1 /*
2 * Copyright (c) 1997, 2022, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
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23 */
24
25 #include "precompiled.hpp"
26 #include "memory/allocation.inline.hpp"
27 #include "opto/addnode.hpp"
28 #include "opto/castnode.hpp"
29 #include "opto/cfgnode.hpp"
30 #include "opto/connode.hpp"
31 #include "opto/machnode.hpp"
32 #include "opto/movenode.hpp"
33 #include "opto/mulnode.hpp"
34 #include "opto/phaseX.hpp"
35 #include "opto/subnode.hpp"
36
37 // Portions of code courtesy of Clifford Click
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(PhaseGVN* 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(PhaseGVN* phase, Node* add) {
66 Node *in1 = add->in(1);
67 Node *in2 = add->in(2);
68
69 // convert "max(a,b) + min(a,b)" into "a+b".
70 if ((in1->Opcode() == add->as_Add()->max_opcode() && in2->Opcode() == add->as_Add()->min_opcode())
71 || (in1->Opcode() == add->as_Add()->min_opcode() && in2->Opcode() == add->as_Add()->max_opcode())) {
72 Node *in11 = in1->in(1);
73 Node *in12 = in1->in(2);
74
75 Node *in21 = in2->in(1);
76 Node *in22 = in2->in(2);
77
78 if ((in11 == in21 && in12 == in22) ||
79 (in11 == in22 && in12 == in21)) {
80 add->set_req_X(1, in11, phase);
81 add->set_req_X(2, in12, phase);
82 return true;
83 }
84 }
85
86 bool con_left = phase->type(in1)->singleton();
87 bool con_right = phase->type(in2)->singleton();
88
89 // Convert "1+x" into "x+1".
90 // Right is a constant; leave it
91 if( con_right ) return false;
92 // Left is a constant; move it right.
93 if( con_left ) {
94 add->swap_edges(1, 2);
95 return true;
96 }
97
98 // Convert "Load+x" into "x+Load".
99 // Now check for loads
100 if (in2->is_Load()) {
101 if (!in1->is_Load()) {
102 // already x+Load to return
103 return false;
104 }
105 // both are loads, so fall through to sort inputs by idx
106 } else if( in1->is_Load() ) {
107 // Left is a Load and Right is not; move it right.
108 add->swap_edges(1, 2);
109 return true;
110 }
111
112 PhiNode *phi;
113 // Check for tight loop increments: Loop-phi of Add of loop-phi
114 if (in1->is_Phi() && (phi = in1->as_Phi()) && phi->region()->is_Loop() && phi->in(2) == add)
115 return false;
116 if (in2->is_Phi() && (phi = in2->as_Phi()) && phi->region()->is_Loop() && phi->in(2) == add) {
117 add->swap_edges(1, 2);
118 return true;
119 }
120
121 // Otherwise, sort inputs (commutativity) to help value numbering.
122 if( in1->_idx > in2->_idx ) {
123 add->swap_edges(1, 2);
124 return true;
125 }
126 return false;
127 }
128
129 //------------------------------Idealize---------------------------------------
130 // If we get here, we assume we are associative!
131 Node *AddNode::Ideal(PhaseGVN *phase, bool can_reshape) {
132 const Type *t1 = phase->type(in(1));
133 const Type *t2 = phase->type(in(2));
134 bool con_left = t1->singleton();
135 bool con_right = t2->singleton();
136
137 // Check for commutative operation desired
138 if (commute(phase, this)) return this;
139
140 AddNode *progress = NULL; // Progress flag
141
142 // Convert "(x+1)+2" into "x+(1+2)". If the right input is a
143 // constant, and the left input is an add of a constant, flatten the
144 // expression tree.
145 Node *add1 = in(1);
146 Node *add2 = in(2);
147 int add1_op = add1->Opcode();
148 int this_op = Opcode();
149 if (con_right && t2 != Type::TOP && // Right input is a constant?
150 add1_op == this_op) { // Left input is an Add?
151
152 // Type of left _in right input
153 const Type *t12 = phase->type(add1->in(2));
154 if (t12->singleton() && t12 != Type::TOP) { // Left input is an add of a constant?
155 // Check for rare case of closed data cycle which can happen inside
156 // unreachable loops. In these cases the computation is undefined.
157 #ifdef ASSERT
158 Node *add11 = add1->in(1);
159 int add11_op = add11->Opcode();
160 if ((add1 == add1->in(1))
161 || (add11_op == this_op && add11->in(1) == add1)) {
162 assert(false, "dead loop in AddNode::Ideal");
163 }
164 #endif
165 // The Add of the flattened expression
166 Node *x1 = add1->in(1);
167 Node *x2 = phase->makecon(add1->as_Add()->add_ring(t2, t12));
168 set_req_X(2, x2, phase);
169 set_req_X(1, x1, phase);
170 progress = this; // Made progress
171 add1 = in(1);
172 add1_op = add1->Opcode();
173 }
174 }
175
176 // Convert "(x+1)+y" into "(x+y)+1". Push constants down the expression tree.
177 if (add1_op == this_op && !con_right) {
178 Node *a12 = add1->in(2);
179 const Type *t12 = phase->type( a12 );
180 if (t12->singleton() && t12 != Type::TOP && (add1 != add1->in(1)) &&
181 !(add1->in(1)->is_Phi() && (add1->in(1)->as_Phi()->is_tripcount(T_INT) || add1->in(1)->as_Phi()->is_tripcount(T_LONG)))) {
182 assert(add1->in(1) != this, "dead loop in AddNode::Ideal");
183 add2 = add1->clone();
184 add2->set_req(2, in(2));
185 add2 = phase->transform(add2);
186 set_req_X(1, add2, phase);
187 set_req_X(2, a12, phase);
188 progress = this;
189 add2 = a12;
190 }
191 }
192
193 // Convert "x+(y+1)" into "(x+y)+1". Push constants down the expression tree.
194 int add2_op = add2->Opcode();
195 if (add2_op == this_op && !con_left) {
196 Node *a22 = add2->in(2);
197 const Type *t22 = phase->type( a22 );
198 if (t22->singleton() && t22 != Type::TOP && (add2 != add2->in(1)) &&
199 !(add2->in(1)->is_Phi() && (add2->in(1)->as_Phi()->is_tripcount(T_INT) || add2->in(1)->as_Phi()->is_tripcount(T_LONG)))) {
200 assert(add2->in(1) != this, "dead loop in AddNode::Ideal");
201 Node *addx = add2->clone();
202 addx->set_req(1, in(1));
203 addx->set_req(2, add2->in(1));
204 addx = phase->transform(addx);
205 set_req_X(1, addx, phase);
206 set_req_X(2, a22, phase);
207 progress = this;
208 }
209 }
210
211 return progress;
212 }
213
214 //------------------------------Value-----------------------------------------
215 // An add node sums it's two _in. If one input is an RSD, we must mixin
216 // the other input's symbols.
217 const Type* AddNode::Value(PhaseGVN* phase) const {
218 // Either input is TOP ==> the result is TOP
219 const Type *t1 = phase->type( in(1) );
220 const Type *t2 = phase->type( in(2) );
221 if( t1 == Type::TOP ) return Type::TOP;
222 if( t2 == Type::TOP ) return Type::TOP;
223
224 // Either input is BOTTOM ==> the result is the local BOTTOM
225 const Type *bot = bottom_type();
226 if( (t1 == bot) || (t2 == bot) ||
227 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
228 return bot;
229
230 // Check for an addition involving the additive identity
231 const Type *tadd = add_of_identity( t1, t2 );
232 if( tadd ) return tadd;
233
234 return add_ring(t1,t2); // Local flavor of type addition
235 }
236
237 //------------------------------add_identity-----------------------------------
238 // Check for addition of the identity
239 const Type *AddNode::add_of_identity( const Type *t1, const Type *t2 ) const {
240 const Type *zero = add_id(); // The additive identity
241 if( t1->higher_equal( zero ) ) return t2;
242 if( t2->higher_equal( zero ) ) return t1;
243
244 return NULL;
245 }
246
247 AddNode* AddNode::make(Node* in1, Node* in2, BasicType bt) {
248 switch (bt) {
249 case T_INT:
250 return new AddINode(in1, in2);
251 case T_LONG:
252 return new AddLNode(in1, in2);
253 default:
254 fatal("Not implemented for %s", type2name(bt));
255 }
256 return NULL;
257 }
258
259 //=============================================================================
260 //------------------------------Idealize---------------------------------------
261 Node* AddNode::IdealIL(PhaseGVN* phase, bool can_reshape, BasicType bt) {
262 Node* in1 = in(1);
263 Node* in2 = in(2);
264 int op1 = in1->Opcode();
265 int op2 = in2->Opcode();
266 // Fold (con1-x)+con2 into (con1+con2)-x
267 if (op1 == Op_Add(bt) && op2 == Op_Sub(bt)) {
268 // Swap edges to try optimizations below
269 in1 = in2;
270 in2 = in(1);
271 op1 = op2;
272 op2 = in2->Opcode();
273 }
274 if (op1 == Op_Sub(bt)) {
275 const Type* t_sub1 = phase->type(in1->in(1));
276 const Type* t_2 = phase->type(in2 );
277 if (t_sub1->singleton() && t_2->singleton() && t_sub1 != Type::TOP && t_2 != Type::TOP) {
278 return SubNode::make(phase->makecon(add_ring(t_sub1, t_2)), in1->in(2), bt);
279 }
280 // Convert "(a-b)+(c-d)" into "(a+c)-(b+d)"
281 if (op2 == Op_Sub(bt)) {
282 // Check for dead cycle: d = (a-b)+(c-d)
283 assert( in1->in(2) != this && in2->in(2) != this,
284 "dead loop in AddINode::Ideal" );
285 Node* sub = SubNode::make(NULL, NULL, bt);
286 sub->init_req(1, phase->transform(AddNode::make(in1->in(1), in2->in(1), bt)));
287 sub->init_req(2, phase->transform(AddNode::make(in1->in(2), in2->in(2), bt)));
288 return sub;
289 }
290 // Convert "(a-b)+(b+c)" into "(a+c)"
291 if (op2 == Op_Add(bt) && in1->in(2) == in2->in(1)) {
292 assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddINode::Ideal/AddLNode::Ideal");
293 return AddNode::make(in1->in(1), in2->in(2), bt);
294 }
295 // Convert "(a-b)+(c+b)" into "(a+c)"
296 if (op2 == Op_Add(bt) && in1->in(2) == in2->in(2)) {
297 assert(in1->in(1) != this && in2->in(1) != this,"dead loop in AddINode::Ideal/AddLNode::Ideal");
298 return AddNode::make(in1->in(1), in2->in(1), bt);
299 }
300 }
301
302 // Convert (con - y) + x into "(x - y) + con"
303 if (op1 == Op_Sub(bt) && in1->in(1)->Opcode() == Op_ConIL(bt)
304 && in1 != in1->in(2) && !(in1->in(2)->is_Phi() && in1->in(2)->as_Phi()->is_tripcount(bt))) {
305 return AddNode::make(phase->transform(SubNode::make(in2, in1->in(2), bt)), in1->in(1), bt);
306 }
307
308 // Convert x + (con - y) into "(x - y) + con"
309 if (op2 == Op_Sub(bt) && in2->in(1)->Opcode() == Op_ConIL(bt)
310 && in2 != in2->in(2) && !(in2->in(2)->is_Phi() && in2->in(2)->as_Phi()->is_tripcount(bt))) {
311 return AddNode::make(phase->transform(SubNode::make(in1, in2->in(2), bt)), in2->in(1), bt);
312 }
313
314 // Associative
315 if (op1 == Op_Mul(bt) && op2 == Op_Mul(bt)) {
316 Node* add_in1 = NULL;
317 Node* add_in2 = NULL;
318 Node* mul_in = NULL;
319
320 if (in1->in(1) == in2->in(1)) {
321 // Convert "a*b+a*c into a*(b+c)
322 add_in1 = in1->in(2);
323 add_in2 = in2->in(2);
324 mul_in = in1->in(1);
325 } else if (in1->in(2) == in2->in(1)) {
326 // Convert a*b+b*c into b*(a+c)
327 add_in1 = in1->in(1);
328 add_in2 = in2->in(2);
329 mul_in = in1->in(2);
330 } else if (in1->in(2) == in2->in(2)) {
331 // Convert a*c+b*c into (a+b)*c
332 add_in1 = in1->in(1);
333 add_in2 = in2->in(1);
334 mul_in = in1->in(2);
335 } else if (in1->in(1) == in2->in(2)) {
336 // Convert a*b+c*a into a*(b+c)
337 add_in1 = in1->in(2);
338 add_in2 = in2->in(1);
339 mul_in = in1->in(1);
340 }
341
342 if (mul_in != NULL) {
343 Node* add = phase->transform(AddNode::make(add_in1, add_in2, bt));
344 return MulNode::make(mul_in, add, bt);
345 }
346 }
347
348 // Convert (x >>> rshift) + (x << lshift) into RotateRight(x, rshift)
349 if (Matcher::match_rule_supported(Op_RotateRight) &&
350 ((op1 == Op_URShift(bt) && op2 == Op_LShift(bt)) || (op1 == Op_LShift(bt) && op2 == Op_URShift(bt))) &&
351 in1->in(1) != NULL && in1->in(1) == in2->in(1)) {
352 Node* rshift = op1 == Op_URShift(bt) ? in1->in(2) : in2->in(2);
353 Node* lshift = op1 == Op_URShift(bt) ? in2->in(2) : in1->in(2);
354 if (rshift != NULL && lshift != NULL) {
355 const TypeInt* rshift_t = phase->type(rshift)->isa_int();
356 const TypeInt* lshift_t = phase->type(lshift)->isa_int();
357 int bits = bt == T_INT ? 32 : 64;
358 int mask = bt == T_INT ? 0x1F : 0x3F;
359 if (lshift_t != NULL && lshift_t->is_con() &&
360 rshift_t != NULL && rshift_t->is_con() &&
361 ((lshift_t->get_con() & mask) == (bits - (rshift_t->get_con() & mask)))) {
362 return new RotateRightNode(in1->in(1), phase->intcon(rshift_t->get_con() & mask), TypeInteger::bottom(bt));
363 }
364 }
365 }
366
367 return AddNode::Ideal(phase, can_reshape);
368 }
369
370
371 Node* AddINode::Ideal(PhaseGVN* phase, bool can_reshape) {
372 Node* in1 = in(1);
373 Node* in2 = in(2);
374 int op1 = in1->Opcode();
375 int op2 = in2->Opcode();
376
377 // Convert (x>>>z)+y into (x+(y<<z))>>>z for small constant z and y.
378 // Helps with array allocation math constant folding
379 // See 4790063:
380 // Unrestricted transformation is unsafe for some runtime values of 'x'
381 // ( x == 0, z == 1, y == -1 ) fails
382 // ( x == -5, z == 1, y == 1 ) fails
383 // Transform works for small z and small negative y when the addition
384 // (x + (y << z)) does not cross zero.
385 // Implement support for negative y and (x >= -(y << z))
386 // Have not observed cases where type information exists to support
387 // positive y and (x <= -(y << z))
388 if (op1 == Op_URShiftI && op2 == Op_ConI &&
389 in1->in(2)->Opcode() == Op_ConI) {
390 jint z = phase->type(in1->in(2))->is_int()->get_con() & 0x1f; // only least significant 5 bits matter
391 jint y = phase->type(in2)->is_int()->get_con();
392
393 if (z < 5 && -5 < y && y < 0) {
394 const Type* t_in11 = phase->type(in1->in(1));
395 if( t_in11 != Type::TOP && (t_in11->is_int()->_lo >= -(y << z))) {
396 Node* a = phase->transform(new AddINode( in1->in(1), phase->intcon(y<<z)));
397 return new URShiftINode(a, in1->in(2));
398 }
399 }
400 }
401
402 return AddNode::IdealIL(phase, can_reshape, T_INT);
403 }
404
405
406 //------------------------------Identity---------------------------------------
407 // Fold (x-y)+y OR y+(x-y) into x
408 Node* AddINode::Identity(PhaseGVN* phase) {
409 if (in(1)->Opcode() == Op_SubI && in(1)->in(2) == in(2)) {
410 return in(1)->in(1);
411 } else if (in(2)->Opcode() == Op_SubI && in(2)->in(2) == in(1)) {
412 return in(2)->in(1);
413 }
414 return AddNode::Identity(phase);
415 }
416
417
418 //------------------------------add_ring---------------------------------------
419 // Supplied function returns the sum of the inputs. Guaranteed never
420 // to be passed a TOP or BOTTOM type, these are filtered out by
421 // pre-check.
422 const Type *AddINode::add_ring( const Type *t0, const Type *t1 ) const {
423 const TypeInt *r0 = t0->is_int(); // Handy access
424 const TypeInt *r1 = t1->is_int();
425 int lo = java_add(r0->_lo, r1->_lo);
426 int hi = java_add(r0->_hi, r1->_hi);
427 if( !(r0->is_con() && r1->is_con()) ) {
428 // Not both constants, compute approximate result
429 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
430 lo = min_jint; hi = max_jint; // Underflow on the low side
431 }
432 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
433 lo = min_jint; hi = max_jint; // Overflow on the high side
434 }
435 if( lo > hi ) { // Handle overflow
436 lo = min_jint; hi = max_jint;
437 }
438 } else {
439 // both constants, compute precise result using 'lo' and 'hi'
440 // Semantics define overflow and underflow for integer addition
441 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
442 }
443 return TypeInt::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
444 }
445
446
447 //=============================================================================
448 //------------------------------Idealize---------------------------------------
449 Node* AddLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
450 return AddNode::IdealIL(phase, can_reshape, T_LONG);
451 }
452
453
454 //------------------------------Identity---------------------------------------
455 // Fold (x-y)+y OR y+(x-y) into x
456 Node* AddLNode::Identity(PhaseGVN* phase) {
457 if (in(1)->Opcode() == Op_SubL && in(1)->in(2) == in(2)) {
458 return in(1)->in(1);
459 } else if (in(2)->Opcode() == Op_SubL && in(2)->in(2) == in(1)) {
460 return in(2)->in(1);
461 }
462 return AddNode::Identity(phase);
463 }
464
465
466 //------------------------------add_ring---------------------------------------
467 // Supplied function returns the sum of the inputs. Guaranteed never
468 // to be passed a TOP or BOTTOM type, these are filtered out by
469 // pre-check.
470 const Type *AddLNode::add_ring( const Type *t0, const Type *t1 ) const {
471 const TypeLong *r0 = t0->is_long(); // Handy access
472 const TypeLong *r1 = t1->is_long();
473 jlong lo = java_add(r0->_lo, r1->_lo);
474 jlong hi = java_add(r0->_hi, r1->_hi);
475 if( !(r0->is_con() && r1->is_con()) ) {
476 // Not both constants, compute approximate result
477 if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
478 lo =min_jlong; hi = max_jlong; // Underflow on the low side
479 }
480 if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
481 lo = min_jlong; hi = max_jlong; // Overflow on the high side
482 }
483 if( lo > hi ) { // Handle overflow
484 lo = min_jlong; hi = max_jlong;
485 }
486 } else {
487 // both constants, compute precise result using 'lo' and 'hi'
488 // Semantics define overflow and underflow for integer addition
489 // as expected. In particular: 0x80000000 + 0x80000000 --> 0x0
490 }
491 return TypeLong::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
492 }
493
494
495 //=============================================================================
496 //------------------------------add_of_identity--------------------------------
497 // Check for addition of the identity
498 const Type *AddFNode::add_of_identity( const Type *t1, const Type *t2 ) const {
499 // x ADD 0 should return x unless 'x' is a -zero
500 //
501 // const Type *zero = add_id(); // The additive identity
502 // jfloat f1 = t1->getf();
503 // jfloat f2 = t2->getf();
504 //
505 // if( t1->higher_equal( zero ) ) return t2;
506 // if( t2->higher_equal( zero ) ) return t1;
507
508 return NULL;
509 }
510
511 //------------------------------add_ring---------------------------------------
512 // Supplied function returns the sum of the inputs.
513 // This also type-checks the inputs for sanity. Guaranteed never to
514 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
515 const Type *AddFNode::add_ring( const Type *t0, const Type *t1 ) const {
516 // We must be adding 2 float constants.
517 return TypeF::make( t0->getf() + t1->getf() );
518 }
519
520 //------------------------------Ideal------------------------------------------
521 Node *AddFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
522 // Floating point additions are not associative because of boundary conditions (infinity)
523 return commute(phase, this) ? this : NULL;
524 }
525
526
527 //=============================================================================
528 //------------------------------add_of_identity--------------------------------
529 // Check for addition of the identity
530 const Type *AddDNode::add_of_identity( const Type *t1, const Type *t2 ) const {
531 // x ADD 0 should return x unless 'x' is a -zero
532 //
533 // const Type *zero = add_id(); // The additive identity
534 // jfloat f1 = t1->getf();
535 // jfloat f2 = t2->getf();
536 //
537 // if( t1->higher_equal( zero ) ) return t2;
538 // if( t2->higher_equal( zero ) ) return t1;
539
540 return NULL;
541 }
542 //------------------------------add_ring---------------------------------------
543 // Supplied function returns the sum of the inputs.
544 // This also type-checks the inputs for sanity. Guaranteed never to
545 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
546 const Type *AddDNode::add_ring( const Type *t0, const Type *t1 ) const {
547 // We must be adding 2 double constants.
548 return TypeD::make( t0->getd() + t1->getd() );
549 }
550
551 //------------------------------Ideal------------------------------------------
552 Node *AddDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
553 // Floating point additions are not associative because of boundary conditions (infinity)
554 return commute(phase, this) ? this : NULL;
555 }
556
557
558 //=============================================================================
559 //------------------------------Identity---------------------------------------
560 // If one input is a constant 0, return the other input.
561 Node* AddPNode::Identity(PhaseGVN* phase) {
562 return ( phase->type( in(Offset) )->higher_equal( TypeX_ZERO ) ) ? in(Address) : this;
563 }
564
565 //------------------------------Idealize---------------------------------------
566 Node *AddPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
567 // Bail out if dead inputs
568 if( phase->type( in(Address) ) == Type::TOP ) return NULL;
569
570 // If the left input is an add of a constant, flatten the expression tree.
571 const Node *n = in(Address);
572 if (n->is_AddP() && n->in(Base) == in(Base)) {
573 const AddPNode *addp = n->as_AddP(); // Left input is an AddP
574 assert( !addp->in(Address)->is_AddP() ||
575 addp->in(Address)->as_AddP() != addp,
576 "dead loop in AddPNode::Ideal" );
577 // Type of left input's right input
578 const Type *t = phase->type( addp->in(Offset) );
579 if( t == Type::TOP ) return NULL;
580 const TypeX *t12 = t->is_intptr_t();
581 if( t12->is_con() ) { // Left input is an add of a constant?
582 // If the right input is a constant, combine constants
583 const Type *temp_t2 = phase->type( in(Offset) );
584 if( temp_t2 == Type::TOP ) return NULL;
585 const TypeX *t2 = temp_t2->is_intptr_t();
586 Node* address;
587 Node* offset;
588 if( t2->is_con() ) {
589 // The Add of the flattened expression
590 address = addp->in(Address);
591 offset = phase->MakeConX(t2->get_con() + t12->get_con());
592 } else {
593 // Else move the constant to the right. ((A+con)+B) into ((A+B)+con)
594 address = phase->transform(new AddPNode(in(Base),addp->in(Address),in(Offset)));
595 offset = addp->in(Offset);
596 }
597 set_req_X(Address, address, phase);
598 set_req_X(Offset, offset, phase);
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 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 AddPNode(in(Base),in(Address),add->in(1))));
621 set_req_X(Offset, add->in(2), phase); // puts add on igvn worklist if needed
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 if (tp->isa_aryptr()) {
645 // In the case of a flattened inline type array, each field has its
646 // own slice so we need to extract the field being accessed from
647 // the address computation
648 return tp->is_aryptr()->add_field_offset_and_offset(txoffset);
649 }
650 return tp->add_offset(txoffset);
651 }
652
653 //------------------------------Value------------------------------------------
654 const Type* AddPNode::Value(PhaseGVN* phase) const {
655 // Either input is TOP ==> the result is TOP
656 const Type *t1 = phase->type( in(Address) );
657 const Type *t2 = phase->type( in(Offset) );
658 if( t1 == Type::TOP ) return Type::TOP;
659 if( t2 == Type::TOP ) return Type::TOP;
660
661 // Left input is a pointer
662 const TypePtr *p1 = t1->isa_ptr();
663 // Right input is an int
664 const TypeX *p2 = t2->is_intptr_t();
665 // Add 'em
666 intptr_t p2offset = Type::OffsetBot;
667 if (p2->is_con()) { // Left input is an add of a constant?
668 p2offset = p2->get_con();
669 }
670 if (p1->isa_aryptr()) {
671 // In the case of a flattened inline type array, each field has its
672 // own slice so we need to extract the field being accessed from
673 // the address computation
674 return p1->is_aryptr()->add_field_offset_and_offset(p2offset);
675 }
676 return p1->add_offset(p2offset);
677 }
678
679 //------------------------Ideal_base_and_offset--------------------------------
680 // Split an oop pointer into a base and offset.
681 // (The offset might be Type::OffsetBot in the case of an array.)
682 // Return the base, or NULL if failure.
683 Node* AddPNode::Ideal_base_and_offset(Node* ptr, PhaseTransform* phase,
684 // second return value:
685 intptr_t& offset) {
686 if (ptr->is_AddP()) {
687 Node* base = ptr->in(AddPNode::Base);
688 Node* addr = ptr->in(AddPNode::Address);
689 Node* offs = ptr->in(AddPNode::Offset);
690 if (base == addr || base->is_top()) {
691 offset = phase->find_intptr_t_con(offs, Type::OffsetBot);
692 if (offset != Type::OffsetBot) {
693 return addr;
694 }
695 }
696 }
697 offset = Type::OffsetBot;
698 return NULL;
699 }
700
701 //------------------------------unpack_offsets----------------------------------
702 // Collect the AddP offset values into the elements array, giving up
703 // if there are more than length.
704 int AddPNode::unpack_offsets(Node* elements[], int length) {
705 int count = 0;
706 Node* addr = this;
707 Node* base = addr->in(AddPNode::Base);
708 while (addr->is_AddP()) {
709 if (addr->in(AddPNode::Base) != base) {
710 // give up
711 return -1;
712 }
713 elements[count++] = addr->in(AddPNode::Offset);
714 if (count == length) {
715 // give up
716 return -1;
717 }
718 addr = addr->in(AddPNode::Address);
719 }
720 if (addr != base) {
721 return -1;
722 }
723 return count;
724 }
725
726 //------------------------------match_edge-------------------------------------
727 // Do we Match on this edge index or not? Do not match base pointer edge
728 uint AddPNode::match_edge(uint idx) const {
729 return idx > Base;
730 }
731
732 //=============================================================================
733 //------------------------------Identity---------------------------------------
734 Node* OrINode::Identity(PhaseGVN* phase) {
735 // x | x => x
736 if (in(1) == in(2)) {
737 return in(1);
738 }
739
740 return AddNode::Identity(phase);
741 }
742
743 // Find shift value for Integer or Long OR.
744 Node* rotate_shift(PhaseGVN* phase, Node* lshift, Node* rshift, int mask) {
745 // val << norm_con_shift | val >> ({32|64} - norm_con_shift) => rotate_left val, norm_con_shift
746 const TypeInt* lshift_t = phase->type(lshift)->isa_int();
747 const TypeInt* rshift_t = phase->type(rshift)->isa_int();
748 if (lshift_t != NULL && lshift_t->is_con() &&
749 rshift_t != NULL && rshift_t->is_con() &&
750 ((lshift_t->get_con() & mask) == ((mask + 1) - (rshift_t->get_con() & mask)))) {
751 return phase->intcon(lshift_t->get_con() & mask);
752 }
753 // val << var_shift | val >> ({0|32|64} - var_shift) => rotate_left val, var_shift
754 if (rshift->Opcode() == Op_SubI && rshift->in(2) == lshift && rshift->in(1)->is_Con()){
755 const TypeInt* shift_t = phase->type(rshift->in(1))->isa_int();
756 if (shift_t != NULL && shift_t->is_con() &&
757 (shift_t->get_con() == 0 || shift_t->get_con() == (mask + 1))) {
758 return lshift;
759 }
760 }
761 return NULL;
762 }
763
764 Node* OrINode::Ideal(PhaseGVN* phase, bool can_reshape) {
765 int lopcode = in(1)->Opcode();
766 int ropcode = in(2)->Opcode();
767 if (Matcher::match_rule_supported(Op_RotateLeft) &&
768 lopcode == Op_LShiftI && ropcode == Op_URShiftI && in(1)->in(1) == in(2)->in(1)) {
769 Node* lshift = in(1)->in(2);
770 Node* rshift = in(2)->in(2);
771 Node* shift = rotate_shift(phase, lshift, rshift, 0x1F);
772 if (shift != NULL) {
773 return new RotateLeftNode(in(1)->in(1), shift, TypeInt::INT);
774 }
775 return NULL;
776 }
777 if (Matcher::match_rule_supported(Op_RotateRight) &&
778 lopcode == Op_URShiftI && ropcode == Op_LShiftI && in(1)->in(1) == in(2)->in(1)) {
779 Node* rshift = in(1)->in(2);
780 Node* lshift = in(2)->in(2);
781 Node* shift = rotate_shift(phase, rshift, lshift, 0x1F);
782 if (shift != NULL) {
783 return new RotateRightNode(in(1)->in(1), shift, TypeInt::INT);
784 }
785 }
786 return NULL;
787 }
788
789 //------------------------------add_ring---------------------------------------
790 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
791 // the logical operations the ring's ADD is really a logical OR function.
792 // This also type-checks the inputs for sanity. Guaranteed never to
793 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
794 const Type *OrINode::add_ring( const Type *t0, const Type *t1 ) const {
795 const TypeInt *r0 = t0->is_int(); // Handy access
796 const TypeInt *r1 = t1->is_int();
797
798 // If both args are bool, can figure out better types
799 if ( r0 == TypeInt::BOOL ) {
800 if ( r1 == TypeInt::ONE) {
801 return TypeInt::ONE;
802 } else if ( r1 == TypeInt::BOOL ) {
803 return TypeInt::BOOL;
804 }
805 } else if ( r0 == TypeInt::ONE ) {
806 if ( r1 == TypeInt::BOOL ) {
807 return TypeInt::ONE;
808 }
809 }
810
811 // If either input is not a constant, just return all integers.
812 if( !r0->is_con() || !r1->is_con() )
813 return TypeInt::INT; // Any integer, but still no symbols.
814
815 // Otherwise just OR them bits.
816 return TypeInt::make( r0->get_con() | r1->get_con() );
817 }
818
819 //=============================================================================
820 //------------------------------Identity---------------------------------------
821 Node* OrLNode::Identity(PhaseGVN* phase) {
822 // x | x => x
823 if (in(1) == in(2)) {
824 return in(1);
825 }
826
827 return AddNode::Identity(phase);
828 }
829
830 Node* OrLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
831 int lopcode = in(1)->Opcode();
832 int ropcode = in(2)->Opcode();
833 if (Matcher::match_rule_supported(Op_RotateLeft) &&
834 lopcode == Op_LShiftL && ropcode == Op_URShiftL && in(1)->in(1) == in(2)->in(1)) {
835 Node* lshift = in(1)->in(2);
836 Node* rshift = in(2)->in(2);
837 Node* shift = rotate_shift(phase, lshift, rshift, 0x3F);
838 if (shift != NULL) {
839 return new RotateLeftNode(in(1)->in(1), shift, TypeLong::LONG);
840 }
841 return NULL;
842 }
843 if (Matcher::match_rule_supported(Op_RotateRight) &&
844 lopcode == Op_URShiftL && ropcode == Op_LShiftL && in(1)->in(1) == in(2)->in(1)) {
845 Node* rshift = in(1)->in(2);
846 Node* lshift = in(2)->in(2);
847 Node* shift = rotate_shift(phase, rshift, lshift, 0x3F);
848 if (shift != NULL) {
849 return new RotateRightNode(in(1)->in(1), shift, TypeLong::LONG);
850 }
851 }
852 return NULL;
853 }
854
855 //------------------------------add_ring---------------------------------------
856 const Type *OrLNode::add_ring( const Type *t0, const Type *t1 ) const {
857 const TypeLong *r0 = t0->is_long(); // Handy access
858 const TypeLong *r1 = t1->is_long();
859
860 // If either input is not a constant, just return all integers.
861 if( !r0->is_con() || !r1->is_con() )
862 return TypeLong::LONG; // Any integer, but still no symbols.
863
864 // Otherwise just OR them bits.
865 return TypeLong::make( r0->get_con() | r1->get_con() );
866 }
867
868 //---------------------------Helper -------------------------------------------
869 /* Decide if the given node is used only in arithmetic expressions(add or sub).
870 */
871 static bool is_used_in_only_arithmetic(Node* n, BasicType bt) {
872 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
873 Node* u = n->fast_out(i);
874 if (u->Opcode() != Op_Add(bt) && u->Opcode() != Op_Sub(bt)) {
875 return false;
876 }
877 }
878 return true;
879 }
880
881 //=============================================================================
882 //------------------------------Idealize---------------------------------------
883 Node* XorINode::Ideal(PhaseGVN* phase, bool can_reshape) {
884 Node* in1 = in(1);
885 Node* in2 = in(2);
886
887 // Convert ~x into -1-x when ~x is used in an arithmetic expression
888 // or x itself is an expression.
889 if (phase->type(in2) == TypeInt::MINUS_1) { // follows LHS^(-1), i.e., ~LHS
890 if (phase->is_IterGVN()) {
891 if (is_used_in_only_arithmetic(this, T_INT)
892 // LHS is arithmetic
893 || (in1->Opcode() == Op_AddI || in1->Opcode() == Op_SubI)) {
894 return new SubINode(in2, in1);
895 }
896 } else {
897 // graph could be incomplete in GVN so we postpone to IGVN
898 phase->record_for_igvn(this);
899 }
900 }
901 return AddNode::Ideal(phase, can_reshape);
902 }
903
904 const Type* XorINode::Value(PhaseGVN* phase) const {
905 Node* in1 = in(1);
906 Node* in2 = in(2);
907 const Type* t1 = phase->type(in1);
908 const Type* t2 = phase->type(in2);
909 if (t1 == Type::TOP || t2 == Type::TOP) {
910 return Type::TOP;
911 }
912 // x ^ x ==> 0
913 if (in1->eqv_uncast(in2)) {
914 return add_id();
915 }
916 // result of xor can only have bits sets where any of the
917 // inputs have bits set. lo can always become 0.
918 const TypeInt* t1i = t1->is_int();
919 const TypeInt* t2i = t2->is_int();
920 if ((t1i->_lo >= 0) &&
921 (t1i->_hi > 0) &&
922 (t2i->_lo >= 0) &&
923 (t2i->_hi > 0)) {
924 // hi - set all bits below the highest bit. Using round_down to avoid overflow.
925 const TypeInt* t1x = TypeInt::make(0, round_down_power_of_2(t1i->_hi) + (round_down_power_of_2(t1i->_hi) - 1), t1i->_widen);
926 const TypeInt* t2x = TypeInt::make(0, round_down_power_of_2(t2i->_hi) + (round_down_power_of_2(t2i->_hi) - 1), t2i->_widen);
927 return t1x->meet(t2x);
928 }
929 return AddNode::Value(phase);
930 }
931
932
933 //------------------------------add_ring---------------------------------------
934 // Supplied function returns the sum of the inputs IN THE CURRENT RING. For
935 // the logical operations the ring's ADD is really a logical OR function.
936 // This also type-checks the inputs for sanity. Guaranteed never to
937 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
938 const Type *XorINode::add_ring( const Type *t0, const Type *t1 ) const {
939 const TypeInt *r0 = t0->is_int(); // Handy access
940 const TypeInt *r1 = t1->is_int();
941
942 // Complementing a boolean?
943 if( r0 == TypeInt::BOOL && ( r1 == TypeInt::ONE
944 || r1 == TypeInt::BOOL))
945 return TypeInt::BOOL;
946
947 if( !r0->is_con() || !r1->is_con() ) // Not constants
948 return TypeInt::INT; // Any integer, but still no symbols.
949
950 // Otherwise just XOR them bits.
951 return TypeInt::make( r0->get_con() ^ r1->get_con() );
952 }
953
954 //=============================================================================
955 //------------------------------add_ring---------------------------------------
956 const Type *XorLNode::add_ring( const Type *t0, const Type *t1 ) const {
957 const TypeLong *r0 = t0->is_long(); // Handy access
958 const TypeLong *r1 = t1->is_long();
959
960 // If either input is not a constant, just return all integers.
961 if( !r0->is_con() || !r1->is_con() )
962 return TypeLong::LONG; // Any integer, but still no symbols.
963
964 // Otherwise just OR them bits.
965 return TypeLong::make( r0->get_con() ^ r1->get_con() );
966 }
967
968 Node* XorLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
969 Node* in1 = in(1);
970 Node* in2 = in(2);
971
972 // Convert ~x into -1-x when ~x is used in an arithmetic expression
973 // or x itself is an arithmetic expression.
974 if (phase->type(in2) == TypeLong::MINUS_1) { // follows LHS^(-1), i.e., ~LHS
975 if (phase->is_IterGVN()) {
976 if (is_used_in_only_arithmetic(this, T_LONG)
977 // LHS is arithmetic
978 || (in1->Opcode() == Op_AddL || in1->Opcode() == Op_SubL)) {
979 return new SubLNode(in2, in1);
980 }
981 } else {
982 // graph could be incomplete in GVN so we postpone to IGVN
983 phase->record_for_igvn(this);
984 }
985 }
986 return AddNode::Ideal(phase, can_reshape);
987 }
988
989 const Type* XorLNode::Value(PhaseGVN* phase) const {
990 Node* in1 = in(1);
991 Node* in2 = in(2);
992 const Type* t1 = phase->type(in1);
993 const Type* t2 = phase->type(in2);
994 if (t1 == Type::TOP || t2 == Type::TOP) {
995 return Type::TOP;
996 }
997 // x ^ x ==> 0
998 if (in1->eqv_uncast(in2)) {
999 return add_id();
1000 }
1001 // result of xor can only have bits sets where any of the
1002 // inputs have bits set. lo can always become 0.
1003 const TypeLong* t1l = t1->is_long();
1004 const TypeLong* t2l = t2->is_long();
1005 if ((t1l->_lo >= 0) &&
1006 (t1l->_hi > 0) &&
1007 (t2l->_lo >= 0) &&
1008 (t2l->_hi > 0)) {
1009 // hi - set all bits below the highest bit. Using round_down to avoid overflow.
1010 const TypeLong* t1x = TypeLong::make(0, round_down_power_of_2(t1l->_hi) + (round_down_power_of_2(t1l->_hi) - 1), t1l->_widen);
1011 const TypeLong* t2x = TypeLong::make(0, round_down_power_of_2(t2l->_hi) + (round_down_power_of_2(t2l->_hi) - 1), t2l->_widen);
1012 return t1x->meet(t2x);
1013 }
1014 return AddNode::Value(phase);
1015 }
1016
1017 Node* MaxNode::build_min_max(Node* a, Node* b, bool is_max, bool is_unsigned, const Type* t, PhaseGVN& gvn) {
1018 bool is_int = gvn.type(a)->isa_int();
1019 assert(is_int || gvn.type(a)->isa_long(), "int or long inputs");
1020 assert(is_int == (gvn.type(b)->isa_int() != NULL), "inconsistent inputs");
1021 BasicType bt = is_int ? T_INT: T_LONG;
1022 Node* hook = NULL;
1023 if (gvn.is_IterGVN()) {
1024 // Make sure a and b are not destroyed
1025 hook = new Node(2);
1026 hook->init_req(0, a);
1027 hook->init_req(1, b);
1028 }
1029 Node* res = NULL;
1030 if (is_int && !is_unsigned) {
1031 if (is_max) {
1032 res = gvn.transform(new MaxINode(a, b));
1033 assert(gvn.type(res)->is_int()->_lo >= t->is_int()->_lo && gvn.type(res)->is_int()->_hi <= t->is_int()->_hi, "type doesn't match");
1034 } else {
1035 Node* res = gvn.transform(new MinINode(a, b));
1036 assert(gvn.type(res)->is_int()->_lo >= t->is_int()->_lo && gvn.type(res)->is_int()->_hi <= t->is_int()->_hi, "type doesn't match");
1037 }
1038 } else {
1039 Node* cmp = NULL;
1040 if (is_max) {
1041 cmp = gvn.transform(CmpNode::make(a, b, bt, is_unsigned));
1042 } else {
1043 cmp = gvn.transform(CmpNode::make(b, a, bt, is_unsigned));
1044 }
1045 Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::lt));
1046 res = gvn.transform(CMoveNode::make(NULL, bol, a, b, t));
1047 }
1048 if (hook != NULL) {
1049 hook->destruct(&gvn);
1050 }
1051 return res;
1052 }
1053
1054 Node* MaxNode::build_min_max_diff_with_zero(Node* a, Node* b, bool is_max, const Type* t, PhaseGVN& gvn) {
1055 bool is_int = gvn.type(a)->isa_int();
1056 assert(is_int || gvn.type(a)->isa_long(), "int or long inputs");
1057 assert(is_int == (gvn.type(b)->isa_int() != NULL), "inconsistent inputs");
1058 BasicType bt = is_int ? T_INT: T_LONG;
1059 Node* zero = gvn.integercon(0, bt);
1060 Node* hook = NULL;
1061 if (gvn.is_IterGVN()) {
1062 // Make sure a and b are not destroyed
1063 hook = new Node(2);
1064 hook->init_req(0, a);
1065 hook->init_req(1, b);
1066 }
1067 Node* cmp = NULL;
1068 if (is_max) {
1069 cmp = gvn.transform(CmpNode::make(a, b, bt, false));
1070 } else {
1071 cmp = gvn.transform(CmpNode::make(b, a, bt, false));
1072 }
1073 Node* sub = gvn.transform(SubNode::make(a, b, bt));
1074 Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::lt));
1075 Node* res = gvn.transform(CMoveNode::make(NULL, bol, sub, zero, t));
1076 if (hook != NULL) {
1077 hook->destruct(&gvn);
1078 }
1079 return res;
1080 }
1081
1082 //=============================================================================
1083 //------------------------------add_ring---------------------------------------
1084 // Supplied function returns the sum of the inputs.
1085 const Type *MaxINode::add_ring( const Type *t0, const Type *t1 ) const {
1086 const TypeInt *r0 = t0->is_int(); // Handy access
1087 const TypeInt *r1 = t1->is_int();
1088
1089 // Otherwise just MAX them bits.
1090 return TypeInt::make( MAX2(r0->_lo,r1->_lo), MAX2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
1091 }
1092
1093 // Check if addition of an integer with type 't' and a constant 'c' can overflow
1094 static bool can_overflow(const TypeInt* t, jint c) {
1095 jint t_lo = t->_lo;
1096 jint t_hi = t->_hi;
1097 return ((c < 0 && (java_add(t_lo, c) > t_lo)) ||
1098 (c > 0 && (java_add(t_hi, c) < t_hi)));
1099 }
1100
1101 // Ideal transformations for MaxINode
1102 Node* MaxINode::Ideal(PhaseGVN* phase, bool can_reshape) {
1103 // Force a right-spline graph
1104 Node* l = in(1);
1105 Node* r = in(2);
1106 // Transform MaxI1(MaxI2(a, b), c) into MaxI1(a, MaxI2(b, c))
1107 // to force a right-spline graph for the rest of MaxINode::Ideal().
1108 if (l->Opcode() == Op_MaxI) {
1109 assert(l != l->in(1), "dead loop in MaxINode::Ideal");
1110 r = phase->transform(new MaxINode(l->in(2), r));
1111 l = l->in(1);
1112 set_req_X(1, l, phase);
1113 set_req_X(2, r, phase);
1114 return this;
1115 }
1116
1117 // Get left input & constant
1118 Node* x = l;
1119 jint x_off = 0;
1120 if (x->Opcode() == Op_AddI && // Check for "x+c0" and collect constant
1121 x->in(2)->is_Con()) {
1122 const Type* t = x->in(2)->bottom_type();
1123 if (t == Type::TOP) return NULL; // No progress
1124 x_off = t->is_int()->get_con();
1125 x = x->in(1);
1126 }
1127
1128 // Scan a right-spline-tree for MAXs
1129 Node* y = r;
1130 jint y_off = 0;
1131 // Check final part of MAX tree
1132 if (y->Opcode() == Op_AddI && // Check for "y+c1" and collect constant
1133 y->in(2)->is_Con()) {
1134 const Type* t = y->in(2)->bottom_type();
1135 if (t == Type::TOP) return NULL; // No progress
1136 y_off = t->is_int()->get_con();
1137 y = y->in(1);
1138 }
1139 if (x->_idx > y->_idx && r->Opcode() != Op_MaxI) {
1140 swap_edges(1, 2);
1141 return this;
1142 }
1143
1144 const TypeInt* tx = phase->type(x)->isa_int();
1145
1146 if (r->Opcode() == Op_MaxI) {
1147 assert(r != r->in(2), "dead loop in MaxINode::Ideal");
1148 y = r->in(1);
1149 // Check final part of MAX tree
1150 if (y->Opcode() == Op_AddI &&// Check for "y+c1" and collect constant
1151 y->in(2)->is_Con()) {
1152 const Type* t = y->in(2)->bottom_type();
1153 if (t == Type::TOP) return NULL; // No progress
1154 y_off = t->is_int()->get_con();
1155 y = y->in(1);
1156 }
1157
1158 if (x->_idx > y->_idx)
1159 return new MaxINode(r->in(1), phase->transform(new MaxINode(l, r->in(2))));
1160
1161 // Transform MAX2(x + c0, MAX2(x + c1, z)) into MAX2(x + MAX2(c0, c1), z)
1162 // if x == y and the additions can't overflow.
1163 if (x == y && tx != NULL &&
1164 !can_overflow(tx, x_off) &&
1165 !can_overflow(tx, y_off)) {
1166 return new MaxINode(phase->transform(new AddINode(x, phase->intcon(MAX2(x_off, y_off)))), r->in(2));
1167 }
1168 } else {
1169 // Transform MAX2(x + c0, y + c1) into x + MAX2(c0, c1)
1170 // if x == y and the additions can't overflow.
1171 if (x == y && tx != NULL &&
1172 !can_overflow(tx, x_off) &&
1173 !can_overflow(tx, y_off)) {
1174 return new AddINode(x, phase->intcon(MAX2(x_off, y_off)));
1175 }
1176 }
1177 return NULL;
1178 }
1179
1180 //=============================================================================
1181 //------------------------------Idealize---------------------------------------
1182 // MINs show up in range-check loop limit calculations. Look for
1183 // "MIN2(x+c0,MIN2(y,x+c1))". Pick the smaller constant: "MIN2(x+c0,y)"
1184 Node *MinINode::Ideal(PhaseGVN *phase, bool can_reshape) {
1185 Node *progress = NULL;
1186 // Force a right-spline graph
1187 Node *l = in(1);
1188 Node *r = in(2);
1189 // Transform MinI1( MinI2(a,b), c) into MinI1( a, MinI2(b,c) )
1190 // to force a right-spline graph for the rest of MinINode::Ideal().
1191 if( l->Opcode() == Op_MinI ) {
1192 assert( l != l->in(1), "dead loop in MinINode::Ideal" );
1193 r = phase->transform(new MinINode(l->in(2),r));
1194 l = l->in(1);
1195 set_req_X(1, l, phase);
1196 set_req_X(2, r, phase);
1197 return this;
1198 }
1199
1200 // Get left input & constant
1201 Node *x = l;
1202 jint x_off = 0;
1203 if( x->Opcode() == Op_AddI && // Check for "x+c0" and collect constant
1204 x->in(2)->is_Con() ) {
1205 const Type *t = x->in(2)->bottom_type();
1206 if( t == Type::TOP ) return NULL; // No progress
1207 x_off = t->is_int()->get_con();
1208 x = x->in(1);
1209 }
1210
1211 // Scan a right-spline-tree for MINs
1212 Node *y = r;
1213 jint y_off = 0;
1214 // Check final part of MIN tree
1215 if( y->Opcode() == Op_AddI && // Check for "y+c1" and collect constant
1216 y->in(2)->is_Con() ) {
1217 const Type *t = y->in(2)->bottom_type();
1218 if( t == Type::TOP ) return NULL; // No progress
1219 y_off = t->is_int()->get_con();
1220 y = y->in(1);
1221 }
1222 if( x->_idx > y->_idx && r->Opcode() != Op_MinI ) {
1223 swap_edges(1, 2);
1224 return this;
1225 }
1226
1227 const TypeInt* tx = phase->type(x)->isa_int();
1228
1229 if( r->Opcode() == Op_MinI ) {
1230 assert( r != r->in(2), "dead loop in MinINode::Ideal" );
1231 y = r->in(1);
1232 // Check final part of MIN tree
1233 if( y->Opcode() == Op_AddI &&// Check for "y+c1" and collect constant
1234 y->in(2)->is_Con() ) {
1235 const Type *t = y->in(2)->bottom_type();
1236 if( t == Type::TOP ) return NULL; // No progress
1237 y_off = t->is_int()->get_con();
1238 y = y->in(1);
1239 }
1240
1241 if( x->_idx > y->_idx )
1242 return new MinINode(r->in(1),phase->transform(new MinINode(l,r->in(2))));
1243
1244 // Transform MIN2(x + c0, MIN2(x + c1, z)) into MIN2(x + MIN2(c0, c1), z)
1245 // if x == y and the additions can't overflow.
1246 if (x == y && tx != NULL &&
1247 !can_overflow(tx, x_off) &&
1248 !can_overflow(tx, y_off)) {
1249 return new MinINode(phase->transform(new AddINode(x, phase->intcon(MIN2(x_off, y_off)))), r->in(2));
1250 }
1251 } else {
1252 // Transform MIN2(x + c0, y + c1) into x + MIN2(c0, c1)
1253 // if x == y and the additions can't overflow.
1254 if (x == y && tx != NULL &&
1255 !can_overflow(tx, x_off) &&
1256 !can_overflow(tx, y_off)) {
1257 return new AddINode(x,phase->intcon(MIN2(x_off,y_off)));
1258 }
1259 }
1260 return NULL;
1261 }
1262
1263 //------------------------------add_ring---------------------------------------
1264 // Supplied function returns the sum of the inputs.
1265 const Type *MinINode::add_ring( const Type *t0, const Type *t1 ) const {
1266 const TypeInt *r0 = t0->is_int(); // Handy access
1267 const TypeInt *r1 = t1->is_int();
1268
1269 // Otherwise just MIN them bits.
1270 return TypeInt::make( MIN2(r0->_lo,r1->_lo), MIN2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
1271 }
1272
1273 //------------------------------add_ring---------------------------------------
1274 const Type *MinFNode::add_ring( const Type *t0, const Type *t1 ) const {
1275 const TypeF *r0 = t0->is_float_constant();
1276 const TypeF *r1 = t1->is_float_constant();
1277
1278 if (r0->is_nan()) {
1279 return r0;
1280 }
1281 if (r1->is_nan()) {
1282 return r1;
1283 }
1284
1285 float f0 = r0->getf();
1286 float f1 = r1->getf();
1287 if (f0 != 0.0f || f1 != 0.0f) {
1288 return f0 < f1 ? r0 : r1;
1289 }
1290
1291 // handle min of 0.0, -0.0 case.
1292 return (jint_cast(f0) < jint_cast(f1)) ? r0 : r1;
1293 }
1294
1295 //------------------------------add_ring---------------------------------------
1296 const Type *MinDNode::add_ring( const Type *t0, const Type *t1 ) const {
1297 const TypeD *r0 = t0->is_double_constant();
1298 const TypeD *r1 = t1->is_double_constant();
1299
1300 if (r0->is_nan()) {
1301 return r0;
1302 }
1303 if (r1->is_nan()) {
1304 return r1;
1305 }
1306
1307 double d0 = r0->getd();
1308 double d1 = r1->getd();
1309 if (d0 != 0.0 || d1 != 0.0) {
1310 return d0 < d1 ? r0 : r1;
1311 }
1312
1313 // handle min of 0.0, -0.0 case.
1314 return (jlong_cast(d0) < jlong_cast(d1)) ? r0 : r1;
1315 }
1316
1317 //------------------------------add_ring---------------------------------------
1318 const Type *MaxFNode::add_ring( const Type *t0, const Type *t1 ) const {
1319 const TypeF *r0 = t0->is_float_constant();
1320 const TypeF *r1 = t1->is_float_constant();
1321
1322 if (r0->is_nan()) {
1323 return r0;
1324 }
1325 if (r1->is_nan()) {
1326 return r1;
1327 }
1328
1329 float f0 = r0->getf();
1330 float f1 = r1->getf();
1331 if (f0 != 0.0f || f1 != 0.0f) {
1332 return f0 > f1 ? r0 : r1;
1333 }
1334
1335 // handle max of 0.0,-0.0 case.
1336 return (jint_cast(f0) > jint_cast(f1)) ? r0 : r1;
1337 }
1338
1339 //------------------------------add_ring---------------------------------------
1340 const Type *MaxDNode::add_ring( const Type *t0, const Type *t1 ) const {
1341 const TypeD *r0 = t0->is_double_constant();
1342 const TypeD *r1 = t1->is_double_constant();
1343
1344 if (r0->is_nan()) {
1345 return r0;
1346 }
1347 if (r1->is_nan()) {
1348 return r1;
1349 }
1350
1351 double d0 = r0->getd();
1352 double d1 = r1->getd();
1353 if (d0 != 0.0 || d1 != 0.0) {
1354 return d0 > d1 ? r0 : r1;
1355 }
1356
1357 // handle max of 0.0, -0.0 case.
1358 return (jlong_cast(d0) > jlong_cast(d1)) ? r0 : r1;
1359 }