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