1 /*
2 * Copyright (c) 1997, 2021, 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/connode.hpp"
29 #include "opto/convertnode.hpp"
30 #include "opto/memnode.hpp"
31 #include "opto/mulnode.hpp"
32 #include "opto/phaseX.hpp"
33 #include "opto/subnode.hpp"
34 #include "utilities/powerOfTwo.hpp"
35
36 // Portions of code courtesy of Clifford Click
37
38
39 //=============================================================================
40 //------------------------------hash-------------------------------------------
41 // Hash function over MulNodes. Needs to be commutative; i.e., I swap
42 // (commute) inputs to MulNodes willy-nilly so the hash function must return
43 // the same value in the presence of edge swapping.
44 uint MulNode::hash() const {
45 return (uintptr_t)in(1) + (uintptr_t)in(2) + Opcode();
46 }
47
48 //------------------------------Identity---------------------------------------
49 // Multiplying a one preserves the other argument
50 Node* MulNode::Identity(PhaseGVN* phase) {
51 const Type *one = mul_id(); // The multiplicative identity
52 if( phase->type( in(1) )->higher_equal( one ) ) return in(2);
53 if( phase->type( in(2) )->higher_equal( one ) ) return in(1);
54
55 return this;
56 }
57
58 //------------------------------Ideal------------------------------------------
59 // We also canonicalize the Node, moving constants to the right input,
60 // and flatten expressions (so that 1+x+2 becomes x+3).
61 Node *MulNode::Ideal(PhaseGVN *phase, bool can_reshape) {
62 Node* in1 = in(1);
63 Node* in2 = in(2);
64 Node* progress = NULL; // Progress flag
65
66 // This code is used by And nodes too, but some conversions are
67 // only valid for the actual Mul nodes.
68 uint op = Opcode();
69 bool real_mul = (op == Op_MulI) || (op == Op_MulL) ||
70 (op == Op_MulF) || (op == Op_MulD);
71
72 // Convert "(-a)*(-b)" into "a*b".
73 if (real_mul && in1->is_Sub() && in2->is_Sub()) {
74 if (phase->type(in1->in(1))->is_zero_type() &&
75 phase->type(in2->in(1))->is_zero_type()) {
76 set_req(1, in1->in(2));
77 set_req(2, in2->in(2));
78 PhaseIterGVN* igvn = phase->is_IterGVN();
79 if (igvn) {
80 igvn->_worklist.push(in1);
81 igvn->_worklist.push(in2);
82 }
83 in1 = in(1);
84 in2 = in(2);
85 progress = this;
86 }
87 }
88
89 // convert "max(a,b) * min(a,b)" into "a*b".
90 if ((in(1)->Opcode() == max_opcode() && in(2)->Opcode() == min_opcode())
91 || (in(1)->Opcode() == min_opcode() && in(2)->Opcode() == max_opcode())) {
92 Node *in11 = in(1)->in(1);
93 Node *in12 = in(1)->in(2);
94
95 Node *in21 = in(2)->in(1);
96 Node *in22 = in(2)->in(2);
97
98 if ((in11 == in21 && in12 == in22) ||
99 (in11 == in22 && in12 == in21)) {
100 set_req(1, in11);
101 set_req(2, in12);
102 PhaseIterGVN* igvn = phase->is_IterGVN();
103 if (igvn) {
104 igvn->_worklist.push(in1);
105 igvn->_worklist.push(in2);
106 }
107 in1 = in(1);
108 in2 = in(2);
109 progress = this;
110 }
111 }
112
113 const Type* t1 = phase->type(in1);
114 const Type* t2 = phase->type(in2);
115
116 // We are OK if right is a constant, or right is a load and
117 // left is a non-constant.
118 if( !(t2->singleton() ||
119 (in(2)->is_Load() && !(t1->singleton() || in(1)->is_Load())) ) ) {
120 if( t1->singleton() || // Left input is a constant?
121 // Otherwise, sort inputs (commutativity) to help value numbering.
122 (in(1)->_idx > in(2)->_idx) ) {
123 swap_edges(1, 2);
124 const Type *t = t1;
125 t1 = t2;
126 t2 = t;
127 progress = this; // Made progress
128 }
129 }
130
131 // If the right input is a constant, and the left input is a product of a
132 // constant, flatten the expression tree.
133 if( t2->singleton() && // Right input is a constant?
134 op != Op_MulF && // Float & double cannot reassociate
135 op != Op_MulD ) {
136 if( t2 == Type::TOP ) return NULL;
137 Node *mul1 = in(1);
138 #ifdef ASSERT
139 // Check for dead loop
140 int op1 = mul1->Opcode();
141 if ((mul1 == this) || (in(2) == this) ||
142 ((op1 == mul_opcode() || op1 == add_opcode()) &&
143 ((mul1->in(1) == this) || (mul1->in(2) == this) ||
144 (mul1->in(1) == mul1) || (mul1->in(2) == mul1)))) {
145 assert(false, "dead loop in MulNode::Ideal");
146 }
147 #endif
148
149 if( mul1->Opcode() == mul_opcode() ) { // Left input is a multiply?
150 // Mul of a constant?
151 const Type *t12 = phase->type( mul1->in(2) );
152 if( t12->singleton() && t12 != Type::TOP) { // Left input is an add of a constant?
153 // Compute new constant; check for overflow
154 const Type *tcon01 = ((MulNode*)mul1)->mul_ring(t2,t12);
155 if( tcon01->singleton() ) {
156 // The Mul of the flattened expression
157 set_req_X(1, mul1->in(1), phase);
158 set_req_X(2, phase->makecon(tcon01), phase);
159 t2 = tcon01;
160 progress = this; // Made progress
161 }
162 }
163 }
164 // If the right input is a constant, and the left input is an add of a
165 // constant, flatten the tree: (X+con1)*con0 ==> X*con0 + con1*con0
166 const Node *add1 = in(1);
167 if( add1->Opcode() == add_opcode() ) { // Left input is an add?
168 // Add of a constant?
169 const Type *t12 = phase->type( add1->in(2) );
170 if( t12->singleton() && t12 != Type::TOP ) { // Left input is an add of a constant?
171 assert( add1->in(1) != add1, "dead loop in MulNode::Ideal" );
172 // Compute new constant; check for overflow
173 const Type *tcon01 = mul_ring(t2,t12);
174 if( tcon01->singleton() ) {
175
176 // Convert (X+con1)*con0 into X*con0
177 Node *mul = clone(); // mul = ()*con0
178 mul->set_req(1,add1->in(1)); // mul = X*con0
179 mul = phase->transform(mul);
180
181 Node *add2 = add1->clone();
182 add2->set_req(1, mul); // X*con0 + con0*con1
183 add2->set_req(2, phase->makecon(tcon01) );
184 progress = add2;
185 }
186 }
187 } // End of is left input an add
188 } // End of is right input a Mul
189
190 return progress;
191 }
192
193 //------------------------------Value-----------------------------------------
194 const Type* MulNode::Value(PhaseGVN* phase) const {
195 const Type *t1 = phase->type( in(1) );
196 const Type *t2 = phase->type( in(2) );
197 // Either input is TOP ==> the result is TOP
198 if( t1 == Type::TOP ) return Type::TOP;
199 if( t2 == Type::TOP ) return Type::TOP;
200
201 // Either input is ZERO ==> the result is ZERO.
202 // Not valid for floats or doubles since +0.0 * -0.0 --> +0.0
203 int op = Opcode();
204 if( op == Op_MulI || op == Op_AndI || op == Op_MulL || op == Op_AndL ) {
205 const Type *zero = add_id(); // The multiplicative zero
206 if( t1->higher_equal( zero ) ) return zero;
207 if( t2->higher_equal( zero ) ) return zero;
208 }
209
210 // Code pattern on return from a call that returns an __Value. Can
211 // be optimized away if the return value turns out to be an oop.
212 if (op == Op_AndX &&
213 in(1) != NULL &&
214 in(1)->Opcode() == Op_CastP2X &&
215 in(1)->in(1) != NULL &&
216 phase->type(in(1)->in(1))->isa_oopptr() &&
217 t2->isa_intptr_t()->_lo >= 0 &&
218 t2->isa_intptr_t()->_hi <= MinObjAlignmentInBytesMask) {
219 return add_id();
220 }
221
222 // Either input is BOTTOM ==> the result is the local BOTTOM
223 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM )
224 return bottom_type();
225
226 #if defined(IA32)
227 // Can't trust native compilers to properly fold strict double
228 // multiplication with round-to-zero on this platform.
229 if (op == Op_MulD) {
230 return TypeD::DOUBLE;
231 }
232 #endif
233
234 return mul_ring(t1,t2); // Local flavor of type multiplication
235 }
236
237 //=============================================================================
238 //------------------------------Ideal------------------------------------------
239 // Check for power-of-2 multiply, then try the regular MulNode::Ideal
240 Node *MulINode::Ideal(PhaseGVN *phase, bool can_reshape) {
241 // Swap constant to right
242 jint con;
243 if ((con = in(1)->find_int_con(0)) != 0) {
244 swap_edges(1, 2);
245 // Finish rest of method to use info in 'con'
246 } else if ((con = in(2)->find_int_con(0)) == 0) {
247 return MulNode::Ideal(phase, can_reshape);
248 }
249
250 // Now we have a constant Node on the right and the constant in con
251 if (con == 0) return NULL; // By zero is handled by Value call
252 if (con == 1) return NULL; // By one is handled by Identity call
253
254 // Check for negative constant; if so negate the final result
255 bool sign_flip = false;
256
257 unsigned int abs_con = uabs(con);
258 if (abs_con != (unsigned int)con) {
259 sign_flip = true;
260 }
261
262 // Get low bit; check for being the only bit
263 Node *res = NULL;
264 unsigned int bit1 = abs_con & (0-abs_con); // Extract low bit
265 if (bit1 == abs_con) { // Found a power of 2?
266 res = new LShiftINode(in(1), phase->intcon(log2i_exact(bit1)));
267 } else {
268 // Check for constant with 2 bits set
269 unsigned int bit2 = abs_con - bit1;
270 bit2 = bit2 & (0 - bit2); // Extract 2nd bit
271 if (bit2 + bit1 == abs_con) { // Found all bits in con?
272 Node *n1 = phase->transform(new LShiftINode(in(1), phase->intcon(log2i_exact(bit1))));
273 Node *n2 = phase->transform(new LShiftINode(in(1), phase->intcon(log2i_exact(bit2))));
274 res = new AddINode(n2, n1);
275 } else if (is_power_of_2(abs_con + 1)) {
276 // Sleezy: power-of-2 - 1. Next time be generic.
277 unsigned int temp = abs_con + 1;
278 Node *n1 = phase->transform(new LShiftINode(in(1), phase->intcon(log2i_exact(temp))));
279 res = new SubINode(n1, in(1));
280 } else {
281 return MulNode::Ideal(phase, can_reshape);
282 }
283 }
284
285 if (sign_flip) { // Need to negate result?
286 res = phase->transform(res);// Transform, before making the zero con
287 res = new SubINode(phase->intcon(0),res);
288 }
289
290 return res; // Return final result
291 }
292
293 //------------------------------mul_ring---------------------------------------
294 // Compute the product type of two integer ranges into this node.
295 const Type *MulINode::mul_ring(const Type *t0, const Type *t1) const {
296 const TypeInt *r0 = t0->is_int(); // Handy access
297 const TypeInt *r1 = t1->is_int();
298
299 // Fetch endpoints of all ranges
300 jint lo0 = r0->_lo;
301 double a = (double)lo0;
302 jint hi0 = r0->_hi;
303 double b = (double)hi0;
304 jint lo1 = r1->_lo;
305 double c = (double)lo1;
306 jint hi1 = r1->_hi;
307 double d = (double)hi1;
308
309 // Compute all endpoints & check for overflow
310 int32_t A = java_multiply(lo0, lo1);
311 if( (double)A != a*c ) return TypeInt::INT; // Overflow?
312 int32_t B = java_multiply(lo0, hi1);
313 if( (double)B != a*d ) return TypeInt::INT; // Overflow?
314 int32_t C = java_multiply(hi0, lo1);
315 if( (double)C != b*c ) return TypeInt::INT; // Overflow?
316 int32_t D = java_multiply(hi0, hi1);
317 if( (double)D != b*d ) return TypeInt::INT; // Overflow?
318
319 if( A < B ) { lo0 = A; hi0 = B; } // Sort range endpoints
320 else { lo0 = B; hi0 = A; }
321 if( C < D ) {
322 if( C < lo0 ) lo0 = C;
323 if( D > hi0 ) hi0 = D;
324 } else {
325 if( D < lo0 ) lo0 = D;
326 if( C > hi0 ) hi0 = C;
327 }
328 return TypeInt::make(lo0, hi0, MAX2(r0->_widen,r1->_widen));
329 }
330
331
332 //=============================================================================
333 //------------------------------Ideal------------------------------------------
334 // Check for power-of-2 multiply, then try the regular MulNode::Ideal
335 Node *MulLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
336 // Swap constant to right
337 jlong con;
338 if ((con = in(1)->find_long_con(0)) != 0) {
339 swap_edges(1, 2);
340 // Finish rest of method to use info in 'con'
341 } else if ((con = in(2)->find_long_con(0)) == 0) {
342 return MulNode::Ideal(phase, can_reshape);
343 }
344
345 // Now we have a constant Node on the right and the constant in con
346 if (con == CONST64(0)) return NULL; // By zero is handled by Value call
347 if (con == CONST64(1)) return NULL; // By one is handled by Identity call
348
349 // Check for negative constant; if so negate the final result
350 bool sign_flip = false;
351 julong abs_con = uabs(con);
352 if (abs_con != (julong)con) {
353 sign_flip = true;
354 }
355
356 // Get low bit; check for being the only bit
357 Node *res = NULL;
358 julong bit1 = abs_con & (0-abs_con); // Extract low bit
359 if (bit1 == abs_con) { // Found a power of 2?
360 res = new LShiftLNode(in(1), phase->intcon(log2i_exact(bit1)));
361 } else {
362
363 // Check for constant with 2 bits set
364 julong bit2 = abs_con-bit1;
365 bit2 = bit2 & (0-bit2); // Extract 2nd bit
366 if (bit2 + bit1 == abs_con) { // Found all bits in con?
367 Node *n1 = phase->transform(new LShiftLNode(in(1), phase->intcon(log2i_exact(bit1))));
368 Node *n2 = phase->transform(new LShiftLNode(in(1), phase->intcon(log2i_exact(bit2))));
369 res = new AddLNode(n2, n1);
370
371 } else if (is_power_of_2(abs_con+1)) {
372 // Sleezy: power-of-2 -1. Next time be generic.
373 julong temp = abs_con + 1;
374 Node *n1 = phase->transform( new LShiftLNode(in(1), phase->intcon(log2i_exact(temp))));
375 res = new SubLNode(n1, in(1));
376 } else {
377 return MulNode::Ideal(phase, can_reshape);
378 }
379 }
380
381 if (sign_flip) { // Need to negate result?
382 res = phase->transform(res);// Transform, before making the zero con
383 res = new SubLNode(phase->longcon(0),res);
384 }
385
386 return res; // Return final result
387 }
388
389 //------------------------------mul_ring---------------------------------------
390 // Compute the product type of two integer ranges into this node.
391 const Type *MulLNode::mul_ring(const Type *t0, const Type *t1) const {
392 const TypeLong *r0 = t0->is_long(); // Handy access
393 const TypeLong *r1 = t1->is_long();
394
395 // Fetch endpoints of all ranges
396 jlong lo0 = r0->_lo;
397 double a = (double)lo0;
398 jlong hi0 = r0->_hi;
399 double b = (double)hi0;
400 jlong lo1 = r1->_lo;
401 double c = (double)lo1;
402 jlong hi1 = r1->_hi;
403 double d = (double)hi1;
404
405 // Compute all endpoints & check for overflow
406 jlong A = java_multiply(lo0, lo1);
407 if( (double)A != a*c ) return TypeLong::LONG; // Overflow?
408 jlong B = java_multiply(lo0, hi1);
409 if( (double)B != a*d ) return TypeLong::LONG; // Overflow?
410 jlong C = java_multiply(hi0, lo1);
411 if( (double)C != b*c ) return TypeLong::LONG; // Overflow?
412 jlong D = java_multiply(hi0, hi1);
413 if( (double)D != b*d ) return TypeLong::LONG; // Overflow?
414
415 if( A < B ) { lo0 = A; hi0 = B; } // Sort range endpoints
416 else { lo0 = B; hi0 = A; }
417 if( C < D ) {
418 if( C < lo0 ) lo0 = C;
419 if( D > hi0 ) hi0 = D;
420 } else {
421 if( D < lo0 ) lo0 = D;
422 if( C > hi0 ) hi0 = C;
423 }
424 return TypeLong::make(lo0, hi0, MAX2(r0->_widen,r1->_widen));
425 }
426
427 //=============================================================================
428 //------------------------------mul_ring---------------------------------------
429 // Compute the product type of two double ranges into this node.
430 const Type *MulFNode::mul_ring(const Type *t0, const Type *t1) const {
431 if( t0 == Type::FLOAT || t1 == Type::FLOAT ) return Type::FLOAT;
432 return TypeF::make( t0->getf() * t1->getf() );
433 }
434
435 //=============================================================================
436 //------------------------------mul_ring---------------------------------------
437 // Compute the product type of two double ranges into this node.
438 const Type *MulDNode::mul_ring(const Type *t0, const Type *t1) const {
439 if( t0 == Type::DOUBLE || t1 == Type::DOUBLE ) return Type::DOUBLE;
440 // We must be multiplying 2 double constants.
441 return TypeD::make( t0->getd() * t1->getd() );
442 }
443
444 //=============================================================================
445 //------------------------------Value------------------------------------------
446 const Type* MulHiLNode::Value(PhaseGVN* phase) const {
447 const Type *t1 = phase->type( in(1) );
448 const Type *t2 = phase->type( in(2) );
449 const Type *bot = bottom_type();
450 return MulHiValue(t1, t2, bot);
451 }
452
453 const Type* UMulHiLNode::Value(PhaseGVN* phase) const {
454 const Type *t1 = phase->type( in(1) );
455 const Type *t2 = phase->type( in(2) );
456 const Type *bot = bottom_type();
457 return MulHiValue(t1, t2, bot);
458 }
459
460 // A common routine used by UMulHiLNode and MulHiLNode
461 const Type* MulHiValue(const Type *t1, const Type *t2, const Type *bot) {
462 // Either input is TOP ==> the result is TOP
463 if( t1 == Type::TOP ) return Type::TOP;
464 if( t2 == Type::TOP ) return Type::TOP;
465
466 // Either input is BOTTOM ==> the result is the local BOTTOM
467 if( (t1 == bot) || (t2 == bot) ||
468 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
469 return bot;
470
471 // It is not worth trying to constant fold this stuff!
472 return TypeLong::LONG;
473 }
474
475 //=============================================================================
476 //------------------------------mul_ring---------------------------------------
477 // Supplied function returns the product of the inputs IN THE CURRENT RING.
478 // For the logical operations the ring's MUL is really a logical AND function.
479 // This also type-checks the inputs for sanity. Guaranteed never to
480 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
481 const Type *AndINode::mul_ring( const Type *t0, const Type *t1 ) const {
482 const TypeInt *r0 = t0->is_int(); // Handy access
483 const TypeInt *r1 = t1->is_int();
484 int widen = MAX2(r0->_widen,r1->_widen);
485
486 // If either input is a constant, might be able to trim cases
487 if( !r0->is_con() && !r1->is_con() )
488 return TypeInt::INT; // No constants to be had
489
490 // Both constants? Return bits
491 if( r0->is_con() && r1->is_con() )
492 return TypeInt::make( r0->get_con() & r1->get_con() );
493
494 if( r0->is_con() && r0->get_con() > 0 )
495 return TypeInt::make(0, r0->get_con(), widen);
496
497 if( r1->is_con() && r1->get_con() > 0 )
498 return TypeInt::make(0, r1->get_con(), widen);
499
500 if( r0 == TypeInt::BOOL || r1 == TypeInt::BOOL ) {
501 return TypeInt::BOOL;
502 }
503
504 return TypeInt::INT; // No constants to be had
505 }
506
507 //------------------------------Identity---------------------------------------
508 // Masking off the high bits of an unsigned load is not required
509 Node* AndINode::Identity(PhaseGVN* phase) {
510
511 // x & x => x
512 if (in(1) == in(2)) {
513 return in(1);
514 }
515
516 Node* in1 = in(1);
517 uint op = in1->Opcode();
518 const TypeInt* t2 = phase->type(in(2))->isa_int();
519 if (t2 && t2->is_con()) {
520 int con = t2->get_con();
521 // Masking off high bits which are always zero is useless.
522 const TypeInt* t1 = phase->type(in(1))->isa_int();
523 if (t1 != NULL && t1->_lo >= 0) {
524 jint t1_support = right_n_bits(1 + log2i_graceful(t1->_hi));
525 if ((t1_support & con) == t1_support)
526 return in1;
527 }
528 // Masking off the high bits of a unsigned-shift-right is not
529 // needed either.
530 if (op == Op_URShiftI) {
531 const TypeInt* t12 = phase->type(in1->in(2))->isa_int();
532 if (t12 && t12->is_con()) { // Shift is by a constant
533 int shift = t12->get_con();
534 shift &= BitsPerJavaInteger - 1; // semantics of Java shifts
535 int mask = max_juint >> shift;
536 if ((mask & con) == mask) // If AND is useless, skip it
537 return in1;
538 }
539 }
540 }
541 return MulNode::Identity(phase);
542 }
543
544 //------------------------------Ideal------------------------------------------
545 Node *AndINode::Ideal(PhaseGVN *phase, bool can_reshape) {
546 // Special case constant AND mask
547 const TypeInt *t2 = phase->type( in(2) )->isa_int();
548 if( !t2 || !t2->is_con() ) return MulNode::Ideal(phase, can_reshape);
549 const int mask = t2->get_con();
550 Node *load = in(1);
551 uint lop = load->Opcode();
552
553 // Masking bits off of a Character? Hi bits are already zero.
554 if( lop == Op_LoadUS &&
555 (mask & 0xFFFF0000) ) // Can we make a smaller mask?
556 return new AndINode(load,phase->intcon(mask&0xFFFF));
557
558 // Masking bits off of a Short? Loading a Character does some masking
559 if (can_reshape &&
560 load->outcnt() == 1 && load->unique_out() == this) {
561 if (lop == Op_LoadS && (mask & 0xFFFF0000) == 0 ) {
562 Node* ldus = load->as_Load()->convert_to_unsigned_load(*phase);
563 ldus = phase->transform(ldus);
564 return new AndINode(ldus, phase->intcon(mask & 0xFFFF));
565 }
566
567 // Masking sign bits off of a Byte? Do an unsigned byte load plus
568 // an and.
569 if (lop == Op_LoadB && (mask & 0xFFFFFF00) == 0) {
570 Node* ldub = load->as_Load()->convert_to_unsigned_load(*phase);
571 ldub = phase->transform(ldub);
572 return new AndINode(ldub, phase->intcon(mask));
573 }
574 }
575
576 // Masking off sign bits? Dont make them!
577 if( lop == Op_RShiftI ) {
578 const TypeInt *t12 = phase->type(load->in(2))->isa_int();
579 if( t12 && t12->is_con() ) { // Shift is by a constant
580 int shift = t12->get_con();
581 shift &= BitsPerJavaInteger-1; // semantics of Java shifts
582 const int sign_bits_mask = ~right_n_bits(BitsPerJavaInteger - shift);
583 // If the AND'ing of the 2 masks has no bits, then only original shifted
584 // bits survive. NO sign-extension bits survive the maskings.
585 if( (sign_bits_mask & mask) == 0 ) {
586 // Use zero-fill shift instead
587 Node *zshift = phase->transform(new URShiftINode(load->in(1),load->in(2)));
588 return new AndINode( zshift, in(2) );
589 }
590 }
591 }
592
593 // Check for 'negate/and-1', a pattern emitted when someone asks for
594 // 'mod 2'. Negate leaves the low order bit unchanged (think: complement
595 // plus 1) and the mask is of the low order bit. Skip the negate.
596 if( lop == Op_SubI && mask == 1 && load->in(1) &&
597 phase->type(load->in(1)) == TypeInt::ZERO )
598 return new AndINode( load->in(2), in(2) );
599
600 return MulNode::Ideal(phase, can_reshape);
601 }
602
603 //=============================================================================
604 //------------------------------mul_ring---------------------------------------
605 // Supplied function returns the product of the inputs IN THE CURRENT RING.
606 // For the logical operations the ring's MUL is really a logical AND function.
607 // This also type-checks the inputs for sanity. Guaranteed never to
608 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
609 const Type *AndLNode::mul_ring( const Type *t0, const Type *t1 ) const {
610 const TypeLong *r0 = t0->is_long(); // Handy access
611 const TypeLong *r1 = t1->is_long();
612 int widen = MAX2(r0->_widen,r1->_widen);
613
614 // If either input is a constant, might be able to trim cases
615 if( !r0->is_con() && !r1->is_con() )
616 return TypeLong::LONG; // No constants to be had
617
618 // Both constants? Return bits
619 if( r0->is_con() && r1->is_con() )
620 return TypeLong::make( r0->get_con() & r1->get_con() );
621
622 if( r0->is_con() && r0->get_con() > 0 )
623 return TypeLong::make(CONST64(0), r0->get_con(), widen);
624
625 if( r1->is_con() && r1->get_con() > 0 )
626 return TypeLong::make(CONST64(0), r1->get_con(), widen);
627
628 return TypeLong::LONG; // No constants to be had
629 }
630
631 //------------------------------Identity---------------------------------------
632 // Masking off the high bits of an unsigned load is not required
633 Node* AndLNode::Identity(PhaseGVN* phase) {
634
635 // x & x => x
636 if (in(1) == in(2)) {
637 return in(1);
638 }
639
640 Node *usr = in(1);
641 const TypeLong *t2 = phase->type( in(2) )->isa_long();
642 if( t2 && t2->is_con() ) {
643 jlong con = t2->get_con();
644 // Masking off high bits which are always zero is useless.
645 const TypeLong* t1 = phase->type( in(1) )->isa_long();
646 if (t1 != NULL && t1->_lo >= 0) {
647 int bit_count = log2i_graceful(t1->_hi) + 1;
648 jlong t1_support = jlong(max_julong >> (BitsPerJavaLong - bit_count));
649 if ((t1_support & con) == t1_support)
650 return usr;
651 }
652 uint lop = usr->Opcode();
653 // Masking off the high bits of a unsigned-shift-right is not
654 // needed either.
655 if( lop == Op_URShiftL ) {
656 const TypeInt *t12 = phase->type( usr->in(2) )->isa_int();
657 if( t12 && t12->is_con() ) { // Shift is by a constant
658 int shift = t12->get_con();
659 shift &= BitsPerJavaLong - 1; // semantics of Java shifts
660 jlong mask = max_julong >> shift;
661 if( (mask&con) == mask ) // If AND is useless, skip it
662 return usr;
663 }
664 }
665
666 // Check if this is part of an inline type test
667 if (con == markWord::inline_type_pattern && in(1)->is_Load() &&
668 phase->type(in(1)->in(MemNode::Address))->is_inlinetypeptr() &&
669 phase->type(in(1)->in(MemNode::Address))->is_ptr()->offset() == oopDesc::mark_offset_in_bytes()) {
670 assert(EnableValhalla, "should only be used for inline types");
671 return in(2); // Obj is known to be an inline type
672 }
673 }
674 return MulNode::Identity(phase);
675 }
676
677 //------------------------------Ideal------------------------------------------
678 Node *AndLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
679 // Special case constant AND mask
680 const TypeLong *t2 = phase->type( in(2) )->isa_long();
681 if( !t2 || !t2->is_con() ) return MulNode::Ideal(phase, can_reshape);
682 const jlong mask = t2->get_con();
683
684 Node* in1 = in(1);
685 uint op = in1->Opcode();
686
687 // Are we masking a long that was converted from an int with a mask
688 // that fits in 32-bits? Commute them and use an AndINode. Don't
689 // convert masks which would cause a sign extension of the integer
690 // value. This check includes UI2L masks (0x00000000FFFFFFFF) which
691 // would be optimized away later in Identity.
692 if (op == Op_ConvI2L && (mask & UCONST64(0xFFFFFFFF80000000)) == 0) {
693 Node* andi = new AndINode(in1->in(1), phase->intcon(mask));
694 andi = phase->transform(andi);
695 return new ConvI2LNode(andi);
696 }
697
698 // Masking off sign bits? Dont make them!
699 if (op == Op_RShiftL) {
700 const TypeInt* t12 = phase->type(in1->in(2))->isa_int();
701 if( t12 && t12->is_con() ) { // Shift is by a constant
702 int shift = t12->get_con();
703 shift &= BitsPerJavaLong - 1; // semantics of Java shifts
704 const jlong sign_bits_mask = ~(((jlong)CONST64(1) << (jlong)(BitsPerJavaLong - shift)) -1);
705 // If the AND'ing of the 2 masks has no bits, then only original shifted
706 // bits survive. NO sign-extension bits survive the maskings.
707 if( (sign_bits_mask & mask) == 0 ) {
708 // Use zero-fill shift instead
709 Node *zshift = phase->transform(new URShiftLNode(in1->in(1), in1->in(2)));
710 return new AndLNode(zshift, in(2));
711 }
712 }
713 }
714
715 return MulNode::Ideal(phase, can_reshape);
716 }
717
718 //=============================================================================
719
720 static bool const_shift_count(PhaseGVN* phase, Node* shiftNode, int* count) {
721 const TypeInt* tcount = phase->type(shiftNode->in(2))->isa_int();
722 if (tcount != NULL && tcount->is_con()) {
723 *count = tcount->get_con();
724 return true;
725 }
726 return false;
727 }
728
729 static int maskShiftAmount(PhaseGVN* phase, Node* shiftNode, int nBits) {
730 int count = 0;
731 if (const_shift_count(phase, shiftNode, &count)) {
732 int maskedShift = count & (nBits - 1);
733 if (maskedShift == 0) {
734 // Let Identity() handle 0 shift count.
735 return 0;
736 }
737
738 if (count != maskedShift) {
739 shiftNode->set_req(2, phase->intcon(maskedShift)); // Replace shift count with masked value.
740 PhaseIterGVN* igvn = phase->is_IterGVN();
741 if (igvn) {
742 igvn->rehash_node_delayed(shiftNode);
743 }
744 }
745 return maskedShift;
746 }
747 return 0;
748 }
749
750 //------------------------------Identity---------------------------------------
751 Node* LShiftINode::Identity(PhaseGVN* phase) {
752 int count = 0;
753 if (const_shift_count(phase, this, &count) && (count & (BitsPerJavaInteger - 1)) == 0) {
754 // Shift by a multiple of 32 does nothing
755 return in(1);
756 }
757 return this;
758 }
759
760 //------------------------------Ideal------------------------------------------
761 // If the right input is a constant, and the left input is an add of a
762 // constant, flatten the tree: (X+con1)<<con0 ==> X<<con0 + con1<<con0
763 Node *LShiftINode::Ideal(PhaseGVN *phase, bool can_reshape) {
764 int con = maskShiftAmount(phase, this, BitsPerJavaInteger);
765 if (con == 0) {
766 return NULL;
767 }
768
769 // Left input is an add of a constant?
770 Node *add1 = in(1);
771 int add1_op = add1->Opcode();
772 if( add1_op == Op_AddI ) { // Left input is an add?
773 assert( add1 != add1->in(1), "dead loop in LShiftINode::Ideal" );
774 const TypeInt *t12 = phase->type(add1->in(2))->isa_int();
775 if( t12 && t12->is_con() ){ // Left input is an add of a con?
776 // Transform is legal, but check for profit. Avoid breaking 'i2s'
777 // and 'i2b' patterns which typically fold into 'StoreC/StoreB'.
778 if( con < 16 ) {
779 // Compute X << con0
780 Node *lsh = phase->transform( new LShiftINode( add1->in(1), in(2) ) );
781 // Compute X<<con0 + (con1<<con0)
782 return new AddINode( lsh, phase->intcon(t12->get_con() << con));
783 }
784 }
785 }
786
787 // Check for "(x>>c0)<<c0" which just masks off low bits
788 if( (add1_op == Op_RShiftI || add1_op == Op_URShiftI ) &&
789 add1->in(2) == in(2) )
790 // Convert to "(x & -(1<<c0))"
791 return new AndINode(add1->in(1),phase->intcon( -(1<<con)));
792
793 // Check for "((x>>c0) & Y)<<c0" which just masks off more low bits
794 if( add1_op == Op_AndI ) {
795 Node *add2 = add1->in(1);
796 int add2_op = add2->Opcode();
797 if( (add2_op == Op_RShiftI || add2_op == Op_URShiftI ) &&
798 add2->in(2) == in(2) ) {
799 // Convert to "(x & (Y<<c0))"
800 Node *y_sh = phase->transform( new LShiftINode( add1->in(2), in(2) ) );
801 return new AndINode( add2->in(1), y_sh );
802 }
803 }
804
805 // Check for ((x & ((1<<(32-c0))-1)) << c0) which ANDs off high bits
806 // before shifting them away.
807 const jint bits_mask = right_n_bits(BitsPerJavaInteger-con);
808 if( add1_op == Op_AndI &&
809 phase->type(add1->in(2)) == TypeInt::make( bits_mask ) )
810 return new LShiftINode( add1->in(1), in(2) );
811
812 return NULL;
813 }
814
815 //------------------------------Value------------------------------------------
816 // A LShiftINode shifts its input2 left by input1 amount.
817 const Type* LShiftINode::Value(PhaseGVN* phase) const {
818 const Type *t1 = phase->type( in(1) );
819 const Type *t2 = phase->type( in(2) );
820 // Either input is TOP ==> the result is TOP
821 if( t1 == Type::TOP ) return Type::TOP;
822 if( t2 == Type::TOP ) return Type::TOP;
823
824 // Left input is ZERO ==> the result is ZERO.
825 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
826 // Shift by zero does nothing
827 if( t2 == TypeInt::ZERO ) return t1;
828
829 // Either input is BOTTOM ==> the result is BOTTOM
830 if( (t1 == TypeInt::INT) || (t2 == TypeInt::INT) ||
831 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
832 return TypeInt::INT;
833
834 const TypeInt *r1 = t1->is_int(); // Handy access
835 const TypeInt *r2 = t2->is_int(); // Handy access
836
837 if (!r2->is_con())
838 return TypeInt::INT;
839
840 uint shift = r2->get_con();
841 shift &= BitsPerJavaInteger-1; // semantics of Java shifts
842 // Shift by a multiple of 32 does nothing:
843 if (shift == 0) return t1;
844
845 // If the shift is a constant, shift the bounds of the type,
846 // unless this could lead to an overflow.
847 if (!r1->is_con()) {
848 jint lo = r1->_lo, hi = r1->_hi;
849 if (((lo << shift) >> shift) == lo &&
850 ((hi << shift) >> shift) == hi) {
851 // No overflow. The range shifts up cleanly.
852 return TypeInt::make((jint)lo << (jint)shift,
853 (jint)hi << (jint)shift,
854 MAX2(r1->_widen,r2->_widen));
855 }
856 return TypeInt::INT;
857 }
858
859 return TypeInt::make( (jint)r1->get_con() << (jint)shift );
860 }
861
862 //=============================================================================
863 //------------------------------Identity---------------------------------------
864 Node* LShiftLNode::Identity(PhaseGVN* phase) {
865 int count = 0;
866 if (const_shift_count(phase, this, &count) && (count & (BitsPerJavaLong - 1)) == 0) {
867 // Shift by a multiple of 64 does nothing
868 return in(1);
869 }
870 return this;
871 }
872
873 //------------------------------Ideal------------------------------------------
874 // If the right input is a constant, and the left input is an add of a
875 // constant, flatten the tree: (X+con1)<<con0 ==> X<<con0 + con1<<con0
876 Node *LShiftLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
877 int con = maskShiftAmount(phase, this, BitsPerJavaLong);
878 if (con == 0) {
879 return NULL;
880 }
881
882 // Left input is an add of a constant?
883 Node *add1 = in(1);
884 int add1_op = add1->Opcode();
885 if( add1_op == Op_AddL ) { // Left input is an add?
886 // Avoid dead data cycles from dead loops
887 assert( add1 != add1->in(1), "dead loop in LShiftLNode::Ideal" );
888 const TypeLong *t12 = phase->type(add1->in(2))->isa_long();
889 if( t12 && t12->is_con() ){ // Left input is an add of a con?
890 // Compute X << con0
891 Node *lsh = phase->transform( new LShiftLNode( add1->in(1), in(2) ) );
892 // Compute X<<con0 + (con1<<con0)
893 return new AddLNode( lsh, phase->longcon(t12->get_con() << con));
894 }
895 }
896
897 // Check for "(x>>c0)<<c0" which just masks off low bits
898 if( (add1_op == Op_RShiftL || add1_op == Op_URShiftL ) &&
899 add1->in(2) == in(2) )
900 // Convert to "(x & -(1<<c0))"
901 return new AndLNode(add1->in(1),phase->longcon( -(CONST64(1)<<con)));
902
903 // Check for "((x>>c0) & Y)<<c0" which just masks off more low bits
904 if( add1_op == Op_AndL ) {
905 Node *add2 = add1->in(1);
906 int add2_op = add2->Opcode();
907 if( (add2_op == Op_RShiftL || add2_op == Op_URShiftL ) &&
908 add2->in(2) == in(2) ) {
909 // Convert to "(x & (Y<<c0))"
910 Node *y_sh = phase->transform( new LShiftLNode( add1->in(2), in(2) ) );
911 return new AndLNode( add2->in(1), y_sh );
912 }
913 }
914
915 // Check for ((x & ((CONST64(1)<<(64-c0))-1)) << c0) which ANDs off high bits
916 // before shifting them away.
917 const jlong bits_mask = jlong(max_julong >> con);
918 if( add1_op == Op_AndL &&
919 phase->type(add1->in(2)) == TypeLong::make( bits_mask ) )
920 return new LShiftLNode( add1->in(1), in(2) );
921
922 return NULL;
923 }
924
925 //------------------------------Value------------------------------------------
926 // A LShiftLNode shifts its input2 left by input1 amount.
927 const Type* LShiftLNode::Value(PhaseGVN* phase) const {
928 const Type *t1 = phase->type( in(1) );
929 const Type *t2 = phase->type( in(2) );
930 // Either input is TOP ==> the result is TOP
931 if( t1 == Type::TOP ) return Type::TOP;
932 if( t2 == Type::TOP ) return Type::TOP;
933
934 // Left input is ZERO ==> the result is ZERO.
935 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
936 // Shift by zero does nothing
937 if( t2 == TypeInt::ZERO ) return t1;
938
939 // Either input is BOTTOM ==> the result is BOTTOM
940 if( (t1 == TypeLong::LONG) || (t2 == TypeInt::INT) ||
941 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
942 return TypeLong::LONG;
943
944 const TypeLong *r1 = t1->is_long(); // Handy access
945 const TypeInt *r2 = t2->is_int(); // Handy access
946
947 if (!r2->is_con())
948 return TypeLong::LONG;
949
950 uint shift = r2->get_con();
951 shift &= BitsPerJavaLong - 1; // semantics of Java shifts
952 // Shift by a multiple of 64 does nothing:
953 if (shift == 0) return t1;
954
955 // If the shift is a constant, shift the bounds of the type,
956 // unless this could lead to an overflow.
957 if (!r1->is_con()) {
958 jlong lo = r1->_lo, hi = r1->_hi;
959 if (((lo << shift) >> shift) == lo &&
960 ((hi << shift) >> shift) == hi) {
961 // No overflow. The range shifts up cleanly.
962 return TypeLong::make((jlong)lo << (jint)shift,
963 (jlong)hi << (jint)shift,
964 MAX2(r1->_widen,r2->_widen));
965 }
966 return TypeLong::LONG;
967 }
968
969 return TypeLong::make( (jlong)r1->get_con() << (jint)shift );
970 }
971
972 //=============================================================================
973 //------------------------------Identity---------------------------------------
974 Node* RShiftINode::Identity(PhaseGVN* phase) {
975 int count = 0;
976 if (const_shift_count(phase, this, &count)) {
977 if ((count & (BitsPerJavaInteger - 1)) == 0) {
978 // Shift by a multiple of 32 does nothing
979 return in(1);
980 }
981 // Check for useless sign-masking
982 if (in(1)->Opcode() == Op_LShiftI &&
983 in(1)->req() == 3 &&
984 in(1)->in(2) == in(2)) {
985 count &= BitsPerJavaInteger-1; // semantics of Java shifts
986 // Compute masks for which this shifting doesn't change
987 int lo = (-1 << (BitsPerJavaInteger - ((uint)count)-1)); // FFFF8000
988 int hi = ~lo; // 00007FFF
989 const TypeInt* t11 = phase->type(in(1)->in(1))->isa_int();
990 if (t11 == NULL) {
991 return this;
992 }
993 // Does actual value fit inside of mask?
994 if (lo <= t11->_lo && t11->_hi <= hi) {
995 return in(1)->in(1); // Then shifting is a nop
996 }
997 }
998 }
999 return this;
1000 }
1001
1002 //------------------------------Ideal------------------------------------------
1003 Node *RShiftINode::Ideal(PhaseGVN *phase, bool can_reshape) {
1004 // Inputs may be TOP if they are dead.
1005 const TypeInt *t1 = phase->type(in(1))->isa_int();
1006 if (!t1) return NULL; // Left input is an integer
1007 const TypeInt *t3; // type of in(1).in(2)
1008 int shift = maskShiftAmount(phase, this, BitsPerJavaInteger);
1009 if (shift == 0) {
1010 return NULL;
1011 }
1012
1013 // Check for (x & 0xFF000000) >> 24, whose mask can be made smaller.
1014 // Such expressions arise normally from shift chains like (byte)(x >> 24).
1015 const Node *mask = in(1);
1016 if( mask->Opcode() == Op_AndI &&
1017 (t3 = phase->type(mask->in(2))->isa_int()) &&
1018 t3->is_con() ) {
1019 Node *x = mask->in(1);
1020 jint maskbits = t3->get_con();
1021 // Convert to "(x >> shift) & (mask >> shift)"
1022 Node *shr_nomask = phase->transform( new RShiftINode(mask->in(1), in(2)) );
1023 return new AndINode(shr_nomask, phase->intcon( maskbits >> shift));
1024 }
1025
1026 // Check for "(short[i] <<16)>>16" which simply sign-extends
1027 const Node *shl = in(1);
1028 if( shl->Opcode() != Op_LShiftI ) return NULL;
1029
1030 if( shift == 16 &&
1031 (t3 = phase->type(shl->in(2))->isa_int()) &&
1032 t3->is_con(16) ) {
1033 Node *ld = shl->in(1);
1034 if( ld->Opcode() == Op_LoadS ) {
1035 // Sign extension is just useless here. Return a RShiftI of zero instead
1036 // returning 'ld' directly. We cannot return an old Node directly as
1037 // that is the job of 'Identity' calls and Identity calls only work on
1038 // direct inputs ('ld' is an extra Node removed from 'this'). The
1039 // combined optimization requires Identity only return direct inputs.
1040 set_req_X(1, ld, phase);
1041 set_req_X(2, phase->intcon(0), phase);
1042 return this;
1043 }
1044 else if (can_reshape &&
1045 ld->Opcode() == Op_LoadUS &&
1046 ld->outcnt() == 1 && ld->unique_out() == shl)
1047 // Replace zero-extension-load with sign-extension-load
1048 return ld->as_Load()->convert_to_signed_load(*phase);
1049 }
1050
1051 // Check for "(byte[i] <<24)>>24" which simply sign-extends
1052 if( shift == 24 &&
1053 (t3 = phase->type(shl->in(2))->isa_int()) &&
1054 t3->is_con(24) ) {
1055 Node *ld = shl->in(1);
1056 if (ld->Opcode() == Op_LoadB) {
1057 // Sign extension is just useless here
1058 set_req_X(1, ld, phase);
1059 set_req_X(2, phase->intcon(0), phase);
1060 return this;
1061 }
1062 }
1063
1064 return NULL;
1065 }
1066
1067 //------------------------------Value------------------------------------------
1068 // A RShiftINode shifts its input2 right by input1 amount.
1069 const Type* RShiftINode::Value(PhaseGVN* phase) const {
1070 const Type *t1 = phase->type( in(1) );
1071 const Type *t2 = phase->type( in(2) );
1072 // Either input is TOP ==> the result is TOP
1073 if( t1 == Type::TOP ) return Type::TOP;
1074 if( t2 == Type::TOP ) return Type::TOP;
1075
1076 // Left input is ZERO ==> the result is ZERO.
1077 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
1078 // Shift by zero does nothing
1079 if( t2 == TypeInt::ZERO ) return t1;
1080
1081 // Either input is BOTTOM ==> the result is BOTTOM
1082 if (t1 == Type::BOTTOM || t2 == Type::BOTTOM)
1083 return TypeInt::INT;
1084
1085 if (t2 == TypeInt::INT)
1086 return TypeInt::INT;
1087
1088 const TypeInt *r1 = t1->is_int(); // Handy access
1089 const TypeInt *r2 = t2->is_int(); // Handy access
1090
1091 // If the shift is a constant, just shift the bounds of the type.
1092 // For example, if the shift is 31, we just propagate sign bits.
1093 if (r2->is_con()) {
1094 uint shift = r2->get_con();
1095 shift &= BitsPerJavaInteger-1; // semantics of Java shifts
1096 // Shift by a multiple of 32 does nothing:
1097 if (shift == 0) return t1;
1098 // Calculate reasonably aggressive bounds for the result.
1099 // This is necessary if we are to correctly type things
1100 // like (x<<24>>24) == ((byte)x).
1101 jint lo = (jint)r1->_lo >> (jint)shift;
1102 jint hi = (jint)r1->_hi >> (jint)shift;
1103 assert(lo <= hi, "must have valid bounds");
1104 const TypeInt* ti = TypeInt::make(lo, hi, MAX2(r1->_widen,r2->_widen));
1105 #ifdef ASSERT
1106 // Make sure we get the sign-capture idiom correct.
1107 if (shift == BitsPerJavaInteger-1) {
1108 if (r1->_lo >= 0) assert(ti == TypeInt::ZERO, ">>31 of + is 0");
1109 if (r1->_hi < 0) assert(ti == TypeInt::MINUS_1, ">>31 of - is -1");
1110 }
1111 #endif
1112 return ti;
1113 }
1114
1115 if( !r1->is_con() || !r2->is_con() )
1116 return TypeInt::INT;
1117
1118 // Signed shift right
1119 return TypeInt::make( r1->get_con() >> (r2->get_con()&31) );
1120 }
1121
1122 //=============================================================================
1123 //------------------------------Identity---------------------------------------
1124 Node* RShiftLNode::Identity(PhaseGVN* phase) {
1125 const TypeInt *ti = phase->type(in(2))->isa_int(); // Shift count is an int.
1126 return (ti && ti->is_con() && (ti->get_con() & (BitsPerJavaLong - 1)) == 0) ? in(1) : this;
1127 }
1128
1129 //------------------------------Value------------------------------------------
1130 // A RShiftLNode shifts its input2 right by input1 amount.
1131 const Type* RShiftLNode::Value(PhaseGVN* phase) const {
1132 const Type *t1 = phase->type( in(1) );
1133 const Type *t2 = phase->type( in(2) );
1134 // Either input is TOP ==> the result is TOP
1135 if( t1 == Type::TOP ) return Type::TOP;
1136 if( t2 == Type::TOP ) return Type::TOP;
1137
1138 // Left input is ZERO ==> the result is ZERO.
1139 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
1140 // Shift by zero does nothing
1141 if( t2 == TypeInt::ZERO ) return t1;
1142
1143 // Either input is BOTTOM ==> the result is BOTTOM
1144 if (t1 == Type::BOTTOM || t2 == Type::BOTTOM)
1145 return TypeLong::LONG;
1146
1147 if (t2 == TypeInt::INT)
1148 return TypeLong::LONG;
1149
1150 const TypeLong *r1 = t1->is_long(); // Handy access
1151 const TypeInt *r2 = t2->is_int (); // Handy access
1152
1153 // If the shift is a constant, just shift the bounds of the type.
1154 // For example, if the shift is 63, we just propagate sign bits.
1155 if (r2->is_con()) {
1156 uint shift = r2->get_con();
1157 shift &= (2*BitsPerJavaInteger)-1; // semantics of Java shifts
1158 // Shift by a multiple of 64 does nothing:
1159 if (shift == 0) return t1;
1160 // Calculate reasonably aggressive bounds for the result.
1161 // This is necessary if we are to correctly type things
1162 // like (x<<24>>24) == ((byte)x).
1163 jlong lo = (jlong)r1->_lo >> (jlong)shift;
1164 jlong hi = (jlong)r1->_hi >> (jlong)shift;
1165 assert(lo <= hi, "must have valid bounds");
1166 const TypeLong* tl = TypeLong::make(lo, hi, MAX2(r1->_widen,r2->_widen));
1167 #ifdef ASSERT
1168 // Make sure we get the sign-capture idiom correct.
1169 if (shift == (2*BitsPerJavaInteger)-1) {
1170 if (r1->_lo >= 0) assert(tl == TypeLong::ZERO, ">>63 of + is 0");
1171 if (r1->_hi < 0) assert(tl == TypeLong::MINUS_1, ">>63 of - is -1");
1172 }
1173 #endif
1174 return tl;
1175 }
1176
1177 return TypeLong::LONG; // Give up
1178 }
1179
1180 //=============================================================================
1181 //------------------------------Identity---------------------------------------
1182 Node* URShiftINode::Identity(PhaseGVN* phase) {
1183 int count = 0;
1184 if (const_shift_count(phase, this, &count) && (count & (BitsPerJavaInteger - 1)) == 0) {
1185 // Shift by a multiple of 32 does nothing
1186 return in(1);
1187 }
1188
1189 // Check for "((x << LogBytesPerWord) + (wordSize-1)) >> LogBytesPerWord" which is just "x".
1190 // Happens during new-array length computation.
1191 // Safe if 'x' is in the range [0..(max_int>>LogBytesPerWord)]
1192 Node *add = in(1);
1193 if (add->Opcode() == Op_AddI) {
1194 const TypeInt *t2 = phase->type(add->in(2))->isa_int();
1195 if (t2 && t2->is_con(wordSize - 1) &&
1196 add->in(1)->Opcode() == Op_LShiftI) {
1197 // Check that shift_counts are LogBytesPerWord.
1198 Node *lshift_count = add->in(1)->in(2);
1199 const TypeInt *t_lshift_count = phase->type(lshift_count)->isa_int();
1200 if (t_lshift_count && t_lshift_count->is_con(LogBytesPerWord) &&
1201 t_lshift_count == phase->type(in(2))) {
1202 Node *x = add->in(1)->in(1);
1203 const TypeInt *t_x = phase->type(x)->isa_int();
1204 if (t_x != NULL && 0 <= t_x->_lo && t_x->_hi <= (max_jint>>LogBytesPerWord)) {
1205 return x;
1206 }
1207 }
1208 }
1209 }
1210
1211 return (phase->type(in(2))->higher_equal(TypeInt::ZERO)) ? in(1) : this;
1212 }
1213
1214 //------------------------------Ideal------------------------------------------
1215 Node *URShiftINode::Ideal(PhaseGVN *phase, bool can_reshape) {
1216 int con = maskShiftAmount(phase, this, BitsPerJavaInteger);
1217 if (con == 0) {
1218 return NULL;
1219 }
1220
1221 // We'll be wanting the right-shift amount as a mask of that many bits
1222 const int mask = right_n_bits(BitsPerJavaInteger - con);
1223
1224 int in1_op = in(1)->Opcode();
1225
1226 // Check for ((x>>>a)>>>b) and replace with (x>>>(a+b)) when a+b < 32
1227 if( in1_op == Op_URShiftI ) {
1228 const TypeInt *t12 = phase->type( in(1)->in(2) )->isa_int();
1229 if( t12 && t12->is_con() ) { // Right input is a constant
1230 assert( in(1) != in(1)->in(1), "dead loop in URShiftINode::Ideal" );
1231 const int con2 = t12->get_con() & 31; // Shift count is always masked
1232 const int con3 = con+con2;
1233 if( con3 < 32 ) // Only merge shifts if total is < 32
1234 return new URShiftINode( in(1)->in(1), phase->intcon(con3) );
1235 }
1236 }
1237
1238 // Check for ((x << z) + Y) >>> z. Replace with x + con>>>z
1239 // The idiom for rounding to a power of 2 is "(Q+(2^z-1)) >>> z".
1240 // If Q is "X << z" the rounding is useless. Look for patterns like
1241 // ((X<<Z) + Y) >>> Z and replace with (X + Y>>>Z) & Z-mask.
1242 Node *add = in(1);
1243 const TypeInt *t2 = phase->type(in(2))->isa_int();
1244 if (in1_op == Op_AddI) {
1245 Node *lshl = add->in(1);
1246 if( lshl->Opcode() == Op_LShiftI &&
1247 phase->type(lshl->in(2)) == t2 ) {
1248 Node *y_z = phase->transform( new URShiftINode(add->in(2),in(2)) );
1249 Node *sum = phase->transform( new AddINode( lshl->in(1), y_z ) );
1250 return new AndINode( sum, phase->intcon(mask) );
1251 }
1252 }
1253
1254 // Check for (x & mask) >>> z. Replace with (x >>> z) & (mask >>> z)
1255 // This shortens the mask. Also, if we are extracting a high byte and
1256 // storing it to a buffer, the mask will be removed completely.
1257 Node *andi = in(1);
1258 if( in1_op == Op_AndI ) {
1259 const TypeInt *t3 = phase->type( andi->in(2) )->isa_int();
1260 if( t3 && t3->is_con() ) { // Right input is a constant
1261 jint mask2 = t3->get_con();
1262 mask2 >>= con; // *signed* shift downward (high-order zeroes do not help)
1263 Node *newshr = phase->transform( new URShiftINode(andi->in(1), in(2)) );
1264 return new AndINode(newshr, phase->intcon(mask2));
1265 // The negative values are easier to materialize than positive ones.
1266 // A typical case from address arithmetic is ((x & ~15) >> 4).
1267 // It's better to change that to ((x >> 4) & ~0) versus
1268 // ((x >> 4) & 0x0FFFFFFF). The difference is greatest in LP64.
1269 }
1270 }
1271
1272 // Check for "(X << z ) >>> z" which simply zero-extends
1273 Node *shl = in(1);
1274 if( in1_op == Op_LShiftI &&
1275 phase->type(shl->in(2)) == t2 )
1276 return new AndINode( shl->in(1), phase->intcon(mask) );
1277
1278 // Check for (x >> n) >>> 31. Replace with (x >>> 31)
1279 Node *shr = in(1);
1280 if ( in1_op == Op_RShiftI ) {
1281 Node *in11 = shr->in(1);
1282 Node *in12 = shr->in(2);
1283 const TypeInt *t11 = phase->type(in11)->isa_int();
1284 const TypeInt *t12 = phase->type(in12)->isa_int();
1285 if ( t11 && t2 && t2->is_con(31) && t12 && t12->is_con() ) {
1286 return new URShiftINode(in11, phase->intcon(31));
1287 }
1288 }
1289
1290 return NULL;
1291 }
1292
1293 //------------------------------Value------------------------------------------
1294 // A URShiftINode shifts its input2 right by input1 amount.
1295 const Type* URShiftINode::Value(PhaseGVN* phase) const {
1296 // (This is a near clone of RShiftINode::Value.)
1297 const Type *t1 = phase->type( in(1) );
1298 const Type *t2 = phase->type( in(2) );
1299 // Either input is TOP ==> the result is TOP
1300 if( t1 == Type::TOP ) return Type::TOP;
1301 if( t2 == Type::TOP ) return Type::TOP;
1302
1303 // Left input is ZERO ==> the result is ZERO.
1304 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
1305 // Shift by zero does nothing
1306 if( t2 == TypeInt::ZERO ) return t1;
1307
1308 // Either input is BOTTOM ==> the result is BOTTOM
1309 if (t1 == Type::BOTTOM || t2 == Type::BOTTOM)
1310 return TypeInt::INT;
1311
1312 if (t2 == TypeInt::INT)
1313 return TypeInt::INT;
1314
1315 const TypeInt *r1 = t1->is_int(); // Handy access
1316 const TypeInt *r2 = t2->is_int(); // Handy access
1317
1318 if (r2->is_con()) {
1319 uint shift = r2->get_con();
1320 shift &= BitsPerJavaInteger-1; // semantics of Java shifts
1321 // Shift by a multiple of 32 does nothing:
1322 if (shift == 0) return t1;
1323 // Calculate reasonably aggressive bounds for the result.
1324 jint lo = (juint)r1->_lo >> (juint)shift;
1325 jint hi = (juint)r1->_hi >> (juint)shift;
1326 if (r1->_hi >= 0 && r1->_lo < 0) {
1327 // If the type has both negative and positive values,
1328 // there are two separate sub-domains to worry about:
1329 // The positive half and the negative half.
1330 jint neg_lo = lo;
1331 jint neg_hi = (juint)-1 >> (juint)shift;
1332 jint pos_lo = (juint) 0 >> (juint)shift;
1333 jint pos_hi = hi;
1334 lo = MIN2(neg_lo, pos_lo); // == 0
1335 hi = MAX2(neg_hi, pos_hi); // == -1 >>> shift;
1336 }
1337 assert(lo <= hi, "must have valid bounds");
1338 const TypeInt* ti = TypeInt::make(lo, hi, MAX2(r1->_widen,r2->_widen));
1339 #ifdef ASSERT
1340 // Make sure we get the sign-capture idiom correct.
1341 if (shift == BitsPerJavaInteger-1) {
1342 if (r1->_lo >= 0) assert(ti == TypeInt::ZERO, ">>>31 of + is 0");
1343 if (r1->_hi < 0) assert(ti == TypeInt::ONE, ">>>31 of - is +1");
1344 }
1345 #endif
1346 return ti;
1347 }
1348
1349 //
1350 // Do not support shifted oops in info for GC
1351 //
1352 // else if( t1->base() == Type::InstPtr ) {
1353 //
1354 // const TypeInstPtr *o = t1->is_instptr();
1355 // if( t1->singleton() )
1356 // return TypeInt::make( ((uint32_t)o->const_oop() + o->_offset) >> shift );
1357 // }
1358 // else if( t1->base() == Type::KlassPtr ) {
1359 // const TypeKlassPtr *o = t1->is_klassptr();
1360 // if( t1->singleton() )
1361 // return TypeInt::make( ((uint32_t)o->const_oop() + o->_offset) >> shift );
1362 // }
1363
1364 return TypeInt::INT;
1365 }
1366
1367 //=============================================================================
1368 //------------------------------Identity---------------------------------------
1369 Node* URShiftLNode::Identity(PhaseGVN* phase) {
1370 int count = 0;
1371 if (const_shift_count(phase, this, &count) && (count & (BitsPerJavaLong - 1)) == 0) {
1372 // Shift by a multiple of 64 does nothing
1373 return in(1);
1374 }
1375 return this;
1376 }
1377
1378 //------------------------------Ideal------------------------------------------
1379 Node *URShiftLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1380 int con = maskShiftAmount(phase, this, BitsPerJavaLong);
1381 if (con == 0) {
1382 return NULL;
1383 }
1384
1385 // We'll be wanting the right-shift amount as a mask of that many bits
1386 const jlong mask = jlong(max_julong >> con);
1387
1388 // Check for ((x << z) + Y) >>> z. Replace with x + con>>>z
1389 // The idiom for rounding to a power of 2 is "(Q+(2^z-1)) >>> z".
1390 // If Q is "X << z" the rounding is useless. Look for patterns like
1391 // ((X<<Z) + Y) >>> Z and replace with (X + Y>>>Z) & Z-mask.
1392 Node *add = in(1);
1393 const TypeInt *t2 = phase->type(in(2))->isa_int();
1394 if (add->Opcode() == Op_AddL) {
1395 Node *lshl = add->in(1);
1396 if( lshl->Opcode() == Op_LShiftL &&
1397 phase->type(lshl->in(2)) == t2 ) {
1398 Node *y_z = phase->transform( new URShiftLNode(add->in(2),in(2)) );
1399 Node *sum = phase->transform( new AddLNode( lshl->in(1), y_z ) );
1400 return new AndLNode( sum, phase->longcon(mask) );
1401 }
1402 }
1403
1404 // Check for (x & mask) >>> z. Replace with (x >>> z) & (mask >>> z)
1405 // This shortens the mask. Also, if we are extracting a high byte and
1406 // storing it to a buffer, the mask will be removed completely.
1407 Node *andi = in(1);
1408 if( andi->Opcode() == Op_AndL ) {
1409 const TypeLong *t3 = phase->type( andi->in(2) )->isa_long();
1410 if( t3 && t3->is_con() ) { // Right input is a constant
1411 jlong mask2 = t3->get_con();
1412 mask2 >>= con; // *signed* shift downward (high-order zeroes do not help)
1413 Node *newshr = phase->transform( new URShiftLNode(andi->in(1), in(2)) );
1414 return new AndLNode(newshr, phase->longcon(mask2));
1415 }
1416 }
1417
1418 // Check for "(X << z ) >>> z" which simply zero-extends
1419 Node *shl = in(1);
1420 if( shl->Opcode() == Op_LShiftL &&
1421 phase->type(shl->in(2)) == t2 )
1422 return new AndLNode( shl->in(1), phase->longcon(mask) );
1423
1424 // Check for (x >> n) >>> 63. Replace with (x >>> 63)
1425 Node *shr = in(1);
1426 if ( shr->Opcode() == Op_RShiftL ) {
1427 Node *in11 = shr->in(1);
1428 Node *in12 = shr->in(2);
1429 const TypeLong *t11 = phase->type(in11)->isa_long();
1430 const TypeInt *t12 = phase->type(in12)->isa_int();
1431 if ( t11 && t2 && t2->is_con(63) && t12 && t12->is_con() ) {
1432 return new URShiftLNode(in11, phase->intcon(63));
1433 }
1434 }
1435 return NULL;
1436 }
1437
1438 //------------------------------Value------------------------------------------
1439 // A URShiftINode shifts its input2 right by input1 amount.
1440 const Type* URShiftLNode::Value(PhaseGVN* phase) const {
1441 // (This is a near clone of RShiftLNode::Value.)
1442 const Type *t1 = phase->type( in(1) );
1443 const Type *t2 = phase->type( in(2) );
1444 // Either input is TOP ==> the result is TOP
1445 if( t1 == Type::TOP ) return Type::TOP;
1446 if( t2 == Type::TOP ) return Type::TOP;
1447
1448 // Left input is ZERO ==> the result is ZERO.
1449 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
1450 // Shift by zero does nothing
1451 if( t2 == TypeInt::ZERO ) return t1;
1452
1453 // Either input is BOTTOM ==> the result is BOTTOM
1454 if (t1 == Type::BOTTOM || t2 == Type::BOTTOM)
1455 return TypeLong::LONG;
1456
1457 if (t2 == TypeInt::INT)
1458 return TypeLong::LONG;
1459
1460 const TypeLong *r1 = t1->is_long(); // Handy access
1461 const TypeInt *r2 = t2->is_int (); // Handy access
1462
1463 if (r2->is_con()) {
1464 uint shift = r2->get_con();
1465 shift &= BitsPerJavaLong - 1; // semantics of Java shifts
1466 // Shift by a multiple of 64 does nothing:
1467 if (shift == 0) return t1;
1468 // Calculate reasonably aggressive bounds for the result.
1469 jlong lo = (julong)r1->_lo >> (juint)shift;
1470 jlong hi = (julong)r1->_hi >> (juint)shift;
1471 if (r1->_hi >= 0 && r1->_lo < 0) {
1472 // If the type has both negative and positive values,
1473 // there are two separate sub-domains to worry about:
1474 // The positive half and the negative half.
1475 jlong neg_lo = lo;
1476 jlong neg_hi = (julong)-1 >> (juint)shift;
1477 jlong pos_lo = (julong) 0 >> (juint)shift;
1478 jlong pos_hi = hi;
1479 //lo = MIN2(neg_lo, pos_lo); // == 0
1480 lo = neg_lo < pos_lo ? neg_lo : pos_lo;
1481 //hi = MAX2(neg_hi, pos_hi); // == -1 >>> shift;
1482 hi = neg_hi > pos_hi ? neg_hi : pos_hi;
1483 }
1484 assert(lo <= hi, "must have valid bounds");
1485 const TypeLong* tl = TypeLong::make(lo, hi, MAX2(r1->_widen,r2->_widen));
1486 #ifdef ASSERT
1487 // Make sure we get the sign-capture idiom correct.
1488 if (shift == BitsPerJavaLong - 1) {
1489 if (r1->_lo >= 0) assert(tl == TypeLong::ZERO, ">>>63 of + is 0");
1490 if (r1->_hi < 0) assert(tl == TypeLong::ONE, ">>>63 of - is +1");
1491 }
1492 #endif
1493 return tl;
1494 }
1495
1496 return TypeLong::LONG; // Give up
1497 }
1498
1499 //=============================================================================
1500 //------------------------------Value------------------------------------------
1501 const Type* FmaDNode::Value(PhaseGVN* phase) const {
1502 const Type *t1 = phase->type(in(1));
1503 if (t1 == Type::TOP) return Type::TOP;
1504 if (t1->base() != Type::DoubleCon) return Type::DOUBLE;
1505 const Type *t2 = phase->type(in(2));
1506 if (t2 == Type::TOP) return Type::TOP;
1507 if (t2->base() != Type::DoubleCon) return Type::DOUBLE;
1508 const Type *t3 = phase->type(in(3));
1509 if (t3 == Type::TOP) return Type::TOP;
1510 if (t3->base() != Type::DoubleCon) return Type::DOUBLE;
1511 #ifndef __STDC_IEC_559__
1512 return Type::DOUBLE;
1513 #else
1514 double d1 = t1->getd();
1515 double d2 = t2->getd();
1516 double d3 = t3->getd();
1517 return TypeD::make(fma(d1, d2, d3));
1518 #endif
1519 }
1520
1521 //=============================================================================
1522 //------------------------------Value------------------------------------------
1523 const Type* FmaFNode::Value(PhaseGVN* phase) const {
1524 const Type *t1 = phase->type(in(1));
1525 if (t1 == Type::TOP) return Type::TOP;
1526 if (t1->base() != Type::FloatCon) return Type::FLOAT;
1527 const Type *t2 = phase->type(in(2));
1528 if (t2 == Type::TOP) return Type::TOP;
1529 if (t2->base() != Type::FloatCon) return Type::FLOAT;
1530 const Type *t3 = phase->type(in(3));
1531 if (t3 == Type::TOP) return Type::TOP;
1532 if (t3->base() != Type::FloatCon) return Type::FLOAT;
1533 #ifndef __STDC_IEC_559__
1534 return Type::FLOAT;
1535 #else
1536 float f1 = t1->getf();
1537 float f2 = t2->getf();
1538 float f3 = t3->getf();
1539 return TypeF::make(fma(f1, f2, f3));
1540 #endif
1541 }
1542
1543 //=============================================================================
1544 //------------------------------hash-------------------------------------------
1545 // Hash function for MulAddS2INode. Operation is commutative with commutative pairs.
1546 // The hash function must return the same value when edge swapping is performed.
1547 uint MulAddS2INode::hash() const {
1548 return (uintptr_t)in(1) + (uintptr_t)in(2) + (uintptr_t)in(3) + (uintptr_t)in(4) + Opcode();
1549 }
1550
1551 //------------------------------Rotate Operations ------------------------------
1552
1553 Node* RotateLeftNode::Identity(PhaseGVN* phase) {
1554 const Type* t1 = phase->type(in(1));
1555 if (t1 == Type::TOP) {
1556 return this;
1557 }
1558 int count = 0;
1559 assert(t1->isa_int() || t1->isa_long(), "Unexpected type");
1560 int mask = (t1->isa_int() ? BitsPerJavaInteger : BitsPerJavaLong) - 1;
1561 if (const_shift_count(phase, this, &count) && (count & mask) == 0) {
1562 // Rotate by a multiple of 32/64 does nothing
1563 return in(1);
1564 }
1565 return this;
1566 }
1567
1568 const Type* RotateLeftNode::Value(PhaseGVN* phase) const {
1569 const Type* t1 = phase->type(in(1));
1570 const Type* t2 = phase->type(in(2));
1571 // Either input is TOP ==> the result is TOP
1572 if (t1 == Type::TOP || t2 == Type::TOP) {
1573 return Type::TOP;
1574 }
1575
1576 if (t1->isa_int()) {
1577 const TypeInt* r1 = t1->is_int();
1578 const TypeInt* r2 = t2->is_int();
1579
1580 // Left input is ZERO ==> the result is ZERO.
1581 if (r1 == TypeInt::ZERO) {
1582 return TypeInt::ZERO;
1583 }
1584 // Rotate by zero does nothing
1585 if (r2 == TypeInt::ZERO) {
1586 return r1;
1587 }
1588 if (r1->is_con() && r2->is_con()) {
1589 juint r1_con = (juint)r1->get_con();
1590 juint shift = (juint)(r2->get_con()) & (juint)(BitsPerJavaInteger - 1); // semantics of Java shifts
1591 return TypeInt::make((r1_con << shift) | (r1_con >> (32 - shift)));
1592 }
1593 return TypeInt::INT;
1594 } else {
1595 assert(t1->isa_long(), "Type must be a long");
1596 const TypeLong* r1 = t1->is_long();
1597 const TypeInt* r2 = t2->is_int();
1598
1599 // Left input is ZERO ==> the result is ZERO.
1600 if (r1 == TypeLong::ZERO) {
1601 return TypeLong::ZERO;
1602 }
1603 // Rotate by zero does nothing
1604 if (r2 == TypeInt::ZERO) {
1605 return r1;
1606 }
1607 if (r1->is_con() && r2->is_con()) {
1608 julong r1_con = (julong)r1->get_con();
1609 julong shift = (julong)(r2->get_con()) & (julong)(BitsPerJavaLong - 1); // semantics of Java shifts
1610 return TypeLong::make((r1_con << shift) | (r1_con >> (64 - shift)));
1611 }
1612 return TypeLong::LONG;
1613 }
1614 }
1615
1616 Node* RotateLeftNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1617 const Type* t1 = phase->type(in(1));
1618 const Type* t2 = phase->type(in(2));
1619 if (t2->isa_int() && t2->is_int()->is_con()) {
1620 if (t1->isa_int()) {
1621 int lshift = t2->is_int()->get_con() & 31;
1622 return new RotateRightNode(in(1), phase->intcon(32 - (lshift & 31)), TypeInt::INT);
1623 } else if (t1 != Type::TOP) {
1624 assert(t1->isa_long(), "Type must be a long");
1625 int lshift = t2->is_int()->get_con() & 63;
1626 return new RotateRightNode(in(1), phase->intcon(64 - (lshift & 63)), TypeLong::LONG);
1627 }
1628 }
1629 return NULL;
1630 }
1631
1632 Node* RotateRightNode::Identity(PhaseGVN* phase) {
1633 const Type* t1 = phase->type(in(1));
1634 if (t1 == Type::TOP) {
1635 return this;
1636 }
1637 int count = 0;
1638 assert(t1->isa_int() || t1->isa_long(), "Unexpected type");
1639 int mask = (t1->isa_int() ? BitsPerJavaInteger : BitsPerJavaLong) - 1;
1640 if (const_shift_count(phase, this, &count) && (count & mask) == 0) {
1641 // Rotate by a multiple of 32/64 does nothing
1642 return in(1);
1643 }
1644 return this;
1645 }
1646
1647 const Type* RotateRightNode::Value(PhaseGVN* phase) const {
1648 const Type* t1 = phase->type(in(1));
1649 const Type* t2 = phase->type(in(2));
1650 // Either input is TOP ==> the result is TOP
1651 if (t1 == Type::TOP || t2 == Type::TOP) {
1652 return Type::TOP;
1653 }
1654
1655 if (t1->isa_int()) {
1656 const TypeInt* r1 = t1->is_int();
1657 const TypeInt* r2 = t2->is_int();
1658
1659 // Left input is ZERO ==> the result is ZERO.
1660 if (r1 == TypeInt::ZERO) {
1661 return TypeInt::ZERO;
1662 }
1663 // Rotate by zero does nothing
1664 if (r2 == TypeInt::ZERO) {
1665 return r1;
1666 }
1667 if (r1->is_con() && r2->is_con()) {
1668 juint r1_con = (juint)r1->get_con();
1669 juint shift = (juint)(r2->get_con()) & (juint)(BitsPerJavaInteger - 1); // semantics of Java shifts
1670 return TypeInt::make((r1_con >> shift) | (r1_con << (32 - shift)));
1671 }
1672 return TypeInt::INT;
1673 } else {
1674 assert(t1->isa_long(), "Type must be a long");
1675 const TypeLong* r1 = t1->is_long();
1676 const TypeInt* r2 = t2->is_int();
1677 // Left input is ZERO ==> the result is ZERO.
1678 if (r1 == TypeLong::ZERO) {
1679 return TypeLong::ZERO;
1680 }
1681 // Rotate by zero does nothing
1682 if (r2 == TypeInt::ZERO) {
1683 return r1;
1684 }
1685 if (r1->is_con() && r2->is_con()) {
1686 julong r1_con = (julong)r1->get_con();
1687 julong shift = (julong)(r2->get_con()) & (julong)(BitsPerJavaLong - 1); // semantics of Java shifts
1688 return TypeLong::make((r1_con >> shift) | (r1_con << (64 - shift)));
1689 }
1690 return TypeLong::LONG;
1691 }
1692 }