1 /*
2 * Copyright (c) 1997, 2009, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 // Portions of code courtesy of Clifford Click
26
27 #include "incls/_precompiled.incl"
28 #include "incls/_addnode.cpp.incl"
29
30 #define MAXFLOAT ((float)3.40282346638528860e+38)
31
32 // Classic Add functionality. This covers all the usual 'add' behaviors for
33 // an algebraic ring. Add-integer, add-float, add-double, and binary-or are
34 // all inherited from this class. The various identity values are supplied
35 // by virtual functions.
36
37
38 //=============================================================================
39 //------------------------------hash-------------------------------------------
40 // Hash function over AddNodes. Needs to be commutative; i.e., I swap
41 // (commute) inputs to AddNodes willy-nilly so the hash function must return
42 // the same value in the presence of edge swapping.
43 uint AddNode::hash() const {
44 return (uintptr_t)in(1) + (uintptr_t)in(2) + Opcode();
45 }
46
47 //------------------------------Identity---------------------------------------
48 // If either input is a constant 0, return the other input.
49 Node *AddNode::Identity( PhaseTransform *phase ) {
50 const Type *zero = add_id(); // The additive identity
51 if( phase->type( in(1) )->higher_equal( zero ) ) return in(2);
52 if( phase->type( in(2) )->higher_equal( zero ) ) return in(1);
53 return this;
54 }
55
56 //------------------------------commute----------------------------------------
57 // Commute operands to move loads and constants to the right.
58 static bool commute( Node *add, int con_left, int con_right ) {
59 Node *in1 = add->in(1);
60 Node *in2 = add->in(2);
61
62 // Convert "1+x" into "x+1".
63 // Right is a constant; leave it
64 if( con_right ) return false;
65 // Left is a constant; move it right.
66 if( con_left ) {
67 add->swap_edges(1, 2);
68 return true;
69 }
70
71 // Convert "Load+x" into "x+Load".
72 // Now check for loads
73 if (in2->is_Load()) {
74 if (!in1->is_Load()) {
75 // already x+Load to return
76 return false;
77 }
78 // both are loads, so fall through to sort inputs by idx
79 } else if( in1->is_Load() ) {
80 // Left is a Load and Right is not; move it right.
81 add->swap_edges(1, 2);
82 return true;
83 }
84
85 PhiNode *phi;
86 // Check for tight loop increments: Loop-phi of Add of loop-phi
87 if( in1->is_Phi() && (phi = in1->as_Phi()) && !phi->is_copy() && phi->region()->is_Loop() && phi->in(2)==add)
88 return false;
89 if( in2->is_Phi() && (phi = in2->as_Phi()) && !phi->is_copy() && phi->region()->is_Loop() && phi->in(2)==add){
90 add->swap_edges(1, 2);
91 return true;
92 }
93
94 // Otherwise, sort inputs (commutativity) to help value numbering.
95 if( in1->_idx > in2->_idx ) {
96 add->swap_edges(1, 2);
97 return true;
98 }
99 return false;
100 }
101
102 //------------------------------Idealize---------------------------------------
103 // If we get here, we assume we are associative!
104 Node *AddNode::Ideal(PhaseGVN *phase, bool can_reshape) {
105 const Type *t1 = phase->type( in(1) );
106 const Type *t2 = phase->type( in(2) );
107 int con_left = t1->singleton();
108 int con_right = t2->singleton();
109
110 // Check for commutative operation desired
111 if( commute(this,con_left,con_right) ) return this;
112
113 AddNode *progress = NULL; // Progress flag
114
115 // Convert "(x+1)+2" into "x+(1+2)". If the right input is a
116 // constant, and the left input is an add of a constant, flatten the
117 // expression tree.
118 Node *add1 = in(1);
119 Node *add2 = in(2);
120 int add1_op = add1->Opcode();
121 int this_op = Opcode();
122 if( con_right && t2 != Type::TOP && // Right input is a constant?
123 add1_op == this_op ) { // Left input is an Add?
124
125 // Type of left _in right input
126 const Type *t12 = phase->type( add1->in(2) );
127 if( t12->singleton() && t12 != Type::TOP ) { // Left input is an add of a constant?
128 // Check for rare case of closed data cycle which can happen inside
129 // unreachable loops. In these cases the computation is undefined.
130 #ifdef ASSERT
131 Node *add11 = add1->in(1);
132 int add11_op = add11->Opcode();
133 if( (add1 == add1->in(1))
134 || (add11_op == this_op && add11->in(1) == add1) ) {
135 assert(false, "dead loop in AddNode::Ideal");
136 }
137 #endif
138 // The Add of the flattened expression
139 Node *x1 = add1->in(1);
140 Node *x2 = phase->makecon( add1->as_Add()->add_ring( t2, t12 ));
141 PhaseIterGVN *igvn = phase->is_IterGVN();
142 if( igvn ) {
143 set_req_X(2,x2,igvn);
144 set_req_X(1,x1,igvn);
145 } else {
146 set_req(2,x2);
147 set_req(1,x1);
148 }
149 progress = this; // Made progress
150 add1 = in(1);
151 add1_op = add1->Opcode();
152 }
153 }
154
155 // Convert "(x+1)+y" into "(x+y)+1". Push constants down the expression tree.
156 if( add1_op == this_op && !con_right ) {
157 Node *a12 = add1->in(2);
158 const Type *t12 = phase->type( a12 );
159 if( t12->singleton() && t12 != Type::TOP && (add1 != add1->in(1)) &&
160 !(add1->in(1)->is_Phi() && add1->in(1)->as_Phi()->is_tripcount()) ) {
161 assert(add1->in(1) != this, "dead loop in AddNode::Ideal");
162 add2 = add1->clone();
163 add2->set_req(2, in(2));
164 add2 = phase->transform(add2);
165 set_req(1, add2);
166 set_req(2, a12);
167 progress = this;
168 add2 = a12;
169 }
170 }
171
172 // Convert "x+(y+1)" into "(x+y)+1". Push constants down the expression tree.
173 int add2_op = add2->Opcode();
174 if( add2_op == this_op && !con_left ) {
175 Node *a22 = add2->in(2);
176 const Type *t22 = phase->type( a22 );
177 if( t22->singleton() && t22 != Type::TOP && (add2 != add2->in(1)) &&
178 !(add2->in(1)->is_Phi() && add2->in(1)->as_Phi()->is_tripcount()) ) {
179 assert(add2->in(1) != this, "dead loop in AddNode::Ideal");
180 Node *addx = add2->clone();
181 addx->set_req(1, in(1));
182 addx->set_req(2, add2->in(1));
183 addx = phase->transform(addx);
184 set_req(1, addx);
185 set_req(2, a22);
186 progress = this;
187 }
188 }
189
190 return progress;
191 }
192
193 //------------------------------Value-----------------------------------------
194 // An add node sums it's two _in. If one input is an RSD, we must mixin
195 // the other input's symbols.
196 const Type *AddNode::Value( PhaseTransform *phase ) const {
197 // Either input is TOP ==> the result is TOP
198 const Type *t1 = phase->type( in(1) );
199 const Type *t2 = phase->type( in(2) );
200 if( t1 == Type::TOP ) return Type::TOP;
201 if( t2 == Type::TOP ) return Type::TOP;
202
203 // Either input is BOTTOM ==> the result is the local BOTTOM
204 const Type *bot = bottom_type();
205 if( (t1 == bot) || (t2 == bot) ||
206 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
207 return bot;
208
209 // Check for an addition involving the additive identity
210 const Type *tadd = add_of_identity( t1, t2 );
211 if( tadd ) return tadd;
212
213 return add_ring(t1,t2); // Local flavor of type addition
214 }
215
216 //------------------------------add_identity-----------------------------------
217 // Check for addition of the identity
218 const Type *AddNode::add_of_identity( const Type *t1, const Type *t2 ) const {
219 const Type *zero = add_id(); // The additive identity
220 if( t1->higher_equal( zero ) ) return t2;
221 if( t2->higher_equal( zero ) ) return t1;
222
223 return NULL;
224 }
225
226
227 //=============================================================================
228 //------------------------------Idealize---------------------------------------
229 Node *AddINode::Ideal(PhaseGVN *phase, bool can_reshape) {
230 Node* in1 = in(1);
231 Node* in2 = in(2);
232 int op1 = in1->Opcode();
233 int op2 = in2->Opcode();
234 // Fold (con1-x)+con2 into (con1+con2)-x
235 if ( op1 == Op_AddI && op2 == Op_SubI ) {
236 // Swap edges to try optimizations below
237 in1 = in2;
238 in2 = in(1);
239 op1 = op2;
240 op2 = in2->Opcode();
241 }
242 if( op1 == Op_SubI ) {
243 const Type *t_sub1 = phase->type( in1->in(1) );
244 const Type *t_2 = phase->type( in2 );
245 if( t_sub1->singleton() && t_2->singleton() && t_sub1 != Type::TOP && t_2 != Type::TOP )
246 return new (phase->C, 3) SubINode(phase->makecon( add_ring( t_sub1, t_2 ) ),
247 in1->in(2) );
248 // Convert "(a-b)+(c-d)" into "(a+c)-(b+d)"
249 if( op2 == Op_SubI ) {
250 // Check for dead cycle: d = (a-b)+(c-d)
251 assert( in1->in(2) != this && in2->in(2) != this,
252 "dead loop in AddINode::Ideal" );
253 Node *sub = new (phase->C, 3) SubINode(NULL, NULL);
254 sub->init_req(1, phase->transform(new (phase->C, 3) AddINode(in1->in(1), in2->in(1) ) ));
255 sub->init_req(2, phase->transform(new (phase->C, 3) AddINode(in1->in(2), in2->in(2) ) ));
256 return sub;
257 }
258 // Convert "(a-b)+(b+c)" into "(a+c)"
259 if( op2 == Op_AddI && in1->in(2) == in2->in(1) ) {
260 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddINode::Ideal");
261 return new (phase->C, 3) AddINode(in1->in(1), in2->in(2));
262 }
263 // Convert "(a-b)+(c+b)" into "(a+c)"
264 if( op2 == Op_AddI && in1->in(2) == in2->in(2) ) {
265 assert(in1->in(1) != this && in2->in(1) != this,"dead loop in AddINode::Ideal");
266 return new (phase->C, 3) AddINode(in1->in(1), in2->in(1));
267 }
268 // Convert "(a-b)+(b-c)" into "(a-c)"
269 if( op2 == Op_SubI && in1->in(2) == in2->in(1) ) {
270 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddINode::Ideal");
271 return new (phase->C, 3) SubINode(in1->in(1), in2->in(2));
272 }
273 // Convert "(a-b)+(c-a)" into "(c-b)"
274 if( op2 == Op_SubI && in1->in(1) == in2->in(2) ) {
275 assert(in1->in(2) != this && in2->in(1) != this,"dead loop in AddINode::Ideal");
276 return new (phase->C, 3) SubINode(in2->in(1), in1->in(2));
277 }
278 }
279
280 // Convert "x+(0-y)" into "(x-y)"
281 if( op2 == Op_SubI && phase->type(in2->in(1)) == TypeInt::ZERO )
282 return new (phase->C, 3) SubINode(in1, in2->in(2) );
283
284 // Convert "(0-y)+x" into "(x-y)"
285 if( op1 == Op_SubI && phase->type(in1->in(1)) == TypeInt::ZERO )
286 return new (phase->C, 3) SubINode( in2, in1->in(2) );
287
288 // Convert (x>>>z)+y into (x+(y<<z))>>>z for small constant z and y.
289 // Helps with array allocation math constant folding
290 // See 4790063:
291 // Unrestricted transformation is unsafe for some runtime values of 'x'
292 // ( x == 0, z == 1, y == -1 ) fails
293 // ( x == -5, z == 1, y == 1 ) fails
294 // Transform works for small z and small negative y when the addition
295 // (x + (y << z)) does not cross zero.
296 // Implement support for negative y and (x >= -(y << z))
297 // Have not observed cases where type information exists to support
298 // positive y and (x <= -(y << z))
299 if( op1 == Op_URShiftI && op2 == Op_ConI &&
300 in1->in(2)->Opcode() == Op_ConI ) {
301 jint z = phase->type( in1->in(2) )->is_int()->get_con() & 0x1f; // only least significant 5 bits matter
302 jint y = phase->type( in2 )->is_int()->get_con();
303
304 if( z < 5 && -5 < y && y < 0 ) {
305 const Type *t_in11 = phase->type(in1->in(1));
306 if( t_in11 != Type::TOP && (t_in11->is_int()->_lo >= -(y << z)) ) {
307 Node *a = phase->transform( new (phase->C, 3) AddINode( in1->in(1), phase->intcon(y<<z) ) );
308 return new (phase->C, 3) URShiftINode( a, in1->in(2) );
309 }
310 }
311 }
312
313 return AddNode::Ideal(phase, can_reshape);
314 }
315
316
317 //------------------------------Identity---------------------------------------
318 // Fold (x-y)+y OR y+(x-y) into x
319 Node *AddINode::Identity( PhaseTransform *phase ) {
320 if( in(1)->Opcode() == Op_SubI && phase->eqv(in(1)->in(2),in(2)) ) {
321 return in(1)->in(1);
322 }
323 else if( in(2)->Opcode() == Op_SubI && phase->eqv(in(2)->in(2),in(1)) ) {
324 return in(2)->in(1);
325 }
326 return AddNode::Identity(phase);
327 }
328
329
330 //------------------------------add_ring---------------------------------------
331 // Supplied function returns the sum of the inputs. Guaranteed never
332 // to be passed a TOP or BOTTOM type, these are filtered out by
333 // pre-check.
334 const Type *AddINode::add_ring( const Type *t0, const Type *t1 ) const {
335 const TypeInt *r0 = t0->is_int(); // Handy access
336 const TypeInt *r1 = t1->is_int();
337 int lo = r0->_lo + r1->_lo;
338 int hi = r0->_hi + r1->_hi;
339 if( !(r0->is_con() && r1->is_con()) ) {
340 // Not both constants, compute approximate result
341 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
342 lo = min_jint; hi = max_jint; // Underflow on the low side
343 }
344 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
345 lo = min_jint; hi = max_jint; // Overflow on the high side
346 }
347 if( lo > hi ) { // Handle overflow
348 lo = min_jint; hi = max_jint;
349 }
350 } else {
351 // both constants, compute precise result using 'lo' and 'hi'
352 // Semantics define overflow and underflow for integer addition
353 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
354 }
355 return TypeInt::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
356 }
357
358
359 //=============================================================================
360 //------------------------------Idealize---------------------------------------
361 Node *AddLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
362 Node* in1 = in(1);
363 Node* in2 = in(2);
364 int op1 = in1->Opcode();
365 int op2 = in2->Opcode();
366 // Fold (con1-x)+con2 into (con1+con2)-x
367 if ( op1 == Op_AddL && op2 == Op_SubL ) {
368 // Swap edges to try optimizations below
369 in1 = in2;
370 in2 = in(1);
371 op1 = op2;
372 op2 = in2->Opcode();
373 }
374 // Fold (con1-x)+con2 into (con1+con2)-x
375 if( op1 == Op_SubL ) {
376 const Type *t_sub1 = phase->type( in1->in(1) );
377 const Type *t_2 = phase->type( in2 );
378 if( t_sub1->singleton() && t_2->singleton() && t_sub1 != Type::TOP && t_2 != Type::TOP )
379 return new (phase->C, 3) SubLNode(phase->makecon( add_ring( t_sub1, t_2 ) ),
380 in1->in(2) );
381 // Convert "(a-b)+(c-d)" into "(a+c)-(b+d)"
382 if( op2 == Op_SubL ) {
383 // Check for dead cycle: d = (a-b)+(c-d)
384 assert( in1->in(2) != this && in2->in(2) != this,
385 "dead loop in AddLNode::Ideal" );
386 Node *sub = new (phase->C, 3) SubLNode(NULL, NULL);
387 sub->init_req(1, phase->transform(new (phase->C, 3) AddLNode(in1->in(1), in2->in(1) ) ));
388 sub->init_req(2, phase->transform(new (phase->C, 3) AddLNode(in1->in(2), in2->in(2) ) ));
389 return sub;
390 }
391 // Convert "(a-b)+(b+c)" into "(a+c)"
392 if( op2 == Op_AddL && in1->in(2) == in2->in(1) ) {
393 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddLNode::Ideal");
394 return new (phase->C, 3) AddLNode(in1->in(1), in2->in(2));
395 }
396 // Convert "(a-b)+(c+b)" into "(a+c)"
397 if( op2 == Op_AddL && in1->in(2) == in2->in(2) ) {
398 assert(in1->in(1) != this && in2->in(1) != this,"dead loop in AddLNode::Ideal");
399 return new (phase->C, 3) AddLNode(in1->in(1), in2->in(1));
400 }
401 // Convert "(a-b)+(b-c)" into "(a-c)"
402 if( op2 == Op_SubL && in1->in(2) == in2->in(1) ) {
403 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddLNode::Ideal");
404 return new (phase->C, 3) SubLNode(in1->in(1), in2->in(2));
405 }
406 // Convert "(a-b)+(c-a)" into "(c-b)"
407 if( op2 == Op_SubL && in1->in(1) == in1->in(2) ) {
408 assert(in1->in(2) != this && in2->in(1) != this,"dead loop in AddLNode::Ideal");
409 return new (phase->C, 3) SubLNode(in2->in(1), in1->in(2));
410 }
411 }
412
413 // Convert "x+(0-y)" into "(x-y)"
414 if( op2 == Op_SubL && phase->type(in2->in(1)) == TypeLong::ZERO )
415 return new (phase->C, 3) SubLNode( in1, in2->in(2) );
416
417 // Convert "(0-y)+x" into "(x-y)"
418 if( op1 == Op_SubL && phase->type(in1->in(1)) == TypeInt::ZERO )
419 return new (phase->C, 3) SubLNode( in2, in1->in(2) );
420
421 // Convert "X+X+X+X+X...+X+Y" into "k*X+Y" or really convert "X+(X+Y)"
422 // into "(X<<1)+Y" and let shift-folding happen.
423 if( op2 == Op_AddL &&
424 in2->in(1) == in1 &&
425 op1 != Op_ConL &&
426 0 ) {
427 Node *shift = phase->transform(new (phase->C, 3) LShiftLNode(in1,phase->intcon(1)));
428 return new (phase->C, 3) AddLNode(shift,in2->in(2));
429 }
430
431 return AddNode::Ideal(phase, can_reshape);
432 }
433
434
435 //------------------------------Identity---------------------------------------
436 // Fold (x-y)+y OR y+(x-y) into x
437 Node *AddLNode::Identity( PhaseTransform *phase ) {
438 if( in(1)->Opcode() == Op_SubL && phase->eqv(in(1)->in(2),in(2)) ) {
439 return in(1)->in(1);
440 }
441 else if( in(2)->Opcode() == Op_SubL && phase->eqv(in(2)->in(2),in(1)) ) {
442 return in(2)->in(1);
443 }
444 return AddNode::Identity(phase);
445 }
446
447
448 //------------------------------add_ring---------------------------------------
449 // Supplied function returns the sum of the inputs. Guaranteed never
450 // to be passed a TOP or BOTTOM type, these are filtered out by
451 // pre-check.
452 const Type *AddLNode::add_ring( const Type *t0, const Type *t1 ) const {
453 const TypeLong *r0 = t0->is_long(); // Handy access
454 const TypeLong *r1 = t1->is_long();
455 jlong lo = r0->_lo + r1->_lo;
456 jlong hi = r0->_hi + r1->_hi;
457 if( !(r0->is_con() && r1->is_con()) ) {
458 // Not both constants, compute approximate result
459 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
460 lo =min_jlong; hi = max_jlong; // Underflow on the low side
461 }
462 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
463 lo = min_jlong; hi = max_jlong; // Overflow on the high side
464 }
465 if( lo > hi ) { // Handle overflow
466 lo = min_jlong; hi = max_jlong;
467 }
468 } else {
469 // both constants, compute precise result using 'lo' and 'hi'
470 // Semantics define overflow and underflow for integer addition
471 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
472 }
473 return TypeLong::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
474 }
475
476
477 //=============================================================================
478 //------------------------------add_of_identity--------------------------------
479 // Check for addition of the identity
480 const Type *AddFNode::add_of_identity( const Type *t1, const Type *t2 ) const {
481 // x ADD 0 should return x unless 'x' is a -zero
482 //
483 // const Type *zero = add_id(); // The additive identity
484 // jfloat f1 = t1->getf();
485 // jfloat f2 = t2->getf();
486 //
487 // if( t1->higher_equal( zero ) ) return t2;
488 // if( t2->higher_equal( zero ) ) return t1;
489
490 return NULL;
491 }
492
493 //------------------------------add_ring---------------------------------------
494 // Supplied function returns the sum of the inputs.
495 // This also type-checks the inputs for sanity. Guaranteed never to
496 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
497 const Type *AddFNode::add_ring( const Type *t0, const Type *t1 ) const {
498 // We must be adding 2 float constants.
499 return TypeF::make( t0->getf() + t1->getf() );
500 }
501
502 //------------------------------Ideal------------------------------------------
503 Node *AddFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
504 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
505 return AddNode::Ideal(phase, can_reshape); // commutative and associative transforms
506 }
507
508 // Floating point additions are not associative because of boundary conditions (infinity)
509 return commute(this,
510 phase->type( in(1) )->singleton(),
511 phase->type( in(2) )->singleton() ) ? this : NULL;
512 }
513
514
515 //=============================================================================
516 //------------------------------add_of_identity--------------------------------
517 // Check for addition of the identity
518 const Type *AddDNode::add_of_identity( const Type *t1, const Type *t2 ) const {
519 // x ADD 0 should return x unless 'x' is a -zero
520 //
521 // const Type *zero = add_id(); // The additive identity
522 // jfloat f1 = t1->getf();
523 // jfloat f2 = t2->getf();
524 //
525 // if( t1->higher_equal( zero ) ) return t2;
526 // if( t2->higher_equal( zero ) ) return t1;
527
528 return NULL;
529 }
530 //------------------------------add_ring---------------------------------------
531 // Supplied function returns the sum of the inputs.
532 // This also type-checks the inputs for sanity. Guaranteed never to
533 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
534 const Type *AddDNode::add_ring( const Type *t0, const Type *t1 ) const {
535 // We must be adding 2 double constants.
536 return TypeD::make( t0->getd() + t1->getd() );
537 }
538
539 //------------------------------Ideal------------------------------------------
540 Node *AddDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
541 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
542 return AddNode::Ideal(phase, can_reshape); // commutative and associative transforms
543 }
544
545 // Floating point additions are not associative because of boundary conditions (infinity)
546 return commute(this,
547 phase->type( in(1) )->singleton(),
548 phase->type( in(2) )->singleton() ) ? this : NULL;
549 }
550
551
552 //=============================================================================
553 //------------------------------Identity---------------------------------------
554 // If one input is a constant 0, return the other input.
555 Node *AddPNode::Identity( PhaseTransform *phase ) {
556 return ( phase->type( in(Offset) )->higher_equal( TypeX_ZERO ) ) ? in(Address) : this;
557 }
558
559 //------------------------------Idealize---------------------------------------
560 Node *AddPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
561 // Bail out if dead inputs
562 if( phase->type( in(Address) ) == Type::TOP ) return NULL;
563
564 // If the left input is an add of a constant, flatten the expression tree.
565 const Node *n = in(Address);
566 if (n->is_AddP() && n->in(Base) == in(Base)) {
567 const AddPNode *addp = n->as_AddP(); // Left input is an AddP
568 assert( !addp->in(Address)->is_AddP() ||
569 addp->in(Address)->as_AddP() != addp,
570 "dead loop in AddPNode::Ideal" );
571 // Type of left input's right input
572 const Type *t = phase->type( addp->in(Offset) );
573 if( t == Type::TOP ) return NULL;
574 const TypeX *t12 = t->is_intptr_t();
575 if( t12->is_con() ) { // Left input is an add of a constant?
576 // If the right input is a constant, combine constants
577 const Type *temp_t2 = phase->type( in(Offset) );
578 if( temp_t2 == Type::TOP ) return NULL;
579 const TypeX *t2 = temp_t2->is_intptr_t();
580 Node* address;
581 Node* offset;
582 if( t2->is_con() ) {
583 // The Add of the flattened expression
584 address = addp->in(Address);
585 offset = phase->MakeConX(t2->get_con() + t12->get_con());
586 } else {
587 // Else move the constant to the right. ((A+con)+B) into ((A+B)+con)
588 address = phase->transform(new (phase->C, 4) AddPNode(in(Base),addp->in(Address),in(Offset)));
589 offset = addp->in(Offset);
590 }
591 PhaseIterGVN *igvn = phase->is_IterGVN();
592 if( igvn ) {
593 set_req_X(Address,address,igvn);
594 set_req_X(Offset,offset,igvn);
595 } else {
596 set_req(Address,address);
597 set_req(Offset,offset);
598 }
599 return this;
600 }
601 }
602
603 // Raw pointers?
604 if( in(Base)->bottom_type() == Type::TOP ) {
605 // If this is a NULL+long form (from unsafe accesses), switch to a rawptr.
606 if (phase->type(in(Address)) == TypePtr::NULL_PTR) {
607 Node* offset = in(Offset);
608 return new (phase->C, 2) CastX2PNode(offset);
609 }
610 }
611
612 // If the right is an add of a constant, push the offset down.
613 // Convert: (ptr + (offset+con)) into (ptr+offset)+con.
614 // The idea is to merge array_base+scaled_index groups together,
615 // and only have different constant offsets from the same base.
616 const Node *add = in(Offset);
617 if( add->Opcode() == Op_AddX && add->in(1) != add ) {
618 const Type *t22 = phase->type( add->in(2) );
619 if( t22->singleton() && (t22 != Type::TOP) ) { // Right input is an add of a constant?
620 set_req(Address, phase->transform(new (phase->C, 4) AddPNode(in(Base),in(Address),add->in(1))));
621 set_req(Offset, add->in(2));
622 return this; // Made progress
623 }
624 }
625
626 return NULL; // No progress
627 }
628
629 //------------------------------bottom_type------------------------------------
630 // Bottom-type is the pointer-type with unknown offset.
631 const Type *AddPNode::bottom_type() const {
632 if (in(Address) == NULL) return TypePtr::BOTTOM;
633 const TypePtr *tp = in(Address)->bottom_type()->isa_ptr();
634 if( !tp ) return Type::TOP; // TOP input means TOP output
635 assert( in(Offset)->Opcode() != Op_ConP, "" );
636 const Type *t = in(Offset)->bottom_type();
637 if( t == Type::TOP )
638 return tp->add_offset(Type::OffsetTop);
639 const TypeX *tx = t->is_intptr_t();
640 intptr_t txoffset = Type::OffsetBot;
641 if (tx->is_con()) { // Left input is an add of a constant?
642 txoffset = tx->get_con();
643 }
644 return tp->add_offset(txoffset);
645 }
646
647 //------------------------------Value------------------------------------------
648 const Type *AddPNode::Value( PhaseTransform *phase ) const {
649 // Either input is TOP ==> the result is TOP
650 const Type *t1 = phase->type( in(Address) );
651 const Type *t2 = phase->type( in(Offset) );
652 if( t1 == Type::TOP ) return Type::TOP;
653 if( t2 == Type::TOP ) return Type::TOP;
654
655 // Left input is a pointer
656 const TypePtr *p1 = t1->isa_ptr();
657 // Right input is an int
658 const TypeX *p2 = t2->is_intptr_t();
659 // Add 'em
660 intptr_t p2offset = Type::OffsetBot;
661 if (p2->is_con()) { // Left input is an add of a constant?
662 p2offset = p2->get_con();
663 }
664 return p1->add_offset(p2offset);
665 }
666
667 //------------------------Ideal_base_and_offset--------------------------------
668 // Split an oop pointer into a base and offset.
669 // (The offset might be Type::OffsetBot in the case of an array.)
670 // Return the base, or NULL if failure.
671 Node* AddPNode::Ideal_base_and_offset(Node* ptr, PhaseTransform* phase,
672 // second return value:
673 intptr_t& offset) {
674 if (ptr->is_AddP()) {
675 Node* base = ptr->in(AddPNode::Base);
676 Node* addr = ptr->in(AddPNode::Address);
677 Node* offs = ptr->in(AddPNode::Offset);
678 if (base == addr || base->is_top()) {
679 offset = phase->find_intptr_t_con(offs, Type::OffsetBot);
680 if (offset != Type::OffsetBot) {
681 return addr;
682 }
683 }
684 }
685 offset = Type::OffsetBot;
686 return NULL;
687 }
688
689 //------------------------------unpack_offsets----------------------------------
690 // Collect the AddP offset values into the elements array, giving up
691 // if there are more than length.
692 int AddPNode::unpack_offsets(Node* elements[], int length) {
693 int count = 0;
694 Node* addr = this;
695 Node* base = addr->in(AddPNode::Base);
696 while (addr->is_AddP()) {
697 if (addr->in(AddPNode::Base) != base) {
698 // give up
699 return -1;
700 }
701 elements[count++] = addr->in(AddPNode::Offset);
702 if (count == length) {
703 // give up
704 return -1;
705 }
706 addr = addr->in(AddPNode::Address);
707 }
708 if (addr != base) {
709 return -1;
710 }
711 return count;
712 }
713
714 //------------------------------match_edge-------------------------------------
715 // Do we Match on this edge index or not? Do not match base pointer edge
716 uint AddPNode::match_edge(uint idx) const {
717 return idx > Base;
718 }
719
720 //=============================================================================
721 //------------------------------Identity---------------------------------------
722 Node *OrINode::Identity( PhaseTransform *phase ) {
723 // x | x => x
724 if (phase->eqv(in(1), in(2))) {
725 return in(1);
726 }
727
728 return AddNode::Identity(phase);
729 }
730
731 //------------------------------add_ring---------------------------------------
732 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
733 // the logical operations the ring's ADD is really a logical OR function.
734 // This also type-checks the inputs for sanity. Guaranteed never to
735 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
736 const Type *OrINode::add_ring( const Type *t0, const Type *t1 ) const {
737 const TypeInt *r0 = t0->is_int(); // Handy access
738 const TypeInt *r1 = t1->is_int();
739
740 // If both args are bool, can figure out better types
741 if ( r0 == TypeInt::BOOL ) {
742 if ( r1 == TypeInt::ONE) {
743 return TypeInt::ONE;
744 } else if ( r1 == TypeInt::BOOL ) {
745 return TypeInt::BOOL;
746 }
747 } else if ( r0 == TypeInt::ONE ) {
748 if ( r1 == TypeInt::BOOL ) {
749 return TypeInt::ONE;
750 }
751 }
752
753 // If either input is not a constant, just return all integers.
754 if( !r0->is_con() || !r1->is_con() )
755 return TypeInt::INT; // Any integer, but still no symbols.
756
757 // Otherwise just OR them bits.
758 return TypeInt::make( r0->get_con() | r1->get_con() );
759 }
760
761 //=============================================================================
762 //------------------------------Identity---------------------------------------
763 Node *OrLNode::Identity( PhaseTransform *phase ) {
764 // x | x => x
765 if (phase->eqv(in(1), in(2))) {
766 return in(1);
767 }
768
769 return AddNode::Identity(phase);
770 }
771
772 //------------------------------add_ring---------------------------------------
773 const Type *OrLNode::add_ring( const Type *t0, const Type *t1 ) const {
774 const TypeLong *r0 = t0->is_long(); // Handy access
775 const TypeLong *r1 = t1->is_long();
776
777 // If either input is not a constant, just return all integers.
778 if( !r0->is_con() || !r1->is_con() )
779 return TypeLong::LONG; // Any integer, but still no symbols.
780
781 // Otherwise just OR them bits.
782 return TypeLong::make( r0->get_con() | r1->get_con() );
783 }
784
785 //=============================================================================
786 //------------------------------add_ring---------------------------------------
787 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
788 // the logical operations the ring's ADD is really a logical OR function.
789 // This also type-checks the inputs for sanity. Guaranteed never to
790 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
791 const Type *XorINode::add_ring( const Type *t0, const Type *t1 ) const {
792 const TypeInt *r0 = t0->is_int(); // Handy access
793 const TypeInt *r1 = t1->is_int();
794
795 // Complementing a boolean?
796 if( r0 == TypeInt::BOOL && ( r1 == TypeInt::ONE
797 || r1 == TypeInt::BOOL))
798 return TypeInt::BOOL;
799
800 if( !r0->is_con() || !r1->is_con() ) // Not constants
801 return TypeInt::INT; // Any integer, but still no symbols.
802
803 // Otherwise just XOR them bits.
804 return TypeInt::make( r0->get_con() ^ r1->get_con() );
805 }
806
807 //=============================================================================
808 //------------------------------add_ring---------------------------------------
809 const Type *XorLNode::add_ring( const Type *t0, const Type *t1 ) const {
810 const TypeLong *r0 = t0->is_long(); // Handy access
811 const TypeLong *r1 = t1->is_long();
812
813 // If either input is not a constant, just return all integers.
814 if( !r0->is_con() || !r1->is_con() )
815 return TypeLong::LONG; // Any integer, but still no symbols.
816
817 // Otherwise just OR them bits.
818 return TypeLong::make( r0->get_con() ^ r1->get_con() );
819 }
820
821 //=============================================================================
822 //------------------------------add_ring---------------------------------------
823 // Supplied function returns the sum of the inputs.
824 const Type *MaxINode::add_ring( const Type *t0, const Type *t1 ) const {
825 const TypeInt *r0 = t0->is_int(); // Handy access
826 const TypeInt *r1 = t1->is_int();
827
828 // Otherwise just MAX them bits.
829 return TypeInt::make( MAX2(r0->_lo,r1->_lo), MAX2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
830 }
831
832 //=============================================================================
833 //------------------------------Idealize---------------------------------------
834 // MINs show up in range-check loop limit calculations. Look for
835 // "MIN2(x+c0,MIN2(y,x+c1))". Pick the smaller constant: "MIN2(x+c0,y)"
836 Node *MinINode::Ideal(PhaseGVN *phase, bool can_reshape) {
837 Node *progress = NULL;
838 // Force a right-spline graph
839 Node *l = in(1);
840 Node *r = in(2);
841 // Transform MinI1( MinI2(a,b), c) into MinI1( a, MinI2(b,c) )
842 // to force a right-spline graph for the rest of MinINode::Ideal().
843 if( l->Opcode() == Op_MinI ) {
844 assert( l != l->in(1), "dead loop in MinINode::Ideal" );
845 r = phase->transform(new (phase->C, 3) MinINode(l->in(2),r));
846 l = l->in(1);
847 set_req(1, l);
848 set_req(2, r);
849 return this;
850 }
851
852 // Get left input & constant
853 Node *x = l;
854 int x_off = 0;
855 if( x->Opcode() == Op_AddI && // Check for "x+c0" and collect constant
856 x->in(2)->is_Con() ) {
857 const Type *t = x->in(2)->bottom_type();
858 if( t == Type::TOP ) return NULL; // No progress
859 x_off = t->is_int()->get_con();
860 x = x->in(1);
861 }
862
863 // Scan a right-spline-tree for MINs
864 Node *y = r;
865 int y_off = 0;
866 // Check final part of MIN tree
867 if( y->Opcode() == Op_AddI && // Check for "y+c1" and collect constant
868 y->in(2)->is_Con() ) {
869 const Type *t = y->in(2)->bottom_type();
870 if( t == Type::TOP ) return NULL; // No progress
871 y_off = t->is_int()->get_con();
872 y = y->in(1);
873 }
874 if( x->_idx > y->_idx && r->Opcode() != Op_MinI ) {
875 swap_edges(1, 2);
876 return this;
877 }
878
879
880 if( r->Opcode() == Op_MinI ) {
881 assert( r != r->in(2), "dead loop in MinINode::Ideal" );
882 y = r->in(1);
883 // Check final part of MIN tree
884 if( y->Opcode() == Op_AddI &&// Check for "y+c1" and collect constant
885 y->in(2)->is_Con() ) {
886 const Type *t = y->in(2)->bottom_type();
887 if( t == Type::TOP ) return NULL; // No progress
888 y_off = t->is_int()->get_con();
889 y = y->in(1);
890 }
891
892 if( x->_idx > y->_idx )
893 return new (phase->C, 3) MinINode(r->in(1),phase->transform(new (phase->C, 3) MinINode(l,r->in(2))));
894
895 // See if covers: MIN2(x+c0,MIN2(y+c1,z))
896 if( !phase->eqv(x,y) ) return NULL;
897 // If (y == x) transform MIN2(x+c0, MIN2(x+c1,z)) into
898 // MIN2(x+c0 or x+c1 which less, z).
899 return new (phase->C, 3) MinINode(phase->transform(new (phase->C, 3) AddINode(x,phase->intcon(MIN2(x_off,y_off)))),r->in(2));
900 } else {
901 // See if covers: MIN2(x+c0,y+c1)
902 if( !phase->eqv(x,y) ) return NULL;
903 // If (y == x) transform MIN2(x+c0,x+c1) into x+c0 or x+c1 which less.
904 return new (phase->C, 3) AddINode(x,phase->intcon(MIN2(x_off,y_off)));
905 }
906
907 }
908
909 //------------------------------add_ring---------------------------------------
910 // Supplied function returns the sum of the inputs.
911 const Type *MinINode::add_ring( const Type *t0, const Type *t1 ) const {
912 const TypeInt *r0 = t0->is_int(); // Handy access
913 const TypeInt *r1 = t1->is_int();
914
915 // Otherwise just MIN them bits.
916 return TypeInt::make( MIN2(r0->_lo,r1->_lo), MIN2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
917 }