 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) {
600 return TypeInt::CC_GE; // -1 >= bot
601 } else if (lo1 == 0 && hi1 == 0) {
602 return TypeInt::CC_GE; // bot >= 0
603 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) {
604 return TypeInt::CC_LE; // bot <= -1
605 }
606 } else {
607 // We can use ranges of the form [lo..hi] if signs are the same.
608 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
609 // results are reversed, '-' > '+' for unsigned compare
610 if (hi0 < lo1) {
611 return TypeInt::CC_LT; // smaller
612 } else if (lo0 > hi1) {
613 return TypeInt::CC_GT; // greater
614 } else if (hi0 == lo1 && lo0 == hi1) {
615 return TypeInt::CC_EQ; // Equal results
616 } else if (lo0 >= hi1) {
617 return TypeInt::CC_GE;
618 } else if (hi0 <= lo1) {
619 // Check for special case in Hashtable::get. (See below.)
620 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
621 return TypeInt::CC_LT;
622 return TypeInt::CC_LE;
623 }
624 }
625 // Check for special case in Hashtable::get - the hash index is
626 // mod'ed to the table size so the following range check is useless.
627 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have
628 // to be positive.
629 // (This is a gross hack, since the sub method never
630 // looks at the structure of the node in any other case.)
631 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
632 return TypeInt::CC_LT;
633 return TypeInt::CC; // else use worst case results
634 }
635
636 const Type* CmpUNode::Value(PhaseGVN* phase) const {
637 const Type* t = SubNode::Value_common(phase);
638 if (t != NULL) {
639 return t;
640 }
641 const Node* in1 = in(1);
642 const Node* in2 = in(2);
643 const Type* t1 = phase->type(in1);
644 const Type* t2 = phase->type(in2);
645 assert(t1->isa_int(), "CmpU has only Int type inputs");
646 if (t2 == TypeInt::INT) { // Compare to bottom?
647 return bottom_type();
648 }
649 uint in1_op = in1->Opcode();
650 if (in1_op == Op_AddI || in1_op == Op_SubI) {
651 // The problem rise when result of AddI(SubI) may overflow
652 // signed integer value. Let say the input type is
653 // [256, maxint] then +128 will create 2 ranges due to
654 // overflow: [minint, minint+127] and [384, maxint].
655 // But C2 type system keep only 1 type range and as result
656 // it use general [minint, maxint] for this case which we
657 // can't optimize.
658 //
659 // Make 2 separate type ranges based on types of AddI(SubI) inputs
660 // and compare results of their compare. If results are the same
661 // CmpU node can be optimized.
662 const Node* in11 = in1->in(1);
663 const Node* in12 = in1->in(2);
664 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11);
665 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12);
666 // Skip cases when input types are top or bottom.
667 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) &&
668 (t12 != Type::TOP) && (t12 != TypeInt::INT)) {
669 const TypeInt *r0 = t11->is_int();
670 const TypeInt *r1 = t12->is_int();
671 jlong lo_r0 = r0->_lo;
672 jlong hi_r0 = r0->_hi;
673 jlong lo_r1 = r1->_lo;
674 jlong hi_r1 = r1->_hi;
675 if (in1_op == Op_SubI) {
676 jlong tmp = hi_r1;
677 hi_r1 = -lo_r1;
678 lo_r1 = -tmp;
679 // Note, for substructing [minint,x] type range
680 // long arithmetic provides correct overflow answer.
681 // The confusion come from the fact that in 32-bit
682 // -minint == minint but in 64-bit -minint == maxint+1.
683 }
684 jlong lo_long = lo_r0 + lo_r1;
685 jlong hi_long = hi_r0 + hi_r1;
686 int lo_tr1 = min_jint;
687 int hi_tr1 = (int)hi_long;
688 int lo_tr2 = (int)lo_long;
689 int hi_tr2 = max_jint;
690 bool underflow = lo_long != (jlong)lo_tr2;
691 bool overflow = hi_long != (jlong)hi_tr1;
692 // Use sub(t1, t2) when there is no overflow (one type range)
693 // or when both overflow and underflow (too complex).
694 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) {
695 // Overflow only on one boundary, compare 2 separate type ranges.
696 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
697 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w);
698 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w);
699 const Type* cmp1 = sub(tr1, t2);
700 const Type* cmp2 = sub(tr2, t2);
701 if (cmp1 == cmp2) {
702 return cmp1; // Hit!
703 }
704 }
705 }
706 }
707
708 return sub(t1, t2); // Local flavor of type subtraction
709 }
710
711 bool CmpUNode::is_index_range_check() const {
712 // Check for the "(X ModI Y) CmpU Y" shape
713 return (in(1)->Opcode() == Op_ModI &&
714 in(1)->in(2)->eqv_uncast(in(2)));
715 }
716
717 //------------------------------Idealize---------------------------------------
718 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
719 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) {
720 switch (in(1)->Opcode()) {
721 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL
722 return new CmpLNode(in(1)->in(1),in(1)->in(2));
723 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF
724 return new CmpFNode(in(1)->in(1),in(1)->in(2));
725 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD
726 return new CmpDNode(in(1)->in(1),in(1)->in(2));
727 //case Op_SubI:
728 // If (x - y) cannot overflow, then ((x - y) <?> 0)
729 // can be turned into (x <?> y).
730 // This is handled (with more general cases) by Ideal_sub_algebra.
731 }
732 }
733 return NULL; // No change
734 }
735
736
737 //=============================================================================
738 // Simplify a CmpL (compare 2 longs ) node, based on local information.
739 // If both inputs are constants, compare them.
740 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const {
741 const TypeLong *r0 = t1->is_long(); // Handy access
742 const TypeLong *r1 = t2->is_long();
743
744 if( r0->_hi < r1->_lo ) // Range is always low?
745 return TypeInt::CC_LT;
746 else if( r0->_lo > r1->_hi ) // Range is always high?
747 return TypeInt::CC_GT;
748
749 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
750 assert(r0->get_con() == r1->get_con(), "must be equal");
751 return TypeInt::CC_EQ; // Equal results.
752 } else if( r0->_hi == r1->_lo ) // Range is never high?
753 return TypeInt::CC_LE;
754 else if( r0->_lo == r1->_hi ) // Range is never low?
755 return TypeInt::CC_GE;
756 return TypeInt::CC; // else use worst case results
757 }
758
759
760 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information.
761 // If both inputs are constants, compare them.
762 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const {
763 assert(!t1->isa_ptr(), "obsolete usage of CmpUL");
764
765 // comparing two unsigned longs
766 const TypeLong* r0 = t1->is_long(); // Handy access
767 const TypeLong* r1 = t2->is_long();
768
769 // Current installed version
770 // Compare ranges for non-overlap
771 julong lo0 = r0->_lo;
772 julong hi0 = r0->_hi;
773 julong lo1 = r1->_lo;
774 julong hi1 = r1->_hi;
775
776 // If either one has both negative and positive values,
777 // it therefore contains both 0 and -1, and since [0..-1] is the
778 // full unsigned range, the type must act as an unsigned bottom.
779 bool bot0 = ((jlong)(lo0 ^ hi0) < 0);
780 bool bot1 = ((jlong)(lo1 ^ hi1) < 0);
781
782 if (bot0 || bot1) {
783 // All unsigned values are LE -1 and GE 0.
784 if (lo0 == 0 && hi0 == 0) {
785 return TypeInt::CC_LE; // 0 <= bot
786 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) {
787 return TypeInt::CC_GE; // -1 >= bot
788 } else if (lo1 == 0 && hi1 == 0) {
789 return TypeInt::CC_GE; // bot >= 0
790 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) {
791 return TypeInt::CC_LE; // bot <= -1
792 }
793 } else {
794 // We can use ranges of the form [lo..hi] if signs are the same.
795 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
796 // results are reversed, '-' > '+' for unsigned compare
797 if (hi0 < lo1) {
798 return TypeInt::CC_LT; // smaller
799 } else if (lo0 > hi1) {
800 return TypeInt::CC_GT; // greater
801 } else if (hi0 == lo1 && lo0 == hi1) {
802 return TypeInt::CC_EQ; // Equal results
803 } else if (lo0 >= hi1) {
804 return TypeInt::CC_GE;
805 } else if (hi0 <= lo1) {
806 return TypeInt::CC_LE;
807 }
808 }
809
810 return TypeInt::CC; // else use worst case results
811 }
812
813 //=============================================================================
814 //------------------------------sub--------------------------------------------
815 // Simplify an CmpP (compare 2 pointers) node, based on local information.
816 // If both inputs are constants, compare them.
817 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const {
818 const TypePtr *r0 = t1->is_ptr(); // Handy access
819 const TypePtr *r1 = t2->is_ptr();
820
821 // Undefined inputs makes for an undefined result
822 if( TypePtr::above_centerline(r0->_ptr) ||
823 TypePtr::above_centerline(r1->_ptr) )
824 return Type::TOP;
825
826 if (r0 == r1 && r0->singleton()) {
827 // Equal pointer constants (klasses, nulls, etc.)
828 return TypeInt::CC_EQ;
829 }
830
831 // See if it is 2 unrelated classes.
832 const TypeOopPtr* p0 = r0->isa_oopptr();
833 const TypeOopPtr* p1 = r1->isa_oopptr();
834 if (p0 && p1) {
835 Node* in1 = in(1)->uncast();
836 Node* in2 = in(2)->uncast();
837 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1, NULL);
838 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2, NULL);
839 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, NULL)) {
840 return TypeInt::CC_GT; // different pointers
841 }
842 ciKlass* klass0 = p0->klass();
843 bool xklass0 = p0->klass_is_exact();
844 ciKlass* klass1 = p1->klass();
845 bool xklass1 = p1->klass_is_exact();
846 int kps = (p0->isa_klassptr()?1:0) + (p1->isa_klassptr()?1:0);
847 if (klass0 && klass1 &&
848 kps != 1 && // both or neither are klass pointers
849 klass0->is_loaded() && !klass0->is_interface() && // do not trust interfaces
850 klass1->is_loaded() && !klass1->is_interface() &&
851 (!klass0->is_obj_array_klass() ||
852 !klass0->as_obj_array_klass()->base_element_klass()->is_interface()) &&
853 (!klass1->is_obj_array_klass() ||
854 !klass1->as_obj_array_klass()->base_element_klass()->is_interface())) {
855 bool unrelated_classes = false;
856 // See if neither subclasses the other, or if the class on top
857 // is precise. In either of these cases, the compare is known
858 // to fail if at least one of the pointers is provably not null.
859 if (klass0->equals(klass1)) { // if types are unequal but klasses are equal
860 // Do nothing; we know nothing for imprecise types
861 } else if (klass0->is_subtype_of(klass1)) {
862 // If klass1's type is PRECISE, then classes are unrelated.
863 unrelated_classes = xklass1;
864 } else if (klass1->is_subtype_of(klass0)) {
865 // If klass0's type is PRECISE, then classes are unrelated.
866 unrelated_classes = xklass0;
867 } else { // Neither subtypes the other
868 unrelated_classes = true;
869 }
870 if (unrelated_classes) {
871 // The oops classes are known to be unrelated. If the joined PTRs of
872 // two oops is not Null and not Bottom, then we are sure that one
873 // of the two oops is non-null, and the comparison will always fail.
874 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
875 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
876 return TypeInt::CC_GT;
877 }
878 }
879 }
880 }
881
882 // Known constants can be compared exactly
883 // Null can be distinguished from any NotNull pointers
884 // Unknown inputs makes an unknown result
885 if( r0->singleton() ) {
886 intptr_t bits0 = r0->get_con();
887 if( r1->singleton() )
888 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
889 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
890 } else if( r1->singleton() ) {
891 intptr_t bits1 = r1->get_con();
892 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
893 } else
894 return TypeInt::CC;
895 }
896
897 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) {
898 // Return the klass node for (indirect load from OopHandle)
899 // LoadP(LoadP(AddP(foo:Klass, #java_mirror)))
900 // or NULL if not matching.
901
902 #if INCLUDE_SHENANDOAHGC
903 n = ShenandoahBarrierNode::skip_through_barrier(n);
904 #endif
905
906 if (n->Opcode() != Op_LoadP) return NULL;
907
908 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
909 if (!tp || tp->klass() != phase->C->env()->Class_klass()) return NULL;
910
911 Node* adr = n->in(MemNode::Address);
912 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier.
913 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return NULL;
914 adr = adr->in(MemNode::Address);
915
916 intptr_t off = 0;
917 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off);
918 if (k == NULL) return NULL;
919 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr();
920 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return NULL;
921
922 // We've found the klass node of a Java mirror load.
923 return k;
924 }
925
926 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) {
927 // for ConP(Foo.class) return ConP(Foo.klass)
928 // otherwise return NULL
929 if (!n->is_Con()) return NULL;
930
931 const TypeInstPtr* tp = phase->type(n)->isa_instptr();
932 if (!tp) return NULL;
933
934 ciType* mirror_type = tp->java_mirror_type();
935 // TypeInstPtr::java_mirror_type() returns non-NULL for compile-
936 // time Class constants only.
937 if (!mirror_type) return NULL;
938
939 // x.getClass() == int.class can never be true (for all primitive types)
940 // Return a ConP(NULL) node for this case.
941 if (mirror_type->is_classless()) {
942 return phase->makecon(TypePtr::NULL_PTR);
943 }
944
945 // return the ConP(Foo.klass)
946 assert(mirror_type->is_klass(), "mirror_type should represent a Klass*");
947 return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass()));
948 }
949
950 //------------------------------Ideal------------------------------------------
951 // Normalize comparisons between Java mirror loads to compare the klass instead.
952 //
953 // Also check for the case of comparing an unknown klass loaded from the primary
954 // super-type array vs a known klass with no subtypes. This amounts to
955 // checking to see an unknown klass subtypes a known klass with no subtypes;
956 // this only happens on an exact match. We can shorten this test by 1 load.
957 Node *CmpPNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
958 #if INCLUDE_SHENANDOAHGC
959 if (UseShenandoahGC) {
960 Node* in1 = in(1);
961 Node* in2 = in(2);
962 if (in1->bottom_type() == TypePtr::NULL_PTR) {
963 in2 = ShenandoahBarrierNode::skip_through_barrier(in2);
964 }
965 if (in2->bottom_type() == TypePtr::NULL_PTR) {
966 in1 = ShenandoahBarrierNode::skip_through_barrier(in1);
967 }
968 PhaseIterGVN* igvn = phase->is_IterGVN();
969 if (in1 != in(1)) {
970 if (igvn != NULL) {
971 set_req_X(1, in1, igvn);
972 } else {
973 set_req(1, in1);
974 }
975 assert(in2 == in(2), "only one change");
976 return this;
977 }
978 if (in2 != in(2)) {
979 if (igvn != NULL) {
980 set_req_X(2, in2, igvn);
981 } else {
982 set_req(2, in2);
983 }
984 return this;
985 }
986 }
987 #endif
988
989 // Normalize comparisons between Java mirrors into comparisons of the low-
990 // level klass, where a dependent load could be shortened.
991 //
992 // The new pattern has a nice effect of matching the same pattern used in the
993 // fast path of instanceof/checkcast/Class.isInstance(), which allows
994 // redundant exact type check be optimized away by GVN.
995 // For example, in
996 // if (x.getClass() == Foo.class) {
997 // Foo foo = (Foo) x;
998 // // ... use a ...
999 // }
1000 // a CmpPNode could be shared between if_acmpne and checkcast
1001 {
1002 Node* k1 = isa_java_mirror_load(phase, in(1));
1003 Node* k2 = isa_java_mirror_load(phase, in(2));
1004 Node* conk2 = isa_const_java_mirror(phase, in(2));
1005
1006 if (k1 && (k2 || conk2)) {
1007 Node* lhs = k1;
1008 Node* rhs = (k2 != NULL) ? k2 : conk2;
1009 this->set_req(1, lhs);
1010 this->set_req(2, rhs);
1011 return this;
1012 }
1013 }
1014
1015 // Constant pointer on right?
1016 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
1017 if (t2 == NULL || !t2->klass_is_exact())
1018 return NULL;
1019 // Get the constant klass we are comparing to.
1020 ciKlass* superklass = t2->klass();
1021
1022 // Now check for LoadKlass on left.
1023 Node* ldk1 = in(1);
1024 if (ldk1->is_DecodeNKlass()) {
1025 ldk1 = ldk1->in(1);
1026 if (ldk1->Opcode() != Op_LoadNKlass )
1027 return NULL;
1028 } else if (ldk1->Opcode() != Op_LoadKlass )
1029 return NULL;
1030 // Take apart the address of the LoadKlass:
1031 Node* adr1 = ldk1->in(MemNode::Address);
1032 intptr_t con2 = 0;
1033 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
1034 if (ldk2 == NULL)
1035 return NULL;
1036 if (con2 == oopDesc::klass_offset_in_bytes()) {
1037 // We are inspecting an object's concrete class.
1038 // Short-circuit the check if the query is abstract.
1039 if (superklass->is_interface() ||
1040 superklass->is_abstract()) {
1041 // Make it come out always false:
1042 this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
1043 return this;
1044 }
1045 }
1046
1047 // Check for a LoadKlass from primary supertype array.
1048 // Any nested loadklass from loadklass+con must be from the p.s. array.
1049 if (ldk2->is_DecodeNKlass()) {
1050 // Keep ldk2 as DecodeN since it could be used in CmpP below.
1051 if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
1052 return NULL;
1053 } else if (ldk2->Opcode() != Op_LoadKlass)
1054 return NULL;
1055
1056 // Verify that we understand the situation
1057 if (con2 != (intptr_t) superklass->super_check_offset())
1058 return NULL; // Might be element-klass loading from array klass
1059
1060 // If 'superklass' has no subklasses and is not an interface, then we are
1061 // assured that the only input which will pass the type check is
1062 // 'superklass' itself.
1063 //
1064 // We could be more liberal here, and allow the optimization on interfaces
1065 // which have a single implementor. This would require us to increase the
1066 // expressiveness of the add_dependency() mechanism.
1067 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now.
1068
1069 // Object arrays must have their base element have no subtypes
1070 while (superklass->is_obj_array_klass()) {
1071 ciType* elem = superklass->as_obj_array_klass()->element_type();
1072 superklass = elem->as_klass();
1073 }
1074 if (superklass->is_instance_klass()) {
1075 ciInstanceKlass* ik = superklass->as_instance_klass();
1076 if (ik->has_subklass() || ik->is_interface()) return NULL;
1077 // Add a dependency if there is a chance that a subclass will be added later.
1078 if (!ik->is_final()) {
1079 phase->C->dependencies()->assert_leaf_type(ik);
1080 }
1081 }
1082
1083 // Bypass the dependent load, and compare directly
1084 this->set_req(1,ldk2);
1085
1086 return this;
1087 }
1088
1089 //=============================================================================
1090 //------------------------------sub--------------------------------------------
1091 // Simplify an CmpN (compare 2 pointers) node, based on local information.
1092 // If both inputs are constants, compare them.
1093 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
1094 const TypePtr *r0 = t1->make_ptr(); // Handy access
1095 const TypePtr *r1 = t2->make_ptr();
1096
1097 // Undefined inputs makes for an undefined result
1098 if ((r0 == NULL) || (r1 == NULL) ||
1099 TypePtr::above_centerline(r0->_ptr) ||
1100 TypePtr::above_centerline(r1->_ptr)) {
1101 return Type::TOP;
1102 }
1103 if (r0 == r1 && r0->singleton()) {
1104 // Equal pointer constants (klasses, nulls, etc.)
1105 return TypeInt::CC_EQ;
1106 }
1107
1108 // See if it is 2 unrelated classes.
1109 const TypeOopPtr* p0 = r0->isa_oopptr();
1110 const TypeOopPtr* p1 = r1->isa_oopptr();
1111 if (p0 && p1) {
1112 ciKlass* klass0 = p0->klass();
1113 bool xklass0 = p0->klass_is_exact();
1114 ciKlass* klass1 = p1->klass();
1115 bool xklass1 = p1->klass_is_exact();
1116 int kps = (p0->isa_klassptr()?1:0) + (p1->isa_klassptr()?1:0);
1117 if (klass0 && klass1 &&
1118 kps != 1 && // both or neither are klass pointers
1119 !klass0->is_interface() && // do not trust interfaces
1120 !klass1->is_interface()) {
1121 bool unrelated_classes = false;
1122 // See if neither subclasses the other, or if the class on top
1123 // is precise. In either of these cases, the compare is known
1124 // to fail if at least one of the pointers is provably not null.
1125 if (klass0->equals(klass1)) { // if types are unequal but klasses are equal
1126 // Do nothing; we know nothing for imprecise types
1127 } else if (klass0->is_subtype_of(klass1)) {
1128 // If klass1's type is PRECISE, then classes are unrelated.
1129 unrelated_classes = xklass1;
1130 } else if (klass1->is_subtype_of(klass0)) {
1131 // If klass0's type is PRECISE, then classes are unrelated.
1132 unrelated_classes = xklass0;
1133 } else { // Neither subtypes the other
1134 unrelated_classes = true;
1135 }
1136 if (unrelated_classes) {
1137 // The oops classes are known to be unrelated. If the joined PTRs of
1138 // two oops is not Null and not Bottom, then we are sure that one
1139 // of the two oops is non-null, and the comparison will always fail.
1140 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
1141 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
1142 return TypeInt::CC_GT;
1143 }
1144 }
1145 }
1146 }
1147
1148 // Known constants can be compared exactly
1149 // Null can be distinguished from any NotNull pointers
1150 // Unknown inputs makes an unknown result
1151 if( r0->singleton() ) {
1152 intptr_t bits0 = r0->get_con();
1153 if( r1->singleton() )
1154 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
1155 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1156 } else if( r1->singleton() ) {
1157 intptr_t bits1 = r1->get_con();
1158 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1159 } else
1160 return TypeInt::CC;
1161 }
1162
1163 //------------------------------Ideal------------------------------------------
1164 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1165 return NULL;
1166 }
1167
1168 //=============================================================================
1169 //------------------------------Value------------------------------------------
1170 // Simplify an CmpF (compare 2 floats ) node, based on local information.
1171 // If both inputs are constants, compare them.
1172 const Type* CmpFNode::Value(PhaseGVN* phase) const {
1173 const Node* in1 = in(1);
1174 const Node* in2 = in(2);
1175 // Either input is TOP ==> the result is TOP
1176 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1177 if( t1 == Type::TOP ) return Type::TOP;
1178 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1179 if( t2 == Type::TOP ) return Type::TOP;
1180
1181 // Not constants? Don't know squat - even if they are the same
1182 // value! If they are NaN's they compare to LT instead of EQ.
1183 const TypeF *tf1 = t1->isa_float_constant();
1184 const TypeF *tf2 = t2->isa_float_constant();
1185 if( !tf1 || !tf2 ) return TypeInt::CC;
1186
1187 // This implements the Java bytecode fcmpl, so unordered returns -1.
1188 if( tf1->is_nan() || tf2->is_nan() )
1189 return TypeInt::CC_LT;
1190
1191 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
1192 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
1193 assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
1194 return TypeInt::CC_EQ;
1195 }
1196
1197
1198 //=============================================================================
1199 //------------------------------Value------------------------------------------
1200 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
1201 // If both inputs are constants, compare them.
1202 const Type* CmpDNode::Value(PhaseGVN* phase) const {
1203 const Node* in1 = in(1);
1204 const Node* in2 = in(2);
1205 // Either input is TOP ==> the result is TOP
1206 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1207 if( t1 == Type::TOP ) return Type::TOP;
1208 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1209 if( t2 == Type::TOP ) return Type::TOP;
1210
1211 // Not constants? Don't know squat - even if they are the same
1212 // value! If they are NaN's they compare to LT instead of EQ.
1213 const TypeD *td1 = t1->isa_double_constant();
1214 const TypeD *td2 = t2->isa_double_constant();
1215 if( !td1 || !td2 ) return TypeInt::CC;
1216
1217 // This implements the Java bytecode dcmpl, so unordered returns -1.
1218 if( td1->is_nan() || td2->is_nan() )
1219 return TypeInt::CC_LT;
1220
1221 if( td1->_d < td2->_d ) return TypeInt::CC_LT;
1222 if( td1->_d > td2->_d ) return TypeInt::CC_GT;
1223 assert( td1->_d == td2->_d, "do not understand FP behavior" );
1224 return TypeInt::CC_EQ;
1225 }
1226
1227 //------------------------------Ideal------------------------------------------
1228 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
1229 // Check if we can change this to a CmpF and remove a ConvD2F operation.
1230 // Change (CMPD (F2D (float)) (ConD value))
1231 // To (CMPF (float) (ConF value))
1232 // Valid when 'value' does not lose precision as a float.
1233 // Benefits: eliminates conversion, does not require 24-bit mode
1234
1235 // NaNs prevent commuting operands. This transform works regardless of the
1236 // order of ConD and ConvF2D inputs by preserving the original order.
1237 int idx_f2d = 1; // ConvF2D on left side?
1238 if( in(idx_f2d)->Opcode() != Op_ConvF2D )
1239 idx_f2d = 2; // No, swap to check for reversed args
1240 int idx_con = 3-idx_f2d; // Check for the constant on other input
1241
1242 if( ConvertCmpD2CmpF &&
1243 in(idx_f2d)->Opcode() == Op_ConvF2D &&
1244 in(idx_con)->Opcode() == Op_ConD ) {
1245 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
1246 double t2_value_as_double = t2->_d;
1247 float t2_value_as_float = (float)t2_value_as_double;
1248 if( t2_value_as_double == (double)t2_value_as_float ) {
1249 // Test value can be represented as a float
1250 // Eliminate the conversion to double and create new comparison
1251 Node *new_in1 = in(idx_f2d)->in(1);
1252 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
1253 if( idx_f2d != 1 ) { // Must flip args to match original order
1254 Node *tmp = new_in1;
1255 new_in1 = new_in2;
1256 new_in2 = tmp;
1257 }
1258 CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
1259 ? new CmpF3Node( new_in1, new_in2 )
1260 : new CmpFNode ( new_in1, new_in2 ) ;
1261 return new_cmp; // Changed to CmpFNode
1262 }
1263 // Testing value required the precision of a double
1264 }
1265 return NULL; // No change
1266 }
1267
1268
1269 //=============================================================================
1270 //------------------------------cc2logical-------------------------------------
1271 // Convert a condition code type to a logical type
1272 const Type *BoolTest::cc2logical( const Type *CC ) const {
1273 if( CC == Type::TOP ) return Type::TOP;
1274 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
1275 const TypeInt *ti = CC->is_int();
1276 if( ti->is_con() ) { // Only 1 kind of condition codes set?
1277 // Match low order 2 bits
1278 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
1279 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result
1280 return TypeInt::make(tmp); // Boolean result
1281 }
1282
1283 if( CC == TypeInt::CC_GE ) {
1284 if( _test == ge ) return TypeInt::ONE;
1285 if( _test == lt ) return TypeInt::ZERO;
1286 }
1287 if( CC == TypeInt::CC_LE ) {
1288 if( _test == le ) return TypeInt::ONE;
1289 if( _test == gt ) return TypeInt::ZERO;
1290 }
1291
1292 return TypeInt::BOOL;
1293 }
1294
1295 //------------------------------dump_spec-------------------------------------
1296 // Print special per-node info
1297 void BoolTest::dump_on(outputStream *st) const {
1298 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"};
1299 st->print("%s", msg[_test]);
1300 }
1301
1302 //=============================================================================
1303 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
1304 uint BoolNode::size_of() const { return sizeof(BoolNode); }
1305
1306 //------------------------------operator==-------------------------------------
1307 uint BoolNode::cmp( const Node &n ) const {
1308 const BoolNode *b = (const BoolNode *)&n; // Cast up
1309 return (_test._test == b->_test._test);
1310 }
1311
1312 //-------------------------------make_predicate--------------------------------
1313 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1314 if (test_value->is_Con()) return test_value;
1315 if (test_value->is_Bool()) return test_value;
1316 if (test_value->is_CMove() &&
1317 test_value->in(CMoveNode::Condition)->is_Bool()) {
1318 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool();
1319 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1320 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1321 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1322 return bol;
1323 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1324 return phase->transform( bol->negate(phase) );
1325 }
1326 // Else fall through. The CMove gets in the way of the test.
1327 // It should be the case that make_predicate(bol->as_int_value()) == bol.
1328 }
1329 Node* cmp = new CmpINode(test_value, phase->intcon(0));
1330 cmp = phase->transform(cmp);
1331 Node* bol = new BoolNode(cmp, BoolTest::ne);
1332 return phase->transform(bol);
1333 }
1334
1335 //--------------------------------as_int_value---------------------------------
1336 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1337 // Inverse to make_predicate. The CMove probably boils down to a Conv2B.
1338 Node* cmov = CMoveNode::make(NULL, this,
1339 phase->intcon(0), phase->intcon(1),
1340 TypeInt::BOOL);
1341 return phase->transform(cmov);
1342 }
1343
1344 //----------------------------------negate-------------------------------------
1345 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1346 return new BoolNode(in(1), _test.negate());
1347 }
1348
1349 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub
1350 // overflows and we can prove that C is not in the two resulting ranges.
1351 // This optimization is similar to the one performed by CmpUNode::Value().
1352 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op,
1353 int cmp1_op, const TypeInt* cmp2_type) {
1354 // Only optimize eq/ne integer comparison of add/sub
1355 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1356 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) {
1357 // Skip cases were inputs of add/sub are not integers or of bottom type
1358 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int();
1359 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int();
1360 if ((r0 != NULL) && (r0 != TypeInt::INT) &&
1361 (r1 != NULL) && (r1 != TypeInt::INT) &&
1362 (cmp2_type != TypeInt::INT)) {
1363 // Compute exact (long) type range of add/sub result
1364 jlong lo_long = r0->_lo;
1365 jlong hi_long = r0->_hi;
1366 if (cmp1_op == Op_AddI) {
1367 lo_long += r1->_lo;
1368 hi_long += r1->_hi;
1369 } else {
1370 lo_long -= r1->_hi;
1371 hi_long -= r1->_lo;
1372 }
1373 // Check for over-/underflow by casting to integer
1374 int lo_int = (int)lo_long;
1375 int hi_int = (int)hi_long;
1376 bool underflow = lo_long != (jlong)lo_int;
1377 bool overflow = hi_long != (jlong)hi_int;
1378 if ((underflow != overflow) && (hi_int < lo_int)) {
1379 // Overflow on one boundary, compute resulting type ranges:
1380 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT]
1381 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
1382 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w);
1383 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w);
1384 // Compare second input of cmp to both type ranges
1385 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type);
1386 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type);
1387 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) {
1388 // The result of the add/sub will never equal cmp2. Replace BoolNode
1389 // by false (0) if it tests for equality and by true (1) otherwise.
1390 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1);
1391 }
1392 }
1393 }
1394 }
1395 return NULL;
1396 }
1397
1398 //------------------------------Ideal------------------------------------------
1399 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1400 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1401 // This moves the constant to the right. Helps value-numbering.
1402 Node *cmp = in(1);
1403 if( !cmp->is_Sub() ) return NULL;
1404 int cop = cmp->Opcode();
1405 if( cop == Op_FastLock || cop == Op_FastUnlock) return NULL;
1406 Node *cmp1 = cmp->in(1);
1407 Node *cmp2 = cmp->in(2);
1408 if( !cmp1 ) return NULL;
1409
1410 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) {
1411 return NULL;
1412 }
1413
1414 // Constant on left?
1415 Node *con = cmp1;
1416 uint op2 = cmp2->Opcode();
1417 // Move constants to the right of compare's to canonicalize.
1418 // Do not muck with Opaque1 nodes, as this indicates a loop
1419 // guard that cannot change shape.
1420 if( con->is_Con() && !cmp2->is_Con() && op2 != Op_Opaque1 &&
1421 // Because of NaN's, CmpD and CmpF are not commutative
1422 cop != Op_CmpD && cop != Op_CmpF &&
1423 // Protect against swapping inputs to a compare when it is used by a
1424 // counted loop exit, which requires maintaining the loop-limit as in(2)
1425 !is_counted_loop_exit_test() ) {
1426 // Ok, commute the constant to the right of the cmp node.
1427 // Clone the Node, getting a new Node of the same class
1428 cmp = cmp->clone();
1429 // Swap inputs to the clone
1430 cmp->swap_edges(1, 2);
1431 cmp = phase->transform( cmp );
1432 return new BoolNode( cmp, _test.commute() );
1433 }
1434
1435 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1436 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the
1437 // test instead.
1438 int cmp1_op = cmp1->Opcode();
1439 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1440 if (cmp2_type == NULL) return NULL;
1441 Node* j_xor = cmp1;
1442 if( cmp2_type == TypeInt::ZERO &&
1443 cmp1_op == Op_XorI &&
1444 j_xor->in(1) != j_xor && // An xor of itself is dead
1445 phase->type( j_xor->in(1) ) == TypeInt::BOOL &&
1446 phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1447 (_test._test == BoolTest::eq ||
1448 _test._test == BoolTest::ne) ) {
1449 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2));
1450 return new BoolNode( ncmp, _test.negate() );
1451 }
1452
1453 // Change ((x & m) u<= m) or ((m & x) u<= m) to always true
1454 // Same with ((x & m) u< m+1) and ((m & x) u< m+1)
1455 if (cop == Op_CmpU &&
1456 cmp1->Opcode() == Op_AndI) {
1457 Node* bound = NULL;
1458 if (_test._test == BoolTest::le) {
1459 bound = cmp2;
1460 } else if (_test._test == BoolTest::lt &&
1461 cmp2->Opcode() == Op_AddI &&
1462 cmp2->in(2)->find_int_con(0) == 1) {
1463 bound = cmp2->in(1);
1464 }
1465 if (cmp1->in(2) == bound || cmp1->in(1) == bound) {
1466 return ConINode::make(1);
1467 }
1468 }
1469
1470 // Change ((x & (m - 1)) u< m) into (m > 0)
1471 // This is the off-by-one variant of the above
1472 if (cop == Op_CmpU &&
1473 _test._test == BoolTest::lt &&
1474 cmp1->Opcode() == Op_AndI) {
1475 Node* l = cmp1->in(1);
1476 Node* r = cmp1->in(2);
1477 for (int repeat = 0; repeat < 2; repeat++) {
1478 bool match = r->Opcode() == Op_AddI && r->in(2)->find_int_con(0) == -1 &&
1479 r->in(1) == cmp2;
1480 if (match) {
1481 // arraylength known to be non-negative, so a (arraylength != 0) is sufficient,
1482 // but to be compatible with the array range check pattern, use (arraylength u> 0)
1483 Node* ncmp = cmp2->Opcode() == Op_LoadRange
1484 ? phase->transform(new CmpUNode(cmp2, phase->intcon(0)))
1485 : phase->transform(new CmpINode(cmp2, phase->intcon(0)));
1486 return new BoolNode(ncmp, BoolTest::gt);
1487 } else {
1488 // commute and try again
1489 l = cmp1->in(2);
1490 r = cmp1->in(1);
1491 }
1492 }
1493 }
1494
1495 // Change (arraylength <= 0) or (arraylength == 0)
1496 // into (arraylength u<= 0)
1497 // Also change (arraylength != 0) into (arraylength u> 0)
1498 // The latter version matches the code pattern generated for
1499 // array range checks, which will more likely be optimized later.
1500 if (cop == Op_CmpI &&
1501 cmp1->Opcode() == Op_LoadRange &&
1502 cmp2->find_int_con(-1) == 0) {
1503 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) {
1504 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1505 return new BoolNode(ncmp, BoolTest::le);
1506 } else if (_test._test == BoolTest::ne) {
1507 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1508 return new BoolNode(ncmp, BoolTest::gt);
1509 }
1510 }
1511
1512 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1513 // This is a standard idiom for branching on a boolean value.
1514 Node *c2b = cmp1;
1515 if( cmp2_type == TypeInt::ZERO &&
1516 cmp1_op == Op_Conv2B &&
1517 (_test._test == BoolTest::eq ||
1518 _test._test == BoolTest::ne) ) {
1519 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1520 ? (Node*)new CmpINode(c2b->in(1),cmp2)
1521 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1522 );
1523 return new BoolNode( ncmp, _test._test );
1524 }
1525
1526 // Comparing a SubI against a zero is equal to comparing the SubI
1527 // arguments directly. This only works for eq and ne comparisons
1528 // due to possible integer overflow.
1529 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1530 (cop == Op_CmpI) &&
1531 (cmp1->Opcode() == Op_SubI) &&
1532 ( cmp2_type == TypeInt::ZERO ) ) {
1533 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2)));
1534 return new BoolNode( ncmp, _test._test );
1535 }
1536
1537 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the
1538 // most general case because negating 0x80000000 does nothing. Needed for
1539 // the CmpF3/SubI/CmpI idiom.
1540 if( cop == Op_CmpI &&
1541 cmp1->Opcode() == Op_SubI &&
1542 cmp2_type == TypeInt::ZERO &&
1543 phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1544 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1545 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2));
1546 return new BoolNode( ncmp, _test.commute() );
1547 }
1548
1549 // Try to optimize signed integer comparison
1550 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type);
1551
1552 // The transformation below is not valid for either signed or unsigned
1553 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1554 // This transformation can be resurrected when we are able to
1555 // make inferences about the range of values being subtracted from
1556 // (or added to) relative to the wraparound point.
1557 //
1558 // // Remove +/-1's if possible.
1559 // // "X <= Y-1" becomes "X < Y"
1560 // // "X+1 <= Y" becomes "X < Y"
1561 // // "X < Y+1" becomes "X <= Y"
1562 // // "X-1 < Y" becomes "X <= Y"
1563 // // Do not this to compares off of the counted-loop-end. These guys are
1564 // // checking the trip counter and they want to use the post-incremented
1565 // // counter. If they use the PRE-incremented counter, then the counter has
1566 // // to be incremented in a private block on a loop backedge.
1567 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1568 // return NULL;
1569 // #ifndef PRODUCT
1570 // // Do not do this in a wash GVN pass during verification.
1571 // // Gets triggered by too many simple optimizations to be bothered with
1572 // // re-trying it again and again.
1573 // if( !phase->allow_progress() ) return NULL;
1574 // #endif
1575 // // Not valid for unsigned compare because of corner cases in involving zero.
1576 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1577 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1578 // // "0 <=u Y" is always true).
1579 // if( cmp->Opcode() == Op_CmpU ) return NULL;
1580 // int cmp2_op = cmp2->Opcode();
1581 // if( _test._test == BoolTest::le ) {
1582 // if( cmp1_op == Op_AddI &&
1583 // phase->type( cmp1->in(2) ) == TypeInt::ONE )
1584 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1585 // else if( cmp2_op == Op_AddI &&
1586 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1587 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1588 // } else if( _test._test == BoolTest::lt ) {
1589 // if( cmp1_op == Op_AddI &&
1590 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1591 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1592 // else if( cmp2_op == Op_AddI &&
1593 // phase->type( cmp2->in(2) ) == TypeInt::ONE )
1594 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1595 // }
1596 }
1597
1598 //------------------------------Value------------------------------------------
1599 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
1600 // based on local information. If the input is constant, do it.
1601 const Type* BoolNode::Value(PhaseGVN* phase) const {
1602 return _test.cc2logical( phase->type( in(1) ) );
1603 }
1604
1605 #ifndef PRODUCT
1606 //------------------------------dump_spec--------------------------------------
1607 // Dump special per-node info
1608 void BoolNode::dump_spec(outputStream *st) const {
1609 st->print("[");
1610 _test.dump_on(st);
1611 st->print("]");
1612 }
1613
1614 //-------------------------------related---------------------------------------
1615 // A BoolNode's related nodes are all of its data inputs, and all of its
1616 // outputs until control nodes are hit, which are included. In compact
1617 // representation, inputs till level 3 and immediate outputs are included.
1618 void BoolNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
1619 if (compact) {
1620 this->collect_nodes(in_rel, 3, false, true);
1621 this->collect_nodes(out_rel, -1, false, false);
1622 } else {
1623 this->collect_nodes_in_all_data(in_rel, false);
1624 this->collect_nodes_out_all_ctrl_boundary(out_rel);
1625 }
1626 }
1627 #endif
1628
1629 //----------------------is_counted_loop_exit_test------------------------------
1630 // Returns true if node is used by a counted loop node.
1631 bool BoolNode::is_counted_loop_exit_test() {
1632 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
1633 Node* use = fast_out(i);
1634 if (use->is_CountedLoopEnd()) {
1635 return true;
1636 }
1637 }
1638 return false;
1639 }
1640
1641 //=============================================================================
1642 //------------------------------Value------------------------------------------
1643 // Compute sqrt
1644 const Type* SqrtDNode::Value(PhaseGVN* phase) const {
1645 const Type *t1 = phase->type( in(1) );
1646 if( t1 == Type::TOP ) return Type::TOP;
1647 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1648 double d = t1->getd();
1649 if( d < 0.0 ) return Type::DOUBLE;
1650 return TypeD::make( sqrt( d ) );
1651 }
1652
1653 const Type* SqrtFNode::Value(PhaseGVN* phase) const {
1654 const Type *t1 = phase->type( in(1) );
1655 if( t1 == Type::TOP ) return Type::TOP;
1656 if( t1->base() != Type::FloatCon ) return Type::FLOAT;
1657 float f = t1->getf();
1658 if( f < 0.0f ) return Type::FLOAT;
1659 return TypeF::make( (float)sqrt( (double)f ) );
1660 }