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.
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 #define MAXFLOAT ((float)3.40282346638528860e+38)
38
39 // Classic Add functionality. This covers all the usual 'add' behaviors for
40 // an algebraic ring. Add-integer, add-float, add-double, and binary-or are
41 // all inherited from this class. The various identity values are supplied
42 // by virtual functions.
43
44
45 //=============================================================================
46 //------------------------------hash-------------------------------------------
47 // Hash function over AddNodes. Needs to be commutative; i.e., I swap
48 // (commute) inputs to AddNodes willy-nilly so the hash function must return
49 // the same value in the presence of edge swapping.
50 uint AddNode::hash() const {
51 return (uintptr_t)in(1) + (uintptr_t)in(2) + Opcode();
52 }
53
54 //------------------------------Identity---------------------------------------
55 // If either input is a constant 0, return the other input.
56 Node *AddNode::Identity( PhaseTransform *phase ) {
57 const Type *zero = add_id(); // The additive identity
58 if( phase->type( in(1) )->higher_equal( zero ) ) return in(2);
59 if( phase->type( in(2) )->higher_equal( zero ) ) return in(1);
60 return this;
61 }
62
63 //------------------------------commute----------------------------------------
64 // Commute operands to move loads and constants to the right.
65 static bool commute( Node *add, int con_left, int con_right ) {
66 Node *in1 = add->in(1);
67 Node *in2 = add->in(2);
68
69 // Convert "1+x" into "x+1".
70 // Right is a constant; leave it
71 if( con_right ) return false;
72 // Left is a constant; move it right.
73 if( con_left ) {
74 add->swap_edges(1, 2);
75 return true;
76 }
77
78 // Convert "Load+x" into "x+Load".
79 // Now check for loads
80 if (in2->is_Load()) {
81 if (!in1->is_Load()) {
82 // already x+Load to return
83 return false;
84 }
85 // both are loads, so fall through to sort inputs by idx
86 } else if( in1->is_Load() ) {
87 // Left is a Load and Right is not; move it right.
88 add->swap_edges(1, 2);
89 return true;
90 }
91
92 PhiNode *phi;
93 // Check for tight loop increments: Loop-phi of Add of loop-phi
94 if( in1->is_Phi() && (phi = in1->as_Phi()) && !phi->is_copy() && phi->region()->is_Loop() && phi->in(2)==add)
95 return false;
96 if( in2->is_Phi() && (phi = in2->as_Phi()) && !phi->is_copy() && phi->region()->is_Loop() && phi->in(2)==add){
97 add->swap_edges(1, 2);
98 return true;
99 }
100
101 // Otherwise, sort inputs (commutativity) to help value numbering.
102 if( in1->_idx > in2->_idx ) {
103 add->swap_edges(1, 2);
104 return true;
105 }
106 return false;
107 }
108
109 //------------------------------Idealize---------------------------------------
110 // If we get here, we assume we are associative!
111 Node *AddNode::Ideal(PhaseGVN *phase, bool can_reshape) {
112 const Type *t1 = phase->type( in(1) );
113 const Type *t2 = phase->type( in(2) );
114 int con_left = t1->singleton();
115 int con_right = t2->singleton();
116
117 // Check for commutative operation desired
118 if( commute(this,con_left,con_right) ) return this;
119
120 AddNode *progress = NULL; // Progress flag
121
122 // Convert "(x+1)+2" into "x+(1+2)". If the right input is a
123 // constant, and the left input is an add of a constant, flatten the
124 // expression tree.
125 Node *add1 = in(1);
126 Node *add2 = in(2);
127 int add1_op = add1->Opcode();
128 int this_op = Opcode();
129 if( con_right && t2 != Type::TOP && // Right input is a constant?
130 add1_op == this_op ) { // Left input is an Add?
131
132 // Type of left _in right input
133 const Type *t12 = phase->type( add1->in(2) );
134 if( t12->singleton() && t12 != Type::TOP ) { // Left input is an add of a constant?
135 // Check for rare case of closed data cycle which can happen inside
136 // unreachable loops. In these cases the computation is undefined.
137 #ifdef ASSERT
138 Node *add11 = add1->in(1);
139 int add11_op = add11->Opcode();
140 if( (add1 == add1->in(1))
141 || (add11_op == this_op && add11->in(1) == add1) ) {
142 assert(false, "dead loop in AddNode::Ideal");
143 }
144 #endif
145 // The Add of the flattened expression
146 Node *x1 = add1->in(1);
147 Node *x2 = phase->makecon( add1->as_Add()->add_ring( t2, t12 ));
148 PhaseIterGVN *igvn = phase->is_IterGVN();
149 if( igvn ) {
150 set_req_X(2,x2,igvn);
151 set_req_X(1,x1,igvn);
152 } else {
153 set_req(2,x2);
154 set_req(1,x1);
155 }
156 progress = this; // Made progress
157 add1 = in(1);
158 add1_op = add1->Opcode();
159 }
160 }
161
162 // Convert "(x+1)+y" into "(x+y)+1". Push constants down the expression tree.
163 if( add1_op == this_op && !con_right ) {
164 Node *a12 = add1->in(2);
165 const Type *t12 = phase->type( a12 );
166 if( t12->singleton() && t12 != Type::TOP && (add1 != add1->in(1)) &&
167 !(add1->in(1)->is_Phi() && add1->in(1)->as_Phi()->is_tripcount()) ) {
168 assert(add1->in(1) != this, "dead loop in AddNode::Ideal");
169 add2 = add1->clone();
170 add2->set_req(2, in(2));
171 add2 = phase->transform(add2);
172 set_req(1, add2);
173 set_req(2, a12);
174 progress = this;
175 add2 = a12;
176 }
177 }
178
179 // Convert "x+(y+1)" into "(x+y)+1". Push constants down the expression tree.
180 int add2_op = add2->Opcode();
181 if( add2_op == this_op && !con_left ) {
182 Node *a22 = add2->in(2);
183 const Type *t22 = phase->type( a22 );
184 if( t22->singleton() && t22 != Type::TOP && (add2 != add2->in(1)) &&
185 !(add2->in(1)->is_Phi() && add2->in(1)->as_Phi()->is_tripcount()) ) {
186 assert(add2->in(1) != this, "dead loop in AddNode::Ideal");
187 Node *addx = add2->clone();
188 addx->set_req(1, in(1));
189 addx->set_req(2, add2->in(1));
190 addx = phase->transform(addx);
191 set_req(1, addx);
192 set_req(2, a22);
193 progress = this;
194 }
195 }
196
197 return progress;
198 }
199
200 //------------------------------Value-----------------------------------------
201 // An add node sums it's two _in. If one input is an RSD, we must mixin
202 // the other input's symbols.
203 const Type *AddNode::Value( PhaseTransform *phase ) const {
204 // Either input is TOP ==> the result is TOP
205 const Type *t1 = phase->type( in(1) );
206 const Type *t2 = phase->type( in(2) );
207 if( t1 == Type::TOP ) return Type::TOP;
208 if( t2 == Type::TOP ) return Type::TOP;
209
210 // Either input is BOTTOM ==> the result is the local BOTTOM
211 const Type *bot = bottom_type();
212 if( (t1 == bot) || (t2 == bot) ||
213 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
214 return bot;
215
216 // Check for an addition involving the additive identity
217 const Type *tadd = add_of_identity( t1, t2 );
218 if( tadd ) return tadd;
219
220 return add_ring(t1,t2); // Local flavor of type addition
221 }
222
223 //------------------------------add_identity-----------------------------------
224 // Check for addition of the identity
225 const Type *AddNode::add_of_identity( const Type *t1, const Type *t2 ) const {
226 const Type *zero = add_id(); // The additive identity
227 if( t1->higher_equal( zero ) ) return t2;
228 if( t2->higher_equal( zero ) ) return t1;
229
230 return NULL;
231 }
232
233
234 //=============================================================================
235 //------------------------------Idealize---------------------------------------
236 Node *AddINode::Ideal(PhaseGVN *phase, bool can_reshape) {
237 Node* in1 = in(1);
238 Node* in2 = in(2);
239 int op1 = in1->Opcode();
240 int op2 = in2->Opcode();
241 // Fold (con1-x)+con2 into (con1+con2)-x
242 if ( op1 == Op_AddI && op2 == Op_SubI ) {
243 // Swap edges to try optimizations below
244 in1 = in2;
245 in2 = in(1);
246 op1 = op2;
247 op2 = in2->Opcode();
248 }
249 if( op1 == Op_SubI ) {
250 const Type *t_sub1 = phase->type( in1->in(1) );
251 const Type *t_2 = phase->type( in2 );
252 if( t_sub1->singleton() && t_2->singleton() && t_sub1 != Type::TOP && t_2 != Type::TOP )
253 return new (phase->C, 3) SubINode(phase->makecon( add_ring( t_sub1, t_2 ) ),
254 in1->in(2) );
255 // Convert "(a-b)+(c-d)" into "(a+c)-(b+d)"
256 if( op2 == Op_SubI ) {
257 // Check for dead cycle: d = (a-b)+(c-d)
258 assert( in1->in(2) != this && in2->in(2) != this,
259 "dead loop in AddINode::Ideal" );
260 Node *sub = new (phase->C, 3) SubINode(NULL, NULL);
261 sub->init_req(1, phase->transform(new (phase->C, 3) AddINode(in1->in(1), in2->in(1) ) ));
262 sub->init_req(2, phase->transform(new (phase->C, 3) AddINode(in1->in(2), in2->in(2) ) ));
263 return sub;
264 }
265 // Convert "(a-b)+(b+c)" into "(a+c)"
266 if( op2 == Op_AddI && in1->in(2) == in2->in(1) ) {
267 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddINode::Ideal");
268 return new (phase->C, 3) AddINode(in1->in(1), in2->in(2));
269 }
270 // Convert "(a-b)+(c+b)" into "(a+c)"
271 if( op2 == Op_AddI && in1->in(2) == in2->in(2) ) {
272 assert(in1->in(1) != this && in2->in(1) != this,"dead loop in AddINode::Ideal");
273 return new (phase->C, 3) AddINode(in1->in(1), in2->in(1));
274 }
275 // Convert "(a-b)+(b-c)" into "(a-c)"
276 if( op2 == Op_SubI && in1->in(2) == in2->in(1) ) {
277 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddINode::Ideal");
278 return new (phase->C, 3) SubINode(in1->in(1), in2->in(2));
279 }
280 // Convert "(a-b)+(c-a)" into "(c-b)"
281 if( op2 == Op_SubI && in1->in(1) == in2->in(2) ) {
282 assert(in1->in(2) != this && in2->in(1) != this,"dead loop in AddINode::Ideal");
283 return new (phase->C, 3) SubINode(in2->in(1), in1->in(2));
284 }
285 }
286
287 // Convert "x+(0-y)" into "(x-y)"
288 if( op2 == Op_SubI && phase->type(in2->in(1)) == TypeInt::ZERO )
289 return new (phase->C, 3) SubINode(in1, in2->in(2) );
290
291 // Convert "(0-y)+x" into "(x-y)"
292 if( op1 == Op_SubI && phase->type(in1->in(1)) == TypeInt::ZERO )
293 return new (phase->C, 3) SubINode( in2, in1->in(2) );
294
295 // Convert (x>>>z)+y into (x+(y<<z))>>>z for small constant z and y.
296 // Helps with array allocation math constant folding
297 // See 4790063:
298 // Unrestricted transformation is unsafe for some runtime values of 'x'
299 // ( x == 0, z == 1, y == -1 ) fails
300 // ( x == -5, z == 1, y == 1 ) fails
301 // Transform works for small z and small negative y when the addition
302 // (x + (y << z)) does not cross zero.
303 // Implement support for negative y and (x >= -(y << z))
304 // Have not observed cases where type information exists to support
305 // positive y and (x <= -(y << z))
306 if( op1 == Op_URShiftI && op2 == Op_ConI &&
307 in1->in(2)->Opcode() == Op_ConI ) {
308 jint z = phase->type( in1->in(2) )->is_int()->get_con() & 0x1f; // only least significant 5 bits matter
309 jint y = phase->type( in2 )->is_int()->get_con();
310
311 if( z < 5 && -5 < y && y < 0 ) {
312 const Type *t_in11 = phase->type(in1->in(1));
313 if( t_in11 != Type::TOP && (t_in11->is_int()->_lo >= -(y << z)) ) {
314 Node *a = phase->transform( new (phase->C, 3) AddINode( in1->in(1), phase->intcon(y<<z) ) );
315 return new (phase->C, 3) URShiftINode( a, in1->in(2) );
316 }
317 }
318 }
319
320 return AddNode::Ideal(phase, can_reshape);
321 }
322
323
324 //------------------------------Identity---------------------------------------
325 // Fold (x-y)+y OR y+(x-y) into x
326 Node *AddINode::Identity( PhaseTransform *phase ) {
327 if( in(1)->Opcode() == Op_SubI && phase->eqv(in(1)->in(2),in(2)) ) {
328 return in(1)->in(1);
329 }
330 else if( in(2)->Opcode() == Op_SubI && phase->eqv(in(2)->in(2),in(1)) ) {
331 return in(2)->in(1);
332 }
333 return AddNode::Identity(phase);
334 }
335
336
337 //------------------------------add_ring---------------------------------------
338 // Supplied function returns the sum of the inputs. Guaranteed never
339 // to be passed a TOP or BOTTOM type, these are filtered out by
340 // pre-check.
341 const Type *AddINode::add_ring( const Type *t0, const Type *t1 ) const {
342 const TypeInt *r0 = t0->is_int(); // Handy access
343 const TypeInt *r1 = t1->is_int();
344 int lo = r0->_lo + r1->_lo;
345 int hi = r0->_hi + r1->_hi;
346 if( !(r0->is_con() && r1->is_con()) ) {
347 // Not both constants, compute approximate result
348 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
349 lo = min_jint; hi = max_jint; // Underflow on the low side
350 }
351 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
352 lo = min_jint; hi = max_jint; // Overflow on the high side
353 }
354 if( lo > hi ) { // Handle overflow
355 lo = min_jint; hi = max_jint;
356 }
357 } else {
358 // both constants, compute precise result using 'lo' and 'hi'
359 // Semantics define overflow and underflow for integer addition
360 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
361 }
362 return TypeInt::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
363 }
364
365
366 //=============================================================================
367 //------------------------------Idealize---------------------------------------
368 Node *AddLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
369 Node* in1 = in(1);
370 Node* in2 = in(2);
371 int op1 = in1->Opcode();
372 int op2 = in2->Opcode();
373 // Fold (con1-x)+con2 into (con1+con2)-x
374 if ( op1 == Op_AddL && op2 == Op_SubL ) {
375 // Swap edges to try optimizations below
376 in1 = in2;
377 in2 = in(1);
378 op1 = op2;
379 op2 = in2->Opcode();
380 }
381 // Fold (con1-x)+con2 into (con1+con2)-x
382 if( op1 == Op_SubL ) {
383 const Type *t_sub1 = phase->type( in1->in(1) );
384 const Type *t_2 = phase->type( in2 );
385 if( t_sub1->singleton() && t_2->singleton() && t_sub1 != Type::TOP && t_2 != Type::TOP )
386 return new (phase->C, 3) SubLNode(phase->makecon( add_ring( t_sub1, t_2 ) ),
387 in1->in(2) );
388 // Convert "(a-b)+(c-d)" into "(a+c)-(b+d)"
389 if( op2 == Op_SubL ) {
390 // Check for dead cycle: d = (a-b)+(c-d)
391 assert( in1->in(2) != this && in2->in(2) != this,
392 "dead loop in AddLNode::Ideal" );
393 Node *sub = new (phase->C, 3) SubLNode(NULL, NULL);
394 sub->init_req(1, phase->transform(new (phase->C, 3) AddLNode(in1->in(1), in2->in(1) ) ));
395 sub->init_req(2, phase->transform(new (phase->C, 3) AddLNode(in1->in(2), in2->in(2) ) ));
396 return sub;
397 }
398 // Convert "(a-b)+(b+c)" into "(a+c)"
399 if( op2 == Op_AddL && in1->in(2) == in2->in(1) ) {
400 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddLNode::Ideal");
401 return new (phase->C, 3) AddLNode(in1->in(1), in2->in(2));
402 }
403 // Convert "(a-b)+(c+b)" into "(a+c)"
404 if( op2 == Op_AddL && in1->in(2) == in2->in(2) ) {
405 assert(in1->in(1) != this && in2->in(1) != this,"dead loop in AddLNode::Ideal");
406 return new (phase->C, 3) AddLNode(in1->in(1), in2->in(1));
407 }
408 // Convert "(a-b)+(b-c)" into "(a-c)"
409 if( op2 == Op_SubL && in1->in(2) == in2->in(1) ) {
410 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddLNode::Ideal");
411 return new (phase->C, 3) SubLNode(in1->in(1), in2->in(2));
412 }
413 // Convert "(a-b)+(c-a)" into "(c-b)"
414 if( op2 == Op_SubL && in1->in(1) == in1->in(2) ) {
415 assert(in1->in(2) != this && in2->in(1) != this,"dead loop in AddLNode::Ideal");
416 return new (phase->C, 3) SubLNode(in2->in(1), in1->in(2));
417 }
418 }
419
420 // Convert "x+(0-y)" into "(x-y)"
421 if( op2 == Op_SubL && phase->type(in2->in(1)) == TypeLong::ZERO )
422 return new (phase->C, 3) SubLNode( in1, in2->in(2) );
423
424 // Convert "(0-y)+x" into "(x-y)"
425 if( op1 == Op_SubL && phase->type(in1->in(1)) == TypeInt::ZERO )
426 return new (phase->C, 3) SubLNode( in2, in1->in(2) );
427
428 // Convert "X+X+X+X+X...+X+Y" into "k*X+Y" or really convert "X+(X+Y)"
429 // into "(X<<1)+Y" and let shift-folding happen.
430 if( op2 == Op_AddL &&
431 in2->in(1) == in1 &&
432 op1 != Op_ConL &&
433 0 ) {
434 Node *shift = phase->transform(new (phase->C, 3) LShiftLNode(in1,phase->intcon(1)));
435 return new (phase->C, 3) AddLNode(shift,in2->in(2));
436 }
437
438 return AddNode::Ideal(phase, can_reshape);
439 }
440
441
442 //------------------------------Identity---------------------------------------
443 // Fold (x-y)+y OR y+(x-y) into x
444 Node *AddLNode::Identity( PhaseTransform *phase ) {
445 if( in(1)->Opcode() == Op_SubL && phase->eqv(in(1)->in(2),in(2)) ) {
446 return in(1)->in(1);
447 }
448 else if( in(2)->Opcode() == Op_SubL && phase->eqv(in(2)->in(2),in(1)) ) {
449 return in(2)->in(1);
450 }
451 return AddNode::Identity(phase);
452 }
453
454
455 //------------------------------add_ring---------------------------------------
456 // Supplied function returns the sum of the inputs. Guaranteed never
457 // to be passed a TOP or BOTTOM type, these are filtered out by
458 // pre-check.
459 const Type *AddLNode::add_ring( const Type *t0, const Type *t1 ) const {
460 const TypeLong *r0 = t0->is_long(); // Handy access
461 const TypeLong *r1 = t1->is_long();
462 jlong lo = r0->_lo + r1->_lo;
463 jlong hi = r0->_hi + r1->_hi;
464 if( !(r0->is_con() && r1->is_con()) ) {
465 // Not both constants, compute approximate result
466 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
467 lo =min_jlong; hi = max_jlong; // Underflow on the low side
468 }
469 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
470 lo = min_jlong; hi = max_jlong; // Overflow on the high side
471 }
472 if( lo > hi ) { // Handle overflow
473 lo = min_jlong; hi = max_jlong;
474 }
475 } else {
476 // both constants, compute precise result using 'lo' and 'hi'
477 // Semantics define overflow and underflow for integer addition
478 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
479 }
480 return TypeLong::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
481 }
482
483
484 //=============================================================================
485 //------------------------------add_of_identity--------------------------------
486 // Check for addition of the identity
487 const Type *AddFNode::add_of_identity( const Type *t1, const Type *t2 ) const {
488 // x ADD 0 should return x unless 'x' is a -zero
489 //
490 // const Type *zero = add_id(); // The additive identity
491 // jfloat f1 = t1->getf();
492 // jfloat f2 = t2->getf();
493 //
494 // if( t1->higher_equal( zero ) ) return t2;
495 // if( t2->higher_equal( zero ) ) return t1;
496
497 return NULL;
498 }
499
500 //------------------------------add_ring---------------------------------------
501 // Supplied function returns the sum of the inputs.
502 // This also type-checks the inputs for sanity. Guaranteed never to
503 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
504 const Type *AddFNode::add_ring( const Type *t0, const Type *t1 ) const {
505 // We must be adding 2 float constants.
506 return TypeF::make( t0->getf() + t1->getf() );
507 }
508
509 //------------------------------Ideal------------------------------------------
510 Node *AddFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
511 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
512 return AddNode::Ideal(phase, can_reshape); // commutative and associative transforms
513 }
514
515 // Floating point additions are not associative because of boundary conditions (infinity)
516 return commute(this,
517 phase->type( in(1) )->singleton(),
518 phase->type( in(2) )->singleton() ) ? this : NULL;
519 }
520
521
522 //=============================================================================
523 //------------------------------add_of_identity--------------------------------
524 // Check for addition of the identity
525 const Type *AddDNode::add_of_identity( const Type *t1, const Type *t2 ) const {
526 // x ADD 0 should return x unless 'x' is a -zero
527 //
528 // const Type *zero = add_id(); // The additive identity
529 // jfloat f1 = t1->getf();
530 // jfloat f2 = t2->getf();
531 //
532 // if( t1->higher_equal( zero ) ) return t2;
533 // if( t2->higher_equal( zero ) ) return t1;
534
535 return NULL;
536 }
537 //------------------------------add_ring---------------------------------------
538 // Supplied function returns the sum of the inputs.
539 // This also type-checks the inputs for sanity. Guaranteed never to
540 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
541 const Type *AddDNode::add_ring( const Type *t0, const Type *t1 ) const {
542 // We must be adding 2 double constants.
543 return TypeD::make( t0->getd() + t1->getd() );
544 }
545
546 //------------------------------Ideal------------------------------------------
547 Node *AddDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
548 if( IdealizedNumerics && !phase->C->method()->is_strict() ) {
549 return AddNode::Ideal(phase, can_reshape); // commutative and associative transforms
550 }
551
552 // Floating point additions are not associative because of boundary conditions (infinity)
553 return commute(this,
554 phase->type( in(1) )->singleton(),
555 phase->type( in(2) )->singleton() ) ? this : NULL;
556 }
557
558
559 //=============================================================================
560 //------------------------------Identity---------------------------------------
561 // If one input is a constant 0, return the other input.
562 Node *AddPNode::Identity( PhaseTransform *phase ) {
563 return ( phase->type( in(Offset) )->higher_equal( TypeX_ZERO ) ) ? in(Address) : this;
564 }
565
566 //------------------------------Idealize---------------------------------------
567 Node *AddPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
568 // Bail out if dead inputs
569 if( phase->type( in(Address) ) == Type::TOP ) return NULL;
570
571 // If the left input is an add of a constant, flatten the expression tree.
572 const Node *n = in(Address);
573 if (n->is_AddP() && n->in(Base) == in(Base)) {
574 const AddPNode *addp = n->as_AddP(); // Left input is an AddP
575 assert( !addp->in(Address)->is_AddP() ||
576 addp->in(Address)->as_AddP() != addp,
577 "dead loop in AddPNode::Ideal" );
578 // Type of left input's right input
579 const Type *t = phase->type( addp->in(Offset) );
580 if( t == Type::TOP ) return NULL;
581 const TypeX *t12 = t->is_intptr_t();
582 if( t12->is_con() ) { // Left input is an add of a constant?
583 // If the right input is a constant, combine constants
584 const Type *temp_t2 = phase->type( in(Offset) );
585 if( temp_t2 == Type::TOP ) return NULL;
586 const TypeX *t2 = temp_t2->is_intptr_t();
587 Node* address;
588 Node* offset;
589 if( t2->is_con() ) {
590 // The Add of the flattened expression
591 address = addp->in(Address);
592 offset = phase->MakeConX(t2->get_con() + t12->get_con());
593 } else {
594 // Else move the constant to the right. ((A+con)+B) into ((A+B)+con)
595 address = phase->transform(new (phase->C, 4) AddPNode(in(Base),addp->in(Address),in(Offset)));
596 offset = addp->in(Offset);
597 }
598 PhaseIterGVN *igvn = phase->is_IterGVN();
599 if( igvn ) {
600 set_req_X(Address,address,igvn);
601 set_req_X(Offset,offset,igvn);
602 } else {
603 set_req(Address,address);
604 set_req(Offset,offset);
605 }
606 return this;
607 }
608 }
609
610 // Raw pointers?
611 if( in(Base)->bottom_type() == Type::TOP ) {
612 // If this is a NULL+long form (from unsafe accesses), switch to a rawptr.
613 if (phase->type(in(Address)) == TypePtr::NULL_PTR) {
614 Node* offset = in(Offset);
615 return new (phase->C, 2) CastX2PNode(offset);
616 }
617 }
618
619 // If the right is an add of a constant, push the offset down.
620 // Convert: (ptr + (offset+con)) into (ptr+offset)+con.
621 // The idea is to merge array_base+scaled_index groups together,
622 // and only have different constant offsets from the same base.
623 const Node *add = in(Offset);
624 if( add->Opcode() == Op_AddX && add->in(1) != add ) {
625 const Type *t22 = phase->type( add->in(2) );
626 if( t22->singleton() && (t22 != Type::TOP) ) { // Right input is an add of a constant?
627 set_req(Address, phase->transform(new (phase->C, 4) AddPNode(in(Base),in(Address),add->in(1))));
628 set_req(Offset, add->in(2));
629 return this; // Made progress
630 }
631 }
632
633 return NULL; // No progress
634 }
635
636 //------------------------------bottom_type------------------------------------
637 // Bottom-type is the pointer-type with unknown offset.
638 const Type *AddPNode::bottom_type() const {
639 if (in(Address) == NULL) return TypePtr::BOTTOM;
640 const TypePtr *tp = in(Address)->bottom_type()->isa_ptr();
641 if( !tp ) return Type::TOP; // TOP input means TOP output
642 assert( in(Offset)->Opcode() != Op_ConP, "" );
643 const Type *t = in(Offset)->bottom_type();
644 if( t == Type::TOP )
645 return tp->add_offset(Type::OffsetTop);
646 const TypeX *tx = t->is_intptr_t();
647 intptr_t txoffset = Type::OffsetBot;
648 if (tx->is_con()) { // Left input is an add of a constant?
649 txoffset = tx->get_con();
650 }
651 return tp->add_offset(txoffset);
652 }
653
654 //------------------------------Value------------------------------------------
655 const Type *AddPNode::Value( PhaseTransform *phase ) const {
656 // Either input is TOP ==> the result is TOP
657 const Type *t1 = phase->type( in(Address) );
658 const Type *t2 = phase->type( in(Offset) );
659 if( t1 == Type::TOP ) return Type::TOP;
660 if( t2 == Type::TOP ) return Type::TOP;
661
662 // Left input is a pointer
663 const TypePtr *p1 = t1->isa_ptr();
664 // Right input is an int
665 const TypeX *p2 = t2->is_intptr_t();
666 // Add 'em
667 intptr_t p2offset = Type::OffsetBot;
668 if (p2->is_con()) { // Left input is an add of a constant?
669 p2offset = p2->get_con();
670 }
671 return p1->add_offset(p2offset);
672 }
673
674 //------------------------Ideal_base_and_offset--------------------------------
675 // Split an oop pointer into a base and offset.
676 // (The offset might be Type::OffsetBot in the case of an array.)
677 // Return the base, or NULL if failure.
678 Node* AddPNode::Ideal_base_and_offset(Node* ptr, PhaseTransform* phase,
679 // second return value:
680 intptr_t& offset) {
681 if (ptr->is_AddP()) {
682 Node* base = ptr->in(AddPNode::Base);
683 Node* addr = ptr->in(AddPNode::Address);
684 Node* offs = ptr->in(AddPNode::Offset);
685 if (base == addr || base->is_top()) {
686 offset = phase->find_intptr_t_con(offs, Type::OffsetBot);
687 if (offset != Type::OffsetBot) {
688 return addr;
689 }
690 }
691 }
692 offset = Type::OffsetBot;
693 return NULL;
694 }
695
696 //------------------------------unpack_offsets----------------------------------
697 // Collect the AddP offset values into the elements array, giving up
698 // if there are more than length.
699 int AddPNode::unpack_offsets(Node* elements[], int length) {
700 int count = 0;
701 Node* addr = this;
702 Node* base = addr->in(AddPNode::Base);
703 while (addr->is_AddP()) {
704 if (addr->in(AddPNode::Base) != base) {
705 // give up
706 return -1;
707 }
708 elements[count++] = addr->in(AddPNode::Offset);
709 if (count == length) {
710 // give up
711 return -1;
712 }
713 addr = addr->in(AddPNode::Address);
714 }
715 if (addr != base) {
716 return -1;
717 }
718 return count;
719 }
720
721 //------------------------------match_edge-------------------------------------
722 // Do we Match on this edge index or not? Do not match base pointer edge
723 uint AddPNode::match_edge(uint idx) const {
724 return idx > Base;
725 }
726
727 //=============================================================================
728 //------------------------------Identity---------------------------------------
729 Node *OrINode::Identity( PhaseTransform *phase ) {
730 // x | x => x
731 if (phase->eqv(in(1), in(2))) {
732 return in(1);
733 }
734
735 return AddNode::Identity(phase);
736 }
737
738 //------------------------------add_ring---------------------------------------
739 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
740 // the logical operations the ring's ADD is really a logical OR function.
741 // This also type-checks the inputs for sanity. Guaranteed never to
742 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
743 const Type *OrINode::add_ring( const Type *t0, const Type *t1 ) const {
744 const TypeInt *r0 = t0->is_int(); // Handy access
745 const TypeInt *r1 = t1->is_int();
746
747 // If both args are bool, can figure out better types
748 if ( r0 == TypeInt::BOOL ) {
749 if ( r1 == TypeInt::ONE) {
750 return TypeInt::ONE;
751 } else if ( r1 == TypeInt::BOOL ) {
752 return TypeInt::BOOL;
753 }
754 } else if ( r0 == TypeInt::ONE ) {
755 if ( r1 == TypeInt::BOOL ) {
756 return TypeInt::ONE;
757 }
758 }
759
760 // If either input is not a constant, just return all integers.
761 if( !r0->is_con() || !r1->is_con() )
762 return TypeInt::INT; // Any integer, but still no symbols.
763
764 // Otherwise just OR them bits.
765 return TypeInt::make( r0->get_con() | r1->get_con() );
766 }
767
768 //=============================================================================
769 //------------------------------Identity---------------------------------------
770 Node *OrLNode::Identity( PhaseTransform *phase ) {
771 // x | x => x
772 if (phase->eqv(in(1), in(2))) {
773 return in(1);
774 }
775
776 return AddNode::Identity(phase);
777 }
778
779 //------------------------------add_ring---------------------------------------
780 const Type *OrLNode::add_ring( const Type *t0, const Type *t1 ) const {
781 const TypeLong *r0 = t0->is_long(); // Handy access
782 const TypeLong *r1 = t1->is_long();
783
784 // If either input is not a constant, just return all integers.
785 if( !r0->is_con() || !r1->is_con() )
786 return TypeLong::LONG; // Any integer, but still no symbols.
787
788 // Otherwise just OR them bits.
789 return TypeLong::make( r0->get_con() | r1->get_con() );
790 }
791
792 //=============================================================================
793 //------------------------------add_ring---------------------------------------
794 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
795 // the logical operations the ring's ADD is really a logical OR function.
796 // This also type-checks the inputs for sanity. Guaranteed never to
797 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
798 const Type *XorINode::add_ring( const Type *t0, const Type *t1 ) const {
799 const TypeInt *r0 = t0->is_int(); // Handy access
800 const TypeInt *r1 = t1->is_int();
801
802 // Complementing a boolean?
803 if( r0 == TypeInt::BOOL && ( r1 == TypeInt::ONE
804 || r1 == TypeInt::BOOL))
805 return TypeInt::BOOL;
806
807 if( !r0->is_con() || !r1->is_con() ) // Not constants
808 return TypeInt::INT; // Any integer, but still no symbols.
809
810 // Otherwise just XOR them bits.
811 return TypeInt::make( r0->get_con() ^ r1->get_con() );
812 }
813
814 //=============================================================================
815 //------------------------------add_ring---------------------------------------
816 const Type *XorLNode::add_ring( const Type *t0, const Type *t1 ) const {
817 const TypeLong *r0 = t0->is_long(); // Handy access
818 const TypeLong *r1 = t1->is_long();
819
820 // If either input is not a constant, just return all integers.
821 if( !r0->is_con() || !r1->is_con() )
822 return TypeLong::LONG; // Any integer, but still no symbols.
823
824 // Otherwise just OR them bits.
825 return TypeLong::make( r0->get_con() ^ r1->get_con() );
826 }
827
828 //=============================================================================
829 //------------------------------add_ring---------------------------------------
830 // Supplied function returns the sum of the inputs.
831 const Type *MaxINode::add_ring( const Type *t0, const Type *t1 ) const {
832 const TypeInt *r0 = t0->is_int(); // Handy access
833 const TypeInt *r1 = t1->is_int();
834
835 // Otherwise just MAX them bits.
836 return TypeInt::make( MAX2(r0->_lo,r1->_lo), MAX2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
837 }
838
839 //=============================================================================
840 //------------------------------Idealize---------------------------------------
841 // MINs show up in range-check loop limit calculations. Look for
842 // "MIN2(x+c0,MIN2(y,x+c1))". Pick the smaller constant: "MIN2(x+c0,y)"
843 Node *MinINode::Ideal(PhaseGVN *phase, bool can_reshape) {
844 Node *progress = NULL;
845 // Force a right-spline graph
846 Node *l = in(1);
847 Node *r = in(2);
848 // Transform MinI1( MinI2(a,b), c) into MinI1( a, MinI2(b,c) )
849 // to force a right-spline graph for the rest of MinINode::Ideal().
850 if( l->Opcode() == Op_MinI ) {
851 assert( l != l->in(1), "dead loop in MinINode::Ideal" );
852 r = phase->transform(new (phase->C, 3) MinINode(l->in(2),r));
853 l = l->in(1);
854 set_req(1, l);
855 set_req(2, r);
856 return this;
857 }
858
859 // Get left input & constant
860 Node *x = l;
861 int x_off = 0;
862 if( x->Opcode() == Op_AddI && // Check for "x+c0" and collect constant
863 x->in(2)->is_Con() ) {
864 const Type *t = x->in(2)->bottom_type();
865 if( t == Type::TOP ) return NULL; // No progress
866 x_off = t->is_int()->get_con();
867 x = x->in(1);
868 }
869
870 // Scan a right-spline-tree for MINs
871 Node *y = r;
872 int y_off = 0;
873 // Check final part of MIN tree
874 if( y->Opcode() == Op_AddI && // Check for "y+c1" and collect constant
875 y->in(2)->is_Con() ) {
876 const Type *t = y->in(2)->bottom_type();
877 if( t == Type::TOP ) return NULL; // No progress
878 y_off = t->is_int()->get_con();
879 y = y->in(1);
880 }
881 if( x->_idx > y->_idx && r->Opcode() != Op_MinI ) {
882 swap_edges(1, 2);
883 return this;
884 }
885
886
887 if( r->Opcode() == Op_MinI ) {
888 assert( r != r->in(2), "dead loop in MinINode::Ideal" );
889 y = r->in(1);
890 // Check final part of MIN tree
891 if( y->Opcode() == Op_AddI &&// Check for "y+c1" and collect constant
892 y->in(2)->is_Con() ) {
893 const Type *t = y->in(2)->bottom_type();
894 if( t == Type::TOP ) return NULL; // No progress
895 y_off = t->is_int()->get_con();
896 y = y->in(1);
897 }
898
899 if( x->_idx > y->_idx )
900 return new (phase->C, 3) MinINode(r->in(1),phase->transform(new (phase->C, 3) MinINode(l,r->in(2))));
901
902 // See if covers: MIN2(x+c0,MIN2(y+c1,z))
903 if( !phase->eqv(x,y) ) return NULL;
904 // If (y == x) transform MIN2(x+c0, MIN2(x+c1,z)) into
905 // MIN2(x+c0 or x+c1 which less, z).
906 return new (phase->C, 3) MinINode(phase->transform(new (phase->C, 3) AddINode(x,phase->intcon(MIN2(x_off,y_off)))),r->in(2));
907 } else {
908 // See if covers: MIN2(x+c0,y+c1)
909 if( !phase->eqv(x,y) ) return NULL;
910 // If (y == x) transform MIN2(x+c0,x+c1) into x+c0 or x+c1 which less.
911 return new (phase->C, 3) AddINode(x,phase->intcon(MIN2(x_off,y_off)));
912 }
913
914 }
915
916 //------------------------------add_ring---------------------------------------
917 // Supplied function returns the sum of the inputs.
918 const Type *MinINode::add_ring( const Type *t0, const Type *t1 ) const {
919 const TypeInt *r0 = t0->is_int(); // Handy access
920 const TypeInt *r1 = t1->is_int();
921
922 // Otherwise just MIN them bits.
923 return TypeInt::make( MIN2(r0->_lo,r1->_lo), MIN2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
924 }