1 /*
2 * Copyright 1997-2008 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 // Portions of code courtesy of Clifford Click
26
27 // Optimization - Graph Style
28
29 #include "incls/_precompiled.incl"
30 #include "incls/_subnode.cpp.incl"
31 #include "math.h"
32
33 //=============================================================================
34 //------------------------------Identity---------------------------------------
35 // If right input is a constant 0, return the left input.
36 Node *SubNode::Identity( PhaseTransform *phase ) {
37 assert(in(1) != this, "Must already have called Value");
38 assert(in(2) != this, "Must already have called Value");
39
40 // Remove double negation
41 const Type *zero = add_id();
42 if( phase->type( in(1) )->higher_equal( zero ) &&
43 in(2)->Opcode() == Opcode() &&
44 phase->type( in(2)->in(1) )->higher_equal( zero ) ) {
45 return in(2)->in(2);
46 }
47
48 // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y
49 if( in(1)->Opcode() == Op_AddI ) {
50 if( phase->eqv(in(1)->in(2),in(2)) )
51 return in(1)->in(1);
52 if (phase->eqv(in(1)->in(1),in(2)))
53 return in(1)->in(2);
54
55 // Also catch: "(X + Opaque2(Y)) - Y". In this case, 'Y' is a loop-varying
56 // trip counter and X is likely to be loop-invariant (that's how O2 Nodes
57 // are originally used, although the optimizer sometimes jiggers things).
58 // This folding through an O2 removes a loop-exit use of a loop-varying
59 // value and generally lowers register pressure in and around the loop.
60 if( in(1)->in(2)->Opcode() == Op_Opaque2 &&
61 phase->eqv(in(1)->in(2)->in(1),in(2)) )
62 return in(1)->in(1);
63 }
64
65 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this;
66 }
67
68 //------------------------------Value------------------------------------------
69 // A subtract node differences it's two inputs.
70 const Type *SubNode::Value( PhaseTransform *phase ) const {
71 const Node* in1 = in(1);
72 const Node* in2 = in(2);
73 // Either input is TOP ==> the result is TOP
74 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
75 if( t1 == Type::TOP ) return Type::TOP;
76 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
77 if( t2 == Type::TOP ) return Type::TOP;
78
79 // Not correct for SubFnode and AddFNode (must check for infinity)
80 // Equal? Subtract is zero
81 if (phase->eqv_uncast(in1, in2)) return add_id();
82
83 // Either input is BOTTOM ==> the result is the local BOTTOM
84 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM )
85 return bottom_type();
86
87 return sub(t1,t2); // Local flavor of type subtraction
88
89 }
90
91 //=============================================================================
92
93 //------------------------------Helper function--------------------------------
94 static bool ok_to_convert(Node* inc, Node* iv) {
95 // Do not collapse (x+c0)-y if "+" is a loop increment, because the
96 // "-" is loop invariant and collapsing extends the live-range of "x"
97 // to overlap with the "+", forcing another register to be used in
98 // the loop.
99 // This test will be clearer with '&&' (apply DeMorgan's rule)
100 // but I like the early cutouts that happen here.
101 const PhiNode *phi;
102 if( ( !inc->in(1)->is_Phi() ||
103 !(phi=inc->in(1)->as_Phi()) ||
104 phi->is_copy() ||
105 !phi->region()->is_CountedLoop() ||
106 inc != phi->region()->as_CountedLoop()->incr() )
107 &&
108 // Do not collapse (x+c0)-iv if "iv" is a loop induction variable,
109 // because "x" maybe invariant.
110 ( !iv->is_loop_iv() )
111 ) {
112 return true;
113 } else {
114 return false;
115 }
116 }
117 //------------------------------Ideal------------------------------------------
118 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){
119 Node *in1 = in(1);
120 Node *in2 = in(2);
121 uint op1 = in1->Opcode();
122 uint op2 = in2->Opcode();
123
124 #ifdef ASSERT
125 // Check for dead loop
126 if( phase->eqv( in1, this ) || phase->eqv( in2, this ) ||
127 ( op1 == Op_AddI || op1 == Op_SubI ) &&
128 ( phase->eqv( in1->in(1), this ) || phase->eqv( in1->in(2), this ) ||
129 phase->eqv( in1->in(1), in1 ) || phase->eqv( in1->in(2), in1 ) ) )
130 assert(false, "dead loop in SubINode::Ideal");
131 #endif
132
133 const Type *t2 = phase->type( in2 );
134 if( t2 == Type::TOP ) return NULL;
135 // Convert "x-c0" into "x+ -c0".
136 if( t2->base() == Type::Int ){ // Might be bottom or top...
137 const TypeInt *i = t2->is_int();
138 if( i->is_con() )
139 return new (phase->C, 3) AddINode(in1, phase->intcon(-i->get_con()));
140 }
141
142 // Convert "(x+c0) - y" into (x-y) + c0"
143 // Do not collapse (x+c0)-y if "+" is a loop increment or
144 // if "y" is a loop induction variable.
145 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) {
146 const Type *tadd = phase->type( in1->in(2) );
147 if( tadd->singleton() && tadd != Type::TOP ) {
148 Node *sub2 = phase->transform( new (phase->C, 3) SubINode( in1->in(1), in2 ));
149 return new (phase->C, 3) AddINode( sub2, in1->in(2) );
150 }
151 }
152
153
154 // Convert "x - (y+c0)" into "(x-y) - c0"
155 // Need the same check as in above optimization but reversed.
156 if (op2 == Op_AddI && ok_to_convert(in2, in1)) {
157 Node* in21 = in2->in(1);
158 Node* in22 = in2->in(2);
159 const TypeInt* tcon = phase->type(in22)->isa_int();
160 if (tcon != NULL && tcon->is_con()) {
161 Node* sub2 = phase->transform( new (phase->C, 3) SubINode(in1, in21) );
162 Node* neg_c0 = phase->intcon(- tcon->get_con());
163 return new (phase->C, 3) AddINode(sub2, neg_c0);
164 }
165 }
166
167 const Type *t1 = phase->type( in1 );
168 if( t1 == Type::TOP ) return NULL;
169
170 #ifdef ASSERT
171 // Check for dead loop
172 if( ( op2 == Op_AddI || op2 == Op_SubI ) &&
173 ( phase->eqv( in2->in(1), this ) || phase->eqv( in2->in(2), this ) ||
174 phase->eqv( in2->in(1), in2 ) || phase->eqv( in2->in(2), in2 ) ) )
175 assert(false, "dead loop in SubINode::Ideal");
176 #endif
177
178 // Convert "x - (x+y)" into "-y"
179 if( op2 == Op_AddI &&
180 phase->eqv( in1, in2->in(1) ) )
181 return new (phase->C, 3) SubINode( phase->intcon(0),in2->in(2));
182 // Convert "(x-y) - x" into "-y"
183 if( op1 == Op_SubI &&
184 phase->eqv( in1->in(1), in2 ) )
185 return new (phase->C, 3) SubINode( phase->intcon(0),in1->in(2));
186 // Convert "x - (y+x)" into "-y"
187 if( op2 == Op_AddI &&
188 phase->eqv( in1, in2->in(2) ) )
189 return new (phase->C, 3) SubINode( phase->intcon(0),in2->in(1));
190
191 // Convert "0 - (x-y)" into "y-x"
192 if( t1 == TypeInt::ZERO && op2 == Op_SubI )
193 return new (phase->C, 3) SubINode( in2->in(2), in2->in(1) );
194
195 // Convert "0 - (x+con)" into "-con-x"
196 jint con;
197 if( t1 == TypeInt::ZERO && op2 == Op_AddI &&
198 (con = in2->in(2)->find_int_con(0)) != 0 )
199 return new (phase->C, 3) SubINode( phase->intcon(-con), in2->in(1) );
200
201 // Convert "(X+A) - (X+B)" into "A - B"
202 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) )
203 return new (phase->C, 3) SubINode( in1->in(2), in2->in(2) );
204
205 // Convert "(A+X) - (B+X)" into "A - B"
206 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) )
207 return new (phase->C, 3) SubINode( in1->in(1), in2->in(1) );
208
209 // Convert "(A+X) - (X+B)" into "A - B"
210 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) )
211 return new (phase->C, 3) SubINode( in1->in(1), in2->in(2) );
212
213 // Convert "(X+A) - (B+X)" into "A - B"
214 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) )
215 return new (phase->C, 3) SubINode( in1->in(2), in2->in(1) );
216
217 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally
218 // nicer to optimize than subtract.
219 if( op2 == Op_SubI && in2->outcnt() == 1) {
220 Node *add1 = phase->transform( new (phase->C, 3) AddINode( in1, in2->in(2) ) );
221 return new (phase->C, 3) SubINode( add1, in2->in(1) );
222 }
223
224 return NULL;
225 }
226
227 //------------------------------sub--------------------------------------------
228 // A subtract node differences it's two inputs.
229 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const {
230 const TypeInt *r0 = t1->is_int(); // Handy access
231 const TypeInt *r1 = t2->is_int();
232 int32 lo = r0->_lo - r1->_hi;
233 int32 hi = r0->_hi - r1->_lo;
234
235 // We next check for 32-bit overflow.
236 // If that happens, we just assume all integers are possible.
237 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
238 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
239 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
240 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
241 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen));
242 else // Overflow; assume all integers
243 return TypeInt::INT;
244 }
245
246 //=============================================================================
247 //------------------------------Ideal------------------------------------------
248 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
249 Node *in1 = in(1);
250 Node *in2 = in(2);
251 uint op1 = in1->Opcode();
252 uint op2 = in2->Opcode();
253
254 #ifdef ASSERT
255 // Check for dead loop
256 if( phase->eqv( in1, this ) || phase->eqv( in2, this ) ||
257 ( op1 == Op_AddL || op1 == Op_SubL ) &&
258 ( phase->eqv( in1->in(1), this ) || phase->eqv( in1->in(2), this ) ||
259 phase->eqv( in1->in(1), in1 ) || phase->eqv( in1->in(2), in1 ) ) )
260 assert(false, "dead loop in SubLNode::Ideal");
261 #endif
262
263 if( phase->type( in2 ) == Type::TOP ) return NULL;
264 const TypeLong *i = phase->type( in2 )->isa_long();
265 // Convert "x-c0" into "x+ -c0".
266 if( i && // Might be bottom or top...
267 i->is_con() )
268 return new (phase->C, 3) AddLNode(in1, phase->longcon(-i->get_con()));
269
270 // Convert "(x+c0) - y" into (x-y) + c0"
271 // Do not collapse (x+c0)-y if "+" is a loop increment or
272 // if "y" is a loop induction variable.
273 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) {
274 Node *in11 = in1->in(1);
275 const Type *tadd = phase->type( in1->in(2) );
276 if( tadd->singleton() && tadd != Type::TOP ) {
277 Node *sub2 = phase->transform( new (phase->C, 3) SubLNode( in11, in2 ));
278 return new (phase->C, 3) AddLNode( sub2, in1->in(2) );
279 }
280 }
281
282 // Convert "x - (y+c0)" into "(x-y) - c0"
283 // Need the same check as in above optimization but reversed.
284 if (op2 == Op_AddL && ok_to_convert(in2, in1)) {
285 Node* in21 = in2->in(1);
286 Node* in22 = in2->in(2);
287 const TypeLong* tcon = phase->type(in22)->isa_long();
288 if (tcon != NULL && tcon->is_con()) {
289 Node* sub2 = phase->transform( new (phase->C, 3) SubLNode(in1, in21) );
290 Node* neg_c0 = phase->longcon(- tcon->get_con());
291 return new (phase->C, 3) AddLNode(sub2, neg_c0);
292 }
293 }
294
295 const Type *t1 = phase->type( in1 );
296 if( t1 == Type::TOP ) return NULL;
297
298 #ifdef ASSERT
299 // Check for dead loop
300 if( ( op2 == Op_AddL || op2 == Op_SubL ) &&
301 ( phase->eqv( in2->in(1), this ) || phase->eqv( in2->in(2), this ) ||
302 phase->eqv( in2->in(1), in2 ) || phase->eqv( in2->in(2), in2 ) ) )
303 assert(false, "dead loop in SubLNode::Ideal");
304 #endif
305
306 // Convert "x - (x+y)" into "-y"
307 if( op2 == Op_AddL &&
308 phase->eqv( in1, in2->in(1) ) )
309 return new (phase->C, 3) SubLNode( phase->makecon(TypeLong::ZERO), in2->in(2));
310 // Convert "x - (y+x)" into "-y"
311 if( op2 == Op_AddL &&
312 phase->eqv( in1, in2->in(2) ) )
313 return new (phase->C, 3) SubLNode( phase->makecon(TypeLong::ZERO),in2->in(1));
314
315 // Convert "0 - (x-y)" into "y-x"
316 if( phase->type( in1 ) == TypeLong::ZERO && op2 == Op_SubL )
317 return new (phase->C, 3) SubLNode( in2->in(2), in2->in(1) );
318
319 // Convert "(X+A) - (X+B)" into "A - B"
320 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) )
321 return new (phase->C, 3) SubLNode( in1->in(2), in2->in(2) );
322
323 // Convert "(A+X) - (B+X)" into "A - B"
324 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) )
325 return new (phase->C, 3) SubLNode( in1->in(1), in2->in(1) );
326
327 // Convert "A-(B-C)" into (A+C)-B"
328 if( op2 == Op_SubL && in2->outcnt() == 1) {
329 Node *add1 = phase->transform( new (phase->C, 3) AddLNode( in1, in2->in(2) ) );
330 return new (phase->C, 3) SubLNode( add1, in2->in(1) );
331 }
332
333 return NULL;
334 }
335
336 //------------------------------sub--------------------------------------------
337 // A subtract node differences it's two inputs.
338 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const {
339 const TypeLong *r0 = t1->is_long(); // Handy access
340 const TypeLong *r1 = t2->is_long();
341 jlong lo = r0->_lo - r1->_hi;
342 jlong hi = r0->_hi - r1->_lo;
343
344 // We next check for 32-bit overflow.
345 // If that happens, we just assume all integers are possible.
346 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR
347 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND
348 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR
349 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs
350 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen));
351 else // Overflow; assume all integers
352 return TypeLong::LONG;
353 }
354
355 //=============================================================================
356 //------------------------------Value------------------------------------------
357 // A subtract node differences its two inputs.
358 const Type *SubFPNode::Value( PhaseTransform *phase ) const {
359 const Node* in1 = in(1);
360 const Node* in2 = in(2);
361 // Either input is TOP ==> the result is TOP
362 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
363 if( t1 == Type::TOP ) return Type::TOP;
364 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
365 if( t2 == Type::TOP ) return Type::TOP;
366
367 // if both operands are infinity of same sign, the result is NaN; do
368 // not replace with zero
369 if( (t1->is_finite() && t2->is_finite()) ) {
370 if( phase->eqv(in1, in2) ) return add_id();
371 }
372
373 // Either input is BOTTOM ==> the result is the local BOTTOM
374 const Type *bot = bottom_type();
375 if( (t1 == bot) || (t2 == bot) ||
376 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
377 return bot;
378
379 return sub(t1,t2); // Local flavor of type subtraction
380 }
381
382
383 //=============================================================================
384 //------------------------------Ideal------------------------------------------
385 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
386 const Type *t2 = phase->type( in(2) );
387 // Convert "x-c0" into "x+ -c0".
388 if( t2->base() == Type::FloatCon ) { // Might be bottom or top...
389 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) );
390 }
391
392 // Not associative because of boundary conditions (infinity)
393 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
394 // Convert "x - (x+y)" into "-y"
395 if( in(2)->is_Add() &&
396 phase->eqv(in(1),in(2)->in(1) ) )
397 return new (phase->C, 3) SubFNode( phase->makecon(TypeF::ZERO),in(2)->in(2));
398 }
399
400 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes
401 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0.
402 //if( phase->type(in(1)) == TypeF::ZERO )
403 //return new (phase->C, 2) NegFNode(in(2));
404
405 return NULL;
406 }
407
408 //------------------------------sub--------------------------------------------
409 // A subtract node differences its two inputs.
410 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const {
411 // no folding if one of operands is infinity or NaN, do not do constant folding
412 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) {
413 return TypeF::make( t1->getf() - t2->getf() );
414 }
415 else if( g_isnan(t1->getf()) ) {
416 return t1;
417 }
418 else if( g_isnan(t2->getf()) ) {
419 return t2;
420 }
421 else {
422 return Type::FLOAT;
423 }
424 }
425
426 //=============================================================================
427 //------------------------------Ideal------------------------------------------
428 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){
429 const Type *t2 = phase->type( in(2) );
430 // Convert "x-c0" into "x+ -c0".
431 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top...
432 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) );
433 }
434
435 // Not associative because of boundary conditions (infinity)
436 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
437 // Convert "x - (x+y)" into "-y"
438 if( in(2)->is_Add() &&
439 phase->eqv(in(1),in(2)->in(1) ) )
440 return new (phase->C, 3) SubDNode( phase->makecon(TypeD::ZERO),in(2)->in(2));
441 }
442
443 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes
444 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0.
445 //if( phase->type(in(1)) == TypeD::ZERO )
446 //return new (phase->C, 2) NegDNode(in(2));
447
448 return NULL;
449 }
450
451 //------------------------------sub--------------------------------------------
452 // A subtract node differences its two inputs.
453 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const {
454 // no folding if one of operands is infinity or NaN, do not do constant folding
455 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) {
456 return TypeD::make( t1->getd() - t2->getd() );
457 }
458 else if( g_isnan(t1->getd()) ) {
459 return t1;
460 }
461 else if( g_isnan(t2->getd()) ) {
462 return t2;
463 }
464 else {
465 return Type::DOUBLE;
466 }
467 }
468
469 //=============================================================================
470 //------------------------------Idealize---------------------------------------
471 // Unlike SubNodes, compare must still flatten return value to the
472 // range -1, 0, 1.
473 // And optimizations like those for (X + Y) - X fail if overflow happens.
474 Node *CmpNode::Identity( PhaseTransform *phase ) {
475 return this;
476 }
477
478 //=============================================================================
479 //------------------------------cmp--------------------------------------------
480 // Simplify a CmpI (compare 2 integers) node, based on local information.
481 // If both inputs are constants, compare them.
482 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const {
483 const TypeInt *r0 = t1->is_int(); // Handy access
484 const TypeInt *r1 = t2->is_int();
485
486 if( r0->_hi < r1->_lo ) // Range is always low?
487 return TypeInt::CC_LT;
488 else if( r0->_lo > r1->_hi ) // Range is always high?
489 return TypeInt::CC_GT;
490
491 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
492 assert(r0->get_con() == r1->get_con(), "must be equal");
493 return TypeInt::CC_EQ; // Equal results.
494 } else if( r0->_hi == r1->_lo ) // Range is never high?
495 return TypeInt::CC_LE;
496 else if( r0->_lo == r1->_hi ) // Range is never low?
497 return TypeInt::CC_GE;
498 return TypeInt::CC; // else use worst case results
499 }
500
501 // Simplify a CmpU (compare 2 integers) node, based on local information.
502 // If both inputs are constants, compare them.
503 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const {
504 assert(!t1->isa_ptr(), "obsolete usage of CmpU");
505
506 // comparing two unsigned ints
507 const TypeInt *r0 = t1->is_int(); // Handy access
508 const TypeInt *r1 = t2->is_int();
509
510 // Current installed version
511 // Compare ranges for non-overlap
512 juint lo0 = r0->_lo;
513 juint hi0 = r0->_hi;
514 juint lo1 = r1->_lo;
515 juint hi1 = r1->_hi;
516
517 // If either one has both negative and positive values,
518 // it therefore contains both 0 and -1, and since [0..-1] is the
519 // full unsigned range, the type must act as an unsigned bottom.
520 bool bot0 = ((jint)(lo0 ^ hi0) < 0);
521 bool bot1 = ((jint)(lo1 ^ hi1) < 0);
522
523 if (bot0 || bot1) {
524 // All unsigned values are LE -1 and GE 0.
525 if (lo0 == 0 && hi0 == 0) {
526 return TypeInt::CC_LE; // 0 <= bot
527 } else if (lo1 == 0 && hi1 == 0) {
528 return TypeInt::CC_GE; // bot >= 0
529 }
530 } else {
531 // We can use ranges of the form [lo..hi] if signs are the same.
532 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
533 // results are reversed, '-' > '+' for unsigned compare
534 if (hi0 < lo1) {
535 return TypeInt::CC_LT; // smaller
536 } else if (lo0 > hi1) {
537 return TypeInt::CC_GT; // greater
538 } else if (hi0 == lo1 && lo0 == hi1) {
539 return TypeInt::CC_EQ; // Equal results
540 } else if (lo0 >= hi1) {
541 return TypeInt::CC_GE;
542 } else if (hi0 <= lo1) {
543 // Check for special case in Hashtable::get. (See below.)
544 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 &&
545 in(1)->Opcode() == Op_ModI &&
546 in(1)->in(2) == in(2) )
547 return TypeInt::CC_LT;
548 return TypeInt::CC_LE;
549 }
550 }
551 // Check for special case in Hashtable::get - the hash index is
552 // mod'ed to the table size so the following range check is useless.
553 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have
554 // to be positive.
555 // (This is a gross hack, since the sub method never
556 // looks at the structure of the node in any other case.)
557 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 &&
558 in(1)->Opcode() == Op_ModI &&
559 in(1)->in(2)->uncast() == in(2)->uncast())
560 return TypeInt::CC_LT;
561 return TypeInt::CC; // else use worst case results
562 }
563
564 //------------------------------Idealize---------------------------------------
565 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
566 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) {
567 switch (in(1)->Opcode()) {
568 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL
569 return new (phase->C, 3) CmpLNode(in(1)->in(1),in(1)->in(2));
570 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF
571 return new (phase->C, 3) CmpFNode(in(1)->in(1),in(1)->in(2));
572 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD
573 return new (phase->C, 3) CmpDNode(in(1)->in(1),in(1)->in(2));
574 //case Op_SubI:
575 // If (x - y) cannot overflow, then ((x - y) <?> 0)
576 // can be turned into (x <?> y).
577 // This is handled (with more general cases) by Ideal_sub_algebra.
578 }
579 }
580 return NULL; // No change
581 }
582
583
584 //=============================================================================
585 // Simplify a CmpL (compare 2 longs ) node, based on local information.
586 // If both inputs are constants, compare them.
587 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const {
588 const TypeLong *r0 = t1->is_long(); // Handy access
589 const TypeLong *r1 = t2->is_long();
590
591 if( r0->_hi < r1->_lo ) // Range is always low?
592 return TypeInt::CC_LT;
593 else if( r0->_lo > r1->_hi ) // Range is always high?
594 return TypeInt::CC_GT;
595
596 else if( r0->is_con() && r1->is_con() ) { // comparing constants?
597 assert(r0->get_con() == r1->get_con(), "must be equal");
598 return TypeInt::CC_EQ; // Equal results.
599 } else if( r0->_hi == r1->_lo ) // Range is never high?
600 return TypeInt::CC_LE;
601 else if( r0->_lo == r1->_hi ) // Range is never low?
602 return TypeInt::CC_GE;
603 return TypeInt::CC; // else use worst case results
604 }
605
606 //=============================================================================
607 //------------------------------sub--------------------------------------------
608 // Simplify an CmpP (compare 2 pointers) node, based on local information.
609 // If both inputs are constants, compare them.
610 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const {
611 const TypePtr *r0 = t1->is_ptr(); // Handy access
612 const TypePtr *r1 = t2->is_ptr();
613
614 // Undefined inputs makes for an undefined result
615 if( TypePtr::above_centerline(r0->_ptr) ||
616 TypePtr::above_centerline(r1->_ptr) )
617 return Type::TOP;
618
619 if (r0 == r1 && r0->singleton()) {
620 // Equal pointer constants (klasses, nulls, etc.)
621 return TypeInt::CC_EQ;
622 }
623
624 // See if it is 2 unrelated classes.
625 const TypeOopPtr* p0 = r0->isa_oopptr();
626 const TypeOopPtr* p1 = r1->isa_oopptr();
627 if (p0 && p1) {
628 Node* in1 = in(1)->uncast();
629 Node* in2 = in(2)->uncast();
630 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1, NULL);
631 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2, NULL);
632 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, NULL)) {
633 return TypeInt::CC_GT; // different pointers
634 }
635 ciKlass* klass0 = p0->klass();
636 bool xklass0 = p0->klass_is_exact();
637 ciKlass* klass1 = p1->klass();
638 bool xklass1 = p1->klass_is_exact();
639 int kps = (p0->isa_klassptr()?1:0) + (p1->isa_klassptr()?1:0);
640 if (klass0 && klass1 &&
641 kps != 1 && // both or neither are klass pointers
642 !klass0->is_interface() && // do not trust interfaces
643 !klass1->is_interface()) {
644 bool unrelated_classes = false;
645 // See if neither subclasses the other, or if the class on top
646 // is precise. In either of these cases, the compare is known
647 // to fail if at least one of the pointers is provably not null.
648 if (klass0->equals(klass1) || // if types are unequal but klasses are
649 !klass0->is_java_klass() || // types not part of Java language?
650 !klass1->is_java_klass()) { // types not part of Java language?
651 // Do nothing; we know nothing for imprecise types
652 } else if (klass0->is_subtype_of(klass1)) {
653 // If klass1's type is PRECISE, then classes are unrelated.
654 unrelated_classes = xklass1;
655 } else if (klass1->is_subtype_of(klass0)) {
656 // If klass0's type is PRECISE, then classes are unrelated.
657 unrelated_classes = xklass0;
658 } else { // Neither subtypes the other
659 unrelated_classes = true;
660 }
661 if (unrelated_classes) {
662 // The oops classes are known to be unrelated. If the joined PTRs of
663 // two oops is not Null and not Bottom, then we are sure that one
664 // of the two oops is non-null, and the comparison will always fail.
665 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
666 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
667 return TypeInt::CC_GT;
668 }
669 }
670 }
671 }
672
673 // Known constants can be compared exactly
674 // Null can be distinguished from any NotNull pointers
675 // Unknown inputs makes an unknown result
676 if( r0->singleton() ) {
677 intptr_t bits0 = r0->get_con();
678 if( r1->singleton() )
679 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
680 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
681 } else if( r1->singleton() ) {
682 intptr_t bits1 = r1->get_con();
683 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
684 } else
685 return TypeInt::CC;
686 }
687
688 //------------------------------Ideal------------------------------------------
689 // Check for the case of comparing an unknown klass loaded from the primary
690 // super-type array vs a known klass with no subtypes. This amounts to
691 // checking to see an unknown klass subtypes a known klass with no subtypes;
692 // this only happens on an exact match. We can shorten this test by 1 load.
693 Node *CmpPNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
694 // Constant pointer on right?
695 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
696 if (t2 == NULL || !t2->klass_is_exact())
697 return NULL;
698 // Get the constant klass we are comparing to.
699 ciKlass* superklass = t2->klass();
700
701 // Now check for LoadKlass on left.
702 Node* ldk1 = in(1);
703 if (ldk1->is_DecodeN()) {
704 ldk1 = ldk1->in(1);
705 if (ldk1->Opcode() != Op_LoadNKlass )
706 return NULL;
707 } else if (ldk1->Opcode() != Op_LoadKlass )
708 return NULL;
709 // Take apart the address of the LoadKlass:
710 Node* adr1 = ldk1->in(MemNode::Address);
711 intptr_t con2 = 0;
712 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
713 if (ldk2 == NULL)
714 return NULL;
715 if (con2 == oopDesc::klass_offset_in_bytes()) {
716 // We are inspecting an object's concrete class.
717 // Short-circuit the check if the query is abstract.
718 if (superklass->is_interface() ||
719 superklass->is_abstract()) {
720 // Make it come out always false:
721 this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
722 return this;
723 }
724 }
725
726 // Check for a LoadKlass from primary supertype array.
727 // Any nested loadklass from loadklass+con must be from the p.s. array.
728 if (ldk2->is_DecodeN()) {
729 // Keep ldk2 as DecodeN since it could be used in CmpP below.
730 if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
731 return NULL;
732 } else if (ldk2->Opcode() != Op_LoadKlass)
733 return NULL;
734
735 // Verify that we understand the situation
736 if (con2 != (intptr_t) superklass->super_check_offset())
737 return NULL; // Might be element-klass loading from array klass
738
739 // If 'superklass' has no subklasses and is not an interface, then we are
740 // assured that the only input which will pass the type check is
741 // 'superklass' itself.
742 //
743 // We could be more liberal here, and allow the optimization on interfaces
744 // which have a single implementor. This would require us to increase the
745 // expressiveness of the add_dependency() mechanism.
746 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now.
747
748 // Object arrays must have their base element have no subtypes
749 while (superklass->is_obj_array_klass()) {
750 ciType* elem = superklass->as_obj_array_klass()->element_type();
751 superklass = elem->as_klass();
752 }
753 if (superklass->is_instance_klass()) {
754 ciInstanceKlass* ik = superklass->as_instance_klass();
755 if (ik->has_subklass() || ik->is_interface()) return NULL;
756 // Add a dependency if there is a chance that a subclass will be added later.
757 if (!ik->is_final()) {
758 phase->C->dependencies()->assert_leaf_type(ik);
759 }
760 }
761
762 // Bypass the dependent load, and compare directly
763 this->set_req(1,ldk2);
764
765 return this;
766 }
767
768 //=============================================================================
769 //------------------------------sub--------------------------------------------
770 // Simplify an CmpN (compare 2 pointers) node, based on local information.
771 // If both inputs are constants, compare them.
772 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
773 const TypePtr *r0 = t1->make_ptr(); // Handy access
774 const TypePtr *r1 = t2->make_ptr();
775
776 // Undefined inputs makes for an undefined result
777 if( TypePtr::above_centerline(r0->_ptr) ||
778 TypePtr::above_centerline(r1->_ptr) )
779 return Type::TOP;
780
781 if (r0 == r1 && r0->singleton()) {
782 // Equal pointer constants (klasses, nulls, etc.)
783 return TypeInt::CC_EQ;
784 }
785
786 // See if it is 2 unrelated classes.
787 const TypeOopPtr* p0 = r0->isa_oopptr();
788 const TypeOopPtr* p1 = r1->isa_oopptr();
789 if (p0 && p1) {
790 ciKlass* klass0 = p0->klass();
791 bool xklass0 = p0->klass_is_exact();
792 ciKlass* klass1 = p1->klass();
793 bool xklass1 = p1->klass_is_exact();
794 int kps = (p0->isa_klassptr()?1:0) + (p1->isa_klassptr()?1:0);
795 if (klass0 && klass1 &&
796 kps != 1 && // both or neither are klass pointers
797 !klass0->is_interface() && // do not trust interfaces
798 !klass1->is_interface()) {
799 bool unrelated_classes = false;
800 // See if neither subclasses the other, or if the class on top
801 // is precise. In either of these cases, the compare is known
802 // to fail if at least one of the pointers is provably not null.
803 if (klass0->equals(klass1) || // if types are unequal but klasses are
804 !klass0->is_java_klass() || // types not part of Java language?
805 !klass1->is_java_klass()) { // types not part of Java language?
806 // Do nothing; we know nothing for imprecise types
807 } else if (klass0->is_subtype_of(klass1)) {
808 // If klass1's type is PRECISE, then classes are unrelated.
809 unrelated_classes = xklass1;
810 } else if (klass1->is_subtype_of(klass0)) {
811 // If klass0's type is PRECISE, then classes are unrelated.
812 unrelated_classes = xklass0;
813 } else { // Neither subtypes the other
814 unrelated_classes = true;
815 }
816 if (unrelated_classes) {
817 // The oops classes are known to be unrelated. If the joined PTRs of
818 // two oops is not Null and not Bottom, then we are sure that one
819 // of the two oops is non-null, and the comparison will always fail.
820 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
821 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
822 return TypeInt::CC_GT;
823 }
824 }
825 }
826 }
827
828 // Known constants can be compared exactly
829 // Null can be distinguished from any NotNull pointers
830 // Unknown inputs makes an unknown result
831 if( r0->singleton() ) {
832 intptr_t bits0 = r0->get_con();
833 if( r1->singleton() )
834 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
835 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
836 } else if( r1->singleton() ) {
837 intptr_t bits1 = r1->get_con();
838 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
839 } else
840 return TypeInt::CC;
841 }
842
843 //------------------------------Ideal------------------------------------------
844 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
845 return NULL;
846 }
847
848 //=============================================================================
849 //------------------------------Value------------------------------------------
850 // Simplify an CmpF (compare 2 floats ) node, based on local information.
851 // If both inputs are constants, compare them.
852 const Type *CmpFNode::Value( PhaseTransform *phase ) const {
853 const Node* in1 = in(1);
854 const Node* in2 = in(2);
855 // Either input is TOP ==> the result is TOP
856 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
857 if( t1 == Type::TOP ) return Type::TOP;
858 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
859 if( t2 == Type::TOP ) return Type::TOP;
860
861 // Not constants? Don't know squat - even if they are the same
862 // value! If they are NaN's they compare to LT instead of EQ.
863 const TypeF *tf1 = t1->isa_float_constant();
864 const TypeF *tf2 = t2->isa_float_constant();
865 if( !tf1 || !tf2 ) return TypeInt::CC;
866
867 // This implements the Java bytecode fcmpl, so unordered returns -1.
868 if( tf1->is_nan() || tf2->is_nan() )
869 return TypeInt::CC_LT;
870
871 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
872 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
873 assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
874 return TypeInt::CC_EQ;
875 }
876
877
878 //=============================================================================
879 //------------------------------Value------------------------------------------
880 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
881 // If both inputs are constants, compare them.
882 const Type *CmpDNode::Value( PhaseTransform *phase ) const {
883 const Node* in1 = in(1);
884 const Node* in2 = in(2);
885 // Either input is TOP ==> the result is TOP
886 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
887 if( t1 == Type::TOP ) return Type::TOP;
888 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
889 if( t2 == Type::TOP ) return Type::TOP;
890
891 // Not constants? Don't know squat - even if they are the same
892 // value! If they are NaN's they compare to LT instead of EQ.
893 const TypeD *td1 = t1->isa_double_constant();
894 const TypeD *td2 = t2->isa_double_constant();
895 if( !td1 || !td2 ) return TypeInt::CC;
896
897 // This implements the Java bytecode dcmpl, so unordered returns -1.
898 if( td1->is_nan() || td2->is_nan() )
899 return TypeInt::CC_LT;
900
901 if( td1->_d < td2->_d ) return TypeInt::CC_LT;
902 if( td1->_d > td2->_d ) return TypeInt::CC_GT;
903 assert( td1->_d == td2->_d, "do not understand FP behavior" );
904 return TypeInt::CC_EQ;
905 }
906
907 //------------------------------Ideal------------------------------------------
908 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
909 // Check if we can change this to a CmpF and remove a ConvD2F operation.
910 // Change (CMPD (F2D (float)) (ConD value))
911 // To (CMPF (float) (ConF value))
912 // Valid when 'value' does not lose precision as a float.
913 // Benefits: eliminates conversion, does not require 24-bit mode
914
915 // NaNs prevent commuting operands. This transform works regardless of the
916 // order of ConD and ConvF2D inputs by preserving the original order.
917 int idx_f2d = 1; // ConvF2D on left side?
918 if( in(idx_f2d)->Opcode() != Op_ConvF2D )
919 idx_f2d = 2; // No, swap to check for reversed args
920 int idx_con = 3-idx_f2d; // Check for the constant on other input
921
922 if( ConvertCmpD2CmpF &&
923 in(idx_f2d)->Opcode() == Op_ConvF2D &&
924 in(idx_con)->Opcode() == Op_ConD ) {
925 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
926 double t2_value_as_double = t2->_d;
927 float t2_value_as_float = (float)t2_value_as_double;
928 if( t2_value_as_double == (double)t2_value_as_float ) {
929 // Test value can be represented as a float
930 // Eliminate the conversion to double and create new comparison
931 Node *new_in1 = in(idx_f2d)->in(1);
932 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
933 if( idx_f2d != 1 ) { // Must flip args to match original order
934 Node *tmp = new_in1;
935 new_in1 = new_in2;
936 new_in2 = tmp;
937 }
938 CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
939 ? new (phase->C, 3) CmpF3Node( new_in1, new_in2 )
940 : new (phase->C, 3) CmpFNode ( new_in1, new_in2 ) ;
941 return new_cmp; // Changed to CmpFNode
942 }
943 // Testing value required the precision of a double
944 }
945 return NULL; // No change
946 }
947
948
949 //=============================================================================
950 //------------------------------cc2logical-------------------------------------
951 // Convert a condition code type to a logical type
952 const Type *BoolTest::cc2logical( const Type *CC ) const {
953 if( CC == Type::TOP ) return Type::TOP;
954 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
955 const TypeInt *ti = CC->is_int();
956 if( ti->is_con() ) { // Only 1 kind of condition codes set?
957 // Match low order 2 bits
958 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
959 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result
960 return TypeInt::make(tmp); // Boolean result
961 }
962
963 if( CC == TypeInt::CC_GE ) {
964 if( _test == ge ) return TypeInt::ONE;
965 if( _test == lt ) return TypeInt::ZERO;
966 }
967 if( CC == TypeInt::CC_LE ) {
968 if( _test == le ) return TypeInt::ONE;
969 if( _test == gt ) return TypeInt::ZERO;
970 }
971
972 return TypeInt::BOOL;
973 }
974
975 //------------------------------dump_spec-------------------------------------
976 // Print special per-node info
977 #ifndef PRODUCT
978 void BoolTest::dump_on(outputStream *st) const {
979 const char *msg[] = {"eq","gt","??","lt","ne","le","??","ge"};
980 st->print(msg[_test]);
981 }
982 #endif
983
984 //=============================================================================
985 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
986 uint BoolNode::size_of() const { return sizeof(BoolNode); }
987
988 //------------------------------operator==-------------------------------------
989 uint BoolNode::cmp( const Node &n ) const {
990 const BoolNode *b = (const BoolNode *)&n; // Cast up
991 return (_test._test == b->_test._test);
992 }
993
994 //------------------------------clone_cmp--------------------------------------
995 // Clone a compare/bool tree
996 static Node *clone_cmp( Node *cmp, Node *cmp1, Node *cmp2, PhaseGVN *gvn, BoolTest::mask test ) {
997 Node *ncmp = cmp->clone();
998 ncmp->set_req(1,cmp1);
999 ncmp->set_req(2,cmp2);
1000 ncmp = gvn->transform( ncmp );
1001 return new (gvn->C, 2) BoolNode( ncmp, test );
1002 }
1003
1004 //-------------------------------make_predicate--------------------------------
1005 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1006 if (test_value->is_Con()) return test_value;
1007 if (test_value->is_Bool()) return test_value;
1008 Compile* C = phase->C;
1009 if (test_value->is_CMove() &&
1010 test_value->in(CMoveNode::Condition)->is_Bool()) {
1011 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool();
1012 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1013 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1014 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1015 return bol;
1016 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1017 return phase->transform( bol->negate(phase) );
1018 }
1019 // Else fall through. The CMove gets in the way of the test.
1020 // It should be the case that make_predicate(bol->as_int_value()) == bol.
1021 }
1022 Node* cmp = new (C, 3) CmpINode(test_value, phase->intcon(0));
1023 cmp = phase->transform(cmp);
1024 Node* bol = new (C, 2) BoolNode(cmp, BoolTest::ne);
1025 return phase->transform(bol);
1026 }
1027
1028 //--------------------------------as_int_value---------------------------------
1029 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1030 // Inverse to make_predicate. The CMove probably boils down to a Conv2B.
1031 Node* cmov = CMoveNode::make(phase->C, NULL, this,
1032 phase->intcon(0), phase->intcon(1),
1033 TypeInt::BOOL);
1034 return phase->transform(cmov);
1035 }
1036
1037 //----------------------------------negate-------------------------------------
1038 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1039 Compile* C = phase->C;
1040 return new (C, 2) BoolNode(in(1), _test.negate());
1041 }
1042
1043
1044 //------------------------------Ideal------------------------------------------
1045 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1046 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1047 // This moves the constant to the right. Helps value-numbering.
1048 Node *cmp = in(1);
1049 if( !cmp->is_Sub() ) return NULL;
1050 int cop = cmp->Opcode();
1051 if( cop == Op_FastLock || cop == Op_FastUnlock ) return NULL;
1052 Node *cmp1 = cmp->in(1);
1053 Node *cmp2 = cmp->in(2);
1054 if( !cmp1 ) return NULL;
1055
1056 // Constant on left?
1057 Node *con = cmp1;
1058 uint op2 = cmp2->Opcode();
1059 // Move constants to the right of compare's to canonicalize.
1060 // Do not muck with Opaque1 nodes, as this indicates a loop
1061 // guard that cannot change shape.
1062 if( con->is_Con() && !cmp2->is_Con() && op2 != Op_Opaque1 &&
1063 // Because of NaN's, CmpD and CmpF are not commutative
1064 cop != Op_CmpD && cop != Op_CmpF &&
1065 // Protect against swapping inputs to a compare when it is used by a
1066 // counted loop exit, which requires maintaining the loop-limit as in(2)
1067 !is_counted_loop_exit_test() ) {
1068 // Ok, commute the constant to the right of the cmp node.
1069 // Clone the Node, getting a new Node of the same class
1070 cmp = cmp->clone();
1071 // Swap inputs to the clone
1072 cmp->swap_edges(1, 2);
1073 cmp = phase->transform( cmp );
1074 return new (phase->C, 2) BoolNode( cmp, _test.commute() );
1075 }
1076
1077 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1078 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the
1079 // test instead.
1080 int cmp1_op = cmp1->Opcode();
1081 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1082 if (cmp2_type == NULL) return NULL;
1083 Node* j_xor = cmp1;
1084 if( cmp2_type == TypeInt::ZERO &&
1085 cmp1_op == Op_XorI &&
1086 j_xor->in(1) != j_xor && // An xor of itself is dead
1087 phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1088 (_test._test == BoolTest::eq ||
1089 _test._test == BoolTest::ne) ) {
1090 Node *ncmp = phase->transform(new (phase->C, 3) CmpINode(j_xor->in(1),cmp2));
1091 return new (phase->C, 2) BoolNode( ncmp, _test.negate() );
1092 }
1093
1094 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1095 // This is a standard idiom for branching on a boolean value.
1096 Node *c2b = cmp1;
1097 if( cmp2_type == TypeInt::ZERO &&
1098 cmp1_op == Op_Conv2B &&
1099 (_test._test == BoolTest::eq ||
1100 _test._test == BoolTest::ne) ) {
1101 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1102 ? (Node*)new (phase->C, 3) CmpINode(c2b->in(1),cmp2)
1103 : (Node*)new (phase->C, 3) CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1104 );
1105 return new (phase->C, 2) BoolNode( ncmp, _test._test );
1106 }
1107
1108 // Comparing a SubI against a zero is equal to comparing the SubI
1109 // arguments directly. This only works for eq and ne comparisons
1110 // due to possible integer overflow.
1111 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1112 (cop == Op_CmpI) &&
1113 (cmp1->Opcode() == Op_SubI) &&
1114 ( cmp2_type == TypeInt::ZERO ) ) {
1115 Node *ncmp = phase->transform( new (phase->C, 3) CmpINode(cmp1->in(1),cmp1->in(2)));
1116 return new (phase->C, 2) BoolNode( ncmp, _test._test );
1117 }
1118
1119 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the
1120 // most general case because negating 0x80000000 does nothing. Needed for
1121 // the CmpF3/SubI/CmpI idiom.
1122 if( cop == Op_CmpI &&
1123 cmp1->Opcode() == Op_SubI &&
1124 cmp2_type == TypeInt::ZERO &&
1125 phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1126 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1127 Node *ncmp = phase->transform( new (phase->C, 3) CmpINode(cmp1->in(2),cmp2));
1128 return new (phase->C, 2) BoolNode( ncmp, _test.commute() );
1129 }
1130
1131 // The transformation below is not valid for either signed or unsigned
1132 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1133 // This transformation can be resurrected when we are able to
1134 // make inferences about the range of values being subtracted from
1135 // (or added to) relative to the wraparound point.
1136 //
1137 // // Remove +/-1's if possible.
1138 // // "X <= Y-1" becomes "X < Y"
1139 // // "X+1 <= Y" becomes "X < Y"
1140 // // "X < Y+1" becomes "X <= Y"
1141 // // "X-1 < Y" becomes "X <= Y"
1142 // // Do not this to compares off of the counted-loop-end. These guys are
1143 // // checking the trip counter and they want to use the post-incremented
1144 // // counter. If they use the PRE-incremented counter, then the counter has
1145 // // to be incremented in a private block on a loop backedge.
1146 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1147 // return NULL;
1148 // #ifndef PRODUCT
1149 // // Do not do this in a wash GVN pass during verification.
1150 // // Gets triggered by too many simple optimizations to be bothered with
1151 // // re-trying it again and again.
1152 // if( !phase->allow_progress() ) return NULL;
1153 // #endif
1154 // // Not valid for unsigned compare because of corner cases in involving zero.
1155 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1156 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1157 // // "0 <=u Y" is always true).
1158 // if( cmp->Opcode() == Op_CmpU ) return NULL;
1159 // int cmp2_op = cmp2->Opcode();
1160 // if( _test._test == BoolTest::le ) {
1161 // if( cmp1_op == Op_AddI &&
1162 // phase->type( cmp1->in(2) ) == TypeInt::ONE )
1163 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1164 // else if( cmp2_op == Op_AddI &&
1165 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1166 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1167 // } else if( _test._test == BoolTest::lt ) {
1168 // if( cmp1_op == Op_AddI &&
1169 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1170 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1171 // else if( cmp2_op == Op_AddI &&
1172 // phase->type( cmp2->in(2) ) == TypeInt::ONE )
1173 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1174 // }
1175
1176 return NULL;
1177 }
1178
1179 //------------------------------Value------------------------------------------
1180 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
1181 // based on local information. If the input is constant, do it.
1182 const Type *BoolNode::Value( PhaseTransform *phase ) const {
1183 return _test.cc2logical( phase->type( in(1) ) );
1184 }
1185
1186 //------------------------------dump_spec--------------------------------------
1187 // Dump special per-node info
1188 #ifndef PRODUCT
1189 void BoolNode::dump_spec(outputStream *st) const {
1190 st->print("[");
1191 _test.dump_on(st);
1192 st->print("]");
1193 }
1194 #endif
1195
1196 //------------------------------is_counted_loop_exit_test--------------------------------------
1197 // Returns true if node is used by a counted loop node.
1198 bool BoolNode::is_counted_loop_exit_test() {
1199 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
1200 Node* use = fast_out(i);
1201 if (use->is_CountedLoopEnd()) {
1202 return true;
1203 }
1204 }
1205 return false;
1206 }
1207
1208 //=============================================================================
1209 //------------------------------NegNode----------------------------------------
1210 Node *NegFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1211 if( in(1)->Opcode() == Op_SubF )
1212 return new (phase->C, 3) SubFNode( in(1)->in(2), in(1)->in(1) );
1213 return NULL;
1214 }
1215
1216 Node *NegDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1217 if( in(1)->Opcode() == Op_SubD )
1218 return new (phase->C, 3) SubDNode( in(1)->in(2), in(1)->in(1) );
1219 return NULL;
1220 }
1221
1222
1223 //=============================================================================
1224 //------------------------------Value------------------------------------------
1225 // Compute sqrt
1226 const Type *SqrtDNode::Value( PhaseTransform *phase ) const {
1227 const Type *t1 = phase->type( in(1) );
1228 if( t1 == Type::TOP ) return Type::TOP;
1229 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1230 double d = t1->getd();
1231 if( d < 0.0 ) return Type::DOUBLE;
1232 return TypeD::make( sqrt( d ) );
1233 }
1234
1235 //=============================================================================
1236 //------------------------------Value------------------------------------------
1237 // Compute cos
1238 const Type *CosDNode::Value( PhaseTransform *phase ) const {
1239 const Type *t1 = phase->type( in(1) );
1240 if( t1 == Type::TOP ) return Type::TOP;
1241 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1242 double d = t1->getd();
1243 if( d < 0.0 ) return Type::DOUBLE;
1244 return TypeD::make( SharedRuntime::dcos( d ) );
1245 }
1246
1247 //=============================================================================
1248 //------------------------------Value------------------------------------------
1249 // Compute sin
1250 const Type *SinDNode::Value( PhaseTransform *phase ) const {
1251 const Type *t1 = phase->type( in(1) );
1252 if( t1 == Type::TOP ) return Type::TOP;
1253 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1254 double d = t1->getd();
1255 if( d < 0.0 ) return Type::DOUBLE;
1256 return TypeD::make( SharedRuntime::dsin( d ) );
1257 }
1258
1259 //=============================================================================
1260 //------------------------------Value------------------------------------------
1261 // Compute tan
1262 const Type *TanDNode::Value( PhaseTransform *phase ) const {
1263 const Type *t1 = phase->type( in(1) );
1264 if( t1 == Type::TOP ) return Type::TOP;
1265 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1266 double d = t1->getd();
1267 if( d < 0.0 ) return Type::DOUBLE;
1268 return TypeD::make( SharedRuntime::dtan( d ) );
1269 }
1270
1271 //=============================================================================
1272 //------------------------------Value------------------------------------------
1273 // Compute log
1274 const Type *LogDNode::Value( PhaseTransform *phase ) const {
1275 const Type *t1 = phase->type( in(1) );
1276 if( t1 == Type::TOP ) return Type::TOP;
1277 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1278 double d = t1->getd();
1279 if( d < 0.0 ) return Type::DOUBLE;
1280 return TypeD::make( SharedRuntime::dlog( d ) );
1281 }
1282
1283 //=============================================================================
1284 //------------------------------Value------------------------------------------
1285 // Compute log10
1286 const Type *Log10DNode::Value( PhaseTransform *phase ) const {
1287 const Type *t1 = phase->type( in(1) );
1288 if( t1 == Type::TOP ) return Type::TOP;
1289 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1290 double d = t1->getd();
1291 if( d < 0.0 ) return Type::DOUBLE;
1292 return TypeD::make( SharedRuntime::dlog10( d ) );
1293 }
1294
1295 //=============================================================================
1296 //------------------------------Value------------------------------------------
1297 // Compute exp
1298 const Type *ExpDNode::Value( PhaseTransform *phase ) const {
1299 const Type *t1 = phase->type( in(1) );
1300 if( t1 == Type::TOP ) return Type::TOP;
1301 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1302 double d = t1->getd();
1303 if( d < 0.0 ) return Type::DOUBLE;
1304 return TypeD::make( SharedRuntime::dexp( d ) );
1305 }
1306
1307
1308 //=============================================================================
1309 //------------------------------Value------------------------------------------
1310 // Compute pow
1311 const Type *PowDNode::Value( PhaseTransform *phase ) const {
1312 const Type *t1 = phase->type( in(1) );
1313 if( t1 == Type::TOP ) return Type::TOP;
1314 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1315 const Type *t2 = phase->type( in(2) );
1316 if( t2 == Type::TOP ) return Type::TOP;
1317 if( t2->base() != Type::DoubleCon ) return Type::DOUBLE;
1318 double d1 = t1->getd();
1319 double d2 = t2->getd();
1320 if( d1 < 0.0 ) return Type::DOUBLE;
1321 if( d2 < 0.0 ) return Type::DOUBLE;
1322 return TypeD::make( SharedRuntime::dpow( d1, d2 ) );
1323 }