Wed, 09 Nov 2011 06:14:32 -0800
7109887: java/util/Arrays/CopyMethods.java fails with -XX:+DeoptimizeALot
Summary: zero array when compiled code is deoptimized.
Reviewed-by: never, twisti
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.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
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23 */
25 #include "precompiled.hpp"
26 #include "memory/allocation.inline.hpp"
27 #include "opto/addnode.hpp"
28 #include "opto/compile.hpp"
29 #include "opto/connode.hpp"
30 #include "opto/machnode.hpp"
31 #include "opto/matcher.hpp"
32 #include "opto/memnode.hpp"
33 #include "opto/phaseX.hpp"
34 #include "opto/subnode.hpp"
35 #include "runtime/sharedRuntime.hpp"
37 // Optimization - Graph Style
39 //=============================================================================
40 //------------------------------hash-------------------------------------------
41 uint ConNode::hash() const {
42 return (uintptr_t)in(TypeFunc::Control) + _type->hash();
43 }
45 //------------------------------make-------------------------------------------
46 ConNode *ConNode::make( Compile* C, const Type *t ) {
47 switch( t->basic_type() ) {
48 case T_INT: return new (C, 1) ConINode( t->is_int() );
49 case T_LONG: return new (C, 1) ConLNode( t->is_long() );
50 case T_FLOAT: return new (C, 1) ConFNode( t->is_float_constant() );
51 case T_DOUBLE: return new (C, 1) ConDNode( t->is_double_constant() );
52 case T_VOID: return new (C, 1) ConNode ( Type::TOP );
53 case T_OBJECT: return new (C, 1) ConPNode( t->is_oopptr() );
54 case T_ARRAY: return new (C, 1) ConPNode( t->is_aryptr() );
55 case T_ADDRESS: return new (C, 1) ConPNode( t->is_ptr() );
56 case T_NARROWOOP: return new (C, 1) ConNNode( t->is_narrowoop() );
57 // Expected cases: TypePtr::NULL_PTR, any is_rawptr()
58 // Also seen: AnyPtr(TopPTR *+top); from command line:
59 // r -XX:+PrintOpto -XX:CIStart=285 -XX:+CompileTheWorld -XX:CompileTheWorldStartAt=660
60 // %%%% Stop using TypePtr::NULL_PTR to represent nulls: use either TypeRawPtr::NULL_PTR
61 // or else TypeOopPtr::NULL_PTR. Then set Type::_basic_type[AnyPtr] = T_ILLEGAL
62 }
63 ShouldNotReachHere();
64 return NULL;
65 }
67 //=============================================================================
68 /*
69 The major change is for CMoveP and StrComp. They have related but slightly
70 different problems. They both take in TWO oops which are both null-checked
71 independently before the using Node. After CCP removes the CastPP's they need
72 to pick up the guarding test edge - in this case TWO control edges. I tried
73 various solutions, all have problems:
75 (1) Do nothing. This leads to a bug where we hoist a Load from a CMoveP or a
76 StrComp above a guarding null check. I've seen both cases in normal -Xcomp
77 testing.
79 (2) Plug the control edge from 1 of the 2 oops in. Apparent problem here is
80 to figure out which test post-dominates. The real problem is that it doesn't
81 matter which one you pick. After you pick up, the dominating-test elider in
82 IGVN can remove the test and allow you to hoist up to the dominating test on
83 the chosen oop bypassing the test on the not-chosen oop. Seen in testing.
84 Oops.
86 (3) Leave the CastPP's in. This makes the graph more accurate in some sense;
87 we get to keep around the knowledge that an oop is not-null after some test.
88 Alas, the CastPP's interfere with GVN (some values are the regular oop, some
89 are the CastPP of the oop, all merge at Phi's which cannot collapse, etc).
90 This cost us 10% on SpecJVM, even when I removed some of the more trivial
91 cases in the optimizer. Removing more useless Phi's started allowing Loads to
92 illegally float above null checks. I gave up on this approach.
94 (4) Add BOTH control edges to both tests. Alas, too much code knows that
95 control edges are in slot-zero ONLY. Many quick asserts fail; no way to do
96 this one. Note that I really want to allow the CMoveP to float and add both
97 control edges to the dependent Load op - meaning I can select early but I
98 cannot Load until I pass both tests.
100 (5) Do not hoist CMoveP and StrComp. To this end I added the v-call
101 depends_only_on_test(). No obvious performance loss on Spec, but we are
102 clearly conservative on CMoveP (also so on StrComp but that's unlikely to
103 matter ever).
105 */
108 //------------------------------Ideal------------------------------------------
109 // Return a node which is more "ideal" than the current node.
110 // Move constants to the right.
111 Node *CMoveNode::Ideal(PhaseGVN *phase, bool can_reshape) {
112 if( in(0) && remove_dead_region(phase, can_reshape) ) return this;
113 // Don't bother trying to transform a dead node
114 if( in(0) && in(0)->is_top() ) return NULL;
115 assert( !phase->eqv(in(Condition), this) &&
116 !phase->eqv(in(IfFalse), this) &&
117 !phase->eqv(in(IfTrue), this), "dead loop in CMoveNode::Ideal" );
118 if( phase->type(in(Condition)) == Type::TOP )
119 return NULL; // return NULL when Condition is dead
121 if( in(IfFalse)->is_Con() && !in(IfTrue)->is_Con() ) {
122 if( in(Condition)->is_Bool() ) {
123 BoolNode* b = in(Condition)->as_Bool();
124 BoolNode* b2 = b->negate(phase);
125 return make( phase->C, in(Control), phase->transform(b2), in(IfTrue), in(IfFalse), _type );
126 }
127 }
128 return NULL;
129 }
131 //------------------------------is_cmove_id------------------------------------
132 // Helper function to check for CMOVE identity. Shared with PhiNode::Identity
133 Node *CMoveNode::is_cmove_id( PhaseTransform *phase, Node *cmp, Node *t, Node *f, BoolNode *b ) {
134 // Check for Cmp'ing and CMove'ing same values
135 if( (phase->eqv(cmp->in(1),f) &&
136 phase->eqv(cmp->in(2),t)) ||
137 // Swapped Cmp is OK
138 (phase->eqv(cmp->in(2),f) &&
139 phase->eqv(cmp->in(1),t)) ) {
140 // Give up this identity check for floating points because it may choose incorrect
141 // value around 0.0 and -0.0
142 if ( cmp->Opcode()==Op_CmpF || cmp->Opcode()==Op_CmpD )
143 return NULL;
144 // Check for "(t==f)?t:f;" and replace with "f"
145 if( b->_test._test == BoolTest::eq )
146 return f;
147 // Allow the inverted case as well
148 // Check for "(t!=f)?t:f;" and replace with "t"
149 if( b->_test._test == BoolTest::ne )
150 return t;
151 }
152 return NULL;
153 }
155 //------------------------------Identity---------------------------------------
156 // Conditional-move is an identity if both inputs are the same, or the test
157 // true or false.
158 Node *CMoveNode::Identity( PhaseTransform *phase ) {
159 if( phase->eqv(in(IfFalse),in(IfTrue)) ) // C-moving identical inputs?
160 return in(IfFalse); // Then it doesn't matter
161 if( phase->type(in(Condition)) == TypeInt::ZERO )
162 return in(IfFalse); // Always pick left(false) input
163 if( phase->type(in(Condition)) == TypeInt::ONE )
164 return in(IfTrue); // Always pick right(true) input
166 // Check for CMove'ing a constant after comparing against the constant.
167 // Happens all the time now, since if we compare equality vs a constant in
168 // the parser, we "know" the variable is constant on one path and we force
169 // it. Thus code like "if( x==0 ) {/*EMPTY*/}" ends up inserting a
170 // conditional move: "x = (x==0)?0:x;". Yucko. This fix is slightly more
171 // general in that we don't need constants.
172 if( in(Condition)->is_Bool() ) {
173 BoolNode *b = in(Condition)->as_Bool();
174 Node *cmp = b->in(1);
175 if( cmp->is_Cmp() ) {
176 Node *id = is_cmove_id( phase, cmp, in(IfTrue), in(IfFalse), b );
177 if( id ) return id;
178 }
179 }
181 return this;
182 }
184 //------------------------------Value------------------------------------------
185 // Result is the meet of inputs
186 const Type *CMoveNode::Value( PhaseTransform *phase ) const {
187 if( phase->type(in(Condition)) == Type::TOP )
188 return Type::TOP;
189 return phase->type(in(IfFalse))->meet(phase->type(in(IfTrue)));
190 }
192 //------------------------------make-------------------------------------------
193 // Make a correctly-flavored CMove. Since _type is directly determined
194 // from the inputs we do not need to specify it here.
195 CMoveNode *CMoveNode::make( Compile *C, Node *c, Node *bol, Node *left, Node *right, const Type *t ) {
196 switch( t->basic_type() ) {
197 case T_INT: return new (C, 4) CMoveINode( bol, left, right, t->is_int() );
198 case T_FLOAT: return new (C, 4) CMoveFNode( bol, left, right, t );
199 case T_DOUBLE: return new (C, 4) CMoveDNode( bol, left, right, t );
200 case T_LONG: return new (C, 4) CMoveLNode( bol, left, right, t->is_long() );
201 case T_OBJECT: return new (C, 4) CMovePNode( c, bol, left, right, t->is_oopptr() );
202 case T_ADDRESS: return new (C, 4) CMovePNode( c, bol, left, right, t->is_ptr() );
203 case T_NARROWOOP: return new (C, 4) CMoveNNode( c, bol, left, right, t );
204 default:
205 ShouldNotReachHere();
206 return NULL;
207 }
208 }
210 //=============================================================================
211 //------------------------------Ideal------------------------------------------
212 // Return a node which is more "ideal" than the current node.
213 // Check for conversions to boolean
214 Node *CMoveINode::Ideal(PhaseGVN *phase, bool can_reshape) {
215 // Try generic ideal's first
216 Node *x = CMoveNode::Ideal(phase, can_reshape);
217 if( x ) return x;
219 // If zero is on the left (false-case, no-move-case) it must mean another
220 // constant is on the right (otherwise the shared CMove::Ideal code would
221 // have moved the constant to the right). This situation is bad for Intel
222 // and a don't-care for Sparc. It's bad for Intel because the zero has to
223 // be manifested in a register with a XOR which kills flags, which are live
224 // on input to the CMoveI, leading to a situation which causes excessive
225 // spilling on Intel. For Sparc, if the zero in on the left the Sparc will
226 // zero a register via G0 and conditionally-move the other constant. If the
227 // zero is on the right, the Sparc will load the first constant with a
228 // 13-bit set-lo and conditionally move G0. See bug 4677505.
229 if( phase->type(in(IfFalse)) == TypeInt::ZERO && !(phase->type(in(IfTrue)) == TypeInt::ZERO) ) {
230 if( in(Condition)->is_Bool() ) {
231 BoolNode* b = in(Condition)->as_Bool();
232 BoolNode* b2 = b->negate(phase);
233 return make( phase->C, in(Control), phase->transform(b2), in(IfTrue), in(IfFalse), _type );
234 }
235 }
237 // Now check for booleans
238 int flip = 0;
240 // Check for picking from zero/one
241 if( phase->type(in(IfFalse)) == TypeInt::ZERO && phase->type(in(IfTrue)) == TypeInt::ONE ) {
242 flip = 1 - flip;
243 } else if( phase->type(in(IfFalse)) == TypeInt::ONE && phase->type(in(IfTrue)) == TypeInt::ZERO ) {
244 } else return NULL;
246 // Check for eq/ne test
247 if( !in(1)->is_Bool() ) return NULL;
248 BoolNode *bol = in(1)->as_Bool();
249 if( bol->_test._test == BoolTest::eq ) {
250 } else if( bol->_test._test == BoolTest::ne ) {
251 flip = 1-flip;
252 } else return NULL;
254 // Check for vs 0 or 1
255 if( !bol->in(1)->is_Cmp() ) return NULL;
256 const CmpNode *cmp = bol->in(1)->as_Cmp();
257 if( phase->type(cmp->in(2)) == TypeInt::ZERO ) {
258 } else if( phase->type(cmp->in(2)) == TypeInt::ONE ) {
259 // Allow cmp-vs-1 if the other input is bounded by 0-1
260 if( phase->type(cmp->in(1)) != TypeInt::BOOL )
261 return NULL;
262 flip = 1 - flip;
263 } else return NULL;
265 // Convert to a bool (flipped)
266 // Build int->bool conversion
267 #ifndef PRODUCT
268 if( PrintOpto ) tty->print_cr("CMOV to I2B");
269 #endif
270 Node *n = new (phase->C, 2) Conv2BNode( cmp->in(1) );
271 if( flip )
272 n = new (phase->C, 3) XorINode( phase->transform(n), phase->intcon(1) );
274 return n;
275 }
277 //=============================================================================
278 //------------------------------Ideal------------------------------------------
279 // Return a node which is more "ideal" than the current node.
280 // Check for absolute value
281 Node *CMoveFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
282 // Try generic ideal's first
283 Node *x = CMoveNode::Ideal(phase, can_reshape);
284 if( x ) return x;
286 int cmp_zero_idx = 0; // Index of compare input where to look for zero
287 int phi_x_idx = 0; // Index of phi input where to find naked x
289 // Find the Bool
290 if( !in(1)->is_Bool() ) return NULL;
291 BoolNode *bol = in(1)->as_Bool();
292 // Check bool sense
293 switch( bol->_test._test ) {
294 case BoolTest::lt: cmp_zero_idx = 1; phi_x_idx = IfTrue; break;
295 case BoolTest::le: cmp_zero_idx = 2; phi_x_idx = IfFalse; break;
296 case BoolTest::gt: cmp_zero_idx = 2; phi_x_idx = IfTrue; break;
297 case BoolTest::ge: cmp_zero_idx = 1; phi_x_idx = IfFalse; break;
298 default: return NULL; break;
299 }
301 // Find zero input of CmpF; the other input is being abs'd
302 Node *cmpf = bol->in(1);
303 if( cmpf->Opcode() != Op_CmpF ) return NULL;
304 Node *X = NULL;
305 bool flip = false;
306 if( phase->type(cmpf->in(cmp_zero_idx)) == TypeF::ZERO ) {
307 X = cmpf->in(3 - cmp_zero_idx);
308 } else if (phase->type(cmpf->in(3 - cmp_zero_idx)) == TypeF::ZERO) {
309 // The test is inverted, we should invert the result...
310 X = cmpf->in(cmp_zero_idx);
311 flip = true;
312 } else {
313 return NULL;
314 }
316 // If X is found on the appropriate phi input, find the subtract on the other
317 if( X != in(phi_x_idx) ) return NULL;
318 int phi_sub_idx = phi_x_idx == IfTrue ? IfFalse : IfTrue;
319 Node *sub = in(phi_sub_idx);
321 // Allow only SubF(0,X) and fail out for all others; NegF is not OK
322 if( sub->Opcode() != Op_SubF ||
323 sub->in(2) != X ||
324 phase->type(sub->in(1)) != TypeF::ZERO ) return NULL;
326 Node *abs = new (phase->C, 2) AbsFNode( X );
327 if( flip )
328 abs = new (phase->C, 3) SubFNode(sub->in(1), phase->transform(abs));
330 return abs;
331 }
333 //=============================================================================
334 //------------------------------Ideal------------------------------------------
335 // Return a node which is more "ideal" than the current node.
336 // Check for absolute value
337 Node *CMoveDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
338 // Try generic ideal's first
339 Node *x = CMoveNode::Ideal(phase, can_reshape);
340 if( x ) return x;
342 int cmp_zero_idx = 0; // Index of compare input where to look for zero
343 int phi_x_idx = 0; // Index of phi input where to find naked x
345 // Find the Bool
346 if( !in(1)->is_Bool() ) return NULL;
347 BoolNode *bol = in(1)->as_Bool();
348 // Check bool sense
349 switch( bol->_test._test ) {
350 case BoolTest::lt: cmp_zero_idx = 1; phi_x_idx = IfTrue; break;
351 case BoolTest::le: cmp_zero_idx = 2; phi_x_idx = IfFalse; break;
352 case BoolTest::gt: cmp_zero_idx = 2; phi_x_idx = IfTrue; break;
353 case BoolTest::ge: cmp_zero_idx = 1; phi_x_idx = IfFalse; break;
354 default: return NULL; break;
355 }
357 // Find zero input of CmpD; the other input is being abs'd
358 Node *cmpd = bol->in(1);
359 if( cmpd->Opcode() != Op_CmpD ) return NULL;
360 Node *X = NULL;
361 bool flip = false;
362 if( phase->type(cmpd->in(cmp_zero_idx)) == TypeD::ZERO ) {
363 X = cmpd->in(3 - cmp_zero_idx);
364 } else if (phase->type(cmpd->in(3 - cmp_zero_idx)) == TypeD::ZERO) {
365 // The test is inverted, we should invert the result...
366 X = cmpd->in(cmp_zero_idx);
367 flip = true;
368 } else {
369 return NULL;
370 }
372 // If X is found on the appropriate phi input, find the subtract on the other
373 if( X != in(phi_x_idx) ) return NULL;
374 int phi_sub_idx = phi_x_idx == IfTrue ? IfFalse : IfTrue;
375 Node *sub = in(phi_sub_idx);
377 // Allow only SubD(0,X) and fail out for all others; NegD is not OK
378 if( sub->Opcode() != Op_SubD ||
379 sub->in(2) != X ||
380 phase->type(sub->in(1)) != TypeD::ZERO ) return NULL;
382 Node *abs = new (phase->C, 2) AbsDNode( X );
383 if( flip )
384 abs = new (phase->C, 3) SubDNode(sub->in(1), phase->transform(abs));
386 return abs;
387 }
390 //=============================================================================
391 // If input is already higher or equal to cast type, then this is an identity.
392 Node *ConstraintCastNode::Identity( PhaseTransform *phase ) {
393 return phase->type(in(1))->higher_equal(_type) ? in(1) : this;
394 }
396 //------------------------------Value------------------------------------------
397 // Take 'join' of input and cast-up type
398 const Type *ConstraintCastNode::Value( PhaseTransform *phase ) const {
399 if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
400 const Type* ft = phase->type(in(1))->filter(_type);
402 #ifdef ASSERT
403 // Previous versions of this function had some special case logic,
404 // which is no longer necessary. Make sure of the required effects.
405 switch (Opcode()) {
406 case Op_CastII:
407 {
408 const Type* t1 = phase->type(in(1));
409 if( t1 == Type::TOP ) assert(ft == Type::TOP, "special case #1");
410 const Type* rt = t1->join(_type);
411 if (rt->empty()) assert(ft == Type::TOP, "special case #2");
412 break;
413 }
414 case Op_CastPP:
415 if (phase->type(in(1)) == TypePtr::NULL_PTR &&
416 _type->isa_ptr() && _type->is_ptr()->_ptr == TypePtr::NotNull)
417 assert(ft == Type::TOP, "special case #3");
418 break;
419 }
420 #endif //ASSERT
422 return ft;
423 }
425 //------------------------------Ideal------------------------------------------
426 // Return a node which is more "ideal" than the current node. Strip out
427 // control copies
428 Node *ConstraintCastNode::Ideal(PhaseGVN *phase, bool can_reshape){
429 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : NULL;
430 }
432 //------------------------------Ideal_DU_postCCP-------------------------------
433 // Throw away cast after constant propagation
434 Node *ConstraintCastNode::Ideal_DU_postCCP( PhaseCCP *ccp ) {
435 const Type *t = ccp->type(in(1));
436 ccp->hash_delete(this);
437 set_type(t); // Turn into ID function
438 ccp->hash_insert(this);
439 return this;
440 }
443 //=============================================================================
445 //------------------------------Ideal_DU_postCCP-------------------------------
446 // If not converting int->oop, throw away cast after constant propagation
447 Node *CastPPNode::Ideal_DU_postCCP( PhaseCCP *ccp ) {
448 const Type *t = ccp->type(in(1));
449 if (!t->isa_oop_ptr() || (in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks())) {
450 return NULL; // do not transform raw pointers or narrow oops
451 }
452 return ConstraintCastNode::Ideal_DU_postCCP(ccp);
453 }
457 //=============================================================================
458 //------------------------------Identity---------------------------------------
459 // If input is already higher or equal to cast type, then this is an identity.
460 Node *CheckCastPPNode::Identity( PhaseTransform *phase ) {
461 // Toned down to rescue meeting at a Phi 3 different oops all implementing
462 // the same interface. CompileTheWorld starting at 502, kd12rc1.zip.
463 return (phase->type(in(1)) == phase->type(this)) ? in(1) : this;
464 }
466 // Determine whether "n" is a node which can cause an alias of one of its inputs. Node types
467 // which can create aliases are: CheckCastPP, Phi, and any store (if there is also a load from
468 // the location.)
469 // Note: this checks for aliases created in this compilation, not ones which may
470 // be potentially created at call sites.
471 static bool can_cause_alias(Node *n, PhaseTransform *phase) {
472 bool possible_alias = false;
474 if (n->is_Store()) {
475 possible_alias = !n->as_Store()->value_never_loaded(phase);
476 } else {
477 int opc = n->Opcode();
478 possible_alias = n->is_Phi() ||
479 opc == Op_CheckCastPP ||
480 opc == Op_StorePConditional ||
481 opc == Op_CompareAndSwapP ||
482 opc == Op_CompareAndSwapN;
483 }
484 return possible_alias;
485 }
487 //------------------------------Value------------------------------------------
488 // Take 'join' of input and cast-up type, unless working with an Interface
489 const Type *CheckCastPPNode::Value( PhaseTransform *phase ) const {
490 if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
492 const Type *inn = phase->type(in(1));
493 if( inn == Type::TOP ) return Type::TOP; // No information yet
495 const TypePtr *in_type = inn->isa_ptr();
496 const TypePtr *my_type = _type->isa_ptr();
497 const Type *result = _type;
498 if( in_type != NULL && my_type != NULL ) {
499 TypePtr::PTR in_ptr = in_type->ptr();
500 if( in_ptr == TypePtr::Null ) {
501 result = in_type;
502 } else if( in_ptr == TypePtr::Constant ) {
503 // Casting a constant oop to an interface?
504 // (i.e., a String to a Comparable?)
505 // Then return the interface.
506 const TypeOopPtr *jptr = my_type->isa_oopptr();
507 assert( jptr, "" );
508 result = (jptr->klass()->is_interface() || !in_type->higher_equal(_type))
509 ? my_type->cast_to_ptr_type( TypePtr::NotNull )
510 : in_type;
511 } else {
512 result = my_type->cast_to_ptr_type( my_type->join_ptr(in_ptr) );
513 }
514 }
515 return result;
517 // JOIN NOT DONE HERE BECAUSE OF INTERFACE ISSUES.
518 // FIX THIS (DO THE JOIN) WHEN UNION TYPES APPEAR!
520 //
521 // Remove this code after overnight run indicates no performance
522 // loss from not performing JOIN at CheckCastPPNode
523 //
524 // const TypeInstPtr *in_oop = in->isa_instptr();
525 // const TypeInstPtr *my_oop = _type->isa_instptr();
526 // // If either input is an 'interface', return destination type
527 // assert (in_oop == NULL || in_oop->klass() != NULL, "");
528 // assert (my_oop == NULL || my_oop->klass() != NULL, "");
529 // if( (in_oop && in_oop->klass()->klass_part()->is_interface())
530 // ||(my_oop && my_oop->klass()->klass_part()->is_interface()) ) {
531 // TypePtr::PTR in_ptr = in->isa_ptr() ? in->is_ptr()->_ptr : TypePtr::BotPTR;
532 // // Preserve cast away nullness for interfaces
533 // if( in_ptr == TypePtr::NotNull && my_oop && my_oop->_ptr == TypePtr::BotPTR ) {
534 // return my_oop->cast_to_ptr_type(TypePtr::NotNull);
535 // }
536 // return _type;
537 // }
538 //
539 // // Neither the input nor the destination type is an interface,
540 //
541 // // history: JOIN used to cause weird corner case bugs
542 // // return (in == TypeOopPtr::NULL_PTR) ? in : _type;
543 // // JOIN picks up NotNull in common instance-of/check-cast idioms, both oops.
544 // // JOIN does not preserve NotNull in other cases, e.g. RawPtr vs InstPtr
545 // const Type *join = in->join(_type);
546 // // Check if join preserved NotNull'ness for pointers
547 // if( join->isa_ptr() && _type->isa_ptr() ) {
548 // TypePtr::PTR join_ptr = join->is_ptr()->_ptr;
549 // TypePtr::PTR type_ptr = _type->is_ptr()->_ptr;
550 // // If there isn't any NotNull'ness to preserve
551 // // OR if join preserved NotNull'ness then return it
552 // if( type_ptr == TypePtr::BotPTR || type_ptr == TypePtr::Null ||
553 // join_ptr == TypePtr::NotNull || join_ptr == TypePtr::Constant ) {
554 // return join;
555 // }
556 // // ELSE return same old type as before
557 // return _type;
558 // }
559 // // Not joining two pointers
560 // return join;
561 }
563 //------------------------------Ideal------------------------------------------
564 // Return a node which is more "ideal" than the current node. Strip out
565 // control copies
566 Node *CheckCastPPNode::Ideal(PhaseGVN *phase, bool can_reshape){
567 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : NULL;
568 }
571 Node* DecodeNNode::Identity(PhaseTransform* phase) {
572 const Type *t = phase->type( in(1) );
573 if( t == Type::TOP ) return in(1);
575 if (in(1)->is_EncodeP()) {
576 // (DecodeN (EncodeP p)) -> p
577 return in(1)->in(1);
578 }
579 return this;
580 }
582 const Type *DecodeNNode::Value( PhaseTransform *phase ) const {
583 const Type *t = phase->type( in(1) );
584 if (t == Type::TOP) return Type::TOP;
585 if (t == TypeNarrowOop::NULL_PTR) return TypePtr::NULL_PTR;
587 assert(t->isa_narrowoop(), "only narrowoop here");
588 return t->make_ptr();
589 }
591 Node* EncodePNode::Identity(PhaseTransform* phase) {
592 const Type *t = phase->type( in(1) );
593 if( t == Type::TOP ) return in(1);
595 if (in(1)->is_DecodeN()) {
596 // (EncodeP (DecodeN p)) -> p
597 return in(1)->in(1);
598 }
599 return this;
600 }
602 const Type *EncodePNode::Value( PhaseTransform *phase ) const {
603 const Type *t = phase->type( in(1) );
604 if (t == Type::TOP) return Type::TOP;
605 if (t == TypePtr::NULL_PTR) return TypeNarrowOop::NULL_PTR;
607 assert(t->isa_oopptr(), "only oopptr here");
608 return t->make_narrowoop();
609 }
612 Node *EncodePNode::Ideal_DU_postCCP( PhaseCCP *ccp ) {
613 return MemNode::Ideal_common_DU_postCCP(ccp, this, in(1));
614 }
616 //=============================================================================
617 //------------------------------Identity---------------------------------------
618 Node *Conv2BNode::Identity( PhaseTransform *phase ) {
619 const Type *t = phase->type( in(1) );
620 if( t == Type::TOP ) return in(1);
621 if( t == TypeInt::ZERO ) return in(1);
622 if( t == TypeInt::ONE ) return in(1);
623 if( t == TypeInt::BOOL ) return in(1);
624 return this;
625 }
627 //------------------------------Value------------------------------------------
628 const Type *Conv2BNode::Value( PhaseTransform *phase ) const {
629 const Type *t = phase->type( in(1) );
630 if( t == Type::TOP ) return Type::TOP;
631 if( t == TypeInt::ZERO ) return TypeInt::ZERO;
632 if( t == TypePtr::NULL_PTR ) return TypeInt::ZERO;
633 const TypePtr *tp = t->isa_ptr();
634 if( tp != NULL ) {
635 if( tp->ptr() == TypePtr::AnyNull ) return Type::TOP;
636 if( tp->ptr() == TypePtr::Constant) return TypeInt::ONE;
637 if (tp->ptr() == TypePtr::NotNull) return TypeInt::ONE;
638 return TypeInt::BOOL;
639 }
640 if (t->base() != Type::Int) return TypeInt::BOOL;
641 const TypeInt *ti = t->is_int();
642 if( ti->_hi < 0 || ti->_lo > 0 ) return TypeInt::ONE;
643 return TypeInt::BOOL;
644 }
647 // The conversions operations are all Alpha sorted. Please keep it that way!
648 //=============================================================================
649 //------------------------------Value------------------------------------------
650 const Type *ConvD2FNode::Value( PhaseTransform *phase ) const {
651 const Type *t = phase->type( in(1) );
652 if( t == Type::TOP ) return Type::TOP;
653 if( t == Type::DOUBLE ) return Type::FLOAT;
654 const TypeD *td = t->is_double_constant();
655 return TypeF::make( (float)td->getd() );
656 }
658 //------------------------------Identity---------------------------------------
659 // Float's can be converted to doubles with no loss of bits. Hence
660 // converting a float to a double and back to a float is a NOP.
661 Node *ConvD2FNode::Identity(PhaseTransform *phase) {
662 return (in(1)->Opcode() == Op_ConvF2D) ? in(1)->in(1) : this;
663 }
665 //=============================================================================
666 //------------------------------Value------------------------------------------
667 const Type *ConvD2INode::Value( PhaseTransform *phase ) const {
668 const Type *t = phase->type( in(1) );
669 if( t == Type::TOP ) return Type::TOP;
670 if( t == Type::DOUBLE ) return TypeInt::INT;
671 const TypeD *td = t->is_double_constant();
672 return TypeInt::make( SharedRuntime::d2i( td->getd() ) );
673 }
675 //------------------------------Ideal------------------------------------------
676 // If converting to an int type, skip any rounding nodes
677 Node *ConvD2INode::Ideal(PhaseGVN *phase, bool can_reshape) {
678 if( in(1)->Opcode() == Op_RoundDouble )
679 set_req(1,in(1)->in(1));
680 return NULL;
681 }
683 //------------------------------Identity---------------------------------------
684 // Int's can be converted to doubles with no loss of bits. Hence
685 // converting an integer to a double and back to an integer is a NOP.
686 Node *ConvD2INode::Identity(PhaseTransform *phase) {
687 return (in(1)->Opcode() == Op_ConvI2D) ? in(1)->in(1) : this;
688 }
690 //=============================================================================
691 //------------------------------Value------------------------------------------
692 const Type *ConvD2LNode::Value( PhaseTransform *phase ) const {
693 const Type *t = phase->type( in(1) );
694 if( t == Type::TOP ) return Type::TOP;
695 if( t == Type::DOUBLE ) return TypeLong::LONG;
696 const TypeD *td = t->is_double_constant();
697 return TypeLong::make( SharedRuntime::d2l( td->getd() ) );
698 }
700 //------------------------------Identity---------------------------------------
701 Node *ConvD2LNode::Identity(PhaseTransform *phase) {
702 // Remove ConvD2L->ConvL2D->ConvD2L sequences.
703 if( in(1) ->Opcode() == Op_ConvL2D &&
704 in(1)->in(1)->Opcode() == Op_ConvD2L )
705 return in(1)->in(1);
706 return this;
707 }
709 //------------------------------Ideal------------------------------------------
710 // If converting to an int type, skip any rounding nodes
711 Node *ConvD2LNode::Ideal(PhaseGVN *phase, bool can_reshape) {
712 if( in(1)->Opcode() == Op_RoundDouble )
713 set_req(1,in(1)->in(1));
714 return NULL;
715 }
717 //=============================================================================
718 //------------------------------Value------------------------------------------
719 const Type *ConvF2DNode::Value( PhaseTransform *phase ) const {
720 const Type *t = phase->type( in(1) );
721 if( t == Type::TOP ) return Type::TOP;
722 if( t == Type::FLOAT ) return Type::DOUBLE;
723 const TypeF *tf = t->is_float_constant();
724 return TypeD::make( (double)tf->getf() );
725 }
727 //=============================================================================
728 //------------------------------Value------------------------------------------
729 const Type *ConvF2INode::Value( PhaseTransform *phase ) const {
730 const Type *t = phase->type( in(1) );
731 if( t == Type::TOP ) return Type::TOP;
732 if( t == Type::FLOAT ) return TypeInt::INT;
733 const TypeF *tf = t->is_float_constant();
734 return TypeInt::make( SharedRuntime::f2i( tf->getf() ) );
735 }
737 //------------------------------Identity---------------------------------------
738 Node *ConvF2INode::Identity(PhaseTransform *phase) {
739 // Remove ConvF2I->ConvI2F->ConvF2I sequences.
740 if( in(1) ->Opcode() == Op_ConvI2F &&
741 in(1)->in(1)->Opcode() == Op_ConvF2I )
742 return in(1)->in(1);
743 return this;
744 }
746 //------------------------------Ideal------------------------------------------
747 // If converting to an int type, skip any rounding nodes
748 Node *ConvF2INode::Ideal(PhaseGVN *phase, bool can_reshape) {
749 if( in(1)->Opcode() == Op_RoundFloat )
750 set_req(1,in(1)->in(1));
751 return NULL;
752 }
754 //=============================================================================
755 //------------------------------Value------------------------------------------
756 const Type *ConvF2LNode::Value( PhaseTransform *phase ) const {
757 const Type *t = phase->type( in(1) );
758 if( t == Type::TOP ) return Type::TOP;
759 if( t == Type::FLOAT ) return TypeLong::LONG;
760 const TypeF *tf = t->is_float_constant();
761 return TypeLong::make( SharedRuntime::f2l( tf->getf() ) );
762 }
764 //------------------------------Identity---------------------------------------
765 Node *ConvF2LNode::Identity(PhaseTransform *phase) {
766 // Remove ConvF2L->ConvL2F->ConvF2L sequences.
767 if( in(1) ->Opcode() == Op_ConvL2F &&
768 in(1)->in(1)->Opcode() == Op_ConvF2L )
769 return in(1)->in(1);
770 return this;
771 }
773 //------------------------------Ideal------------------------------------------
774 // If converting to an int type, skip any rounding nodes
775 Node *ConvF2LNode::Ideal(PhaseGVN *phase, bool can_reshape) {
776 if( in(1)->Opcode() == Op_RoundFloat )
777 set_req(1,in(1)->in(1));
778 return NULL;
779 }
781 //=============================================================================
782 //------------------------------Value------------------------------------------
783 const Type *ConvI2DNode::Value( PhaseTransform *phase ) const {
784 const Type *t = phase->type( in(1) );
785 if( t == Type::TOP ) return Type::TOP;
786 const TypeInt *ti = t->is_int();
787 if( ti->is_con() ) return TypeD::make( (double)ti->get_con() );
788 return bottom_type();
789 }
791 //=============================================================================
792 //------------------------------Value------------------------------------------
793 const Type *ConvI2FNode::Value( PhaseTransform *phase ) const {
794 const Type *t = phase->type( in(1) );
795 if( t == Type::TOP ) return Type::TOP;
796 const TypeInt *ti = t->is_int();
797 if( ti->is_con() ) return TypeF::make( (float)ti->get_con() );
798 return bottom_type();
799 }
801 //------------------------------Identity---------------------------------------
802 Node *ConvI2FNode::Identity(PhaseTransform *phase) {
803 // Remove ConvI2F->ConvF2I->ConvI2F sequences.
804 if( in(1) ->Opcode() == Op_ConvF2I &&
805 in(1)->in(1)->Opcode() == Op_ConvI2F )
806 return in(1)->in(1);
807 return this;
808 }
810 //=============================================================================
811 //------------------------------Value------------------------------------------
812 const Type *ConvI2LNode::Value( PhaseTransform *phase ) const {
813 const Type *t = phase->type( in(1) );
814 if( t == Type::TOP ) return Type::TOP;
815 const TypeInt *ti = t->is_int();
816 const Type* tl = TypeLong::make(ti->_lo, ti->_hi, ti->_widen);
817 // Join my declared type against my incoming type.
818 tl = tl->filter(_type);
819 return tl;
820 }
822 #ifdef _LP64
823 static inline bool long_ranges_overlap(jlong lo1, jlong hi1,
824 jlong lo2, jlong hi2) {
825 // Two ranges overlap iff one range's low point falls in the other range.
826 return (lo2 <= lo1 && lo1 <= hi2) || (lo1 <= lo2 && lo2 <= hi1);
827 }
828 #endif
830 //------------------------------Ideal------------------------------------------
831 Node *ConvI2LNode::Ideal(PhaseGVN *phase, bool can_reshape) {
832 const TypeLong* this_type = this->type()->is_long();
833 Node* this_changed = NULL;
835 // If _major_progress, then more loop optimizations follow. Do NOT
836 // remove this node's type assertion until no more loop ops can happen.
837 // The progress bit is set in the major loop optimizations THEN comes the
838 // call to IterGVN and any chance of hitting this code. Cf. Opaque1Node.
839 if (can_reshape && !phase->C->major_progress()) {
840 const TypeInt* in_type = phase->type(in(1))->isa_int();
841 if (in_type != NULL && this_type != NULL &&
842 (in_type->_lo != this_type->_lo ||
843 in_type->_hi != this_type->_hi)) {
844 // Although this WORSENS the type, it increases GVN opportunities,
845 // because I2L nodes with the same input will common up, regardless
846 // of slightly differing type assertions. Such slight differences
847 // arise routinely as a result of loop unrolling, so this is a
848 // post-unrolling graph cleanup. Choose a type which depends only
849 // on my input. (Exception: Keep a range assertion of >=0 or <0.)
850 jlong lo1 = this_type->_lo;
851 jlong hi1 = this_type->_hi;
852 int w1 = this_type->_widen;
853 if (lo1 != (jint)lo1 ||
854 hi1 != (jint)hi1 ||
855 lo1 > hi1) {
856 // Overflow leads to wraparound, wraparound leads to range saturation.
857 lo1 = min_jint; hi1 = max_jint;
858 } else if (lo1 >= 0) {
859 // Keep a range assertion of >=0.
860 lo1 = 0; hi1 = max_jint;
861 } else if (hi1 < 0) {
862 // Keep a range assertion of <0.
863 lo1 = min_jint; hi1 = -1;
864 } else {
865 lo1 = min_jint; hi1 = max_jint;
866 }
867 const TypeLong* wtype = TypeLong::make(MAX2((jlong)in_type->_lo, lo1),
868 MIN2((jlong)in_type->_hi, hi1),
869 MAX2((int)in_type->_widen, w1));
870 if (wtype != type()) {
871 set_type(wtype);
872 // Note: this_type still has old type value, for the logic below.
873 this_changed = this;
874 }
875 }
876 }
878 #ifdef _LP64
879 // Convert ConvI2L(AddI(x, y)) to AddL(ConvI2L(x), ConvI2L(y)) ,
880 // but only if x and y have subranges that cannot cause 32-bit overflow,
881 // under the assumption that x+y is in my own subrange this->type().
883 // This assumption is based on a constraint (i.e., type assertion)
884 // established in Parse::array_addressing or perhaps elsewhere.
885 // This constraint has been adjoined to the "natural" type of
886 // the incoming argument in(0). We know (because of runtime
887 // checks) - that the result value I2L(x+y) is in the joined range.
888 // Hence we can restrict the incoming terms (x, y) to values such
889 // that their sum also lands in that range.
891 // This optimization is useful only on 64-bit systems, where we hope
892 // the addition will end up subsumed in an addressing mode.
893 // It is necessary to do this when optimizing an unrolled array
894 // copy loop such as x[i++] = y[i++].
896 // On 32-bit systems, it's better to perform as much 32-bit math as
897 // possible before the I2L conversion, because 32-bit math is cheaper.
898 // There's no common reason to "leak" a constant offset through the I2L.
899 // Addressing arithmetic will not absorb it as part of a 64-bit AddL.
901 Node* z = in(1);
902 int op = z->Opcode();
903 if (op == Op_AddI || op == Op_SubI) {
904 Node* x = z->in(1);
905 Node* y = z->in(2);
906 assert (x != z && y != z, "dead loop in ConvI2LNode::Ideal");
907 if (phase->type(x) == Type::TOP) return this_changed;
908 if (phase->type(y) == Type::TOP) return this_changed;
909 const TypeInt* tx = phase->type(x)->is_int();
910 const TypeInt* ty = phase->type(y)->is_int();
911 const TypeLong* tz = this_type;
912 jlong xlo = tx->_lo;
913 jlong xhi = tx->_hi;
914 jlong ylo = ty->_lo;
915 jlong yhi = ty->_hi;
916 jlong zlo = tz->_lo;
917 jlong zhi = tz->_hi;
918 jlong vbit = CONST64(1) << BitsPerInt;
919 int widen = MAX2(tx->_widen, ty->_widen);
920 if (op == Op_SubI) {
921 jlong ylo0 = ylo;
922 ylo = -yhi;
923 yhi = -ylo0;
924 }
925 // See if x+y can cause positive overflow into z+2**32
926 if (long_ranges_overlap(xlo+ylo, xhi+yhi, zlo+vbit, zhi+vbit)) {
927 return this_changed;
928 }
929 // See if x+y can cause negative overflow into z-2**32
930 if (long_ranges_overlap(xlo+ylo, xhi+yhi, zlo-vbit, zhi-vbit)) {
931 return this_changed;
932 }
933 // Now it's always safe to assume x+y does not overflow.
934 // This is true even if some pairs x,y might cause overflow, as long
935 // as that overflow value cannot fall into [zlo,zhi].
937 // Confident that the arithmetic is "as if infinite precision",
938 // we can now use z's range to put constraints on those of x and y.
939 // The "natural" range of x [xlo,xhi] can perhaps be narrowed to a
940 // more "restricted" range by intersecting [xlo,xhi] with the
941 // range obtained by subtracting y's range from the asserted range
942 // of the I2L conversion. Here's the interval arithmetic algebra:
943 // x == z-y == [zlo,zhi]-[ylo,yhi] == [zlo,zhi]+[-yhi,-ylo]
944 // => x in [zlo-yhi, zhi-ylo]
945 // => x in [zlo-yhi, zhi-ylo] INTERSECT [xlo,xhi]
946 // => x in [xlo MAX zlo-yhi, xhi MIN zhi-ylo]
947 jlong rxlo = MAX2(xlo, zlo - yhi);
948 jlong rxhi = MIN2(xhi, zhi - ylo);
949 // And similarly, x changing place with y:
950 jlong rylo = MAX2(ylo, zlo - xhi);
951 jlong ryhi = MIN2(yhi, zhi - xlo);
952 if (rxlo > rxhi || rylo > ryhi) {
953 return this_changed; // x or y is dying; don't mess w/ it
954 }
955 if (op == Op_SubI) {
956 jlong rylo0 = rylo;
957 rylo = -ryhi;
958 ryhi = -rylo0;
959 }
961 Node* cx = phase->transform( new (phase->C, 2) ConvI2LNode(x, TypeLong::make(rxlo, rxhi, widen)) );
962 Node* cy = phase->transform( new (phase->C, 2) ConvI2LNode(y, TypeLong::make(rylo, ryhi, widen)) );
963 switch (op) {
964 case Op_AddI: return new (phase->C, 3) AddLNode(cx, cy);
965 case Op_SubI: return new (phase->C, 3) SubLNode(cx, cy);
966 default: ShouldNotReachHere();
967 }
968 }
969 #endif //_LP64
971 return this_changed;
972 }
974 //=============================================================================
975 //------------------------------Value------------------------------------------
976 const Type *ConvL2DNode::Value( PhaseTransform *phase ) const {
977 const Type *t = phase->type( in(1) );
978 if( t == Type::TOP ) return Type::TOP;
979 const TypeLong *tl = t->is_long();
980 if( tl->is_con() ) return TypeD::make( (double)tl->get_con() );
981 return bottom_type();
982 }
984 //=============================================================================
985 //------------------------------Value------------------------------------------
986 const Type *ConvL2FNode::Value( PhaseTransform *phase ) const {
987 const Type *t = phase->type( in(1) );
988 if( t == Type::TOP ) return Type::TOP;
989 const TypeLong *tl = t->is_long();
990 if( tl->is_con() ) return TypeF::make( (float)tl->get_con() );
991 return bottom_type();
992 }
994 //=============================================================================
995 //----------------------------Identity-----------------------------------------
996 Node *ConvL2INode::Identity( PhaseTransform *phase ) {
997 // Convert L2I(I2L(x)) => x
998 if (in(1)->Opcode() == Op_ConvI2L) return in(1)->in(1);
999 return this;
1000 }
1002 //------------------------------Value------------------------------------------
1003 const Type *ConvL2INode::Value( PhaseTransform *phase ) const {
1004 const Type *t = phase->type( in(1) );
1005 if( t == Type::TOP ) return Type::TOP;
1006 const TypeLong *tl = t->is_long();
1007 if (tl->is_con())
1008 // Easy case.
1009 return TypeInt::make((jint)tl->get_con());
1010 return bottom_type();
1011 }
1013 //------------------------------Ideal------------------------------------------
1014 // Return a node which is more "ideal" than the current node.
1015 // Blow off prior masking to int
1016 Node *ConvL2INode::Ideal(PhaseGVN *phase, bool can_reshape) {
1017 Node *andl = in(1);
1018 uint andl_op = andl->Opcode();
1019 if( andl_op == Op_AndL ) {
1020 // Blow off prior masking to int
1021 if( phase->type(andl->in(2)) == TypeLong::make( 0xFFFFFFFF ) ) {
1022 set_req(1,andl->in(1));
1023 return this;
1024 }
1025 }
1027 // Swap with a prior add: convL2I(addL(x,y)) ==> addI(convL2I(x),convL2I(y))
1028 // This replaces an 'AddL' with an 'AddI'.
1029 if( andl_op == Op_AddL ) {
1030 // Don't do this for nodes which have more than one user since
1031 // we'll end up computing the long add anyway.
1032 if (andl->outcnt() > 1) return NULL;
1034 Node* x = andl->in(1);
1035 Node* y = andl->in(2);
1036 assert( x != andl && y != andl, "dead loop in ConvL2INode::Ideal" );
1037 if (phase->type(x) == Type::TOP) return NULL;
1038 if (phase->type(y) == Type::TOP) return NULL;
1039 Node *add1 = phase->transform(new (phase->C, 2) ConvL2INode(x));
1040 Node *add2 = phase->transform(new (phase->C, 2) ConvL2INode(y));
1041 return new (phase->C, 3) AddINode(add1,add2);
1042 }
1044 // Disable optimization: LoadL->ConvL2I ==> LoadI.
1045 // It causes problems (sizes of Load and Store nodes do not match)
1046 // in objects initialization code and Escape Analysis.
1047 return NULL;
1048 }
1050 //=============================================================================
1051 //------------------------------Value------------------------------------------
1052 const Type *CastX2PNode::Value( PhaseTransform *phase ) const {
1053 const Type* t = phase->type(in(1));
1054 if (t->base() == Type_X && t->singleton()) {
1055 uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con();
1056 if (bits == 0) return TypePtr::NULL_PTR;
1057 return TypeRawPtr::make((address) bits);
1058 }
1059 return CastX2PNode::bottom_type();
1060 }
1062 //------------------------------Idealize---------------------------------------
1063 static inline bool fits_in_int(const Type* t, bool but_not_min_int = false) {
1064 if (t == Type::TOP) return false;
1065 const TypeX* tl = t->is_intptr_t();
1066 jint lo = min_jint;
1067 jint hi = max_jint;
1068 if (but_not_min_int) ++lo; // caller wants to negate the value w/o overflow
1069 return (tl->_lo >= lo) && (tl->_hi <= hi);
1070 }
1072 static inline Node* addP_of_X2P(PhaseGVN *phase,
1073 Node* base,
1074 Node* dispX,
1075 bool negate = false) {
1076 if (negate) {
1077 dispX = new (phase->C, 3) SubXNode(phase->MakeConX(0), phase->transform(dispX));
1078 }
1079 return new (phase->C, 4) AddPNode(phase->C->top(),
1080 phase->transform(new (phase->C, 2) CastX2PNode(base)),
1081 phase->transform(dispX));
1082 }
1084 Node *CastX2PNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1085 // convert CastX2P(AddX(x, y)) to AddP(CastX2P(x), y) if y fits in an int
1086 int op = in(1)->Opcode();
1087 Node* x;
1088 Node* y;
1089 switch (op) {
1090 case Op_SubX:
1091 x = in(1)->in(1);
1092 // Avoid ideal transformations ping-pong between this and AddP for raw pointers.
1093 if (phase->find_intptr_t_con(x, -1) == 0)
1094 break;
1095 y = in(1)->in(2);
1096 if (fits_in_int(phase->type(y), true)) {
1097 return addP_of_X2P(phase, x, y, true);
1098 }
1099 break;
1100 case Op_AddX:
1101 x = in(1)->in(1);
1102 y = in(1)->in(2);
1103 if (fits_in_int(phase->type(y))) {
1104 return addP_of_X2P(phase, x, y);
1105 }
1106 if (fits_in_int(phase->type(x))) {
1107 return addP_of_X2P(phase, y, x);
1108 }
1109 break;
1110 }
1111 return NULL;
1112 }
1114 //------------------------------Identity---------------------------------------
1115 Node *CastX2PNode::Identity( PhaseTransform *phase ) {
1116 if (in(1)->Opcode() == Op_CastP2X) return in(1)->in(1);
1117 return this;
1118 }
1120 //=============================================================================
1121 //------------------------------Value------------------------------------------
1122 const Type *CastP2XNode::Value( PhaseTransform *phase ) const {
1123 const Type* t = phase->type(in(1));
1124 if (t->base() == Type::RawPtr && t->singleton()) {
1125 uintptr_t bits = (uintptr_t) t->is_rawptr()->get_con();
1126 return TypeX::make(bits);
1127 }
1128 return CastP2XNode::bottom_type();
1129 }
1131 Node *CastP2XNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1132 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : NULL;
1133 }
1135 //------------------------------Identity---------------------------------------
1136 Node *CastP2XNode::Identity( PhaseTransform *phase ) {
1137 if (in(1)->Opcode() == Op_CastX2P) return in(1)->in(1);
1138 return this;
1139 }
1142 //=============================================================================
1143 //------------------------------Identity---------------------------------------
1144 // Remove redundant roundings
1145 Node *RoundFloatNode::Identity( PhaseTransform *phase ) {
1146 assert(Matcher::strict_fp_requires_explicit_rounding, "should only generate for Intel");
1147 // Do not round constants
1148 if (phase->type(in(1))->base() == Type::FloatCon) return in(1);
1149 int op = in(1)->Opcode();
1150 // Redundant rounding
1151 if( op == Op_RoundFloat ) return in(1);
1152 // Already rounded
1153 if( op == Op_Parm ) return in(1);
1154 if( op == Op_LoadF ) return in(1);
1155 return this;
1156 }
1158 //------------------------------Value------------------------------------------
1159 const Type *RoundFloatNode::Value( PhaseTransform *phase ) const {
1160 return phase->type( in(1) );
1161 }
1163 //=============================================================================
1164 //------------------------------Identity---------------------------------------
1165 // Remove redundant roundings. Incoming arguments are already rounded.
1166 Node *RoundDoubleNode::Identity( PhaseTransform *phase ) {
1167 assert(Matcher::strict_fp_requires_explicit_rounding, "should only generate for Intel");
1168 // Do not round constants
1169 if (phase->type(in(1))->base() == Type::DoubleCon) return in(1);
1170 int op = in(1)->Opcode();
1171 // Redundant rounding
1172 if( op == Op_RoundDouble ) return in(1);
1173 // Already rounded
1174 if( op == Op_Parm ) return in(1);
1175 if( op == Op_LoadD ) return in(1);
1176 if( op == Op_ConvF2D ) return in(1);
1177 if( op == Op_ConvI2D ) return in(1);
1178 return this;
1179 }
1181 //------------------------------Value------------------------------------------
1182 const Type *RoundDoubleNode::Value( PhaseTransform *phase ) const {
1183 return phase->type( in(1) );
1184 }
1187 //=============================================================================
1188 // Do not allow value-numbering
1189 uint Opaque1Node::hash() const { return NO_HASH; }
1190 uint Opaque1Node::cmp( const Node &n ) const {
1191 return (&n == this); // Always fail except on self
1192 }
1194 //------------------------------Identity---------------------------------------
1195 // If _major_progress, then more loop optimizations follow. Do NOT remove
1196 // the opaque Node until no more loop ops can happen. Note the timing of
1197 // _major_progress; it's set in the major loop optimizations THEN comes the
1198 // call to IterGVN and any chance of hitting this code. Hence there's no
1199 // phase-ordering problem with stripping Opaque1 in IGVN followed by some
1200 // more loop optimizations that require it.
1201 Node *Opaque1Node::Identity( PhaseTransform *phase ) {
1202 return phase->C->major_progress() ? this : in(1);
1203 }
1205 //=============================================================================
1206 // A node to prevent unwanted optimizations. Allows constant folding. Stops
1207 // value-numbering, most Ideal calls or Identity functions. This Node is
1208 // specifically designed to prevent the pre-increment value of a loop trip
1209 // counter from being live out of the bottom of the loop (hence causing the
1210 // pre- and post-increment values both being live and thus requiring an extra
1211 // temp register and an extra move). If we "accidentally" optimize through
1212 // this kind of a Node, we'll get slightly pessimal, but correct, code. Thus
1213 // it's OK to be slightly sloppy on optimizations here.
1215 // Do not allow value-numbering
1216 uint Opaque2Node::hash() const { return NO_HASH; }
1217 uint Opaque2Node::cmp( const Node &n ) const {
1218 return (&n == this); // Always fail except on self
1219 }
1222 //------------------------------Value------------------------------------------
1223 const Type *MoveL2DNode::Value( PhaseTransform *phase ) const {
1224 const Type *t = phase->type( in(1) );
1225 if( t == Type::TOP ) return Type::TOP;
1226 const TypeLong *tl = t->is_long();
1227 if( !tl->is_con() ) return bottom_type();
1228 JavaValue v;
1229 v.set_jlong(tl->get_con());
1230 return TypeD::make( v.get_jdouble() );
1231 }
1233 //------------------------------Value------------------------------------------
1234 const Type *MoveI2FNode::Value( PhaseTransform *phase ) const {
1235 const Type *t = phase->type( in(1) );
1236 if( t == Type::TOP ) return Type::TOP;
1237 const TypeInt *ti = t->is_int();
1238 if( !ti->is_con() ) return bottom_type();
1239 JavaValue v;
1240 v.set_jint(ti->get_con());
1241 return TypeF::make( v.get_jfloat() );
1242 }
1244 //------------------------------Value------------------------------------------
1245 const Type *MoveF2INode::Value( PhaseTransform *phase ) const {
1246 const Type *t = phase->type( in(1) );
1247 if( t == Type::TOP ) return Type::TOP;
1248 if( t == Type::FLOAT ) return TypeInt::INT;
1249 const TypeF *tf = t->is_float_constant();
1250 JavaValue v;
1251 v.set_jfloat(tf->getf());
1252 return TypeInt::make( v.get_jint() );
1253 }
1255 //------------------------------Value------------------------------------------
1256 const Type *MoveD2LNode::Value( PhaseTransform *phase ) const {
1257 const Type *t = phase->type( in(1) );
1258 if( t == Type::TOP ) return Type::TOP;
1259 if( t == Type::DOUBLE ) return TypeLong::LONG;
1260 const TypeD *td = t->is_double_constant();
1261 JavaValue v;
1262 v.set_jdouble(td->getd());
1263 return TypeLong::make( v.get_jlong() );
1264 }
1266 //------------------------------Value------------------------------------------
1267 const Type* CountLeadingZerosINode::Value(PhaseTransform* phase) const {
1268 const Type* t = phase->type(in(1));
1269 if (t == Type::TOP) return Type::TOP;
1270 const TypeInt* ti = t->isa_int();
1271 if (ti && ti->is_con()) {
1272 jint i = ti->get_con();
1273 // HD, Figure 5-6
1274 if (i == 0)
1275 return TypeInt::make(BitsPerInt);
1276 int n = 1;
1277 unsigned int x = i;
1278 if (x >> 16 == 0) { n += 16; x <<= 16; }
1279 if (x >> 24 == 0) { n += 8; x <<= 8; }
1280 if (x >> 28 == 0) { n += 4; x <<= 4; }
1281 if (x >> 30 == 0) { n += 2; x <<= 2; }
1282 n -= x >> 31;
1283 return TypeInt::make(n);
1284 }
1285 return TypeInt::INT;
1286 }
1288 //------------------------------Value------------------------------------------
1289 const Type* CountLeadingZerosLNode::Value(PhaseTransform* phase) const {
1290 const Type* t = phase->type(in(1));
1291 if (t == Type::TOP) return Type::TOP;
1292 const TypeLong* tl = t->isa_long();
1293 if (tl && tl->is_con()) {
1294 jlong l = tl->get_con();
1295 // HD, Figure 5-6
1296 if (l == 0)
1297 return TypeInt::make(BitsPerLong);
1298 int n = 1;
1299 unsigned int x = (((julong) l) >> 32);
1300 if (x == 0) { n += 32; x = (int) l; }
1301 if (x >> 16 == 0) { n += 16; x <<= 16; }
1302 if (x >> 24 == 0) { n += 8; x <<= 8; }
1303 if (x >> 28 == 0) { n += 4; x <<= 4; }
1304 if (x >> 30 == 0) { n += 2; x <<= 2; }
1305 n -= x >> 31;
1306 return TypeInt::make(n);
1307 }
1308 return TypeInt::INT;
1309 }
1311 //------------------------------Value------------------------------------------
1312 const Type* CountTrailingZerosINode::Value(PhaseTransform* phase) const {
1313 const Type* t = phase->type(in(1));
1314 if (t == Type::TOP) return Type::TOP;
1315 const TypeInt* ti = t->isa_int();
1316 if (ti && ti->is_con()) {
1317 jint i = ti->get_con();
1318 // HD, Figure 5-14
1319 int y;
1320 if (i == 0)
1321 return TypeInt::make(BitsPerInt);
1322 int n = 31;
1323 y = i << 16; if (y != 0) { n = n - 16; i = y; }
1324 y = i << 8; if (y != 0) { n = n - 8; i = y; }
1325 y = i << 4; if (y != 0) { n = n - 4; i = y; }
1326 y = i << 2; if (y != 0) { n = n - 2; i = y; }
1327 y = i << 1; if (y != 0) { n = n - 1; }
1328 return TypeInt::make(n);
1329 }
1330 return TypeInt::INT;
1331 }
1333 //------------------------------Value------------------------------------------
1334 const Type* CountTrailingZerosLNode::Value(PhaseTransform* phase) const {
1335 const Type* t = phase->type(in(1));
1336 if (t == Type::TOP) return Type::TOP;
1337 const TypeLong* tl = t->isa_long();
1338 if (tl && tl->is_con()) {
1339 jlong l = tl->get_con();
1340 // HD, Figure 5-14
1341 int x, y;
1342 if (l == 0)
1343 return TypeInt::make(BitsPerLong);
1344 int n = 63;
1345 y = (int) l; if (y != 0) { n = n - 32; x = y; } else x = (((julong) l) >> 32);
1346 y = x << 16; if (y != 0) { n = n - 16; x = y; }
1347 y = x << 8; if (y != 0) { n = n - 8; x = y; }
1348 y = x << 4; if (y != 0) { n = n - 4; x = y; }
1349 y = x << 2; if (y != 0) { n = n - 2; x = y; }
1350 y = x << 1; if (y != 0) { n = n - 1; }
1351 return TypeInt::make(n);
1352 }
1353 return TypeInt::INT;
1354 }