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 // Either input is TOP ==> the result is TOP
448 const Type *t1 = phase->type( in(1) );
449 const Type *t2 = phase->type( in(2) );
450 if( t1 == Type::TOP ) return Type::TOP;
451 if( t2 == Type::TOP ) return Type::TOP;
452
453 // Either input is BOTTOM ==> the result is the local BOTTOM
454 const Type *bot = bottom_type();
455 if( (t1 == bot) || (t2 == bot) ||
456 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
457 return bot;
458
459 // It is not worth trying to constant fold this stuff!
460 return TypeLong::LONG;
461 }
462
463 //=============================================================================
464 //------------------------------mul_ring---------------------------------------
465 // Supplied function returns the product of the inputs IN THE CURRENT RING.
466 // For the logical operations the ring's MUL is really a logical AND function.
467 // This also type-checks the inputs for sanity. Guaranteed never to
468 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
469 const Type *AndINode::mul_ring( const Type *t0, const Type *t1 ) const {
470 const TypeInt *r0 = t0->is_int(); // Handy access
471 const TypeInt *r1 = t1->is_int();
472 int widen = MAX2(r0->_widen,r1->_widen);
473
474 // If either input is a constant, might be able to trim cases
475 if( !r0->is_con() && !r1->is_con() )
476 return TypeInt::INT; // No constants to be had
477
478 // Both constants? Return bits
479 if( r0->is_con() && r1->is_con() )
480 return TypeInt::make( r0->get_con() & r1->get_con() );
481
482 if( r0->is_con() && r0->get_con() > 0 )
483 return TypeInt::make(0, r0->get_con(), widen);
484
485 if( r1->is_con() && r1->get_con() > 0 )
486 return TypeInt::make(0, r1->get_con(), widen);
487
488 if( r0 == TypeInt::BOOL || r1 == TypeInt::BOOL ) {
489 return TypeInt::BOOL;
490 }
491
492 return TypeInt::INT; // No constants to be had
493 }
494
495 //------------------------------Identity---------------------------------------
496 // Masking off the high bits of an unsigned load is not required
497 Node* AndINode::Identity(PhaseGVN* phase) {
498
499 // x & x => x
500 if (in(1) == in(2)) {
501 return in(1);
502 }
503
504 Node* in1 = in(1);
505 uint op = in1->Opcode();
506 const TypeInt* t2 = phase->type(in(2))->isa_int();
507 if (t2 && t2->is_con()) {
508 int con = t2->get_con();
509 // Masking off high bits which are always zero is useless.
510 const TypeInt* t1 = phase->type(in(1))->isa_int();
511 if (t1 != NULL && t1->_lo >= 0) {
512 jint t1_support = right_n_bits(1 + log2i_graceful(t1->_hi));
513 if ((t1_support & con) == t1_support)
514 return in1;
515 }
516 // Masking off the high bits of a unsigned-shift-right is not
517 // needed either.
518 if (op == Op_URShiftI) {
519 const TypeInt* t12 = phase->type(in1->in(2))->isa_int();
520 if (t12 && t12->is_con()) { // Shift is by a constant
521 int shift = t12->get_con();
522 shift &= BitsPerJavaInteger - 1; // semantics of Java shifts
523 int mask = max_juint >> shift;
524 if ((mask & con) == mask) // If AND is useless, skip it
525 return in1;
526 }
527 }
528 }
529 return MulNode::Identity(phase);
530 }
531
532 //------------------------------Ideal------------------------------------------
533 Node *AndINode::Ideal(PhaseGVN *phase, bool can_reshape) {
534 // Special case constant AND mask
535 const TypeInt *t2 = phase->type( in(2) )->isa_int();
536 if( !t2 || !t2->is_con() ) return MulNode::Ideal(phase, can_reshape);
537 const int mask = t2->get_con();
538 Node *load = in(1);
539 uint lop = load->Opcode();
540
541 // Masking bits off of a Character? Hi bits are already zero.
542 if( lop == Op_LoadUS &&
543 (mask & 0xFFFF0000) ) // Can we make a smaller mask?
544 return new AndINode(load,phase->intcon(mask&0xFFFF));
545
546 // Masking bits off of a Short? Loading a Character does some masking
547 if (can_reshape &&
548 load->outcnt() == 1 && load->unique_out() == this) {
549 if (lop == Op_LoadS && (mask & 0xFFFF0000) == 0 ) {
550 Node* ldus = load->as_Load()->convert_to_unsigned_load(*phase);
551 ldus = phase->transform(ldus);
552 return new AndINode(ldus, phase->intcon(mask & 0xFFFF));
553 }
554
555 // Masking sign bits off of a Byte? Do an unsigned byte load plus
556 // an and.
557 if (lop == Op_LoadB && (mask & 0xFFFFFF00) == 0) {
558 Node* ldub = load->as_Load()->convert_to_unsigned_load(*phase);
559 ldub = phase->transform(ldub);
560 return new AndINode(ldub, phase->intcon(mask));
561 }
562 }
563
564 // Masking off sign bits? Dont make them!
565 if( lop == Op_RShiftI ) {
566 const TypeInt *t12 = phase->type(load->in(2))->isa_int();
567 if( t12 && t12->is_con() ) { // Shift is by a constant
568 int shift = t12->get_con();
569 shift &= BitsPerJavaInteger-1; // semantics of Java shifts
570 const int sign_bits_mask = ~right_n_bits(BitsPerJavaInteger - shift);
571 // If the AND'ing of the 2 masks has no bits, then only original shifted
572 // bits survive. NO sign-extension bits survive the maskings.
573 if( (sign_bits_mask & mask) == 0 ) {
574 // Use zero-fill shift instead
575 Node *zshift = phase->transform(new URShiftINode(load->in(1),load->in(2)));
576 return new AndINode( zshift, in(2) );
577 }
578 }
579 }
580
581 // Check for 'negate/and-1', a pattern emitted when someone asks for
582 // 'mod 2'. Negate leaves the low order bit unchanged (think: complement
583 // plus 1) and the mask is of the low order bit. Skip the negate.
584 if( lop == Op_SubI && mask == 1 && load->in(1) &&
585 phase->type(load->in(1)) == TypeInt::ZERO )
586 return new AndINode( load->in(2), in(2) );
587
588 return MulNode::Ideal(phase, can_reshape);
589 }
590
591 //=============================================================================
592 //------------------------------mul_ring---------------------------------------
593 // Supplied function returns the product of the inputs IN THE CURRENT RING.
594 // For the logical operations the ring's MUL is really a logical AND function.
595 // This also type-checks the inputs for sanity. Guaranteed never to
596 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
597 const Type *AndLNode::mul_ring( const Type *t0, const Type *t1 ) const {
598 const TypeLong *r0 = t0->is_long(); // Handy access
599 const TypeLong *r1 = t1->is_long();
600 int widen = MAX2(r0->_widen,r1->_widen);
601
602 // If either input is a constant, might be able to trim cases
603 if( !r0->is_con() && !r1->is_con() )
604 return TypeLong::LONG; // No constants to be had
605
606 // Both constants? Return bits
607 if( r0->is_con() && r1->is_con() )
608 return TypeLong::make( r0->get_con() & r1->get_con() );
609
610 if( r0->is_con() && r0->get_con() > 0 )
611 return TypeLong::make(CONST64(0), r0->get_con(), widen);
612
613 if( r1->is_con() && r1->get_con() > 0 )
614 return TypeLong::make(CONST64(0), r1->get_con(), widen);
615
616 return TypeLong::LONG; // No constants to be had
617 }
618
619 //------------------------------Identity---------------------------------------
620 // Masking off the high bits of an unsigned load is not required
621 Node* AndLNode::Identity(PhaseGVN* phase) {
622
623 // x & x => x
624 if (in(1) == in(2)) {
625 return in(1);
626 }
627
628 Node *usr = in(1);
629 const TypeLong *t2 = phase->type( in(2) )->isa_long();
630 if( t2 && t2->is_con() ) {
631 jlong con = t2->get_con();
632 // Masking off high bits which are always zero is useless.
633 const TypeLong* t1 = phase->type( in(1) )->isa_long();
634 if (t1 != NULL && t1->_lo >= 0) {
635 int bit_count = log2i_graceful(t1->_hi) + 1;
636 jlong t1_support = jlong(max_julong >> (BitsPerJavaLong - bit_count));
637 if ((t1_support & con) == t1_support)
638 return usr;
639 }
640 uint lop = usr->Opcode();
641 // Masking off the high bits of a unsigned-shift-right is not
642 // needed either.
643 if( lop == Op_URShiftL ) {
644 const TypeInt *t12 = phase->type( usr->in(2) )->isa_int();
645 if( t12 && t12->is_con() ) { // Shift is by a constant
646 int shift = t12->get_con();
647 shift &= BitsPerJavaLong - 1; // semantics of Java shifts
648 jlong mask = max_julong >> shift;
649 if( (mask&con) == mask ) // If AND is useless, skip it
650 return usr;
651 }
652 }
653
654 // Check if this is part of an inline type test
655 if (con == markWord::inline_type_pattern && in(1)->is_Load() &&
656 phase->type(in(1)->in(MemNode::Address))->is_inlinetypeptr() &&
657 phase->type(in(1)->in(MemNode::Address))->is_ptr()->offset() == oopDesc::mark_offset_in_bytes()) {
658 assert(EnableValhalla, "should only be used for inline types");
659 return in(2); // Obj is known to be an inline type
660 }
661 }
662 return MulNode::Identity(phase);
663 }
664
665 //------------------------------Ideal------------------------------------------
666 Node *AndLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
667 // Special case constant AND mask
668 const TypeLong *t2 = phase->type( in(2) )->isa_long();
669 if( !t2 || !t2->is_con() ) return MulNode::Ideal(phase, can_reshape);
670 const jlong mask = t2->get_con();
671
672 Node* in1 = in(1);
673 uint op = in1->Opcode();
674
675 // Are we masking a long that was converted from an int with a mask
676 // that fits in 32-bits? Commute them and use an AndINode. Don't
677 // convert masks which would cause a sign extension of the integer
678 // value. This check includes UI2L masks (0x00000000FFFFFFFF) which
679 // would be optimized away later in Identity.
680 if (op == Op_ConvI2L && (mask & UCONST64(0xFFFFFFFF80000000)) == 0) {
681 Node* andi = new AndINode(in1->in(1), phase->intcon(mask));
682 andi = phase->transform(andi);
683 return new ConvI2LNode(andi);
684 }
685
686 // Masking off sign bits? Dont make them!
687 if (op == Op_RShiftL) {
688 const TypeInt* t12 = phase->type(in1->in(2))->isa_int();
689 if( t12 && t12->is_con() ) { // Shift is by a constant
690 int shift = t12->get_con();
691 shift &= BitsPerJavaLong - 1; // semantics of Java shifts
692 const jlong sign_bits_mask = ~(((jlong)CONST64(1) << (jlong)(BitsPerJavaLong - shift)) -1);
693 // If the AND'ing of the 2 masks has no bits, then only original shifted
694 // bits survive. NO sign-extension bits survive the maskings.
695 if( (sign_bits_mask & mask) == 0 ) {
696 // Use zero-fill shift instead
697 Node *zshift = phase->transform(new URShiftLNode(in1->in(1), in1->in(2)));
698 return new AndLNode(zshift, in(2));
699 }
700 }
701 }
702
703 return MulNode::Ideal(phase, can_reshape);
704 }
705
706 //=============================================================================
707
708 static bool const_shift_count(PhaseGVN* phase, Node* shiftNode, int* count) {
709 const TypeInt* tcount = phase->type(shiftNode->in(2))->isa_int();
710 if (tcount != NULL && tcount->is_con()) {
711 *count = tcount->get_con();
712 return true;
713 }
714 return false;
715 }
716
717 static int maskShiftAmount(PhaseGVN* phase, Node* shiftNode, int nBits) {
718 int count = 0;
719 if (const_shift_count(phase, shiftNode, &count)) {
720 int maskedShift = count & (nBits - 1);
721 if (maskedShift == 0) {
722 // Let Identity() handle 0 shift count.
723 return 0;
724 }
725
726 if (count != maskedShift) {
727 shiftNode->set_req(2, phase->intcon(maskedShift)); // Replace shift count with masked value.
728 PhaseIterGVN* igvn = phase->is_IterGVN();
729 if (igvn) {
730 igvn->rehash_node_delayed(shiftNode);
731 }
732 }
733 return maskedShift;
734 }
735 return 0;
736 }
737
738 //------------------------------Identity---------------------------------------
739 Node* LShiftINode::Identity(PhaseGVN* phase) {
740 int count = 0;
741 if (const_shift_count(phase, this, &count) && (count & (BitsPerJavaInteger - 1)) == 0) {
742 // Shift by a multiple of 32 does nothing
743 return in(1);
744 }
745 return this;
746 }
747
748 //------------------------------Ideal------------------------------------------
749 // If the right input is a constant, and the left input is an add of a
750 // constant, flatten the tree: (X+con1)<<con0 ==> X<<con0 + con1<<con0
751 Node *LShiftINode::Ideal(PhaseGVN *phase, bool can_reshape) {
752 int con = maskShiftAmount(phase, this, BitsPerJavaInteger);
753 if (con == 0) {
754 return NULL;
755 }
756
757 // Left input is an add of a constant?
758 Node *add1 = in(1);
759 int add1_op = add1->Opcode();
760 if( add1_op == Op_AddI ) { // Left input is an add?
761 assert( add1 != add1->in(1), "dead loop in LShiftINode::Ideal" );
762 const TypeInt *t12 = phase->type(add1->in(2))->isa_int();
763 if( t12 && t12->is_con() ){ // Left input is an add of a con?
764 // Transform is legal, but check for profit. Avoid breaking 'i2s'
765 // and 'i2b' patterns which typically fold into 'StoreC/StoreB'.
766 if( con < 16 ) {
767 // Compute X << con0
768 Node *lsh = phase->transform( new LShiftINode( add1->in(1), in(2) ) );
769 // Compute X<<con0 + (con1<<con0)
770 return new AddINode( lsh, phase->intcon(t12->get_con() << con));
771 }
772 }
773 }
774
775 // Check for "(x>>c0)<<c0" which just masks off low bits
776 if( (add1_op == Op_RShiftI || add1_op == Op_URShiftI ) &&
777 add1->in(2) == in(2) )
778 // Convert to "(x & -(1<<c0))"
779 return new AndINode(add1->in(1),phase->intcon( -(1<<con)));
780
781 // Check for "((x>>c0) & Y)<<c0" which just masks off more low bits
782 if( add1_op == Op_AndI ) {
783 Node *add2 = add1->in(1);
784 int add2_op = add2->Opcode();
785 if( (add2_op == Op_RShiftI || add2_op == Op_URShiftI ) &&
786 add2->in(2) == in(2) ) {
787 // Convert to "(x & (Y<<c0))"
788 Node *y_sh = phase->transform( new LShiftINode( add1->in(2), in(2) ) );
789 return new AndINode( add2->in(1), y_sh );
790 }
791 }
792
793 // Check for ((x & ((1<<(32-c0))-1)) << c0) which ANDs off high bits
794 // before shifting them away.
795 const jint bits_mask = right_n_bits(BitsPerJavaInteger-con);
796 if( add1_op == Op_AndI &&
797 phase->type(add1->in(2)) == TypeInt::make( bits_mask ) )
798 return new LShiftINode( add1->in(1), in(2) );
799
800 return NULL;
801 }
802
803 //------------------------------Value------------------------------------------
804 // A LShiftINode shifts its input2 left by input1 amount.
805 const Type* LShiftINode::Value(PhaseGVN* phase) const {
806 const Type *t1 = phase->type( in(1) );
807 const Type *t2 = phase->type( in(2) );
808 // Either input is TOP ==> the result is TOP
809 if( t1 == Type::TOP ) return Type::TOP;
810 if( t2 == Type::TOP ) return Type::TOP;
811
812 // Left input is ZERO ==> the result is ZERO.
813 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
814 // Shift by zero does nothing
815 if( t2 == TypeInt::ZERO ) return t1;
816
817 // Either input is BOTTOM ==> the result is BOTTOM
818 if( (t1 == TypeInt::INT) || (t2 == TypeInt::INT) ||
819 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
820 return TypeInt::INT;
821
822 const TypeInt *r1 = t1->is_int(); // Handy access
823 const TypeInt *r2 = t2->is_int(); // Handy access
824
825 if (!r2->is_con())
826 return TypeInt::INT;
827
828 uint shift = r2->get_con();
829 shift &= BitsPerJavaInteger-1; // semantics of Java shifts
830 // Shift by a multiple of 32 does nothing:
831 if (shift == 0) return t1;
832
833 // If the shift is a constant, shift the bounds of the type,
834 // unless this could lead to an overflow.
835 if (!r1->is_con()) {
836 jint lo = r1->_lo, hi = r1->_hi;
837 if (((lo << shift) >> shift) == lo &&
838 ((hi << shift) >> shift) == hi) {
839 // No overflow. The range shifts up cleanly.
840 return TypeInt::make((jint)lo << (jint)shift,
841 (jint)hi << (jint)shift,
842 MAX2(r1->_widen,r2->_widen));
843 }
844 return TypeInt::INT;
845 }
846
847 return TypeInt::make( (jint)r1->get_con() << (jint)shift );
848 }
849
850 //=============================================================================
851 //------------------------------Identity---------------------------------------
852 Node* LShiftLNode::Identity(PhaseGVN* phase) {
853 int count = 0;
854 if (const_shift_count(phase, this, &count) && (count & (BitsPerJavaLong - 1)) == 0) {
855 // Shift by a multiple of 64 does nothing
856 return in(1);
857 }
858 return this;
859 }
860
861 //------------------------------Ideal------------------------------------------
862 // If the right input is a constant, and the left input is an add of a
863 // constant, flatten the tree: (X+con1)<<con0 ==> X<<con0 + con1<<con0
864 Node *LShiftLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
865 int con = maskShiftAmount(phase, this, BitsPerJavaLong);
866 if (con == 0) {
867 return NULL;
868 }
869
870 // Left input is an add of a constant?
871 Node *add1 = in(1);
872 int add1_op = add1->Opcode();
873 if( add1_op == Op_AddL ) { // Left input is an add?
874 // Avoid dead data cycles from dead loops
875 assert( add1 != add1->in(1), "dead loop in LShiftLNode::Ideal" );
876 const TypeLong *t12 = phase->type(add1->in(2))->isa_long();
877 if( t12 && t12->is_con() ){ // Left input is an add of a con?
878 // Compute X << con0
879 Node *lsh = phase->transform( new LShiftLNode( add1->in(1), in(2) ) );
880 // Compute X<<con0 + (con1<<con0)
881 return new AddLNode( lsh, phase->longcon(t12->get_con() << con));
882 }
883 }
884
885 // Check for "(x>>c0)<<c0" which just masks off low bits
886 if( (add1_op == Op_RShiftL || add1_op == Op_URShiftL ) &&
887 add1->in(2) == in(2) )
888 // Convert to "(x & -(1<<c0))"
889 return new AndLNode(add1->in(1),phase->longcon( -(CONST64(1)<<con)));
890
891 // Check for "((x>>c0) & Y)<<c0" which just masks off more low bits
892 if( add1_op == Op_AndL ) {
893 Node *add2 = add1->in(1);
894 int add2_op = add2->Opcode();
895 if( (add2_op == Op_RShiftL || add2_op == Op_URShiftL ) &&
896 add2->in(2) == in(2) ) {
897 // Convert to "(x & (Y<<c0))"
898 Node *y_sh = phase->transform( new LShiftLNode( add1->in(2), in(2) ) );
899 return new AndLNode( add2->in(1), y_sh );
900 }
901 }
902
903 // Check for ((x & ((CONST64(1)<<(64-c0))-1)) << c0) which ANDs off high bits
904 // before shifting them away.
905 const jlong bits_mask = jlong(max_julong >> con);
906 if( add1_op == Op_AndL &&
907 phase->type(add1->in(2)) == TypeLong::make( bits_mask ) )
908 return new LShiftLNode( add1->in(1), in(2) );
909
910 return NULL;
911 }
912
913 //------------------------------Value------------------------------------------
914 // A LShiftLNode shifts its input2 left by input1 amount.
915 const Type* LShiftLNode::Value(PhaseGVN* phase) const {
916 const Type *t1 = phase->type( in(1) );
917 const Type *t2 = phase->type( in(2) );
918 // Either input is TOP ==> the result is TOP
919 if( t1 == Type::TOP ) return Type::TOP;
920 if( t2 == Type::TOP ) return Type::TOP;
921
922 // Left input is ZERO ==> the result is ZERO.
923 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
924 // Shift by zero does nothing
925 if( t2 == TypeInt::ZERO ) return t1;
926
927 // Either input is BOTTOM ==> the result is BOTTOM
928 if( (t1 == TypeLong::LONG) || (t2 == TypeInt::INT) ||
929 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
930 return TypeLong::LONG;
931
932 const TypeLong *r1 = t1->is_long(); // Handy access
933 const TypeInt *r2 = t2->is_int(); // Handy access
934
935 if (!r2->is_con())
936 return TypeLong::LONG;
937
938 uint shift = r2->get_con();
939 shift &= BitsPerJavaLong - 1; // semantics of Java shifts
940 // Shift by a multiple of 64 does nothing:
941 if (shift == 0) return t1;
942
943 // If the shift is a constant, shift the bounds of the type,
944 // unless this could lead to an overflow.
945 if (!r1->is_con()) {
946 jlong lo = r1->_lo, hi = r1->_hi;
947 if (((lo << shift) >> shift) == lo &&
948 ((hi << shift) >> shift) == hi) {
949 // No overflow. The range shifts up cleanly.
950 return TypeLong::make((jlong)lo << (jint)shift,
951 (jlong)hi << (jint)shift,
952 MAX2(r1->_widen,r2->_widen));
953 }
954 return TypeLong::LONG;
955 }
956
957 return TypeLong::make( (jlong)r1->get_con() << (jint)shift );
958 }
959
960 //=============================================================================
961 //------------------------------Identity---------------------------------------
962 Node* RShiftINode::Identity(PhaseGVN* phase) {
963 int count = 0;
964 if (const_shift_count(phase, this, &count)) {
965 if ((count & (BitsPerJavaInteger - 1)) == 0) {
966 // Shift by a multiple of 32 does nothing
967 return in(1);
968 }
969 // Check for useless sign-masking
970 if (in(1)->Opcode() == Op_LShiftI &&
971 in(1)->req() == 3 &&
972 in(1)->in(2) == in(2)) {
973 count &= BitsPerJavaInteger-1; // semantics of Java shifts
974 // Compute masks for which this shifting doesn't change
975 int lo = (-1 << (BitsPerJavaInteger - ((uint)count)-1)); // FFFF8000
976 int hi = ~lo; // 00007FFF
977 const TypeInt* t11 = phase->type(in(1)->in(1))->isa_int();
978 if (t11 == NULL) {
979 return this;
980 }
981 // Does actual value fit inside of mask?
982 if (lo <= t11->_lo && t11->_hi <= hi) {
983 return in(1)->in(1); // Then shifting is a nop
984 }
985 }
986 }
987 return this;
988 }
989
990 //------------------------------Ideal------------------------------------------
991 Node *RShiftINode::Ideal(PhaseGVN *phase, bool can_reshape) {
992 // Inputs may be TOP if they are dead.
993 const TypeInt *t1 = phase->type(in(1))->isa_int();
994 if (!t1) return NULL; // Left input is an integer
995 const TypeInt *t3; // type of in(1).in(2)
996 int shift = maskShiftAmount(phase, this, BitsPerJavaInteger);
997 if (shift == 0) {
998 return NULL;
999 }
1000
1001 // Check for (x & 0xFF000000) >> 24, whose mask can be made smaller.
1002 // Such expressions arise normally from shift chains like (byte)(x >> 24).
1003 const Node *mask = in(1);
1004 if( mask->Opcode() == Op_AndI &&
1005 (t3 = phase->type(mask->in(2))->isa_int()) &&
1006 t3->is_con() ) {
1007 Node *x = mask->in(1);
1008 jint maskbits = t3->get_con();
1009 // Convert to "(x >> shift) & (mask >> shift)"
1010 Node *shr_nomask = phase->transform( new RShiftINode(mask->in(1), in(2)) );
1011 return new AndINode(shr_nomask, phase->intcon( maskbits >> shift));
1012 }
1013
1014 // Check for "(short[i] <<16)>>16" which simply sign-extends
1015 const Node *shl = in(1);
1016 if( shl->Opcode() != Op_LShiftI ) return NULL;
1017
1018 if( shift == 16 &&
1019 (t3 = phase->type(shl->in(2))->isa_int()) &&
1020 t3->is_con(16) ) {
1021 Node *ld = shl->in(1);
1022 if( ld->Opcode() == Op_LoadS ) {
1023 // Sign extension is just useless here. Return a RShiftI of zero instead
1024 // returning 'ld' directly. We cannot return an old Node directly as
1025 // that is the job of 'Identity' calls and Identity calls only work on
1026 // direct inputs ('ld' is an extra Node removed from 'this'). The
1027 // combined optimization requires Identity only return direct inputs.
1028 set_req_X(1, ld, phase);
1029 set_req_X(2, phase->intcon(0), phase);
1030 return this;
1031 }
1032 else if (can_reshape &&
1033 ld->Opcode() == Op_LoadUS &&
1034 ld->outcnt() == 1 && ld->unique_out() == shl)
1035 // Replace zero-extension-load with sign-extension-load
1036 return ld->as_Load()->convert_to_signed_load(*phase);
1037 }
1038
1039 // Check for "(byte[i] <<24)>>24" which simply sign-extends
1040 if( shift == 24 &&
1041 (t3 = phase->type(shl->in(2))->isa_int()) &&
1042 t3->is_con(24) ) {
1043 Node *ld = shl->in(1);
1044 if (ld->Opcode() == Op_LoadB) {
1045 // Sign extension is just useless here
1046 set_req_X(1, ld, phase);
1047 set_req_X(2, phase->intcon(0), phase);
1048 return this;
1049 }
1050 }
1051
1052 return NULL;
1053 }
1054
1055 //------------------------------Value------------------------------------------
1056 // A RShiftINode shifts its input2 right by input1 amount.
1057 const Type* RShiftINode::Value(PhaseGVN* phase) const {
1058 const Type *t1 = phase->type( in(1) );
1059 const Type *t2 = phase->type( in(2) );
1060 // Either input is TOP ==> the result is TOP
1061 if( t1 == Type::TOP ) return Type::TOP;
1062 if( t2 == Type::TOP ) return Type::TOP;
1063
1064 // Left input is ZERO ==> the result is ZERO.
1065 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
1066 // Shift by zero does nothing
1067 if( t2 == TypeInt::ZERO ) return t1;
1068
1069 // Either input is BOTTOM ==> the result is BOTTOM
1070 if (t1 == Type::BOTTOM || t2 == Type::BOTTOM)
1071 return TypeInt::INT;
1072
1073 if (t2 == TypeInt::INT)
1074 return TypeInt::INT;
1075
1076 const TypeInt *r1 = t1->is_int(); // Handy access
1077 const TypeInt *r2 = t2->is_int(); // Handy access
1078
1079 // If the shift is a constant, just shift the bounds of the type.
1080 // For example, if the shift is 31, we just propagate sign bits.
1081 if (r2->is_con()) {
1082 uint shift = r2->get_con();
1083 shift &= BitsPerJavaInteger-1; // semantics of Java shifts
1084 // Shift by a multiple of 32 does nothing:
1085 if (shift == 0) return t1;
1086 // Calculate reasonably aggressive bounds for the result.
1087 // This is necessary if we are to correctly type things
1088 // like (x<<24>>24) == ((byte)x).
1089 jint lo = (jint)r1->_lo >> (jint)shift;
1090 jint hi = (jint)r1->_hi >> (jint)shift;
1091 assert(lo <= hi, "must have valid bounds");
1092 const TypeInt* ti = TypeInt::make(lo, hi, MAX2(r1->_widen,r2->_widen));
1093 #ifdef ASSERT
1094 // Make sure we get the sign-capture idiom correct.
1095 if (shift == BitsPerJavaInteger-1) {
1096 if (r1->_lo >= 0) assert(ti == TypeInt::ZERO, ">>31 of + is 0");
1097 if (r1->_hi < 0) assert(ti == TypeInt::MINUS_1, ">>31 of - is -1");
1098 }
1099 #endif
1100 return ti;
1101 }
1102
1103 if( !r1->is_con() || !r2->is_con() )
1104 return TypeInt::INT;
1105
1106 // Signed shift right
1107 return TypeInt::make( r1->get_con() >> (r2->get_con()&31) );
1108 }
1109
1110 //=============================================================================
1111 //------------------------------Identity---------------------------------------
1112 Node* RShiftLNode::Identity(PhaseGVN* phase) {
1113 const TypeInt *ti = phase->type(in(2))->isa_int(); // Shift count is an int.
1114 return (ti && ti->is_con() && (ti->get_con() & (BitsPerJavaLong - 1)) == 0) ? in(1) : this;
1115 }
1116
1117 //------------------------------Value------------------------------------------
1118 // A RShiftLNode shifts its input2 right by input1 amount.
1119 const Type* RShiftLNode::Value(PhaseGVN* phase) const {
1120 const Type *t1 = phase->type( in(1) );
1121 const Type *t2 = phase->type( in(2) );
1122 // Either input is TOP ==> the result is TOP
1123 if( t1 == Type::TOP ) return Type::TOP;
1124 if( t2 == Type::TOP ) return Type::TOP;
1125
1126 // Left input is ZERO ==> the result is ZERO.
1127 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
1128 // Shift by zero does nothing
1129 if( t2 == TypeInt::ZERO ) return t1;
1130
1131 // Either input is BOTTOM ==> the result is BOTTOM
1132 if (t1 == Type::BOTTOM || t2 == Type::BOTTOM)
1133 return TypeLong::LONG;
1134
1135 if (t2 == TypeInt::INT)
1136 return TypeLong::LONG;
1137
1138 const TypeLong *r1 = t1->is_long(); // Handy access
1139 const TypeInt *r2 = t2->is_int (); // Handy access
1140
1141 // If the shift is a constant, just shift the bounds of the type.
1142 // For example, if the shift is 63, we just propagate sign bits.
1143 if (r2->is_con()) {
1144 uint shift = r2->get_con();
1145 shift &= (2*BitsPerJavaInteger)-1; // semantics of Java shifts
1146 // Shift by a multiple of 64 does nothing:
1147 if (shift == 0) return t1;
1148 // Calculate reasonably aggressive bounds for the result.
1149 // This is necessary if we are to correctly type things
1150 // like (x<<24>>24) == ((byte)x).
1151 jlong lo = (jlong)r1->_lo >> (jlong)shift;
1152 jlong hi = (jlong)r1->_hi >> (jlong)shift;
1153 assert(lo <= hi, "must have valid bounds");
1154 const TypeLong* tl = TypeLong::make(lo, hi, MAX2(r1->_widen,r2->_widen));
1155 #ifdef ASSERT
1156 // Make sure we get the sign-capture idiom correct.
1157 if (shift == (2*BitsPerJavaInteger)-1) {
1158 if (r1->_lo >= 0) assert(tl == TypeLong::ZERO, ">>63 of + is 0");
1159 if (r1->_hi < 0) assert(tl == TypeLong::MINUS_1, ">>63 of - is -1");
1160 }
1161 #endif
1162 return tl;
1163 }
1164
1165 return TypeLong::LONG; // Give up
1166 }
1167
1168 //=============================================================================
1169 //------------------------------Identity---------------------------------------
1170 Node* URShiftINode::Identity(PhaseGVN* phase) {
1171 int count = 0;
1172 if (const_shift_count(phase, this, &count) && (count & (BitsPerJavaInteger - 1)) == 0) {
1173 // Shift by a multiple of 32 does nothing
1174 return in(1);
1175 }
1176
1177 // Check for "((x << LogBytesPerWord) + (wordSize-1)) >> LogBytesPerWord" which is just "x".
1178 // Happens during new-array length computation.
1179 // Safe if 'x' is in the range [0..(max_int>>LogBytesPerWord)]
1180 Node *add = in(1);
1181 if (add->Opcode() == Op_AddI) {
1182 const TypeInt *t2 = phase->type(add->in(2))->isa_int();
1183 if (t2 && t2->is_con(wordSize - 1) &&
1184 add->in(1)->Opcode() == Op_LShiftI) {
1185 // Check that shift_counts are LogBytesPerWord.
1186 Node *lshift_count = add->in(1)->in(2);
1187 const TypeInt *t_lshift_count = phase->type(lshift_count)->isa_int();
1188 if (t_lshift_count && t_lshift_count->is_con(LogBytesPerWord) &&
1189 t_lshift_count == phase->type(in(2))) {
1190 Node *x = add->in(1)->in(1);
1191 const TypeInt *t_x = phase->type(x)->isa_int();
1192 if (t_x != NULL && 0 <= t_x->_lo && t_x->_hi <= (max_jint>>LogBytesPerWord)) {
1193 return x;
1194 }
1195 }
1196 }
1197 }
1198
1199 return (phase->type(in(2))->higher_equal(TypeInt::ZERO)) ? in(1) : this;
1200 }
1201
1202 //------------------------------Ideal------------------------------------------
1203 Node *URShiftINode::Ideal(PhaseGVN *phase, bool can_reshape) {
1204 int con = maskShiftAmount(phase, this, BitsPerJavaInteger);
1205 if (con == 0) {
1206 return NULL;
1207 }
1208
1209 // We'll be wanting the right-shift amount as a mask of that many bits
1210 const int mask = right_n_bits(BitsPerJavaInteger - con);
1211
1212 int in1_op = in(1)->Opcode();
1213
1214 // Check for ((x>>>a)>>>b) and replace with (x>>>(a+b)) when a+b < 32
1215 if( in1_op == Op_URShiftI ) {
1216 const TypeInt *t12 = phase->type( in(1)->in(2) )->isa_int();
1217 if( t12 && t12->is_con() ) { // Right input is a constant
1218 assert( in(1) != in(1)->in(1), "dead loop in URShiftINode::Ideal" );
1219 const int con2 = t12->get_con() & 31; // Shift count is always masked
1220 const int con3 = con+con2;
1221 if( con3 < 32 ) // Only merge shifts if total is < 32
1222 return new URShiftINode( in(1)->in(1), phase->intcon(con3) );
1223 }
1224 }
1225
1226 // Check for ((x << z) + Y) >>> z. Replace with x + con>>>z
1227 // The idiom for rounding to a power of 2 is "(Q+(2^z-1)) >>> z".
1228 // If Q is "X << z" the rounding is useless. Look for patterns like
1229 // ((X<<Z) + Y) >>> Z and replace with (X + Y>>>Z) & Z-mask.
1230 Node *add = in(1);
1231 const TypeInt *t2 = phase->type(in(2))->isa_int();
1232 if (in1_op == Op_AddI) {
1233 Node *lshl = add->in(1);
1234 if( lshl->Opcode() == Op_LShiftI &&
1235 phase->type(lshl->in(2)) == t2 ) {
1236 Node *y_z = phase->transform( new URShiftINode(add->in(2),in(2)) );
1237 Node *sum = phase->transform( new AddINode( lshl->in(1), y_z ) );
1238 return new AndINode( sum, phase->intcon(mask) );
1239 }
1240 }
1241
1242 // Check for (x & mask) >>> z. Replace with (x >>> z) & (mask >>> z)
1243 // This shortens the mask. Also, if we are extracting a high byte and
1244 // storing it to a buffer, the mask will be removed completely.
1245 Node *andi = in(1);
1246 if( in1_op == Op_AndI ) {
1247 const TypeInt *t3 = phase->type( andi->in(2) )->isa_int();
1248 if( t3 && t3->is_con() ) { // Right input is a constant
1249 jint mask2 = t3->get_con();
1250 mask2 >>= con; // *signed* shift downward (high-order zeroes do not help)
1251 Node *newshr = phase->transform( new URShiftINode(andi->in(1), in(2)) );
1252 return new AndINode(newshr, phase->intcon(mask2));
1253 // The negative values are easier to materialize than positive ones.
1254 // A typical case from address arithmetic is ((x & ~15) >> 4).
1255 // It's better to change that to ((x >> 4) & ~0) versus
1256 // ((x >> 4) & 0x0FFFFFFF). The difference is greatest in LP64.
1257 }
1258 }
1259
1260 // Check for "(X << z ) >>> z" which simply zero-extends
1261 Node *shl = in(1);
1262 if( in1_op == Op_LShiftI &&
1263 phase->type(shl->in(2)) == t2 )
1264 return new AndINode( shl->in(1), phase->intcon(mask) );
1265
1266 // Check for (x >> n) >>> 31. Replace with (x >>> 31)
1267 Node *shr = in(1);
1268 if ( in1_op == Op_RShiftI ) {
1269 Node *in11 = shr->in(1);
1270 Node *in12 = shr->in(2);
1271 const TypeInt *t11 = phase->type(in11)->isa_int();
1272 const TypeInt *t12 = phase->type(in12)->isa_int();
1273 if ( t11 && t2 && t2->is_con(31) && t12 && t12->is_con() ) {
1274 return new URShiftINode(in11, phase->intcon(31));
1275 }
1276 }
1277
1278 return NULL;
1279 }
1280
1281 //------------------------------Value------------------------------------------
1282 // A URShiftINode shifts its input2 right by input1 amount.
1283 const Type* URShiftINode::Value(PhaseGVN* phase) const {
1284 // (This is a near clone of RShiftINode::Value.)
1285 const Type *t1 = phase->type( in(1) );
1286 const Type *t2 = phase->type( in(2) );
1287 // Either input is TOP ==> the result is TOP
1288 if( t1 == Type::TOP ) return Type::TOP;
1289 if( t2 == Type::TOP ) return Type::TOP;
1290
1291 // Left input is ZERO ==> the result is ZERO.
1292 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
1293 // Shift by zero does nothing
1294 if( t2 == TypeInt::ZERO ) return t1;
1295
1296 // Either input is BOTTOM ==> the result is BOTTOM
1297 if (t1 == Type::BOTTOM || t2 == Type::BOTTOM)
1298 return TypeInt::INT;
1299
1300 if (t2 == TypeInt::INT)
1301 return TypeInt::INT;
1302
1303 const TypeInt *r1 = t1->is_int(); // Handy access
1304 const TypeInt *r2 = t2->is_int(); // Handy access
1305
1306 if (r2->is_con()) {
1307 uint shift = r2->get_con();
1308 shift &= BitsPerJavaInteger-1; // semantics of Java shifts
1309 // Shift by a multiple of 32 does nothing:
1310 if (shift == 0) return t1;
1311 // Calculate reasonably aggressive bounds for the result.
1312 jint lo = (juint)r1->_lo >> (juint)shift;
1313 jint hi = (juint)r1->_hi >> (juint)shift;
1314 if (r1->_hi >= 0 && r1->_lo < 0) {
1315 // If the type has both negative and positive values,
1316 // there are two separate sub-domains to worry about:
1317 // The positive half and the negative half.
1318 jint neg_lo = lo;
1319 jint neg_hi = (juint)-1 >> (juint)shift;
1320 jint pos_lo = (juint) 0 >> (juint)shift;
1321 jint pos_hi = hi;
1322 lo = MIN2(neg_lo, pos_lo); // == 0
1323 hi = MAX2(neg_hi, pos_hi); // == -1 >>> shift;
1324 }
1325 assert(lo <= hi, "must have valid bounds");
1326 const TypeInt* ti = TypeInt::make(lo, hi, MAX2(r1->_widen,r2->_widen));
1327 #ifdef ASSERT
1328 // Make sure we get the sign-capture idiom correct.
1329 if (shift == BitsPerJavaInteger-1) {
1330 if (r1->_lo >= 0) assert(ti == TypeInt::ZERO, ">>>31 of + is 0");
1331 if (r1->_hi < 0) assert(ti == TypeInt::ONE, ">>>31 of - is +1");
1332 }
1333 #endif
1334 return ti;
1335 }
1336
1337 //
1338 // Do not support shifted oops in info for GC
1339 //
1340 // else if( t1->base() == Type::InstPtr ) {
1341 //
1342 // const TypeInstPtr *o = t1->is_instptr();
1343 // if( t1->singleton() )
1344 // return TypeInt::make( ((uint32_t)o->const_oop() + o->_offset) >> shift );
1345 // }
1346 // else if( t1->base() == Type::KlassPtr ) {
1347 // const TypeKlassPtr *o = t1->is_klassptr();
1348 // if( t1->singleton() )
1349 // return TypeInt::make( ((uint32_t)o->const_oop() + o->_offset) >> shift );
1350 // }
1351
1352 return TypeInt::INT;
1353 }
1354
1355 //=============================================================================
1356 //------------------------------Identity---------------------------------------
1357 Node* URShiftLNode::Identity(PhaseGVN* phase) {
1358 int count = 0;
1359 if (const_shift_count(phase, this, &count) && (count & (BitsPerJavaLong - 1)) == 0) {
1360 // Shift by a multiple of 64 does nothing
1361 return in(1);
1362 }
1363 return this;
1364 }
1365
1366 //------------------------------Ideal------------------------------------------
1367 Node *URShiftLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1368 int con = maskShiftAmount(phase, this, BitsPerJavaLong);
1369 if (con == 0) {
1370 return NULL;
1371 }
1372
1373 // We'll be wanting the right-shift amount as a mask of that many bits
1374 const jlong mask = jlong(max_julong >> con);
1375
1376 // Check for ((x << z) + Y) >>> z. Replace with x + con>>>z
1377 // The idiom for rounding to a power of 2 is "(Q+(2^z-1)) >>> z".
1378 // If Q is "X << z" the rounding is useless. Look for patterns like
1379 // ((X<<Z) + Y) >>> Z and replace with (X + Y>>>Z) & Z-mask.
1380 Node *add = in(1);
1381 const TypeInt *t2 = phase->type(in(2))->isa_int();
1382 if (add->Opcode() == Op_AddL) {
1383 Node *lshl = add->in(1);
1384 if( lshl->Opcode() == Op_LShiftL &&
1385 phase->type(lshl->in(2)) == t2 ) {
1386 Node *y_z = phase->transform( new URShiftLNode(add->in(2),in(2)) );
1387 Node *sum = phase->transform( new AddLNode( lshl->in(1), y_z ) );
1388 return new AndLNode( sum, phase->longcon(mask) );
1389 }
1390 }
1391
1392 // Check for (x & mask) >>> z. Replace with (x >>> z) & (mask >>> z)
1393 // This shortens the mask. Also, if we are extracting a high byte and
1394 // storing it to a buffer, the mask will be removed completely.
1395 Node *andi = in(1);
1396 if( andi->Opcode() == Op_AndL ) {
1397 const TypeLong *t3 = phase->type( andi->in(2) )->isa_long();
1398 if( t3 && t3->is_con() ) { // Right input is a constant
1399 jlong mask2 = t3->get_con();
1400 mask2 >>= con; // *signed* shift downward (high-order zeroes do not help)
1401 Node *newshr = phase->transform( new URShiftLNode(andi->in(1), in(2)) );
1402 return new AndLNode(newshr, phase->longcon(mask2));
1403 }
1404 }
1405
1406 // Check for "(X << z ) >>> z" which simply zero-extends
1407 Node *shl = in(1);
1408 if( shl->Opcode() == Op_LShiftL &&
1409 phase->type(shl->in(2)) == t2 )
1410 return new AndLNode( shl->in(1), phase->longcon(mask) );
1411
1412 // Check for (x >> n) >>> 63. Replace with (x >>> 63)
1413 Node *shr = in(1);
1414 if ( shr->Opcode() == Op_RShiftL ) {
1415 Node *in11 = shr->in(1);
1416 Node *in12 = shr->in(2);
1417 const TypeLong *t11 = phase->type(in11)->isa_long();
1418 const TypeInt *t12 = phase->type(in12)->isa_int();
1419 if ( t11 && t2 && t2->is_con(63) && t12 && t12->is_con() ) {
1420 return new URShiftLNode(in11, phase->intcon(63));
1421 }
1422 }
1423 return NULL;
1424 }
1425
1426 //------------------------------Value------------------------------------------
1427 // A URShiftINode shifts its input2 right by input1 amount.
1428 const Type* URShiftLNode::Value(PhaseGVN* phase) const {
1429 // (This is a near clone of RShiftLNode::Value.)
1430 const Type *t1 = phase->type( in(1) );
1431 const Type *t2 = phase->type( in(2) );
1432 // Either input is TOP ==> the result is TOP
1433 if( t1 == Type::TOP ) return Type::TOP;
1434 if( t2 == Type::TOP ) return Type::TOP;
1435
1436 // Left input is ZERO ==> the result is ZERO.
1437 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
1438 // Shift by zero does nothing
1439 if( t2 == TypeInt::ZERO ) return t1;
1440
1441 // Either input is BOTTOM ==> the result is BOTTOM
1442 if (t1 == Type::BOTTOM || t2 == Type::BOTTOM)
1443 return TypeLong::LONG;
1444
1445 if (t2 == TypeInt::INT)
1446 return TypeLong::LONG;
1447
1448 const TypeLong *r1 = t1->is_long(); // Handy access
1449 const TypeInt *r2 = t2->is_int (); // Handy access
1450
1451 if (r2->is_con()) {
1452 uint shift = r2->get_con();
1453 shift &= BitsPerJavaLong - 1; // semantics of Java shifts
1454 // Shift by a multiple of 64 does nothing:
1455 if (shift == 0) return t1;
1456 // Calculate reasonably aggressive bounds for the result.
1457 jlong lo = (julong)r1->_lo >> (juint)shift;
1458 jlong hi = (julong)r1->_hi >> (juint)shift;
1459 if (r1->_hi >= 0 && r1->_lo < 0) {
1460 // If the type has both negative and positive values,
1461 // there are two separate sub-domains to worry about:
1462 // The positive half and the negative half.
1463 jlong neg_lo = lo;
1464 jlong neg_hi = (julong)-1 >> (juint)shift;
1465 jlong pos_lo = (julong) 0 >> (juint)shift;
1466 jlong pos_hi = hi;
1467 //lo = MIN2(neg_lo, pos_lo); // == 0
1468 lo = neg_lo < pos_lo ? neg_lo : pos_lo;
1469 //hi = MAX2(neg_hi, pos_hi); // == -1 >>> shift;
1470 hi = neg_hi > pos_hi ? neg_hi : pos_hi;
1471 }
1472 assert(lo <= hi, "must have valid bounds");
1473 const TypeLong* tl = TypeLong::make(lo, hi, MAX2(r1->_widen,r2->_widen));
1474 #ifdef ASSERT
1475 // Make sure we get the sign-capture idiom correct.
1476 if (shift == BitsPerJavaLong - 1) {
1477 if (r1->_lo >= 0) assert(tl == TypeLong::ZERO, ">>>63 of + is 0");
1478 if (r1->_hi < 0) assert(tl == TypeLong::ONE, ">>>63 of - is +1");
1479 }
1480 #endif
1481 return tl;
1482 }
1483
1484 return TypeLong::LONG; // Give up
1485 }
1486
1487 //=============================================================================
1488 //------------------------------Value------------------------------------------
1489 const Type* FmaDNode::Value(PhaseGVN* phase) const {
1490 const Type *t1 = phase->type(in(1));
1491 if (t1 == Type::TOP) return Type::TOP;
1492 if (t1->base() != Type::DoubleCon) return Type::DOUBLE;
1493 const Type *t2 = phase->type(in(2));
1494 if (t2 == Type::TOP) return Type::TOP;
1495 if (t2->base() != Type::DoubleCon) return Type::DOUBLE;
1496 const Type *t3 = phase->type(in(3));
1497 if (t3 == Type::TOP) return Type::TOP;
1498 if (t3->base() != Type::DoubleCon) return Type::DOUBLE;
1499 #ifndef __STDC_IEC_559__
1500 return Type::DOUBLE;
1501 #else
1502 double d1 = t1->getd();
1503 double d2 = t2->getd();
1504 double d3 = t3->getd();
1505 return TypeD::make(fma(d1, d2, d3));
1506 #endif
1507 }
1508
1509 //=============================================================================
1510 //------------------------------Value------------------------------------------
1511 const Type* FmaFNode::Value(PhaseGVN* phase) const {
1512 const Type *t1 = phase->type(in(1));
1513 if (t1 == Type::TOP) return Type::TOP;
1514 if (t1->base() != Type::FloatCon) return Type::FLOAT;
1515 const Type *t2 = phase->type(in(2));
1516 if (t2 == Type::TOP) return Type::TOP;
1517 if (t2->base() != Type::FloatCon) return Type::FLOAT;
1518 const Type *t3 = phase->type(in(3));
1519 if (t3 == Type::TOP) return Type::TOP;
1520 if (t3->base() != Type::FloatCon) return Type::FLOAT;
1521 #ifndef __STDC_IEC_559__
1522 return Type::FLOAT;
1523 #else
1524 float f1 = t1->getf();
1525 float f2 = t2->getf();
1526 float f3 = t3->getf();
1527 return TypeF::make(fma(f1, f2, f3));
1528 #endif
1529 }
1530
1531 //=============================================================================
1532 //------------------------------hash-------------------------------------------
1533 // Hash function for MulAddS2INode. Operation is commutative with commutative pairs.
1534 // The hash function must return the same value when edge swapping is performed.
1535 uint MulAddS2INode::hash() const {
1536 return (uintptr_t)in(1) + (uintptr_t)in(2) + (uintptr_t)in(3) + (uintptr_t)in(4) + Opcode();
1537 }
1538
1539 //------------------------------Rotate Operations ------------------------------
1540
1541 Node* RotateLeftNode::Identity(PhaseGVN* phase) {
1542 const Type* t1 = phase->type(in(1));
1543 if (t1 == Type::TOP) {
1544 return this;
1545 }
1546 int count = 0;
1547 assert(t1->isa_int() || t1->isa_long(), "Unexpected type");
1548 int mask = (t1->isa_int() ? BitsPerJavaInteger : BitsPerJavaLong) - 1;
1549 if (const_shift_count(phase, this, &count) && (count & mask) == 0) {
1550 // Rotate by a multiple of 32/64 does nothing
1551 return in(1);
1552 }
1553 return this;
1554 }
1555
1556 const Type* RotateLeftNode::Value(PhaseGVN* phase) const {
1557 const Type* t1 = phase->type(in(1));
1558 const Type* t2 = phase->type(in(2));
1559 // Either input is TOP ==> the result is TOP
1560 if (t1 == Type::TOP || t2 == Type::TOP) {
1561 return Type::TOP;
1562 }
1563
1564 if (t1->isa_int()) {
1565 const TypeInt* r1 = t1->is_int();
1566 const TypeInt* r2 = t2->is_int();
1567
1568 // Left input is ZERO ==> the result is ZERO.
1569 if (r1 == TypeInt::ZERO) {
1570 return TypeInt::ZERO;
1571 }
1572 // Rotate by zero does nothing
1573 if (r2 == TypeInt::ZERO) {
1574 return r1;
1575 }
1576 if (r1->is_con() && r2->is_con()) {
1577 juint r1_con = (juint)r1->get_con();
1578 juint shift = (juint)(r2->get_con()) & (juint)(BitsPerJavaInteger - 1); // semantics of Java shifts
1579 return TypeInt::make((r1_con << shift) | (r1_con >> (32 - shift)));
1580 }
1581 return TypeInt::INT;
1582 } else {
1583 assert(t1->isa_long(), "Type must be a long");
1584 const TypeLong* r1 = t1->is_long();
1585 const TypeInt* r2 = t2->is_int();
1586
1587 // Left input is ZERO ==> the result is ZERO.
1588 if (r1 == TypeLong::ZERO) {
1589 return TypeLong::ZERO;
1590 }
1591 // Rotate by zero does nothing
1592 if (r2 == TypeInt::ZERO) {
1593 return r1;
1594 }
1595 if (r1->is_con() && r2->is_con()) {
1596 julong r1_con = (julong)r1->get_con();
1597 julong shift = (julong)(r2->get_con()) & (julong)(BitsPerJavaLong - 1); // semantics of Java shifts
1598 return TypeLong::make((r1_con << shift) | (r1_con >> (64 - shift)));
1599 }
1600 return TypeLong::LONG;
1601 }
1602 }
1603
1604 Node* RotateLeftNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1605 const Type* t1 = phase->type(in(1));
1606 const Type* t2 = phase->type(in(2));
1607 if (t2->isa_int() && t2->is_int()->is_con()) {
1608 if (t1->isa_int()) {
1609 int lshift = t2->is_int()->get_con() & 31;
1610 return new RotateRightNode(in(1), phase->intcon(32 - (lshift & 31)), TypeInt::INT);
1611 } else if (t1 != Type::TOP) {
1612 assert(t1->isa_long(), "Type must be a long");
1613 int lshift = t2->is_int()->get_con() & 63;
1614 return new RotateRightNode(in(1), phase->intcon(64 - (lshift & 63)), TypeLong::LONG);
1615 }
1616 }
1617 return NULL;
1618 }
1619
1620 Node* RotateRightNode::Identity(PhaseGVN* phase) {
1621 const Type* t1 = phase->type(in(1));
1622 if (t1 == Type::TOP) {
1623 return this;
1624 }
1625 int count = 0;
1626 assert(t1->isa_int() || t1->isa_long(), "Unexpected type");
1627 int mask = (t1->isa_int() ? BitsPerJavaInteger : BitsPerJavaLong) - 1;
1628 if (const_shift_count(phase, this, &count) && (count & mask) == 0) {
1629 // Rotate by a multiple of 32/64 does nothing
1630 return in(1);
1631 }
1632 return this;
1633 }
1634
1635 const Type* RotateRightNode::Value(PhaseGVN* phase) const {
1636 const Type* t1 = phase->type(in(1));
1637 const Type* t2 = phase->type(in(2));
1638 // Either input is TOP ==> the result is TOP
1639 if (t1 == Type::TOP || t2 == Type::TOP) {
1640 return Type::TOP;
1641 }
1642
1643 if (t1->isa_int()) {
1644 const TypeInt* r1 = t1->is_int();
1645 const TypeInt* r2 = t2->is_int();
1646
1647 // Left input is ZERO ==> the result is ZERO.
1648 if (r1 == TypeInt::ZERO) {
1649 return TypeInt::ZERO;
1650 }
1651 // Rotate by zero does nothing
1652 if (r2 == TypeInt::ZERO) {
1653 return r1;
1654 }
1655 if (r1->is_con() && r2->is_con()) {
1656 juint r1_con = (juint)r1->get_con();
1657 juint shift = (juint)(r2->get_con()) & (juint)(BitsPerJavaInteger - 1); // semantics of Java shifts
1658 return TypeInt::make((r1_con >> shift) | (r1_con << (32 - shift)));
1659 }
1660 return TypeInt::INT;
1661 } else {
1662 assert(t1->isa_long(), "Type must be a long");
1663 const TypeLong* r1 = t1->is_long();
1664 const TypeInt* r2 = t2->is_int();
1665 // Left input is ZERO ==> the result is ZERO.
1666 if (r1 == TypeLong::ZERO) {
1667 return TypeLong::ZERO;
1668 }
1669 // Rotate by zero does nothing
1670 if (r2 == TypeInt::ZERO) {
1671 return r1;
1672 }
1673 if (r1->is_con() && r2->is_con()) {
1674 julong r1_con = (julong)r1->get_con();
1675 julong shift = (julong)(r2->get_con()) & (julong)(BitsPerJavaLong - 1); // semantics of Java shifts
1676 return TypeLong::make((r1_con >> shift) | (r1_con << (64 - shift)));
1677 }
1678 return TypeLong::LONG;
1679 }
1680 }