1 /*
2 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
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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).
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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_loaded() && !klass0->is_interface() && // do not trust interfaces
643 klass1->is_loaded() && !klass1->is_interface() &&
644 (!klass0->is_obj_array_klass() ||
645 !klass0->as_obj_array_klass()->base_element_klass()->is_interface()) &&
646 (!klass1->is_obj_array_klass() ||
647 !klass1->as_obj_array_klass()->base_element_klass()->is_interface())) {
648 bool unrelated_classes = false;
649 // See if neither subclasses the other, or if the class on top
650 // is precise. In either of these cases, the compare is known
651 // to fail if at least one of the pointers is provably not null.
652 if (klass0->equals(klass1) || // if types are unequal but klasses are
653 !klass0->is_java_klass() || // types not part of Java language?
654 !klass1->is_java_klass()) { // types not part of Java language?
655 // Do nothing; we know nothing for imprecise types
656 } else if (klass0->is_subtype_of(klass1)) {
657 // If klass1's type is PRECISE, then classes are unrelated.
658 unrelated_classes = xklass1;
659 } else if (klass1->is_subtype_of(klass0)) {
660 // If klass0's type is PRECISE, then classes are unrelated.
661 unrelated_classes = xklass0;
662 } else { // Neither subtypes the other
663 unrelated_classes = true;
664 }
665 if (unrelated_classes) {
666 // The oops classes are known to be unrelated. If the joined PTRs of
667 // two oops is not Null and not Bottom, then we are sure that one
668 // of the two oops is non-null, and the comparison will always fail.
669 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
670 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
671 return TypeInt::CC_GT;
672 }
673 }
674 }
675 }
676
677 // Known constants can be compared exactly
678 // Null can be distinguished from any NotNull pointers
679 // Unknown inputs makes an unknown result
680 if( r0->singleton() ) {
681 intptr_t bits0 = r0->get_con();
682 if( r1->singleton() )
683 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
684 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
685 } else if( r1->singleton() ) {
686 intptr_t bits1 = r1->get_con();
687 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
688 } else
689 return TypeInt::CC;
690 }
691
692 //------------------------------Ideal------------------------------------------
693 // Check for the case of comparing an unknown klass loaded from the primary
694 // super-type array vs a known klass with no subtypes. This amounts to
695 // checking to see an unknown klass subtypes a known klass with no subtypes;
696 // this only happens on an exact match. We can shorten this test by 1 load.
697 Node *CmpPNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
698 // Constant pointer on right?
699 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
700 if (t2 == NULL || !t2->klass_is_exact())
701 return NULL;
702 // Get the constant klass we are comparing to.
703 ciKlass* superklass = t2->klass();
704
705 // Now check for LoadKlass on left.
706 Node* ldk1 = in(1);
707 if (ldk1->is_DecodeN()) {
708 ldk1 = ldk1->in(1);
709 if (ldk1->Opcode() != Op_LoadNKlass )
710 return NULL;
711 } else if (ldk1->Opcode() != Op_LoadKlass )
712 return NULL;
713 // Take apart the address of the LoadKlass:
714 Node* adr1 = ldk1->in(MemNode::Address);
715 intptr_t con2 = 0;
716 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
717 if (ldk2 == NULL)
718 return NULL;
719 if (con2 == oopDesc::klass_offset_in_bytes()) {
720 // We are inspecting an object's concrete class.
721 // Short-circuit the check if the query is abstract.
722 if (superklass->is_interface() ||
723 superklass->is_abstract()) {
724 // Make it come out always false:
725 this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
726 return this;
727 }
728 }
729
730 // Check for a LoadKlass from primary supertype array.
731 // Any nested loadklass from loadklass+con must be from the p.s. array.
732 if (ldk2->is_DecodeN()) {
733 // Keep ldk2 as DecodeN since it could be used in CmpP below.
734 if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
735 return NULL;
736 } else if (ldk2->Opcode() != Op_LoadKlass)
737 return NULL;
738
739 // Verify that we understand the situation
740 if (con2 != (intptr_t) superklass->super_check_offset())
741 return NULL; // Might be element-klass loading from array klass
742
743 // If 'superklass' has no subklasses and is not an interface, then we are
744 // assured that the only input which will pass the type check is
745 // 'superklass' itself.
746 //
747 // We could be more liberal here, and allow the optimization on interfaces
748 // which have a single implementor. This would require us to increase the
749 // expressiveness of the add_dependency() mechanism.
750 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now.
751
752 // Object arrays must have their base element have no subtypes
753 while (superklass->is_obj_array_klass()) {
754 ciType* elem = superklass->as_obj_array_klass()->element_type();
755 superklass = elem->as_klass();
756 }
757 if (superklass->is_instance_klass()) {
758 ciInstanceKlass* ik = superklass->as_instance_klass();
759 if (ik->has_subklass() || ik->is_interface()) return NULL;
760 // Add a dependency if there is a chance that a subclass will be added later.
761 if (!ik->is_final()) {
762 phase->C->dependencies()->assert_leaf_type(ik);
763 }
764 }
765
766 // Bypass the dependent load, and compare directly
767 this->set_req(1,ldk2);
768
769 return this;
770 }
771
772 //=============================================================================
773 //------------------------------sub--------------------------------------------
774 // Simplify an CmpN (compare 2 pointers) node, based on local information.
775 // If both inputs are constants, compare them.
776 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
777 const TypePtr *r0 = t1->make_ptr(); // Handy access
778 const TypePtr *r1 = t2->make_ptr();
779
780 // Undefined inputs makes for an undefined result
781 if( TypePtr::above_centerline(r0->_ptr) ||
782 TypePtr::above_centerline(r1->_ptr) )
783 return Type::TOP;
784
785 if (r0 == r1 && r0->singleton()) {
786 // Equal pointer constants (klasses, nulls, etc.)
787 return TypeInt::CC_EQ;
788 }
789
790 // See if it is 2 unrelated classes.
791 const TypeOopPtr* p0 = r0->isa_oopptr();
792 const TypeOopPtr* p1 = r1->isa_oopptr();
793 if (p0 && p1) {
794 ciKlass* klass0 = p0->klass();
795 bool xklass0 = p0->klass_is_exact();
796 ciKlass* klass1 = p1->klass();
797 bool xklass1 = p1->klass_is_exact();
798 int kps = (p0->isa_klassptr()?1:0) + (p1->isa_klassptr()?1:0);
799 if (klass0 && klass1 &&
800 kps != 1 && // both or neither are klass pointers
801 !klass0->is_interface() && // do not trust interfaces
802 !klass1->is_interface()) {
803 bool unrelated_classes = false;
804 // See if neither subclasses the other, or if the class on top
805 // is precise. In either of these cases, the compare is known
806 // to fail if at least one of the pointers is provably not null.
807 if (klass0->equals(klass1) || // if types are unequal but klasses are
808 !klass0->is_java_klass() || // types not part of Java language?
809 !klass1->is_java_klass()) { // types not part of Java language?
810 // Do nothing; we know nothing for imprecise types
811 } else if (klass0->is_subtype_of(klass1)) {
812 // If klass1's type is PRECISE, then classes are unrelated.
813 unrelated_classes = xklass1;
814 } else if (klass1->is_subtype_of(klass0)) {
815 // If klass0's type is PRECISE, then classes are unrelated.
816 unrelated_classes = xklass0;
817 } else { // Neither subtypes the other
818 unrelated_classes = true;
819 }
820 if (unrelated_classes) {
821 // The oops classes are known to be unrelated. If the joined PTRs of
822 // two oops is not Null and not Bottom, then we are sure that one
823 // of the two oops is non-null, and the comparison will always fail.
824 TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
825 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
826 return TypeInt::CC_GT;
827 }
828 }
829 }
830 }
831
832 // Known constants can be compared exactly
833 // Null can be distinguished from any NotNull pointers
834 // Unknown inputs makes an unknown result
835 if( r0->singleton() ) {
836 intptr_t bits0 = r0->get_con();
837 if( r1->singleton() )
838 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
839 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
840 } else if( r1->singleton() ) {
841 intptr_t bits1 = r1->get_con();
842 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
843 } else
844 return TypeInt::CC;
845 }
846
847 //------------------------------Ideal------------------------------------------
848 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
849 return NULL;
850 }
851
852 //=============================================================================
853 //------------------------------Value------------------------------------------
854 // Simplify an CmpF (compare 2 floats ) node, based on local information.
855 // If both inputs are constants, compare them.
856 const Type *CmpFNode::Value( PhaseTransform *phase ) const {
857 const Node* in1 = in(1);
858 const Node* in2 = in(2);
859 // Either input is TOP ==> the result is TOP
860 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
861 if( t1 == Type::TOP ) return Type::TOP;
862 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
863 if( t2 == Type::TOP ) return Type::TOP;
864
865 // Not constants? Don't know squat - even if they are the same
866 // value! If they are NaN's they compare to LT instead of EQ.
867 const TypeF *tf1 = t1->isa_float_constant();
868 const TypeF *tf2 = t2->isa_float_constant();
869 if( !tf1 || !tf2 ) return TypeInt::CC;
870
871 // This implements the Java bytecode fcmpl, so unordered returns -1.
872 if( tf1->is_nan() || tf2->is_nan() )
873 return TypeInt::CC_LT;
874
875 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
876 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
877 assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
878 return TypeInt::CC_EQ;
879 }
880
881
882 //=============================================================================
883 //------------------------------Value------------------------------------------
884 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
885 // If both inputs are constants, compare them.
886 const Type *CmpDNode::Value( PhaseTransform *phase ) const {
887 const Node* in1 = in(1);
888 const Node* in2 = in(2);
889 // Either input is TOP ==> the result is TOP
890 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
891 if( t1 == Type::TOP ) return Type::TOP;
892 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
893 if( t2 == Type::TOP ) return Type::TOP;
894
895 // Not constants? Don't know squat - even if they are the same
896 // value! If they are NaN's they compare to LT instead of EQ.
897 const TypeD *td1 = t1->isa_double_constant();
898 const TypeD *td2 = t2->isa_double_constant();
899 if( !td1 || !td2 ) return TypeInt::CC;
900
901 // This implements the Java bytecode dcmpl, so unordered returns -1.
902 if( td1->is_nan() || td2->is_nan() )
903 return TypeInt::CC_LT;
904
905 if( td1->_d < td2->_d ) return TypeInt::CC_LT;
906 if( td1->_d > td2->_d ) return TypeInt::CC_GT;
907 assert( td1->_d == td2->_d, "do not understand FP behavior" );
908 return TypeInt::CC_EQ;
909 }
910
911 //------------------------------Ideal------------------------------------------
912 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
913 // Check if we can change this to a CmpF and remove a ConvD2F operation.
914 // Change (CMPD (F2D (float)) (ConD value))
915 // To (CMPF (float) (ConF value))
916 // Valid when 'value' does not lose precision as a float.
917 // Benefits: eliminates conversion, does not require 24-bit mode
918
919 // NaNs prevent commuting operands. This transform works regardless of the
920 // order of ConD and ConvF2D inputs by preserving the original order.
921 int idx_f2d = 1; // ConvF2D on left side?
922 if( in(idx_f2d)->Opcode() != Op_ConvF2D )
923 idx_f2d = 2; // No, swap to check for reversed args
924 int idx_con = 3-idx_f2d; // Check for the constant on other input
925
926 if( ConvertCmpD2CmpF &&
927 in(idx_f2d)->Opcode() == Op_ConvF2D &&
928 in(idx_con)->Opcode() == Op_ConD ) {
929 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
930 double t2_value_as_double = t2->_d;
931 float t2_value_as_float = (float)t2_value_as_double;
932 if( t2_value_as_double == (double)t2_value_as_float ) {
933 // Test value can be represented as a float
934 // Eliminate the conversion to double and create new comparison
935 Node *new_in1 = in(idx_f2d)->in(1);
936 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
937 if( idx_f2d != 1 ) { // Must flip args to match original order
938 Node *tmp = new_in1;
939 new_in1 = new_in2;
940 new_in2 = tmp;
941 }
942 CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
943 ? new (phase->C, 3) CmpF3Node( new_in1, new_in2 )
944 : new (phase->C, 3) CmpFNode ( new_in1, new_in2 ) ;
945 return new_cmp; // Changed to CmpFNode
946 }
947 // Testing value required the precision of a double
948 }
949 return NULL; // No change
950 }
951
952
953 //=============================================================================
954 //------------------------------cc2logical-------------------------------------
955 // Convert a condition code type to a logical type
956 const Type *BoolTest::cc2logical( const Type *CC ) const {
957 if( CC == Type::TOP ) return Type::TOP;
958 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
959 const TypeInt *ti = CC->is_int();
960 if( ti->is_con() ) { // Only 1 kind of condition codes set?
961 // Match low order 2 bits
962 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
963 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result
964 return TypeInt::make(tmp); // Boolean result
965 }
966
967 if( CC == TypeInt::CC_GE ) {
968 if( _test == ge ) return TypeInt::ONE;
969 if( _test == lt ) return TypeInt::ZERO;
970 }
971 if( CC == TypeInt::CC_LE ) {
972 if( _test == le ) return TypeInt::ONE;
973 if( _test == gt ) return TypeInt::ZERO;
974 }
975
976 return TypeInt::BOOL;
977 }
978
979 //------------------------------dump_spec-------------------------------------
980 // Print special per-node info
981 #ifndef PRODUCT
982 void BoolTest::dump_on(outputStream *st) const {
983 const char *msg[] = {"eq","gt","??","lt","ne","le","??","ge"};
984 st->print(msg[_test]);
985 }
986 #endif
987
988 //=============================================================================
989 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
990 uint BoolNode::size_of() const { return sizeof(BoolNode); }
991
992 //------------------------------operator==-------------------------------------
993 uint BoolNode::cmp( const Node &n ) const {
994 const BoolNode *b = (const BoolNode *)&n; // Cast up
995 return (_test._test == b->_test._test);
996 }
997
998 //------------------------------clone_cmp--------------------------------------
999 // Clone a compare/bool tree
1000 static Node *clone_cmp( Node *cmp, Node *cmp1, Node *cmp2, PhaseGVN *gvn, BoolTest::mask test ) {
1001 Node *ncmp = cmp->clone();
1002 ncmp->set_req(1,cmp1);
1003 ncmp->set_req(2,cmp2);
1004 ncmp = gvn->transform( ncmp );
1005 return new (gvn->C, 2) BoolNode( ncmp, test );
1006 }
1007
1008 //-------------------------------make_predicate--------------------------------
1009 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1010 if (test_value->is_Con()) return test_value;
1011 if (test_value->is_Bool()) return test_value;
1012 Compile* C = phase->C;
1013 if (test_value->is_CMove() &&
1014 test_value->in(CMoveNode::Condition)->is_Bool()) {
1015 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool();
1016 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1017 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1018 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1019 return bol;
1020 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1021 return phase->transform( bol->negate(phase) );
1022 }
1023 // Else fall through. The CMove gets in the way of the test.
1024 // It should be the case that make_predicate(bol->as_int_value()) == bol.
1025 }
1026 Node* cmp = new (C, 3) CmpINode(test_value, phase->intcon(0));
1027 cmp = phase->transform(cmp);
1028 Node* bol = new (C, 2) BoolNode(cmp, BoolTest::ne);
1029 return phase->transform(bol);
1030 }
1031
1032 //--------------------------------as_int_value---------------------------------
1033 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1034 // Inverse to make_predicate. The CMove probably boils down to a Conv2B.
1035 Node* cmov = CMoveNode::make(phase->C, NULL, this,
1036 phase->intcon(0), phase->intcon(1),
1037 TypeInt::BOOL);
1038 return phase->transform(cmov);
1039 }
1040
1041 //----------------------------------negate-------------------------------------
1042 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1043 Compile* C = phase->C;
1044 return new (C, 2) BoolNode(in(1), _test.negate());
1045 }
1046
1047
1048 //------------------------------Ideal------------------------------------------
1049 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1050 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1051 // This moves the constant to the right. Helps value-numbering.
1052 Node *cmp = in(1);
1053 if( !cmp->is_Sub() ) return NULL;
1054 int cop = cmp->Opcode();
1055 if( cop == Op_FastLock || cop == Op_FastUnlock ) return NULL;
1056 Node *cmp1 = cmp->in(1);
1057 Node *cmp2 = cmp->in(2);
1058 if( !cmp1 ) return NULL;
1059
1060 // Constant on left?
1061 Node *con = cmp1;
1062 uint op2 = cmp2->Opcode();
1063 // Move constants to the right of compare's to canonicalize.
1064 // Do not muck with Opaque1 nodes, as this indicates a loop
1065 // guard that cannot change shape.
1066 if( con->is_Con() && !cmp2->is_Con() && op2 != Op_Opaque1 &&
1067 // Because of NaN's, CmpD and CmpF are not commutative
1068 cop != Op_CmpD && cop != Op_CmpF &&
1069 // Protect against swapping inputs to a compare when it is used by a
1070 // counted loop exit, which requires maintaining the loop-limit as in(2)
1071 !is_counted_loop_exit_test() ) {
1072 // Ok, commute the constant to the right of the cmp node.
1073 // Clone the Node, getting a new Node of the same class
1074 cmp = cmp->clone();
1075 // Swap inputs to the clone
1076 cmp->swap_edges(1, 2);
1077 cmp = phase->transform( cmp );
1078 return new (phase->C, 2) BoolNode( cmp, _test.commute() );
1079 }
1080
1081 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1082 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the
1083 // test instead.
1084 int cmp1_op = cmp1->Opcode();
1085 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1086 if (cmp2_type == NULL) return NULL;
1087 Node* j_xor = cmp1;
1088 if( cmp2_type == TypeInt::ZERO &&
1089 cmp1_op == Op_XorI &&
1090 j_xor->in(1) != j_xor && // An xor of itself is dead
1091 phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1092 (_test._test == BoolTest::eq ||
1093 _test._test == BoolTest::ne) ) {
1094 Node *ncmp = phase->transform(new (phase->C, 3) CmpINode(j_xor->in(1),cmp2));
1095 return new (phase->C, 2) BoolNode( ncmp, _test.negate() );
1096 }
1097
1098 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1099 // This is a standard idiom for branching on a boolean value.
1100 Node *c2b = cmp1;
1101 if( cmp2_type == TypeInt::ZERO &&
1102 cmp1_op == Op_Conv2B &&
1103 (_test._test == BoolTest::eq ||
1104 _test._test == BoolTest::ne) ) {
1105 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1106 ? (Node*)new (phase->C, 3) CmpINode(c2b->in(1),cmp2)
1107 : (Node*)new (phase->C, 3) CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1108 );
1109 return new (phase->C, 2) BoolNode( ncmp, _test._test );
1110 }
1111
1112 // Comparing a SubI against a zero is equal to comparing the SubI
1113 // arguments directly. This only works for eq and ne comparisons
1114 // due to possible integer overflow.
1115 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1116 (cop == Op_CmpI) &&
1117 (cmp1->Opcode() == Op_SubI) &&
1118 ( cmp2_type == TypeInt::ZERO ) ) {
1119 Node *ncmp = phase->transform( new (phase->C, 3) CmpINode(cmp1->in(1),cmp1->in(2)));
1120 return new (phase->C, 2) BoolNode( ncmp, _test._test );
1121 }
1122
1123 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the
1124 // most general case because negating 0x80000000 does nothing. Needed for
1125 // the CmpF3/SubI/CmpI idiom.
1126 if( cop == Op_CmpI &&
1127 cmp1->Opcode() == Op_SubI &&
1128 cmp2_type == TypeInt::ZERO &&
1129 phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1130 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1131 Node *ncmp = phase->transform( new (phase->C, 3) CmpINode(cmp1->in(2),cmp2));
1132 return new (phase->C, 2) BoolNode( ncmp, _test.commute() );
1133 }
1134
1135 // The transformation below is not valid for either signed or unsigned
1136 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1137 // This transformation can be resurrected when we are able to
1138 // make inferences about the range of values being subtracted from
1139 // (or added to) relative to the wraparound point.
1140 //
1141 // // Remove +/-1's if possible.
1142 // // "X <= Y-1" becomes "X < Y"
1143 // // "X+1 <= Y" becomes "X < Y"
1144 // // "X < Y+1" becomes "X <= Y"
1145 // // "X-1 < Y" becomes "X <= Y"
1146 // // Do not this to compares off of the counted-loop-end. These guys are
1147 // // checking the trip counter and they want to use the post-incremented
1148 // // counter. If they use the PRE-incremented counter, then the counter has
1149 // // to be incremented in a private block on a loop backedge.
1150 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1151 // return NULL;
1152 // #ifndef PRODUCT
1153 // // Do not do this in a wash GVN pass during verification.
1154 // // Gets triggered by too many simple optimizations to be bothered with
1155 // // re-trying it again and again.
1156 // if( !phase->allow_progress() ) return NULL;
1157 // #endif
1158 // // Not valid for unsigned compare because of corner cases in involving zero.
1159 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1160 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1161 // // "0 <=u Y" is always true).
1162 // if( cmp->Opcode() == Op_CmpU ) return NULL;
1163 // int cmp2_op = cmp2->Opcode();
1164 // if( _test._test == BoolTest::le ) {
1165 // if( cmp1_op == Op_AddI &&
1166 // phase->type( cmp1->in(2) ) == TypeInt::ONE )
1167 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1168 // else if( cmp2_op == Op_AddI &&
1169 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1170 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1171 // } else if( _test._test == BoolTest::lt ) {
1172 // if( cmp1_op == Op_AddI &&
1173 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1174 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1175 // else if( cmp2_op == Op_AddI &&
1176 // phase->type( cmp2->in(2) ) == TypeInt::ONE )
1177 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1178 // }
1179
1180 return NULL;
1181 }
1182
1183 //------------------------------Value------------------------------------------
1184 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
1185 // based on local information. If the input is constant, do it.
1186 const Type *BoolNode::Value( PhaseTransform *phase ) const {
1187 return _test.cc2logical( phase->type( in(1) ) );
1188 }
1189
1190 //------------------------------dump_spec--------------------------------------
1191 // Dump special per-node info
1192 #ifndef PRODUCT
1193 void BoolNode::dump_spec(outputStream *st) const {
1194 st->print("[");
1195 _test.dump_on(st);
1196 st->print("]");
1197 }
1198 #endif
1199
1200 //------------------------------is_counted_loop_exit_test--------------------------------------
1201 // Returns true if node is used by a counted loop node.
1202 bool BoolNode::is_counted_loop_exit_test() {
1203 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
1204 Node* use = fast_out(i);
1205 if (use->is_CountedLoopEnd()) {
1206 return true;
1207 }
1208 }
1209 return false;
1210 }
1211
1212 //=============================================================================
1213 //------------------------------NegNode----------------------------------------
1214 Node *NegFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1215 if( in(1)->Opcode() == Op_SubF )
1216 return new (phase->C, 3) SubFNode( in(1)->in(2), in(1)->in(1) );
1217 return NULL;
1218 }
1219
1220 Node *NegDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1221 if( in(1)->Opcode() == Op_SubD )
1222 return new (phase->C, 3) SubDNode( in(1)->in(2), in(1)->in(1) );
1223 return NULL;
1224 }
1225
1226
1227 //=============================================================================
1228 //------------------------------Value------------------------------------------
1229 // Compute sqrt
1230 const Type *SqrtDNode::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( sqrt( d ) );
1237 }
1238
1239 //=============================================================================
1240 //------------------------------Value------------------------------------------
1241 // Compute cos
1242 const Type *CosDNode::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 return TypeD::make( StubRoutines::intrinsic_cos( d ) );
1248 }
1249
1250 //=============================================================================
1251 //------------------------------Value------------------------------------------
1252 // Compute sin
1253 const Type *SinDNode::Value( PhaseTransform *phase ) const {
1254 const Type *t1 = phase->type( in(1) );
1255 if( t1 == Type::TOP ) return Type::TOP;
1256 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1257 double d = t1->getd();
1258 return TypeD::make( StubRoutines::intrinsic_sin( d ) );
1259 }
1260
1261 //=============================================================================
1262 //------------------------------Value------------------------------------------
1263 // Compute tan
1264 const Type *TanDNode::Value( PhaseTransform *phase ) const {
1265 const Type *t1 = phase->type( in(1) );
1266 if( t1 == Type::TOP ) return Type::TOP;
1267 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1268 double d = t1->getd();
1269 return TypeD::make( StubRoutines::intrinsic_tan( d ) );
1270 }
1271
1272 //=============================================================================
1273 //------------------------------Value------------------------------------------
1274 // Compute log
1275 const Type *LogDNode::Value( PhaseTransform *phase ) const {
1276 const Type *t1 = phase->type( in(1) );
1277 if( t1 == Type::TOP ) return Type::TOP;
1278 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1279 double d = t1->getd();
1280 return TypeD::make( StubRoutines::intrinsic_log( 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 return TypeD::make( StubRoutines::intrinsic_log10( d ) );
1292 }
1293
1294 //=============================================================================
1295 //------------------------------Value------------------------------------------
1296 // Compute exp
1297 const Type *ExpDNode::Value( PhaseTransform *phase ) const {
1298 const Type *t1 = phase->type( in(1) );
1299 if( t1 == Type::TOP ) return Type::TOP;
1300 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1301 double d = t1->getd();
1302 return TypeD::make( StubRoutines::intrinsic_exp( d ) );
1303 }
1304
1305
1306 //=============================================================================
1307 //------------------------------Value------------------------------------------
1308 // Compute pow
1309 const Type *PowDNode::Value( PhaseTransform *phase ) const {
1310 const Type *t1 = phase->type( in(1) );
1311 if( t1 == Type::TOP ) return Type::TOP;
1312 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
1313 const Type *t2 = phase->type( in(2) );
1314 if( t2 == Type::TOP ) return Type::TOP;
1315 if( t2->base() != Type::DoubleCon ) return Type::DOUBLE;
1316 double d1 = t1->getd();
1317 double d2 = t2->getd();
1318 if( d1 < 0.0 ) return Type::DOUBLE;
1319 if( d2 < 0.0 ) return Type::DOUBLE;
1320 return TypeD::make( StubRoutines::intrinsic_pow( d1, d2 ) );
1321 }