1 /*
2 * Copyright (c) 1997, 2012, 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 #include "precompiled.hpp"
26 #include "memory/allocation.inline.hpp"
27 #include "opto/addnode.hpp"
28 #include "opto/cfgnode.hpp"
29 #include "opto/connode.hpp"
30 #include "opto/machnode.hpp"
31 #include "opto/mulnode.hpp"
32 #include "opto/phaseX.hpp"
33 #include "opto/subnode.hpp"
34
35 // Portions of code courtesy of Clifford Click
36
37 // Classic Add functionality. This covers all the usual 'add' behaviors for
38 // an algebraic ring. Add-integer, add-float, add-double, and binary-or are
39 // all inherited from this class. The various identity values are supplied
40 // by virtual functions.
41
42
43 //=============================================================================
44 //------------------------------hash-------------------------------------------
45 // Hash function over AddNodes. Needs to be commutative; i.e., I swap
46 // (commute) inputs to AddNodes willy-nilly so the hash function must return
47 // the same value in the presence of edge swapping.
48 uint AddNode::hash() const {
49 return (uintptr_t)in(1) + (uintptr_t)in(2) + Opcode();
50 }
51
52 //------------------------------Identity---------------------------------------
53 // If either input is a constant 0, return the other input.
54 Node *AddNode::Identity( PhaseTransform *phase ) {
55 const Type *zero = add_id(); // The additive identity
56 if( phase->type( in(1) )->higher_equal( zero ) ) return in(2);
57 if( phase->type( in(2) )->higher_equal( zero ) ) return in(1);
58 return this;
59 }
60
61 //------------------------------commute----------------------------------------
62 // Commute operands to move loads and constants to the right.
63 static bool commute( Node *add, int con_left, int con_right ) {
64 Node *in1 = add->in(1);
65 Node *in2 = add->in(2);
66
67 // Convert "1+x" into "x+1".
68 // Right is a constant; leave it
69 if( con_right ) return false;
70 // Left is a constant; move it right.
71 if( con_left ) {
72 add->swap_edges(1, 2);
73 return true;
74 }
75
76 // Convert "Load+x" into "x+Load".
77 // Now check for loads
78 if (in2->is_Load()) {
79 if (!in1->is_Load()) {
80 // already x+Load to return
81 return false;
82 }
83 // both are loads, so fall through to sort inputs by idx
84 } else if( in1->is_Load() ) {
85 // Left is a Load and Right is not; move it right.
86 add->swap_edges(1, 2);
87 return true;
88 }
89
90 PhiNode *phi;
91 // Check for tight loop increments: Loop-phi of Add of loop-phi
92 if( in1->is_Phi() && (phi = in1->as_Phi()) && !phi->is_copy() && phi->region()->is_Loop() && phi->in(2)==add)
93 return false;
94 if( in2->is_Phi() && (phi = in2->as_Phi()) && !phi->is_copy() && phi->region()->is_Loop() && phi->in(2)==add){
95 add->swap_edges(1, 2);
96 return true;
97 }
98
99 // Otherwise, sort inputs (commutativity) to help value numbering.
100 if( in1->_idx > in2->_idx ) {
101 add->swap_edges(1, 2);
102 return true;
103 }
104 return false;
105 }
106
107 //------------------------------Idealize---------------------------------------
108 // If we get here, we assume we are associative!
109 Node *AddNode::Ideal(PhaseGVN *phase, bool can_reshape) {
110 const Type *t1 = phase->type( in(1) );
111 const Type *t2 = phase->type( in(2) );
112 int con_left = t1->singleton();
113 int con_right = t2->singleton();
114
115 // Check for commutative operation desired
116 if( commute(this,con_left,con_right) ) return this;
117
118 AddNode *progress = NULL; // Progress flag
119
120 // Convert "(x+1)+2" into "x+(1+2)". If the right input is a
121 // constant, and the left input is an add of a constant, flatten the
122 // expression tree.
123 Node *add1 = in(1);
124 Node *add2 = in(2);
125 int add1_op = add1->Opcode();
126 int this_op = Opcode();
127 if( con_right && t2 != Type::TOP && // Right input is a constant?
128 add1_op == this_op ) { // Left input is an Add?
129
130 // Type of left _in right input
131 const Type *t12 = phase->type( add1->in(2) );
132 if( t12->singleton() && t12 != Type::TOP ) { // Left input is an add of a constant?
133 // Check for rare case of closed data cycle which can happen inside
134 // unreachable loops. In these cases the computation is undefined.
135 #ifdef ASSERT
136 Node *add11 = add1->in(1);
137 int add11_op = add11->Opcode();
138 if( (add1 == add1->in(1))
139 || (add11_op == this_op && add11->in(1) == add1) ) {
140 assert(false, "dead loop in AddNode::Ideal");
141 }
142 #endif
143 // The Add of the flattened expression
144 Node *x1 = add1->in(1);
145 Node *x2 = phase->makecon( add1->as_Add()->add_ring( t2, t12 ));
146 PhaseIterGVN *igvn = phase->is_IterGVN();
147 if( igvn ) {
148 set_req_X(2,x2,igvn);
149 set_req_X(1,x1,igvn);
150 } else {
151 set_req(2,x2);
152 set_req(1,x1);
153 }
154 progress = this; // Made progress
155 add1 = in(1);
156 add1_op = add1->Opcode();
157 }
158 }
159
160 // Convert "(x+1)+y" into "(x+y)+1". Push constants down the expression tree.
161 if( add1_op == this_op && !con_right ) {
162 Node *a12 = add1->in(2);
163 const Type *t12 = phase->type( a12 );
164 if( t12->singleton() && t12 != Type::TOP && (add1 != add1->in(1)) &&
165 !(add1->in(1)->is_Phi() && add1->in(1)->as_Phi()->is_tripcount()) ) {
166 assert(add1->in(1) != this, "dead loop in AddNode::Ideal");
167 add2 = add1->clone();
168 add2->set_req(2, in(2));
169 add2 = phase->transform(add2);
170 set_req(1, add2);
171 set_req(2, a12);
172 progress = this;
173 add2 = a12;
174 }
175 }
176
177 // Convert "x+(y+1)" into "(x+y)+1". Push constants down the expression tree.
178 int add2_op = add2->Opcode();
179 if( add2_op == this_op && !con_left ) {
180 Node *a22 = add2->in(2);
181 const Type *t22 = phase->type( a22 );
182 if( t22->singleton() && t22 != Type::TOP && (add2 != add2->in(1)) &&
183 !(add2->in(1)->is_Phi() && add2->in(1)->as_Phi()->is_tripcount()) ) {
184 assert(add2->in(1) != this, "dead loop in AddNode::Ideal");
185 Node *addx = add2->clone();
186 addx->set_req(1, in(1));
187 addx->set_req(2, add2->in(1));
188 addx = phase->transform(addx);
189 set_req(1, addx);
190 set_req(2, a22);
191 progress = this;
192 }
193 }
194
195 return progress;
196 }
197
198 //------------------------------Value-----------------------------------------
199 // An add node sums it's two _in. If one input is an RSD, we must mixin
200 // the other input's symbols.
201 const Type *AddNode::Value( PhaseTransform *phase ) const {
202 // Either input is TOP ==> the result is TOP
203 const Type *t1 = phase->type( in(1) );
204 const Type *t2 = phase->type( in(2) );
205 if( t1 == Type::TOP ) return Type::TOP;
206 if( t2 == Type::TOP ) return Type::TOP;
207
208 // Either input is BOTTOM ==> the result is the local BOTTOM
209 const Type *bot = bottom_type();
210 if( (t1 == bot) || (t2 == bot) ||
211 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
212 return bot;
213
214 // Check for an addition involving the additive identity
215 const Type *tadd = add_of_identity( t1, t2 );
216 if( tadd ) return tadd;
217
218 return add_ring(t1,t2); // Local flavor of type addition
219 }
220
221 //------------------------------add_identity-----------------------------------
222 // Check for addition of the identity
223 const Type *AddNode::add_of_identity( const Type *t1, const Type *t2 ) const {
224 const Type *zero = add_id(); // The additive identity
225 if( t1->higher_equal( zero ) ) return t2;
226 if( t2->higher_equal( zero ) ) return t1;
227
228 return NULL;
229 }
230
231
232 //=============================================================================
233 //------------------------------Idealize---------------------------------------
234 Node *AddINode::Ideal(PhaseGVN *phase, bool can_reshape) {
235 Node* in1 = in(1);
236 Node* in2 = in(2);
237 int op1 = in1->Opcode();
238 int op2 = in2->Opcode();
239 // Fold (con1-x)+con2 into (con1+con2)-x
240 if ( op1 == Op_AddI && op2 == Op_SubI ) {
241 // Swap edges to try optimizations below
242 in1 = in2;
243 in2 = in(1);
244 op1 = op2;
245 op2 = in2->Opcode();
246 }
247 if( op1 == Op_SubI ) {
248 const Type *t_sub1 = phase->type( in1->in(1) );
249 const Type *t_2 = phase->type( in2 );
250 if( t_sub1->singleton() && t_2->singleton() && t_sub1 != Type::TOP && t_2 != Type::TOP )
251 return new (phase->C) SubINode(phase->makecon( add_ring( t_sub1, t_2 ) ),
252 in1->in(2) );
253 // Convert "(a-b)+(c-d)" into "(a+c)-(b+d)"
254 if( op2 == Op_SubI ) {
255 // Check for dead cycle: d = (a-b)+(c-d)
256 assert( in1->in(2) != this && in2->in(2) != this,
257 "dead loop in AddINode::Ideal" );
258 Node *sub = new (phase->C) SubINode(NULL, NULL);
259 sub->init_req(1, phase->transform(new (phase->C) AddINode(in1->in(1), in2->in(1) ) ));
260 sub->init_req(2, phase->transform(new (phase->C) AddINode(in1->in(2), in2->in(2) ) ));
261 return sub;
262 }
263 // Convert "(a-b)+(b+c)" into "(a+c)"
264 if( op2 == Op_AddI && in1->in(2) == in2->in(1) ) {
265 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddINode::Ideal");
266 return new (phase->C) AddINode(in1->in(1), in2->in(2));
267 }
268 // Convert "(a-b)+(c+b)" into "(a+c)"
269 if( op2 == Op_AddI && in1->in(2) == in2->in(2) ) {
270 assert(in1->in(1) != this && in2->in(1) != this,"dead loop in AddINode::Ideal");
271 return new (phase->C) AddINode(in1->in(1), in2->in(1));
272 }
273 // Convert "(a-b)+(b-c)" into "(a-c)"
274 if( op2 == Op_SubI && in1->in(2) == in2->in(1) ) {
275 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddINode::Ideal");
276 return new (phase->C) SubINode(in1->in(1), in2->in(2));
277 }
278 // Convert "(a-b)+(c-a)" into "(c-b)"
279 if( op2 == Op_SubI && in1->in(1) == in2->in(2) ) {
280 assert(in1->in(2) != this && in2->in(1) != this,"dead loop in AddINode::Ideal");
281 return new (phase->C) SubINode(in2->in(1), in1->in(2));
282 }
283 }
284
285 // Convert "x+(0-y)" into "(x-y)"
286 if( op2 == Op_SubI && phase->type(in2->in(1)) == TypeInt::ZERO )
287 return new (phase->C) SubINode(in1, in2->in(2) );
288
289 // Convert "(0-y)+x" into "(x-y)"
290 if( op1 == Op_SubI && phase->type(in1->in(1)) == TypeInt::ZERO )
291 return new (phase->C) SubINode( in2, in1->in(2) );
292
293 // Convert (x>>>z)+y into (x+(y<<z))>>>z for small constant z and y.
294 // Helps with array allocation math constant folding
295 // See 4790063:
296 // Unrestricted transformation is unsafe for some runtime values of 'x'
297 // ( x == 0, z == 1, y == -1 ) fails
298 // ( x == -5, z == 1, y == 1 ) fails
299 // Transform works for small z and small negative y when the addition
300 // (x + (y << z)) does not cross zero.
301 // Implement support for negative y and (x >= -(y << z))
302 // Have not observed cases where type information exists to support
303 // positive y and (x <= -(y << z))
304 if( op1 == Op_URShiftI && op2 == Op_ConI &&
305 in1->in(2)->Opcode() == Op_ConI ) {
306 jint z = phase->type( in1->in(2) )->is_int()->get_con() & 0x1f; // only least significant 5 bits matter
307 jint y = phase->type( in2 )->is_int()->get_con();
308
309 if( z < 5 && -5 < y && y < 0 ) {
310 const Type *t_in11 = phase->type(in1->in(1));
311 if( t_in11 != Type::TOP && (t_in11->is_int()->_lo >= -(y << z)) ) {
312 Node *a = phase->transform( new (phase->C) AddINode( in1->in(1), phase->intcon(y<<z) ) );
313 return new (phase->C) URShiftINode( a, in1->in(2) );
314 }
315 }
316 }
317
318 return AddNode::Ideal(phase, can_reshape);
319 }
320
321
322 //------------------------------Identity---------------------------------------
323 // Fold (x-y)+y OR y+(x-y) into x
324 Node *AddINode::Identity( PhaseTransform *phase ) {
325 if( in(1)->Opcode() == Op_SubI && phase->eqv(in(1)->in(2),in(2)) ) {
326 return in(1)->in(1);
327 }
328 else if( in(2)->Opcode() == Op_SubI && phase->eqv(in(2)->in(2),in(1)) ) {
329 return in(2)->in(1);
330 }
331 return AddNode::Identity(phase);
332 }
333
334
335 //------------------------------add_ring---------------------------------------
336 // Supplied function returns the sum of the inputs. Guaranteed never
337 // to be passed a TOP or BOTTOM type, these are filtered out by
338 // pre-check.
339 const Type *AddINode::add_ring( const Type *t0, const Type *t1 ) const {
340 const TypeInt *r0 = t0->is_int(); // Handy access
341 const TypeInt *r1 = t1->is_int();
342 int lo = r0->_lo + r1->_lo;
343 int hi = r0->_hi + r1->_hi;
344 if( !(r0->is_con() && r1->is_con()) ) {
345 // Not both constants, compute approximate result
346 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
347 lo = min_jint; hi = max_jint; // Underflow on the low side
348 }
349 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
350 lo = min_jint; hi = max_jint; // Overflow on the high side
351 }
352 if( lo > hi ) { // Handle overflow
353 lo = min_jint; hi = max_jint;
354 }
355 } else {
356 // both constants, compute precise result using 'lo' and 'hi'
357 // Semantics define overflow and underflow for integer addition
358 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
359 }
360 return TypeInt::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
361 }
362
363
364 //=============================================================================
365 //------------------------------Idealize---------------------------------------
366 Node *AddLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
367 Node* in1 = in(1);
368 Node* in2 = in(2);
369 int op1 = in1->Opcode();
370 int op2 = in2->Opcode();
371 // Fold (con1-x)+con2 into (con1+con2)-x
372 if ( op1 == Op_AddL && op2 == Op_SubL ) {
373 // Swap edges to try optimizations below
374 in1 = in2;
375 in2 = in(1);
376 op1 = op2;
377 op2 = in2->Opcode();
378 }
379 // Fold (con1-x)+con2 into (con1+con2)-x
380 if( op1 == Op_SubL ) {
381 const Type *t_sub1 = phase->type( in1->in(1) );
382 const Type *t_2 = phase->type( in2 );
383 if( t_sub1->singleton() && t_2->singleton() && t_sub1 != Type::TOP && t_2 != Type::TOP )
384 return new (phase->C) SubLNode(phase->makecon( add_ring( t_sub1, t_2 ) ),
385 in1->in(2) );
386 // Convert "(a-b)+(c-d)" into "(a+c)-(b+d)"
387 if( op2 == Op_SubL ) {
388 // Check for dead cycle: d = (a-b)+(c-d)
389 assert( in1->in(2) != this && in2->in(2) != this,
390 "dead loop in AddLNode::Ideal" );
391 Node *sub = new (phase->C) SubLNode(NULL, NULL);
392 sub->init_req(1, phase->transform(new (phase->C) AddLNode(in1->in(1), in2->in(1) ) ));
393 sub->init_req(2, phase->transform(new (phase->C) AddLNode(in1->in(2), in2->in(2) ) ));
394 return sub;
395 }
396 // Convert "(a-b)+(b+c)" into "(a+c)"
397 if( op2 == Op_AddL && in1->in(2) == in2->in(1) ) {
398 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddLNode::Ideal");
399 return new (phase->C) AddLNode(in1->in(1), in2->in(2));
400 }
401 // Convert "(a-b)+(c+b)" into "(a+c)"
402 if( op2 == Op_AddL && in1->in(2) == in2->in(2) ) {
403 assert(in1->in(1) != this && in2->in(1) != this,"dead loop in AddLNode::Ideal");
404 return new (phase->C) AddLNode(in1->in(1), in2->in(1));
405 }
406 // Convert "(a-b)+(b-c)" into "(a-c)"
407 if( op2 == Op_SubL && in1->in(2) == in2->in(1) ) {
408 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddLNode::Ideal");
409 return new (phase->C) SubLNode(in1->in(1), in2->in(2));
410 }
411 // Convert "(a-b)+(c-a)" into "(c-b)"
412 if( op2 == Op_SubL && in1->in(1) == in1->in(2) ) {
413 assert(in1->in(2) != this && in2->in(1) != this,"dead loop in AddLNode::Ideal");
414 return new (phase->C) SubLNode(in2->in(1), in1->in(2));
415 }
416 }
417
418 // Convert "x+(0-y)" into "(x-y)"
419 if( op2 == Op_SubL && phase->type(in2->in(1)) == TypeLong::ZERO )
420 return new (phase->C) SubLNode( in1, in2->in(2) );
421
422 // Convert "(0-y)+x" into "(x-y)"
423 if( op1 == Op_SubL && phase->type(in1->in(1)) == TypeInt::ZERO )
424 return new (phase->C) SubLNode( in2, in1->in(2) );
425
426 // Convert "X+X+X+X+X...+X+Y" into "k*X+Y" or really convert "X+(X+Y)"
427 // into "(X<<1)+Y" and let shift-folding happen.
428 if( op2 == Op_AddL &&
429 in2->in(1) == in1 &&
430 op1 != Op_ConL &&
431 0 ) {
432 Node *shift = phase->transform(new (phase->C) LShiftLNode(in1,phase->intcon(1)));
433 return new (phase->C) AddLNode(shift,in2->in(2));
434 }
435
436 return AddNode::Ideal(phase, can_reshape);
437 }
438
439
440 //------------------------------Identity---------------------------------------
441 // Fold (x-y)+y OR y+(x-y) into x
442 Node *AddLNode::Identity( PhaseTransform *phase ) {
443 if( in(1)->Opcode() == Op_SubL && phase->eqv(in(1)->in(2),in(2)) ) {
444 return in(1)->in(1);
445 }
446 else if( in(2)->Opcode() == Op_SubL && phase->eqv(in(2)->in(2),in(1)) ) {
447 return in(2)->in(1);
448 }
449 return AddNode::Identity(phase);
450 }
451
452
453 //------------------------------add_ring---------------------------------------
454 // Supplied function returns the sum of the inputs. Guaranteed never
455 // to be passed a TOP or BOTTOM type, these are filtered out by
456 // pre-check.
457 const Type *AddLNode::add_ring( const Type *t0, const Type *t1 ) const {
458 const TypeLong *r0 = t0->is_long(); // Handy access
459 const TypeLong *r1 = t1->is_long();
460 jlong lo = r0->_lo + r1->_lo;
461 jlong hi = r0->_hi + r1->_hi;
462 if( !(r0->is_con() && r1->is_con()) ) {
463 // Not both constants, compute approximate result
464 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
465 lo =min_jlong; hi = max_jlong; // Underflow on the low side
466 }
467 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
468 lo = min_jlong; hi = max_jlong; // Overflow on the high side
469 }
470 if( lo > hi ) { // Handle overflow
471 lo = min_jlong; hi = max_jlong;
472 }
473 } else {
474 // both constants, compute precise result using 'lo' and 'hi'
475 // Semantics define overflow and underflow for integer addition
476 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
477 }
478 return TypeLong::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
479 }
480
481
482 //=============================================================================
483 //------------------------------add_of_identity--------------------------------
484 // Check for addition of the identity
485 const Type *AddFNode::add_of_identity( const Type *t1, const Type *t2 ) const {
486 // x ADD 0 should return x unless 'x' is a -zero
487 //
488 // const Type *zero = add_id(); // The additive identity
489 // jfloat f1 = t1->getf();
490 // jfloat f2 = t2->getf();
491 //
492 // if( t1->higher_equal( zero ) ) return t2;
493 // if( t2->higher_equal( zero ) ) return t1;
494
495 return NULL;
496 }
497
498 //------------------------------add_ring---------------------------------------
499 // Supplied function returns the sum of the inputs.
500 // This also type-checks the inputs for sanity. Guaranteed never to
501 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
502 const Type *AddFNode::add_ring( const Type *t0, const Type *t1 ) const {
503 // We must be adding 2 float constants.
504 return TypeF::make( t0->getf() + t1->getf() );
505 }
506
507 //------------------------------Ideal------------------------------------------
508 Node *AddFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
509 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
510 return AddNode::Ideal(phase, can_reshape); // commutative and associative transforms
511 }
512
513 // Floating point additions are not associative because of boundary conditions (infinity)
514 return commute(this,
515 phase->type( in(1) )->singleton(),
516 phase->type( in(2) )->singleton() ) ? this : NULL;
517 }
518
519
520 //=============================================================================
521 //------------------------------add_of_identity--------------------------------
522 // Check for addition of the identity
523 const Type *AddDNode::add_of_identity( const Type *t1, const Type *t2 ) const {
524 // x ADD 0 should return x unless 'x' is a -zero
525 //
526 // const Type *zero = add_id(); // The additive identity
527 // jfloat f1 = t1->getf();
528 // jfloat f2 = t2->getf();
529 //
530 // if( t1->higher_equal( zero ) ) return t2;
531 // if( t2->higher_equal( zero ) ) return t1;
532
533 return NULL;
534 }
535 //------------------------------add_ring---------------------------------------
536 // Supplied function returns the sum of the inputs.
537 // This also type-checks the inputs for sanity. Guaranteed never to
538 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
539 const Type *AddDNode::add_ring( const Type *t0, const Type *t1 ) const {
540 // We must be adding 2 double constants.
541 return TypeD::make( t0->getd() + t1->getd() );
542 }
543
544 //------------------------------Ideal------------------------------------------
545 Node *AddDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
546 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
547 return AddNode::Ideal(phase, can_reshape); // commutative and associative transforms
548 }
549
550 // Floating point additions are not associative because of boundary conditions (infinity)
551 return commute(this,
552 phase->type( in(1) )->singleton(),
553 phase->type( in(2) )->singleton() ) ? this : NULL;
554 }
555
556
557 //=============================================================================
558 //------------------------------Identity---------------------------------------
559 // If one input is a constant 0, return the other input.
560 Node *AddPNode::Identity( PhaseTransform *phase ) {
561 return ( phase->type( in(Offset) )->higher_equal( TypeX_ZERO ) ) ? in(Address) : this;
562 }
563
564 //------------------------------Idealize---------------------------------------
565 Node *AddPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
566 // Bail out if dead inputs
567 if( phase->type( in(Address) ) == Type::TOP ) return NULL;
568
569 // If the left input is an add of a constant, flatten the expression tree.
570 const Node *n = in(Address);
571 if (n->is_AddP() && n->in(Base) == in(Base)) {
572 const AddPNode *addp = n->as_AddP(); // Left input is an AddP
573 assert( !addp->in(Address)->is_AddP() ||
574 addp->in(Address)->as_AddP() != addp,
575 "dead loop in AddPNode::Ideal" );
576 // Type of left input's right input
577 const Type *t = phase->type( addp->in(Offset) );
578 if( t == Type::TOP ) return NULL;
579 const TypeX *t12 = t->is_intptr_t();
580 if( t12->is_con() ) { // Left input is an add of a constant?
581 // If the right input is a constant, combine constants
582 const Type *temp_t2 = phase->type( in(Offset) );
583 if( temp_t2 == Type::TOP ) return NULL;
584 const TypeX *t2 = temp_t2->is_intptr_t();
585 Node* address;
586 Node* offset;
587 if( t2->is_con() ) {
588 // The Add of the flattened expression
589 address = addp->in(Address);
590 offset = phase->MakeConX(t2->get_con() + t12->get_con());
591 } else {
592 // Else move the constant to the right. ((A+con)+B) into ((A+B)+con)
593 address = phase->transform(new (phase->C) AddPNode(in(Base),addp->in(Address),in(Offset)));
594 offset = addp->in(Offset);
595 }
596 PhaseIterGVN *igvn = phase->is_IterGVN();
597 if( igvn ) {
598 set_req_X(Address,address,igvn);
599 set_req_X(Offset,offset,igvn);
600 } else {
601 set_req(Address,address);
602 set_req(Offset,offset);
603 }
604 return this;
605 }
606 }
607
608 // Raw pointers?
609 if( in(Base)->bottom_type() == Type::TOP ) {
610 // If this is a NULL+long form (from unsafe accesses), switch to a rawptr.
611 if (phase->type(in(Address)) == TypePtr::NULL_PTR) {
612 Node* offset = in(Offset);
613 return new (phase->C) CastX2PNode(offset);
614 }
615 }
616
617 // If the right is an add of a constant, push the offset down.
618 // Convert: (ptr + (offset+con)) into (ptr+offset)+con.
619 // The idea is to merge array_base+scaled_index groups together,
620 // and only have different constant offsets from the same base.
621 const Node *add = in(Offset);
622 if( add->Opcode() == Op_AddX && add->in(1) != add ) {
623 const Type *t22 = phase->type( add->in(2) );
624 if( t22->singleton() && (t22 != Type::TOP) ) { // Right input is an add of a constant?
625 set_req(Address, phase->transform(new (phase->C) AddPNode(in(Base),in(Address),add->in(1))));
626 set_req(Offset, add->in(2));
627 return this; // Made progress
628 }
629 }
630
631 return NULL; // No progress
632 }
633
634 //------------------------------bottom_type------------------------------------
635 // Bottom-type is the pointer-type with unknown offset.
636 const Type *AddPNode::bottom_type() const {
637 if (in(Address) == NULL) return TypePtr::BOTTOM;
638 const TypePtr *tp = in(Address)->bottom_type()->isa_ptr();
639 if( !tp ) return Type::TOP; // TOP input means TOP output
640 assert( in(Offset)->Opcode() != Op_ConP, "" );
641 const Type *t = in(Offset)->bottom_type();
642 if( t == Type::TOP )
643 return tp->add_offset(Type::OffsetTop);
644 const TypeX *tx = t->is_intptr_t();
645 intptr_t txoffset = Type::OffsetBot;
646 if (tx->is_con()) { // Left input is an add of a constant?
647 txoffset = tx->get_con();
648 }
649 return tp->add_offset(txoffset);
650 }
651
652 //------------------------------Value------------------------------------------
653 const Type *AddPNode::Value( PhaseTransform *phase ) const {
654 // Either input is TOP ==> the result is TOP
655 const Type *t1 = phase->type( in(Address) );
656 const Type *t2 = phase->type( in(Offset) );
657 if( t1 == Type::TOP ) return Type::TOP;
658 if( t2 == Type::TOP ) return Type::TOP;
659
660 // Left input is a pointer
661 const TypePtr *p1 = t1->isa_ptr();
662 // Right input is an int
663 const TypeX *p2 = t2->is_intptr_t();
664 // Add 'em
665 intptr_t p2offset = Type::OffsetBot;
666 if (p2->is_con()) { // Left input is an add of a constant?
667 p2offset = p2->get_con();
668 }
669 return p1->add_offset(p2offset);
670 }
671
672 //------------------------Ideal_base_and_offset--------------------------------
673 // Split an oop pointer into a base and offset.
674 // (The offset might be Type::OffsetBot in the case of an array.)
675 // Return the base, or NULL if failure.
676 Node* AddPNode::Ideal_base_and_offset(Node* ptr, PhaseTransform* phase,
677 // second return value:
678 intptr_t& offset) {
679 if (ptr->is_AddP()) {
680 Node* base = ptr->in(AddPNode::Base);
681 Node* addr = ptr->in(AddPNode::Address);
682 Node* offs = ptr->in(AddPNode::Offset);
683 if (base == addr || base->is_top()) {
684 offset = phase->find_intptr_t_con(offs, Type::OffsetBot);
685 if (offset != Type::OffsetBot) {
686 return addr;
687 }
688 }
689 }
690 offset = Type::OffsetBot;
691 return NULL;
692 }
693
694 //------------------------------unpack_offsets----------------------------------
695 // Collect the AddP offset values into the elements array, giving up
696 // if there are more than length.
697 int AddPNode::unpack_offsets(Node* elements[], int length) {
698 int count = 0;
699 Node* addr = this;
700 Node* base = addr->in(AddPNode::Base);
701 while (addr->is_AddP()) {
702 if (addr->in(AddPNode::Base) != base) {
703 // give up
704 return -1;
705 }
706 elements[count++] = addr->in(AddPNode::Offset);
707 if (count == length) {
708 // give up
709 return -1;
710 }
711 addr = addr->in(AddPNode::Address);
712 }
713 if (addr != base) {
714 return -1;
715 }
716 return count;
717 }
718
719 //------------------------------match_edge-------------------------------------
720 // Do we Match on this edge index or not? Do not match base pointer edge
721 uint AddPNode::match_edge(uint idx) const {
722 return idx > Base;
723 }
724
725 //=============================================================================
726 //------------------------------Identity---------------------------------------
727 Node *OrINode::Identity( PhaseTransform *phase ) {
728 // x | x => x
729 if (phase->eqv(in(1), in(2))) {
730 return in(1);
731 }
732
733 return AddNode::Identity(phase);
734 }
735
736 //------------------------------add_ring---------------------------------------
737 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
738 // the logical operations the ring's ADD is really a logical OR function.
739 // This also type-checks the inputs for sanity. Guaranteed never to
740 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
741 const Type *OrINode::add_ring( const Type *t0, const Type *t1 ) const {
742 const TypeInt *r0 = t0->is_int(); // Handy access
743 const TypeInt *r1 = t1->is_int();
744
745 // If both args are bool, can figure out better types
746 if ( r0 == TypeInt::BOOL ) {
747 if ( r1 == TypeInt::ONE) {
748 return TypeInt::ONE;
749 } else if ( r1 == TypeInt::BOOL ) {
750 return TypeInt::BOOL;
751 }
752 } else if ( r0 == TypeInt::ONE ) {
753 if ( r1 == TypeInt::BOOL ) {
754 return TypeInt::ONE;
755 }
756 }
757
758 // If either input is not a constant, just return all integers.
759 if( !r0->is_con() || !r1->is_con() )
760 return TypeInt::INT; // Any integer, but still no symbols.
761
762 // Otherwise just OR them bits.
763 return TypeInt::make( r0->get_con() | r1->get_con() );
764 }
765
766 //=============================================================================
767 //------------------------------Identity---------------------------------------
768 Node *OrLNode::Identity( PhaseTransform *phase ) {
769 // x | x => x
770 if (phase->eqv(in(1), in(2))) {
771 return in(1);
772 }
773
774 return AddNode::Identity(phase);
775 }
776
777 //------------------------------add_ring---------------------------------------
778 const Type *OrLNode::add_ring( const Type *t0, const Type *t1 ) const {
779 const TypeLong *r0 = t0->is_long(); // Handy access
780 const TypeLong *r1 = t1->is_long();
781
782 // If either input is not a constant, just return all integers.
783 if( !r0->is_con() || !r1->is_con() )
784 return TypeLong::LONG; // Any integer, but still no symbols.
785
786 // Otherwise just OR them bits.
787 return TypeLong::make( r0->get_con() | r1->get_con() );
788 }
789
790 //=============================================================================
791 //------------------------------add_ring---------------------------------------
792 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
793 // the logical operations the ring's ADD is really a logical OR function.
794 // This also type-checks the inputs for sanity. Guaranteed never to
795 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
796 const Type *XorINode::add_ring( const Type *t0, const Type *t1 ) const {
797 const TypeInt *r0 = t0->is_int(); // Handy access
798 const TypeInt *r1 = t1->is_int();
799
800 // Complementing a boolean?
801 if( r0 == TypeInt::BOOL && ( r1 == TypeInt::ONE
802 || r1 == TypeInt::BOOL))
803 return TypeInt::BOOL;
804
805 if( !r0->is_con() || !r1->is_con() ) // Not constants
806 return TypeInt::INT; // Any integer, but still no symbols.
807
808 // Otherwise just XOR them bits.
809 return TypeInt::make( r0->get_con() ^ r1->get_con() );
810 }
811
812 //=============================================================================
813 //------------------------------add_ring---------------------------------------
814 const Type *XorLNode::add_ring( const Type *t0, const Type *t1 ) const {
815 const TypeLong *r0 = t0->is_long(); // Handy access
816 const TypeLong *r1 = t1->is_long();
817
818 // If either input is not a constant, just return all integers.
819 if( !r0->is_con() || !r1->is_con() )
820 return TypeLong::LONG; // Any integer, but still no symbols.
821
822 // Otherwise just OR them bits.
823 return TypeLong::make( r0->get_con() ^ r1->get_con() );
824 }
825
826 //=============================================================================
827 //------------------------------add_ring---------------------------------------
828 // Supplied function returns the sum of the inputs.
829 const Type *MaxINode::add_ring( const Type *t0, const Type *t1 ) const {
830 const TypeInt *r0 = t0->is_int(); // Handy access
831 const TypeInt *r1 = t1->is_int();
832
833 // Otherwise just MAX them bits.
834 return TypeInt::make( MAX2(r0->_lo,r1->_lo), MAX2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
835 }
836
837 //=============================================================================
838 //------------------------------Idealize---------------------------------------
839 // MINs show up in range-check loop limit calculations. Look for
840 // "MIN2(x+c0,MIN2(y,x+c1))". Pick the smaller constant: "MIN2(x+c0,y)"
841 Node *MinINode::Ideal(PhaseGVN *phase, bool can_reshape) {
842 Node *progress = NULL;
843 // Force a right-spline graph
844 Node *l = in(1);
845 Node *r = in(2);
846 // Transform MinI1( MinI2(a,b), c) into MinI1( a, MinI2(b,c) )
847 // to force a right-spline graph for the rest of MinINode::Ideal().
848 if( l->Opcode() == Op_MinI ) {
849 assert( l != l->in(1), "dead loop in MinINode::Ideal" );
850 r = phase->transform(new (phase->C) MinINode(l->in(2),r));
851 l = l->in(1);
852 set_req(1, l);
853 set_req(2, r);
854 return this;
855 }
856
857 // Get left input & constant
858 Node *x = l;
859 int x_off = 0;
860 if( x->Opcode() == Op_AddI && // Check for "x+c0" and collect constant
861 x->in(2)->is_Con() ) {
862 const Type *t = x->in(2)->bottom_type();
863 if( t == Type::TOP ) return NULL; // No progress
864 x_off = t->is_int()->get_con();
865 x = x->in(1);
866 }
867
868 // Scan a right-spline-tree for MINs
869 Node *y = r;
870 int y_off = 0;
871 // Check final part of MIN tree
872 if( y->Opcode() == Op_AddI && // Check for "y+c1" and collect constant
873 y->in(2)->is_Con() ) {
874 const Type *t = y->in(2)->bottom_type();
875 if( t == Type::TOP ) return NULL; // No progress
876 y_off = t->is_int()->get_con();
877 y = y->in(1);
878 }
879 if( x->_idx > y->_idx && r->Opcode() != Op_MinI ) {
880 swap_edges(1, 2);
881 return this;
882 }
883
884
885 if( r->Opcode() == Op_MinI ) {
886 assert( r != r->in(2), "dead loop in MinINode::Ideal" );
887 y = r->in(1);
888 // Check final part of MIN tree
889 if( y->Opcode() == Op_AddI &&// Check for "y+c1" and collect constant
890 y->in(2)->is_Con() ) {
891 const Type *t = y->in(2)->bottom_type();
892 if( t == Type::TOP ) return NULL; // No progress
893 y_off = t->is_int()->get_con();
894 y = y->in(1);
895 }
896
897 if( x->_idx > y->_idx )
898 return new (phase->C) MinINode(r->in(1),phase->transform(new (phase->C) MinINode(l,r->in(2))));
899
900 // See if covers: MIN2(x+c0,MIN2(y+c1,z))
901 if( !phase->eqv(x,y) ) return NULL;
902 // If (y == x) transform MIN2(x+c0, MIN2(x+c1,z)) into
903 // MIN2(x+c0 or x+c1 which less, z).
904 return new (phase->C) MinINode(phase->transform(new (phase->C) AddINode(x,phase->intcon(MIN2(x_off,y_off)))),r->in(2));
905 } else {
906 // See if covers: MIN2(x+c0,y+c1)
907 if( !phase->eqv(x,y) ) return NULL;
908 // If (y == x) transform MIN2(x+c0,x+c1) into x+c0 or x+c1 which less.
909 return new (phase->C) AddINode(x,phase->intcon(MIN2(x_off,y_off)));
910 }
911
912 }
913
914 //------------------------------add_ring---------------------------------------
915 // Supplied function returns the sum of the inputs.
916 const Type *MinINode::add_ring( const Type *t0, const Type *t1 ) const {
917 const TypeInt *r0 = t0->is_int(); // Handy access
918 const TypeInt *r1 = t1->is_int();
919
920 // Otherwise just MIN them bits.
921 return TypeInt::make( MIN2(r0->_lo,r1->_lo), MIN2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
922 }