1 /*
2 * Copyright (c) 2014, 2019, 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 "opto/addnode.hpp"
27 #include "opto/castnode.hpp"
28 #include "opto/convertnode.hpp"
29 #include "opto/matcher.hpp"
30 #include "opto/phaseX.hpp"
31 #include "opto/subnode.hpp"
32 #include "runtime/sharedRuntime.hpp"
33
34 //=============================================================================
35 //------------------------------Identity---------------------------------------
36 Node* Conv2BNode::Identity(PhaseGVN* phase) {
37 const Type *t = phase->type( in(1) );
38 if( t == Type::TOP ) return in(1);
39 if( t == TypeInt::ZERO ) return in(1);
40 if( t == TypeInt::ONE ) return in(1);
41 if( t == TypeInt::BOOL ) return in(1);
42 return this;
43 }
44
45 //------------------------------Value------------------------------------------
46 const Type* Conv2BNode::Value(PhaseGVN* phase) const {
47 const Type *t = phase->type( in(1) );
48 if( t == Type::TOP ) return Type::TOP;
49 if( t == TypeInt::ZERO ) return TypeInt::ZERO;
50 if( t == TypePtr::NULL_PTR ) return TypeInt::ZERO;
51 const TypePtr *tp = t->isa_ptr();
52 if( tp != NULL ) {
53 if( tp->ptr() == TypePtr::AnyNull ) return Type::TOP;
54 if( tp->ptr() == TypePtr::Constant) return TypeInt::ONE;
55 if (tp->ptr() == TypePtr::NotNull) return TypeInt::ONE;
56 return TypeInt::BOOL;
57 }
58 if (t->base() != Type::Int) return TypeInt::BOOL;
59 const TypeInt *ti = t->is_int();
60 if( ti->_hi < 0 || ti->_lo > 0 ) return TypeInt::ONE;
61 return TypeInt::BOOL;
62 }
63
64
65 // The conversions operations are all Alpha sorted. Please keep it that way!
66 //=============================================================================
67 //------------------------------Value------------------------------------------
68 const Type* ConvD2FNode::Value(PhaseGVN* phase) const {
69 const Type *t = phase->type( in(1) );
70 if( t == Type::TOP ) return Type::TOP;
71 if( t == Type::DOUBLE ) return Type::FLOAT;
72 const TypeD *td = t->is_double_constant();
73 return TypeF::make( (float)td->getd() );
74 }
75
76 //------------------------------Ideal------------------------------------------
77 // If we see pattern ConvF2D SomeDoubleOp ConvD2F, do operation as float.
78 Node *ConvD2FNode::Ideal(PhaseGVN *phase, bool can_reshape) {
79 if ( in(1)->Opcode() == Op_SqrtD ) {
80 Node* sqrtd = in(1);
81 if ( sqrtd->in(1)->Opcode() == Op_ConvF2D ) {
82 if ( Matcher::match_rule_supported(Op_SqrtF) ) {
83 Node* convf2d = sqrtd->in(1);
84 return new SqrtFNode(phase->C, sqrtd->in(0), convf2d->in(1));
85 }
86 }
87 }
88 return NULL;
89 }
90
91 //------------------------------Identity---------------------------------------
92 // Float's can be converted to doubles with no loss of bits. Hence
93 // converting a float to a double and back to a float is a NOP.
94 Node* ConvD2FNode::Identity(PhaseGVN* phase) {
95 return (in(1)->Opcode() == Op_ConvF2D) ? in(1)->in(1) : this;
96 }
97
98 //=============================================================================
99 //------------------------------Value------------------------------------------
100 const Type* ConvD2INode::Value(PhaseGVN* phase) const {
101 const Type *t = phase->type( in(1) );
102 if( t == Type::TOP ) return Type::TOP;
103 if( t == Type::DOUBLE ) return TypeInt::INT;
104 const TypeD *td = t->is_double_constant();
105 return TypeInt::make( SharedRuntime::d2i( td->getd() ) );
106 }
107
108 //------------------------------Ideal------------------------------------------
109 // If converting to an int type, skip any rounding nodes
110 Node *ConvD2INode::Ideal(PhaseGVN *phase, bool can_reshape) {
111 if( in(1)->Opcode() == Op_RoundDouble )
112 set_req(1,in(1)->in(1));
113 return NULL;
114 }
115
116 //------------------------------Identity---------------------------------------
117 // Int's can be converted to doubles with no loss of bits. Hence
118 // converting an integer to a double and back to an integer is a NOP.
119 Node* ConvD2INode::Identity(PhaseGVN* phase) {
120 return (in(1)->Opcode() == Op_ConvI2D) ? in(1)->in(1) : this;
121 }
122
123 //=============================================================================
124 //------------------------------Value------------------------------------------
125 const Type* ConvD2LNode::Value(PhaseGVN* phase) const {
126 const Type *t = phase->type( in(1) );
127 if( t == Type::TOP ) return Type::TOP;
128 if( t == Type::DOUBLE ) return TypeLong::LONG;
129 const TypeD *td = t->is_double_constant();
130 return TypeLong::make( SharedRuntime::d2l( td->getd() ) );
131 }
132
133 //------------------------------Identity---------------------------------------
134 Node* ConvD2LNode::Identity(PhaseGVN* phase) {
135 // Remove ConvD2L->ConvL2D->ConvD2L sequences.
136 if( in(1) ->Opcode() == Op_ConvL2D &&
137 in(1)->in(1)->Opcode() == Op_ConvD2L )
138 return in(1)->in(1);
139 return this;
140 }
141
142 //------------------------------Ideal------------------------------------------
143 // If converting to an int type, skip any rounding nodes
144 Node *ConvD2LNode::Ideal(PhaseGVN *phase, bool can_reshape) {
145 if( in(1)->Opcode() == Op_RoundDouble )
146 set_req(1,in(1)->in(1));
147 return NULL;
148 }
149
150 //=============================================================================
151 //------------------------------Value------------------------------------------
152 const Type* ConvF2DNode::Value(PhaseGVN* phase) const {
153 const Type *t = phase->type( in(1) );
154 if( t == Type::TOP ) return Type::TOP;
155 if( t == Type::FLOAT ) return Type::DOUBLE;
156 const TypeF *tf = t->is_float_constant();
157 return TypeD::make( (double)tf->getf() );
158 }
159
160 //=============================================================================
161 //------------------------------Value------------------------------------------
162 const Type* ConvF2INode::Value(PhaseGVN* phase) const {
163 const Type *t = phase->type( in(1) );
164 if( t == Type::TOP ) return Type::TOP;
165 if( t == Type::FLOAT ) return TypeInt::INT;
166 const TypeF *tf = t->is_float_constant();
167 return TypeInt::make( SharedRuntime::f2i( tf->getf() ) );
168 }
169
170 //------------------------------Identity---------------------------------------
171 Node* ConvF2INode::Identity(PhaseGVN* phase) {
172 // Remove ConvF2I->ConvI2F->ConvF2I sequences.
173 if( in(1) ->Opcode() == Op_ConvI2F &&
174 in(1)->in(1)->Opcode() == Op_ConvF2I )
175 return in(1)->in(1);
176 return this;
177 }
178
179 //------------------------------Ideal------------------------------------------
180 // If converting to an int type, skip any rounding nodes
181 Node *ConvF2INode::Ideal(PhaseGVN *phase, bool can_reshape) {
182 if( in(1)->Opcode() == Op_RoundFloat )
183 set_req(1,in(1)->in(1));
184 return NULL;
185 }
186
187 //=============================================================================
188 //------------------------------Value------------------------------------------
189 const Type* ConvF2LNode::Value(PhaseGVN* phase) const {
190 const Type *t = phase->type( in(1) );
191 if( t == Type::TOP ) return Type::TOP;
192 if( t == Type::FLOAT ) return TypeLong::LONG;
193 const TypeF *tf = t->is_float_constant();
194 return TypeLong::make( SharedRuntime::f2l( tf->getf() ) );
195 }
196
197 //------------------------------Identity---------------------------------------
198 Node* ConvF2LNode::Identity(PhaseGVN* phase) {
199 // Remove ConvF2L->ConvL2F->ConvF2L sequences.
200 if( in(1) ->Opcode() == Op_ConvL2F &&
201 in(1)->in(1)->Opcode() == Op_ConvF2L )
202 return in(1)->in(1);
203 return this;
204 }
205
206 //------------------------------Ideal------------------------------------------
207 // If converting to an int type, skip any rounding nodes
208 Node *ConvF2LNode::Ideal(PhaseGVN *phase, bool can_reshape) {
209 if( in(1)->Opcode() == Op_RoundFloat )
210 set_req(1,in(1)->in(1));
211 return NULL;
212 }
213
214 //=============================================================================
215 //------------------------------Value------------------------------------------
216 const Type* ConvI2DNode::Value(PhaseGVN* phase) const {
217 const Type *t = phase->type( in(1) );
218 if( t == Type::TOP ) return Type::TOP;
219 const TypeInt *ti = t->is_int();
220 if( ti->is_con() ) return TypeD::make( (double)ti->get_con() );
221 return bottom_type();
222 }
223
224 //=============================================================================
225 //------------------------------Value------------------------------------------
226 const Type* ConvI2FNode::Value(PhaseGVN* phase) const {
227 const Type *t = phase->type( in(1) );
228 if( t == Type::TOP ) return Type::TOP;
229 const TypeInt *ti = t->is_int();
230 if( ti->is_con() ) return TypeF::make( (float)ti->get_con() );
231 return bottom_type();
232 }
233
234 //------------------------------Identity---------------------------------------
235 Node* ConvI2FNode::Identity(PhaseGVN* phase) {
236 // Remove ConvI2F->ConvF2I->ConvI2F sequences.
237 if( in(1) ->Opcode() == Op_ConvF2I &&
238 in(1)->in(1)->Opcode() == Op_ConvI2F )
239 return in(1)->in(1);
240 return this;
241 }
242
243 //=============================================================================
244 //------------------------------Value------------------------------------------
245 const Type* ConvI2LNode::Value(PhaseGVN* phase) const {
246 const Type *t = phase->type( in(1) );
247 if( t == Type::TOP ) return Type::TOP;
248 const TypeInt *ti = t->is_int();
249 const Type* tl = TypeLong::make(ti->_lo, ti->_hi, ti->_widen);
250 // Join my declared type against my incoming type.
251 tl = tl->filter(_type);
252 return tl;
253 }
254
255 static inline bool long_ranges_overlap(jlong lo1, jlong hi1,
256 jlong lo2, jlong hi2) {
257 // Two ranges overlap iff one range's low point falls in the other range.
258 return (lo2 <= lo1 && lo1 <= hi2) || (lo1 <= lo2 && lo2 <= hi1);
259 }
260
261 #ifdef _LP64
262 // If there is an existing ConvI2L node with the given parent and type, return
263 // it. Otherwise, create and return a new one. Both reusing existing ConvI2L
264 // nodes and postponing the idealization of new ones are needed to avoid an
265 // explosion of recursive Ideal() calls when compiling long AddI chains.
266 static Node* find_or_make_convI2L(PhaseIterGVN* igvn, Node* parent,
267 const TypeLong* type) {
268 Node* n = new ConvI2LNode(parent, type);
269 Node* existing = igvn->hash_find_insert(n);
270 if (existing != NULL) {
271 n->destruct(igvn);
272 return existing;
273 }
274 return igvn->register_new_node_with_optimizer(n);
275 }
276 #endif
277
278 bool Compile::push_thru_add(PhaseGVN* phase, Node* z, const TypeInteger* tz, const TypeInteger*& rx, const TypeInteger*& ry,
279 BasicType bt) {
280 int op = z->Opcode();
281 if (op == Op_AddI || op == Op_SubI) {
282 Node* x = z->in(1);
283 Node* y = z->in(2);
284 assert (x != z && y != z, "dead loop in ConvI2LNode::Ideal");
285 if (phase->type(x) == Type::TOP) {
286 return false;
287 }
288 if (phase->type(y) == Type::TOP) {
289 return false;
290 }
291 const TypeInt* tx = phase->type(x)->is_int();
292 const TypeInt* ty = phase->type(y)->is_int();
293
294 jlong xlo = tx->is_int()->_lo;
295 jlong xhi = tx->is_int()->_hi;
296 jlong ylo = ty->is_int()->_lo;
297 jlong yhi = ty->is_int()->_hi;
298 jlong zlo = tz->lo_as_long();
299 jlong zhi = tz->hi_as_long();
300 jlong vbit = CONST64(1) << BitsPerInt;
301 int widen = MAX2(tx->_widen, ty->_widen);
302 if (op == Op_SubI) {
303 jlong ylo0 = ylo;
304 ylo = -yhi;
305 yhi = -ylo0;
306 }
307 // See if x+y can cause positive overflow into z+2**32
308 if (long_ranges_overlap(xlo+ylo, xhi+yhi, zlo+vbit, zhi+vbit)) {
309 return false;
310 }
311 // See if x+y can cause negative overflow into z-2**32
312 if (long_ranges_overlap(xlo+ylo, xhi+yhi, zlo-vbit, zhi-vbit)) {
313 return false;
314 }
315 // Now it's always safe to assume x+y does not overflow.
316 // This is true even if some pairs x,y might cause overflow, as long
317 // as that overflow value cannot fall into [zlo,zhi].
318
319 // Confident that the arithmetic is "as if infinite precision",
320 // we can now use z's range to put constraints on those of x and y.
321 // The "natural" range of x [xlo,xhi] can perhaps be narrowed to a
322 // more "restricted" range by intersecting [xlo,xhi] with the
323 // range obtained by subtracting y's range from the asserted range
324 // of the I2L conversion. Here's the interval arithmetic algebra:
325 // x == z-y == [zlo,zhi]-[ylo,yhi] == [zlo,zhi]+[-yhi,-ylo]
326 // => x in [zlo-yhi, zhi-ylo]
327 // => x in [zlo-yhi, zhi-ylo] INTERSECT [xlo,xhi]
328 // => x in [xlo MAX zlo-yhi, xhi MIN zhi-ylo]
329 jlong rxlo = MAX2(xlo, zlo - yhi);
330 jlong rxhi = MIN2(xhi, zhi - ylo);
331 // And similarly, x changing place with y:
332 jlong rylo = MAX2(ylo, zlo - xhi);
333 jlong ryhi = MIN2(yhi, zhi - xlo);
334 if (rxlo > rxhi || rylo > ryhi) {
335 return false; // x or y is dying; don't mess w/ it
336 }
337 if (op == Op_SubI) {
338 jlong rylo0 = rylo;
339 rylo = -ryhi;
340 ryhi = -rylo0;
341 }
342 assert(rxlo == (int)rxlo && rxhi == (int)rxhi, "x should not overflow");
343 assert(rylo == (int)rylo && ryhi == (int)ryhi, "y should not overflow");
344 rx = TypeInteger::make(rxlo, rxhi, widen, bt);
345 ry = TypeInteger::make(rylo, ryhi, widen, bt);
346 return true;
347 }
348 return false;
349 }
350
351
352 //------------------------------Ideal------------------------------------------
353 Node *ConvI2LNode::Ideal(PhaseGVN *phase, bool can_reshape) {
354 PhaseIterGVN *igvn = phase->is_IterGVN();
355 const TypeLong* this_type = this->type()->is_long();
356 Node* this_changed = NULL;
357
358 if (igvn != NULL) {
359 // Do NOT remove this node's type assertion until no more loop ops can happen.
360 if (phase->C->post_loop_opts_phase()) {
361 const TypeInt* in_type = phase->type(in(1))->isa_int();
362 if (in_type != NULL && this_type != NULL &&
363 (in_type->_lo != this_type->_lo ||
364 in_type->_hi != this_type->_hi)) {
365 // Although this WORSENS the type, it increases GVN opportunities,
366 // because I2L nodes with the same input will common up, regardless
367 // of slightly differing type assertions. Such slight differences
368 // arise routinely as a result of loop unrolling, so this is a
369 // post-unrolling graph cleanup. Choose a type which depends only
370 // on my input. (Exception: Keep a range assertion of >=0 or <0.)
371 jlong lo1 = this_type->_lo;
372 jlong hi1 = this_type->_hi;
373 int w1 = this_type->_widen;
374 if (lo1 != (jint)lo1 ||
375 hi1 != (jint)hi1 ||
376 lo1 > hi1) {
377 // Overflow leads to wraparound, wraparound leads to range saturation.
378 lo1 = min_jint; hi1 = max_jint;
379 } else if (lo1 >= 0) {
380 // Keep a range assertion of >=0.
381 lo1 = 0; hi1 = max_jint;
382 } else if (hi1 < 0) {
383 // Keep a range assertion of <0.
384 lo1 = min_jint; hi1 = -1;
385 } else {
386 lo1 = min_jint; hi1 = max_jint;
387 }
388 const TypeLong* wtype = TypeLong::make(MAX2((jlong)in_type->_lo, lo1),
389 MIN2((jlong)in_type->_hi, hi1),
390 MAX2((int)in_type->_widen, w1));
391 if (wtype != type()) {
392 set_type(wtype);
393 // Note: this_type still has old type value, for the logic below.
394 this_changed = this;
395 }
396 }
397 } else {
398 phase->C->record_for_post_loop_opts_igvn(this);
399 }
400 }
401 #ifdef _LP64
402 // Convert ConvI2L(AddI(x, y)) to AddL(ConvI2L(x), ConvI2L(y))
403 // but only if x and y have subranges that cannot cause 32-bit overflow,
404 // under the assumption that x+y is in my own subrange this->type().
405
406 // This assumption is based on a constraint (i.e., type assertion)
407 // established in Parse::array_addressing or perhaps elsewhere.
408 // This constraint has been adjoined to the "natural" type of
409 // the incoming argument in(0). We know (because of runtime
410 // checks) - that the result value I2L(x+y) is in the joined range.
411 // Hence we can restrict the incoming terms (x, y) to values such
412 // that their sum also lands in that range.
413
414 // This optimization is useful only on 64-bit systems, where we hope
415 // the addition will end up subsumed in an addressing mode.
416 // It is necessary to do this when optimizing an unrolled array
417 // copy loop such as x[i++] = y[i++].
418
419 // On 32-bit systems, it's better to perform as much 32-bit math as
420 // possible before the I2L conversion, because 32-bit math is cheaper.
421 // There's no common reason to "leak" a constant offset through the I2L.
422 // Addressing arithmetic will not absorb it as part of a 64-bit AddL.
423
424 Node* z = in(1);
425 const TypeInteger* rx = NULL;
426 const TypeInteger* ry = NULL;
427 if (Compile::push_thru_add(phase, z, this_type, rx, ry, T_LONG)) {
428 if (igvn == NULL) {
429 // Postpone this optimization to iterative GVN, where we can handle deep
430 // AddI chains without an exponential number of recursive Ideal() calls.
431 phase->record_for_igvn(this);
432 return this_changed;
433 }
434 int op = z->Opcode();
435 Node* x = z->in(1);
436 Node* y = z->in(2);
437
438 Node* cx = find_or_make_convI2L(igvn, x, rx->is_long());
439 Node* cy = find_or_make_convI2L(igvn, y, ry->is_long());
440 switch (op) {
441 case Op_AddI: return new AddLNode(cx, cy);
442 case Op_SubI: return new SubLNode(cx, cy);
443 default: ShouldNotReachHere();
444 }
445 }
446 #endif //_LP64
447
448 return this_changed;
449 }
450
451 //=============================================================================
452 //------------------------------Value------------------------------------------
453 const Type* ConvL2DNode::Value(PhaseGVN* phase) const {
454 const Type *t = phase->type( in(1) );
455 if( t == Type::TOP ) return Type::TOP;
456 const TypeLong *tl = t->is_long();
457 if( tl->is_con() ) return TypeD::make( (double)tl->get_con() );
458 return bottom_type();
459 }
460
461 //=============================================================================
462 //------------------------------Value------------------------------------------
463 const Type* ConvL2FNode::Value(PhaseGVN* phase) const {
464 const Type *t = phase->type( in(1) );
465 if( t == Type::TOP ) return Type::TOP;
466 const TypeLong *tl = t->is_long();
467 if( tl->is_con() ) return TypeF::make( (float)tl->get_con() );
468 return bottom_type();
469 }
470
471 //=============================================================================
472 //----------------------------Identity-----------------------------------------
473 Node* ConvL2INode::Identity(PhaseGVN* phase) {
474 // Convert L2I(I2L(x)) => x
475 if (in(1)->Opcode() == Op_ConvI2L) return in(1)->in(1);
476 return this;
477 }
478
479 //------------------------------Value------------------------------------------
480 const Type* ConvL2INode::Value(PhaseGVN* phase) const {
481 const Type *t = phase->type( in(1) );
482 if( t == Type::TOP ) return Type::TOP;
483 const TypeLong *tl = t->is_long();
484 const TypeInt* ti = TypeInt::INT;
485 if (tl->is_con()) {
486 // Easy case.
487 ti = TypeInt::make((jint)tl->get_con());
488 } else if (tl->_lo >= min_jint && tl->_hi <= max_jint) {
489 ti = TypeInt::make((jint)tl->_lo, (jint)tl->_hi, tl->_widen);
490 }
491 return ti->filter(_type);
492 }
493
494 //------------------------------Ideal------------------------------------------
495 // Return a node which is more "ideal" than the current node.
496 // Blow off prior masking to int
497 Node *ConvL2INode::Ideal(PhaseGVN *phase, bool can_reshape) {
498 Node *andl = in(1);
499 uint andl_op = andl->Opcode();
500 if( andl_op == Op_AndL ) {
501 // Blow off prior masking to int
502 if( phase->type(andl->in(2)) == TypeLong::make( 0xFFFFFFFF ) ) {
503 set_req_X(1,andl->in(1), phase);
504 return this;
505 }
506 }
507
508 // Swap with a prior add: convL2I(addL(x,y)) ==> addI(convL2I(x),convL2I(y))
509 // This replaces an 'AddL' with an 'AddI'.
510 if( andl_op == Op_AddL ) {
511 // Don't do this for nodes which have more than one user since
512 // we'll end up computing the long add anyway.
513 if (andl->outcnt() > 1) return NULL;
514
515 Node* x = andl->in(1);
516 Node* y = andl->in(2);
517 assert( x != andl && y != andl, "dead loop in ConvL2INode::Ideal" );
518 if (phase->type(x) == Type::TOP) return NULL;
519 if (phase->type(y) == Type::TOP) return NULL;
520 Node *add1 = phase->transform(new ConvL2INode(x));
521 Node *add2 = phase->transform(new ConvL2INode(y));
522 return new AddINode(add1,add2);
523 }
524
525 // Disable optimization: LoadL->ConvL2I ==> LoadI.
526 // It causes problems (sizes of Load and Store nodes do not match)
527 // in objects initialization code and Escape Analysis.
528 return NULL;
529 }
530
531
532
533 //=============================================================================
534 //------------------------------Identity---------------------------------------
535 // Remove redundant roundings
536 Node* RoundFloatNode::Identity(PhaseGVN* phase) {
537 assert(Matcher::strict_fp_requires_explicit_rounding, "should only generate for Intel");
538 // Do not round constants
539 if (phase->type(in(1))->base() == Type::FloatCon) return in(1);
540 int op = in(1)->Opcode();
541 // Redundant rounding
542 if( op == Op_RoundFloat ) return in(1);
543 // Already rounded
544 if( op == Op_Parm ) return in(1);
545 if( op == Op_LoadF ) return in(1);
546 return this;
547 }
548
549 //------------------------------Value------------------------------------------
550 const Type* RoundFloatNode::Value(PhaseGVN* phase) const {
551 return phase->type( in(1) );
552 }
553
554 //=============================================================================
555 //------------------------------Identity---------------------------------------
556 // Remove redundant roundings. Incoming arguments are already rounded.
557 Node* RoundDoubleNode::Identity(PhaseGVN* phase) {
558 assert(Matcher::strict_fp_requires_explicit_rounding, "should only generate for Intel");
559 // Do not round constants
560 if (phase->type(in(1))->base() == Type::DoubleCon) return in(1);
561 int op = in(1)->Opcode();
562 // Redundant rounding
563 if( op == Op_RoundDouble ) return in(1);
564 // Already rounded
565 if( op == Op_Parm ) return in(1);
566 if( op == Op_LoadD ) return in(1);
567 if( op == Op_ConvF2D ) return in(1);
568 if( op == Op_ConvI2D ) return in(1);
569 return this;
570 }
571
572 //------------------------------Value------------------------------------------
573 const Type* RoundDoubleNode::Value(PhaseGVN* phase) const {
574 return phase->type( in(1) );
575 }
576
577 //=============================================================================
578 RoundDoubleModeNode* RoundDoubleModeNode::make(PhaseGVN& gvn, Node* arg, RoundDoubleModeNode::RoundingMode rmode) {
579 ConINode* rm = gvn.intcon(rmode);
580 return new RoundDoubleModeNode(arg, (Node *)rm);
581 }
582
583 //------------------------------Identity---------------------------------------
584 // Remove redundant roundings.
585 Node* RoundDoubleModeNode::Identity(PhaseGVN* phase) {
586 int op = in(1)->Opcode();
587 // Redundant rounding e.g. floor(ceil(n)) -> ceil(n)
588 if(op == Op_RoundDoubleMode) return in(1);
589 return this;
590 }
591 const Type* RoundDoubleModeNode::Value(PhaseGVN* phase) const {
592 return Type::DOUBLE;
593 }
594 //=============================================================================